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-rw-r--r--LibC/stdlib.cpp172
1 files changed, 0 insertions, 172 deletions
diff --git a/LibC/stdlib.cpp b/LibC/stdlib.cpp
index 656bd91ca7..17486f7c25 100644
--- a/LibC/stdlib.cpp
+++ b/LibC/stdlib.cpp
@@ -16,178 +16,6 @@
extern "C" {
-#define MALLOC_SCRUB_BYTE 0x85
-#define FREE_SCRUB_BYTE 0x82
-
-struct MallocHeader {
- uint16_t first_chunk_index;
- uint16_t chunk_count : 15;
- bool is_mmap : 1;
- size_t size;
-};
-
-#define CHUNK_SIZE 32
-#define POOL_SIZE 4 * 1048576
-
-static const size_t malloc_budget = POOL_SIZE;
-static byte s_malloc_map[POOL_SIZE / CHUNK_SIZE / 8];
-static byte* s_malloc_pool;
-
-static uint32_t s_malloc_sum_alloc = 0;
-static uint32_t s_malloc_sum_free = POOL_SIZE;
-
-static bool s_log_malloc = false;
-static bool s_scrub_malloc = true;
-static bool s_scrub_free = true;
-
-void* malloc(size_t size)
-{
- if (s_log_malloc)
- dbgprintf("LibC: malloc(%u)\n", size);
-
- if (size == 0)
- return nullptr;
-
- // We need space for the MallocHeader structure at the head of the block.
- size_t real_size = size + sizeof(MallocHeader);
-
- if (real_size >= PAGE_SIZE) {
- auto* memory = mmap(nullptr, real_size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
- if (memory == MAP_FAILED) {
- fprintf(stderr, "malloc() failed to mmap() for a %u-byte allocation: %s", size, strerror(errno));
- volatile char* crashme = (char*)0xf007d00d;
- *crashme = 0;
- return nullptr;
- }
- auto* header = (MallocHeader*)(memory);
- byte* ptr = ((byte*)header) + sizeof(MallocHeader);
- header->chunk_count = 0;
- header->first_chunk_index = 0;
- header->size = real_size;
- header->is_mmap = true;
- return ptr;
- }
-
- if (s_malloc_sum_free < real_size) {
- fprintf(stderr, "malloc(): Out of memory\ns_malloc_sum_free=%u, real_size=%u\n", s_malloc_sum_free, real_size);
- ASSERT_NOT_REACHED();
- }
-
- size_t chunks_needed = real_size / CHUNK_SIZE;
- if (real_size % CHUNK_SIZE)
- chunks_needed++;
-
- size_t chunks_here = 0;
- size_t first_chunk = 0;
-
- for (unsigned i = 0; i < (POOL_SIZE / CHUNK_SIZE / 8); ++i) {
- if (s_malloc_map[i] == 0xff) {
- // Skip over completely full bucket.
- chunks_here = 0;
- continue;
- }
-
- // FIXME: This scan can be optimized further with TZCNT.
- for (unsigned j = 0; j < 8; ++j) {
- if ((s_malloc_map[i] & (1<<j))) {
- // This is in use, so restart chunks_here counter.
- chunks_here = 0;
- continue;
- }
- if (chunks_here == 0) {
- // Mark where potential allocation starts.
- first_chunk = i * 8 + j;
- }
-
- ++chunks_here;
-
- if (chunks_here == chunks_needed) {
- auto* header = (MallocHeader*)(s_malloc_pool + (first_chunk * CHUNK_SIZE));
- byte* ptr = ((byte*)header) + sizeof(MallocHeader);
- header->chunk_count = chunks_needed;
- header->first_chunk_index = first_chunk;
- header->is_mmap = false;
- header->size = size;
-
- for (size_t k = first_chunk; k < (first_chunk + chunks_needed); ++k)
- s_malloc_map[k / 8] |= 1 << (k % 8);
-
- s_malloc_sum_alloc += header->chunk_count * CHUNK_SIZE;
- s_malloc_sum_free -= header->chunk_count * CHUNK_SIZE;
-
- if (s_scrub_malloc)
- memset(ptr, MALLOC_SCRUB_BYTE, (header->chunk_count * CHUNK_SIZE) - sizeof(MallocHeader));
- return ptr;
- }
- }
- }
-
- fprintf(stderr, "malloc(): Out of memory (no consecutive chunks found for size %u)\n", size);
- volatile char* crashme = (char*)0xc007d00d;
- *crashme = 0;
- return nullptr;
-}
-
-void free(void* ptr)
-{
- if (!ptr)
- return;
-
- auto* header = (MallocHeader*)((((byte*)ptr) - sizeof(MallocHeader)));
- if (header->is_mmap) {
- int rc = munmap(header, header->size);
- if (rc < 0)
- fprintf(stderr, "free(): munmap(%p) for allocation %p with size %u failed: %s\n", header, ptr, header->size, strerror(errno));
- return;
- }
-
- for (int i = header->first_chunk_index; i < (header->first_chunk_index + header->chunk_count); ++i)
- s_malloc_map[i / 8] &= ~(1 << (i % 8));
-
- s_malloc_sum_alloc -= header->chunk_count * CHUNK_SIZE;
- s_malloc_sum_free += header->chunk_count * CHUNK_SIZE;
-
- if (s_scrub_free)
- memset(header, FREE_SCRUB_BYTE, header->chunk_count * CHUNK_SIZE);
-}
-
-void __malloc_init()
-{
- s_malloc_pool = (byte*)mmap(nullptr, malloc_budget, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
- int rc = set_mmap_name(s_malloc_pool, malloc_budget, "malloc pool");
- if (rc < 0)
- perror("set_mmap_name failed");
-
- if (getenv("LIBC_NOSCRUB_MALLOC"))
- s_scrub_malloc = false;
- if (getenv("LIBC_NOSCRUB_FREE"))
- s_scrub_free = false;
- if (getenv("LIBC_LOG_MALLOC"))
- s_log_malloc = true;
-}
-
-void* calloc(size_t count, size_t size)
-{
- size_t new_size = count * size;
- auto* ptr = malloc(new_size);
- memset(ptr, 0, new_size);
- return ptr;
-}
-
-void* realloc(void *ptr, size_t size)
-{
- if (!ptr)
- return malloc(size);
- auto* header = (MallocHeader*)((((byte*)ptr) - sizeof(MallocHeader)));
- size_t old_size = header->size;
- if (size == old_size)
- return ptr;
- auto* new_ptr = malloc(size);
- memcpy(new_ptr, ptr, min(old_size, size));
- free(ptr);
- return new_ptr;
-}
-
typedef void(*__atexit_handler)();
static int __atexit_handler_count = 0;
static __atexit_handler __atexit_handlers[32];