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/*--------------------------------------------------------------------*/
/*--- malloc/free wrappers for detecting errors and updating bits. ---*/
/*--- mac_malloc_wrappers.c ---*/
/*--------------------------------------------------------------------*/
/*
This file is part of MemCheck, a heavyweight Valgrind tool for
detecting memory errors, and AddrCheck, a lightweight Valgrind tool
for detecting memory errors.
Copyright (C) 2000-2003 Julian Seward
jseward@acm.org
This program 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 of the
License, or (at your option) any later version.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
#include "mac_shared.h"
/*------------------------------------------------------------*/
/*--- Defns ---*/
/*------------------------------------------------------------*/
/* Stats ... */
static UInt cmalloc_n_mallocs = 0;
static UInt cmalloc_n_frees = 0;
static UInt cmalloc_bs_mallocd = 0;
/* We want a 16B redzone on heap blocks for Addrcheck and Memcheck */
UInt VG_(vg_malloc_redzone_szB) = 16;
/* Function pointers for the two skins to track interesting events. */
void (*MAC_(new_mem_heap)) ( Addr a, UInt len, Bool is_inited ) = NULL;
void (*MAC_(ban_mem_heap)) ( Addr a, UInt len ) = NULL;
void (*MAC_(die_mem_heap)) ( Addr a, UInt len ) = NULL;
void (*MAC_(copy_mem_heap))( Addr from, Addr to, UInt len ) = NULL;
/* Function pointers for internal sanity checking. */
Bool (*MAC_(check_noaccess))( Addr a, UInt len, Addr* bad_addr ) = NULL;
/*------------------------------------------------------------*/
/*--- Tracking malloc'd and free'd blocks ---*/
/*------------------------------------------------------------*/
/* Record malloc'd blocks. Nb: Addrcheck and Memcheck construct this
separately in their respective initialisation functions. */
VgHashTable MAC_(malloc_list) = NULL;
/* Records blocks after freeing. */
static MAC_Chunk* freed_list_start = NULL;
static MAC_Chunk* freed_list_end = NULL;
static Int freed_list_volume = 0;
/* Put a shadow chunk on the freed blocks queue, possibly freeing up
some of the oldest blocks in the queue at the same time. */
static void add_to_freed_queue ( MAC_Chunk* mc )
{
MAC_Chunk* sc1;
/* Put it at the end of the freed list */
if (freed_list_end == NULL) {
sk_assert(freed_list_start == NULL);
freed_list_end = freed_list_start = mc;
freed_list_volume = mc->size;
} else {
sk_assert(freed_list_end->next == NULL);
freed_list_end->next = mc;
freed_list_end = mc;
freed_list_volume += mc->size;
}
mc->next = NULL;
/* Release enough of the oldest blocks to bring the free queue
volume below vg_clo_freelist_vol. */
while (freed_list_volume > MAC_(clo_freelist_vol)) {
sk_assert(freed_list_start != NULL);
sk_assert(freed_list_end != NULL);
sc1 = freed_list_start;
freed_list_volume -= sc1->size;
/* VG_(printf)("volume now %d\n", freed_list_volume); */
sk_assert(freed_list_volume >= 0);
if (freed_list_start == freed_list_end) {
freed_list_start = freed_list_end = NULL;
} else {
freed_list_start = sc1->next;
}
sc1->next = NULL; /* just paranoia */
/* free MAC_Chunk */
VG_(cli_free) ( (void*)(sc1->data) );
VG_(free) ( sc1 );
}
}
/* Return the first shadow chunk satisfying the predicate p. */
MAC_Chunk* MAC_(first_matching_freed_MAC_Chunk) ( Bool (*p)(MAC_Chunk*) )
{
MAC_Chunk* mc;
/* No point looking through freed blocks if we're not keeping
them around for a while... */
for (mc = freed_list_start; mc != NULL; mc = mc->next)
if (p(mc))
return mc;
return NULL;
}
/* Allocate its shadow chunk, put it on the appropriate list. */
static
void add_MAC_Chunk ( Addr p, UInt size, MAC_AllocKind kind )
{
MAC_Chunk* mc;
mc = VG_(malloc)(sizeof(MAC_Chunk));
mc->data = p;
mc->size = size;
mc->allockind = kind;
mc->where = VG_(get_ExeContext)(VG_(get_current_or_recent_tid)());
/* Paranoia ... ensure this area is off-limits to the client, so
the mc->data field isn't visible to the leak checker. If memory
management is working correctly, anything pointer returned by
VG_(malloc) should be noaccess as far as the client is
concerned. */
if (!MAC_(check_noaccess)( (Addr)mc, sizeof(MAC_Chunk), NULL )) {
VG_(skin_panic)("add_MAC_chunk: shadow area is accessible");
}
VG_(HT_add_node)( MAC_(malloc_list), (VgHashNode*)mc );
}
/*------------------------------------------------------------*/
/*--- client_malloc(), etc ---*/
/*------------------------------------------------------------*/
/* Allocate memory and note change in memory available */
__inline__
void MAC_(new_block) ( Addr p, UInt size,
UInt rzB, Bool is_zeroed, MAC_AllocKind kind )
{
VGP_PUSHCC(VgpCliMalloc);
cmalloc_n_mallocs ++;
cmalloc_bs_mallocd += size;
add_MAC_Chunk( p, size, kind );
MAC_(ban_mem_heap)( p-rzB, rzB );
MAC_(new_mem_heap)( p, size, is_zeroed );
MAC_(ban_mem_heap)( p+size, rzB );
VGP_POPCC(VgpCliMalloc);
}
void* SK_(malloc) ( Int n )
{
if (n < 0) {
VG_(message)(Vg_UserMsg, "Warning: silly arg (%d) to malloc()", n );
return NULL;
} else {
Addr p = (Addr)VG_(cli_malloc)( VG_(clo_alignment), n );
MAC_(new_block) ( p, n, VG_(vg_malloc_redzone_szB),
/*is_zeroed*/False, MAC_AllocMalloc );
return (void*)p;
}
}
void* SK_(__builtin_new) ( Int n )
{
if (n < 0) {
VG_(message)(Vg_UserMsg, "Warning: silly arg (%d) to __builtin_new()", n);
return NULL;
} else {
Addr p = (Addr)VG_(cli_malloc)( VG_(clo_alignment), n );
MAC_(new_block) ( p, n, VG_(vg_malloc_redzone_szB),
/*is_zeroed*/False, MAC_AllocNew );
return (void*)p;
}
}
void* SK_(__builtin_vec_new) ( Int n )
{
if (n < 0) {
VG_(message)(Vg_UserMsg,
"Warning: silly arg (%d) to __builtin_vec_new()", n );
return NULL;
} else {
Addr p = (Addr)VG_(cli_malloc)( VG_(clo_alignment), n );
MAC_(new_block) ( p, n, VG_(vg_malloc_redzone_szB),
/*is_zeroed*/False, MAC_AllocNewVec );
return (void*)p;
}
}
void* SK_(memalign) ( Int align, Int n )
{
if (n < 0) {
VG_(message)(Vg_UserMsg, "Warning: silly arg (%d) to memalign()", n);
return NULL;
} else {
Addr p = (Addr)VG_(cli_malloc)( align, n );
MAC_(new_block) ( p, n, VG_(vg_malloc_redzone_szB),
/*is_zeroed*/False, MAC_AllocMalloc );
return (void*)p;
}
}
void* SK_(calloc) ( Int nmemb, Int size1 )
{
Int n, i;
n = nmemb * size1;
if (nmemb < 0 || size1 < 0) {
VG_(message)(Vg_UserMsg, "Warning: silly args (%d,%d) to calloc()",
nmemb, size1 );
return NULL;
} else {
Addr p = (Addr)VG_(cli_malloc)( VG_(clo_alignment), n );
MAC_(new_block) ( p, n, VG_(vg_malloc_redzone_szB),
/*is_zeroed*/True, MAC_AllocMalloc );
for (i = 0; i < n; i++)
((UChar*)p)[i] = 0;
return (void*)p;
}
}
static
void die_and_free_mem ( MAC_Chunk* mc,
MAC_Chunk** prev_chunks_next_ptr, UInt rzB )
{
/* Note: ban redzones again -- just in case user de-banned them
with a client request... */
MAC_(ban_mem_heap)( mc->data-rzB, rzB );
MAC_(die_mem_heap)( mc->data, mc->size );
MAC_(ban_mem_heap)( mc->data+mc->size, rzB );
/* Remove mc from the malloclist using prev_chunks_next_ptr to
avoid repeating the hash table lookup. Can't remove until at least
after free and free_mismatch errors are done because they use
describe_addr() which looks for it in malloclist. */
*prev_chunks_next_ptr = mc->next;
/* Record where freed */
mc->where = VG_(get_ExeContext) ( VG_(get_current_or_recent_tid)() );
/* Put it out of harm's way for a while, if not from a client request */
if (MAC_AllocCustom != mc->allockind)
add_to_freed_queue ( mc );
else
VG_(free) ( mc );
}
__inline__
void MAC_(handle_free) ( Addr p, UInt rzB, MAC_AllocKind kind )
{
MAC_Chunk* mc;
MAC_Chunk** prev_chunks_next_ptr;
ThreadId tid = VG_(get_current_or_recent_tid)();
VGP_PUSHCC(VgpCliMalloc);
cmalloc_n_frees++;
mc = (MAC_Chunk*)VG_(HT_get_node) ( MAC_(malloc_list), (UInt)p,
(VgHashNode***)&prev_chunks_next_ptr );
if (mc == NULL) {
MAC_(record_free_error) ( tid, p );
VGP_POPCC(VgpCliMalloc);
return;
}
/* check if its a matching free() / delete / delete [] */
if (kind != mc->allockind) {
MAC_(record_freemismatch_error) ( tid, p );
}
die_and_free_mem ( mc, prev_chunks_next_ptr, rzB );
VGP_POPCC(VgpCliMalloc);
}
void SK_(free) ( void* p )
{
MAC_(handle_free)((Addr)p, VG_(vg_malloc_redzone_szB), MAC_AllocMalloc);
}
void SK_(__builtin_delete) ( void* p )
{
MAC_(handle_free)((Addr)p, VG_(vg_malloc_redzone_szB), MAC_AllocNew);
}
void SK_(__builtin_vec_delete) ( void* p )
{
MAC_(handle_free)((Addr)p, VG_(vg_malloc_redzone_szB), MAC_AllocNewVec);
}
void* SK_(realloc) ( void* p, Int new_size )
{
MAC_Chunk *mc;
MAC_Chunk **prev_chunks_next_ptr;
UInt i;
ThreadId tid = VG_(get_current_or_recent_tid)();
VGP_PUSHCC(VgpCliMalloc);
cmalloc_n_frees ++;
cmalloc_n_mallocs ++;
cmalloc_bs_mallocd += new_size;
if (new_size < 0) {
VG_(message)(Vg_UserMsg,
"Warning: silly arg (%d) to realloc()", new_size );
return NULL;
}
/* First try and find the block. */
mc = (MAC_Chunk*)VG_(HT_get_node) ( MAC_(malloc_list), (UInt)p,
(VgHashNode***)&prev_chunks_next_ptr );
if (mc == NULL) {
MAC_(record_free_error) ( tid, (Addr)p );
/* Perhaps we should return to the program regardless. */
VGP_POPCC(VgpCliMalloc);
return NULL;
}
/* check if its a matching free() / delete / delete [] */
if (MAC_AllocMalloc != mc->allockind) {
/* can not realloc a range that was allocated with new or new [] */
MAC_(record_freemismatch_error) ( tid, (Addr)p );
/* but keep going anyway */
}
if (mc->size == new_size) {
/* size unchanged */
mc->where = VG_(get_ExeContext)(tid);
VGP_POPCC(VgpCliMalloc);
return p;
} else if (mc->size > new_size) {
/* new size is smaller */
MAC_(die_mem_heap)( mc->data+new_size, mc->size-new_size );
mc->size = new_size;
mc->where = VG_(get_ExeContext)(tid);
VGP_POPCC(VgpCliMalloc);
return p;
} else {
/* new size is bigger */
Addr p_new;
/* Get new memory */
p_new = (Addr)VG_(cli_malloc)(VG_(clo_alignment), new_size);
/* First half kept and copied, second half new,
red zones as normal */
MAC_(ban_mem_heap) ( p_new-VG_(vg_malloc_redzone_szB),
VG_(vg_malloc_redzone_szB) );
MAC_(copy_mem_heap)( (Addr)p, p_new, mc->size );
MAC_(new_mem_heap) ( p_new+mc->size, new_size-mc->size, /*inited*/False );
MAC_(ban_mem_heap) ( p_new+new_size, VG_(vg_malloc_redzone_szB) );
/* Copy from old to new */
for (i = 0; i < mc->size; i++)
((UChar*)p_new)[i] = ((UChar*)p)[i];
/* Free old memory */
die_and_free_mem ( mc, prev_chunks_next_ptr,
VG_(vg_malloc_redzone_szB) );
/* this has to be after die_and_free_mem, otherwise the
former succeeds in shorting out the new block, not the
old, in the case when both are on the same list. */
add_MAC_Chunk ( p_new, new_size, MAC_AllocMalloc );
VGP_POPCC(VgpCliMalloc);
return (void*)p_new;
}
}
void MAC_(print_malloc_stats) ( void )
{
UInt nblocks = 0, nbytes = 0;
/* Mmm... more lexical scoping */
void count_one_chunk(VgHashNode* node) {
MAC_Chunk* mc = (MAC_Chunk*)node;
nblocks ++;
nbytes += mc->size;
}
if (VG_(clo_verbosity) == 0)
return;
/* Count memory still in use. */
VG_(HT_apply_to_all_nodes)(MAC_(malloc_list), count_one_chunk);
VG_(message)(Vg_UserMsg,
"malloc/free: in use at exit: %d bytes in %d blocks.",
nbytes, nblocks);
VG_(message)(Vg_UserMsg,
"malloc/free: %d allocs, %d frees, %u bytes allocated.",
cmalloc_n_mallocs,
cmalloc_n_frees, cmalloc_bs_mallocd);
if (VG_(clo_verbosity) > 1)
VG_(message)(Vg_UserMsg, "");
}
/*--------------------------------------------------------------------*/
/*--- end mac_malloc_wrappers.c ---*/
/*--------------------------------------------------------------------*/