SDL_test_memory.c
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#include "SDL_config.h"
#include "SDL_assert.h"
#include "SDL_stdinc.h"
#include "SDL_log.h"
#include "SDL_test_crc32.h"
#include "SDL_test_memory.h"
#ifdef HAVE_LIBUNWIND_H
#include <libunwind.h>
#endif
/* This is a simple tracking allocator to demonstrate the use of SDL's
memory allocation replacement functionality.
It gets slow with large numbers of allocations and shouldn't be used
for production code.
*/
typedef struct SDL_tracked_allocation
{
void *mem;
size_t size;
Uint64 stack[10];
char stack_names[10][256];
struct SDL_tracked_allocation *next;
} SDL_tracked_allocation;
static SDLTest_Crc32Context s_crc32_context;
static SDL_malloc_func SDL_malloc_orig = NULL;
static SDL_calloc_func SDL_calloc_orig = NULL;
static SDL_realloc_func SDL_realloc_orig = NULL;
static SDL_free_func SDL_free_orig = NULL;
static int s_previous_allocations = 0;
static SDL_tracked_allocation *s_tracked_allocations[256];
static unsigned int get_allocation_bucket(void *mem)
{
CrcUint32 crc_value;
unsigned int index;
SDLTest_Crc32Calc(&s_crc32_context, (CrcUint8 *)&mem, sizeof(mem), &crc_value);
index = (crc_value & (SDL_arraysize(s_tracked_allocations) - 1));
return index;
}
static SDL_bool SDL_IsAllocationTracked(void *mem)
{
SDL_tracked_allocation *entry;
int index = get_allocation_bucket(mem);
for (entry = s_tracked_allocations[index]; entry; entry = entry->next) {
if (mem == entry->mem) {
return SDL_TRUE;
}
}
return SDL_FALSE;
}
static void SDL_TrackAllocation(void *mem, size_t size)
{
SDL_tracked_allocation *entry;
int index = get_allocation_bucket(mem);
if (SDL_IsAllocationTracked(mem)) {
return;
}
entry = (SDL_tracked_allocation *)SDL_malloc_orig(sizeof(*entry));
if (!entry) {
return;
}
entry->mem = mem;
entry->size = size;
/* Generate the stack trace for the allocation */
SDL_zero(entry->stack);
#ifdef HAVE_LIBUNWIND_H
{
int stack_index;
unw_cursor_t cursor;
unw_context_t context;
unw_getcontext(&context);
unw_init_local(&cursor, &context);
stack_index = 0;
while (unw_step(&cursor) > 0) {
unw_word_t offset, pc;
char sym[256];
unw_get_reg(&cursor, UNW_REG_IP, &pc);
entry->stack[stack_index] = pc;
if (unw_get_proc_name(&cursor, sym, sizeof(sym), &offset) == 0) {
snprintf(entry->stack_names[stack_index], sizeof(entry->stack_names[stack_index]), "%s+0x%llx", sym, (unsigned long long)offset);
}
++stack_index;
if (stack_index == SDL_arraysize(entry->stack)) {
break;
}
}
}
#endif /* HAVE_LIBUNWIND_H */
entry->next = s_tracked_allocations[index];
s_tracked_allocations[index] = entry;
}
static void SDL_UntrackAllocation(void *mem)
{
SDL_tracked_allocation *entry, *prev;
int index = get_allocation_bucket(mem);
prev = NULL;
for (entry = s_tracked_allocations[index]; entry; entry = entry->next) {
if (mem == entry->mem) {
if (prev) {
prev->next = entry->next;
} else {
s_tracked_allocations[index] = entry->next;
}
SDL_free_orig(entry);
return;
}
prev = entry;
}
}
static void * SDLCALL SDLTest_TrackedMalloc(size_t size)
{
void *mem;
mem = SDL_malloc_orig(size);
if (mem) {
SDL_TrackAllocation(mem, size);
}
return mem;
}
static void * SDLCALL SDLTest_TrackedCalloc(size_t nmemb, size_t size)
{
void *mem;
mem = SDL_calloc_orig(nmemb, size);
if (mem) {
SDL_TrackAllocation(mem, nmemb * size);
}
return mem;
}
static void * SDLCALL SDLTest_TrackedRealloc(void *ptr, size_t size)
{
void *mem;
SDL_assert(!ptr || SDL_IsAllocationTracked(ptr));
mem = SDL_realloc_orig(ptr, size);
if (mem && mem != ptr) {
if (ptr) {
SDL_UntrackAllocation(ptr);
}
SDL_TrackAllocation(mem, size);
}
return mem;
}
static void SDLCALL SDLTest_TrackedFree(void *ptr)
{
if (!ptr) {
return;
}
if (!s_previous_allocations) {
SDL_assert(SDL_IsAllocationTracked(ptr));
}
SDL_UntrackAllocation(ptr);
SDL_free_orig(ptr);
}
int SDLTest_TrackAllocations()
{
if (SDL_malloc_orig) {
return 0;
}
SDLTest_Crc32Init(&s_crc32_context);
s_previous_allocations = SDL_GetNumAllocations();
if (s_previous_allocations != 0) {
SDL_Log("SDLTest_TrackAllocations(): There are %d previous allocations, disabling free() validation", s_previous_allocations);
}
SDL_GetMemoryFunctions(&SDL_malloc_orig,
&SDL_calloc_orig,
&SDL_realloc_orig,
&SDL_free_orig);
SDL_SetMemoryFunctions(SDLTest_TrackedMalloc,
SDLTest_TrackedCalloc,
SDLTest_TrackedRealloc,
SDLTest_TrackedFree);
return 0;
}
void SDLTest_LogAllocations()
{
char *message = NULL;
size_t message_size = 0;
char line[128], *tmp;
SDL_tracked_allocation *entry;
int index, count, stack_index;
Uint64 total_allocated;
if (!SDL_malloc_orig) {
return;
}
#define ADD_LINE() \
message_size += (SDL_strlen(line) + 1); \
tmp = (char *)SDL_realloc_orig(message, message_size); \
if (!tmp) { \
return; \
} \
message = tmp; \
SDL_strlcat(message, line, message_size)
SDL_strlcpy(line, "Memory allocations:\n", sizeof(line));
ADD_LINE();
SDL_strlcpy(line, "Expect 2 allocations from within SDL_GetErrBuf()\n", sizeof(line));
ADD_LINE();
count = 0;
total_allocated = 0;
for (index = 0; index < SDL_arraysize(s_tracked_allocations); ++index) {
for (entry = s_tracked_allocations[index]; entry; entry = entry->next) {
SDL_snprintf(line, sizeof(line), "Allocation %d: %d bytes\n", count, (int)entry->size);
ADD_LINE();
/* Start at stack index 1 to skip our tracking functions */
for (stack_index = 1; stack_index < SDL_arraysize(entry->stack); ++stack_index) {
if (!entry->stack[stack_index]) {
break;
}
SDL_snprintf(line, sizeof(line), "\t0x%"SDL_PRIx64": %s\n", entry->stack[stack_index], entry->stack_names[stack_index]);
ADD_LINE();
}
total_allocated += entry->size;
++count;
}
}
SDL_snprintf(line, sizeof(line), "Total: %.2f Kb in %d allocations\n", (float)total_allocated / 1024, count);
ADD_LINE();
#undef ADD_LINE
SDL_Log("%s", message);
}
/* vi: set ts=4 sw=4 expandtab: */
SDL_zero
#define SDL_zero(x)
Definition: SDL_stdinc.h:416
SDL_realloc_func
void *(* SDL_realloc_func)(void *mem, size_t size)
Definition: SDL_stdinc.h:368
SDLTest_Crc32Context
Definition: SDL_test_crc32.h:66
SDL_IsAllocationTracked
static SDL_bool SDL_IsAllocationTracked(void *mem)
Definition: SDL_test_memory.c:65
SDL_strlcpy
#define SDL_strlcpy
Definition: SDL_dynapi_overrides.h:394
offset
GLintptr offset
Definition: SDL_opengl_glext.h:538
SDL_calloc_func
void *(* SDL_calloc_func)(size_t nmemb, size_t size)
Definition: SDL_stdinc.h:367
NULL
#define NULL
Definition: begin_code.h:167
message
GLuint GLsizei const GLchar * message
Definition: SDL_opengl_glext.h:2483
SDL_PRIx64
#define SDL_PRIx64
Definition: SDL_stdinc.h:249
SDL_log.h
SDLTest_TrackedRealloc
static void * SDLTest_TrackedRealloc(void *ptr, size_t size)
Definition: SDL_test_memory.c:169
count
GLuint GLuint GLsizei count
Definition: SDL_opengl.h:1571
SDLCALL
#define SDLCALL
Definition: SDL_internal.h:49
SDL_SetMemoryFunctions
#define SDL_SetMemoryFunctions
Definition: SDL_dynapi_overrides.h:641
s_previous_allocations
static int s_previous_allocations
Definition: SDL_test_memory.c:53
SDL_tracked_allocation::stack
Uint64 stack[10]
Definition: SDL_test_memory.c:43
index
GLuint index
Definition: SDL_opengl_glext.h:660
SDL_realloc_orig
static SDL_realloc_func SDL_realloc_orig
Definition: SDL_test_memory.c:51
SDL_UntrackAllocation
static void SDL_UntrackAllocation(void *mem)
Definition: SDL_test_memory.c:127
SDL_FALSE
@ SDL_FALSE
Definition: SDL_stdinc.h:163
context
static screen_context_t context
Definition: video.c:25
SDL_free_func
void(* SDL_free_func)(void *mem)
Definition: SDL_stdinc.h:369
SDL_Log
#define SDL_Log
Definition: SDL_dynapi_overrides.h:31
ADD_LINE
#define ADD_LINE()
SDL_assert.h
s_tracked_allocations
static SDL_tracked_allocation * s_tracked_allocations[256]
Definition: SDL_test_memory.c:54
s_crc32_context
static SDLTest_Crc32Context s_crc32_context
Definition: SDL_test_memory.c:48
SDL_assert
#define SDL_assert(condition)
Definition: SDL_assert.h:169
get_allocation_bucket
static unsigned int get_allocation_bucket(void *mem)
Definition: SDL_test_memory.c:56
SDL_malloc_orig
static SDL_malloc_func SDL_malloc_orig
Definition: SDL_test_memory.c:49
SDLTest_TrackAllocations
int SDLTest_TrackAllocations()
Start tracking SDL memory allocations.
Definition: SDL_test_memory.c:197
SDL_tracked_allocation
Definition: SDL_test_memory.c:39
cursor
SDL_Cursor * cursor
Definition: testwm2.c:40
SDL_test_crc32.h
size
GLsizeiptr size
Definition: SDL_opengl_glext.h:537
SDLTest_Crc32Init
int SDLTest_Crc32Init(SDLTest_Crc32Context *crcContext)
Initialize the CRC context.
Definition: SDL_test_crc32.c:34
SDL_arraysize
#define SDL_arraysize(array)
Definition: SDL_stdinc.h:115
SDL_GetMemoryFunctions
#define SDL_GetMemoryFunctions
Definition: SDL_dynapi_overrides.h:640
SDL_tracked_allocation::next
struct SDL_tracked_allocation * next
Definition: SDL_test_memory.c:45
SDL_malloc_func
void *(* SDL_malloc_func)(size_t size)
Definition: SDL_stdinc.h:366
SDL_TRUE
@ SDL_TRUE
Definition: SDL_stdinc.h:164
SDL_snprintf
#define SDL_snprintf
Definition: SDL_dynapi_overrides.h:40
Uint64
uint64_t Uint64
Definition: SDL_stdinc.h:216
SDL_tracked_allocation::size
size_t size
Definition: SDL_test_memory.c:42
SDL_stdinc.h
CrcUint32
#define CrcUint32
Definition: SDL_test_crc32.h:51
SDL_test_memory.h
SDL_free_orig
static SDL_free_func SDL_free_orig
Definition: SDL_test_memory.c:52
SDL_tracked_allocation::mem
void * mem
Definition: SDL_test_memory.c:41
SDLTest_LogAllocations
void SDLTest_LogAllocations()
Print a log of any outstanding allocations.
Definition: SDL_test_memory.c:222
SDL_tracked_allocation::stack_names
char stack_names[10][256]
Definition: SDL_test_memory.c:44
SDL_GetNumAllocations
#define SDL_GetNumAllocations
Definition: SDL_dynapi_overrides.h:642
SDLTest_TrackedCalloc
static void * SDLTest_TrackedCalloc(size_t nmemb, size_t size)
Definition: SDL_test_memory.c:158
SDLTest_TrackedMalloc
static void * SDLTest_TrackedMalloc(size_t size)
Definition: SDL_test_memory.c:147
SDLTest_TrackedFree
static void SDLTest_TrackedFree(void *ptr)
Definition: SDL_test_memory.c:184
SDL_calloc_orig
static SDL_calloc_func SDL_calloc_orig
Definition: SDL_test_memory.c:50
SDL_TrackAllocation
static void SDL_TrackAllocation(void *mem, size_t size)
Definition: SDL_test_memory.c:77
CrcUint8
#define CrcUint8
Definition: SDL_test_crc32.h:54
SDL_bool
SDL_bool
Definition: SDL_stdinc.h:161
SDLTest_Crc32Calc
int SDLTest_Crc32Calc(SDLTest_Crc32Context *crcContext, CrcUint8 *inBuf, CrcUint32 inLen, CrcUint32 *crc32)
calculate a crc32 from a data block
Definition: SDL_test_crc32.c:72