diff options
| -rw-r--r-- | include/lib/mem.h | 3 | ||||
| -rw-r--r-- | src/lib/mem.c | 50 |
2 files changed, 47 insertions, 6 deletions
diff --git a/include/lib/mem.h b/include/lib/mem.h index 646a170..529ecea 100644 --- a/include/lib/mem.h +++ b/include/lib/mem.h @@ -5,6 +5,7 @@ #define MEM_USE_OFFSET 1 #define MEM_BASE_SIZE 2 #define MEM_META_SIZE 3 +#define NULL 0 struct MemTab { unsigned char size; @@ -29,8 +30,10 @@ void memset32(unsigned long* dest, unsigned long value, unsigned int n); void memcpy32(unsigned long* src, unsigned long* dest, unsigned int n); unsigned char memcmp32(unsigned long* a, unsigned long* b, unsigned int n); +void* realloc(void* old, unsigned char size); void* malloc(unsigned char size); void* calloc(unsigned char size); +void* realloca(void* old, unsigned char size, unsigned char amnt); void* malloca(unsigned char size, unsigned char amnt); void* calloca(unsigned char size, unsigned char amnt); void free(void* memloc); diff --git a/src/lib/mem.c b/src/lib/mem.c index e51ec32..bc5f23c 100644 --- a/src/lib/mem.c +++ b/src/lib/mem.c @@ -76,7 +76,7 @@ unsigned char memcmp32(unsigned long* a, unsigned long* b, unsigned int n) static unsigned char rpi_heap[MAX_MM] = {0,}; static void* rpi_heap_top = &rpi_heap; -// TODO: Put size at end and cleanup from tail + void* malloc(unsigned char size) { unsigned char* mem = (unsigned char*)rpi_heap; @@ -85,6 +85,8 @@ void* malloc(unsigned char size) while (((void*)(mem + i) < rpi_heap_top) && !(mem[i + MEM_SIZE_OFFSET] == size && mem[i + MEM_USE_OFFSET]==0)) { i += mem[i] + MEM_META_SIZE; } + if (mem + i >= (unsigned char*)(rpi_heap_top + MAX_MM)) + return NULL; // Update top of heap if (mem[i] == 0) rpi_heap_top = (void*)&mem[i + MEM_META_SIZE + size]; @@ -98,8 +100,23 @@ void* malloc(unsigned char size) void* calloc(unsigned char size) { void* addr = malloc(size); - memset(addr, 0, size); - return addr; + if (addr != NULL) { + memset(addr, 0, size); + return addr; + } + return NULL; +} +void* realloc(void* old, unsigned char size) +{ + unsigned char osize = *(unsigned char*)(old - MEM_BASE_SIZE); + if (size <= osize) + return old; + void* new = malloc(size); + if (new != NULL) { + free(old); + return new; + } + return NULL; } void* malloca(unsigned char size, unsigned char amnt) @@ -110,7 +127,7 @@ void* malloca(unsigned char size, unsigned char amnt) unsigned char* mem = (unsigned char*)rpi_heap; unsigned long i = 0; // TODO: Use Null PID - while(1) { + while(mem + i < rpi_heap + MAX_MM) { unsigned long diff = (unsigned long)mem + i + MEM_BASE_SIZE; diff %= amnt; diff = amnt - diff; @@ -134,6 +151,10 @@ void* malloca(unsigned char size, unsigned char amnt) diff += amnt; } unsigned long empty_size = diff - MEM_META_SIZE; + if(empty_size == 0) { + empty_size += amnt; + diff += amnt; + } mem[i + MEM_SIZE_OFFSET] = empty_size; mem[i + MEM_BASE_SIZE + empty_size] = empty_size; i += diff; @@ -147,13 +168,30 @@ void* malloca(unsigned char size, unsigned char amnt) i += mem[i] + MEM_META_SIZE; } + return NULL; } void* calloca(unsigned char size, unsigned char amnt) { void* addr = malloca(size, amnt); - memset(addr, 0, size); - return addr; + if (addr != NULL) { + memset(addr, 0, size); + return addr; + } + return NULL; +} + +void* realloca(void* old, unsigned char size, unsigned char amnt) +{ + unsigned char osize = *(unsigned char*)(old - MEM_BASE_SIZE); + if (size <= osize) + return old; + void* new = malloca(size, amnt); + if (new != NULL) { + free(old); + return new; + } + return NULL; } void free(void* memloc) |