Changeset 1333

Timestamp:

Jun 1, 2007 7:26:21 AM (17 years ago)

Author:

bennylp

Message:

Implement ticket #314: Added PJ_SAFE_POOL configuration in PJLIB to track down memory corruptions

Location:

pjproject/trunk/pjlib

Files:

• include/pj/config.h (modified) (1 diff)
• src/pj/pool_caching.c (modified) (2 diffs)
• src/pj/pool_policy_malloc.c (modified) (3 diffs)
• src/pj/pool_policy_new.cpp (modified) (2 diffs)
• src/pj/pool_signature.h (added)

pjproject/trunk/pjlib/include/pj/config.h

@@ -389 +389 @@
 
 /**
+ * Set this flag to non-zero to enable various checking for pool
+ * operations. When this flag is set, assertion must be enabled
+ * in the application.
+ *
+ * This will slow down pool creation and destruction and will add
+ * few bytes of overhead, so application would normally want to 
+ * disable this feature on release build.
+ *
+ * Default: 0
+ */
+#ifndef PJ_SAFE_POOL
+#   define PJ_SAFE_POOL             0
+#endif
+
+
+/**
  * If pool debugging is used, then each memory allocation from the pool
  * will call malloc(), and pool will release all memory chunks when it

pjproject/trunk/pjlib/src/pj/pool_caching.c

@@ -100 +100 @@
         pj_pool_t *next = pool->next;
         pj_list_erase(pool);
+        PJ_LOG(4,(pool->obj_name, 
+                  "Pool is not released by application, releasing now"));
         pj_pool_destroy_int(pool);
         pool = next;
@@ -198 +200 @@
     PJ_CHECK_STACK();
 
+    PJ_ASSERT_ON_FAIL(pf && pool, return);
+
     pj_lock_acquire(cp->lock);
+
+#if PJ_SAFE_POOL
+    /* Make sure pool is still in our used list */
+    if (pj_list_find_node(&cp->used_list, pool) != pool) {
+        pj_assert(!"Attempt to destroy pool that has been destroyed before");
+        return;
+    }
+#endif
 
     /* Erase from the used list. */

pjproject/trunk/pjlib/src/pj/pool_policy_malloc.c

@@ -27 +27 @@
  * This file contains pool default policy definition and implementation.
  */
+#include "pool_signature.h"
 
 
@@ -42 +43 @@
     }
 
-    p = malloc(size);
+    p = malloc(size+(SIG_SIZE << 1));
 
     if (p == NULL) {
         if (factory->on_block_free) 
             factory->on_block_free(factory, size);
+    } else {
+        /* Apply signature when PJ_SAFE_POOL is set. It will move
+         * "p" pointer forward.
+         */
+        APPLY_SIG(p, size);
     }
 
@@ -59 +65 @@
     if (factory->on_block_free) 
         factory->on_block_free(factory, size);
+
+    /* Check and remove signature when PJ_SAFE_POOL is set. It will
+     * move "mem" pointer backward.
+     */
+    REMOVE_SIG(mem, size);
+
+    /* Note that when PJ_SAFE_POOL is set, the actual size of the block
+     * is size + SIG_SIZE*2.
+     */
 
     free(mem);

pjproject/trunk/pjlib/src/pj/pool_policy_new.cpp

@@ -26 +26 @@
  * This file contains pool default policy definition and implementation.
  */
+#include "pool_signature.h"
  
 
 static void *operator_new(pj_pool_factory *factory, pj_size_t size)
 {
+    void *mem;
+
     PJ_CHECK_STACK();
     PJ_UNUSED_ARG(factory);
     PJ_UNUSED_ARG(size);
 
-    return new char[size];
+    mem = (void*) new char[size+(SIG_SIZE << 1)];
+    
+    /* Exception for new operator may be disabled, so.. */
+    if (mem) {
+        /* Apply signature when PJ_SAFE_POOL is set. It will move
+         * "mem" pointer forward.
+         */
+        APPLY_SIG(mem, size);
+    }
+
+    return mem;
 }
 
@@ -42 +55 @@
     PJ_UNUSED_ARG(factory);
     PJ_UNUSED_ARG(size);
+
+    /* Check and remove signature when PJ_SAFE_POOL is set. It will
+     * move "mem" pointer backward.
+     */
+    REMOVE_SIG(mem, size);
+
+    /* Note that when PJ_SAFE_POOL is set, the actual size of the block
+     * is size + SIG_SIZE*2.
+     */
 
     char *p = (char*)mem;