mdw@git.distorted.org.uk Git - disorder/blob - server/rescan.c

   1 /*
   2  * This file is part of DisOrder
   3  * Copyright (C) 2005, 2006 Richard Kettlewell
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  18  * USA
  19  */
  20
  21 #include <config.h>
  22 #include "types.h"
  23
  24 #include <getopt.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <db.h>
  28 #include <locale.h>
  29 #include <errno.h>
  30 #include <sys/types.h>
  31 #include <unistd.h>
  32 #include <pcre.h>
  33 #include <fnmatch.h>
  34 #include <sys/wait.h>
  35 #include <string.h>
  36 #include <syslog.h>
  37
  38 #include "configuration.h"
  39 #include "syscalls.h"
  40 #include "log.h"
  41 #include "defs.h"
  42 #include "mem.h"
  43 #include "plugin.h"
  44 #include "inputline.h"
  45 #include "charset.h"
  46 #include "wstat.h"
  47 #include "kvp.h"
  48 #include "printf.h"
  49 #include "trackdb.h"
  50 #include "trackdb-int.h"
  51
  52 static DB_TXN *global_tid;
  53
  54 static const struct option options[] = {
  55   { "help", no_argument, 0, 'h' },
  56   { "version", no_argument, 0, 'V' },
  57   { "config", required_argument, 0, 'c' },
  58   { "debug", no_argument, 0, 'd' },
  59   { "no-debug", no_argument, 0, 'D' },
  60   { 0, 0, 0, 0 }
  61 };
  62
  63 /* display usage message and terminate */
  64 static void help(void) {
  65   xprintf("Usage:\n"
  66           "  disorder-rescan [OPTIONS] [PATH...]\n"
  67           "Options:\n"
  68           "  --help, -h              Display usage message\n"
  69           "  --version, -V           Display version number\n"
  70           "  --config PATH, -c PATH  Set configuration file\n"
  71           "  --debug, -d             Turn on debugging\n"
  72           "\n"
  73           "Rescanner for DisOrder.  Not intended to be run\n"
  74           "directly.\n");
  75   xfclose(stdout);
  76   exit(0);
  77 }
  78
  79 /* display version number and terminate */
  80 static void version(void) {
  81   xprintf("disorder-rescan version %s\n", disorder_version_string);
  82   xfclose(stdout);
  83   exit(0);
  84 }
  85
  86 static volatile sig_atomic_t signalled;
  87
  88 static void signal_handler(int sig) {
  89   if(sig == 0) _exit(-1);               /* "Cannot happen" */
  90   signalled = sig;
  91 }
  92
  93 static int aborted(void) {
  94   return signalled || getppid() == 1;
  95 }
  96
  97 /* Exit if our parent has gone away or we have been told to stop. */
  98 static void checkabort(void) {
  99   if(getppid() == 1) {
 100     info("parent has terminated");
 101     trackdb_abort_transaction(global_tid);
 102     exit(0);
 103   }
 104   if(signalled) {
 105     info("received signal %d", signalled);
 106     trackdb_abort_transaction(global_tid);
 107     exit(0);
 108   }
 109 }
 110
 111 /* rescan a collection */
 112 static void rescan_collection(const struct collection *c) {
 113   pid_t pid, r;
 114   int p[2], n, w;
 115   FILE *fp = 0;
 116   char *path, *track;
 117   long ntracks = 0, nnew = 0;
 118
 119   checkabort();
 120   info("rescanning %s with %s", c->root, c->module);
 121   /* plugin runs in a subprocess */
 122   xpipe(p);
 123   if(!(pid = xfork())) {
 124     exitfn = _exit;
 125     xclose(p[0]);
 126     xdup2(p[1], 1);
 127     xclose(p[1]);
 128     scan(c->module, c->root);
 129     if(fflush(stdout) < 0)
 130       fatal(errno, "error writing to scanner pipe");
 131     _exit(0);
 132   }
 133   xclose(p[1]);
 134   if(!(fp = fdopen(p[0], "r")))
 135     fatal(errno, "error calling fdopen");
 136   /* read tracks from the plugin */
 137   while(!inputline("rescanner", fp, &path, 0)) {
 138     checkabort();
 139     /* actually we can cope relatively well within the server, but they'll go
 140      * wrong in track listings */
 141     if(strchr(path, '\n')) {
 142       error(0, "cannot cope with tracks with newlines in the name");
 143       continue;
 144     }
 145     if(!(track = any2utf8(c->encoding, path))) {
 146       error(0, "cannot convert track path to UTF-8: %s", path);
 147       continue;
 148     }
 149     D(("track %s", track));
 150     /* only tracks with a known player are admitted */
 151     for(n = 0; (n < config->player.n
 152                 && fnmatch(config->player.s[n].s[0], track, 0) != 0); ++n)
 153       ;
 154     if(n < config->player.n) {
 155       nnew += !!trackdb_notice(track, path);
 156       ++ntracks;
 157     }
 158   }
 159   /* tidy up */
 160   if(ferror(fp)) {
 161     error(errno, "error reading from scanner pipe");
 162     goto done;
 163   }
 164   xfclose(fp);
 165   fp = 0;
 166   while((r = waitpid(pid, &w, 0)) == -1 && errno == EINTR)
 167     ;
 168   if(r < 0) fatal(errno, "error calling waitpid");
 169   pid = 0;
 170   if(w) {
 171     error(0, "scanner subprocess: %s", wstat(w));
 172     goto done;
 173   }
 174   info("rescanned %s, %ld tracks, %ld new", c->root, ntracks, nnew);
 175 done:
 176   if(fp)
 177     xfclose(fp);
 178   if(pid)
 179     while((r = waitpid(pid, &w, 0)) == -1 && errno == EINTR)
 180       ;
 181 }
 182
 183 struct recheck_state {
 184   const struct collection *c;
 185   long nobsolete, nlength;
 186 };
 187
 188 /* called for each non-alias track */
 189 static int recheck_callback(const char *track,
 190                             struct kvp *data,
 191                             void *u,
 192                             DB_TXN *tid) {
 193   struct recheck_state *cs = u;
 194   const struct collection *c = cs->c;
 195   const char *path = kvp_get(data, "_path");
 196   char buffer[20];
 197   int err;
 198   long n;
 199
 200   if(aborted()) return EINTR;
 201   D(("rechecking %s", track));
 202   /* see if the track has evaporated */
 203   if(check(c->module, c->root, path) == 0) {
 204     D(("obsoleting %s", track));
 205     if((err = trackdb_obsolete(track, tid))) return err;
 206     ++cs->nobsolete;
 207     return 0;
 208   }
 209   /* make sure we know the length */
 210   if(!kvp_get(data, "_length")) {
 211     D(("recalculating length of %s", track));
 212     n = tracklength(track, path);
 213     if(n > 0) {
 214       byte_snprintf(buffer, sizeof buffer, "%ld", n);
 215       kvp_set(&data, "_length", buffer);
 216       if((err = trackdb_putdata(trackdb_tracksdb, track, data, tid, 0)))
 217         return err;
 218       ++cs->nlength;
 219     }
 220   }
 221   return 0;
 222 }
 223
 224 /* recheck a collection */
 225 static void recheck_collection(const struct collection *c) {
 226   struct recheck_state cs;
 227
 228   info("rechecking %s", c->root);
 229   for(;;) {
 230     checkabort();
 231     global_tid = trackdb_begin_transaction();
 232     memset(&cs, 0, sizeof cs);
 233     cs.c = c;
 234     if(trackdb_scan(c->root, recheck_callback, &cs, global_tid)) goto fail;
 235     break;
 236   fail:
 237     /* Maybe we need to shut down */
 238     checkabort();
 239     /* Abort the transaction and try again in a bit. */
 240     trackdb_abort_transaction(global_tid);
 241     global_tid = 0;
 242     /* Let anything else that is going on get out of the way. */
 243     sleep(10);
 244     checkabort();
 245     info("resuming recheck of %s", c->root);
 246   }
 247   trackdb_commit_transaction(global_tid);
 248   global_tid = 0;
 249   info("rechecked %s, %ld obsoleted, %ld lengths calculated",
 250        c->root, cs.nobsolete, cs.nlength);
 251 }
 252
 253 /* rescan/recheck a collection by name */
 254 static void do_directory(const char *s,
 255                          void (*fn)(const struct collection *c)) {
 256   int n;
 257
 258   for(n = 0; (n < config->collection.n
 259               && strcmp(config->collection.s[n].root, s)); ++n)
 260     ;
 261   if(n < config->collection.n)
 262     fn(&config->collection.s[n]);
 263   else
 264     error(0, "no collection has root '%s'", s);
 265 }
 266
 267 /* rescan/recheck all collections */
 268 static void do_all(void (*fn)(const struct collection *c)) {
 269   int n;
 270
 271   for(n = 0; n < config->collection.n; ++n)
 272     fn(&config->collection.s[n]);
 273 }
 274
 275 int main(int argc, char **argv) {
 276   int n;
 277   struct sigaction sa;
 278
 279   set_progname(argv);
 280   mem_init(1);
 281   if(!setlocale(LC_CTYPE, "")) fatal(errno, "error calling setlocale");
 282   while((n = getopt_long(argc, argv, "hVc:dD", options, 0)) >= 0) {
 283     switch(n) {
 284     case 'h': help();
 285     case 'V': version();
 286     case 'c': configfile = optarg; break;
 287     case 'd': debugging = 1; break;
 288     case 'D': debugging = 0; break;
 289     default: fatal(0, "invalid option");
 290     }
 291   }
 292   /* If stderr is a TTY then log there, otherwise to syslog. */
 293   if(!isatty(2)) {
 294     openlog(progname, LOG_PID, LOG_DAEMON);
 295     log_default = &log_syslog;
 296   }
 297   if(config_read()) fatal(0, "cannot read configuration");
 298   xnice(config->nice_rescan);
 299   sa.sa_handler = signal_handler;
 300   sa.sa_flags = SA_RESTART;
 301   sigemptyset(&sa.sa_mask);
 302   xsigaction(SIGTERM, &sa, 0);
 303   xsigaction(SIGINT, &sa, 0);
 304   info("started");
 305   trackdb_init(0);
 306   trackdb_open();
 307   if(optind == argc) {
 308     do_all(rescan_collection);
 309     do_all(recheck_collection);
 310   }
 311   else {
 312     for(n = optind; n < argc; ++n)
 313       do_directory(argv[n], rescan_collection);
 314     for(n = optind; n < argc; ++n)
 315       do_directory(argv[n], recheck_collection);
 316   }
 317   trackdb_close();
 318   trackdb_deinit();
 319   info("completed");
 320   return 0;
 321 }
 322
 323 /*
 324 Local Variables:
 325 c-basic-offset:2
 326 comment-column:40
 327 fill-column:79
 328 indent-tabs-mode:nil
 329 End:
 330 */