i-bash/examples/scripts.noah/send_mail.bash
2009-09-12 16:46:49 +00:00

140 lines
4.3 KiB
Bash

# send_mail.bash
# Author: Noah Friedman <friedman@prep.ai.mit.edu>
# Created: 1992-07-02
# Public domain
# Commentary:
# TODO: implement Fcc headers (see emacs manual)
# Code:
#:docstring send_mail:
# Usage: send_mail
#
# This function serves as a simple replacement for sendmail as a client
# interface on those systems where it is not available. It does assume
# that one can talk to an SMTP mailer on port 25 either on the local host
# or on the host specified by the MAILHOST environment variable. If you
# have access to sendmail, it's better to use 'sendmail -t' instead of this
# script (which probably isn't as robust).
#
# Message is read from stdin, and headers are parsed to determine
# recipients.
#:end docstring:
###;;;autoload
function send_mail ()
{
# Need gawk, since several extensions are taken advantage of (like
# IGNORECASE for regexps).
local awk="${GAWK_LOCATION:-gawk}"
local DefaultFrom="${USER:-${LOGNAME}}"
local From
local To
local Cc
local Bcc
local tmpfile="/tmp/send_mail$$"
while [ -e "${tmpfile}" ]; do
tmpfile="/tmp/send_mail${RANDOM}"
done
# Lines consisting only of dots need one more dot appended. SMTP
# servers eat one of the dots (and if only 1 dot appears, it signifies
# the end of the message).
sed '/^\.\.*/s/^\(\.\.*\)$/\1./' > "${tmpfile}"
# Parse mail headers in message to extract recipients list.
# This doesn't affect what the user sees---it's only used to generate
# the rcpt-to lines for SMTP.
eval $(${awk} -f - "${tmpfile}" <<- '__EOF__'
# Try to extract email address from amidst random data
function parse_address (data)
{
# From: "real name" <foobar@host>
# From: "" <foobar@host>
if (match(data, /^\"[^\"]*\"[ \t]*<.*>/)) {
data_idx = match(data, /^\"[^\"]*\"[ \t]*</)
data = substr(data, RSTART + RLENGTH);
if (data_idx = match(data, ">.*"))
data = substr(data, 1, RSTART - 1);
return data
}
# From: real name <foobar@host>
if (match(data, /<.*>/)) {
data_idx = match(data, /</)
data = substr(data, RSTART + RLENGTH);
if (data_idx = match(data, ">"))
data = substr(data, 1, RSTART - 1);
return data
}
# From: foobar@host (real name)
if (match(data, /\(.*\)/)) {
data_idx = match(data, /\(/);
data = substr(data, 1, RSTART - 1);
return data
}
# (hopefully) From: foobar@host
return data
}
BEGIN { IGNORECASE = 1; }
# Blank line signifies end of headers, so we can stop looking.
/^$/ { exit(0) }
/^from:|^to:|^cc:|^bcc:/ {
header_idx = match($0, /^[^:]*:/)
if (header_idx) {
# Capitalize header name
header_firstchar = toupper(substr($0, RSTART, 1));
header_rest = tolower(substr($0, RSTART + 1, RLENGTH - 2));
header = header_firstchar header_rest
$0 = substr($0, RSTART + RLENGTH + 1);
addresses = ""
# parse addresses
while ($0) {
# Strip leading whitespace
if (idx = match($0, /[ \t]*/))
$0 = substr($0, RSTART + RLENGTH);
# Find everything up to a nonquoted comma
# FIXME: doesnt handle quoting yet
if (idx = match($0, /,/)) {
data = substr($0, 1, RSTART);
$0 = substr($0, RSTART + 1);
} else {
data = $0
$0 = ""
}
addresses = addresses " " parse_address(data)
}
printf("%s='%s'\n", header, addresses);
}
}
__EOF__)
# Not sure if an address is *required* after the HELO.. every sendmail
# I tried talking to didn't seem to care. Some sendmails don't care
# if there's a HELO at all.
cat <<- __EOF__ | telnet ${MAILHOST:-localhost} 25 > /dev/null 2>&1
HELO
mail from: ${From:-${DefaultFrom}}
$(for name in ${To} ${Cc} ${Bcc} ; do
echo "rcpt to: ${name}"
done)
data
$(cat "${tmpfile}")
.
quit
__EOF__
rm -f "${tmpfile}"
}
provide send_mail
# send_mail.bash ends here