From ff7ac2d9a0e5873d897379d7851e72c9874bc9ca Mon Sep 17 00:00:00 2001
From: Krisztian Litkey <kli@iki.fi>
Date: Sat, 2 Mar 2013 00:25:28 +0200
Subject: [PATCH] common: handle realloc to 0 size gracefully as free in debug
 mode.

---
 src/common/mm.c | 78 +++++++++++++++++++++++++++++++--------------------------
 1 file changed, 42 insertions(+), 36 deletions(-)

diff --git a/src/common/mm.c b/src/common/mm.c
index f50570d..4bda3d8 100644
--- a/src/common/mm.c
+++ b/src/common/mm.c
@@ -157,6 +157,28 @@ static memblk_t *memblk_alloc(size_t size, const char *file, int line,
 }
 
 
+static void memblk_free(memblk_t *blk, const char *file, int line,
+                        const char *func, void **bt)
+{
+    MRP_UNUSED(file);
+    MRP_UNUSED(line);
+    MRP_UNUSED(func);
+    MRP_UNUSED(bt);
+
+    if (blk != NULL) {
+        mrp_list_delete(&blk->hook);
+
+        __mm.cur_blocks--;
+        __mm.cur_alloc -= blk->size;
+
+        if (__mm.poison != 0)
+            memset(&blk->bt[__mm.depth], __mm.poison, blk->size);
+
+        free(blk);
+    }
+}
+
+
 static memblk_t *memblk_resize(memblk_t *blk, size_t size, const char *file,
                                int line, const char *func, void **bt)
 {
@@ -165,27 +187,33 @@ static memblk_t *memblk_resize(memblk_t *blk, size_t size, const char *file,
     if (blk != NULL) {
         mrp_list_delete(&blk->hook);
 
-        resized = realloc(blk, __mm.hdrsize + size);
+        if (size != 0) {
+            resized = realloc(blk, __mm.hdrsize + size);
 
-        if (resized != NULL) {
-            mrp_list_init(&resized->hook);
+            if (resized != NULL) {
+                mrp_list_init(&resized->hook);
 
-            mrp_list_append(&__mm.blocks, &resized->hook);
+                mrp_list_append(&__mm.blocks, &resized->hook);
 
-            __mm.cur_alloc -= resized->size;
-            __mm.cur_alloc += size;
-            __mm.max_alloc  = MRP_MAX(__mm.max_alloc, __mm.cur_alloc);
+                __mm.cur_alloc -= resized->size;
+                __mm.cur_alloc += size;
+                __mm.max_alloc  = MRP_MAX(__mm.max_alloc, __mm.cur_alloc);
 
-            resized->file = file;
-            resized->line = line;
-            resized->func = func;
+                resized->file = file;
+                resized->line = line;
+                resized->func = func;
 
-            memcpy(resized->bt, bt, __mm.depth * sizeof(*bt));
+                memcpy(resized->bt, bt, __mm.depth * sizeof(*bt));
 
-            resized->size = size;
+                resized->size = size;
+            }
+            else
+                mrp_list_append(&__mm.blocks, &blk->hook);
+        }
+        else {
+            resized = NULL;
+            memblk_free(blk, file, line, func, bt);
         }
-        else
-            mrp_list_append(&__mm.blocks, &blk->hook);
 
         return resized;
     }
@@ -194,28 +222,6 @@ static memblk_t *memblk_resize(memblk_t *blk, size_t size, const char *file,
 }
 
 
-static void memblk_free(memblk_t *blk, const char *file, int line,
-                        const char *func, void **bt)
-{
-    MRP_UNUSED(file);
-    MRP_UNUSED(line);
-    MRP_UNUSED(func);
-    MRP_UNUSED(bt);
-
-    if (blk != NULL) {
-        mrp_list_delete(&blk->hook);
-
-        __mm.cur_blocks--;
-        __mm.cur_alloc -= blk->size;
-
-        if (__mm.poison != 0)
-            memset(&blk->bt[__mm.depth], __mm.poison, blk->size);
-
-        free(blk);
-    }
-}
-
-
 static inline void *memblk_to_ptr(memblk_t *blk)
 {
     if (blk != NULL)
-- 
2.7.4