Added missing file

src/test/SDL_test_memory.c

@@ -0,0 +1,274 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2017 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, 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 *SDLTest_TrackedMalloc(size_t size)
+{
+    void *mem;
+
+    mem = SDL_malloc_orig(size);
+    if (mem) {
+        SDL_TrackAllocation(mem, size);
+    }
+    return mem;
+}
+
+static void *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 *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 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: %lu bytes\n", count, 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%llx: %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: */