diplodocus.org Git - nmh/blob - uip/mhcachesbr.c

   1
   2 /*
   3  * mhcachesbr.c -- routines to manipulate the MIME content cache
   4  *
   5  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   6  * COPYRIGHT file in the root directory of the nmh distribution for
   7  * complete copyright information.
   8  */
   9
  10 #include <h/mh.h>
  11 #include <fcntl.h>
  12 #include <h/signals.h>
  13 #include <h/md5.h>
  14 #include <errno.h>
  15 #include <signal.h>
  16 #include <h/mts.h>
  17 #include <h/tws.h>
  18 #include <h/mime.h>
  19 #include <h/mhparse.h>
  20 #include <h/mhcachesbr.h>
  21 #include <h/utils.h>
  22
  23 #ifdef HAVE_SYS_TIME_H
  24 # include <sys/time.h>
  25 #endif
  26 #include <time.h>
  27
  28 extern int debugsw;
  29
  30 extern pid_t xpid;      /* mhshowsbr.c or mhbuildsbr.c */
  31
  32 /* cache policies */
  33 int rcachesw = CACHE_ASK;
  34 int wcachesw = CACHE_ASK;
  35
  36 /*
  37  * Location of public and private cache.  These must
  38  * be set before these routines are called.
  39  */
  40 char *cache_public;
  41 char *cache_private;
  42
  43
  44 /* mhmisc.c */
  45 int part_ok (CT, int);
  46 int type_ok (CT, int);
  47 void content_error (char *, CT, char *, ...);
  48 void flush_errors (void);
  49
  50 /*
  51  * prototypes
  52  */
  53 void cache_all_messages (CT *);
  54 int find_cache (CT, int, int *, char *, char *, int);
  55
  56 /*
  57  * static prototypes
  58  */
  59 static void cache_content (CT);
  60 static int find_cache_aux (int, char *, char *, char *, int);
  61 static int find_cache_aux2 (char *, char *, char *, int);
  62
  63
  64 /*
  65  * Top level entry point to cache content
  66  * from a group of messages
  67  */
  68
  69 void
  70 cache_all_messages (CT *cts)
  71 {
  72     CT ct, *ctp;
  73
  74     for (ctp = cts; *ctp; ctp++) {
  75         ct = *ctp;
  76         if (type_ok (ct, 1)) {
  77             cache_content (ct);
  78             if (ct->c_fp) {
  79                 fclose (ct->c_fp);
  80                 ct->c_fp = NULL;
  81             }
  82             if (ct->c_ceclosefnx)
  83                 (*ct->c_ceclosefnx) (ct);
  84         }
  85     }
  86     flush_errors ();
  87 }
  88
  89
  90 /*
  91  * Entry point to cache content from external sources.
  92  */
  93
  94 static void
  95 cache_content (CT ct)
  96 {
  97     int cachetype;
  98     char *file, cachefile[BUFSIZ];
  99     CE ce = ct->c_cefile;
 100
 101     if (!ct->c_id) {
 102         advise (NULL, "no %s: field in %s", ID_FIELD, ct->c_file);
 103         return;
 104     }
 105
 106     if (!ce) {
 107         advise (NULL, "unable to decode %s", ct->c_file);
 108         return;
 109     }
 110
 111     if (find_cache (NULL, wcachesw != CACHE_NEVER ? wcachesw : CACHE_ASK,
 112                     &cachetype, ct->c_id, cachefile, sizeof(cachefile))
 113             == NOTOK) {
 114         advise (NULL, "unable to cache %s's contents", ct->c_file);
 115         return;
 116     }
 117     if (wcachesw != CACHE_NEVER && wcachesw != CACHE_ASK) {
 118         fflush (stdout);
 119         fprintf (stderr, "caching message %s as file %s\n", ct->c_file,
 120                  cachefile);
 121     }
 122
 123     if (ce->ce_file) {
 124         int mask = umask (cachetype ? ~m_gmprot () : 0222);
 125         FILE *fp;
 126
 127         if (debugsw)
 128             fprintf (stderr, "caching by copying %s...\n", ce->ce_file);
 129
 130         file = NULL;
 131         if ((*ct->c_ceopenfnx) (ct, &file) == NOTOK)
 132             goto reset_umask;
 133
 134         if ((fp = fopen (cachefile, "w"))) {
 135             int cc;
 136             char buffer[BUFSIZ];
 137             FILE *gp = ce->ce_fp;
 138
 139             fseek (gp, 0L, SEEK_SET);
 140
 141             while ((cc = fread (buffer, sizeof(*buffer), sizeof(buffer), gp))
 142                        > 0)
 143                 fwrite (buffer, sizeof(*buffer), cc, fp);
 144             fflush (fp);
 145
 146             if (ferror (gp)) {
 147                 admonish (ce->ce_file, "error reading");
 148                 unlink (cachefile);
 149             } else {
 150                 if (ferror (fp)) {
 151                     admonish (cachefile, "error writing");
 152                     unlink (cachefile);
 153                 }
 154             }
 155             fclose (fp);
 156         } else
 157             content_error (cachefile, ct, "unable to fopen for writing");
 158 reset_umask:
 159         umask (mask);
 160     } else {
 161         if (debugsw)
 162             fprintf (stderr, "in place caching...\n");
 163
 164         file = cachefile;
 165         if ((*ct->c_ceopenfnx) (ct, &file) != NOTOK)
 166             chmod (cachefile, cachetype ? m_gmprot () : 0444);
 167     }
 168 }
 169
 170
 171 int
 172 find_cache (CT ct, int policy, int *writing, char *id,
 173         char *buffer, int buflen)
 174 {
 175     int status = NOTOK;
 176
 177     if (id == NULL)
 178         return NOTOK;
 179     id = trimcpy (id);
 180
 181     if (debugsw)
 182         fprintf (stderr, "find_cache %s(%d) %s %s\n", caches[policy].sw,
 183                  policy, writing ? "writing" : "reading", id);
 184
 185     switch (policy) {
 186         case CACHE_NEVER:
 187         default:
 188             break;
 189
 190         case CACHE_ASK:
 191         case CACHE_PUBLIC:
 192             if (cache_private
 193                     && !writing
 194                     && find_cache_aux (writing ? 2 : 0, cache_private, id,
 195                                        buffer, buflen) == OK) {
 196                 if (access (buffer, R_OK) != NOTOK) {
 197 got_private:
 198                     if (writing)
 199                         *writing = 1;
 200 got_it:
 201                     status = OK;
 202                     break;
 203                 }
 204             }
 205             if (cache_public
 206                     && find_cache_aux (writing ? 1 : 0, cache_public, id,
 207                                        buffer, buflen) == OK) {
 208                 if (writing || access (buffer, R_OK) != NOTOK) {
 209                     if (writing)
 210                         *writing = 0;
 211                     goto got_it;
 212                 }
 213             }
 214             break;
 215
 216         case CACHE_PRIVATE:
 217             if (cache_private
 218                     && find_cache_aux (writing ? 2 : 0, cache_private, id,
 219                                        buffer, buflen) == OK) {
 220                 if (writing || access (buffer, R_OK) != NOTOK)
 221                     goto got_private;
 222             }
 223             break;
 224
 225     }
 226
 227     if (status == OK && policy == CACHE_ASK) {
 228         int len, buflen;
 229         char *bp, query[BUFSIZ];
 230
 231         if (xpid) {
 232             if (xpid < 0)
 233                 xpid = -xpid;
 234             pidcheck (pidwait (xpid, NOTOK));
 235             xpid = 0;
 236         }
 237
 238         /* Get buffer ready to go */
 239         bp = query;
 240         buflen = sizeof(query);
 241
 242         /* Now, construct query */
 243         if (writing) {
 244             snprintf (bp, buflen, "Make cached, publically-accessible copy");
 245         } else {
 246             struct stat st;
 247
 248             snprintf (bp, buflen, "Use cached copy");
 249             len = strlen (bp);
 250             bp += len;
 251             buflen -= len;
 252
 253             if (ct->c_partno) {
 254                 snprintf (bp, buflen, " of content %s", ct->c_partno);
 255                 len = strlen (bp);
 256                 bp += len;
 257                 buflen -= len;
 258             }
 259
 260             stat (buffer, &st);
 261             snprintf (bp, buflen, " (size %lu octets)",
 262                             (unsigned long) st.st_size);
 263         }
 264         len = strlen (bp);
 265         bp += len;
 266         buflen -= len;
 267
 268         snprintf (bp, buflen, "\n    in file %s? ", buffer);
 269
 270         /* Now, check answer */
 271         if (!getanswer (query))
 272             status = NOTOK;
 273     }
 274
 275     if (status == OK && writing) {
 276         if (*writing && strchr(buffer, '/'))
 277             make_intermediates (buffer);
 278         unlink (buffer);
 279     }
 280
 281     free (id);
 282     return status;
 283 }
 284
 285
 286 static int
 287 find_cache_aux (int writing, char *directory, char *id,
 288         char *buffer, int buflen)
 289 {
 290     int mask, usemap;
 291     char mapfile[BUFSIZ], mapname[BUFSIZ];
 292     FILE *fp;
 293     static int partno, pid;
 294     static time_t clock = 0;
 295
 296     usemap = 1;
 297
 298     if (debugsw)
 299         fprintf (stderr, "find_cache_aux %s usemap=%d\n", directory, usemap);
 300
 301     snprintf (mapfile, sizeof(mapfile), "%s/cache.map", directory);
 302     if (find_cache_aux2 (mapfile, id, mapname, sizeof(mapname)) == OK)
 303         goto done_map;
 304
 305     if (!writing) {
 306         if (usemap)
 307             return NOTOK;
 308
 309 use_raw:
 310         snprintf (buffer, buflen, "%s/%s", directory, id);
 311         return OK;
 312     }
 313
 314     if (!usemap && access (mapfile, W_OK) == NOTOK)
 315         goto use_raw;
 316
 317     if (clock != 0) {
 318         time_t now;
 319
 320         time (&now);
 321         if (now > clock)
 322             clock = 0;
 323     } else {
 324         pid = getpid ();
 325     }
 326
 327     if (clock == 0) {
 328         time (&clock);
 329         partno = 0;
 330     } else {
 331         if (partno > 0xff) {
 332             clock++;
 333             partno = 0;
 334         }
 335     }
 336
 337     snprintf (mapname, sizeof(mapname), "%08x%04x%02x",
 338                 (unsigned int) (clock & 0xffffffff),
 339                 (unsigned int) (pid & 0xffff),
 340                 (unsigned int) (partno++ & 0xff));
 341
 342     if (debugsw)
 343         fprintf (stderr, "creating mapping %s->%s\n", mapname, id);
 344
 345     make_intermediates (mapfile);
 346     mask = umask (writing == 2 ? 0077 : 0);
 347     if (!(fp = lkfopen (mapfile, "a")) && errno == ENOENT) {
 348         int fd;
 349
 350         if ((fd = creat (mapfile, 0666)) != NOTOK) {
 351             close (fd);
 352             fp = lkfopen (mapfile, "a");
 353         }
 354     }
 355     umask (mask);
 356     if (!fp)
 357         return NOTOK;
 358     fprintf (fp, "%s: %s\n", mapname, id);
 359     lkfclose (fp, mapfile);
 360
 361 done_map:
 362     if (*mapname == '/')
 363         strncpy (buffer, mapname, buflen);
 364     else
 365         snprintf (buffer, buflen, "%s/%s", directory, mapname);
 366     if (debugsw)
 367         fprintf (stderr, "use %s\n", buffer);
 368
 369     return OK;
 370 }
 371
 372
 373 static int
 374 find_cache_aux2 (char *mapfile, char *id, char *mapname, int namelen)
 375 {
 376     int state;
 377     char buf[BUFSIZ], name[NAMESZ];
 378     FILE *fp;
 379     m_getfld_state_t gstate = 0;
 380
 381     if (!(fp = lkfopen (mapfile, "r")))
 382         return NOTOK;
 383
 384     for (;;) {
 385         int result;
 386         char *cp, *dp;
 387         int bufsz = sizeof buf;
 388
 389         switch (state = m_getfld (&gstate, name, buf, &bufsz, fp)) {
 390             case FLD:
 391             case FLDPLUS:
 392                 strncpy (mapname, name, namelen);
 393                 if (state != FLDPLUS)
 394                     cp = buf;
 395                 else {
 396                     cp = add (buf, NULL);
 397                     while (state == FLDPLUS) {
 398                         bufsz = sizeof buf;
 399                         state = m_getfld (&gstate, name, buf, &bufsz, fp);
 400                         cp = add (buf, cp);
 401                     }
 402                 }
 403                 dp = trimcpy (cp);
 404                 if (cp != buf)
 405                     free (cp);
 406                 if (debugsw)
 407                     fprintf (stderr, "compare %s to %s <- %s\n", id, dp,
 408                              mapname);
 409                 result = strcmp (id, dp);
 410                 free (dp);
 411                 if (result == 0) {
 412                     lkfclose (fp, mapfile);
 413                     return OK;
 414                 }
 415                 continue;
 416
 417             case BODY:
 418             case FILEEOF:
 419             default:
 420                 break;
 421         }
 422         break;
 423     }
 424     m_getfld_state_destroy (&gstate);
 425
 426     lkfclose (fp, mapfile);
 427     return NOTOK;
 428 }