diff options
Diffstat (limited to 'modules/music-config.el')
| -rw-r--r-- | modules/music-config.el | 45 |
1 files changed, 33 insertions, 12 deletions
diff --git a/modules/music-config.el b/modules/music-config.el index 92b04782..47863e41 100644 --- a/modules/music-config.el +++ b/modules/music-config.el @@ -677,18 +677,39 @@ M3U-FILE should be an existing, writable M3U file path." (unless (file-writable-p m3u-file) (error "M3U file is not writable: %s" m3u-file)) - ;; Convert absolute path to relative path from music root - (let ((relative-path (if (file-name-absolute-p track-path) - (file-relative-name track-path cj/music-root) - track-path))) - ;; Determine if we need a leading newline - (let ((needs-prefix-newline nil) - (file-size (file-attribute-size (file-attributes m3u-file)))) - (when (> file-size 0) - ;; Read the last character of the file to check if it ends with newline - (with-temp-buffer - (insert-file-contents m3u-file nil (max 0 (1- file-size)) file-size) - (setq needs-prefix-newline (not (= (char-after (point-min)) ?\n))))) + ;; Relative when the track sits under the playlist's own directory, absolute + ;; otherwise. + ;; + ;; The base is the playlist rather than `cj/music-root' because that is what + ;; both readers resolve against -- `cj/music--m3u-file-tracks' and EMMS's + ;; `emms-source-playlist-parse-m3u'. Inside the music root the two are the + ;; same directory, which is why basing on the root went unnoticed: it only + ;; wrote an unresolvable line once a playlist lived somewhere else. + ;; + ;; Falling back to absolute keeps a cross-tree reference readable, and it + ;; survives the playlist being moved again. A playlist in the mpd directory + ;; pointing into ~/music would otherwise carry a four-level ../ chain that + ;; breaks the moment anything moves. + (let* ((dir (file-name-directory m3u-file)) + (relative-path + (if (not (file-name-absolute-p track-path)) + track-path + (let ((rel (file-relative-name track-path dir))) + (if (string-prefix-p "../" rel) track-path rel))))) + ;; Does the file need a separating newline first? Read the content and look + ;; at its last character, rather than seeking to a byte offset derived from + ;; `file-attributes'. That call does not follow symlinks, so on a + ;; stow-deployed playlist it measures the link string instead of the file: + ;; every symlinked playlist read the wrong byte and gained a blank line per + ;; append, and where the link string was the longer of the two the range fell + ;; outside the file entirely and the append died on a nil `char-after'. + ;; Playlists are small text files, so reading one is cheaper than being + ;; clever about offsets. + (let ((needs-prefix-newline + (with-temp-buffer + (insert-file-contents m3u-file) + (and (> (buffer-size) 0) + (/= (char-before (point-max)) ?\n))))) ;; Append the track with proper newline handling (with-temp-buffer |