[scan] Fix bug where playlist name isn't updated when m3u/pls file is renamed

Closes #1758

src/library/filescanner.c

@@ -166,6 +166,20 @@ filescanner_fullrescan();
 
 /* ----------------------- Internal utility functions --------------------- */
 
+static char *
+strip_extension(const char *path)
+{
+  char *ptr;
+  char *result;
+
+  result = strdup(path);
+  ptr = strrchr(result, '.');
+  if (ptr)
+    *ptr = '\0';
+
+  return result;
+}
+
 static int
 virtual_path_make(char *virtual_path, int virtual_path_len, const char *path)
 {
@@ -388,17 +402,13 @@ filename_from_path(const char *path)
 }
 
 char *
-strip_extension(const char *path)
+title_from_path(const char *path)
 {
-  char *ptr;
-  char *result;
+  const char *filename;
 
-  result = strdup(path);
-  ptr = strrchr(result, '.');
-  if (ptr)
-    *ptr = '\0';
+  filename = filename_from_path(path);
 
-  return result;
+  return strip_extension(filename);
 }
 
 int
@@ -425,12 +435,9 @@ parent_dir(const char **current, const char *path)
 int
 playlist_fill(struct playlist_info *pli, const char *path)
 {
-  const char *filename;
   char virtual_path[PATH_MAX];
   int ret;
 
-  filename = filename_from_path(path);
-
   ret = virtual_path_make(virtual_path, sizeof(virtual_path), path);
   if (ret < 0)
     return -1;
@@ -439,7 +446,7 @@ playlist_fill(struct playlist_info *pli, const char *path)
 
   pli->type  = PL_PLAIN;
   pli->path  = strdup(path);
-  pli->title = strip_extension(filename); // Will alloc
+  pli->title = title_from_path(path); // Will alloc
   pli->virtual_path = strip_extension(virtual_path); // Will alloc
   pli->scan_kind = SCAN_KIND_FILES;
 

src/library/filescanner.h

@@ -33,13 +33,14 @@ scan_itunes_itml(const char *file, time_t mtime, int dir_id);
 const char *
 filename_from_path(const char *path);
 
-/* Returns path without file extension. Caller must free result.
+/* Sets a title (=filename without extension and path) from a path. Caller must
+ * free the result.
  *
  * @in path        the complete path
- * @return         modified path
+ * @return         allocated title
  */
 char *
-strip_extension(const char *path);
+title_from_path(const char *path);
 
 /* Iterate up a file path.
  *

src/library/filescanner_playlist.c

@@ -371,6 +371,7 @@ static int
 playlist_prepare(const char *path, time_t mtime)
 {
   struct playlist_info *pli;
+  char *old_title;
   int pl_id;
 
   pli = db_pl_fetch_bypath(path);
@@ -389,7 +390,16 @@ playlist_prepare(const char *path, time_t mtime)
       return pl_id;
     }
 
-  db_pl_ping(pli->id);
+  // So we already have the playlist, but maybe it has been renamed
+  old_title = pli->title;
+  pli->title = title_from_path(path);
+
+  if (strcasecmp(old_title, pli->title) != 0)
+    db_pl_update(pli);
+  else
+    db_pl_ping(pli->id);
+
+  free(old_title);
 
   // mtime == db_timestamp is also treated as a modification because some editors do
   // stuff like 1) close the file with no changes (leading us to update db_timestamp),