diplodocus.org Git - nmh/blob - sbr/utils.c

   1 /* utils.c -- various utility routines
   2  *
   3  * This code is Copyright (c) 2006, by the authors of nmh.  See the
   4  * COPYRIGHT file in the root directory of the nmh distribution for
   5  * complete copyright information.
   6  */
   7
   8 #include <h/mh.h>
   9 #include <h/utils.h>
  10 #include <fcntl.h>
  11
  12 /* sbr/signals.c */
  13 extern int setup_signal_handlers();
  14
  15 /* sbr/m_mktemp.c */
  16 extern void remove_registered_files_atexit();
  17
  18 extern char *mhdocdir;
  19
  20 /* plurals gives the letter ess to indicate a plural noun, or an empty
  21  * string as plurals+1 for the singular noun.  Used by the PLURALS
  22  * macro. */
  23 const char plurals[] = "s";
  24
  25 /*
  26  * We allocate space for messages (msgs array)
  27  * this number of elements at a time.
  28  */
  29 #define MAXMSGS 256
  30
  31 /* Call malloc(3), exiting on NULL return. */
  32 void *mh_xmalloc(size_t size)
  33 {
  34     void *p;
  35
  36     if (size == 0)
  37         size = 1; /* Some mallocs don't like 0. */
  38     p = malloc(size);
  39     if (!p)
  40         adios(NULL, "malloc failed, size wanted: %zu", size);
  41
  42     return p;
  43 }
  44
  45 /* Call realloc(3), exiting on NULL return. */
  46 void *mh_xrealloc(void *ptr, size_t size)
  47 {
  48     void *new;
  49
  50     /* Copy POSIX behaviour, coping with non-POSIX systems. */
  51     if (size == 0) {
  52         mh_xfree(ptr);
  53         return mh_xmalloc(1); /* Get a unique pointer. */
  54     }
  55     if (!ptr)
  56         return mh_xmalloc(size);
  57
  58     new = realloc(ptr, size);
  59     if (!new)
  60         adios(NULL, "realloc failed, size wanted: %zu", size);
  61
  62     return new;
  63 }
  64
  65 /* Call calloc(3), exiting on NULL return. */
  66 void *mh_xcalloc(size_t nelem, size_t elsize)
  67 {
  68     void *p;
  69
  70     if (!nelem || !elsize)
  71         return mh_xmalloc(1); /* Get a unique pointer. */
  72
  73     p = calloc(nelem, elsize);
  74     if (!p)
  75         adios(NULL, "calloc failed, size wanted: %zu * %zu", nelem, elsize);
  76
  77     return p;
  78 }
  79
  80 /* Duplicate a NUL-terminated string, exit on failure. */
  81 char *mh_xstrdup(const char *src)
  82 {
  83     size_t n;
  84     char *dest;
  85
  86     n = strlen(src) + 1; /* Ignore possibility of overflow. */
  87     dest = mh_xmalloc(n);
  88     memcpy(dest, src, n);
  89
  90     return dest;
  91 }
  92
  93 /* Call free(3), if ptr isn't NULL. */
  94 void mh_xfree(void *ptr)
  95 {
  96     if (ptr)
  97         free(ptr); /* Some very old platforms can't cope with NULL. */
  98 }
  99
 100 /*
 101  * Return the present working directory, if the current directory does not
 102  * exist, or is too long, make / the pwd.
 103  */
 104 char *
 105 pwd(void)
 106 {
 107     char *cp;
 108     static char curwd[PATH_MAX];
 109
 110     if (!getcwd (curwd, PATH_MAX)) {
 111         inform("unable to determine working directory, continuing...");
 112         if (!mypath || !*mypath
 113                 || (strcpy (curwd, mypath), chdir (curwd)) == -1) {
 114             strcpy (curwd, "/");
 115             if (chdir (curwd) < 0) {
 116                 advise (curwd, "chdir");
 117             }
 118         }
 119         return curwd;
 120     }
 121
 122     if ((cp = curwd + strlen (curwd) - 1) > curwd && *cp == '/')
 123         *cp = '\0';
 124
 125     return curwd;
 126 }
 127
 128 /*
 129  * add   -- If "s1" is NULL, this routine just creates a
 130  *       -- copy of "s2" into newly malloc'ed memory.
 131  *       --
 132  *       -- If "s1" is not NULL, then copy the concatenation
 133  *       -- of "s1" and "s2" (note the order) into newly
 134  *       -- malloc'ed memory.  Then free "s1".
 135  */
 136 char *
 137 add (const char *s2, char *s1)
 138 {
 139     char *cp;
 140     size_t len1 = 0, len2 = 0;
 141
 142     if (s1)
 143         len1 = strlen (s1);
 144     if (s2)
 145         len2 = strlen (s2);
 146
 147     cp = mh_xmalloc (len1 + len2 + 1);
 148
 149     /* Copy s1 and free it */
 150     if (s1) {
 151         memcpy (cp, s1, len1);
 152         free (s1);
 153     }
 154
 155     /* Copy s2 */
 156     if (s2)
 157         memcpy (cp + len1, s2, len2);
 158
 159     /* Now NULL terminate the string */
 160     cp[len1 + len2] = '\0';
 161
 162     return cp;
 163 }
 164
 165 /*
 166  * addlist
 167  *      Append an item to a comma separated list
 168  */
 169 char *
 170 addlist (char *list, const char *item)
 171 {
 172     if (list)
 173         list = add (", ", list);
 174
 175     return add (item, list);
 176 }
 177
 178 /*
 179  * folder_exists
 180  *      Check to see if a folder exists.
 181  */
 182 int folder_exists(const char *folder)
 183 {
 184     struct stat st;
 185
 186     return stat(folder, &st) != -1;
 187 }
 188
 189 /*
 190  * create_folder
 191  *      Check to see if a folder exists, if not, prompt the user to create
 192  *      it.
 193  */
 194 void create_folder(char *folder, int autocreate, void (*done_callback)(int))
 195 {
 196     struct stat st;
 197     extern int errno;
 198     char *cp;
 199
 200     if (stat (folder, &st) == -1) {
 201         if (errno != ENOENT)
 202             adios (folder, "error on folder");
 203         if (autocreate == 0) {
 204             /* ask before creating folder */
 205             cp = concat ("Create folder \"", folder, "\"? ", NULL);
 206             if (!read_yes_or_no_if_tty (cp))
 207                 done_callback (1);
 208             free (cp);
 209         } else if (autocreate == -1) {
 210             /* do not create, so exit */
 211             done_callback (1);
 212         }
 213         if (!makedir (folder))
 214             adios (NULL, "unable to create folder %s", folder);
 215     }
 216 }
 217
 218 /*
 219  * num_digits
 220  *      Return the number of digits in a nonnegative integer.
 221  */
 222 int
 223 num_digits (int n)
 224 {
 225     int ndigits = 0;
 226
 227     /* Sanity check */
 228     if (n < 0)
 229         adios (NULL, "oops, num_digits called with negative value");
 230
 231     if (n == 0)
 232         return 1;
 233
 234     while (n) {
 235         n /= 10;
 236         ndigits++;
 237     }
 238
 239     return ndigits;
 240 }
 241
 242 /*
 243  * Append a message arg to an array of them, resizing it if necessary.
 244  * Really a simple vector-of-(char *) maintenance routine.
 245  */
 246 void
 247 app_msgarg(struct msgs_array *msgs, char *cp)
 248 {
 249         if(msgs->size >= msgs->max) {
 250                 msgs->max += MAXMSGS;
 251                 msgs->msgs = mh_xrealloc(msgs->msgs,
 252                         msgs->max * sizeof(*msgs->msgs));
 253         }
 254         msgs->msgs[msgs->size++] = cp;
 255 }
 256
 257 /*
 258  * Append a message number to an array of them, resizing it if necessary.
 259  * Like app_msgarg, but with a vector-of-ints instead.
 260  */
 261
 262 void
 263 app_msgnum(struct msgnum_array *msgs, int msgnum)
 264 {
 265         if (msgs->size >= msgs->max) {
 266                 msgs->max += MAXMSGS;
 267                 msgs->msgnums = mh_xrealloc(msgs->msgnums,
 268                         msgs->max * sizeof(*msgs->msgnums));
 269         }
 270         msgs->msgnums[msgs->size++] = msgnum;
 271 }
 272
 273 /* Open a form or components file */
 274 int
 275 open_form(char **form, char *def)
 276 {
 277         int in;
 278         if (*form) {
 279                 if ((in = open (etcpath (*form), O_RDONLY)) == NOTOK)
 280                         adios (*form, "unable to open form file");
 281         } else {
 282                 if ((in = open (etcpath (def), O_RDONLY)) == NOTOK)
 283                         adios (def, "unable to open default components file");
 284                 *form = def;
 285         }
 286         return in;
 287 }
 288
 289
 290 /*
 291  * Finds first occurrence of str in buf.  buf is not a C string but a
 292  * byte array of length buflen.  str is a null-terminated C string.
 293  * find_str() does not modify buf but passes back a non-const char *
 294  * pointer so that the caller can modify it.
 295  */
 296 char *
 297 find_str (const char buf[], size_t buflen, const char *str) {
 298     const size_t len = strlen (str);
 299     size_t i;
 300
 301     for (i = 0; i + len <= buflen; ++i, ++buf) {
 302         if (! memcmp (buf, str, len)) return (char *) buf;
 303     }
 304
 305     return NULL;
 306 }
 307
 308
 309 /*
 310  * Finds last occurrence of str in buf.  buf is not a C string but a
 311  * byte array of length buflen.  str is a null-terminated C string.
 312  * find_str() does not modify buf but passes back a non-const char *
 313  * pointer so that the caller can modify it.
 314  */
 315 char *
 316 rfind_str (const char buf[], size_t buflen, const char *str) {
 317     const size_t len = strlen (str);
 318     size_t i;
 319
 320     for (i = 0, buf += buflen - len; i + len <= buflen; ++i, --buf) {
 321         if (! memcmp (buf, str, len)) return (char *) buf;
 322     }
 323
 324     return NULL;
 325 }
 326
 327
 328 /* POSIX doesn't have strcasestr() so emulate it. */
 329 char *
 330 nmh_strcasestr (const char *s1, const char *s2) {
 331     const size_t len = strlen (s2);
 332
 333     if (isupper ((unsigned char) s2[0])  ||  islower ((unsigned char)s2[0])) {
 334         char first[3];
 335         first[0] = (char) toupper ((unsigned char) s2[0]);
 336         first[1] = (char) tolower ((unsigned char) s2[0]);
 337         first[2] = '\0';
 338
 339         for (s1 = strpbrk (s1, first); s1; s1 = strpbrk (++s1, first)) {
 340             if (! strncasecmp (s1, s2, len)) return (char *) s1;
 341         }
 342     } else {
 343         for (s1 = strchr (s1, s2[0]); s1; s1 = strchr (++s1, s2[0])) {
 344             if (! strncasecmp (s1, s2, len)) return (char *) s1;
 345         }
 346     }
 347
 348     return NULL;
 349 }
 350
 351
 352 /* truncpy copies at most size - 1 chars from non-NULL src to non-NULL,
 353  * non-overlapping, dst, and ensures dst is NUL terminated.  If size is
 354  * zero then it aborts as dst cannot be NUL terminated.
 355  *
 356  * It's to be used when truncation is intended and correct, e.g.
 357  * reporting a possibly very long external string back to the user.  One
 358  * of its advantages over strncpy(3) is it doesn't pad in the common
 359  * case of no truncation. */
 360 void trunccpy(char *dst, const char *src, size_t size)
 361 {
 362     if (!size) {
 363         inform("trunccpy: zero-length destination: \"%.20s\"",
 364             src ? src : "null");
 365         abort();
 366     }
 367
 368     if (strnlen(src, size) < size) {
 369         strcpy(dst, src);
 370     } else {
 371         memcpy(dst, src, size - 1);
 372         dst[size - 1] = '\0';
 373     }
 374 }
 375
 376
 377 /* has_prefix returns true if non-NULL s starts with non-NULL prefix. */
 378 bool has_prefix(const char *s, const char *prefix)
 379 {
 380     while (*s && *s == *prefix) {
 381         s++;
 382         prefix++;
 383     }
 384
 385     return *prefix == '\0';
 386 }
 387
 388
 389 /* has_suffix returns true if non-NULL s ends with non-NULL suffix. */
 390 bool has_suffix(const char *s, const char *suffix)
 391 {
 392     size_t ls, lsuf;
 393
 394     ls = strlen(s);
 395     lsuf = strlen(suffix);
 396
 397     return lsuf <= ls && !strcmp(s + ls - lsuf, suffix);
 398 }
 399
 400
 401 /* has_suffix_c returns true if non-NULL string s ends with a c before the
 402  * terminating NUL. */
 403 bool has_suffix_c(const char *s, int c)
 404 {
 405     return *s && s[strlen(s) - 1] == c;
 406 }
 407
 408
 409 /* trim_suffix_c deletes c from the end of non-NULL string s if it's
 410  * present, shortening s by 1.  Only one instance of c is removed. */
 411 void trim_suffix_c(char *s, int c)
 412 {
 413     if (!*s)
 414         return;
 415
 416     s += strlen(s) - 1;
 417     if (*s == c)
 418         *s = '\0';
 419 }
 420
 421
 422 /* to_lower runs all of s through tolower(3). */
 423 void to_lower(char *s)
 424 {
 425     unsigned char *b;
 426
 427     for (b = (unsigned char *)s; (*b = tolower(*b)); b++)
 428         ;
 429 }
 430
 431
 432 /* to_upper runs all of s through toupper(3). */
 433 void to_upper(char *s)
 434 {
 435     unsigned char *b;
 436
 437     for (b = (unsigned char *)s; (*b = toupper(*b)); b++)
 438         ;
 439 }
 440
 441
 442 int
 443 nmh_init(const char *argv0, int read_context) {
 444     int status = OK;
 445     char *locale;
 446
 447     invo_name = r1bindex ((char *) argv0, '/');
 448
 449     if (setup_signal_handlers()) {
 450         admonish("sigaction", "unable to set up signal handlers");
 451     }
 452
 453     /* POSIX atexit() does not define any error conditions. */
 454     if (atexit(remove_registered_files_atexit)) {
 455         admonish("atexit", "unable to register atexit function");
 456     }
 457
 458     /* Read context, if supposed to. */
 459     if (read_context) {
 460         int allow_version_check = 1;
 461         int check_older_version = 0;
 462         char *cp;
 463
 464         context_read();
 465
 466         if (read_context != 1  ||
 467             ((cp = context_find ("Welcome")) && strcasecmp (cp, "disable") == 0)) {
 468             allow_version_check = 0;
 469         } else if ((cp = getenv ("MHCONTEXT")) != NULL && *cp != '\0') {
 470             /* Context file comes from $MHCONTEXT, so only print the message
 471                if the context file has an older version.  If it does, or if it
 472                doesn't have a version at all, update the version. */
 473             check_older_version = 1;
 474         }
 475
 476         /* Check to see if the user is running a different (or older, if
 477            specified) version of nmh than they had run before, and notify them
 478            if so.  But only if read_context was set to a value to enable. */
 479         if (allow_version_check  &&  isatty (fileno (stdin))  &&
 480             isatty (fileno (stdout))  &&  isatty (fileno (stderr))) {
 481             if (nmh_version_changed (check_older_version)) {
 482                 printf ("==================================================="
 483                         "=====================\n");
 484                 printf ("Welcome to nmh version %s\n\n", VERSION);
 485                 printf ("See the release notes in %s/NEWS\n\n",
 486                          mhdocdir);
 487                 print_intro (stdout, 1);
 488                 printf ("\nThis message will not be repeated until "
 489                         "nmh is next updated.\n");
 490                 printf ("==================================================="
 491                         "=====================\n\n");
 492
 493                 fputs ("Press enter to continue: ", stdout);
 494                 (void) read_line ();
 495                 putchar ('\n');
 496             }
 497         }
 498     } else {
 499         if ((status = context_foil(NULL)) != OK) {
 500             advise("", "failed to create minimal profile/context");
 501         }
 502     }
 503
 504     /* Allow the user to set a locale in their profile.  Otherwise, use the
 505        "" string to pull it from their environment, see setlocale(3). */
 506     if ((locale = context_find ("locale")) == NULL) {
 507         locale = "";
 508     }
 509
 510     if (! setlocale (LC_ALL, locale)) {
 511         inform("setlocale failed, check your LC_ALL, LC_CTYPE, and LANG "
 512             "environment variables, continuing...");
 513     }
 514
 515     return status;
 516 }
 517
 518
 519 /*
 520  * Check stored version, and return 1 if out-of-date or non-existent.
 521  * Because the output of "mhparam version" is prefixed with "nmh-",
 522  * use that prefix here.
 523  */
 524 int
 525 nmh_version_changed (int older) {
 526     const char *const context_version = context_find("Version");
 527
 528     if (older) {
 529         /* Convert the version strings to floats and compare them.  This will
 530            break for versions with multiple decimal points, etc. */
 531         const float current_version = strtof (VERSION, NULL);
 532         const float old_version =
 533             context_version  &&  has_prefix(context_version, "nmh-")
 534             ?  strtof (context_version + 4, NULL)
 535             :  99999999;
 536
 537         if (context_version == NULL  ||  old_version < current_version) {
 538             context_replace ("Version", "nmh-" VERSION);
 539         }
 540
 541         return old_version < current_version;
 542     }
 543
 544     if (context_version == NULL  ||  strcmp(context_version, "nmh-" VERSION) != 0) {
 545         context_replace ("Version", "nmh-" VERSION);
 546         return 1;
 547     }
 548
 549     return 0;
 550 }
 551
 552
 553 /* Returns copy of argument str with all characters converted to upper
 554    case, and trimmed whitespace (see cpytrim()) . */
 555 char *
 556 upcase (const char *str) {
 557     char *up = cpytrim (str);
 558
 559     to_upper(up);
 560
 561     return up;
 562 }
 563
 564
 565 /*
 566  * Scan for any 8-bit characters.  Return 1 if they exist.
 567  *
 568  * Scan up until the given endpoint (but not the actual endpoint itself).
 569  * If the endpoint is NULL, scan until a '\0' is reached.
 570  */
 571
 572 int
 573 contains8bit(const char *start, const char *end)
 574 {
 575     if (! start)
 576         return 0;
 577
 578     while (*start != '\0' && (!end || (start < end)))
 579         if (! isascii((unsigned char) *start++))
 580             return 1;
 581
 582     return 0;
 583 }
 584
 585
 586 /*
 587  * See if input has any 8-bit bytes.
 588  */
 589 int
 590 scan_input (int fd, int *eightbit) {
 591     int state;
 592     char buf[BUFSIZ];
 593
 594     *eightbit = 0;
 595     lseek (fd, (off_t) 0, SEEK_SET);
 596
 597     while ((state = read (fd, buf, sizeof buf)) > 0) {
 598         if (contains8bit (buf, buf + state)) {
 599             *eightbit = 1;
 600             return OK;
 601         }
 602     }
 603
 604     return state == NOTOK  ?  NOTOK  :  OK;
 605 }