Fixed a bug Cal found on null termination of a result for memcached_fetch()

[awesomized/libmemcached] / lib / memcached_string.c

diff --git a/lib/memcached_string.c b/lib/memcached_string.c
index 63ffb59af03a152c9f5b5924f28100f873580bd3..247fbe475dd0506794add134d0c15bb47f3096db 100644 (file)
--- a/lib/memcached_string.c
+++ b/lib/memcached_string.c
@@ -2,79 +2,113 @@
 
 memcached_return memcached_string_check(memcached_string_st *string, size_t need)
 {
-  if (need > (size_t)(string->current_size - (size_t)(string->end - string->string)))
+  if (need && need > (size_t)(string->current_size - (size_t)(string->end - string->string)))
   {
     size_t current_offset= string->end - string->string;
     char *new_value;
+    size_t adjust;
+    size_t new_size;
 
-    new_value= (char *)realloc(string->string, sizeof(char) * string->block_size);
+    /* This is the block multiplier. To keep it larger and surive division errors we must round it up */
+    adjust= (need - (size_t)(string->current_size - (size_t)(string->end - string->string))) / string->block_size;
+    adjust++;
 
-    if (!new_value)
+    new_size= sizeof(char) * (size_t)((adjust * string->block_size) + string->current_size);
+    /* Test for overflow */
+    if (new_size < need)
+      return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
+
+    new_value= (char *)realloc(string->string, new_size);
+
+    if (new_value == NULL)
       return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 
     string->string= new_value;
     string->end= string->string + current_offset;
 
-    string->current_size+= string->block_size;
-
-    /* We zero the block structure we just realloced */
-    memset((string->string + string->current_size) - string->block_size , 0, 
-           sizeof(char) * string->block_size);
+    string->current_size+= (string->block_size * adjust);
   }
 
   return MEMCACHED_SUCCESS;
 }
 
-memcached_string_st *memcached_string_init(memcached_st *ptr, size_t initial_size)
+memcached_string_st *memcached_string_create(memcached_st *ptr, memcached_string_st *string, size_t initial_size)
 {
-  memcached_string_st *string;
+  memcached_return rc;
 
   /* Saving malloc calls :) */
-  string= (memcached_string_st *)malloc(sizeof(memcached_string_st) + (sizeof(char) * initial_size));
-  if (!string)
+  if (string)
+  {
+    memset(string, 0, sizeof(memcached_string_st));
+    string->is_allocated= MEMCACHED_NOT_ALLOCATED;
+  }
+  else
+  {
+    string= (memcached_string_st *)malloc(sizeof(memcached_string_st));
+    if (!string)
+      return NULL;
+    memset(string, 0, sizeof(memcached_string_st));
+    string->is_allocated= MEMCACHED_ALLOCATED;
+  }
+  string->block_size= MEMCACHED_BLOCK_SIZE;
+  string->root= ptr;
+
+  rc=  memcached_string_check(string, initial_size);
+  if (rc != MEMCACHED_SUCCESS)
+  {
+    free(string);
     return NULL;
-  memset(string, 0, sizeof(memcached_string_st));
-  string->block_size= initial_size;
-  memcached_string_check(string, initial_size);
+  }
+
+  WATCHPOINT_ASSERT(string->string == string->end);
 
   return string;
 }
 
-memcached_return memcached_string_append_character(memcached_st *ptr, 
-                                                   memcached_string_st *string, 
+memcached_return memcached_string_append_character(memcached_string_st *string, 
                                                    char character)
 {
-  memcached_string_check(string, 1);
+  memcached_return rc;
+
+  WATCHPOINT_ASSERT(string->is_allocated != MEMCACHED_USED);
+
+  rc=  memcached_string_check(string, 1);
+
+  if (rc != MEMCACHED_SUCCESS)
+    return rc;
+
   *string->end= ' ';
   string->end++;
 
   return MEMCACHED_SUCCESS;
 }
 
-memcached_return memcached_string_append(memcached_st *ptr, memcached_string_st *string,
+memcached_return memcached_string_append(memcached_string_st *string,
                                          char *value, size_t length)
 {
-  memcached_string_check(string, length);
+  memcached_return rc;
+
+  WATCHPOINT_ASSERT(string->is_allocated != MEMCACHED_USED);
+
+  rc= memcached_string_check(string, length);
+
+  if (rc != MEMCACHED_SUCCESS)
+    return rc;
+
+  WATCHPOINT_ASSERT(length <= string->current_size);
+  WATCHPOINT_ASSERT(string->string);
+  WATCHPOINT_ASSERT(string->end >= string->string);
+
   memcpy(string->end, value, length);
   string->end+= length;
 
   return MEMCACHED_SUCCESS;
 }
 
-#ifdef CRAP
-size_t memcached_string_length(memcached_st *ptr, memcached_string_st *string)
+size_t memcached_string_backspace(memcached_string_st *string, size_t remove)
 {
-  return (size_t)(string->end - string->string);
-}
+  WATCHPOINT_ASSERT(string->is_allocated != MEMCACHED_USED);
 
-size_t memcached_string_size(memcached_st *ptr, memcached_string_st *string)
-{
-  return string->current_size;
-}
-#endif
-
-size_t memcached_string_backspace(memcached_st *ptr, memcached_string_st *string, size_t remove)
-{
   if (string->end - string->string  > remove)
   {
     size_t difference;
@@ -89,15 +123,40 @@ size_t memcached_string_backspace(memcached_st *ptr, memcached_string_st *string
   return remove;
 }
 
-memcached_return memcached_string_reset(memcached_st *ptr, memcached_string_st *string)
+char *memcached_string_c_copy(memcached_string_st *string)
+{
+  char *c_ptr;
+
+  WATCHPOINT_ASSERT(string->is_allocated != MEMCACHED_USED);
+
+  c_ptr= (char *)malloc((memcached_string_length(string)+1) * sizeof(char));
+  if (!c_ptr)
+    return NULL;
+
+  memcpy(c_ptr, memcached_string_value(string), memcached_string_length(string));
+  c_ptr[memcached_string_length(string)]= 0;
+
+  return c_ptr;
+}
+
+memcached_return memcached_string_reset(memcached_string_st *string)
 {
+  WATCHPOINT_ASSERT(string->is_allocated != MEMCACHED_USED);
   string->end= string->string;
   
   return MEMCACHED_SUCCESS;
 }
 
-void memcached_string_free(memcached_st *ptr, memcached_string_st *string)
+void memcached_string_free(memcached_string_st *ptr)
 {
-  free(string->string);
-  free(string);
+  if (ptr == NULL)
+    return;
+
+  if (ptr->string)
+    free(ptr->string);
+
+  if (ptr->is_allocated == MEMCACHED_ALLOCATED)
+    free(ptr);
+  else
+    ptr->is_allocated= MEMCACHED_USED;
 }