diff options
| -rw-r--r-- | include/ogg/os_types.h | 13 | ||||
| -rw-r--r-- | src/bitwise.c | 6 |
2 files changed, 16 insertions, 3 deletions
diff --git a/include/ogg/os_types.h b/include/ogg/os_types.h index 4d4315d..cefd04f 100644 --- a/include/ogg/os_types.h +++ b/include/ogg/os_types.h @@ -24,6 +24,19 @@ #define _ogg_realloc realloc #define _ogg_free free +/* get non-brittle portable type-based MIN/MAX. Assumes 2's-complement + math */ +#define TYPE_HALF_MAX_SIGNED(type) \ + ((typeof(type))1 << (sizeof(type)*8-2)) +#define TYPE_MAX_SIGNED(type) \ + (TYPE_HALF_MAX_SIGNED(type) - 1 + TYPE_HALF_MAX_SIGNED(type)) +#define TYPE_MIN_SIGNED(type) \ + (-1 - TYPE_MAX_SIGNED(type)) +#define TYPE_MIN(type) \ + ((typeof(type))-1 < 1?TYPE_MIN_SIGNED(type):(typeof(type))0) +#define TYPE_MAX(type) \ + ((typeof(type))~TYPE_MIN(type)) + #if defined(_WIN32) # if defined(__CYGWIN__) diff --git a/src/bitwise.c b/src/bitwise.c index 48b7192..7a57f55 100644 --- a/src/bitwise.c +++ b/src/bitwise.c @@ -84,7 +84,7 @@ void oggpack_write(oggpack_buffer *b,unsigned long value,int bits){ if(b->endbyte>=b->storage-4){ void *ret; if(!b->ptr)return; - if(b->storage+BUFFER_INCREMENT<b->storage) goto err; + if(b->storage>TYPE_MAX(b->storage)-BUFFER_INCREMENT) goto err; ret=_ogg_realloc(b->buffer,b->storage+BUFFER_INCREMENT); if(!ret) goto err; b->buffer=ret; @@ -127,7 +127,7 @@ void oggpackB_write(oggpack_buffer *b,unsigned long value,int bits){ if(b->endbyte>=b->storage-4){ void *ret; if(!b->ptr)return; - if(b->storage+BUFFER_INCREMENT<b->storage) goto err; + if(b->storage>TYPE_MAX(b->storage)-BUFFER_INCREMENT) goto err; ret=_ogg_realloc(b->buffer,b->storage+BUFFER_INCREMENT); if(!ret) goto err; b->buffer=ret; @@ -198,7 +198,7 @@ static void oggpack_writecopy_helper(oggpack_buffer *b, if(b->endbyte+bytes+1>=b->storage){ void *ret; if(!b->ptr) goto err; - if(b->storage=b->endbyte+bytes+BUFFER_INCREMENT>b->storage) goto err; + if(b->endbyte+bytes+BUFFER_INCREMENT>b->storage) goto err; b->storage=b->endbyte+bytes+BUFFER_INCREMENT; ret=_ogg_realloc(b->buffer,b->storage); if(!ret) goto err; |