X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/51ce67d59968560f0e975dc97bb0a22a7edb0610..0566dc54b18fcaa6d666711ec3356bf6096af87e:/lib/pool_alloc.c

diff --git a/lib/pool_alloc.c b/lib/pool_alloc.c
index c48e4c97..4c76d356 100644
--- a/lib/pool_alloc.c
+++ b/lib/pool_alloc.c
@@ -2,7 +2,7 @@
 
 #define POOL_DEF_EXTENT	(32 * 1024)
 
-#define POOL_QALIGN_P2	(1<<16)
+#define POOL_QALIGN_P2		(1<<16)		/* power-of-2 qalign	*/
 
 struct alloc_pool
 {
@@ -24,10 +24,10 @@ struct alloc_pool
 
 struct pool_extent
 {
+	struct pool_extent	*next;
 	void			*start;		/* starting address	*/
 	size_t			free;		/* free bytecount	*/
 	size_t			bound;		/* trapped free bytes	*/
-	struct pool_extent	*next;
 };
 
 struct align_test {
@@ -72,8 +72,8 @@ pool_create(size_t size, size_t quantum, void (*bomb)(const char *), int flags)
 	}
 
 	if (quantum <= 1)
-		flags &= ~(POOL_QALIGN | POOL_QALIGN_P2);
-	else if (flags & POOL_QALIGN) {
+		flags = (flags | POOL_NO_QALIGN) & ~POOL_QALIGN_P2;
+	else if (!(flags & POOL_NO_QALIGN)) {
 		if (size % quantum)
 			size += quantum - size % quantum;
 		/* If quantum is a power of 2, we'll avoid using modulus. */
@@ -101,7 +101,7 @@ pool_destroy(alloc_pool_t p)
 	for (cur = pool->extents; cur; cur = next) {
 		next = cur->next;
 		if (pool->flags & POOL_PREPEND)
-			free(cur->start - sizeof (struct pool_extent));
+			free(PTR_ADD(cur->start, -sizeof (struct pool_extent)));
 		else {
 			free(cur->start);
 			free(cur);
@@ -123,7 +123,7 @@ pool_alloc(alloc_pool_t p, size_t len, const char *bomb_msg)
 	else if (pool->flags & POOL_QALIGN_P2) {
 		if (len & (pool->quantum - 1))
 			len += pool->quantum - (len & (pool->quantum - 1));
-	} else if (pool->flags & POOL_QALIGN) {
+	} else if (!(pool->flags & POOL_NO_QALIGN)) {
 		if (len % pool->quantum)
 			len += pool->quantum - len % pool->quantum;
 	}
@@ -148,7 +148,7 @@ pool_alloc(alloc_pool_t p, size_t len, const char *bomb_msg)
 
 		if (pool->flags & POOL_PREPEND) {
 			ext = start;
-			start += sizeof (struct pool_extent);
+			start = PTR_ADD(start, sizeof (struct pool_extent));
 		} else if (!(ext = new(struct pool_extent)))
 			goto bomb_out;
 		ext->start = start;
@@ -185,12 +185,21 @@ pool_free(alloc_pool_t p, size_t len, void *addr)
 	if (!pool)
 		return;
 
+	if (!addr) {
+		/* A NULL addr starts a fresh extent for new allocations. */
+		if ((cur = pool->extents) != NULL && cur->free != pool->size) {
+			cur->bound += cur->free;
+			cur->free = 0;
+		}
+		return;
+	}
+
 	if (!len)
 		len = pool->quantum;
 	else if (pool->flags & POOL_QALIGN_P2) {
 		if (len & (pool->quantum - 1))
 			len += pool->quantum - (len & (pool->quantum - 1));
-	} else if (pool->flags & POOL_QALIGN) {
+	} else if (!(pool->flags & POOL_NO_QALIGN)) {
 		if (len % pool->quantum)
 			len += pool->quantum - len % pool->quantum;
 	}
@@ -227,7 +236,7 @@ pool_free(alloc_pool_t p, size_t len, void *addr)
 		if (cur->free + cur->bound >= pool->size) {
 			prev->next = cur->next;
 			if (pool->flags & POOL_PREPEND)
-				free(cur->start - sizeof (struct pool_extent));
+				free(PTR_ADD(cur->start, -sizeof (struct pool_extent)));
 			else {
 				free(cur->start);
 				free(cur);
@@ -284,7 +293,7 @@ pool_free_old(alloc_pool_t p, void *addr)
 	while ((cur = next) != NULL) {
 		next = cur->next;
 		if (pool->flags & POOL_PREPEND)
-			free(cur->start - sizeof (struct pool_extent));
+			free(PTR_ADD(cur->start, -sizeof (struct pool_extent)));
 		else {
 			free(cur->start);
 			free(cur);