*_free functions now accept NULL

Some *_free functions threw asserts when passed NULL. Now all of them
accept NULL as input and perform no action when called that way.

This gains us consistence for our free functions, and allows some
code simplifications where an explicit null check is no longer necessary.

1 files changed, 12 insertions, 7 deletions

diff --git a/src/or/buffers.c b/src/or/buffers.c
index 1a1b2077cc..7c40e47cca 100644
--- a/src/or/buffers.c
+++ b/src/or/buffers.c
@@ -147,10 +147,13 @@ get_freelist(size_t alloc)
 
 /** Deallocate a chunk or put it on a freelist */
 static void
-chunk_free(chunk_t *chunk)
+chunk_free_unchecked(chunk_t *chunk)
 {
-  size_t alloc = CHUNK_ALLOC_SIZE(chunk->memlen);
-  chunk_freelist_t *freelist = get_freelist(alloc);
+  size_t alloc;
+  chunk_freelist_t *freelist;
+
+  alloc = CHUNK_ALLOC_SIZE(chunk->memlen);
+  freelist = get_freelist(alloc);
   if (freelist && freelist->cur_length < freelist->max_length) {
     chunk->next = freelist->head;
     freelist->head = chunk;
@@ -195,7 +198,7 @@ chunk_new_with_alloc_size(size_t alloc)
 }
 #else
 static void
-chunk_free(chunk_t *chunk)
+chunk_free_unchecked(chunk_t *chunk)
 {
   tor_free(chunk);
 }
@@ -403,7 +406,7 @@ buf_pullup(buf_t *buf, size_t bytes, int nulterminate)
       dest->next = src->next;
       if (buf->tail == src)
         buf->tail = dest;
-      chunk_free(src);
+      chunk_free_unchecked(src);
     } else {
       memcpy(CHUNK_WRITE_PTR(dest), src->data, n);
       dest->datalen += n;
@@ -449,7 +452,7 @@ buf_remove_from_front(buf_t *buf, size_t n)
       buf->head = victim->next;
       if (buf->tail == victim)
         buf->tail = NULL;
-      chunk_free(victim);
+      chunk_free_unchecked(victim);
     }
   }
   check();
@@ -483,7 +486,7 @@ buf_clear(buf_t *buf)
   buf->datalen = 0;
   for (chunk = buf->head; chunk; chunk = next) {
     next = chunk->next;
-    chunk_free(chunk);
+    chunk_free_unchecked(chunk);
   }
   buf->head = buf->tail = NULL;
 }
@@ -522,6 +525,8 @@ buf_slack(const buf_t *buf)
 void
 buf_free(buf_t *buf)
 {
+  if (!buf)
+    return;
   buf_clear(buf);
   buf->magic = 0xdeadbeef;
   tor_free(buf);