1 /* Functions from hack's utils library.
2 Copyright (C) 1989, 1990, 1991, 1998, 1999, 2003, 2008, 2009
3 Free Software Foundation, Inc.
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 3, or (at your option)
8 any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU 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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
18
19 #include "config.h"
20
21 #include <stdio.h>
22 #include <stdarg.h>
23 #include <errno.h>
24 #ifndef errno
25 extern int errno;
26 #endif
27
28 #ifdef HAVE_STRINGS_H
29 # include <strings.h>
30 #else
31 # include <string.h>
32 #endif /* HAVE_STRINGS_H */
33
34 #ifdef HAVE_STDLIB_H
35 # include <stdlib.h>
36 #endif /* HAVE_STDLIB_H */
37
38 #include <sys/types.h>
39 #include <sys/stat.h>
40 #include <unistd.h>
41 #include <limits.h>
42
43 #include "utils.h"
44 #include "pathmax.h"
45
46 const char *myname;
47
48 /* Store information about files opened with ck_fopen
49 so that error messages from ck_fread, ck_fwrite, etc. can print the
50 name of the file that had the error */
51
52 struct open_file
53 {
54 FILE *fp;
55 char *name;
56 struct open_file *link;
57 unsigned temp : 1;
58 };
59
60 static struct open_file *open_files = NULL;
61 static void do_ck_fclose P_((FILE *fp));
62
63 /* Print an error message and exit */
64
65 void
panic(const char * str,...)66 panic(const char *str, ...)
67 {
68 va_list ap;
69
70 fprintf(stderr, "%s: ", myname);
71 va_start(ap, str);
72 #ifndef HAVE_VPRINTF
73 # ifndef HAVE_DOPRNT
74 fputs(str, stderr); /* not great, but perhaps better than nothing... */
75 # else /* HAVE_DOPRNT */
76 _doprnt(str, &ap, stderr);
77 # endif /* HAVE_DOPRNT */
78 #else /* HAVE_VFPRINTF */
79 vfprintf(stderr, str, ap);
80 #endif /* HAVE_VFPRINTF */
81 va_end(ap);
82 putc('\n', stderr);
83
84 /* Unlink the temporary files. */
85 while (open_files)
86 {
87 if (open_files->temp)
88 {
89 fclose (open_files->fp);
90 errno = 0;
91 unlink (open_files->name);
92 if (errno != 0)
93 fprintf (stderr, _("cannot remove %s: %s"), open_files->name, strerror (errno));
94 }
95
96 open_files = open_files->link;
97 }
98
99 exit(4);
100 }
101
102
103 /* Internal routine to get a filename from open_files */
104 static const char *utils_fp_name P_((FILE *fp));
105 static const char *
utils_fp_name(fp)106 utils_fp_name(fp)
107 FILE *fp;
108 {
109 struct open_file *p;
110
111 for (p=open_files; p; p=p->link)
112 if (p->fp == fp)
113 return p->name;
114 if (fp == stdin)
115 return "stdin";
116 else if (fp == stdout)
117 return "stdout";
118 else if (fp == stderr)
119 return "stderr";
120
121 return "<unknown>";
122 }
123
124 static void
register_open_file(fp,name,temp)125 register_open_file (fp, name, temp)
126 FILE *fp;
127 const char *name;
128 int temp;
129 {
130 struct open_file *p;
131 for (p=open_files; p; p=p->link)
132 {
133 if (fp == p->fp)
134 {
135 FREE(p->name);
136 break;
137 }
138 }
139 if (!p)
140 {
141 p = MALLOC(1, struct open_file);
142 p->link = open_files;
143 open_files = p;
144 }
145 p->name = ck_strdup(name);
146 p->fp = fp;
147 p->temp = false;
148 }
149
150 /* Panic on failing fopen */
151 FILE *
ck_fopen(name,mode,fail)152 ck_fopen(name, mode, fail)
153 const char *name;
154 const char *mode;
155 int fail;
156 {
157 FILE *fp;
158
159 fp = fopen (name, mode);
160 if (!fp)
161 {
162 if (fail)
163 panic(_("couldn't open file %s: %s"), name, strerror(errno));
164
165 return NULL;
166 }
167
168 register_open_file (fp, name, false);
169 return fp;
170 }
171
172 /* Panic on failing fdopen */
173 FILE *
ck_fdopen(fd,name,mode,fail)174 ck_fdopen(fd, name, mode, fail)
175 int fd;
176 const char *name;
177 const char *mode;
178 int fail;
179 {
180 FILE *fp;
181
182 fp = fdopen (fd, mode);
183 if (!fp)
184 {
185 if (fail)
186 panic(_("couldn't attach to %s: %s"), name, strerror(errno));
187
188 return NULL;
189 }
190
191 register_open_file (fp, name, false);
192 return fp;
193 }
194
195 FILE *
ck_mkstemp(p_filename,tmpdir,base)196 ck_mkstemp (p_filename, tmpdir, base)
197 char **p_filename;
198 char *base, *tmpdir;
199 {
200 char *template;
201 FILE *fp;
202 int fd;
203 int save_umask;
204
205 if (tmpdir == NULL)
206 tmpdir = getenv("TMPDIR");
207 if (tmpdir == NULL)
208 {
209 tmpdir = getenv("TMP");
210 if (tmpdir == NULL)
211 #ifdef P_tmpdir
212 tmpdir = P_tmpdir;
213 #else
214 tmpdir = "/tmp";
215 #endif
216 }
217
218 template = xmalloc (strlen (tmpdir) + strlen (base) + 8);
219 sprintf (template, "%s/%sXXXXXX", tmpdir, base);
220
221 /* The ownership might change, so omit some permissions at first
222 so unauthorized users cannot nip in before the file is ready. */
223 save_umask = umask (0700);
224 fd = mkstemp (template);
225 umask (save_umask);
226 if (fd == -1)
227 panic(_("couldn't open temporary file %s: %s"), template, strerror(errno));
228
229 *p_filename = template;
230 fp = fdopen (fd, "w");
231 register_open_file (fp, template, true);
232 return fp;
233 }
234
235 /* Panic on failing fwrite */
236 void
ck_fwrite(ptr,size,nmemb,stream)237 ck_fwrite(ptr, size, nmemb, stream)
238 const VOID *ptr;
239 size_t size;
240 size_t nmemb;
241 FILE *stream;
242 {
243 clearerr(stream);
244 if (size && fwrite(ptr, size, nmemb, stream) != nmemb)
245 panic(ngettext("couldn't write %d item to %s: %s",
246 "couldn't write %d items to %s: %s", nmemb),
247 nmemb, utils_fp_name(stream), strerror(errno));
248 }
249
250 /* Panic on failing fread */
251 size_t
ck_fread(ptr,size,nmemb,stream)252 ck_fread(ptr, size, nmemb, stream)
253 VOID *ptr;
254 size_t size;
255 size_t nmemb;
256 FILE *stream;
257 {
258 clearerr(stream);
259 if (size && (nmemb=fread(ptr, size, nmemb, stream)) <= 0 && ferror(stream))
260 panic(_("read error on %s: %s"), utils_fp_name(stream), strerror(errno));
261
262 return nmemb;
263 }
264
265 size_t
ck_getline(text,buflen,stream)266 ck_getline(text, buflen, stream)
267 char **text;
268 size_t *buflen;
269 FILE *stream;
270 {
271 int result;
272 if (!ferror (stream))
273 result = getline (text, buflen, stream);
274
275 if (ferror (stream))
276 panic (_("read error on %s: %s"), utils_fp_name(stream), strerror(errno));
277
278 return result;
279 }
280
281 /* Panic on failing fflush */
282 void
ck_fflush(stream)283 ck_fflush(stream)
284 FILE *stream;
285 {
286 clearerr(stream);
287 if (fflush(stream) == EOF && errno != EBADF)
288 panic("couldn't flush %s: %s", utils_fp_name(stream), strerror(errno));
289 }
290
291 /* Panic on failing fclose */
292 void
ck_fclose(stream)293 ck_fclose(stream)
294 FILE *stream;
295 {
296 struct open_file r;
297 struct open_file *prev;
298 struct open_file *cur;
299
300 /* a NULL stream means to close all files */
301 r.link = open_files;
302 prev = &r;
303 while ( (cur = prev->link) )
304 {
305 if (!stream || stream == cur->fp)
306 {
307 do_ck_fclose (cur->fp);
308 prev->link = cur->link;
309 FREE(cur->name);
310 FREE(cur);
311 }
312 else
313 prev = cur;
314 }
315
316 open_files = r.link;
317
318 /* Also care about stdout, because if it is redirected the
319 last output operations might fail and it is important
320 to signal this as an error (perhaps to make). */
321 if (!stream)
322 {
323 do_ck_fclose (stdout);
324 do_ck_fclose (stderr);
325 }
326 }
327
328 /* Close a single file. */
329 void
do_ck_fclose(fp)330 do_ck_fclose(fp)
331 FILE *fp;
332 {
333 ck_fflush(fp);
334 clearerr(fp);
335
336 if (fclose(fp) == EOF)
337 panic("couldn't close %s: %s", utils_fp_name(fp), strerror(errno));
338 }
339
340
341 /* Follow symlink and panic if something fails. Return the ultimate
342 symlink target, stored in a temporary buffer that the caller should
343 not free. */
344 const char *
follow_symlink(const char * fname)345 follow_symlink(const char *fname)
346 {
347 #ifdef ENABLE_FOLLOW_SYMLINKS
348 static char *buf1, *buf2;
349 static int buf_size;
350
351 struct stat statbuf;
352 const char *buf = fname, *c;
353 int rc;
354
355 if (buf_size == 0)
356 {
357 buf1 = ck_malloc (PATH_MAX + 1);
358 buf2 = ck_malloc (PATH_MAX + 1);
359 buf_size = PATH_MAX + 1;
360 }
361
362 while ((rc = lstat (buf, &statbuf)) == 0
363 && (statbuf.st_mode & S_IFLNK) == S_IFLNK)
364 {
365 if (buf == buf2)
366 {
367 strcpy (buf1, buf2);
368 buf = buf1;
369 }
370
371 while ((rc = readlink (buf, buf2, buf_size)) == buf_size)
372 {
373 buf_size *= 2;
374 buf1 = ck_realloc (buf1, buf_size);
375 buf2 = ck_realloc (buf2, buf_size);
376 }
377 if (rc < 0)
378 panic (_("couldn't follow symlink %s: %s"), buf, strerror(errno));
379 else
380 buf2 [rc] = '\0';
381
382 if (buf2[0] != '/' && (c = strrchr (buf, '/')) != NULL)
383 {
384 /* Need to handle relative paths with care. Reallocate buf1 and
385 buf2 to be big enough. */
386 int len = c - buf + 1;
387 if (len + rc + 1 > buf_size)
388 {
389 buf_size = len + rc + 1;
390 buf1 = ck_realloc (buf1, buf_size);
391 buf2 = ck_realloc (buf2, buf_size);
392 }
393
394 /* Always store the new path in buf1. */
395 if (buf != buf1)
396 memcpy (buf1, buf, len);
397
398 /* Tack the relative symlink at the end of buf1. */
399 memcpy (buf1 + len, buf2, rc + 1);
400 buf = buf1;
401 }
402 else
403 {
404 /* Use buf2 as the buffer, it saves a strcpy if it is not pointing to
405 another link. It works for absolute symlinks, and as long as
406 symlinks do not leave the current directory. */
407 buf = buf2;
408 }
409 }
410
411 if (rc < 0)
412 panic (_("cannot stat %s: %s"), buf, strerror(errno));
413
414 return buf;
415 #else
416 return fname;
417 #endif /* ENABLE_FOLLOW_SYMLINKS */
418 }
419
420 /* Panic on failing rename */
421 void
ck_rename(from,to,unlink_if_fail)422 ck_rename (from, to, unlink_if_fail)
423 const char *from, *to;
424 const char *unlink_if_fail;
425 {
426 int rd = rename (from, to);
427 if (rd != -1)
428 return;
429
430 if (unlink_if_fail)
431 {
432 int save_errno = errno;
433 errno = 0;
434 unlink (unlink_if_fail);
435
436 /* Failure to remove the temporary file is more severe, so trigger it first. */
437 if (errno != 0)
438 panic (_("cannot remove %s: %s"), unlink_if_fail, strerror (errno));
439
440 errno = save_errno;
441 }
442
443 panic (_("cannot rename %s: %s"), from, strerror (errno));
444 }
445
446
447
448
449 /* Panic on failing malloc */
450 VOID *
ck_malloc(size)451 ck_malloc(size)
452 size_t size;
453 {
454 VOID *ret = calloc(1, size ? size : 1);
455 if (!ret)
456 panic("couldn't allocate memory");
457 return ret;
458 }
459
460 /* Panic on failing realloc */
461 VOID *
ck_realloc(ptr,size)462 ck_realloc(ptr, size)
463 VOID *ptr;
464 size_t size;
465 {
466 VOID *ret;
467
468 if (size == 0)
469 {
470 FREE(ptr);
471 return NULL;
472 }
473 if (!ptr)
474 return ck_malloc(size);
475 ret = realloc(ptr, size);
476 if (!ret)
477 panic("couldn't re-allocate memory");
478 return ret;
479 }
480
481 /* Return a malloc()'d copy of a string */
482 char *
ck_strdup(str)483 ck_strdup(str)
484 const char *str;
485 {
486 char *ret = MALLOC(strlen(str)+1, char);
487 return strcpy(ret, str);
488 }
489
490 /* Return a malloc()'d copy of a block of memory */
491 VOID *
ck_memdup(buf,len)492 ck_memdup(buf, len)
493 const VOID *buf;
494 size_t len;
495 {
496 VOID *ret = ck_malloc(len);
497 return memcpy(ret, buf, len);
498 }
499
500 /* Release a malloc'd block of memory */
501 void
ck_free(ptr)502 ck_free(ptr)
503 VOID *ptr;
504 {
505 if (ptr)
506 free(ptr);
507 }
508
509
510 /* Implement a variable sized buffer of `stuff'. We don't know what it is,
511 nor do we care, as long as it doesn't mind being aligned by malloc. */
512
513 struct buffer
514 {
515 size_t allocated;
516 size_t length;
517 char *b;
518 };
519
520 #define MIN_ALLOCATE 50
521
522 struct buffer *
init_buffer()523 init_buffer()
524 {
525 struct buffer *b = MALLOC(1, struct buffer);
526 b->b = MALLOC(MIN_ALLOCATE, char);
527 b->allocated = MIN_ALLOCATE;
528 b->length = 0;
529 return b;
530 }
531
532 char *
get_buffer(b)533 get_buffer(b)
534 struct buffer *b;
535 {
536 return b->b;
537 }
538
539 size_t
size_buffer(b)540 size_buffer(b)
541 struct buffer *b;
542 {
543 return b->length;
544 }
545
546 static void resize_buffer P_((struct buffer *b, size_t newlen));
547 static void
resize_buffer(b,newlen)548 resize_buffer(b, newlen)
549 struct buffer *b;
550 size_t newlen;
551 {
552 char *try = NULL;
553 size_t alen = b->allocated;
554
555 if (newlen <= alen)
556 return;
557 alen *= 2;
558 if (newlen < alen)
559 try = realloc(b->b, alen); /* Note: *not* the REALLOC() macro! */
560 if (!try)
561 {
562 alen = newlen;
563 try = REALLOC(b->b, alen, char);
564 }
565 b->allocated = alen;
566 b->b = try;
567 }
568
569 char *
add_buffer(b,p,n)570 add_buffer(b, p, n)
571 struct buffer *b;
572 const char *p;
573 size_t n;
574 {
575 char *result;
576 if (b->allocated - b->length < n)
577 resize_buffer(b, b->length+n);
578 result = memcpy(b->b + b->length, p, n);
579 b->length += n;
580 return result;
581 }
582
583 char *
add1_buffer(b,c)584 add1_buffer(b, c)
585 struct buffer *b;
586 int c;
587 {
588 /* This special case should be kept cheap;
589 * don't make it just a mere convenience
590 * wrapper for add_buffer() -- even "builtin"
591 * versions of memcpy(a, b, 1) can become
592 * expensive when called too often.
593 */
594 if (c != EOF)
595 {
596 char *result;
597 if (b->allocated - b->length < 1)
598 resize_buffer(b, b->length+1);
599 result = b->b + b->length++;
600 *result = c;
601 return result;
602 }
603
604 return NULL;
605 }
606
607 void
free_buffer(b)608 free_buffer(b)
609 struct buffer *b;
610 {
611 if (b)
612 FREE(b->b);
613 FREE(b);
614 }
615