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