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