lib/util/util_file.c

   1 /*
   2  * Unix SMB/CIFS implementation.
   3  * SMB parameters and setup
   4  * Copyright (C) Andrew Tridgell 1992-1998 Modified by Jeremy Allison 1995.
   5  *
   6  * Added afdgets() Jelmer Vernooij 2005
   7  *
   8  * This program is free software; you can redistribute it and/or modify it under
   9  * the terms of the GNU General Public License as published by the Free
  10  * Software Foundation; either version 3 of the License, or (at your option)
  11  * any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful, but WITHOUT
  14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  16  * more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along with
  19  * this program; if not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include "replace.h"
  23 #include "system/shmem.h"
  24 #include "system/filesys.h"
  25 #include <talloc.h>
  26 #include "lib/util/samba_util.h"
  27 #include "lib/util/sys_popen.h"
  28 #include "lib/util/sys_rw.h"
  29 #include "lib/util/debug.h"
  30
  31 /**
  32  * Read one line (data until next newline or eof) and allocate it
  33  */
  34 _PUBLIC_ char *afdgets(int fd, TALLOC_CTX *mem_ctx, size_t hint)
  35 {
  36         char *data = NULL;
  37         ssize_t alloc_size = 0, offset = 0, ret;
  38         int p;
  39
  40         if (hint <= 0) hint = 0x100;
  41
  42         do {
  43                 alloc_size += hint;
  44
  45                 data = talloc_realloc(mem_ctx, data, char, alloc_size);
  46
  47                 if (!data)
  48                         return NULL;
  49
  50                 ret = read(fd, data + offset, hint);
  51
  52                 if (ret == 0) {
  53                         return NULL;
  54                 }
  55
  56                 if (ret == -1) {
  57                         talloc_free(data);
  58                         return NULL;
  59                 }
  60
  61                 /* Find newline */
  62                 for (p = 0; p < ret; p++) {
  63                         if (data[offset + p] == '\n')
  64                                 break;
  65                 }
  66
  67                 if (p < ret) {
  68                         data[offset + p] = '\0';
  69
  70                         /* Go back to position of newline */
  71                         lseek(fd, p - ret + 1, SEEK_CUR);
  72                         return data;
  73                 }
  74
  75                 offset += ret;
  76
  77         } while ((size_t)ret == hint);
  78
  79         data[offset] = '\0';
  80
  81         return data;
  82 }
  83
  84 char *fgets_slash(TALLOC_CTX *mem_ctx, char *s2, size_t maxlen, FILE *f)
  85 {
  86         char *s = s2;
  87         size_t len = 0;
  88         int c;
  89         bool start_of_line = true;
  90
  91         if (feof(f)) {
  92                 return NULL;
  93         }
  94
  95         if (maxlen < 2) {
  96                 return NULL;
  97         }
  98
  99         if (s2 == NULL) {
 100                 maxlen = MIN(maxlen,8);
 101                 s = talloc_array(mem_ctx, char, maxlen);
 102         }
 103
 104         if (s == NULL) {
 105                 return NULL;
 106         }
 107
 108         *s = 0;
 109
 110         while (len < maxlen-1) {
 111                 c = getc(f);
 112                 switch (c)
 113                 {
 114                     case '\r':
 115                             break;
 116                     case '\n':
 117                             while (len > 0 && s[len-1] == ' ') {
 118                                     s[--len] = 0;
 119                             }
 120                             if (len > 0 && s[len-1] == '\\') {
 121                                     s[--len] = 0;
 122                                     start_of_line = true;
 123                                     break;
 124                             }
 125                             return s;
 126                     case EOF:
 127                             if (len <= 0 && (s2 == NULL)) {
 128                                     TALLOC_FREE(s);
 129                             }
 130                             return (len>0) ? s : NULL;
 131                     case ' ':
 132                             if (start_of_line) {
 133                                     break;
 134                             }
 135
 136                             FALL_THROUGH;
 137                     default:
 138                             start_of_line = false;
 139                             s[len++] = c;
 140                             s[len] = 0;
 141                 }
 142                 if ((s2 == NULL) && (len > maxlen-3)) {
 143                         size_t m;
 144                         char *t;
 145
 146                         m = maxlen * 2;
 147                         if (m < maxlen) {
 148                                 DBG_ERR("length overflow");
 149                                 TALLOC_FREE(s);
 150                                 return NULL;
 151                         }
 152                         maxlen = m;
 153
 154                         t = talloc_realloc(mem_ctx, s, char, maxlen);
 155                         if (t == NULL) {
 156                                 DBG_ERR("failed to expand buffer!\n");
 157                                 TALLOC_FREE(s);
 158                                 return NULL;
 159                         }
 160
 161                         s = t;
 162                 }
 163         }
 164
 165         return s;
 166 }
 167
 168 /**
 169 load a file into memory from a fd.
 170 **/
 171 _PUBLIC_ char *fd_load(int fd, size_t *psize, size_t maxsize, TALLOC_CTX *mem_ctx)
 172 {
 173         FILE *file;
 174         char *p = NULL;
 175         size_t size = 0;
 176         size_t chunk = 1024;
 177         int err;
 178
 179         if (maxsize == 0) {
 180                 maxsize = SIZE_MAX;
 181         }
 182
 183         file = fdopen(fd, "r");
 184         if (file == NULL) {
 185                 return NULL;
 186         }
 187
 188         while (size < maxsize) {
 189                 size_t newbufsize;
 190                 size_t nread;
 191
 192                 chunk = MIN(chunk, (maxsize - size));
 193
 194                 newbufsize = size + (chunk+1); /* chunk+1 can't overflow */
 195                 if (newbufsize < size) {
 196                         goto fail; /* overflow */
 197                 }
 198
 199                 p = talloc_realloc(mem_ctx, p, char, newbufsize);
 200                 if (p == NULL) {
 201                         goto fail;
 202                 }
 203
 204                 nread = fread(p+size, 1, chunk, file);
 205                 size += nread;
 206
 207                 if (nread != chunk) {
 208                         break;
 209                 }
 210         }
 211
 212         err = ferror(file);
 213         if (err != 0) {
 214                 goto fail;
 215         }
 216
 217         p[size] = '\0';
 218
 219         if (psize != NULL) {
 220                 *psize = size;
 221         }
 222
 223         fclose(file);
 224         return p;
 225
 226 fail:
 227         TALLOC_FREE(p);
 228         fclose(file);
 229         return NULL;
 230 }
 231
 232 /**
 233 load a file into memory
 234 **/
 235 _PUBLIC_ char *file_load(const char *fname, size_t *size, size_t maxsize, TALLOC_CTX *mem_ctx)
 236 {
 237         int fd;
 238         char *p;
 239
 240         if (!fname || !*fname) return NULL;
 241
 242         fd = open(fname,O_RDONLY);
 243         if (fd == -1) return NULL;
 244
 245         p = fd_load(fd, size, maxsize, mem_ctx);
 246
 247         close(fd);
 248
 249         return p;
 250 }
 251
 252 /**
 253 parse a buffer into lines
 254 'p' will be freed on error, and otherwise will be made a child of the returned array
 255 **/
 256 static char **file_lines_parse_internal(char *p, size_t size, int *numlines, TALLOC_CTX *mem_ctx)
 257 {
 258         unsigned int i;
 259         char *s, **ret;
 260
 261         if (!p) return NULL;
 262
 263         for (s = p, i=0; s < p+size; s++) {
 264                 if (s[0] == '\n') i++;
 265         }
 266
 267         ret = talloc_zero_array(mem_ctx, char *, i+2);
 268         if (!ret) {
 269                 talloc_free(p);
 270                 return NULL;
 271         }
 272
 273         talloc_steal(ret, p);
 274
 275         ret[0] = p;
 276         for (s = p, i=1; s < p+size; s++) {
 277                 if (s[0] == '\n') {
 278                         s[0] = 0;
 279                         ret[i] = s+1;
 280                         i++;
 281                 }
 282                 if (s[0] == '\r') s[0] = 0;
 283         }
 284
 285         /* remove any blank lines at the end */
 286         while (i > 0 && ret[i-1][0] == 0) {
 287                 i--;
 288         }
 289
 290         if (numlines) *numlines = i;
 291
 292         return ret;
 293 }
 294
 295
 296 /**
 297 load a file into memory and return an array of pointers to lines in the file
 298 must be freed with talloc_free().
 299 **/
 300 _PUBLIC_ char **file_lines_load(const char *fname, int *numlines, size_t maxsize, TALLOC_CTX *mem_ctx)
 301 {
 302         char *p;
 303         size_t size;
 304
 305         p = file_load(fname, &size, maxsize, mem_ctx);
 306         if (!p) return NULL;
 307
 308         return file_lines_parse_internal(p, size, numlines, mem_ctx);
 309 }
 310
 311 /**
 312 load a fd into memory and return an array of pointers to lines in the file
 313 must be freed with talloc_free(). If convert is true calls unix_to_dos on
 314 the list.
 315 **/
 316 _PUBLIC_ char **fd_lines_load(int fd, int *numlines, size_t maxsize, TALLOC_CTX *mem_ctx)
 317 {
 318         char *p;
 319         size_t size;
 320
 321         p = fd_load(fd, &size, maxsize, mem_ctx);
 322         if (!p) return NULL;
 323
 324         return file_lines_parse_internal(p, size, numlines, mem_ctx);
 325 }
 326
 327 _PUBLIC_ char **file_lines_parse(const char *p_in,
 328                         size_t size,
 329                         int *numlines,
 330                         TALLOC_CTX *mem_ctx)
 331 {
 332         /*
 333          * Copy the incoming string so it can end up
 334          * being owned by the returned pointer and
 335          * freed when that is.
 336          */
 337         char *p = talloc_strdup(mem_ctx, p_in);
 338         if (p == NULL) {
 339                 return NULL;
 340         }
 341         return file_lines_parse_internal(p, size, numlines, mem_ctx);
 342 }
 343
 344 _PUBLIC_ bool file_save_mode(const char *fname, const void *packet,
 345                              size_t length, mode_t mode)
 346 {
 347         ssize_t num_written;
 348         int fd;
 349         fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, mode);
 350         if (fd == -1) {
 351                 return false;
 352         }
 353         num_written = write(fd, packet, length);
 354         if (num_written == -1 || (size_t)num_written != length) {
 355                 close(fd);
 356                 return false;
 357         }
 358         close(fd);
 359         return true;
 360 }
 361
 362 /**
 363   save a lump of data into a file. Mostly used for debugging
 364 */
 365 _PUBLIC_ bool file_save(const char *fname, const void *packet, size_t length)
 366 {
 367         return file_save_mode(fname, packet, length, 0644);
 368 }
 369
 370 _PUBLIC_ int vfdprintf(int fd, const char *format, va_list ap)
 371 {
 372         char *p;
 373         int len, ret;
 374         va_list ap2;
 375
 376         va_copy(ap2, ap);
 377         len = vasprintf(&p, format, ap2);
 378         va_end(ap2);
 379         if (len <= 0) return len;
 380         ret = write(fd, p, len);
 381         SAFE_FREE(p);
 382         return ret;
 383 }
 384
 385 _PUBLIC_ int fdprintf(int fd, const char *format, ...)
 386 {
 387         va_list ap;
 388         int ret;
 389
 390         va_start(ap, format);
 391         ret = vfdprintf(fd, format, ap);
 392         va_end(ap);
 393         return ret;
 394 }
 395
 396
 397 /*
 398   compare two files, return true if the two files have the same content
 399  */
 400 bool file_compare(const char *path1, const char *path2)
 401 {
 402         FILE *f1 = NULL, *f2 = NULL;
 403         uint8_t buf1[1024], buf2[1024];
 404         bool ret = false;
 405
 406         f1 = fopen(path1, "r");
 407         if (f1 == NULL) {
 408                 goto done;
 409         }
 410         f2 = fopen(path2, "r");
 411         if (f2 == NULL) {
 412                 goto done;
 413         }
 414
 415         while (!feof(f1)) {
 416                 size_t n1 = fread(buf1, 1, sizeof(buf1), f1);
 417                 size_t n2 = fread(buf2, 1, sizeof(buf2), f2);
 418
 419                 if (n1 != n2) {
 420                         goto done;
 421                 }
 422                 if (n1 == 0) {
 423                         ret = (feof(f1) && feof(f2));
 424                         goto done;
 425                 }
 426                 if (memcmp(buf1, buf2, n1) != 0) {
 427                         goto done;
 428                 }
 429                 if (n1 < sizeof(buf1)) {
 430                         bool has_error = (ferror(f1) || ferror(f2));
 431                         if (has_error) {
 432                                 goto done;
 433                         }
 434                 }
 435         }
 436         ret = true;
 437 done:
 438         if (f2 != NULL) {
 439                 fclose(f2);
 440         }
 441         if (f1 != NULL) {
 442                 fclose(f1);
 443         }
 444         return ret;
 445 }
 446
 447 /**
 448  Load from a pipe into memory.
 449 **/
 450 char *file_ploadv(char * const argl[], size_t *size)
 451 {
 452         int fd, n;
 453         char *p = NULL;
 454         char buf[1024];
 455         size_t total;
 456
 457         fd = sys_popenv(argl);
 458         if (fd == -1) {
 459                 return NULL;
 460         }
 461
 462         total = 0;
 463
 464         while ((n = sys_read(fd, buf, sizeof(buf))) > 0) {
 465                 p = talloc_realloc(NULL, p, char, total + n + 1);
 466                 if (p == NULL) {
 467                         DBG_ERR("failed to expand buffer!\n");
 468                         close(fd);
 469                         return NULL;
 470                 }
 471                 memcpy(p+total, buf, n);
 472                 total += n;
 473         }
 474
 475         if (p != NULL) {
 476                 p[total] = 0;
 477         }
 478
 479         /*
 480          * FIXME: Perhaps ought to check that the command completed
 481          * successfully (returned 0); if not the data may be
 482          * truncated.
 483          */
 484         sys_pclose(fd);
 485
 486         if (size) {
 487                 *size = total;
 488         }
 489
 490         return p;
 491 }