fix bug where current chain length was not calculated all the time

diff --git a/src/libFLAC/metadata_iterators.c b/src/libFLAC/metadata_iterators.c
index 3f7e936..3fc3bef 100644 (file)
--- a/src/libFLAC/metadata_iterators.c
+++ b/src/libFLAC/metadata_iterators.c
@@ -709,11 +709,10 @@ struct FLAC__Metadata_Chain {
        long first_offset, last_offset; /*@@@ 2G limit */
        /*
         * This is the length of the chain initially read from the FLAC file.
-        * it is used to compare against the current_length to decide whether
+        * it is used to compare against the current length to decide whether
         * or not the whole file has to be rewritten.
         */
        unsigned initial_length; /*@@@ 4G limit */
-       unsigned current_length; /*@@@ 4G limit */
 };
 
 struct FLAC__Metadata_Iterator {
@@ -774,7 +773,6 @@ static void chain_append_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node
        }
        chain->tail = node;
        chain->nodes++;
-       chain->current_length += (FLAC__STREAM_METADATA_HEADER_LENGTH + node->data->length);
 }
 
 static void chain_remove_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node *node)
@@ -796,7 +794,6 @@ static void chain_remove_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node
                chain->tail->data->is_last = true;
 
        chain->nodes--;
-       chain->current_length -= (FLAC__STREAM_METADATA_HEADER_LENGTH + node->data->length);
 }
 
 static void chain_delete_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node *node)
@@ -805,6 +802,15 @@ static void chain_delete_node_(FLAC__Metadata_Chain *chain, FLAC__Metadata_Node
        node_delete_(node);
 }
 
+static unsigned chain_calculate_length_(FLAC__Metadata_Chain *chain)
+{
+       const FLAC__Metadata_Node *node;
+       unsigned length = 0;
+       for(node = chain->head; node; node = node->next)
+               length += (FLAC__STREAM_METADATA_HEADER_LENGTH + node->data->length);
+       return length;
+}
+
 static void iterator_insert_node_(FLAC__Metadata_Iterator *iterator, FLAC__Metadata_Node *node)
 {
        FLAC__ASSERT(0 != node);
@@ -828,7 +834,6 @@ static void iterator_insert_node_(FLAC__Metadata_Iterator *iterator, FLAC__Metad
        iterator->current->prev = node;
 
        iterator->chain->nodes++;
-       iterator->chain->current_length += (FLAC__STREAM_METADATA_HEADER_LENGTH + node->data->length);
 }
 
 static void iterator_insert_node_after_(FLAC__Metadata_Iterator *iterator, FLAC__Metadata_Node *node)
@@ -856,7 +861,6 @@ static void iterator_insert_node_after_(FLAC__Metadata_Iterator *iterator, FLAC_
        iterator->chain->tail->data->is_last = true;
 
        iterator->chain->nodes++;
-       iterator->chain->current_length += (FLAC__STREAM_METADATA_HEADER_LENGTH + node->data->length);
 }
 
 /* return true iff node and node->next are both padding */
@@ -865,7 +869,6 @@ static FLAC__bool chain_merge_adjacent_padding_(FLAC__Metadata_Chain *chain, FLA
        if(node->data->type == FLAC__METADATA_TYPE_PADDING && 0 != node->next && node->next->data->type == FLAC__METADATA_TYPE_PADDING) {
                const unsigned growth = FLAC__STREAM_METADATA_HEADER_LENGTH + node->next->data->length;
                node->data->length += growth;
-               chain->current_length += growth;
 
                chain_delete_node_(chain, node->next);
                return true;
@@ -883,7 +886,7 @@ FLAC__Metadata_Chain *FLAC__metadata_chain_new()
                chain->head = chain->tail = 0;
                chain->nodes = 0;
                chain->status = FLAC__METADATA_CHAIN_STATUS_OK;
-               chain->initial_length = chain->current_length = 0;
+               chain->initial_length = 0;
        }
 
        return chain;
@@ -966,7 +969,7 @@ FLAC__bool FLAC__metadata_chain_read(FLAC__Metadata_Chain *chain, const char *fi
        chain->last_offset = ftell(iterator->file) + iterator->length;
        FLAC__metadata_simple_iterator_delete(iterator);
 
-       chain->initial_length = chain->current_length;
+       chain->initial_length = chain_calculate_length_(chain);
        return true;
 }
 
@@ -974,22 +977,27 @@ FLAC__bool FLAC__metadata_chain_write(FLAC__Metadata_Chain *chain, FLAC__bool us
 {
        struct stat stats;
        const char *tempfile_path_prefix = 0;
+       unsigned current_length;
+
+       FLAC__ASSERT(0 != chain);
+
+       current_length = chain_calculate_length_(chain);
 
        if(use_padding) {
-               if(chain->current_length < chain->initial_length && chain->tail->data->type == FLAC__METADATA_TYPE_PADDING) {
-                       const unsigned delta = chain->initial_length - chain->current_length;
+               if(current_length < chain->initial_length && chain->tail->data->type == FLAC__METADATA_TYPE_PADDING) {
+                       const unsigned delta = chain->initial_length - current_length;
                        chain->tail->data->length += delta;
-                       chain->current_length += delta;
-                       FLAC__ASSERT(chain->current_length == chain->initial_length);
+                       current_length += delta;
+                       FLAC__ASSERT(current_length == chain->initial_length);
                }
-               else if(chain->current_length + FLAC__STREAM_METADATA_HEADER_LENGTH <= chain->initial_length) {
+               else if(current_length + FLAC__STREAM_METADATA_HEADER_LENGTH <= chain->initial_length) {
                        FLAC__StreamMetadata *padding;
                        FLAC__Metadata_Node *node;
                        if(0 == (padding = FLAC__metadata_object_new(FLAC__METADATA_TYPE_PADDING))) {
                                chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
                                return false;
                        }
-                       padding->length = chain->initial_length - (FLAC__STREAM_METADATA_HEADER_LENGTH + chain->current_length);
+                       padding->length = chain->initial_length - (FLAC__STREAM_METADATA_HEADER_LENGTH + current_length);
                        if(0 == (node = node_new_())) {
                                FLAC__metadata_object_delete(padding);
                                chain->status = FLAC__METADATA_CHAIN_STATUS_MEMORY_ALLOCATION_ERROR;
@@ -997,19 +1005,21 @@ FLAC__bool FLAC__metadata_chain_write(FLAC__Metadata_Chain *chain, FLAC__bool us
                        }
                        node->data = padding;
                        chain_append_node_(chain, node);
-                       FLAC__ASSERT(chain->current_length == chain->initial_length);
+                       current_length = chain_calculate_length_(chain);
+                       FLAC__ASSERT(current_length == chain->initial_length);
                }
-               else if(chain->current_length > chain->initial_length) {
-                       const unsigned delta = chain->current_length - chain->initial_length;
+               else if(current_length > chain->initial_length) {
+                       const unsigned delta = current_length - chain->initial_length;
                        if(chain->tail->data->type == FLAC__METADATA_TYPE_PADDING) {
                                if(chain->tail->data->length + FLAC__STREAM_METADATA_HEADER_LENGTH == delta) {
                                        chain_delete_node_(chain, chain->tail);
-                                       FLAC__ASSERT(chain->current_length == chain->initial_length);
+                                       current_length = chain_calculate_length_(chain);
+                                       FLAC__ASSERT(current_length == chain->initial_length);
                                }
                                else if(chain->tail->data->length >= delta) {
                                        chain->tail->data->length -= delta;
-                                       chain->current_length -= delta;
-                                       FLAC__ASSERT(chain->current_length == chain->initial_length);
+                                       current_length -= delta;
+                                       FLAC__ASSERT(current_length == chain->initial_length);
                                }
                        }
                }
@@ -1018,7 +1028,7 @@ FLAC__bool FLAC__metadata_chain_write(FLAC__Metadata_Chain *chain, FLAC__bool us
        if(preserve_file_stats)
                get_file_stats_(chain->filename, &stats);
 
-       if(chain->current_length == chain->initial_length) {
+       if(current_length == chain->initial_length) {
                if(!chain_rewrite_chain_(chain))
                        return false;
        }
@@ -1031,9 +1041,9 @@ FLAC__bool FLAC__metadata_chain_write(FLAC__Metadata_Chain *chain, FLAC__bool us
                set_file_stats_(chain->filename, &stats);
 
        /* recompute lengths and offsets if necessary */
-       if(chain->initial_length != chain->current_length) {
+       if(chain->initial_length != current_length) {
                const FLAC__Metadata_Node *node;
-               chain->initial_length = chain->current_length;
+               chain->initial_length = current_length;
                chain->last_offset = chain->first_offset;
                for(node = chain->head; node; node = node->next)
                        chain->last_offset += (FLAC__STREAM_METADATA_HEADER_LENGTH + node->data->length);