116 lines
		
	
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			116 lines
		
	
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* table.h - definitions for tables for keeping track of allocated memory */
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| 
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| /*  Copyright (C) 2001-2003 Free Software Foundation, Inc.
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| 
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|     This file is part of GNU Bash, the Bourne-Again SHell.
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| 
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|    Bash is free software: you can redistribute it and/or modify
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|    it under the terms of the GNU General Public License as published by
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|    the Free Software Foundation, either version 3 of the License, or
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|    (at your option) any later version.
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| 
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|    Bash is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|    GNU General Public License for more details.
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| 
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|    You should have received a copy of the GNU General Public License
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|    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
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| */
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| 
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| #ifndef _MTABLE_H
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| #define _MTABLE_H
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| 
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| #include "imalloc.h"
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| 
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| #ifdef MALLOC_REGISTER
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| 
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| /* values for flags byte. */
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| #define MT_ALLOC	0x01
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| #define MT_FREE		0x02
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| 
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| /*
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|  * Memory table entry.
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|  *
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|  * MEM is the address of the allocated pointer.
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|  * SIZE is the requested allocation size.
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|  * FLAGS includes either MT_ALLOC (MEM is allocated) or MT_FREE (MEM is
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|  * not allocated).  Other flags later.
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|  * FUNC is set to the name of the function doing the allocation (from the
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|  * `tag' argument to register_alloc().
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|  * FILE and LINE are the filename and line number of the last allocation
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|  * and free (depending on STATUS) of MEM.
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|  * NALLOC and NFREE are incremented on each allocation that returns MEM or
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|  * each free of MEM, respectively (way to keep track of memory reuse
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|  * and how well the free lists are working).
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|  *
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|  */
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| typedef struct mr_table {
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| 	PTR_T mem;
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| 	size_t size;
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| 	char flags;
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| 	const char *func;
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| 	const char *file;
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| 	int line;
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| 	int nalloc, nfree;
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| } mr_table_t;
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| 
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| #define REG_TABLE_SIZE	8192
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| 
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| extern mr_table_t *mr_table_entry __P((PTR_T));
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| extern void mregister_alloc __P((const char *, PTR_T, size_t, const char *, int));
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| extern void mregister_free __P((PTR_T, int, const char *, int));
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| extern void mregister_describe_mem ();
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| extern void mregister_dump_table __P((void));
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| extern void mregister_table_init __P((void));
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| 
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| typedef struct ma_table {
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| 	const char *file;
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| 	int line;
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| 	int nalloc;
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| } ma_table_t;
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| 
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| extern void mlocation_register_alloc __P((const char *, int));
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| extern void mlocation_table_init __P((void));
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| extern void mlocation_dump_table __P((void));
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| extern void mlocation_write_table __P((void));
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| 
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| /* NOTE:  HASH_MIX taken from dmalloc (http://dmalloc.com) */
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| 
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| /*
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|  * void HASH_MIX
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|  *
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|  * DESCRIPTION:
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|  *
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|  * Mix 3 32-bit values reversibly.  For every delta with one or two
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|  * bits set, and the deltas of all three high bits or all three low
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|  * bits, whether the original value of a,b,c is almost all zero or is
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|  * uniformly distributed.
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|  *
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|  * If HASH_MIX() is run forward or backward, at least 32 bits in a,b,c
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|  * have at least 1/4 probability of changing.  If mix() is run
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|  * forward, every bit of c will change between 1/3 and 2/3 of the
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|  * time.  (Well, 22/100 and 78/100 for some 2-bit deltas.)
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|  *
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|  * HASH_MIX() takes 36 machine instructions, but only 18 cycles on a
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|  * superscalar machine (like a Pentium or a Sparc).  No faster mixer
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|  * seems to work, that's the result of my brute-force search.  There
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|  * were about 2^68 hashes to choose from.  I only tested about a
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|  * billion of those.
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|  */
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| #define HASH_MIX(a, b, c) \
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|  do { \
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|    a -= b; a -= c; a ^= (c >> 13); \
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|    b -= c; b -= a; b ^= (a << 8); \
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|    c -= a; c -= b; c ^= (b >> 13); \
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|    a -= b; a -= c; a ^= (c >> 12); \
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|    b -= c; b -= a; b ^= (a << 16); \
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|    c -= a; c -= b; c ^= (b >> 5); \
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|    a -= b; a -= c; a ^= (c >> 3); \
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|    b -= c; b -= a; b ^= (a << 10); \
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|    c -= a; c -= b; c ^= (b >> 15); \
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|  } while(0)
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| 
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| #endif /* MALLOC_REGISTER */
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| 
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| #endif /* _MTABLE_H */
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