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i-bash/subst.c
Jari Aalto bb70624e96 Imported from ../bash-2.04.tar.gz.
2009-09-12 16:46:53 +00:00

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/* subst.c -- The part of the shell that does parameter, command, and
globbing substitutions. */
/* ``Have a little faith, there's magic in the night. You ain't a
beauty, but, hey, you're alright.'' */
/* Copyright (C) 1987,1989 Free Software Foundation, Inc.
This file is part of GNU Bash, the Bourne Again SHell.
Bash is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.
Bash is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License along
with Bash; see the file COPYING. If not, write to the Free Software
Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
#include "config.h"
#include "bashtypes.h"
#include <stdio.h>
#include <pwd.h>
#include <signal.h>
#include <errno.h>
#if defined (HAVE_UNISTD_H)
# include <unistd.h>
#endif
#include "bashansi.h"
#include "posixstat.h"
#include "shell.h"
#include "flags.h"
#include "jobs.h"
#include "execute_cmd.h"
#include "filecntl.h"
#include "trap.h"
#include "pathexp.h"
#include "mailcheck.h"
#if !defined (HAVE_RESTARTABLE_SYSCALLS) /* for getc_with_restart */
#include "input.h"
#endif
#include "builtins/getopt.h"
#include "builtins/common.h"
#include <tilde/tilde.h>
#include <glob/fnmatch.h>
#if !defined (errno)
extern int errno;
#endif /* !errno */
/* The size that strings change by. */
#define DEFAULT_INITIAL_ARRAY_SIZE 112
#define DEFAULT_ARRAY_SIZE 128
/* Variable types. */
#define VT_VARIABLE 0
#define VT_POSPARMS 1
#define VT_ARRAYVAR 2
#define VT_ARRAYMEMBER 3
/* Flags for quoted_strchr */
#define ST_BACKSL 0x01
#define ST_CTLESC 0x02
/* These defs make it easier to use the editor. */
#define LBRACE '{'
#define RBRACE '}'
#define LPAREN '('
#define RPAREN ')'
/* Evaluates to 1 if this is one of the shell's special variables. */
#define SPECIAL_VAR(name, wi) \
((digit (*name) && all_digits (name)) || \
(name[1] == '\0' && member (*name, "#-?$!@*")) || \
(wi && name[2] == '\0' && member (name[1], "#?@*")))
/* Process ID of the last command executed within command substitution. */
pid_t last_command_subst_pid = NO_PID;
pid_t current_command_subst_pid = NO_PID;
/* Extern functions and variables from different files. */
extern int last_command_exit_value, interactive, interactive_shell;
extern int subshell_environment, startup_state;
extern int return_catch_flag, return_catch_value;
extern int dollar_dollar_pid;
extern int posixly_correct;
extern char *this_command_name;
extern struct fd_bitmap *current_fds_to_close;
extern int wordexp_only;
extern void getopts_reset ();
/* Non-zero means to allow unmatched globbed filenames to expand to
a null file. */
int allow_null_glob_expansion;
/* Variables to keep track of which words in an expanded word list (the
output of expand_word_list_internal) are the result of globbing
expansions. GLOB_ARGV_FLAGS is used by execute_cmd.c. */
char *glob_argv_flags;
static int glob_argv_flags_size;
static WORD_LIST expand_word_error, expand_word_fatal;
static char expand_param_error, expand_param_fatal;
static int doing_completion = 0;
static int doing_prompt_expansion = 0;
/* Used to hold a list of variable assignments preceding a command. Global
so the SIGCHLD handler in jobs.c can unwind-protect it when it runs a
SIGCHLD trap. */
WORD_LIST *subst_assign_varlist = (WORD_LIST *)NULL;
/* A WORD_LIST of words to be expanded by expand_word_list_internal,
without any leading variable assignments. */
static WORD_LIST *garglist = (WORD_LIST *)NULL;
static char *make_quoted_char ();
static void remove_quoted_nulls ();
static char *param_expand ();
static char *maybe_expand_string ();
static WORD_LIST *call_expand_word_internal ();
static WORD_LIST *expand_string_internal ();
static WORD_LIST *expand_word_internal (), *expand_word_list_internal ();
static WORD_LIST *expand_string_leave_quoted ();
static WORD_LIST *expand_string_for_rhs ();
static char *getifs ();
static WORD_LIST *word_list_split ();
static WORD_LIST *quote_list (), *dequote_list ();
static char *quote_escapes ();
static WORD_LIST *list_quote_escapes ();
static int unquoted_substring (), unquoted_member ();
static int do_assignment_internal ();
static char *string_extract_verbatim (), *string_extract ();
static char *string_extract_double_quoted (), *string_extract_single_quoted ();
static char *string_list_dollar_at (), *string_list_dollar_star ();
static inline int skip_single_quoted (), skip_double_quoted ();
static char *extract_delimited_string ();
static char *extract_dollar_brace_string ();
/* **************************************************************** */
/* */
/* Utility Functions */
/* */
/* **************************************************************** */
/* Cons a new string from STRING starting at START and ending at END,
not including END. */
char *
substring (string, start, end)
char *string;
int start, end;
{
register int len;
register char *result;
len = end - start;
result = xmalloc (len + 1);
strncpy (result, string + start, len);
result[len] = '\0';
return (result);
}
static char *
quoted_substring (string, start, end)
char *string;
int start, end;
{
register int len, l;
register char *result, *s, *r;
len = end - start;
/* Move to string[start], skipping quoted characters. */
for (s = string, l = 0; *s && l < start; )
{
if (*s == CTLESC)
{
s++;
continue;
}
l++;
if (*s == 0)
break;
}
r = result = xmalloc (2*len + 1); /* save room for quotes */
/* Copy LEN characters, including quote characters. */
s = string + l;
for (l = 0; l < len; s++)
{
if (*s == CTLESC)
*r++ = *s++;
*r++ = *s;
l++;
if (*s == 0)
break;
}
*r = '\0';
return result;
}
/* Find the first occurrence of character C in string S, obeying shell
quoting rules. If (FLAGS & ST_BACKSL) is non-zero, backslash-escaped
characters are skipped. If (FLAGS & ST_CTLESC) is non-zero, characters
escaped with CTLESC are skipped. */
static inline char *
quoted_strchr (s, c, flags)
char *s;
int c, flags;
{
register char *p;
for (p = s; *p; p++)
{
if (((flags & ST_BACKSL) && *p == '\\')
|| ((flags & ST_CTLESC) && *p == CTLESC))
{
p++;
if (*p == '\0')
return ((char *)NULL);
continue;
}
else if (*p == c)
return p;
}
return ((char *)NULL);
}
/* Return 1 if CHARACTER appears in an unquoted portion of
STRING. Return 0 otherwise. */
static int
unquoted_member (character, string)
int character;
char *string;
{
int sindex, c;
for (sindex = 0; c = string[sindex]; )
{
if (c == character)
return (1);
switch (c)
{
default:
sindex++;
break;
case '\\':
sindex++;
if (string[sindex])
sindex++;
break;
case '\'':
sindex = skip_single_quoted (string, ++sindex);
break;
case '"':
sindex = skip_double_quoted (string, ++sindex);
break;
}
}
return (0);
}
/* Return 1 if SUBSTR appears in an unquoted portion of STRING. */
static int
unquoted_substring (substr, string)
char *substr, *string;
{
int sindex, c, sublen;
if (substr == 0 || *substr == '\0')
return (0);
sublen = strlen (substr);
for (sindex = 0; c = string[sindex]; )
{
if (STREQN (string + sindex, substr, sublen))
return (1);
switch (c)
{
case '\\':
sindex++;
if (string[sindex])
sindex++;
break;
case '\'':
sindex = skip_single_quoted (string, ++sindex);
break;
case '"':
sindex = skip_double_quoted (string, ++sindex);
break;
default:
sindex++;
break;
}
}
return (0);
}
/* Most of the substitutions must be done in parallel. In order
to avoid using tons of unclear goto's, I have some functions
for manipulating malloc'ed strings. They all take INDX, a
pointer to an integer which is the offset into the string
where manipulation is taking place. They also take SIZE, a
pointer to an integer which is the current length of the
character array for this string. */
/* Append SOURCE to TARGET at INDEX. SIZE is the current amount
of space allocated to TARGET. SOURCE can be NULL, in which
case nothing happens. Gets rid of SOURCE by freeing it.
Returns TARGET in case the location has changed. */
inline char *
sub_append_string (source, target, indx, size)
char *source, *target;
int *indx, *size;
{
if (source)
{
int srclen, n;
srclen = STRLEN (source);
if (srclen >= (int)(*size - *indx))
{
n = srclen + *indx;
n = (n + DEFAULT_ARRAY_SIZE) - (n % DEFAULT_ARRAY_SIZE);
target = xrealloc (target, (*size = n));
}
FASTCOPY (source, target + *indx, srclen);
*indx += srclen;
target[*indx] = '\0';
free (source);
}
return (target);
}
#if 0
/* UNUSED */
/* Append the textual representation of NUMBER to TARGET.
INDX and SIZE are as in SUB_APPEND_STRING. */
char *
sub_append_number (number, target, indx, size)
int number, *indx, *size;
char *target;
{
char *temp;
temp = itos (number);
return (sub_append_string (temp, target, indx, size));
}
#endif
/* Extract a substring from STRING, starting at SINDEX and ending with
one of the characters in CHARLIST. Don't make the ending character
part of the string. Leave SINDEX pointing at the ending character.
Understand about backslashes in the string. If VARNAME is non-zero,
and array variables have been compiled into the shell, everything
between a `[' and a corresponding `]' is skipped over. */
static char *
string_extract (string, sindex, charlist, varname)
char *string, *charlist;
int *sindex, varname;
{
register int c, i;
char *temp;
for (i = *sindex; c = string[i]; i++)
{
if (c == '\\')
if (string[i + 1])
i++;
else
break;
#if defined (ARRAY_VARS)
else if (varname && c == '[')
{
int ni;
/* If this is an array subscript, skip over it and continue. */
ni = skipsubscript (string, i);
if (string[ni] == ']')
i = ni;
}
#endif
else if (MEMBER (c, charlist))
break;
}
temp = substring (string, *sindex, i);
*sindex = i;
return (temp);
}
/* Extract the contents of STRING as if it is enclosed in double quotes.
SINDEX, when passed in, is the offset of the character immediately
following the opening double quote; on exit, SINDEX is left pointing after
the closing double quote. If STRIPDQ is non-zero, unquoted double
quotes are stripped and the string is terminated by a null byte.
Backslashes between the embedded double quotes are processed. If STRIPDQ
is zero, an unquoted `"' terminates the string. */
static inline char *
string_extract_double_quoted (string, sindex, stripdq)
char *string;
int *sindex, stripdq;
{
int c, j, i, t;
char *temp, *ret; /* The new string we return. */
int pass_next, backquote, si; /* State variables for the machine. */
int dquote;
pass_next = backquote = dquote = 0;
temp = xmalloc (1 + strlen (string) - *sindex);
for (j = 0, i = *sindex; c = string[i]; i++)
{
/* Process a character that was quoted by a backslash. */
if (pass_next)
{
/* Posix.2 sez:
``The backslash shall retain its special meaning as an escape
character only when followed by one of the characters:
$ ` " \ <newline>''.
If STRIPDQ is zero, we handle the double quotes here and let
expand_word_internal handle the rest. If STRIPDQ is non-zero,
we have already been through one round of backslash stripping,
and want to strip these backslashes only if DQUOTE is non-zero,
indicating that we are inside an embedded double-quoted string. */
/* If we are in an embedded quoted string, then don't strip
backslashes before characters for which the backslash
retains its special meaning, but remove backslashes in
front of other characters. If we are not in an
embedded quoted string, don't strip backslashes at all.
This mess is necessary because the string was already
surrounded by double quotes (and sh has some really weird
quoting rules).
The returned string will be run through expansion as if
it were double-quoted. */
if ((stripdq == 0 && c != '"') ||
(stripdq && ((dquote && strchr (slashify_in_quotes, c)) || dquote == 0)))
temp[j++] = '\\';
temp[j++] = c;
pass_next = 0;
continue;
}
/* A backslash protects the next character. The code just above
handles preserving the backslash in front of any character but
a double quote. */
if (c == '\\')
{
pass_next++;
continue;
}
/* Inside backquotes, ``the portion of the quoted string from the
initial backquote and the characters up to the next backquote
that is not preceded by a backslash, having escape characters
removed, defines that command''. */
if (backquote)
{
if (c == '`')
backquote = 0;
temp[j++] = c;
continue;
}
if (c == '`')
{
temp[j++] = c;
backquote++;
continue;
}
/* Pass everything between `$(' and the matching `)' or a quoted
${ ... } pair through according to the Posix.2 specification. */
if (c == '$' && ((string[i + 1] == LPAREN) || (string[i + 1] == LBRACE)))
{
si = i + 2;
if (string[i + 1] == LPAREN)
ret = extract_delimited_string (string, &si, "$(", "(", ")"); /*)*/
else
ret = extract_dollar_brace_string (string, &si, 1);
temp[j++] = '$';
temp[j++] = string[i + 1];
for (t = 0; ret[t]; t++, j++)
temp[j] = ret[t];
temp[j++] = string[si];
i = si;
free (ret);
continue;
}
/* Add any character but a double quote to the quoted string we're
accumulating. */
if (c != '"')
{
temp[j++] = c;
continue;
}
/* c == '"' */
if (stripdq)
{
dquote ^= 1;
continue;
}
break;
}
temp[j] = '\0';
/* Point to after the closing quote. */
if (c)
i++;
*sindex = i;
return (temp);
}
/* This should really be another option to string_extract_double_quoted. */
static inline int
skip_double_quoted (string, sind)
char *string;
int sind;
{
int c, j, i;
char *ret;
int pass_next, backquote, si;
pass_next = backquote = 0;
for (j = 0, i = sind; c = string[i]; i++)
{
if (pass_next)
{
pass_next = 0;
continue;
}
else if (c == '\\')
{
pass_next++;
continue;
}
else if (backquote)
{
if (c == '`')
backquote = 0;
continue;
}
else if (c == '`')
{
backquote++;
continue;
}
else if (c == '$' && ((string[i + 1] == LPAREN) || (string[i + 1] == LBRACE)))
{
si = i + 2;
if (string[i + 1] == LPAREN)
ret = extract_delimited_string (string, &si, "$(", "(", ")");
else
ret = extract_dollar_brace_string (string, &si, 0);
i = si;
free (ret);
continue;
}
else if (c != '"')
continue;
else
break;
}
if (c)
i++;
return (i);
}
/* Extract the contents of STRING as if it is enclosed in single quotes.
SINDEX, when passed in, is the offset of the character immediately
following the opening single quote; on exit, SINDEX is left pointing after
the closing single quote. */
static inline char *
string_extract_single_quoted (string, sindex)
char *string;
int *sindex;
{
register int i, j;
char *t;
for (i = *sindex; string[i] && string[i] != '\''; i++)
;
t = substring (string, *sindex, i);
if (string[i])
i++;
*sindex = i;
return (t);
}
static inline int
skip_single_quoted (string, sind)
char *string;
int sind;
{
register int i;
for (i = sind; string[i] && string[i] != '\''; i++)
;
if (string[i])
i++;
return i;
}
/* Just like string_extract, but doesn't hack backslashes or any of
that other stuff. Obeys CTLESC quoting. Used to do splitting on $IFS. */
static char *
string_extract_verbatim (string, sindex, charlist)
char *string, *charlist;
int *sindex;
{
register int i = *sindex;
int c;
char *temp;
if (charlist[0] == '\'' && charlist[1] == '\0')
{
temp = string_extract_single_quoted (string, sindex);
--*sindex; /* leave *sindex at separator character */
return temp;
}
for (i = *sindex; c = string[i]; i++)
{
if (c == CTLESC)
{
i++;
continue;
}
if (MEMBER (c, charlist))
break;
}
temp = substring (string, *sindex, i);
*sindex = i;
return (temp);
}
/* Extract the $( construct in STRING, and return a new string.
Start extracting at (SINDEX) as if we had just seen "$(".
Make (SINDEX) get the position of the matching ")". */
char *
extract_command_subst (string, sindex)
char *string;
int *sindex;
{
return (extract_delimited_string (string, sindex, "$(", "(", ")"));
}
/* Extract the $[ construct in STRING, and return a new string.
Start extracting at (SINDEX) as if we had just seen "$[".
Make (SINDEX) get the position of the matching "]". */
char *
extract_arithmetic_subst (string, sindex)
char *string;
int *sindex;
{
return (extract_delimited_string (string, sindex, "$[", "[", "]"));
}
#if defined (PROCESS_SUBSTITUTION)
/* Extract the <( or >( construct in STRING, and return a new string.
Start extracting at (SINDEX) as if we had just seen "<(".
Make (SINDEX) get the position of the matching ")". */ /*))*/
char *
extract_process_subst (string, starter, sindex)
char *string;
char *starter;
int *sindex;
{
return (extract_delimited_string (string, sindex, starter, "(", ")"));
}
#endif /* PROCESS_SUBSTITUTION */
#if defined (ARRAY_VARS)
char *
extract_array_assignment_list (string, sindex)
char *string;
int *sindex;
{
return (extract_delimited_string (string, sindex, "(", (char *)NULL, ")"));
}
#endif
/* Extract and create a new string from the contents of STRING, a
character string delimited with OPENER and CLOSER. SINDEX is
the address of an int describing the current offset in STRING;
it should point to just after the first OPENER found. On exit,
SINDEX gets the position of the last character of the matching CLOSER.
If OPENER is more than a single character, ALT_OPENER, if non-null,
contains a character string that can also match CLOSER and thus
needs to be skipped. */
static char *
extract_delimited_string (string, sindex, opener, alt_opener, closer)
char *string;
int *sindex;
char *opener, *alt_opener, *closer;
{
int i, c, si;
char *t, *result;
int pass_character, nesting_level;
int len_closer, len_opener, len_alt_opener;
len_opener = STRLEN (opener);
len_alt_opener = STRLEN (alt_opener);
len_closer = STRLEN (closer);
pass_character = 0;
nesting_level = 1;
i = *sindex;
while (nesting_level)
{
c = string[i];
if (c == 0)
break;
if (pass_character) /* previous char was backslash */
{
pass_character = 0;
i++;
continue;
}
if (c == CTLESC)
{
pass_character++;
i++;
continue;
}
#if 0
if (c == '\\' && delimiter == '"' &&
(member (string[i], slashify_in_quotes)))
#else
if (c == '\\')
#endif
{
pass_character++;
i++;
continue;
}
/* Process a nested OPENER. */
if (STREQN (string + i, opener, len_opener))
{
si = i + len_opener;
t = extract_delimited_string (string, &si, opener, alt_opener, closer);
i = si + 1;
FREE (t);
continue;
}
/* Process a nested ALT_OPENER */
if (len_alt_opener && STREQN (string + i, alt_opener, len_alt_opener))
{
si = i + len_alt_opener;
t = extract_delimited_string (string, &si, alt_opener, alt_opener, closer);
i = si + 1;
FREE (t);
continue;
}
/* If the current substring terminates the delimited string, decrement
the nesting level. */
if (STREQN (string + i, closer, len_closer))
{
i += len_closer - 1; /* move to last char of the closer */
nesting_level--;
if (nesting_level == 0)
break;
}
/* Pass old-style command substitution through verbatim. */
if (c == '`')
{
si = i + 1;
t = string_extract (string, &si, "`", 0);
i = si + 1;
FREE (t);
continue;
}
/* Pass single-quoted strings through verbatim. */
if (c == '\'')
{
si = i + 1;
i = skip_single_quoted (string, si);
continue;
}
/* Pass embedded double-quoted strings through verbatim as well. */
if (c == '"')
{
si = i + 1;
i = skip_double_quoted (string, si);
continue;
}
i++; /* move past this character, which was not special. */
}
#if 0
if (c == 0 && nesting_level)
#else
if (c == 0 && nesting_level && doing_completion == 0)
#endif
{
report_error ("bad substitution: no `%s' in %s", closer, string);
jump_to_top_level (DISCARD);
}
si = i - *sindex - len_closer + 1;
result = xmalloc (1 + si);
strncpy (result, string + *sindex, si);
result[si] = '\0';
*sindex = i;
return (result);
}
/* Extract a parameter expansion expression within ${ and } from STRING.
Obey the Posix.2 rules for finding the ending `}': count braces while
skipping over enclosed quoted strings and command substitutions.
SINDEX is the address of an int describing the current offset in STRING;
it should point to just after the first `{' found. On exit, SINDEX
gets the position of the matching `}'. QUOTED is non-zero if this
occurs inside double quotes. */
/* XXX -- this is very similar to extract_delimited_string -- XXX */
static char *
extract_dollar_brace_string (string, sindex, quoted)
char *string;
int *sindex, quoted;
{
register int i, c, l;
int pass_character, nesting_level, si;
char *result, *t;
pass_character = 0;
nesting_level = 1;
for (i = *sindex; (c = string[i]); i++)
{
if (pass_character)
{
pass_character = 0;
continue;
}
/* CTLESCs and backslashes quote the next character. */
if (c == CTLESC || c == '\\')
{
pass_character++;
continue;
}
if (string[i] == '$' && string[i+1] == LBRACE)
{
nesting_level++;
i++;
continue;
}
if (c == RBRACE)
{
nesting_level--;
if (nesting_level == 0)
break;
continue;
}
/* Pass the contents of old-style command substitutions through
verbatim. */
if (c == '`')
{
si = i + 1;
t = string_extract (string, &si, "`", 0);
i = si;
free (t);
continue;
}
/* Pass the contents of new-style command substitutions and
arithmetic substitutions through verbatim. */
if (string[i] == '$' && string[i+1] == LPAREN)
{
si = i + 2;
t = extract_delimited_string (string, &si, "$(", "(", ")"); /*)*/
i = si;
free (t);
continue;
}
/* Pass the contents of single-quoted and double-quoted strings
through verbatim. */
if (c == '\'' || c == '"')
{
si = i + 1;
i = (c == '\'') ? skip_single_quoted (string, si)
: skip_double_quoted (string, si);
/* skip_XXX_quoted leaves index one past close quote */
i--;
continue;
}
}
if (c == 0 && nesting_level && doing_completion == 0)
{
report_error ("bad substitution: no ending `}' in %s", string);
jump_to_top_level (DISCARD);
}
result = substring (string, *sindex, i);
*sindex = i;
return (result);
}
/* Remove backslashes which are quoting backquotes from STRING. Modifies
STRING, and returns a pointer to it. */
char *
de_backslash (string)
char *string;
{
register int i, l;
for (i = 0, l = strlen (string); i < l; i++)
if (string[i] == '\\' && (string[i + 1] == '`' || string[i + 1] == '\\' ||
string[i + 1] == '$'))
strcpy (string + i, string + i + 1); /* XXX - should be memmove */
return (string);
}
#if 0
/*UNUSED*/
/* Replace instances of \! in a string with !. */
void
unquote_bang (string)
char *string;
{
register int i, j;
register char *temp;
temp = xmalloc (1 + strlen (string));
for (i = 0, j = 0; (temp[j] = string[i]); i++, j++)
{
if (string[i] == '\\' && string[i + 1] == '!')
{
temp[j] = '!';
i++;
}
}
strcpy (string, temp);
free (temp);
}
#endif
#if defined (READLINE)
/* Return 1 if the portion of STRING ending at EINDEX is quoted (there is
an unclosed quoted string), or if the character at EINDEX is quoted
by a backslash. DOING_COMPLETION is used to flag that the various
single and double-quoted string parsing functions should not return an
error if there are unclosed quotes or braces. */
#define CQ_RETURN(x) do { doing_completion = 0; return (x); } while (0)
int
char_is_quoted (string, eindex)
char *string;
int eindex;
{
int i, pass_next, quoted;
doing_completion = 1;
for (i = pass_next = quoted = 0; i <= eindex; i++)
{
if (pass_next)
{
pass_next = 0;
if (i >= eindex) /* XXX was if (i >= eindex - 1) */
CQ_RETURN(1);
continue;
}
else if (string[i] == '\'' || string[i] == '"')
{
i = (string[i] == '\'') ? skip_single_quoted (string, ++i)
: skip_double_quoted (string, ++i);
if (i > eindex)
CQ_RETURN(1);
i--; /* the skip functions increment past the closing quote. */
}
else if (string[i] == '\\')
{
pass_next = 1;
continue;
}
}
CQ_RETURN(0);
}
int
unclosed_pair (string, eindex, openstr)
char *string;
int eindex;
char *openstr;
{
int i, pass_next, openc, olen;
olen = strlen (openstr);
for (i = pass_next = openc = 0; i <= eindex; i++)
{
if (pass_next)
{
pass_next = 0;
if (i >= eindex) /* XXX was if (i >= eindex - 1) */
return 0;
continue;
}
else if (STREQN (string + i, openstr, olen))
{
openc = 1 - openc;
i += olen - 1;
}
else if (string[i] == '\'' || string[i] == '"')
{
i = (string[i] == '\'') ? skip_single_quoted (string, i)
: skip_double_quoted (string, i);
if (i > eindex)
return 0;
}
else if (string[i] == '\\')
{
pass_next = 1;
continue;
}
}
return (openc);
}
/* Skip characters in STRING until we find a character in DELIMS, and return
the index of that character. START is the index into string at which we
begin. This is similar in spirit to strpbrk, but it returns an index into
STRING and takes a starting index. This little piece of code knows quite
a lot of shell syntax. It's very similar to skip_double_quoted and other
functions of that ilk. */
int
skip_to_delim (string, start, delims)
char *string;
int start;
char *delims;
{
int i, pass_next, backq, si;
char *temp;
doing_completion = 1;
for (i = start, pass_next = backq = 0; string[i]; i++)
{
if (pass_next)
{
pass_next = 0;
if (string[i] == 0)
CQ_RETURN(i);
continue;
}
else if (string[i] == '\\')
{
pass_next = 1;
continue;
}
else if (backq)
{
if (string[i] == '`')
backq = 0;
continue;
}
else if (string[i] == '`')
{
backq = 1;
continue;
}
else if (string[i] == '\'' || string[i] == '"')
{
i = (string[i] == '\'') ? skip_single_quoted (string, ++i)
: skip_double_quoted (string, ++i);
i--; /* the skip functions increment past the closing quote. */
}
else if (string[i] == '$' && (string[i+1] == LPAREN || string[i+1] == LBRACE))
{
si = i + 2;
if (string[si] == '\0')
break;
if (string[i+1] == LPAREN)
temp = extract_delimited_string (string, &si, "$(", "(", ")"); /* ) */
else
temp = extract_dollar_brace_string (string, &si, 0);
i = si;
free (temp);
continue;
}
else if (member (string[i], delims))
break;
}
CQ_RETURN(i);
}
/* Split STRING (length SLEN) at DELIMS, and return a WORD_LIST with the
individual words. If DELIMS is NULL, the current value of $IFS is used
to split the string. SENTINEL is an index to look for. NWP, if non-NULL
gets the number of words in the returned list. CWP, if non-NULL, gets
the index of the word containing SENTINEL. Non-whitespace chars in
DELIMS delimit separate fields. */
WORD_LIST *
split_at_delims (string, slen, delims, sentinel, nwp, cwp)
char *string;
int slen;
char *delims;
int sentinel;
int *nwp, *cwp;
{
int ts, te, i, nw, cw, peekc;
char *token, *s, *d, *d2;
WORD_LIST *ret, *tl;
if (string == 0 || *string == '\0')
{
if (nwp)
*nwp = 0;
if (cwp)
*cwp = 0;
return ((WORD_LIST *)NULL);
}
d = (delims == 0) ? getifs () : delims;
/* Make d2 the non-whitespace characters in delims */
d2 = 0;
if (delims)
{
d2 = xmalloc (strlen (delims) + 1);
for (i = ts = 0; delims[i]; i++)
{
if (whitespace(delims[i]) == 0)
d2[ts++] = delims[i];
}
d2[ts] = '\0';
}
ret = (WORD_LIST *)NULL;
for (i = 0; member (string[i], d) && whitespace(string[i]); i++)
;
if (string[i] == '\0')
return (ret);
ts = i;
nw = 0;
cw = -1;
while (1)
{
te = skip_to_delim (string, ts, d);
/* If we have a non-whitespace delimiter character, use it to make a
separate field. This is just about what $IFS splitting does and
is closer to the behavior of the shell parser. */
if (ts == te && member(string[ts], d2))
{
te = ts + 1;
while (member(string[te], d2))
te++;
}
token = substring (string, ts, te);
ret = add_string_to_list (token, ret);
free (token);
nw++;
if (sentinel >= ts && sentinel <= te)
cw = nw;
/* If the cursor is at whitespace just before word start, set the
sentinel word to the current word. */
if (cwp && cw == -1 && sentinel == ts-1)
cw = nw;
/* If the cursor is at whitespace between two words, make a new, empty
word, add it before (well, after, since the list is in reverse order)
the word we just added, and set the current word to that one. */
if (cwp && cw == -1 && sentinel < ts)
{
tl = (WORD_LIST *)xmalloc (sizeof (WORD_LIST));
tl->word = make_word ("");
tl->next = ret->next;
ret->next = tl;
cw = nw;
nw++;
}
if (string[te] == 0)
break;
i = te + member(string[te], d);
while (member (string[i], d) && whitespace(string[i]))
i++;
if (string[i])
ts = i;
else
break;
}
/* Special case for SENTINEL at the end of STRING. If we haven't found
the word containing SENTINEL yet, and the index we're looking for is at
the end of STRING, add an additional null argument and set the current
word pointer to that. */
if (cwp && cw == -1 && sentinel >= slen)
{
if (whitespace (string[sentinel - 1]))
{
token = "";
ret = add_string_to_list (token, ret);
nw++;
}
cw = nw;
}
if (nwp)
*nwp = nw;
if (cwp)
*cwp = cw;
return (REVERSE_LIST (ret, WORD_LIST *));
}
#endif /* READLINE */
#if 0
/* UNUSED */
/* Extract the name of the variable to bind to from the assignment string. */
char *
assignment_name (string)
char *string;
{
int offset;
char *temp;
offset = assignment (string);
if (offset == 0)
return (char *)NULL;
temp = substring (string, 0, offset);
return (temp);
}
#endif
/* **************************************************************** */
/* */
/* Functions to convert strings to WORD_LISTs and vice versa */
/* */
/* **************************************************************** */
/* Return a single string of all the words in LIST. SEP is the separator
to put between individual elements of LIST in the output string. */
static char *
string_list_internal (list, sep)
WORD_LIST *list;
char *sep;
{
register WORD_LIST *t;
char *result, *r;
int word_len, sep_len, result_size;
if (list == 0)
return ((char *)NULL);
/* This is nearly always called with either sep[0] == 0 or sep[1] == 0. */
sep_len = STRLEN (sep);
result_size = 0;
for (t = list; t; t = t->next)
{
if (t != list)
result_size += sep_len;
result_size += strlen (t->word->word);
}
r = result = xmalloc (result_size + 1);
for (t = list; t; t = t->next)
{
if (t != list && sep_len)
{
if (sep_len > 1)
{
FASTCOPY (sep, r, sep_len);
r += sep_len;
}
else
*r++ = sep[0];
}
word_len = strlen (t->word->word);
FASTCOPY (t->word->word, r, word_len);
r += word_len;
}
*r = '\0';
return (result);
}
/* Return a single string of all the words present in LIST, separating
each word with a space. */
char *
string_list (list)
WORD_LIST *list;
{
return (string_list_internal (list, " "));
}
/* Return a single string of all the words present in LIST, obeying the
quoting rules for "$*", to wit: (P1003.2, draft 11, 3.5.2) "If the
expansion [of $*] appears within a double quoted string, it expands
to a single field with the value of each parameter separated by the
first character of the IFS variable, or by a <space> if IFS is unset." */
static char *
string_list_dollar_star (list)
WORD_LIST *list;
{
char *ifs, sep[2];
ifs = get_string_value ("IFS");
sep[0] = (ifs == 0) ? ' ' : *ifs;
sep[1] = '\0';
return (string_list_internal (list, sep));
}
/* Turn $@ into a string. If (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES))
is non-zero, the $@ appears within double quotes, and we should quote
the list before converting it into a string. If IFS is unset, and the
word is not quoted, we just need to quote CTLESC and CTLNUL characters
in the words in the list, because the default value of $IFS is
<space><tab><newline>, IFS characters in the words in the list should
also be split. If IFS is null, and the word is not quoted, we need
to quote the words in the list to preserve the positional parameters
exactly. */
static char *
string_list_dollar_at (list, quoted)
WORD_LIST *list;
int quoted;
{
char *ifs, sep[2];
WORD_LIST *tlist;
ifs = get_string_value ("IFS");
sep[0] = (ifs == 0 || *ifs == 0) ? ' ' : *ifs;
sep[1] = '\0';
tlist = ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) || (ifs && *ifs == 0))
? quote_list (list)
: list_quote_escapes (list);
return (string_list_internal (tlist, sep));
}
/* Return the list of words present in STRING. Separate the string into
words at any of the characters found in SEPARATORS. If QUOTED is
non-zero then word in the list will have its quoted flag set, otherwise
the quoted flag is left as make_word () deemed fit.
This obeys the P1003.2 word splitting semantics. If `separators' is
exactly <space><tab><newline>, then the splitting algorithm is that of
the Bourne shell, which treats any sequence of characters from `separators'
as a delimiter. If IFS is unset, which results in `separators' being set
to "", no splitting occurs. If separators has some other value, the
following rules are applied (`IFS white space' means zero or more
occurrences of <space>, <tab>, or <newline>, as long as those characters
are in `separators'):
1) IFS white space is ignored at the start and the end of the
string.
2) Each occurrence of a character in `separators' that is not
IFS white space, along with any adjacent occurrences of
IFS white space delimits a field.
3) Any nonzero-length sequence of IFS white space delimits a field.
*/
/* BEWARE! list_string strips null arguments. Don't call it twice and
expect to have "" preserved! */
/* This performs word splitting and quoted null character removal on
STRING. */
#define issep(c) (member ((c), separators))
WORD_LIST *
list_string (string, separators, quoted)
register char *string, *separators;
int quoted;
{
WORD_LIST *result;
WORD_DESC *t;
char *current_word, *s;
int sindex, sh_style_split;
if (!string || !*string)
return ((WORD_LIST *)NULL);
sh_style_split =
separators && *separators && (STREQ (separators, " \t\n"));
/* Remove sequences of whitespace at the beginning of STRING, as
long as those characters appear in IFS. Do not do this if
STRING is quoted or if there are no separator characters. */
if (!quoted || !separators || !*separators)
{
for (s = string; *s && spctabnl (*s) && issep (*s); s++);
if (!*s)
return ((WORD_LIST *)NULL);
string = s;
}
/* OK, now STRING points to a word that does not begin with white space.
The splitting algorithm is:
extract a word, stopping at a separator
skip sequences of spc, tab, or nl as long as they are separators
This obeys the field splitting rules in Posix.2. */
for (result = (WORD_LIST *)NULL, sindex = 0; string[sindex]; )
{
current_word = string_extract_verbatim (string, &sindex, separators);
if (current_word == 0)
break;
/* If we have a quoted empty string, add a quoted null argument. We
want to preserve the quoted null character iff this is a quoted
empty string; otherwise the quoted null characters are removed
below. */
if (QUOTED_NULL (current_word))
{
t = make_bare_word ("");
t->flags |= W_QUOTED;
free (t->word);
t->word = make_quoted_char ('\0');
result = make_word_list (t, result);
}
else if (current_word[0] != '\0')
{
/* If we have something, then add it regardless. However,
perform quoted null character removal on the current word. */
remove_quoted_nulls (current_word);
result = add_string_to_list (current_word, result);
if (quoted & (Q_DOUBLE_QUOTES|Q_HERE_DOCUMENT))
result->word->flags |= W_QUOTED;
}
/* If we're not doing sequences of separators in the traditional
Bourne shell style, then add a quoted null argument. */
else if (!sh_style_split && !spctabnl (string[sindex]))
{
t = make_bare_word ("");
t->flags |= W_QUOTED;
free (t->word);
t->word = make_quoted_char ('\0');
result = make_word_list (t, result);
}
free (current_word);
/* Move past the current separator character. */
if (string[sindex])
sindex++;
/* Now skip sequences of space, tab, or newline characters if they are
in the list of separators. */
while (string[sindex] && spctabnl (string[sindex]) && issep (string[sindex]))
sindex++;
}
return (REVERSE_LIST (result, WORD_LIST *));
}
/* Parse a single word from STRING, using SEPARATORS to separate fields.
ENDPTR is set to the first character after the word. This is used by
the `read' builtin.
XXX - this function is very similar to list_string; they should be
combined - XXX */
char *
get_word_from_string (stringp, separators, endptr)
char **stringp, *separators, **endptr;
{
register char *s;
char *current_word;
int sindex, sh_style_split;
if (!stringp || !*stringp || !**stringp)
return ((char *)NULL);
s = *stringp;
sh_style_split =
separators && *separators && (STREQ (separators, " \t\n"));
/* Remove sequences of whitespace at the beginning of STRING, as
long as those characters appear in IFS. */
if (sh_style_split || !separators || !*separators)
{
for (; *s && spctabnl (*s) && issep (*s); s++);
/* If the string is nothing but whitespace, update it and return. */
if (!*s)
{
*stringp = s;
if (endptr)
*endptr = s;
return ((char *)NULL);
}
}
/* OK, S points to a word that does not begin with white space.
Now extract a word, stopping at a separator, save a pointer to
the first character after the word, then skip sequences of spc,
tab, or nl as long as they are separators.
This obeys the field splitting rules in Posix.2. */
sindex = 0;
current_word = string_extract_verbatim (s, &sindex, separators);
/* Set ENDPTR to the first character after the end of the word. */
if (endptr)
*endptr = s + sindex;
/* Move past the current separator character. */
if (s[sindex])
sindex++;
/* Now skip sequences of space, tab, or newline characters if they are
in the list of separators. */
while (s[sindex] && spctabnl (s[sindex]) && issep (s[sindex]))
sindex++;
/* Update STRING to point to the next field. */
*stringp = s + sindex;
return (current_word);
}
/* Remove IFS white space at the end of STRING. Start at the end
of the string and walk backwards until the beginning of the string
or we find a character that's not IFS white space and not CTLESC.
Only let CTLESC escape a white space character if SAW_ESCAPE is
non-zero. */
char *
strip_trailing_ifs_whitespace (string, separators, saw_escape)
char *string, *separators;
int saw_escape;
{
char *s;
s = string + STRLEN (string) - 1;
while (s > string && ((spctabnl (*s) && issep (*s)) ||
(saw_escape && *s == CTLESC && spctabnl (s[1]))))
s--;
*++s = '\0';
return string;
}
#if 0
/* UNUSED */
/* Split STRING into words at whitespace. Obeys shell-style quoting with
backslashes, single and double quotes. */
WORD_LIST *
list_string_with_quotes (string)
char *string;
{
WORD_LIST *list;
char *token, *s;
int c, i, tokstart, len;
for (s = string; s && *s && spctabnl (*s); s++)
;
if (s == 0 || *s == 0)
return ((WORD_LIST *)NULL);
tokstart = i = 0;
list = (WORD_LIST *)NULL;
while (1)
{
c = s[i];
if (c == '\\')
{
i++;
if (s[i])
i++;
}
else if (c == '\'')
i = skip_single_quoted (s, ++i);
else if (c == '"')
i = skip_double_quoted (s, ++i);
else if (c == 0 || spctabnl (c))
{
/* We have found the end of a token. Make a word out of it and
add it to the word list. */
token = substring (s, tokstart, i);
list = add_string_to_list (token, list);
free (token);
while (spctabnl (s[i]))
i++;
if (s[i])
tokstart = i;
else
break;
}
else
i++; /* normal character */
}
return (REVERSE_LIST (list, WORD_LIST *));
}
#endif
/********************************************************/
/* */
/* Functions to perform assignment statements */
/* */
/********************************************************/
#if defined (ARRAY_VARS)
SHELL_VAR *
do_array_element_assignment (name, value)
char *name, *value;
{
char *t;
int ind, ni;
SHELL_VAR *entry;
t = strchr (name, '[');
if (t == 0)
return ((SHELL_VAR *)NULL);
ind = t - name;
ni = skipsubscript (name, ind);
if ((ALL_ELEMENT_SUB (t[1]) && t[2] == ']') || (ni <= ind + 1))
{
report_error ("%s: bad array subscript", name);
return ((SHELL_VAR *)NULL);
}
*t++ = '\0';
ind = array_expand_index (t, ni - ind);
if (ind < 0)
{
t[-1] = '['; /* restore original name */
report_error ("%s: bad array subscript", name);
return ((SHELL_VAR *)NULL);
}
entry = bind_array_variable (name, ind, value);
t[-1] = '['; /* restore original name */
return (entry);
}
#endif /* ARRAY_VARS */
/* Given STRING, an assignment string, get the value of the right side
of the `=', and bind it to the left side. If EXPAND is true, then
perform parameter expansion, command substitution, and arithmetic
expansion on the right-hand side. Perform tilde expansion in any
case. Do not perform word splitting on the result of expansion. */
static int
do_assignment_internal (string, expand)
char *string;
int expand;
{
int offset;
char *name, *value;
SHELL_VAR *entry;
#if defined (ARRAY_VARS)
char *t;
int ni, assign_list = 0;
#endif
offset = assignment (string);
name = savestring (string);
value = (char *)NULL;
if (name[offset] == '=')
{
char *temp;
name[offset] = 0;
temp = name + offset + 1;
#if defined (ARRAY_VARS)
if (expand && temp[0] == LPAREN && strchr (temp, RPAREN))
{
assign_list = ni = 1;
value = extract_delimited_string (temp, &ni, "(", (char *)NULL, ")");
}
else
#endif
/* Perform tilde expansion. */
if (expand && temp[0])
{
temp = (strchr (temp, '~') && unquoted_member ('~', temp))
? bash_tilde_expand (temp)
: savestring (temp);
value = maybe_expand_string (temp, 0, expand_string_unsplit);
free (temp);
}
else
value = savestring (temp);
}
if (value == 0)
{
value = xmalloc (1);
value[0] = '\0';
}
if (echo_command_at_execute)
#if defined (ARRAY_VARS)
if (assign_list)
fprintf (stderr, "%s%s=(%s)\n", indirection_level_string (), name, value);
else
#endif
fprintf (stderr, "%s%s=%s\n", indirection_level_string (), name, value);
#define ASSIGN_RETURN(r) do { FREE (value); free (name); return (r); } while (0)
#if defined (ARRAY_VARS)
if (t = strchr (name, '['))
{
if (assign_list)
{
report_error ("%s: cannot assign list to array member", name);
ASSIGN_RETURN (0);
}
entry = do_array_element_assignment (name, value);
if (entry == 0)
ASSIGN_RETURN (0);
}
else if (assign_list)
entry = assign_array_from_string (name, value);
else
#endif /* ARRAY_VARS */
entry = bind_variable (name, value);
stupidly_hack_special_variables (name);
if (entry)
VUNSETATTR (entry, att_invisible);
/* Return 1 if the assignment seems to have been performed correctly. */
ASSIGN_RETURN (entry ? (readonly_p (entry) == 0) : 0);
}
/* Perform the assignment statement in STRING, and expand the
right side by doing command and parameter expansion. */
int
do_assignment (string)
char *string;
{
return do_assignment_internal (string, 1);
}
/* Given STRING, an assignment string, get the value of the right side
of the `=', and bind it to the left side. Do not do command and
parameter substitution on the right hand side. */
int
do_assignment_no_expand (string)
char *string;
{
return do_assignment_internal (string, 0);
}
/***************************************************
* *
* Functions to manage the positional parameters *
* *
***************************************************/
/* Return the word list that corresponds to `$*'. */
WORD_LIST *
list_rest_of_args ()
{
register WORD_LIST *list, *args;
int i;
/* Break out of the loop as soon as one of the dollar variables is null. */
for (i = 1, list = (WORD_LIST *)NULL; i < 10 && dollar_vars[i]; i++)
list = make_word_list (make_bare_word (dollar_vars[i]), list);
for (args = rest_of_args; args; args = args->next)
list = make_word_list (make_bare_word (args->word->word), list);
return (REVERSE_LIST (list, WORD_LIST *));
}
int
number_of_args ()
{
register WORD_LIST *list;
int n;
for (n = 0; n < 9 && dollar_vars[n+1]; n++)
;
for (list = rest_of_args; list; list = list->next)
n++;
return n;
}
/* Return the value of a positional parameter. This handles values > 10. */
char *
get_dollar_var_value (ind)
int ind;
{
char *temp;
WORD_LIST *p;
if (ind < 10)
temp = dollar_vars[ind] ? savestring (dollar_vars[ind]) : (char *)NULL;
else /* We want something like ${11} */
{
ind -= 10;
for (p = rest_of_args; p && ind--; p = p->next)
;
temp = p ? savestring (p->word->word) : (char *)NULL;
}
return (temp);
}
/* Make a single large string out of the dollar digit variables,
and the rest_of_args. If DOLLAR_STAR is 1, then obey the special
case of "$*" with respect to IFS. */
char *
string_rest_of_args (dollar_star)
int dollar_star;
{
register WORD_LIST *list;
char *string;
list = list_rest_of_args ();
string = dollar_star ? string_list_dollar_star (list) : string_list (list);
dispose_words (list);
return (string);
}
/* Return a string containing the positional parameters from START to
END, inclusive. If STRING[0] == '*', we obey the rules for $*,
which only makes a difference if QUOTED is non-zero. */
static char *
pos_params (string, start, end, quoted)
char *string;
int start, end, quoted;
{
WORD_LIST *save, *params, *h, *t;
char *ret;
int i;
/* see if we can short-circuit. if start == end, we want 0 parameters. */
if (start == end)
return ((char *)NULL);
save = params = list_rest_of_args ();
if (save == 0)
return ((char *)NULL);
for (i = 1; params && i < start; i++)
params = params->next;
if (params == 0)
return ((char *)NULL);
for (h = t = params; params && i < end; i++)
{
t = params;
params = params->next;
}
t->next = (WORD_LIST *)NULL;
if (string[0] == '*')
ret = (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) ? string_list_dollar_star (h) : string_list (h);
else
ret = string_list ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) ? quote_list (h) : h);
if (t != params)
t->next = params;
dispose_words (save);
return (ret);
}
/******************************************************************/
/* */
/* Functions to expand strings to strings or WORD_LISTs */
/* */
/******************************************************************/
#if defined (PROCESS_SUBSTITUTION)
#define EXP_CHAR(s) (s == '$' || s == '`' || s == '<' || s == '>' || s == CTLESC)
#else
#define EXP_CHAR(s) (s == '$' || s == '`' || s == CTLESC)
#endif
/* If there are any characters in STRING that require full expansion,
then call FUNC to expand STRING; otherwise just perform quote
removal if necessary. This returns a new string. */
static char *
maybe_expand_string (string, quoted, func)
char *string;
int quoted;
WORD_LIST *(*func)();
{
WORD_LIST *list;
int i, saw_quote;
char *ret;
for (i = saw_quote = 0; string[i]; i++)
{
if (EXP_CHAR (string[i]))
break;
else if (string[i] == '\'' || string[i] == '\\' || string[i] == '"')
saw_quote = 1;
}
if (string[i])
{
list = (*func) (string, quoted);
if (list)
{
ret = string_list (list);
dispose_words (list);
}
else
ret = (char *)NULL;
}
else if (saw_quote && ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) == 0))
ret = string_quote_removal (string, quoted);
else
ret = savestring (string);
return ret;
}
static inline char *
expand_string_to_string (string, quoted, func)
char *string;
int quoted;
WORD_LIST *(*func)();
{
WORD_LIST *list;
char *ret;
if (string == 0 || *string == '\0')
return ((char *)NULL);
list = (*func) (string, quoted);
if (list)
{
ret = string_list (list);
dispose_words (list);
}
else
ret = (char *)NULL;
return (ret);
}
#if defined (COND_COMMAND)
/* Just remove backslashes in STRING. Returns a new string. */
char *
remove_backslashes (string)
char *string;
{
char *r, *ret, *s;
r = ret = xmalloc (strlen (string) + 1);
for (s = string; s && *s; )
{
if (*s == '\\')
s++;
if (*s == 0)
break;
*r++ = *s++;
}
*r = '\0';
return ret;
}
/* This needs better error handling. */
/* Expand W for use as an argument to a unary or binary operator in a
[[...]] expression. If SPECIAL is nonzero, this is the rhs argument
to the != or == operator, and should be treated as a pattern. In
this case, we quote the string specially for the globbing code. The
caller is responsible for removing the backslashes if the unquoted
words is needed later. */
char *
cond_expand_word (w, special)
WORD_DESC *w;
int special;
{
char *r, *p;
WORD_LIST *l;
if (w->word == 0 || w->word[0] == '\0')
return ((char *)NULL);
l = call_expand_word_internal (w, 0, 0, (int *)0, (int *)0);
if (l)
{
if (special == 0)
{
dequote_list (l);
r = string_list (l);
}
else
{
p = string_list (l);
r = quote_string_for_globbing (p, QGLOB_CVTNULL);
free (p);
}
dispose_words (l);
}
else
r = (char *)NULL;
return r;
}
#endif
/* Call expand_word_internal to expand W and handle error returns.
A convenience function for functions that don't want to handle
any errors or free any memory before aborting. */
static WORD_LIST *
call_expand_word_internal (w, q, i, c, e)
WORD_DESC *w;
int q, i, *c, *e;
{
WORD_LIST *result;
result = expand_word_internal (w, q, i, c, e);
if (result == &expand_word_error || result == &expand_word_fatal)
{
/* By convention, each time this error is returned, w->word has
already been freed (it sometimes may not be in the fatal case,
but that doesn't result in a memory leak because we're going
to exit in most cases). */
w->word = (char *)NULL;
jump_to_top_level ((result == &expand_word_error) ? DISCARD : FORCE_EOF);
/* NOTREACHED */
}
else
return (result);
}
/* Perform parameter expansion, command substitution, and arithmetic
expansion on STRING, as if it were a word. Leave the result quoted. */
static WORD_LIST *
expand_string_internal (string, quoted)
char *string;
int quoted;
{
WORD_DESC td;
WORD_LIST *tresult;
if (string == 0 || *string == 0)
return ((WORD_LIST *)NULL);
bzero ((char *)&td, sizeof (td));
td.word = string;
tresult = call_expand_word_internal (&td, quoted, 0, (int *)NULL, (int *)NULL);
return (tresult);
}
/* Expand STRING by performing parameter expansion, command substitution,
and arithmetic expansion. Dequote the resulting WORD_LIST before
returning it, but do not perform word splitting. The call to
remove_quoted_nulls () is in here because word splitting normally
takes care of quote removal. */
WORD_LIST *
expand_string_unsplit (string, quoted)
char *string;
int quoted;
{
WORD_LIST *value;
if (!string || !*string)
return ((WORD_LIST *)NULL);
value = expand_string_internal (string, quoted);
if (value)
{
if (value->word)
remove_quoted_nulls (value->word->word);
dequote_list (value);
}
return (value);
}
/* Expand one of the PS? prompt strings. This is a sort of combination of
expand_string_unsplit and expand_string_internal, but returns the
passed string when an error occurs. Might want to trap other calls
to jump_to_top_level here so we don't endlessly loop. */
WORD_LIST *
expand_prompt_string (string, quoted)
char *string;
int quoted;
{
WORD_LIST *value;
WORD_DESC td;
if (string == 0 || *string == 0)
return ((WORD_LIST *)NULL);
bzero ((char *)&td, sizeof (td));
td.word = savestring (string);
doing_prompt_expansion = 1;
value = expand_word_internal (&td, quoted, 0, (int *)NULL, (int *)NULL);
doing_prompt_expansion = 0;
if (value == &expand_word_error || value == &expand_word_fatal)
{
value = make_word_list (make_bare_word (string), (WORD_LIST *)NULL);
return value;
}
FREE (td.word);
if (value)
{
if (value->word)
remove_quoted_nulls (value->word->word);
dequote_list (value);
}
return (value);
}
/* Expand STRING just as if you were expanding a word, but do not dequote
the resultant WORD_LIST. This is called only from within this file,
and is used to correctly preserve quoted characters when expanding
things like ${1+"$@"}. This does parameter expansion, command
substitution, arithmetic expansion, and word splitting. */
static WORD_LIST *
expand_string_leave_quoted (string, quoted)
char *string;
int quoted;
{
WORD_LIST *tlist;
WORD_LIST *tresult;
if (string == 0 || *string == '\0')
return ((WORD_LIST *)NULL);
tlist = expand_string_internal (string, quoted);
if (tlist)
{
tresult = word_list_split (tlist);
dispose_words (tlist);
return (tresult);
}
return ((WORD_LIST *)NULL);
}
/* This does not perform word splitting or dequote the WORD_LIST
it returns. */
static WORD_LIST *
expand_string_for_rhs (string, quoted, dollar_at_p, has_dollar_at)
char *string;
int quoted, *dollar_at_p, *has_dollar_at;
{
WORD_DESC td;
WORD_LIST *tresult;
if (string == 0 || *string == '\0')
return (WORD_LIST *)NULL;
bzero ((char *)&td, sizeof (td));
td.word = string;
tresult = call_expand_word_internal (&td, quoted, 1, dollar_at_p, has_dollar_at);
return (tresult);
}
/* Expand STRING just as if you were expanding a word. This also returns
a list of words. Note that filename globbing is *NOT* done for word
or string expansion, just when the shell is expanding a command. This
does parameter expansion, command substitution, arithmetic expansion,
and word splitting. Dequote the resultant WORD_LIST before returning. */
WORD_LIST *
expand_string (string, quoted)
char *string;
int quoted;
{
WORD_LIST *result;
if (!string || !*string)
return ((WORD_LIST *)NULL);
result = expand_string_leave_quoted (string, quoted);
return (result ? dequote_list (result) : result);
}
/***************************************************
* *
* Functions to handle quoting chars *
* *
***************************************************/
/* Conventions:
A string with s[0] == CTLNUL && s[1] == 0 is a quoted null string.
The parser passes CTLNUL as CTLESC CTLNUL. */
/* The parser passes us CTLESC as CTLESC CTLESC and CTLNUL as CTLESC CTLNUL.
This is necessary to make unquoted CTLESC and CTLNUL characters in the
data stream pass through properly.
Here we remove doubled CTLESC characters inside quoted strings before
quoting the entire string, so we do not double the number of CTLESC
characters. */
static char *
remove_quoted_escapes (string)
char *string;
{
register char *s;
int docopy;
char *t, *t1;
if (string == NULL)
return (string);
t1 = t = xmalloc (strlen (string) + 1);
for (docopy = 0, s = string; *s; s++, t1++)
{
if (*s == CTLESC && (s[1] == CTLESC || s[1] == CTLNUL))
{
s++;
docopy = 1;
}
*t1 = *s;
}
*t1 = '\0';
if (docopy)
strcpy (string, t);
free (t);
return (string);
}
/* Quote escape characters in string s, but no other characters. This is
used to protect CTLESC and CTLNUL in variable values from the rest of
the word expansion process after the variable is expanded. */
static char *
quote_escapes (string)
char *string;
{
register char *s, *t;
char *result;
result = xmalloc ((strlen (string) * 2) + 1);
for (s = string, t = result; *s; )
{
if (*s == CTLESC || *s == CTLNUL)
*t++ = CTLESC;
*t++ = *s++;
}
*t = '\0';
return (result);
}
static WORD_LIST *
list_quote_escapes (list)
WORD_LIST *list;
{
register WORD_LIST *w;
char *t;
for (w = list; w; w = w->next)
{
t = w->word->word;
w->word->word = quote_escapes (t);
free (t);
}
return list;
}
#if 0
/* UNUSED */
static char *
dequote_escapes (string)
char *string;
{
register char *s, *t;
char *result;
result = xmalloc (strlen (string) + 1);
for (s = string, t = result; *s; )
{
if (*s == CTLESC && (s[1] == CTLESC || s[1] == CTLNUL))
{
s++;
if (*s == '\0')
break;
}
*t++ = *s++;
}
*t = '\0';
return result;
}
#endif
static WORD_LIST *
dequote_list (list)
WORD_LIST *list;
{
register char *s;
register WORD_LIST *tlist;
for (tlist = list; tlist; tlist = tlist->next)
{
s = dequote_string (tlist->word->word);
free (tlist->word->word);
tlist->word->word = s;
}
return list;
}
/* Return a new string with the quoted representation of character C. */
static char *
make_quoted_char (c)
int c;
{
char *temp;
temp = xmalloc (3);
if (c == 0)
{
temp[0] = CTLNUL;
temp[1] = '\0';
}
else
{
temp[0] = CTLESC;
temp[1] = c;
temp[2] = '\0';
}
return (temp);
}
/* Quote STRING. Return a new string. */
char *
quote_string (string)
char *string;
{
register char *t;
char *result;
if (*string == 0)
{
result = xmalloc (2);
result[0] = CTLNUL;
result[1] = '\0';
}
else
{
result = xmalloc ((strlen (string) * 2) + 1);
for (t = result; *string; )
{
*t++ = CTLESC;
*t++ = *string++;
}
*t = '\0';
}
return (result);
}
/* De-quoted quoted characters in STRING. */
char *
dequote_string (string)
char *string;
{
register char *t;
char *result;
result = xmalloc (strlen (string) + 1);
if (QUOTED_NULL (string))
{
result[0] = '\0';
return (result);
}
/* If no character in the string can be quoted, don't bother examining
each character. Just return a copy of the string passed to us. */
if (strchr (string, CTLESC) == NULL) /* XXX */
{ /* XXX */
strcpy (result, string); /* XXX */
return (result); /* XXX */
}
for (t = result; *string; string++, t++)
{
if (*string == CTLESC)
{
string++;
if (!*string)
break;
}
*t = *string;
}
*t = '\0';
return (result);
}
/* Quote the entire WORD_LIST list. */
static WORD_LIST *
quote_list (list)
WORD_LIST *list;
{
register WORD_LIST *w;
char *t;
for (w = list; w; w = w->next)
{
t = w->word->word;
w->word->word = quote_string (t);
free (t);
w->word->flags |= W_QUOTED;
}
return list;
}
/* Perform quoted null character removal on STRING. We don't allow any
quoted null characters in the middle or at the ends of strings because
of how expand_word_internal works. remove_quoted_nulls () turns
STRING into an empty string iff it only consists of a quoted null,
and removes all unquoted CTLNUL characters. */
/*
#define remove_quoted_nulls(string) \
do { if (QUOTED_NULL (string)) string[0] ='\0'; } while (0)
*/
static void
remove_quoted_nulls (string)
char *string;
{
char *nstr, *s, *p;
nstr = savestring (string);
nstr[0] = '\0';
for (p = nstr, s = string; *s; s++)
{
if (*s == CTLESC)
{
*p++ = *s++; /* CTLESC */
if (*s == 0)
break;
*p++ = *s; /* quoted char */
continue;
}
if (*s == CTLNUL)
continue;
*p++ = *s;
}
*p = '\0';
strcpy (string, nstr);
free (nstr);
}
/* Perform quoted null character removal on each element of LIST.
This modifies LIST. */
void
word_list_remove_quoted_nulls (list)
WORD_LIST *list;
{
register WORD_LIST *t;
for (t = list; t; t = t->next)
remove_quoted_nulls (t->word->word);
}
/* **************************************************************** */
/* */
/* Functions for Matching and Removing Patterns */
/* */
/* **************************************************************** */
/* Remove the portion of PARAM matched by PATTERN according to OP, where OP
can have one of 4 values:
RP_LONG_LEFT remove longest matching portion at start of PARAM
RP_SHORT_LEFT remove shortest matching portion at start of PARAM
RP_LONG_RIGHT remove longest matching portion at end of PARAM
RP_SHORT_RIGHT remove shortest matching portion at end of PARAM
*/
#define RP_LONG_LEFT 1
#define RP_SHORT_LEFT 2
#define RP_LONG_RIGHT 3
#define RP_SHORT_RIGHT 4
static char *
remove_pattern (param, pattern, op)
char *param, *pattern;
int op;
{
register int len;
register char *end;
register char *p, *ret, c;
if (param == NULL || *param == '\0')
return (param);
if (pattern == NULL || *pattern == '\0') /* minor optimization */
return (savestring (param));
len = STRLEN (param);
end = param + len;
switch (op)
{
case RP_LONG_LEFT: /* remove longest match at start */
for (p = end; p >= param; p--)
{
c = *p; *p = '\0';
if (fnmatch (pattern, param, FNMATCH_EXTFLAG) != FNM_NOMATCH)
{
*p = c;
return (savestring (p));
}
*p = c;
}
break;
case RP_SHORT_LEFT: /* remove shortest match at start */
for (p = param; p <= end; p++)
{
c = *p; *p = '\0';
if (fnmatch (pattern, param, FNMATCH_EXTFLAG) != FNM_NOMATCH)
{
*p = c;
return (savestring (p));
}
*p = c;
}
break;
case RP_LONG_RIGHT: /* remove longest match at end */
for (p = param; p <= end; p++)
{
if (fnmatch (pattern, p, FNMATCH_EXTFLAG) != FNM_NOMATCH)
{
c = *p; *p = '\0';
ret = savestring (param);
*p = c;
return (ret);
}
}
break;
case RP_SHORT_RIGHT: /* remove shortest match at end */
for (p = end; p >= param; p--)
{
if (fnmatch (pattern, p, FNMATCH_EXTFLAG) != FNM_NOMATCH)
{
c = *p; *p = '\0';
ret = savestring (param);
*p = c;
return (ret);
}
}
break;
}
return (savestring (param)); /* no match, return original string */
}
/* Return 1 of the first character of STRING could match the first
character of pattern PAT. Used to avoid n2 calls to fnmatch(). */
static int
match_pattern_char (pat, string)
char *pat, *string;
{
char c;
if (*string == 0)
return (0);
switch (c = *pat++)
{
default:
return (*string == c);
case '\\':
return (*string == *pat);
case '?':
return (*string == LPAREN ? 1 : (*string != '\0'));
case '*':
return (1);
case '+':
case '!':
case '@':
return (*string == LPAREN ? 1 : (*string == c));
case '[':
return (*string != '\0');
}
}
/* Match PAT anywhere in STRING and return the match boundaries.
This returns 1 in case of a successful match, 0 otherwise. SP
and EP are pointers into the string where the match begins and
ends, respectively. MTYPE controls what kind of match is attempted.
MATCH_BEG and MATCH_END anchor the match at the beginning and end
of the string, respectively. The longest match is returned. */
static int
match_pattern (string, pat, mtype, sp, ep)
char *string, *pat;
int mtype;
char **sp, **ep;
{
int c;
register char *p, *p1;
char *end;
if (string == 0 || *string == 0 || pat == 0 || *pat == 0)
return (0);
end = string + STRLEN (string);
switch (mtype)
{
case MATCH_ANY:
for (p = string; p <= end; p++)
{
if (match_pattern_char (pat, p))
{
for (p1 = end; p1 >= p; p1--)
{
c = *p1; *p1 = '\0';
if (fnmatch (pat, p, FNMATCH_EXTFLAG) == 0)
{
*p1 = c;
*sp = p;
*ep = p1;
return 1;
}
*p1 = c;
}
}
}
return (0);
case MATCH_BEG:
if (match_pattern_char (pat, string) == 0)
return (0);
for (p = end; p >= string; p--)
{
c = *p; *p = '\0';
if (fnmatch (pat, string, FNMATCH_EXTFLAG) == 0)
{
*p = c;
*sp = string;
*ep = p;
return 1;
}
*p = c;
}
return (0);
case MATCH_END:
for (p = string; p <= end; p++)
if (fnmatch (pat, p, FNMATCH_EXTFLAG) == 0)
{
*sp = p;
*ep = end;
return 1;
}
return (0);
}
return (0);
}
static int
getpatspec (c, value)
int c;
char *value;
{
if (c == '#')
return ((*value == '#') ? RP_LONG_LEFT : RP_SHORT_LEFT);
else /* c == '%' */
return ((*value == '%') ? RP_LONG_RIGHT : RP_SHORT_RIGHT);
}
/* Posix.2 says that the WORD should be run through tilde expansion,
parameter expansion, command substitution and arithmetic expansion.
This leaves the result quoted, so quote_string_for_globbing () has
to be called to fix it up for fnmatch (). If QUOTED is non-zero,
it means that the entire expression was enclosed in double quotes.
This means that quoting characters in the pattern do not make any
special pattern characters quoted. For example, the `*' in the
following retains its special meaning: "${foo#'*'}". */
static char *
getpattern (value, quoted, expandpat)
char *value;
int quoted, expandpat;
{
char *pat, *tword;
WORD_LIST *l;
int i;
tword = strchr (value, '~') ? bash_tilde_expand (value) : savestring (value);
/* expand_string_internal () leaves WORD quoted and does not perform
word splitting. */
if (expandpat && (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) && *tword)
{
i = 0;
pat = string_extract_double_quoted (tword, &i, 1);
free (tword);
tword = pat;
}
/* There is a problem here: how to handle single or double quotes in the
pattern string when the whole expression is between double quotes? */
#if 0
l = *tword ? expand_string_for_rhs (tword, quoted, (int *)NULL, (int *)NULL)
#else
l = *tword ? expand_string_for_rhs (tword,
(quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) ? Q_NOQUOTE : quoted,
(int *)NULL, (int *)NULL)
#endif
: (WORD_LIST *)0;
free (tword);
pat = string_list (l);
dispose_words (l);
if (pat)
{
tword = quote_string_for_globbing (pat, QGLOB_CVTNULL);
free (pat);
pat = tword;
}
return (pat);
}
/* Handle removing a pattern from a string as a result of ${name%[%]value}
or ${name#[#]value}. */
static char *
parameter_brace_remove_pattern (value, temp, c, quoted)
char *value, *temp;
int c, quoted;
{
int patspec;
char *pattern, *tword;
patspec = getpatspec (c, value);
if (patspec == RP_LONG_LEFT || patspec == RP_LONG_RIGHT)
value++;
pattern = getpattern (value, quoted, 1);
tword = remove_pattern (temp, pattern, patspec);
FREE (pattern);
return (tword);
}
static char *
list_remove_pattern (list, pattern, patspec, type, quoted)
WORD_LIST *list;
char *pattern;
int patspec, type, quoted;
{
WORD_LIST *new, *l;
WORD_DESC *w;
char *tword;
for (new = (WORD_LIST *)NULL, l = list; l; l = l->next)
{
tword = remove_pattern (l->word->word, pattern, patspec);
w = make_bare_word (tword);
free (tword);
new = make_word_list (w, new);
}
l = REVERSE_LIST (new, WORD_LIST *);
if (type == '*')
tword = (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) ? string_list_dollar_star (l) : string_list (l);
else
tword = string_list ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) ? quote_list (l) : l);
dispose_words (l);
return (tword);
}
static char *
parameter_list_remove_pattern (value, type, c, quoted)
char *value;
int type, c, quoted;
{
int patspec;
char *pattern, *ret;
WORD_LIST *list;
patspec = getpatspec (c, value);
if (patspec == RP_LONG_LEFT || patspec == RP_LONG_RIGHT)
value++;
pattern = getpattern (value, quoted, 1);
list = list_rest_of_args ();
ret = list_remove_pattern (list, pattern, patspec, type, quoted);
dispose_words (list);
FREE (pattern);
return (ret);
}
#if defined (ARRAY_VARS)
static char *
array_remove_pattern (value, aspec, aval, c, quoted)
char *value, *aspec, *aval; /* AVAL == evaluated ASPEC */
int c, quoted;
{
SHELL_VAR *var;
int len, patspec;
char *ret, *t, *pattern;
WORD_LIST *l;
var = array_variable_part (aspec, &t, &len);
if (var == 0)
return ((char *)NULL);
patspec = getpatspec (c, value);
if (patspec == RP_LONG_LEFT || patspec == RP_LONG_RIGHT)
value++;
pattern = getpattern (value, quoted, 1);
if (ALL_ELEMENT_SUB (t[0]) && t[1] == ']')
{
if (array_p (var) == 0)
{
report_error ("%s: bad array subscript", aspec);
FREE (pattern);
return ((char *)NULL);
}
l = array_to_word_list (array_cell (var));
if (l == 0)
return ((char *)NULL);
ret = list_remove_pattern (l, pattern, patspec, t[0], quoted);
dispose_words (l);
}
else
{
ret = remove_pattern (aval, pattern, patspec);
if (ret)
{
t = quote_escapes (ret);
free (ret);
ret = t;
}
}
FREE (pattern);
return ret;
}
#endif /* ARRAY_VARS */
/*******************************************
* *
* Functions to expand WORD_DESCs *
* *
*******************************************/
/* Expand WORD, performing word splitting on the result. This does
parameter expansion, command substitution, arithmetic expansion,
word splitting, and quote removal. */
WORD_LIST *
expand_word (word, quoted)
WORD_DESC *word;
int quoted;
{
WORD_LIST *result, *tresult;
tresult = call_expand_word_internal (word, quoted, 0, (int *)NULL, (int *)NULL);
result = word_list_split (tresult);
dispose_words (tresult);
return (result ? dequote_list (result) : result);
}
/* Expand WORD, but do not perform word splitting on the result. This
does parameter expansion, command substitution, arithmetic expansion,
and quote removal. */
WORD_LIST *
expand_word_no_split (word, quoted)
WORD_DESC *word;
int quoted;
{
WORD_LIST *result;
result = call_expand_word_internal (word, quoted, 0, (int *)NULL, (int *)NULL);
return (result ? dequote_list (result) : result);
}
/* Perform shell expansions on WORD, but do not perform word splitting or
quote removal on the result. */
WORD_LIST *
expand_word_leave_quoted (word, quoted)
WORD_DESC *word;
int quoted;
{
return (call_expand_word_internal (word, quoted, 0, (int *)NULL, (int *)NULL));
}
#if defined (PROCESS_SUBSTITUTION)
/*****************************************************************/
/* */
/* Hacking Process Substitution */
/* */
/*****************************************************************/
#if !defined (HAVE_DEV_FD)
/* Named pipes must be removed explicitly with `unlink'. This keeps a list
of FIFOs the shell has open. unlink_fifo_list will walk the list and
unlink all of them. add_fifo_list adds the name of an open FIFO to the
list. NFIFO is a count of the number of FIFOs in the list. */
#define FIFO_INCR 20
extern char *mktemp ();
static char **fifo_list = (char **)NULL;
static int nfifo;
static int fifo_list_size;
static void
add_fifo_list (pathname)
char *pathname;
{
if (nfifo >= fifo_list_size - 1)
{
fifo_list_size += FIFO_INCR;
fifo_list = (char **)xrealloc (fifo_list,
fifo_list_size * sizeof (char *));
}
fifo_list[nfifo++] = savestring (pathname);
}
void
unlink_fifo_list ()
{
if (nfifo == 0)
return;
while (nfifo--)
{
unlink (fifo_list[nfifo]);
free (fifo_list[nfifo]);
fifo_list[nfifo] = (char *)NULL;
}
nfifo = 0;
}
static char *
make_named_pipe ()
{
char *tname;
tname = mktemp (savestring ("/tmp/sh-np-XXXXXX"));
if (mkfifo (tname, 0600) < 0)
{
free (tname);
return ((char *)NULL);
}
add_fifo_list (tname);
return (tname);
}
#else /* HAVE_DEV_FD */
/* DEV_FD_LIST is a bitmap of file descriptors attached to pipes the shell
has open to children. NFDS is a count of the number of bits currently
set in DEV_FD_LIST. TOTFDS is a count of the highest possible number
of open files. */
static char *dev_fd_list = (char *)NULL;
static int nfds;
static int totfds; /* The highest possible number of open files. */
static void
add_fifo_list (fd)
int fd;
{
if (!dev_fd_list || fd >= totfds)
{
int ofds;
ofds = totfds;
totfds = getdtablesize ();
if (totfds < 0 || totfds > 256)
totfds = 256;
if (fd > totfds)
totfds = fd + 2;
dev_fd_list = xrealloc (dev_fd_list, totfds);
bzero (dev_fd_list + ofds, totfds - ofds);
}
dev_fd_list[fd] = 1;
nfds++;
}
void
unlink_fifo_list ()
{
register int i;
if (nfds == 0)
return;
for (i = 0; nfds && i < totfds; i++)
if (dev_fd_list[i])
{
close (i);
dev_fd_list[i] = 0;
nfds--;
}
nfds = 0;
}
#if defined (NOTDEF)
print_dev_fd_list ()
{
register int i;
fprintf (stderr, "pid %d: dev_fd_list:", getpid ());
fflush (stderr);
for (i = 0; i < totfds; i++)
{
if (dev_fd_list[i])
fprintf (stderr, " %d", i);
}
fprintf (stderr, "\n");
}
#endif /* NOTDEF */
static char *
make_dev_fd_filename (fd)
int fd;
{
char *ret, intbuf[16], *p;
ret = xmalloc (sizeof (DEV_FD_PREFIX) + 4);
strcpy (ret, DEV_FD_PREFIX);
p = inttostr (fd, intbuf, sizeof (intbuf));
strcpy (ret + sizeof (DEV_FD_PREFIX) - 1, p);
add_fifo_list (fd);
return (ret);
}
#endif /* HAVE_DEV_FD */
/* Return a filename that will open a connection to the process defined by
executing STRING. HAVE_DEV_FD, if defined, means open a pipe and return
a filename in /dev/fd corresponding to a descriptor that is one of the
ends of the pipe. If not defined, we use named pipes on systems that have
them. Systems without /dev/fd and named pipes are out of luck.
OPEN_FOR_READ_IN_CHILD, if 1, means open the named pipe for reading or
use the read end of the pipe and dup that file descriptor to fd 0 in
the child. If OPEN_FOR_READ_IN_CHILD is 0, we open the named pipe for
writing or use the write end of the pipe in the child, and dup that
file descriptor to fd 1 in the child. The parent does the opposite. */
static char *
process_substitute (string, open_for_read_in_child)
char *string;
int open_for_read_in_child;
{
char *pathname;
int fd, result;
pid_t old_pid, pid;
#if defined (HAVE_DEV_FD)
int parent_pipe_fd, child_pipe_fd;
int fildes[2];
#endif /* HAVE_DEV_FD */
#if defined (JOB_CONTROL)
pid_t old_pipeline_pgrp;
#endif
if (!string || !*string || wordexp_only)
return ((char *)NULL);
#if !defined (HAVE_DEV_FD)
pathname = make_named_pipe ();
#else /* HAVE_DEV_FD */
if (pipe (fildes) < 0)
{
sys_error ("cannot make pipe for process substitution");
return ((char *)NULL);
}
/* If OPEN_FOR_READ_IN_CHILD == 1, we want to use the write end of
the pipe in the parent, otherwise the read end. */
parent_pipe_fd = fildes[open_for_read_in_child];
child_pipe_fd = fildes[1 - open_for_read_in_child];
/* Move the parent end of the pipe to some high file descriptor, to
avoid clashes with FDs used by the script. */
parent_pipe_fd = move_to_high_fd (parent_pipe_fd, 1, 64);
pathname = make_dev_fd_filename (parent_pipe_fd);
#endif /* HAVE_DEV_FD */
if (!pathname)
{
sys_error ("cannot make pipe for process substitution");
return ((char *)NULL);
}
old_pid = last_made_pid;
#if defined (JOB_CONTROL)
old_pipeline_pgrp = pipeline_pgrp;
pipeline_pgrp = shell_pgrp;
#if 0
cleanup_the_pipeline ();
#else
save_pipeline (1);
#endif
#endif /* JOB_CONTROL */
pid = make_child ((char *)NULL, 1);
if (pid == 0)
{
reset_terminating_signals (); /* XXX */
/* Cancel traps, in trap.c. */
restore_original_signals ();
setup_async_signals ();
subshell_environment = SUBSHELL_COMSUB;
}
#if defined (JOB_CONTROL)
set_sigchld_handler ();
stop_making_children ();
pipeline_pgrp = old_pipeline_pgrp;
#endif /* JOB_CONTROL */
if (pid < 0)
{
sys_error ("cannot make child for process substitution");
free (pathname);
#if defined (HAVE_DEV_FD)
close (parent_pipe_fd);
close (child_pipe_fd);
#endif /* HAVE_DEV_FD */
return ((char *)NULL);
}
if (pid > 0)
{
#if defined (JOB_CONTROL)
restore_pipeline (1);
#endif
last_made_pid = old_pid;
#if defined (JOB_CONTROL) && defined (PGRP_PIPE)
close_pgrp_pipe ();
#endif /* JOB_CONTROL && PGRP_PIPE */
#if defined (HAVE_DEV_FD)
close (child_pipe_fd);
#endif /* HAVE_DEV_FD */
return (pathname);
}
set_sigint_handler ();
#if defined (JOB_CONTROL)
set_job_control (0);
#endif /* JOB_CONTROL */
#if !defined (HAVE_DEV_FD)
/* Open the named pipe in the child. */
fd = open (pathname, open_for_read_in_child ? O_RDONLY|O_NONBLOCK : O_WRONLY);
if (fd < 0)
{
sys_error ("cannot open named pipe %s for %s", pathname,
open_for_read_in_child ? "reading" : "writing");
exit (127);
}
if (open_for_read_in_child)
{
if (unset_nodelay_mode (fd) < 0)
{
sys_error ("cannout reset nodelay mode for fd %d", fd);
exit (127);
}
}
#else /* HAVE_DEV_FD */
fd = child_pipe_fd;
#endif /* HAVE_DEV_FD */
if (dup2 (fd, open_for_read_in_child ? 0 : 1) < 0)
{
sys_error ("cannot duplicate named pipe %s as fd %d", pathname,
open_for_read_in_child ? 0 : 1);
exit (127);
}
close (fd);
/* Need to close any files that this process has open to pipes inherited
from its parent. */
if (current_fds_to_close)
{
close_fd_bitmap (current_fds_to_close);
current_fds_to_close = (struct fd_bitmap *)NULL;
}
#if defined (HAVE_DEV_FD)
/* Make sure we close the parent's end of the pipe and clear the slot
in the fd list so it is not closed later, if reallocated by, for
instance, pipe(2). */
close (parent_pipe_fd);
dev_fd_list[parent_pipe_fd] = 0;
#endif /* HAVE_DEV_FD */
result = parse_and_execute (string, "process substitution", (SEVAL_NONINT|SEVAL_NOHIST));
#if !defined (HAVE_DEV_FD)
/* Make sure we close the named pipe in the child before we exit. */
close (open_for_read_in_child ? 0 : 1);
#endif /* !HAVE_DEV_FD */
exit (result);
/*NOTREACHED*/
}
#endif /* PROCESS_SUBSTITUTION */
/***********************************/
/* */
/* Command Substitution */
/* */
/***********************************/
static char *
read_comsub (fd, quoted)
int fd, quoted;
{
char *istring, buf[128], *bufp;
int bufn, istring_index, istring_size, c;
istring = (char *)NULL;
istring_index = istring_size = bufn = 0;
/* Read the output of the command through the pipe. */
while (1)
{
if (fd < 0)
break;
if (--bufn <= 0)
{
bufn = zread (fd, buf, sizeof (buf));
if (bufn <= 0)
break;
bufp = buf;
}
c = *bufp++;
/* Add the character to ISTRING, possibly after resizing it. */
RESIZE_MALLOCED_BUFFER (istring, istring_index, 2, istring_size, DEFAULT_ARRAY_SIZE);
if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) || c == CTLESC || c == CTLNUL)
istring[istring_index++] = CTLESC;
istring[istring_index++] = c;
}
if (istring)
istring[istring_index] = '\0';
/* If we read no output, just return now and save ourselves some
trouble. */
if (istring_index == 0)
{
FREE (istring);
return (char *)NULL;
}
/* Strip trailing newlines from the output of the command. */
if (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES))
{
while (istring_index > 0)
{
if (istring[istring_index - 1] == '\n')
{
--istring_index;
/* If the newline was quoted, remove the quoting char. */
if (istring[istring_index - 1] == CTLESC)
--istring_index;
}
else
break;
}
istring[istring_index] = '\0';
}
else
strip_trailing (istring, istring_index - 1, 1);
return istring;
}
/* Perform command substitution on STRING. This returns a string,
possibly quoted. */
char *
command_substitute (string, quoted)
char *string;
int quoted;
{
pid_t pid, old_pid, old_pipeline_pgrp;
char *istring;
int result, fildes[2], function_value;
istring = (char *)NULL;
/* Don't fork () if there is no need to. In the case of no command to
run, just return NULL. */
if (!string || !*string || (string[0] == '\n' && !string[1]))
return ((char *)NULL);
if (wordexp_only && read_but_dont_execute)
{
last_command_exit_value = 125;
jump_to_top_level (EXITPROG);
}
/* We're making the assumption here that the command substitution will
eventually run a command from the file system. Since we'll run
maybe_make_export_env in this subshell before executing that command,
the parent shell and any other shells it starts will have to remake
the environment. If we make it before we fork, other shells won't
have to. Don't bother if we have any temporary variable assignments,
though, because the export environment will be remade after this
command completes anyway, but do it if all the words to be expanded
are variable assignments. */
if (subst_assign_varlist == 0 || garglist == 0)
maybe_make_export_env (); /* XXX */
/* Pipe the output of executing STRING into the current shell. */
if (pipe (fildes) < 0)
{
sys_error ("cannot make pipes for command substitution");
goto error_exit;
}
old_pid = last_made_pid;
#if defined (JOB_CONTROL)
old_pipeline_pgrp = pipeline_pgrp;
pipeline_pgrp = shell_pgrp;
cleanup_the_pipeline ();
#endif
pid = make_child ((char *)NULL, 0);
if (pid == 0)
/* Reset the signal handlers in the child, but don't free the
trap strings. */
reset_signal_handlers ();
#if defined (JOB_CONTROL)
set_sigchld_handler ();
stop_making_children ();
pipeline_pgrp = old_pipeline_pgrp;
#endif /* JOB_CONTROL */
if (pid < 0)
{
sys_error ("cannot make child for command substitution");
error_exit:
FREE (istring);
close (fildes[0]);
close (fildes[1]);
return ((char *)NULL);
}
if (pid == 0)
{
set_sigint_handler (); /* XXX */
#if 0
#if defined (JOB_CONTROL)
set_job_control (0);
#endif
#endif
if (dup2 (fildes[1], 1) < 0)
{
sys_error ("command_substitute: cannot duplicate pipe as fd 1");
exit (EXECUTION_FAILURE);
}
/* If standard output is closed in the parent shell
(such as after `exec >&-'), file descriptor 1 will be
the lowest available file descriptor, and end up in
fildes[0]. This can happen for stdin and stderr as well,
but stdout is more important -- it will cause no output
to be generated from this command. */
if ((fildes[1] != fileno (stdin)) &&
(fildes[1] != fileno (stdout)) &&
(fildes[1] != fileno (stderr)))
close (fildes[1]);
if ((fildes[0] != fileno (stdin)) &&
(fildes[0] != fileno (stdout)) &&
(fildes[0] != fileno (stderr)))
close (fildes[0]);
/* The currently executing shell is not interactive. */
interactive = 0;
/* This is a subshell environment. */
subshell_environment = SUBSHELL_COMSUB;
/* Command substitution does not inherit the -e flag. */
exit_immediately_on_error = 0;
remove_quoted_escapes (string);
startup_state = 2; /* see if we can avoid a fork */
/* Give command substitution a place to jump back to on failure,
so we don't go back up to main (). */
result = setjmp (top_level);
/* If we're running a command substitution inside a shell function,
trap `return' so we don't return from the function in the subshell
and go off to never-never land. */
if (result == 0 && return_catch_flag)
function_value = setjmp (return_catch);
else
function_value = 0;
if (result == EXITPROG)
exit (last_command_exit_value);
else if (result)
exit (EXECUTION_FAILURE);
else if (function_value)
exit (return_catch_value);
else
exit (parse_and_execute (string, "command substitution", SEVAL_NOHIST));
}
else
{
#if defined (JOB_CONTROL) && defined (PGRP_PIPE)
close_pgrp_pipe ();
#endif /* JOB_CONTROL && PGRP_PIPE */
close (fildes[1]);
istring = read_comsub (fildes[0], quoted);
close (fildes[0]);
current_command_subst_pid = pid;
last_command_exit_value = wait_for (pid);
last_command_subst_pid = pid;
last_made_pid = old_pid;
#if defined (JOB_CONTROL)
/* If last_command_exit_value > 128, then the substituted command
was terminated by a signal. If that signal was SIGINT, then send
SIGINT to ourselves. This will break out of loops, for instance. */
if (last_command_exit_value == (128 + SIGINT))
kill (getpid (), SIGINT);
/* wait_for gives the terminal back to shell_pgrp. If some other
process group should have it, give it away to that group here.
pipeline_pgrp is non-zero only while we are constructing a
pipline, so what we are concerned about is whether or not that
pipeline was started in the background. A pipeline started in
the background should never get the tty back here. */
#if 0
if (interactive && pipeline_pgrp != (pid_t)0 && pipeline_pgrp != last_asynchronous_pid)
#else
if (interactive && pipeline_pgrp != (pid_t)0 && subshell_environment != SUBSHELL_ASYNC)
#endif
give_terminal_to (pipeline_pgrp);
#endif /* JOB_CONTROL */
return (istring);
}
}
/********************************************************
* *
* Utility functions for parameter expansion *
* *
********************************************************/
/* Utility functions to manage arrays and their contents for expansion */
#if defined (ARRAY_VARS)
int
valid_array_reference (name)
char *name;
{
char *t;
int r, len;
t = strchr (name, '[');
if (t)
{
*t = '\0';
r = legal_identifier (name);
*t = '[';
if (r == 0)
return 0;
/* Check for a properly-terminated non-blank subscript. */
len = skipsubscript (t, 0);
if (t[len] != ']' || len == 1)
return 0;
for (r = 1; r < len; r++)
if (whitespace (t[r]) == 0)
return 1;
return 0;
}
return 0;
}
/* Expand the array index beginning at S and extending LEN characters. */
int
array_expand_index (s, len)
char *s;
int len;
{
char *exp, *t;
int val, expok;
exp = xmalloc (len);
strncpy (exp, s, len - 1);
exp[len - 1] = '\0';
t = maybe_expand_string (exp, 0, expand_string);
this_command_name = (char *)NULL;
val = evalexp (t, &expok);
free (t);
free (exp);
if (expok == 0)
jump_to_top_level (DISCARD);
return val;
}
/* Return the variable specified by S without any subscript. If non-null,
return the index of the start of the subscript in *SUBP. If non-null,
the length of the subscript is returned in *LENP. */
SHELL_VAR *
array_variable_part (s, subp, lenp)
char *s, **subp;
int *lenp;
{
char *t;
int ind, ni;
SHELL_VAR *var;
t = strchr (s, '[');
ind = t - s;
ni = skipsubscript (s, ind);
if (ni <= ind + 1 || s[ni] != ']')
{
report_error ("%s: bad array subscript", s);
return ((SHELL_VAR *)NULL);
}
*t = '\0';
var = find_variable (s);
*t++ = '[';
if (subp)
*subp = t;
if (lenp)
*lenp = ni - ind;
return var;
}
static char *
array_value_internal (s, quoted, allow_all)
char *s;
int quoted, allow_all;
{
int len, ind;
char *retval, *t, *temp;
WORD_LIST *l, *list;
SHELL_VAR *var;
var = array_variable_part (s, &t, &len);
if (var == 0)
return (char *)NULL;
if (ALL_ELEMENT_SUB (t[0]) && t[1] == ']')
{
if (array_p (var) == 0 || allow_all == 0)
{
report_error ("%s: bad array subscript", s);
return ((char *)NULL);
}
l = array_to_word_list (array_cell (var));
if (l == (WORD_LIST *)NULL)
return ((char *) NULL);
#if 0
if (t[0] == '*') /* ${name[*]} */
retval = (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) ? string_list_dollar_star (l) : string_list (l);
else /* ${name[@]} */
retval = string_list ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) ? quote_list (l) : l);
#else
if (t[0] == '*' && (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)))
{
temp = string_list_dollar_star (l);
retval = quote_string (temp);
free (temp);
}
else /* ${name[@]} or unquoted ${name[*]} */
retval = string_list_dollar_at (l, quoted);
#endif
dispose_words (l);
}
else
{
ind = array_expand_index (t, len);
if (ind < 0)
{
report_error ("%s: bad array subscript", var->name);
return ((char *)NULL);
}
if (array_p (var) == 0)
return (ind == 0 ? savestring (value_cell (var)) : (char *)NULL);
retval = array_reference (array_cell (var), ind);
if (retval)
retval = quote_escapes (retval);
}
return retval;
}
static char *
array_value (s, quoted)
char *s;
int quoted;
{
return (array_value_internal (s, quoted, 1));
}
/* Return the value of the array indexing expression S as a single string.
If ALLOW_ALL is 0, do not allow `@' and `*' subscripts. This is used
by other parts of the shell such as the arithmetic expression evaluator
in expr.c. */
char *
get_array_value (s, allow_all)
char *s;
int allow_all;
{
return (array_value_internal (s, 0, allow_all));
}
static int
array_length_reference (s)
char *s;
{
int ind, len;
char *t;
ARRAY *array;
SHELL_VAR *var;
var = array_variable_part (s, &t, &len);
/* If unbound variables should generate an error, report one and return
failure. */
if ((var == 0 || array_p (var) == 0) && unbound_vars_is_error)
{
ind = *--t;
*t = '\0';
report_error ("%s: unbound variable", s);
*t++ = (char)ind;
return (-1);
}
else if (var == 0)
return 0;
else if (array_p (var) == 0)
return 1;
array = array_cell (var);
if (ALL_ELEMENT_SUB (t[0]) && t[1] == ']')
return (array_num_elements (array));
ind = array_expand_index (t, len);
if (ind < 0)
{
report_error ("%s: bad array subscript", t);
return (-1);
}
t = array_reference (array, ind);
len = STRLEN (t);
return (len);
}
#endif /* ARRAY_VARS */
static int
valid_brace_expansion_word (name, var_is_special)
char *name;
int var_is_special;
{
if (digit (*name) && all_digits (name))
return 1;
else if (var_is_special)
return 1;
#if defined (ARRAY_VARS)
else if (valid_array_reference (name))
return 1;
#endif /* ARRAY_VARS */
else if (legal_identifier (name))
return 1;
else
return 0;
}
/* Parameter expand NAME, and return a new string which is the expansion,
or NULL if there was no expansion.
VAR_IS_SPECIAL is non-zero if NAME is one of the special variables in
the shell, e.g., "@", "$", "*", etc. QUOTED, if non-zero, means that
NAME was found inside of a double-quoted expression. */
static char *
parameter_brace_expand_word (name, var_is_special, quoted)
char *name;
int var_is_special, quoted;
{
char *temp, *tt;
int arg_index;
SHELL_VAR *var;
WORD_LIST *l;
/* Handle multiple digit arguments, as in ${11}. */
if (digit (*name))
{
arg_index = atoi (name);
temp = get_dollar_var_value (arg_index);
}
else if (var_is_special) /* ${@} */
{
int sindex;
tt = xmalloc (2 + strlen (name));
tt[sindex = 0] = '$';
strcpy (tt + 1, name);
#if 0
l = expand_string_leave_quoted (tt, quoted);
free (tt);
temp = string_list (l);
dispose_words (l);
#else
temp = param_expand (tt, &sindex, quoted, (int *)NULL, (int *)NULL,
(int *)NULL, (int *)NULL, 0);
free (tt);
#endif
}
#if defined (ARRAY_VARS)
else if (valid_array_reference (name))
{
temp = array_value (name, quoted);
}
#endif
else if (var = find_variable (name))
{
if (var && invisible_p (var) == 0)
{
#if defined (ARRAY_VARS)
temp = array_p (var) ? array_reference (array_cell (var), 0) : value_cell (var);
#else
temp = value_cell (var);
#endif
if (temp)
temp = quote_escapes (temp);
if (tempvar_p (var))
dispose_variable (var);
}
else
temp = (char *)NULL;
}
else
temp = (char *)NULL;
return (temp);
}
/* Expand an indirect reference to a variable: ${!NAME} expands to the
value of the variable whose name is the value of NAME. */
static char *
parameter_brace_expand_indir (name, var_is_special, quoted)
char *name;
int var_is_special, quoted;
{
char *temp, *t;
t = parameter_brace_expand_word (name, var_is_special, quoted);
if (t == 0)
return (t);
#if 0
temp = parameter_brace_expand_word (t, t[0] == '@' && t[1] == '\0', quoted);
#else
temp = parameter_brace_expand_word (t, SPECIAL_VAR(t, 0), quoted);
#endif
free (t);
return temp;
}
/* Expand the right side of a parameter expansion of the form ${NAMEcVALUE},
depending on the value of C, the separating character. C can be one of
"-", "+", or "=". QUOTED is true if the entire brace expression occurs
between double quotes. */
static char *
parameter_brace_expand_rhs (name, value, c, quoted, qdollaratp, hasdollarat)
char *name, *value;
int c, quoted, *qdollaratp, *hasdollarat;
{
WORD_LIST *l;
char *t, *t1, *temp;
int hasdol;
temp = (*value == '~' || (strchr (value, '~') && unquoted_substring ("=~", value)))
? bash_tilde_expand (value)
: savestring (value);
/* If the entire expression is between double quotes, we want to treat
the value as a double-quoted string, with the exception that we strip
embedded unescaped double quotes. */
if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) && *temp)
{
hasdol = 0;
t = string_extract_double_quoted (temp, &hasdol, 1);
free (temp);
temp = t;
}
hasdol = 0;
/* XXX was 0 not quoted */
l = *temp ? expand_string_for_rhs (temp, quoted, &hasdol, (int *)NULL)
: (WORD_LIST *)0;
if (hasdollarat)
*hasdollarat = hasdol || (l && l->next);
free (temp);
if (l)
{
/* The expansion of TEMP returned something. We need to treat things
slightly differently if HASDOL is non-zero. */
temp = string_list (l);
/* If l->next is not null, we know that TEMP contained "$@", since that
is the only expansion that creates more than one word. */
if ((hasdol && quoted) || l->next)
*qdollaratp = 1;
dispose_words (l);
}
else if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) && hasdol)
{
/* The brace expansion occurred between double quotes and there was
a $@ in TEMP. It does not matter if the $@ is quoted, as long as
it does not expand to anything. In this case, we want to return
a quoted empty string. */
temp = xmalloc (2);
temp[0] = CTLNUL;
temp[1] = '\0';
}
else
temp = (char *)NULL;
if (c == '-' || c == '+')
return (temp);
/* c == '=' */
t = temp ? savestring (temp) : savestring ("");
t1 = dequote_string (t);
free (t);
bind_variable (name, t1);
free (t1);
return (temp);
}
/* Deal with the right hand side of a ${name:?value} expansion in the case
that NAME is null or not set. If VALUE is non-null it is expanded and
used as the error message to print, otherwise a standard message is
printed. */
static void
parameter_brace_expand_error (name, value)
char *name, *value;
{
WORD_LIST *l;
char *temp;
if (value && *value)
{
l = expand_string (value, 0);
temp = string_list (l);
report_error ("%s: %s", name, temp ? temp : ""); /* XXX was value not "" */
FREE (temp);
dispose_words (l);
}
else
report_error ("%s: parameter null or not set", name);
/* Free the data we have allocated during this expansion, since we
are about to longjmp out. */
free (name);
FREE (value);
}
/* Return 1 if NAME is something for which parameter_brace_expand_length is
OK to do. */
static int
valid_length_expression (name)
char *name;
{
return (!name[1] || /* ${#} */
((name[1] == '@' || name[1] == '*') && !name[2]) || /* ${#@}, ${#*} */
(member (name[1], "-?$!#") && !name[2]) || /* ${#-}, etc. */
(digit (name[1]) && all_digits (name + 1)) || /* ${#11} */
#if defined (ARRAY_VARS)
valid_array_reference (name + 1) || /* ${#a[7]} */
#endif
legal_identifier (name + 1)); /* ${#PS1} */
}
/* Handle the parameter brace expansion that requires us to return the
length of a parameter. */
static int
parameter_brace_expand_length (name)
char *name;
{
char *t, *newname;
int number;
WORD_LIST *list;
#if defined (ARRAY_VARS)
SHELL_VAR *var;
#endif
if (name[1] == '\0') /* ${#} */
number = number_of_args ();
else if ((name[1] == '@' || name[1] == '*') && name[2] == '\0') /* ${#@}, ${#*} */
number = number_of_args ();
else if (member (name[1], "-?$!#") && name[2] == '\0')
{
/* Take the lengths of some of the shell's special parameters. */
switch (name[1])
{
case '-':
t = which_set_flags ();
break;
case '?':
t = itos (last_command_exit_value);
break;
case '$':
t = itos (dollar_dollar_pid);
break;
case '!':
if (last_asynchronous_pid == NO_PID)
t = (char *)NULL;
else
t = itos ((int)last_asynchronous_pid);
break;
case '#':
t = itos (number_of_args ());
break;
}
number = STRLEN (t);
FREE (t);
}
#if defined (ARRAY_VARS)
else if (valid_array_reference (name + 1))
number = array_length_reference (name + 1);
#endif /* ARRAY_VARS */
else
{
number = 0;
if (digit (name[1])) /* ${#1} */
{
t = get_dollar_var_value (atoi (name + 1));
number = STRLEN (t);
FREE (t);
}
#if defined (ARRAY_VARS)
else if ((var = find_variable (name + 1)) && array_p (var))
{
t = array_reference (array_cell (var), 0);
number = STRLEN (t);
}
#endif
else /* ${#PS1} */
{
newname = savestring (name);
newname[0] = '$';
list = expand_string (newname, Q_DOUBLE_QUOTES);
t = list ? string_list (list) : (char *)NULL;
free (newname);
if (list)
dispose_words (list);
number = STRLEN (t);
FREE (t);
}
}
return (number);
}
/* Verify and limit the start and end of the desired substring. If
VTYPE == 0, a regular shell variable is being used; if it is 1,
then the positional parameters are being used; if it is 2, then
VALUE is really a pointer to an array variable that should be used.
Return value is 1 if both values were OK, 0 if there was a problem
with an invalid expression, or -1 if the values were out of range. */
static int
verify_substring_values (value, substr, vtype, e1p, e2p)
char *value, *substr;
int vtype, *e1p, *e2p;
{
char *t, *temp1, *temp2;
int len, expok;
#if defined (ARRAY_VARS)
ARRAY *a;
#endif
t = strchr (substr, ':');
if (t)
*t = '\0';
temp1 = maybe_expand_string (substr, Q_DOUBLE_QUOTES, expand_string);
*e1p = evalexp (temp1, &expok);
free (temp1);
if (expok == 0)
return (0);
switch (vtype)
{
case VT_VARIABLE:
case VT_ARRAYMEMBER:
len = strlen (value);
break;
case VT_POSPARMS:
len = number_of_args () + 1;
break;
#if defined (ARRAY_VARS)
case VT_ARRAYVAR:
a = (ARRAY *)value;
len = array_num_elements (a) + 1;
break;
#endif
}
if (*e1p < 0) /* negative offsets count from end */
*e1p += len;
if (*e1p >= len || *e1p < 0)
return (-1);
if (t)
{
t++;
temp2 = savestring (t);
temp1 = maybe_expand_string (temp2, Q_DOUBLE_QUOTES, expand_string);
free (temp2);
t[-1] = ':';
*e2p = evalexp (temp1, &expok);
free (temp1);
if (expok == 0)
return (0);
if (*e2p < 0)
{
internal_error ("%s: substring expression < 0", t);
return (0);
}
*e2p += *e1p; /* want E2 chars starting at E1 */
if (*e2p > len)
*e2p = len;
}
else
*e2p = len;
return (1);
}
/* Return the type of variable specified by VARNAME (simple variable,
positional param, or array variable). Also return the value specified
by VARNAME (value of a variable or a reference to an array element). */
static int
get_var_and_type (varname, value, varp, valp)
char *varname, *value;
SHELL_VAR **varp;
char **valp;
{
int vtype;
char *temp;
#if defined (ARRAY_VARS)
SHELL_VAR *v;
#endif
vtype = (varname[0] == '@' || varname[0] == '*') && varname[1] == '\0'; /* VT_POSPARMS */
*varp = (SHELL_VAR *)NULL;
#if defined (ARRAY_VARS)
if (valid_array_reference (varname))
{
v = array_variable_part (varname, &temp, (int *)0);
if (v && array_p (v))
{
if ((temp[0] == '@' || temp[0] == '*') && temp[1] == ']')
{
vtype = VT_ARRAYVAR;
*valp = (char *)array_cell (v);
}
else
{
vtype = VT_ARRAYMEMBER;
*valp = array_value (varname, 1);
}
*varp = v;
}
else
return -1;
}
else if ((v = find_variable (varname)) && array_p (v))
{
vtype = VT_VARIABLE;
*varp = v;
*valp = array_reference (array_cell (v), 0);
}
else
#endif
*valp = value;
return vtype;
}
/******************************************************/
/* */
/* Functions to extract substrings of variable values */
/* */
/******************************************************/
/* Process a variable substring expansion: ${name:e1[:e2]}. If VARNAME
is `@', use the positional parameters; otherwise, use the value of
VARNAME. If VARNAME is an array variable, use the array elements. */
static char *
parameter_brace_substring (varname, value, substr, quoted)
char *varname, *value, *substr;
int quoted;
{
int e1, e2, vtype, r;
char *temp, *val;
SHELL_VAR *v;
if (value == 0)
return ((char *)NULL);
this_command_name = varname;
vtype = get_var_and_type (varname, value, &v, &val);
if (vtype == -1)
return ((char *)NULL);
r = verify_substring_values (val, substr, vtype, &e1, &e2);
if (r <= 0)
{
if (val && vtype == VT_ARRAYMEMBER)
free (val);
return ((r == 0) ? &expand_param_error : (char *)NULL);
}
switch (vtype)
{
case VT_VARIABLE:
case VT_ARRAYMEMBER:
temp = quoted ? quoted_substring (value, e1, e2) : substring (value, e1, e2);
break;
case VT_POSPARMS:
temp = pos_params (varname, e1, e2, quoted);
break;
#if defined (ARRAY_VARS)
case VT_ARRAYVAR:
temp = array_subrange (array_cell (v), e1, e2, quoted);
break;
#endif
}
return temp;
}
/****************************************************************/
/* */
/* Functions to perform pattern substitution on variable values */
/* */
/****************************************************************/
char *
pat_subst (string, pat, rep, mflags)
char *string, *pat, *rep;
int mflags;
{
char *ret, *s, *e, *str;
int rsize, rptr, l, replen, mtype;
mtype = mflags & MATCH_TYPEMASK;
/* Special cases:
* 1. A null pattern with mtype == MATCH_BEG means to prefix STRING
* with REP and return the result.
* 2. A null pattern with mtype == MATCH_END means to append REP to
* STRING and return the result.
*/
if ((pat == 0 || *pat == 0) && (mtype == MATCH_BEG || mtype == MATCH_END))
{
replen = STRLEN (rep);
l = strlen (string);
ret = xmalloc (replen + l + 2);
if (replen == 0)
strcpy (ret, string);
else if (mtype == MATCH_BEG)
{
strcpy (ret, rep);
strcpy (ret + replen, string);
}
else
{
strcpy (ret, string);
strcpy (ret + l, rep);
}
return (ret);
}
ret = xmalloc (rsize = 64);
ret[0] = '\0';
for (replen = STRLEN (rep), rptr = 0, str = string;;)
{
if (match_pattern (str, pat, mtype, &s, &e) == 0)
break;
l = s - str;
RESIZE_MALLOCED_BUFFER (ret, rptr, (l + replen), rsize, 64);
/* OK, now copy the leading unmatched portion of the string (from
str to s) to ret starting at rptr (the current offset). Then copy
the replacement string at ret + rptr + (s - str). Increment
rptr (if necessary) and str and go on. */
if (l)
{
strncpy (ret + rptr, str, l);
rptr += l;
}
if (replen)
{
strncpy (ret + rptr, rep, replen);
rptr += replen;
}
str = e; /* e == end of match */
if (((mflags & MATCH_GLOBREP) == 0) || mtype != MATCH_ANY)
break;
}
/* Now copy the unmatched portion of the input string */
if (*str)
{
RESIZE_MALLOCED_BUFFER (ret, rptr, STRLEN(str) + 1, rsize, 64);
strcpy (ret + rptr, str);
}
else
ret[rptr] = '\0';
return ret;
}
/* Do pattern match and replacement on the positional parameters. */
static char *
pos_params_pat_subst (string, pat, rep, mflags)
char *string, *pat, *rep;
int mflags;
{
WORD_LIST *save, *params;
WORD_DESC *w;
char *ret;
save = params = list_rest_of_args ();
if (save == 0)
return ((char *)NULL);
for ( ; params; params = params->next)
{
ret = pat_subst (params->word->word, pat, rep, mflags);
w = make_bare_word (ret);
dispose_word (params->word);
params->word = w;
FREE (ret);
}
ret = string_list ((mflags & MATCH_QUOTED) ? quote_list (save) : save);
dispose_words (save);
return (ret);
}
/* Perform pattern substitution on VALUE, which is the expansion of
VARNAME. PATSUB is an expression supplying the pattern to match
and the string to substitute. QUOTED is a flags word containing
the type of quoting currently in effect. */
static char *
parameter_brace_patsub (varname, value, patsub, quoted)
char *varname, *value, *patsub;
int quoted;
{
int vtype, mflags;
char *val, *temp, *pat, *rep, *p, *lpatsub;
SHELL_VAR *v;
if (value == 0)
return ((char *)NULL);
this_command_name = varname;
vtype = get_var_and_type (varname, value, &v, &val);
if (vtype == -1)
return ((char *)NULL);
mflags = 0;
if (*patsub == '/')
{
mflags |= MATCH_GLOBREP;
patsub++;
}
/* Malloc this because maybe_expand_string or one of the expansion functions
in its call chain may free it on a substitution error. */
lpatsub = savestring (patsub);
if (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES))
mflags |= MATCH_QUOTED;
if (rep = quoted_strchr (lpatsub, '/', ST_BACKSL))
*rep++ = '\0';
else
rep = (char *)NULL;
if (rep && *rep == '\0')
rep = (char *)NULL;
/* Expand PAT and REP for command, variable and parameter, arithmetic,
and process substitution. Also perform quote removal. Do not
perform word splitting or filename generation. */
#if 0
pat = maybe_expand_string (lpatsub, quoted, expand_string_unsplit);
#else
pat = maybe_expand_string (lpatsub, (quoted & ~Q_DOUBLE_QUOTES), expand_string_unsplit);
#endif
if (rep)
{
if ((mflags & MATCH_QUOTED) == 0)
rep = maybe_expand_string (rep, quoted, expand_string_unsplit);
else
rep = expand_string_to_string (rep, quoted, expand_string_unsplit);
}
p = pat;
if (pat && pat[0] == '#')
{
mflags |= MATCH_BEG;
p++;
}
else if (pat && pat[0] == '%')
{
mflags |= MATCH_END;
p++;
}
else
mflags |= MATCH_ANY;
/* OK, we now want to substitute REP for PAT in VAL. If
flags & MATCH_GLOBREP is non-zero, the substitution is done
everywhere, otherwise only the first occurrence of PAT is
replaced. */
switch (vtype)
{
case VT_VARIABLE:
case VT_ARRAYMEMBER:
temp = pat_subst (val, p, rep, mflags);
break;
case VT_POSPARMS:
temp = pos_params_pat_subst (val, p, rep, mflags);
break;
#if defined (ARRAY_VARS)
case VT_ARRAYVAR:
temp = array_pat_subst (array_cell (v), p, rep, mflags);
break;
#endif
}
if (val && v && array_p (v) && vtype == VT_ARRAYMEMBER)
free (val);
FREE (pat);
FREE (rep);
free (lpatsub);
return temp;
}
/****************************************************************/
/* */
/* Functions to perform parameter expansion on a string */
/* */
/****************************************************************/
/* ${[#][!]name[[:]#[#]%[%]-=?+[word][:e1[:e2]]]} */
static char *
parameter_brace_expand (string, indexp, quoted, quoted_dollar_atp, contains_dollar_at)
char *string;
int *indexp, quoted, *quoted_dollar_atp, *contains_dollar_at;
{
int check_nullness, var_is_set, var_is_null, var_is_special;
int want_substring, want_indir, want_patsub;
char *name, *value, *temp, *temp1;
int t_index, sindex, c, number;
value = (char *)NULL;
var_is_set = var_is_null = var_is_special = check_nullness = 0;
want_substring = want_indir = want_patsub = 0;
sindex = *indexp;
t_index = ++sindex;
name = string_extract (string, &t_index, "#%:-=?+/}", 1);
/* If the name really consists of a special variable, then make sure
that we have the entire name. We don't allow indirect references
to special variables except `#', `?', `@' and `*'. */
if ((sindex == t_index &&
(string[t_index] == '-' ||
string[t_index] == '?' ||
string[t_index] == '#')) ||
(sindex == t_index - 1 && string[sindex] == '!' &&
(string[t_index] == '#' ||
string[t_index] == '?' ||
string[t_index] == '@' ||
string[t_index] == '*')))
{
t_index++;
free (name);
temp1 = string_extract (string, &t_index, "#%:-=?+/}", 0);
name = xmalloc (3 + (strlen (temp1)));
*name = string[sindex];
if (string[sindex] == '!')
{
/* indirect reference of $#, $?, $@, or $* */
name[1] = string[sindex + 1];
strcpy (name + 2, temp1);
}
else
strcpy (name + 1, temp1);
free (temp1);
}
sindex = t_index;
/* Find out what character ended the variable name. Then
do the appropriate thing. */
if (c = string[sindex])
sindex++;
/* If c is followed by one of the valid parameter expansion
characters, move past it as normal. If not, assume that
a substring specification is being given, and do not move
past it. */
if (c == ':' && member (string[sindex], "-=?+"))
{
check_nullness++;
if (c = string[sindex])
sindex++;
}
else if (c == ':' && string[sindex] != RBRACE)
want_substring = 1;
else if (c == '/' && string[sindex] != RBRACE)
want_patsub = 1;
/* Catch the valid and invalid brace expressions that made it through the
tests above. */
/* ${#-} is a valid expansion and means to take the length of $-.
Similarly for ${#?} and ${##}... */
if (name[0] == '#' && name[1] == '\0' && check_nullness == 0 &&
member (c, "-?#") && string[sindex] == RBRACE)
{
name = xrealloc (name, 3);
name[1] = c;
name[2] = '\0';
c = string[sindex++];
}
/* ...but ${#%}, ${#:}, ${#=}, ${#+}, and ${#/} are errors. */
if (name[0] == '#' && name[1] == '\0' && check_nullness == 0 &&
member (c, "%:=+/") && string[sindex] == RBRACE)
{
temp = (char *)NULL;
goto bad_substitution;
}
/* Indirect expansion begins with a `!'. A valid indirect expansion is
either a variable name, one of the positional parameters or a special
variable that expands to one of the positional parameters. */
want_indir = *name == '!' &&
(legal_variable_starter (name[1]) || digit (name[1]) || member (name[1], "#?@*"));
/* Determine the value of this variable. */
/* Check for special variables, directly referenced. */
if (SPECIAL_VAR (name, want_indir))
var_is_special++;
/* Check for special expansion things, like the length of a parameter */
if (*name == '#' && name[1])
{
/* If we are not pointing at the character just after the
closing brace, then we haven't gotten all of the name.
Since it begins with a special character, this is a bad
substitution. Also check NAME for validity before trying
to go on. */
if (string[sindex - 1] != RBRACE || (valid_length_expression (name) == 0))
{
temp = (char *)NULL;
goto bad_substitution;
}
number = parameter_brace_expand_length (name);
free (name);
*indexp = sindex;
return ((number < 0) ? &expand_param_error : itos (number));
}
/* ${@} is identical to $@. */
if (name[0] == '@' && name[1] == '\0')
{
if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) && quoted_dollar_atp)
*quoted_dollar_atp = 1;
if (contains_dollar_at)
*contains_dollar_at = 1;
}
/* Process ${PREFIX*} expansion. */
if (want_indir && string[sindex - 1] == RBRACE &&
(string[sindex - 2] == '*' || string[sindex - 2] == '@') &&
legal_variable_starter (name[1]))
{
char **x;
WORD_LIST *xlist;
temp1 = savestring (name + 1);
number = strlen (temp1);
temp1[number - 1] = '\0';
x = all_variables_matching_prefix (temp1);
xlist = argv_to_word_list (x, 1, 0);
temp = string_list_dollar_star (xlist, quoted);
free (x);
free (xlist);
free (temp1);
*indexp = sindex;
return (temp);
}
/* Make sure that NAME is valid before trying to go on. */
if (valid_brace_expansion_word (want_indir ? name + 1 : name,
var_is_special) == 0)
{
temp = (char *)NULL;
goto bad_substitution;
}
if (want_indir)
temp = parameter_brace_expand_indir (name + 1, var_is_special, quoted);
else
temp = parameter_brace_expand_word (name, var_is_special, quoted);
#if defined (ARRAY_VARS)
#if 0
if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) && valid_array_reference (name))
#else
if (valid_array_reference (name))
#endif
{
temp1 = strchr (name, '[');
if (temp1 && temp1[1] == '@' && temp1[2] == ']')
{
if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) && quoted_dollar_atp)
*quoted_dollar_atp = 1;
if (contains_dollar_at)
*contains_dollar_at = 1;
} /* [ */
/* ${array[*]}, when unquoted, should be treated like ${array[@]},
which should result in separate words even when IFS is unset. */
if (temp1 && temp1[1] == '*' && temp1[2] == ']' && quoted == 0)
{
if (contains_dollar_at)
*contains_dollar_at = 1;
}
}
#endif
var_is_set = temp != (char *)0;
var_is_null = check_nullness && (var_is_set == 0 || *temp == 0);
/* Get the rest of the stuff inside the braces. */
if (c && c != RBRACE)
{
/* Extract the contents of the ${ ... } expansion
according to the Posix.2 rules. */
value = extract_dollar_brace_string (string, &sindex, quoted);
if (string[sindex] == RBRACE)
sindex++;
else
goto bad_substitution;
}
else
value = (char *)NULL;
*indexp = sindex;
/* If this is a substring spec, process it and add the result. */
if (want_substring)
{
temp1 = parameter_brace_substring (name, temp, value, quoted);
FREE (name);
FREE (value);
FREE (temp);
return (temp1);
}
else if (want_patsub)
{
temp1 = parameter_brace_patsub (name, temp, value, quoted);
FREE (name);
FREE (value);
FREE (temp);
return (temp1);
}
/* Do the right thing based on which character ended the variable name. */
switch (c)
{
default:
case '\0':
bad_substitution:
report_error ("%s: bad substitution", string ? string : "??");
FREE (value);
FREE (temp);
free (name);
return &expand_param_error;
case RBRACE:
if (var_is_set == 0 && unbound_vars_is_error)
{
report_error ("%s: unbound variable", name);
FREE (value);
FREE (temp);
free (name);
last_command_exit_value = EXECUTION_FAILURE;
return (interactive_shell ? &expand_param_error : &expand_param_fatal);
}
break;
case '#': /* ${param#[#]pattern} */
case '%': /* ${param%[%]pattern} */
if (value == 0 || *value == '\0' || temp == 0 || *temp == '\0')
{
FREE (value);
break;
}
if ((name[0] == '@' || name[0] == '*') && name[1] == '\0')
temp1 = parameter_list_remove_pattern (value, name[0], c, quoted);
#if defined (ARRAY_VARS)
else if (valid_array_reference (name))
temp1 = array_remove_pattern (value, name, temp, c, quoted);
#endif
else
temp1 = parameter_brace_remove_pattern (value, temp, c, quoted);
free (temp);
free (value);
temp = temp1;
break;
case '-':
case '=':
case '?':
case '+':
if (var_is_set && var_is_null == 0)
{
/* We don't want the value of the named variable for
anything, just the value of the right hand side. */
/* XXX -- if we're double-quoted and the named variable is "$@",
we want to turn off any special handling of "$@" -- we're not
using it, so whatever is on the rhs applies. */
if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) && quoted_dollar_atp)
*quoted_dollar_atp = 0;
if (contains_dollar_at)
*contains_dollar_at = 0;
if (c == '+')
{
FREE (temp);
if (value)
{
temp = parameter_brace_expand_rhs (name, value, c,
quoted,
quoted_dollar_atp,
contains_dollar_at);
free (value);
}
else
temp = (char *)NULL;
}
else
{
FREE (value);
}
/* Otherwise do nothing; just use the value in TEMP. */
}
else /* VAR not set or VAR is NULL. */
{
FREE (temp);
temp = (char *)NULL;
if (c == '=' && var_is_special)
{
report_error ("$%s: cannot assign in this way", name);
free (name);
free (value);
return &expand_param_error;
}
else if (c == '?')
{
parameter_brace_expand_error (name, value);
return (interactive ? &expand_param_error : &expand_param_fatal);
}
else if (c != '+')
temp = parameter_brace_expand_rhs (name, value, c, quoted,
quoted_dollar_atp,
contains_dollar_at);
free (value);
}
break;
}
free (name);
return (temp);
}
/* Expand a single ${xxx} expansion. The braces are optional. When
the braces are used, parameter_brace_expand() does the work,
possibly calling param_expand recursively. */
static char *
param_expand (string, sindex, quoted, expanded_something,
contains_dollar_at, quoted_dollar_at_p, had_quoted_null_p,
pflags)
char *string;
int *sindex, quoted, *expanded_something, *contains_dollar_at;
int *quoted_dollar_at_p, *had_quoted_null_p, pflags;
{
char *temp, *temp1;
int zindex, number, c, t_index, expok;
SHELL_VAR *var;
WORD_LIST *list, *tlist;
zindex = *sindex;
c = string[++zindex];
temp = (char *)NULL;
/* Do simple cases first. Switch on what follows '$'. */
switch (c)
{
/* $0 .. $9? */
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
temp1 = dollar_vars[digit_value (c)];
if (unbound_vars_is_error && temp1 == (char *)NULL)
{
report_error ("$%c: unbound variable", c);
last_command_exit_value = EXECUTION_FAILURE;
return (interactive_shell ? &expand_param_error : &expand_param_fatal);
}
temp = temp1 ? savestring (temp1) : (char *)NULL;
break;
/* $$ -- pid of the invoking shell. */
case '$':
temp = itos (dollar_dollar_pid);
break;
/* $# -- number of positional parameters. */
case '#':
temp = itos (number_of_args ());
break;
/* $? -- return value of the last synchronous command. */
case '?':
temp = itos (last_command_exit_value);
break;
/* $- -- flags supplied to the shell on invocation or by `set'. */
case '-':
temp = which_set_flags ();
break;
/* $! -- Pid of the last asynchronous command. */
case '!':
/* If no asynchronous pids have been created, expand to nothing.
If `set -u' has been executed, and no async processes have
been created, this is an expansion error. */
if (last_asynchronous_pid == NO_PID)
{
if (expanded_something)
*expanded_something = 0;
temp = (char *)NULL;
if (unbound_vars_is_error)
{
report_error ("$%c: unbound variable", c);
last_command_exit_value = EXECUTION_FAILURE;
return (interactive_shell ? &expand_param_error : &expand_param_fatal);
}
}
else
temp = itos ((int)last_asynchronous_pid);
break;
/* The only difference between this and $@ is when the arg is quoted. */
case '*': /* `$*' */
list = list_rest_of_args ();
/* If there are no command-line arguments, this should just
disappear if there are other characters in the expansion,
even if it's quoted. */
if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) && list == 0)
temp = (char *)NULL;
else if (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES))
{
/* If we have "$*" we want to make a string of the positional
parameters, separated by the first character of $IFS, and
quote the whole string, including the separators. If IFS
is unset, the parameters are separated by ' '; if $IFS is
null, the parameters are concatenated. */
temp = string_list_dollar_star (list);
temp1 = quote_string (temp);
free (temp);
temp = temp1;
}
else
{
/* If the $* is not quoted it is identical to $@ */
temp = string_list_dollar_at (list, quoted);
if (contains_dollar_at)
*contains_dollar_at = 1;
}
dispose_words (list);
break;
/* When we have "$@" what we want is "$1" "$2" "$3" ... This
means that we have to turn quoting off after we split into
the individually quoted arguments so that the final split
on the first character of $IFS is still done. */
case '@': /* `$@' */
list = list_rest_of_args ();
/* We want to flag the fact that we saw this. We can't turn
off quoting entirely, because other characters in the
string might need it (consider "\"$@\""), but we need some
way to signal that the final split on the first character
of $IFS should be done, even though QUOTED is 1. */
if (quoted_dollar_at_p && (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)))
*quoted_dollar_at_p = 1;
if (contains_dollar_at)
*contains_dollar_at = 1;
/* We want to separate the positional parameters with the first
character of $IFS in case $IFS is something other than a space.
We also want to make sure that splitting is done no matter what --
according to POSIX.2, this expands to a list of the positional
parameters no matter what IFS is set to. */
temp = string_list_dollar_at (list, quoted);
dispose_words (list);
break;
case LBRACE:
temp = parameter_brace_expand (string, &zindex, quoted,
quoted_dollar_at_p,
contains_dollar_at);
if (temp == &expand_param_error || temp == &expand_param_fatal)
return (temp);
/* XXX */
/* Quoted nulls should be removed if there is anything else
in the string. */
/* Note that we saw the quoted null so we can add one back at
the end of this function if there are no other characters
in the string, discard TEMP, and go on. */
if (temp && QUOTED_NULL (temp))
{
if (had_quoted_null_p)
*had_quoted_null_p = 1;
free (temp);
temp = (char *)NULL;
}
goto return0;
/* Do command or arithmetic substitution. */
case LPAREN:
/* We have to extract the contents of this paren substitution. */
t_index = zindex + 1;
temp = extract_command_subst (string, &t_index);
zindex = t_index;
/* For Posix.2-style `$(( ))' arithmetic substitution,
extract the expression and pass it to the evaluator. */
if (temp && *temp == LPAREN)
{
char *temp2;
temp1 = temp + 1;
temp2 = savestring (temp1);
t_index = strlen (temp2) - 1;
if (temp2[t_index] != RPAREN)
{
free (temp2);
goto comsub;
}
/* Cut off ending `)' */
temp2[t_index] = '\0';
/* Expand variables found inside the expression. */
temp1 = maybe_expand_string (temp2, Q_DOUBLE_QUOTES, expand_string);
free (temp2);
arithsub:
/* No error messages. */
this_command_name = (char *)NULL;
number = evalexp (temp1, &expok);
free (temp);
free (temp1);
if (expok == 0)
{
if (interactive_shell == 0 && posixly_correct)
{
last_command_exit_value = EXECUTION_FAILURE;
return (&expand_param_fatal);
}
else
return (&expand_param_error);
}
temp = itos (number);
break;
}
comsub:
temp1 = command_substitute (temp, quoted);
FREE (temp);
temp = temp1;
break;
/* Do POSIX.2d9-style arithmetic substitution. This will probably go
away in a future bash release. */
case '[':
/* Extract the contents of this arithmetic substitution. */
t_index = zindex + 1;
temp = extract_arithmetic_subst (string, &t_index);
zindex = t_index;
/* Do initial variable expansion. */
temp1 = maybe_expand_string (temp, Q_DOUBLE_QUOTES, expand_string);
goto arithsub;
default:
/* Find the variable in VARIABLE_LIST. */
temp = (char *)NULL;
for (t_index = zindex; (c = string[zindex]) && legal_variable_char (c); zindex++)
;
temp1 = (zindex > t_index) ? substring (string, t_index, zindex) : (char *)NULL;
/* If this isn't a variable name, then just output the `$'. */
if (temp1 == 0 || *temp1 == '\0')
{
FREE (temp1);
temp = xmalloc (2);
temp[0] = '$';
temp[1] = '\0';
if (expanded_something)
*expanded_something = 0;
goto return0;
}
/* If the variable exists, return its value cell. */
var = find_variable (temp1);
if (var && invisible_p (var) == 0 && value_cell (var))
{
#if defined (ARRAY_VARS)
if (array_p (var))
{
temp = array_reference (array_cell (var), 0);
if (temp)
temp = quote_escapes (temp);
}
else
#endif
temp = quote_escapes (value_cell (var));
free (temp1);
if (tempvar_p (var)) /* XXX */
{
dispose_variable (var); /* XXX */
var = (SHELL_VAR *)NULL;
}
goto return0;
}
temp = (char *)NULL;
if (unbound_vars_is_error)
report_error ("%s: unbound variable", temp1);
else
{
free (temp1);
goto return0;
}
free (temp1);
last_command_exit_value = EXECUTION_FAILURE;
return ((unbound_vars_is_error && interactive_shell == 0)
? &expand_param_fatal
: &expand_param_error);
}
if (string[zindex])
zindex++;
return0:
*sindex = zindex;
return (temp);
}
/* Make a word list which is the result of parameter and variable
expansion, command substitution, arithmetic substitution, and
quote removal of WORD. Return a pointer to a WORD_LIST which is
the result of the expansion. If WORD contains a null word, the
word list returned is also null.
QUOTED contains flag values defined in shell.h.
ISEXP is used to tell expand_word_internal that the word should be
treated as the result of an expansion. This has implications for
how IFS characters in the word are treated.
CONTAINS_DOLLAR_AT and EXPANDED_SOMETHING are return values; when non-null
they point to an integer value which receives information about expansion.
CONTAINS_DOLLAR_AT gets non-zero if WORD contained "$@", else zero.
EXPANDED_SOMETHING get non-zero if WORD contained any parameter expansions,
else zero.
This only does word splitting in the case of $@ expansion. In that
case, we split on ' '. */
/* Values for the local variable quoted_state. */
#define UNQUOTED 0
#define PARTIALLY_QUOTED 1
#define WHOLLY_QUOTED 2
static WORD_LIST *
expand_word_internal (word, quoted, isexp, contains_dollar_at, expanded_something)
WORD_DESC *word;
int quoted, isexp;
int *contains_dollar_at;
int *expanded_something;
{
WORD_LIST *list;
WORD_DESC *tword;
SHELL_VAR *var;
/* The intermediate string that we build while expanding. */
char *istring;
/* The current size of the above object. */
int istring_size;
/* Index into ISTRING. */
int istring_index;
/* Temporary string storage. */
char *temp, *temp1;
/* The text of WORD. */
register char *string;
/* The index into STRING. */
int sindex;
/* This gets 1 if we see a $@ while quoted. */
int quoted_dollar_at;
/* One of UNQUOTED, PARTIALLY_QUOTED, or WHOLLY_QUOTED, depending on
whether WORD contains no quoting characters, a partially quoted
string (e.g., "xx"ab), or is fully quoted (e.g., "xxab"). */
int quoted_state;
int had_quoted_null;
int has_dollar_at;
register int c; /* Current character. */
int number; /* Temporary number value. */
int t_index; /* For calls to string_extract_xxx. */
char ifscmap[256];
char twochars[2];
istring = xmalloc (istring_size = DEFAULT_INITIAL_ARRAY_SIZE);
istring[istring_index = 0] = '\0';
quoted_dollar_at = had_quoted_null = has_dollar_at = 0;
quoted_state = UNQUOTED;
string = word->word;
if (string == 0)
goto finished_with_string;
if (contains_dollar_at)
*contains_dollar_at = 0;
/* Cache a bitmap of characters in IFS for quoting IFS characters that are
not part of an expansion. POSIX.2 says this is a must. */
temp = getifs ();
bzero (ifscmap, sizeof (ifscmap));
for (temp1 = temp; temp1 && *temp1; temp1++)
#if 0
/* This check compensates for what I think is a parsing problem -- the
end brace matching algorithms for ${...} expressions differ between
parse.y and subst.c. For instance, the parser passes
${abc:-G { I } K } as one word when it should be three. */
if (*temp1 != ' ' && *temp1 != '\t' && *temp1 != '\n')
#endif
ifscmap[(unsigned char)*temp1] = 1;
/* Begin the expansion. */
for (sindex = 0; ;)
{
c = string[sindex];
/* Case on toplevel character. */
switch (c)
{
case '\0':
goto finished_with_string;
case CTLESC:
temp = xmalloc (3);
temp[0] = CTLESC;
temp[1] = c = string[++sindex];
temp[2] = '\0';
dollar_add_string:
if (string[sindex])
sindex++;
add_string:
if (temp)
{
istring = sub_append_string (temp, istring, &istring_index, &istring_size);
temp = (char *)0;
}
break;
#if defined (PROCESS_SUBSTITUTION)
/* Process substitution. */
case '<':
case '>':
{
if (string[++sindex] != LPAREN || (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) || posixly_correct)
{
sindex--; /* add_character: label increments sindex */
goto add_character;
}
else
t_index = sindex + 1; /* skip past both '<' and LPAREN */
temp1 = extract_process_subst (string, (c == '<') ? "<(" : ">(", &t_index); /*))*/
sindex = t_index;
/* If the process substitution specification is `<()', we want to
open the pipe for writing in the child and produce output; if
it is `>()', we want to open the pipe for reading in the child
and consume input. */
temp = temp1 ? process_substitute (temp1, (c == '>')) : (char *)0;
FREE (temp1);
goto dollar_add_string;
}
#endif /* PROCESS_SUBSTITUTION */
case '$':
if (expanded_something)
*expanded_something = 1;
has_dollar_at = 0;
temp = param_expand (string, &sindex, quoted, expanded_something,
&has_dollar_at, &quoted_dollar_at,
&had_quoted_null, 0);
if (temp == &expand_param_error || temp == &expand_param_fatal)
{
free (string);
free (istring);
return ((temp == &expand_param_error) ? &expand_word_error
: &expand_word_fatal);
}
if (contains_dollar_at && has_dollar_at)
*contains_dollar_at = 1;
goto add_string;
break;
case '`': /* Backquoted command substitution. */
{
sindex++;
if (expanded_something)
*expanded_something = 1;
temp = string_extract (string, &sindex, "`", 0);
de_backslash (temp);
temp1 = command_substitute (temp, quoted);
FREE (temp);
temp = temp1;
goto dollar_add_string;
}
case '\\':
if (string[sindex + 1] == '\n')
{
sindex += 2;
continue;
}
c = string[++sindex];
if (quoted & Q_HERE_DOCUMENT)
temp1 = slashify_in_here_document;
else if (quoted & Q_DOUBLE_QUOTES)
temp1 = slashify_in_quotes;
else
temp1 = "";
if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) && member (c, temp1) == 0)
{
twochars[0] = '\\';
twochars[1] = c;
}
else if (c == 0)
{
c = CTLNUL;
sindex--; /* add_character: label increments sindex */
goto add_character;
}
else
{
twochars[0] = CTLESC;
twochars[1] = c;
}
sindex++;
add_twochars:
/* BEFORE jumping here, we need to increment sindex if appropriate */
RESIZE_MALLOCED_BUFFER (istring, istring_index, 2, istring_size,
DEFAULT_ARRAY_SIZE);
istring[istring_index++] = twochars[0];
istring[istring_index++] = twochars[1];
istring[istring_index] = '\0';
break;
case '"':
if (quoted & (Q_DOUBLE_QUOTES|Q_HERE_DOCUMENT|Q_NOQUOTE))
goto add_character;
t_index = ++sindex;
temp = string_extract_double_quoted (string, &sindex, 0);
/* If the quotes surrounded the entire string, then the
whole word was quoted. */
quoted_state = (t_index == 1 && string[sindex] == '\0')
? WHOLLY_QUOTED
: PARTIALLY_QUOTED;
if (temp && *temp)
{
tword = make_word (temp); /* XXX */
free (temp);
temp = (char *)NULL;
has_dollar_at = 0;
list = expand_word_internal (tword, Q_DOUBLE_QUOTES, 0, &has_dollar_at, (int *)NULL);
if (list == &expand_word_error || list == &expand_word_fatal)
{
free (istring);
free (string);
/* expand_word_internal has already freed temp_word->word
for us because of the way it prints error messages. */
tword->word = (char *)NULL;
dispose_word (tword);
return list;
}
dispose_word (tword);
/* "$@" (a double-quoted dollar-at) expands into nothing,
not even a NULL word, when there are no positional
parameters. */
if (list == 0 && has_dollar_at)
{
quoted_dollar_at++;
break;
}
/* If we get "$@", we know we have expanded something, so we
need to remember it for the final split on $IFS. This is
a special case; it's the only case where a quoted string
can expand into more than one word. It's going to come back
from the above call to expand_word_internal as a list with
a single word, in which all characters are quoted and
separated by blanks. What we want to do is to turn it back
into a list for the next piece of code. */
if (list)
dequote_list (list);
if (has_dollar_at)
{
quoted_dollar_at++;
if (contains_dollar_at)
*contains_dollar_at = 1;
if (expanded_something)
*expanded_something = 1;
}
}
else
{
/* What we have is "". This is a minor optimization. */
free (temp);
list = (WORD_LIST *)NULL;
}
/* The code above *might* return a list (consider the case of "$@",
where it returns "$1", "$2", etc.). We can't throw away the
rest of the list, and we have to make sure each word gets added
as quoted. We test on tresult->next: if it is non-NULL, we
quote the whole list, save it to a string with string_list, and
add that string. We don't need to quote the results of this
(and it would be wrong, since that would quote the separators
as well), so we go directly to add_string. */
if (list)
{
if (list->next)
{
/* Testing quoted_dollar_at makes sure that "$@" is
split correctly when $IFS does not contain a space. */
temp = quoted_dollar_at
? string_list_dollar_at (list, Q_DOUBLE_QUOTES)
: string_list (quote_list (list));
dispose_words (list);
goto add_string;
}
else
{
temp = savestring (list->word->word);
dispose_words (list);
#if 1
/* If the string is not a quoted null string, we want
to remove any embedded unquoted CTLNUL characters.
We do not want to turn quoted null strings back into
the empty string, though. We do this because we
want to remove any quoted nulls from expansions that
contain other characters. For example, if we have
x"$*"y or "x$*y" and there are no positional parameters,
the $* should expand into nothing. */
if (QUOTED_NULL (temp) == 0)
remove_quoted_nulls (temp); /* XXX */
#endif
}
}
else
temp = (char *)NULL;
/* We do not want to add quoted nulls to strings that are only
partially quoted; we can throw them away. */
if (temp == 0 && quoted_state == PARTIALLY_QUOTED)
continue;
add_quoted_string:
if (temp)
{
temp1 = temp;
temp = quote_string (temp);
free (temp1);
goto add_string;
}
else
{
/* Add NULL arg. */
c = CTLNUL;
sindex--; /* add_character: label increments sindex */
goto add_character;
}
/* break; */
case '\'':
if (quoted & (Q_DOUBLE_QUOTES|Q_HERE_DOCUMENT|Q_NOQUOTE))
goto add_character;
t_index = ++sindex;
temp = string_extract_single_quoted (string, &sindex);
/* If the entire STRING was surrounded by single quotes,
then the string is wholly quoted. */
quoted_state = (t_index == 1 && string[sindex] == '\0')
? WHOLLY_QUOTED
: PARTIALLY_QUOTED;
/* If all we had was '', it is a null expansion. */
if (*temp == '\0')
{
free (temp);
temp = (char *)NULL;
}
else
remove_quoted_escapes (temp);
/* We do not want to add quoted nulls to strings that are only
partially quoted; such nulls are discarded. */
if (temp == 0 && (quoted_state == PARTIALLY_QUOTED))
continue;
/* If we have a quoted null expansion, add a quoted NULL to istring. */
if (temp == 0)
{
c = CTLNUL;
sindex--; /* add_character: label increments sindex */
goto add_character;
}
else
goto add_quoted_string;
/* break; */
default:
/* This is the fix for " $@ " */
if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) || (isexp == 0 && ifscmap[c]))
{
if (string[sindex]) /* from old goto dollar_add_string */
sindex++;
if (c == 0)
{
c = CTLNUL;
goto add_character;
}
else
{
twochars[0] = CTLESC;
twochars[1] = c;
goto add_twochars;
}
}
add_character:
RESIZE_MALLOCED_BUFFER (istring, istring_index, 1, istring_size,
DEFAULT_ARRAY_SIZE);
istring[istring_index++] = c;
istring[istring_index] = '\0';
/* Next character. */
sindex++;
}
}
finished_with_string:
/* OK, we're ready to return. If we have a quoted string, and
quoted_dollar_at is not set, we do no splitting at all; otherwise
we split on ' '. The routines that call this will handle what to
do if nothing has been expanded. */
/* Partially and wholly quoted strings which expand to the empty
string are retained as an empty arguments. Unquoted strings
which expand to the empty string are discarded. The single
exception is the case of expanding "$@" when there are no
positional parameters. In that case, we discard the expansion. */
/* Because of how the code that handles "" and '' in partially
quoted strings works, we need to make ISTRING into a QUOTED_NULL
if we saw quoting characters, but the expansion was empty.
"" and '' are tossed away before we get to this point when
processing partially quoted strings. This makes "" and $xxx""
equivalent when xxx is unset. We also look to see whether we
saw a quoted null from a ${} expansion and add one back if we
need to. */
/* If we expand to nothing and there were no single or double quotes
in the word, we throw it away. Otherwise, we return a NULL word.
The single exception is for $@ surrounded by double quotes when
there are no positional parameters. In that case, we also throw
the word away. */
if (*istring == '\0')
{
if (quoted_dollar_at == 0 && (had_quoted_null || quoted_state == PARTIALLY_QUOTED))
{
istring[0] = CTLNUL;
istring[1] = '\0';
tword = make_bare_word (istring);
list = make_word_list (tword, (WORD_LIST *)NULL);
if (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES))
tword->flags |= W_QUOTED;
}
/* According to sh, ksh, and Posix.2, if a word expands into nothing
and a double-quoted "$@" appears anywhere in it, then the entire
word is removed. */
else if (quoted_state == UNQUOTED || quoted_dollar_at)
list = (WORD_LIST *)NULL;
#if 0
else
{
tword = make_bare_word (istring);
list = make_word_list (tword, (WORD_LIST *)NULL);
if (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES))
tword->flags |= W_QUOTED;
}
#endif
}
else if (word->flags & W_NOSPLIT)
{
tword = make_bare_word (istring);
list = make_word_list (tword, (WORD_LIST *)NULL);
if (word->flags & W_ASSIGNMENT)
tword->flags |= W_ASSIGNMENT; /* XXX */
if (word->flags & W_NOGLOB)
tword->flags |= W_NOGLOB; /* XXX */
if (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES))
tword->flags |= W_QUOTED;
}
else
{
char *ifs_chars;
ifs_chars = (quoted_dollar_at || has_dollar_at) ? getifs () : (char *)NULL;
/* If we have $@, we need to split the results no matter what. If
IFS is unset or NULL, string_list_dollar_at has separated the
positional parameters with a space, so we split on space (we have
set ifs_chars to " \t\n" above if ifs is unset). If IFS is set,
string_list_dollar_at has separated the positional parameters
with the first character of $IFS, so we split on $IFS. */
if (has_dollar_at && ifs_chars)
list = list_string (istring, *ifs_chars ? ifs_chars : " ", 1);
else
{
tword = make_bare_word (istring);
list = make_word_list (tword, (WORD_LIST *)NULL);
if ((quoted & (Q_DOUBLE_QUOTES|Q_HERE_DOCUMENT)) || (quoted_state == WHOLLY_QUOTED))
tword->flags |= W_QUOTED;
if (word->flags & W_ASSIGNMENT)
tword->flags |= W_ASSIGNMENT;
if (word->flags & W_NOGLOB)
tword->flags |= W_NOGLOB;
}
}
free (istring);
return (list);
}
/* **************************************************************** */
/* */
/* Functions for Quote Removal */
/* */
/* **************************************************************** */
/* Perform quote removal on STRING. If QUOTED > 0, assume we are obeying the
backslash quoting rules for within double quotes. */
char *
string_quote_removal (string, quoted)
char *string;
int quoted;
{
char *r, *result_string, *temp;
int sindex, tindex, c, dquote;
/* The result can be no longer than the original string. */
r = result_string = xmalloc (strlen (string) + 1);
for (dquote = sindex = 0; c = string[sindex];)
{
switch (c)
{
case '\\':
c = string[++sindex];
if (((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) || dquote) && member (c, slashify_in_quotes) == 0)
*r++ = '\\';
/* FALLTHROUGH */
default:
*r++ = c;
sindex++;
break;
case '\'':
if ((quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)) || dquote)
{
*r++ = c;
sindex++;
break;
}
tindex = sindex + 1;
temp = string_extract_single_quoted (string, &tindex);
if (temp)
{
strcpy (r, temp);
r += strlen (r);
free (temp);
}
sindex = tindex;
break;
case '"':
dquote = 1 - dquote;
sindex++;
break;
}
}
*r = '\0';
return (result_string);
}
#if 0
/* UNUSED */
/* Perform quote removal on word WORD. This allocates and returns a new
WORD_DESC *. */
WORD_DESC *
word_quote_removal (word, quoted)
WORD_DESC *word;
int quoted;
{
WORD_DESC *w;
char *t;
t = string_quote_removal (word->word, quoted);
w = make_bare_word (t);
free (t);
return (w);
}
/* Perform quote removal on all words in LIST. If QUOTED is non-zero,
the members of the list are treated as if they are surrounded by
double quotes. Return a new list, or NULL if LIST is NULL. */
WORD_LIST *
word_list_quote_removal (list, quoted)
WORD_LIST *list;
int quoted;
{
WORD_LIST *result, *t, *tresult;
for (t = list, result = (WORD_LIST *)NULL; t; t = t->next)
{
tresult = (WORD_LIST *)xmalloc (sizeof (WORD_LIST));
tresult->word = word_quote_removal (t->word, quoted);
tresult->next = (WORD_LIST *)NULL;
result = (WORD_LIST *) list_append (result, tresult);
}
return (result);
}
#endif
/*******************************************
* *
* Functions to perform word splitting *
* *
*******************************************/
static char *
getifs ()
{
SHELL_VAR *ifs;
ifs = find_variable ("IFS");
/* If IFS is unset, it defaults to " \t\n". */
return (ifs ? value_cell (ifs) : " \t\n");
}
/* This splits a single word into a WORD LIST on $IFS, but only if the word
is not quoted. list_string () performs quote removal for us, even if we
don't do any splitting. */
WORD_LIST *
word_split (w)
WORD_DESC *w;
{
WORD_LIST *result;
SHELL_VAR *ifs;
char *ifs_chars;
if (w)
{
ifs = find_variable ("IFS");
/* If IFS is unset, it defaults to " \t\n". */
ifs_chars = ifs ? value_cell (ifs) : " \t\n";
if ((w->flags & W_QUOTED) || !ifs_chars)
ifs_chars = "";
result = list_string (w->word, ifs_chars, w->flags & W_QUOTED);
if (ifs && tempvar_p (ifs)) /* XXX */
dispose_variable (ifs); /* XXX */
}
else
result = (WORD_LIST *)NULL;
return (result);
}
/* Perform word splitting on LIST and return the RESULT. It is possible
to return (WORD_LIST *)NULL. */
static WORD_LIST *
word_list_split (list)
WORD_LIST *list;
{
WORD_LIST *result, *t, *tresult;
for (t = list, result = (WORD_LIST *)NULL; t; t = t->next)
{
tresult = word_split (t->word);
result = (WORD_LIST *) list_append (result, tresult);
}
return (result);
}
/**************************************************
* *
* Functions to expand an entire WORD_LIST *
* *
**************************************************/
/* Put NLIST (which is a WORD_LIST * of only one element) at the front of
ELIST, and set ELIST to the new list. */
#define PREPEND_LIST(nlist, elist) \
do { nlist->next = elist; elist = nlist; } while (0)
/* Separate out any initial variable assignments from TLIST. If set -k has
been executed, remove all assignment statements from TLIST. Initial
variable assignments and other environment assignments are placed
on SUBST_ASSIGN_VARLIST. */
static WORD_LIST *
separate_out_assignments (tlist)
WORD_LIST *tlist;
{
register WORD_LIST *vp, *lp;
if (!tlist)
return ((WORD_LIST *)NULL);
if (subst_assign_varlist)
dispose_words (subst_assign_varlist); /* Clean up after previous error */
subst_assign_varlist = (WORD_LIST *)NULL;
vp = lp = tlist;
/* Separate out variable assignments at the start of the command.
Loop invariant: vp->next == lp
Loop postcondition:
lp = list of words left after assignment statements skipped
tlist = original list of words
*/
while (lp && (lp->word->flags & W_ASSIGNMENT))
{
vp = lp;
lp = lp->next;
}
/* If lp != tlist, we have some initial assignment statements.
We make SUBST_ASSIGN_VARLIST point to the list of assignment
words and TLIST point to the remaining words. */
if (lp != tlist)
{
subst_assign_varlist = tlist;
/* ASSERT(vp->next == lp); */
vp->next = (WORD_LIST *)NULL; /* terminate variable list */
tlist = lp; /* remainder of word list */
}
/* vp == end of variable list */
/* tlist == remainder of original word list without variable assignments */
if (!tlist)
/* All the words in tlist were assignment statements */
return ((WORD_LIST *)NULL);
/* ASSERT(tlist != NULL); */
/* ASSERT((tlist->word->flags & W_ASSIGNMENT) == 0); */
/* If the -k option is in effect, we need to go through the remaining
words, separate out the assignment words, and place them on
SUBST_ASSIGN_VARLIST. */
if (place_keywords_in_env)
{
WORD_LIST *tp; /* tp == running pointer into tlist */
tp = tlist;
lp = tlist->next;
/* Loop Invariant: tp->next == lp */
/* Loop postcondition: tlist == word list without assignment statements */
while (lp)
{
if (lp->word->flags & W_ASSIGNMENT)
{
/* Found an assignment statement, add this word to end of
subst_assign_varlist (vp). */
if (!subst_assign_varlist)
subst_assign_varlist = vp = lp;
else
{
vp->next = lp;
vp = lp;
}
/* Remove the word pointed to by LP from TLIST. */
tp->next = lp->next;
/* ASSERT(vp == lp); */
lp->next = (WORD_LIST *)NULL;
lp = tp->next;
}
else
{
tp = lp;
lp = lp->next;
}
}
}
return (tlist);
}
#define WEXP_VARASSIGN 0x001
#define WEXP_BRACEEXP 0x002
#define WEXP_TILDEEXP 0x004
#define WEXP_PARAMEXP 0x008
#define WEXP_PATHEXP 0x010
/* All of the expansions, including variable assignments at the start of
the list. */
#define WEXP_ALL (WEXP_VARASSIGN|WEXP_BRACEEXP|WEXP_TILDEEXP|WEXP_PARAMEXP|WEXP_PATHEXP)
/* All of the expansions except variable assignments at the start of
the list. */
#define WEXP_NOVARS (WEXP_BRACEEXP|WEXP_TILDEEXP|WEXP_PARAMEXP|WEXP_PATHEXP)
/* All of the `shell expansions': brace expansion, tilde expansion, parameter
expansion, command substitution, arithmetic expansion, word splitting, and
quote removal. */
#define WEXP_SHELLEXP (WEXP_BRACEEXP|WEXP_TILDEEXP|WEXP_PARAMEXP)
/* Take the list of words in LIST and do the various substitutions. Return
a new list of words which is the expanded list, and without things like
variable assignments. */
WORD_LIST *
expand_words (list)
WORD_LIST *list;
{
return (expand_word_list_internal (list, WEXP_ALL));
}
/* Same as expand_words (), but doesn't hack variable or environment
variables. */
WORD_LIST *
expand_words_no_vars (list)
WORD_LIST *list;
{
return (expand_word_list_internal (list, WEXP_NOVARS));
}
WORD_LIST *
expand_words_shellexp (list)
WORD_LIST *list;
{
return (expand_word_list_internal (list, WEXP_SHELLEXP));
}
static WORD_LIST *
glob_expand_word_list (tlist, eflags)
WORD_LIST *tlist;
int eflags;
{
char **glob_array, *temp_string;
register int glob_index;
WORD_LIST *glob_list, *output_list, *disposables, *next;
WORD_DESC *tword;
output_list = disposables = (WORD_LIST *)NULL;
glob_array = (char **)NULL;
while (tlist)
{
/* For each word, either globbing is attempted or the word is
added to orig_list. If globbing succeeds, the results are
added to orig_list and the word (tlist) is added to the list
of disposable words. If globbing fails and failed glob
expansions are left unchanged (the shell default), the
original word is added to orig_list. If globbing fails and
failed glob expansions are removed, the original word is
added to the list of disposable words. orig_list ends up
in reverse order and requires a call to reverse_list to
be set right. After all words are examined, the disposable
words are freed. */
next = tlist->next;
/* If the word isn't an assignment and contains an unquoted
pattern matching character, then glob it. */
#if 0
if ((tlist->word->flags & W_ASSIGNMENT) == 0 &&
#else
if ((tlist->word->flags & W_NOGLOB) == 0 &&
#endif
unquoted_glob_pattern_p (tlist->word->word))
{
glob_array = shell_glob_filename (tlist->word->word);
/* Handle error cases.
I don't think we should report errors like "No such file
or directory". However, I would like to report errors
like "Read failed". */
if (GLOB_FAILED (glob_array))
{
glob_array = (char **)xmalloc (sizeof (char *));
glob_array[0] = (char *)NULL;
}
/* Dequote the current word in case we have to use it. */
if (glob_array[0] == NULL)
{
temp_string = dequote_string (tlist->word->word);
free (tlist->word->word);
tlist->word->word = temp_string;
}
/* Make the array into a word list. */
glob_list = (WORD_LIST *)NULL;
for (glob_index = 0; glob_array[glob_index]; glob_index++)
{
tword = make_bare_word (glob_array[glob_index]);
tword->flags |= W_GLOBEXP; /* XXX */
glob_list = make_word_list (tword, glob_list);
}
if (glob_list)
{
output_list = (WORD_LIST *)list_append (glob_list, output_list);
PREPEND_LIST (tlist, disposables);
}
else if (allow_null_glob_expansion == 0)
{
/* Failed glob expressions are left unchanged. */
PREPEND_LIST (tlist, output_list);
}
else
{
/* Failed glob expressions are removed. */
PREPEND_LIST (tlist, disposables);
}
}
else
{
/* Dequote the string. */
temp_string = dequote_string (tlist->word->word);
free (tlist->word->word);
tlist->word->word = temp_string;
PREPEND_LIST (tlist, output_list);
}
free_array (glob_array);
glob_array = (char **)NULL;
tlist = next;
}
if (disposables)
dispose_words (disposables);
if (output_list)
output_list = REVERSE_LIST (output_list, WORD_LIST *);
return (output_list);
}
#if defined (BRACE_EXPANSION)
static WORD_LIST *
brace_expand_word_list (tlist, eflags)
WORD_LIST *tlist;
int eflags;
{
register char **expansions;
char *temp_string;
WORD_LIST *disposables, *output_list, *next;
WORD_DESC *w;
int eindex;
for (disposables = output_list = (WORD_LIST *)NULL; tlist; tlist = next)
{
next = tlist->next;
/* Only do brace expansion if the word has a brace character. If
not, just add the word list element to BRACES and continue. In
the common case, at least when running shell scripts, this will
degenerate to a bunch of calls to `strchr', and then what is
basically a reversal of TLIST into BRACES, which is corrected
by a call to reverse_list () on BRACES when the end of TLIST
is reached. */
if (strchr (tlist->word->word, LBRACE))
{
expansions = brace_expand (tlist->word->word);
for (eindex = 0; temp_string = expansions[eindex]; eindex++)
{
w = make_word (temp_string);
/* If brace expansion didn't change the word, preserve
the flags. We may want to preserve the flags
unconditionally someday -- XXX */
if (STREQ (temp_string, tlist->word->word))
w->flags = tlist->word->flags;
output_list = make_word_list (w, output_list);
free (expansions[eindex]);
}
free (expansions);
/* Add TLIST to the list of words to be freed after brace
expansion has been performed. */
PREPEND_LIST (tlist, disposables);
}
else
PREPEND_LIST (tlist, output_list);
}
if (disposables)
dispose_words (disposables);
if (output_list)
output_list = REVERSE_LIST (output_list, WORD_LIST *);
return (output_list);
}
#endif
static WORD_LIST *
shell_expand_word_list (tlist, eflags)
WORD_LIST *tlist;
int eflags;
{
WORD_LIST *expanded, *orig_list, *new_list, *next, *temp_list;
int expanded_something, has_dollar_at;
char *temp_string;
/* We do tilde expansion all the time. This is what 1003.2 says. */
new_list = (WORD_LIST *)NULL;
for (orig_list = tlist; tlist; tlist = next)
{
temp_string = tlist->word->word;
next = tlist->next;
/* Posix.2 section 3.6.1 says that tildes following `=' in words
which are not assignment statements are not expanded. We do
this only if POSIXLY_CORRECT is enabled. Essentially, we do
tilde expansion on unquoted assignment statements (flags include
W_ASSIGNMENT but not W_QUOTED). */
if (temp_string[0] == '~' ||
(((tlist->word->flags & (W_ASSIGNMENT|W_QUOTED)) == W_ASSIGNMENT) &&
posixly_correct == 0 &&
strchr (temp_string, '~') &&
(unquoted_substring ("=~", temp_string) || unquoted_substring (":~", temp_string))))
{
tlist->word->word = bash_tilde_expand (temp_string);
free (temp_string);
}
expanded_something = 0;
expanded = expand_word_internal
(tlist->word, 0, 0, &has_dollar_at, &expanded_something);
if (expanded == &expand_word_error || expanded == &expand_word_fatal)
{
/* By convention, each time this error is returned,
tlist->word->word has already been freed. */
tlist->word->word = (char *)NULL;
/* Dispose our copy of the original list. */
dispose_words (orig_list);
/* Dispose the new list we're building. */
dispose_words (new_list);
if (expanded == &expand_word_error)
jump_to_top_level (DISCARD);
else
jump_to_top_level (FORCE_EOF);
}
/* Don't split words marked W_NOSPLIT. */
if (expanded_something && (tlist->word->flags & W_NOSPLIT) == 0)
{
temp_list = word_list_split (expanded);
dispose_words (expanded);
}
else
{
/* If no parameter expansion, command substitution, process
substitution, or arithmetic substitution took place, then
do not do word splitting. We still have to remove quoted
null characters from the result. */
word_list_remove_quoted_nulls (expanded);
temp_list = expanded;
}
expanded = REVERSE_LIST (temp_list, WORD_LIST *);
new_list = (WORD_LIST *)list_append (expanded, new_list);
}
if (orig_list)
dispose_words (orig_list);
if (new_list)
new_list = REVERSE_LIST (new_list, WORD_LIST *);
return (new_list);
}
/* The workhorse for expand_words () and expand_words_no_vars ().
First arg is LIST, a WORD_LIST of words.
Second arg EFLAGS is a flags word controlling which expansions are
performed.
This does all of the substitutions: brace expansion, tilde expansion,
parameter expansion, command substitution, arithmetic expansion,
process substitution, word splitting, and pathname expansion, according
to the bits set in EFLAGS. Words with the W_QUOTED or W_NOSPLIT bits
set, or for which no expansion is done, do not undergo word splitting.
Words with the W_NOGLOB bit set do not undergo pathname expansion. */
static WORD_LIST *
expand_word_list_internal (list, eflags)
WORD_LIST *list;
int eflags;
{
WORD_LIST *new_list, *temp_list;
int tint;
if (list == 0)
return ((WORD_LIST *)NULL);
garglist = new_list = copy_word_list (list);
if (eflags & WEXP_VARASSIGN)
{
garglist = new_list = separate_out_assignments (new_list);
if (new_list == 0)
{
if (subst_assign_varlist)
{
/* All the words were variable assignments, so they are placed
into the shell's environment. */
for (temp_list = subst_assign_varlist; temp_list; temp_list = temp_list->next)
{
this_command_name = (char *)NULL; /* no arithmetic errors */
tint = do_assignment (temp_list->word->word);
/* Variable assignment errors in non-interactive shells
running in Posix.2 mode cause the shell to exit. */
if (tint == 0 && interactive_shell == 0 && posixly_correct)
{
last_command_exit_value = EXECUTION_FAILURE;
jump_to_top_level (FORCE_EOF);
}
}
dispose_words (subst_assign_varlist);
subst_assign_varlist = (WORD_LIST *)NULL;
}
return ((WORD_LIST *)NULL);
}
}
/* Begin expanding the words that remain. The expansions take place on
things that aren't really variable assignments. */
#if defined (BRACE_EXPANSION)
/* Do brace expansion on this word if there are any brace characters
in the string. */
if ((eflags & WEXP_BRACEEXP) && brace_expansion && new_list)
new_list = brace_expand_word_list (new_list, eflags);
#endif /* BRACE_EXPANSION */
/* Perform the `normal' shell expansions: tilde expansion, parameter and
variable substitution, command substitution, arithmetic expansion,
and word splitting. */
new_list = shell_expand_word_list (new_list, eflags);
/* Okay, we're almost done. Now let's just do some filename
globbing. */
if (new_list)
{
if ((eflags & WEXP_PATHEXP) && disallow_filename_globbing == 0)
/* Glob expand the word list unless globbing has been disabled. */
new_list = glob_expand_word_list (new_list, eflags);
else
/* Dequote the words, because we're not performing globbing. */
new_list = dequote_list (new_list);
}
if ((eflags & WEXP_VARASSIGN) && subst_assign_varlist)
{
Function *assign_func;
/* If the remainder of the words expand to nothing, Posix.2 requires
that the variable and environment assignments affect the shell's
environment. */
assign_func = new_list ? assign_in_env : do_assignment;
for (temp_list = subst_assign_varlist; temp_list; temp_list = temp_list->next)
{
this_command_name = (char *)NULL;
tint = (*assign_func) (temp_list->word->word);
/* Variable assignment errors in non-interactive shells running
in Posix.2 mode cause the shell to exit. */
if (tint == 0 && assign_func == do_assignment &&
interactive_shell == 0 && posixly_correct)
{
last_command_exit_value = EXECUTION_FAILURE;
jump_to_top_level (FORCE_EOF);
}
}
dispose_words (subst_assign_varlist);
subst_assign_varlist = (WORD_LIST *)NULL;
}
#if 0
tint = list_length (new_list) + 1;
RESIZE_MALLOCED_BUFFER (glob_argv_flags, 0, tint, glob_argv_flags_size, 16);
for (tint = 0, temp_list = new_list; temp_list; temp_list = temp_list->next)
glob_argv_flags[tint++] = (temp_list->word->flags & W_GLOBEXP) ? '1' : '0';
glob_argv_flags[tint] = '\0';
#endif
return (new_list);
}
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