data: Improved memory handling in data_copy().

Ensure that dynamic memory in the destination is freed before copying the new
data. That'll avoid that the caller has to use data_free_datum() first and
destroy previous data even if the copy fails.

diff --git a/src/core/data.c b/src/core/data.c
index dc2d0ae8afde4dbb741bc2525444fddad05ed0a8..beba5a7a4006011dc51838d7f7a5bdd57fa9c846 100644 (file)
--- a/src/core/data.c
+++ b/src/core/data.c
@@ -65,6 +65,7 @@ sdb_data_copy(sdb_data_t *dst, const sdb_data_t *src)
                        break;
        }
 
+       sdb_data_free_datum(dst);
        *dst = tmp;
        return 0;
 } /* sdb_data_copy */

diff --git a/src/core/store.c b/src/core/store.c
index 3885e5064f22931ba4791642108b4eda26aebe85..8b284e77378bba680ead5d0edc8854049305a955 100644 (file)
--- a/src/core/store.c
+++ b/src/core/store.c
@@ -532,10 +532,8 @@ sdb_store_attribute(const char *hostname,
 
        if (status >= 0) {
                assert(updated_attr);
-               sdb_data_free_datum(&ATTR(updated_attr)->value);
-               if (sdb_data_copy(&ATTR(updated_attr)->value, value)) {
+               if (sdb_data_copy(&ATTR(updated_attr)->value, value))
                        status = -1;
-               }
        }
 
        pthread_rwlock_unlock(&host_lock);

diff --git a/src/include/core/data.h b/src/include/core/data.h
index 879af9087db92d7346fee2109326df55eaf25dfc..d6bf3179eb39ddb4cb6d2c74b36bc4f718216cb0 100644 (file)
--- a/src/include/core/data.h
+++ b/src/include/core/data.h
@@ -81,7 +81,8 @@ typedef struct {
  * Copy the datum stored in 'src' to the memory location pointed to by 'dst'.
  * Any dynamic data (strings, binary data) is copied to newly allocated
  * memory. Use, for example, sdb_data_free_datum() to free any dynamic memory
- * stored in a datum.
+ * stored in a datum. On error, 'dst' is unchanged. Else, any dynamic memory
+ * in 'dst' will be freed.
  *
  * Returns:
  *  - 0 on success