mpd.c

   1 /*-
   2  * "THE BEER-WARE LICENSE" (Revision 42):
   3  * <tobias.rehbein@web.de> wrote this file. As long as you retain this notice
   4  * you can do whatever you want with this stuff. If we meet some day, and you
   5  * think this stuff is worth it, you can buy me a beer in return.
   6  *                                                              Tobias Rehbein
   7  */
   8
   9 #define _POSIX_C_SOURCE 199506
  10
  11 #include <assert.h>
  12 #include <err.h>
  13 #include <iconv.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include <time.h>
  18 #include <sysexits.h>
  19
  20 #include <mpd/connection.h>
  21 #include <mpd/error.h>
  22 #include <mpd/player.h>
  23 #include <mpd/song.h>
  24 #include <mpd/status.h>
  25 #include <mpd/tag.h>
  26
  27 #include "buffers.h"
  28 #include "mpd.h"
  29 #include "tools.h"
  30
  31 enum {
  32         SLEEP = 5,
  33 };
  34
  35 const char     *NOTAVAILABLE = "n/a";
  36 const char     *NOARTIST = "unknown artist";
  37 const char     *NOTITLE = "unknown title";
  38
  39 struct mpd_context {
  40         struct mpd_connection *conn;
  41         char            mpd_utf[MPD_BUFFLEN];
  42         char            mpd_str[MPD_BUFFLEN];
  43         iconv_t         cd;
  44         time_t          last;
  45 };
  46
  47 struct mpd_context *
  48 mpd_context_open()
  49 {
  50         struct mpd_context *ctx;
  51
  52         if ((ctx = malloc(sizeof(*ctx))) == NULL)
  53                 err(EX_SOFTWARE, "malloc(%d) mpd_context", sizeof(*ctx));
  54
  55         if ((ctx->cd = iconv_open("", "UTF-8")) == (iconv_t) (-1))
  56                 err(EX_SOFTWARE, "iconv_open");
  57
  58         ctx->conn = NULL;
  59         ctx->mpd_str[0] = '\0';
  60         ctx->mpd_utf[0] = '\0';
  61         ctx->last = time(NULL) - SLEEP;
  62
  63         return (ctx);
  64 }
  65
  66 void
  67 mpd_context_close(struct mpd_context *ctx)
  68 {
  69         assert(ctx != NULL);
  70
  71         if (iconv_close(ctx->cd) == -1)
  72                 err(EX_SOFTWARE, "iconv_close");
  73
  74         if (ctx->conn != NULL)
  75                 mpd_connection_free(ctx->conn);
  76
  77         free(ctx);
  78 }
  79
  80 char           *
  81 mpd_str(struct mpd_context *ctx)
  82 {
  83         struct mpd_song *song = NULL;
  84         struct mpd_status *status = NULL;
  85         const char     *artist, *title;
  86         char           *in, *out;
  87         size_t          inleft, outleft;
  88         time_t          now;
  89
  90         assert(ctx != NULL);
  91
  92         now = time(NULL);
  93         if ((now - ctx->last) < SLEEP)
  94                 goto exit;
  95         ctx->last = now;
  96
  97         if (ctx->conn == NULL) {
  98                 if ((ctx->conn = mpd_connection_new(NULL, 0, 0)) == NULL) {
  99                         warnx("mpd_connection_new");
 100                         strncpy(ctx->mpd_str, NOTAVAILABLE, sizeof(ctx->mpd_str) - 1);
 101                         ctx->mpd_str[sizeof(ctx->mpd_str) - 1] = '\0';
 102                         goto exit;
 103                 }
 104         }
 105         assert(ctx->conn != NULL);
 106
 107         if ((status = mpd_run_status(ctx->conn)) == NULL) {
 108                 warnx("mpd_run_status: %s", mpd_connection_get_error_message(ctx->conn));
 109                 strncpy(ctx->mpd_str, NOTAVAILABLE, sizeof(ctx->mpd_str) - 1);
 110                 ctx->mpd_str[sizeof(ctx->mpd_str) - 1] = '\0';
 111
 112                 mpd_connection_free(ctx->conn);
 113                 ctx->conn = NULL;
 114                 goto exit;
 115         }
 116         if (mpd_status_get_state(status) != MPD_STATE_PLAY) {
 117                 ctx->mpd_str[0] = '\0';
 118                 goto exit;
 119         }
 120         if ((song = mpd_run_current_song(ctx->conn)) == NULL) {
 121                 strncpy(ctx->mpd_str, NOTAVAILABLE, sizeof(ctx->mpd_str) - 1);
 122                 ctx->mpd_str[sizeof(ctx->mpd_str) - 1] = '\0';
 123                 goto exit;
 124         }
 125         if ((artist = mpd_song_get_tag(song, MPD_TAG_ARTIST, 0)) == NULL)
 126                 artist = NOARTIST;
 127
 128         if ((title = mpd_song_get_tag(song, MPD_TAG_TITLE, 0)) == NULL)
 129                 title = NOTITLE;
 130
 131         inleft = tools_catitems(ctx->mpd_utf, sizeof(ctx->mpd_utf), artist, " - ", title, NULL);
 132
 133         inleft = inleft < sizeof(ctx->mpd_utf) ? inleft : (sizeof(ctx->mpd_utf) - 1);
 134         outleft = sizeof(ctx->mpd_str);
 135         in = (char *)ctx->mpd_utf;
 136         out = (char *)ctx->mpd_str;
 137
 138         if (iconv(ctx->cd, NULL, NULL, &out, &outleft) == (size_t) (-1))
 139                 err(EX_SOFTWARE, "iconv");
 140         while (inleft > 0) {
 141                 if (iconv(ctx->cd, (const char **)&in, &inleft, &out, &outleft) == (size_t) (-1)) {
 142                         if (errno == E2BIG)
 143                                 break;
 144                 }
 145         }
 146         *out = '\0';
 147
 148 exit:
 149         if (song != NULL)
 150                 mpd_song_free(song);
 151         if (status != NULL)
 152                 mpd_status_free(status);
 153
 154         return (ctx->mpd_str);
 155 }