diff options
author | Jakob Kaivo <jkk@ung.org> | 2020-06-30 13:38:34 -0400 |
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committer | Jakob Kaivo <jkk@ung.org> | 2020-06-30 13:38:34 -0400 |
commit | bbac7666e763af9b65ef919b451f5930608a516a (patch) | |
tree | 20a307c9510352d55ac64314c83743b8e39405a5 | |
parent | 3c55d2c9a122091db77b735120c3bf5aa29722ad (diff) |
working realloc() (semi-working free())
-rw-r--r-- | src/mapalloc.c | 26 |
1 files changed, 17 insertions, 9 deletions
diff --git a/src/mapalloc.c b/src/mapalloc.c index 0744ebf..6d49f9d 100644 --- a/src/mapalloc.c +++ b/src/mapalloc.c @@ -54,19 +54,29 @@ static struct bucket *get_bucket(void *ptr, int allocate) static uintptr_t *trie_top = NULL; if (trie_top == NULL) { trie_top = page_alloc(1); + memset(trie_top, 0, PAGESIZE); } + printf("- finding bucket %p (%d)\n", ptr, allocate); uintptr_t *trie = trie_top; uintptr_t addr = (uintptr_t)ptr; for (size_t i = 0; i < sizeof(addr); i++) { - if (trie == NULL && allocate == 0) { - return NULL; + uintptr_t next = (addr >> ((sizeof(addr) - i) * CHAR_BIT)) + & UCHAR_MAX; + + printf("-- %02zx\n", next); + if (trie[next] == 0) { + if (allocate) { + uintptr_t *newtrie = page_alloc(1); + memset(newtrie, 0, PAGESIZE); + trie[next] = (uintptr_t) newtrie; + } else { + return NULL; + } } - - uintptr_t next = (addr >> (i * CHAR_BIT)) & UCHAR_MAX; trie = (uintptr_t*)trie[next]; } - return addr ? NULL : NULL; + return trie ? (struct bucket *)trie : NULL; } void *map_calloc(size_t nelem, size_t elsize) @@ -93,11 +103,9 @@ void *map_malloc(size_t nbytes) mprotect(ptr, PAGESIZE, PROT_NONE); mprotect(ptr + ((pages - 1) * PAGESIZE), PAGESIZE, PROT_NONE); - /* - struct bucket *b = get_bucket(ptr, 1); + struct bucket *b = get_bucket(ptr + PAGESIZE, 1); b->used = nbytes; b->allocated = pages * PAGESIZE; - */ return ptr + PAGESIZE; } @@ -122,7 +130,7 @@ void *map_realloc(void *ptr, size_t n) void *newptr = map_malloc(n); if (newptr != NULL) { - memcpy(newptr, ptr, n); + memcpy(newptr, ptr, b->used); map_free(ptr); } return newptr; |