From 6ebad5d9496eef6c2f1ad843198bb0413be6e16f Mon Sep 17 00:00:00 2001
From: Brian Aker <brian@tangent.org>
Date: Fri, 17 Jun 2011 16:22:47 -0700
Subject: [PATCH] Just hand over memory ownership when the caller is supposed
 to free it (we have before this made a copy and used the previous as a
 buffer).

---
 libmemcached/fetch.cc  |  2 +-
 libmemcached/get.cc    |  3 +--
 libmemcached/string.cc | 29 +++++++++++++++++++++++++++++
 libmemcached/string.h  |  3 +++
 tests/mem_functions.cc | 18 ++++++++++--------
 5 files changed, 44 insertions(+), 11 deletions(-)

diff --git a/libmemcached/fetch.cc b/libmemcached/fetch.cc
index 5a353d29..e947ddb2 100644
--- a/libmemcached/fetch.cc
+++ b/libmemcached/fetch.cc
@@ -115,7 +115,7 @@ char *memcached_fetch(memcached_st *ptr, char *key, size_t *key_length,
   if (flags)
     *flags= result_buffer->item_flags;
 
-  return memcached_string_c_copy(&result_buffer->value);
+  return memcached_string_take_value(&result_buffer->value);
 }
 
 memcached_result_st *memcached_fetch_result(memcached_st *ptr,
diff --git a/libmemcached/get.cc b/libmemcached/get.cc
index bcc468a0..b95aa0c1 100644
--- a/libmemcached/get.cc
+++ b/libmemcached/get.cc
@@ -111,7 +111,6 @@ char *memcached_get_by_key(memcached_st *ptr,
   {
     if (ptr->get_key_failure && *error == MEMCACHED_NOTFOUND)
     {
-
       memcached_result_reset(&ptr->result);
       memcached_return_t rc= ptr->get_key_failure(ptr, key, key_length, &ptr->result);
 
@@ -148,7 +147,7 @@ char *memcached_get_by_key(memcached_st *ptr,
           *error= rc;
           *value_length= memcached_result_length(&ptr->result);
           *flags= memcached_result_flags(&ptr->result);
-          return memcached_string_c_copy(&ptr->result.value);
+          return memcached_string_take_value(&ptr->result.value);
         }
       }
     }
diff --git a/libmemcached/string.cc b/libmemcached/string.cc
index 9e029627..6f3b9c1c 100644
--- a/libmemcached/string.cc
+++ b/libmemcached/string.cc
@@ -37,6 +37,7 @@
 
 
 #include <libmemcached/common.h>
+#include <cassert>
 
 inline static memcached_return_t _string_check(memcached_string_st *string, size_t need)
 {
@@ -118,6 +119,18 @@ memcached_string_st *memcached_string_create(memcached_st *memc, memcached_strin
   return self;
 }
 
+static memcached_return_t memcached_string_append_null(memcached_string_st *string)
+{
+  if (memcached_failed(_string_check(string, 1)))
+  {
+    return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
+  }
+
+  *string->end= 0;
+
+  return MEMCACHED_SUCCESS;
+}
+
 memcached_return_t memcached_string_append_character(memcached_string_st *string,
                                                      char character)
 {
@@ -213,6 +226,22 @@ const char *memcached_string_value(const memcached_string_st *self)
   return self->string;
 }
 
+char *memcached_string_take_value(memcached_string_st *self)
+{
+  assert(self);
+  // If we fail at adding the null, we copy and move on
+  if (memcached_success(memcached_string_append_null(self)))
+  {
+    return memcached_string_c_copy(self);
+  }
+
+  char *value= self->string;
+
+  _init_string(self);
+
+  return value;
+}
+
 char *memcached_string_value_mutable(const memcached_string_st *self)
 {
   return self->string;
diff --git a/libmemcached/string.h b/libmemcached/string.h
index a0b66ed3..3a3fdf53 100644
--- a/libmemcached/string.h
+++ b/libmemcached/string.h
@@ -97,6 +97,9 @@ size_t memcached_string_size(const memcached_string_st *self);
 LIBMEMCACHED_LOCAL
 const char *memcached_string_value(const memcached_string_st *self);
 
+LIBMEMCACHED_LOCAL
+char *memcached_string_take_value(memcached_string_st *self);
+
 LIBMEMCACHED_LOCAL
 char *memcached_string_value_mutable(const memcached_string_st *self);
 
diff --git a/tests/mem_functions.cc b/tests/mem_functions.cc
index 1b07d9c8..589d5cb3 100644
--- a/tests/mem_functions.cc
+++ b/tests/mem_functions.cc
@@ -954,7 +954,8 @@ static test_return_t read_through(memcached_st *memc)
                         &string_length, &flags, &rc);
 
   test_compare(MEMCACHED_SUCCESS, rc);
-  test_compare(string_length, strlen(READ_THROUGH_VALUE));
+  test_compare(string_length, sizeof(READ_THROUGH_VALUE) -1);
+  test_true(string[sizeof(READ_THROUGH_VALUE) -1] == 0);
   test_strcmp(READ_THROUGH_VALUE, string);
   free(string);
 
@@ -962,7 +963,9 @@ static test_return_t read_through(memcached_st *memc)
                         &string_length, &flags, &rc);
 
   test_compare(MEMCACHED_SUCCESS, rc);
-  test_compare(string_length, strlen(READ_THROUGH_VALUE));
+  test_true(string);
+  test_compare(string_length, sizeof(READ_THROUGH_VALUE) -1);
+  test_true(string[sizeof(READ_THROUGH_VALUE) -1] == 0);
   test_strcmp(READ_THROUGH_VALUE, string);
   free(string);
 
@@ -2802,7 +2805,6 @@ static test_return_t user_supplied_bug15(memcached_st *memc)
   uint32_t x;
   memcached_return_t rc;
   const char *key= "mykey";
-  char *value;
   size_t length;
   uint32_t flags;
 
@@ -2814,13 +2816,13 @@ static test_return_t user_supplied_bug15(memcached_st *memc)
 
     test_compare(MEMCACHED_SUCCESS, rc);
 
-    value= memcached_get(memc, key, strlen(key),
-                         &length, &flags, &rc);
+    char *value= memcached_get(memc, key, strlen(key),
+                               &length, &flags, &rc);
 
     test_compare(MEMCACHED_SUCCESS, rc);
-    test_true(value == NULL);
-    test_true(length == 0);
-    test_true(flags == 0);
+    test_false(value);
+    test_false(length);
+    test_false(flags);
 
     value= memcached_get(memc, key, strlen(key),
                          &length, &flags, &rc);
-- 
2.30.2