| 1 | /* histfile.c - functions to manipulate the history file. */ |
| 2 | |
| 3 | /* Copyright (C) 1989-2010 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file contains the GNU History Library (History), a set of |
| 6 | routines for managing the text of previously typed lines. |
| 7 | |
| 8 | History is free software: you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation, either version 3 of the License, or |
| 11 | (at your option) any later version. |
| 12 | |
| 13 | History is distributed in the hope that it will be useful, |
| 14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | GNU General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with History. If not, see <http://www.gnu.org/licenses/>. |
| 20 | */ |
| 21 | |
| 22 | /* The goal is to make the implementation transparent, so that you |
| 23 | don't have to know what data types are used, just what functions |
| 24 | you can call. I think I have done that. */ |
| 25 | |
| 26 | #define READLINE_LIBRARY |
| 27 | |
| 28 | #if defined (__TANDEM) |
| 29 | # include <floss.h> |
| 30 | #endif |
| 31 | |
| 32 | #if defined (HAVE_CONFIG_H) |
| 33 | # include <config.h> |
| 34 | #endif |
| 35 | |
| 36 | #include <stdio.h> |
| 37 | |
| 38 | #include <sys/types.h> |
| 39 | #if ! defined (_MINIX) && defined (HAVE_SYS_FILE_H) |
| 40 | # include <sys/file.h> |
| 41 | #endif |
| 42 | #include "posixstat.h" |
| 43 | #include <fcntl.h> |
| 44 | |
| 45 | #if defined (HAVE_STDLIB_H) |
| 46 | # include <stdlib.h> |
| 47 | #else |
| 48 | # include "ansi_stdlib.h" |
| 49 | #endif /* HAVE_STDLIB_H */ |
| 50 | |
| 51 | #if defined (HAVE_UNISTD_H) |
| 52 | # include <unistd.h> |
| 53 | #endif |
| 54 | |
| 55 | #include <ctype.h> |
| 56 | |
| 57 | #if defined (__EMX__) |
| 58 | # undef HAVE_MMAP |
| 59 | #endif |
| 60 | |
| 61 | #ifdef HISTORY_USE_MMAP |
| 62 | # include <sys/mman.h> |
| 63 | |
| 64 | # ifdef MAP_FILE |
| 65 | # define MAP_RFLAGS (MAP_FILE|MAP_PRIVATE) |
| 66 | # define MAP_WFLAGS (MAP_FILE|MAP_SHARED) |
| 67 | # else |
| 68 | # define MAP_RFLAGS MAP_PRIVATE |
| 69 | # define MAP_WFLAGS MAP_SHARED |
| 70 | # endif |
| 71 | |
| 72 | # ifndef MAP_FAILED |
| 73 | # define MAP_FAILED ((void *)-1) |
| 74 | # endif |
| 75 | |
| 76 | #endif /* HISTORY_USE_MMAP */ |
| 77 | |
| 78 | /* If we're compiling for __EMX__ (OS/2) or __CYGWIN__ (cygwin32 environment |
| 79 | on win 95/98/nt), we want to open files with O_BINARY mode so that there |
| 80 | is no \n -> \r\n conversion performed. On other systems, we don't want to |
| 81 | mess around with O_BINARY at all, so we ensure that it's defined to 0. */ |
| 82 | #if defined (__EMX__) || defined (__CYGWIN__) |
| 83 | # ifndef O_BINARY |
| 84 | # define O_BINARY 0 |
| 85 | # endif |
| 86 | #else /* !__EMX__ && !__CYGWIN__ */ |
| 87 | # undef O_BINARY |
| 88 | # define O_BINARY 0 |
| 89 | #endif /* !__EMX__ && !__CYGWIN__ */ |
| 90 | |
| 91 | #include <errno.h> |
| 92 | #if !defined (errno) |
| 93 | extern int errno; |
| 94 | #endif /* !errno */ |
| 95 | |
| 96 | #include "history.h" |
| 97 | #include "histlib.h" |
| 98 | |
| 99 | #include "rlshell.h" |
| 100 | #include "xmalloc.h" |
| 101 | |
| 102 | /* If non-zero, we write timestamps to the history file in history_do_write() */ |
| 103 | int history_write_timestamps = 0; |
| 104 | |
| 105 | /* Does S look like the beginning of a history timestamp entry? Placeholder |
| 106 | for more extensive tests. */ |
| 107 | #define HIST_TIMESTAMP_START(s) (*(s) == history_comment_char && isdigit ((s)[1]) ) |
| 108 | |
| 109 | /* Return the string that should be used in the place of this |
| 110 | filename. This only matters when you don't specify the |
| 111 | filename to read_history (), or write_history (). */ |
| 112 | static char * |
| 113 | history_filename (filename) |
| 114 | const char *filename; |
| 115 | { |
| 116 | char *return_val; |
| 117 | const char *home; |
| 118 | int home_len; |
| 119 | |
| 120 | return_val = filename ? savestring (filename) : (char *)NULL; |
| 121 | |
| 122 | if (return_val) |
| 123 | return (return_val); |
| 124 | |
| 125 | home = sh_get_env_value ("HOME"); |
| 126 | #ifdef _WIN32 |
| 127 | if (!home) |
| 128 | home = sh_get_env_value ("APPDATA"); |
| 129 | #endif |
| 130 | |
| 131 | if (home == 0) |
| 132 | { |
| 133 | #if 0 |
| 134 | home = "."; |
| 135 | home_len = 1; |
| 136 | #else |
| 137 | return (NULL); |
| 138 | #endif |
| 139 | } |
| 140 | else |
| 141 | home_len = strlen (home); |
| 142 | |
| 143 | return_val = (char *)xmalloc (2 + home_len + 8); /* strlen(".history") == 8 */ |
| 144 | strcpy (return_val, home); |
| 145 | return_val[home_len] = '/'; |
| 146 | #if defined (__MSDOS__) |
| 147 | strcpy (return_val + home_len + 1, "_history"); |
| 148 | #else |
| 149 | strcpy (return_val + home_len + 1, ".history"); |
| 150 | #endif |
| 151 | |
| 152 | return (return_val); |
| 153 | } |
| 154 | |
| 155 | /* Add the contents of FILENAME to the history list, a line at a time. |
| 156 | If FILENAME is NULL, then read from ~/.history. Returns 0 if |
| 157 | successful, or errno if not. */ |
| 158 | int |
| 159 | read_history (filename) |
| 160 | const char *filename; |
| 161 | { |
| 162 | return (read_history_range (filename, 0, -1)); |
| 163 | } |
| 164 | |
| 165 | /* Read a range of lines from FILENAME, adding them to the history list. |
| 166 | Start reading at the FROM'th line and end at the TO'th. If FROM |
| 167 | is zero, start at the beginning. If TO is less than FROM, read |
| 168 | until the end of the file. If FILENAME is NULL, then read from |
| 169 | ~/.history. Returns 0 if successful, or errno if not. */ |
| 170 | int |
| 171 | read_history_range (filename, from, to) |
| 172 | const char *filename; |
| 173 | int from, to; |
| 174 | { |
| 175 | register char *line_start, *line_end, *p; |
| 176 | char *input, *buffer, *bufend, *last_ts; |
| 177 | int file, current_line, chars_read; |
| 178 | struct stat finfo; |
| 179 | size_t file_size; |
| 180 | #if defined (EFBIG) |
| 181 | int overflow_errno = EFBIG; |
| 182 | #elif defined (EOVERFLOW) |
| 183 | int overflow_errno = EOVERFLOW; |
| 184 | #else |
| 185 | int overflow_errno = EIO; |
| 186 | #endif |
| 187 | |
| 188 | buffer = last_ts = (char *)NULL; |
| 189 | input = history_filename (filename); |
| 190 | file = input ? open (input, O_RDONLY|O_BINARY, 0666) : -1; |
| 191 | |
| 192 | if ((file < 0) || (fstat (file, &finfo) == -1)) |
| 193 | goto error_and_exit; |
| 194 | |
| 195 | file_size = (size_t)finfo.st_size; |
| 196 | |
| 197 | /* check for overflow on very large files */ |
| 198 | if (file_size != finfo.st_size || file_size + 1 < file_size) |
| 199 | { |
| 200 | errno = overflow_errno; |
| 201 | goto error_and_exit; |
| 202 | } |
| 203 | |
| 204 | #ifdef HISTORY_USE_MMAP |
| 205 | /* We map read/write and private so we can change newlines to NULs without |
| 206 | affecting the underlying object. */ |
| 207 | buffer = (char *)mmap (0, file_size, PROT_READ|PROT_WRITE, MAP_RFLAGS, file, 0); |
| 208 | if ((void *)buffer == MAP_FAILED) |
| 209 | { |
| 210 | errno = overflow_errno; |
| 211 | goto error_and_exit; |
| 212 | } |
| 213 | chars_read = file_size; |
| 214 | #else |
| 215 | buffer = (char *)malloc (file_size + 1); |
| 216 | if (buffer == 0) |
| 217 | { |
| 218 | errno = overflow_errno; |
| 219 | goto error_and_exit; |
| 220 | } |
| 221 | |
| 222 | chars_read = read (file, buffer, file_size); |
| 223 | #endif |
| 224 | if (chars_read < 0) |
| 225 | { |
| 226 | error_and_exit: |
| 227 | if (errno != 0) |
| 228 | chars_read = errno; |
| 229 | else |
| 230 | chars_read = EIO; |
| 231 | if (file >= 0) |
| 232 | close (file); |
| 233 | |
| 234 | FREE (input); |
| 235 | #ifndef HISTORY_USE_MMAP |
| 236 | FREE (buffer); |
| 237 | #endif |
| 238 | |
| 239 | return (chars_read); |
| 240 | } |
| 241 | |
| 242 | close (file); |
| 243 | |
| 244 | /* Set TO to larger than end of file if negative. */ |
| 245 | if (to < 0) |
| 246 | to = chars_read; |
| 247 | |
| 248 | /* Start at beginning of file, work to end. */ |
| 249 | bufend = buffer + chars_read; |
| 250 | current_line = 0; |
| 251 | |
| 252 | /* Skip lines until we are at FROM. */ |
| 253 | for (line_start = line_end = buffer; line_end < bufend && current_line < from; line_end++) |
| 254 | if (*line_end == '\n') |
| 255 | { |
| 256 | p = line_end + 1; |
| 257 | /* If we see something we think is a timestamp, continue with this |
| 258 | line. We should check more extensively here... */ |
| 259 | if (HIST_TIMESTAMP_START(p) == 0) |
| 260 | current_line++; |
| 261 | line_start = p; |
| 262 | } |
| 263 | |
| 264 | /* If there are lines left to gobble, then gobble them now. */ |
| 265 | for (line_end = line_start; line_end < bufend; line_end++) |
| 266 | if (*line_end == '\n') |
| 267 | { |
| 268 | /* Change to allow Windows-like \r\n end of line delimiter. */ |
| 269 | if (line_end > line_start && line_end[-1] == '\r') |
| 270 | line_end[-1] = '\0'; |
| 271 | else |
| 272 | *line_end = '\0'; |
| 273 | |
| 274 | if (*line_start) |
| 275 | { |
| 276 | if (HIST_TIMESTAMP_START(line_start) == 0) |
| 277 | { |
| 278 | add_history (line_start); |
| 279 | if (last_ts) |
| 280 | { |
| 281 | add_history_time (last_ts); |
| 282 | last_ts = NULL; |
| 283 | } |
| 284 | } |
| 285 | else |
| 286 | { |
| 287 | last_ts = line_start; |
| 288 | current_line--; |
| 289 | } |
| 290 | } |
| 291 | |
| 292 | current_line++; |
| 293 | |
| 294 | if (current_line >= to) |
| 295 | break; |
| 296 | |
| 297 | line_start = line_end + 1; |
| 298 | } |
| 299 | |
| 300 | FREE (input); |
| 301 | #ifndef HISTORY_USE_MMAP |
| 302 | FREE (buffer); |
| 303 | #else |
| 304 | munmap (buffer, file_size); |
| 305 | #endif |
| 306 | |
| 307 | return (0); |
| 308 | } |
| 309 | |
| 310 | /* Truncate the history file FNAME, leaving only LINES trailing lines. |
| 311 | If FNAME is NULL, then use ~/.history. Returns 0 on success, errno |
| 312 | on failure. */ |
| 313 | int |
| 314 | history_truncate_file (fname, lines) |
| 315 | const char *fname; |
| 316 | int lines; |
| 317 | { |
| 318 | char *buffer, *filename, *bp, *bp1; /* bp1 == bp+1 */ |
| 319 | int file, chars_read, rv; |
| 320 | struct stat finfo; |
| 321 | size_t file_size; |
| 322 | |
| 323 | buffer = (char *)NULL; |
| 324 | filename = history_filename (fname); |
| 325 | file = filename ? open (filename, O_RDONLY|O_BINARY, 0666) : -1; |
| 326 | rv = 0; |
| 327 | |
| 328 | /* Don't try to truncate non-regular files. */ |
| 329 | if (file == -1 || fstat (file, &finfo) == -1) |
| 330 | { |
| 331 | rv = errno; |
| 332 | if (file != -1) |
| 333 | close (file); |
| 334 | goto truncate_exit; |
| 335 | } |
| 336 | |
| 337 | if (S_ISREG (finfo.st_mode) == 0) |
| 338 | { |
| 339 | close (file); |
| 340 | #ifdef EFTYPE |
| 341 | rv = EFTYPE; |
| 342 | #else |
| 343 | rv = EINVAL; |
| 344 | #endif |
| 345 | goto truncate_exit; |
| 346 | } |
| 347 | |
| 348 | file_size = (size_t)finfo.st_size; |
| 349 | |
| 350 | /* check for overflow on very large files */ |
| 351 | if (file_size != finfo.st_size || file_size + 1 < file_size) |
| 352 | { |
| 353 | close (file); |
| 354 | #if defined (EFBIG) |
| 355 | rv = errno = EFBIG; |
| 356 | #elif defined (EOVERFLOW) |
| 357 | rv = errno = EOVERFLOW; |
| 358 | #else |
| 359 | rv = errno = EINVAL; |
| 360 | #endif |
| 361 | goto truncate_exit; |
| 362 | } |
| 363 | |
| 364 | buffer = (char *)malloc (file_size + 1); |
| 365 | if (buffer == 0) |
| 366 | { |
| 367 | close (file); |
| 368 | goto truncate_exit; |
| 369 | } |
| 370 | |
| 371 | chars_read = read (file, buffer, file_size); |
| 372 | close (file); |
| 373 | |
| 374 | if (chars_read <= 0) |
| 375 | { |
| 376 | rv = (chars_read < 0) ? errno : 0; |
| 377 | goto truncate_exit; |
| 378 | } |
| 379 | |
| 380 | /* Count backwards from the end of buffer until we have passed |
| 381 | LINES lines. bp1 is set funny initially. But since bp[1] can't |
| 382 | be a comment character (since it's off the end) and *bp can't be |
| 383 | both a newline and the history comment character, it should be OK. */ |
| 384 | for (bp1 = bp = buffer + chars_read - 1; lines && bp > buffer; bp--) |
| 385 | { |
| 386 | if (*bp == '\n' && HIST_TIMESTAMP_START(bp1) == 0) |
| 387 | lines--; |
| 388 | bp1 = bp; |
| 389 | } |
| 390 | |
| 391 | /* If this is the first line, then the file contains exactly the |
| 392 | number of lines we want to truncate to, so we don't need to do |
| 393 | anything. It's the first line if we don't find a newline between |
| 394 | the current value of i and 0. Otherwise, write from the start of |
| 395 | this line until the end of the buffer. */ |
| 396 | for ( ; bp > buffer; bp--) |
| 397 | { |
| 398 | if (*bp == '\n' && HIST_TIMESTAMP_START(bp1) == 0) |
| 399 | { |
| 400 | bp++; |
| 401 | break; |
| 402 | } |
| 403 | bp1 = bp; |
| 404 | } |
| 405 | |
| 406 | /* Write only if there are more lines in the file than we want to |
| 407 | truncate to. */ |
| 408 | if (bp > buffer && ((file = open (filename, O_WRONLY|O_TRUNC|O_BINARY, 0600)) != -1)) |
| 409 | { |
| 410 | write (file, bp, chars_read - (bp - buffer)); |
| 411 | |
| 412 | #if defined (__BEOS__) |
| 413 | /* BeOS ignores O_TRUNC. */ |
| 414 | ftruncate (file, chars_read - (bp - buffer)); |
| 415 | #endif |
| 416 | |
| 417 | close (file); |
| 418 | } |
| 419 | |
| 420 | truncate_exit: |
| 421 | |
| 422 | FREE (buffer); |
| 423 | |
| 424 | xfree (filename); |
| 425 | return rv; |
| 426 | } |
| 427 | |
| 428 | /* Workhorse function for writing history. Writes NELEMENT entries |
| 429 | from the history list to FILENAME. OVERWRITE is non-zero if you |
| 430 | wish to replace FILENAME with the entries. */ |
| 431 | static int |
| 432 | history_do_write (filename, nelements, overwrite) |
| 433 | const char *filename; |
| 434 | int nelements, overwrite; |
| 435 | { |
| 436 | register int i; |
| 437 | char *output; |
| 438 | int file, mode, rv; |
| 439 | #ifdef HISTORY_USE_MMAP |
| 440 | size_t cursize; |
| 441 | |
| 442 | mode = overwrite ? O_RDWR|O_CREAT|O_TRUNC|O_BINARY : O_RDWR|O_APPEND|O_BINARY; |
| 443 | #else |
| 444 | mode = overwrite ? O_WRONLY|O_CREAT|O_TRUNC|O_BINARY : O_WRONLY|O_APPEND|O_BINARY; |
| 445 | #endif |
| 446 | output = history_filename (filename); |
| 447 | file = output ? open (output, mode, 0600) : -1; |
| 448 | rv = 0; |
| 449 | |
| 450 | if (file == -1) |
| 451 | { |
| 452 | FREE (output); |
| 453 | return (errno); |
| 454 | } |
| 455 | |
| 456 | #ifdef HISTORY_USE_MMAP |
| 457 | cursize = overwrite ? 0 : lseek (file, 0, SEEK_END); |
| 458 | #endif |
| 459 | |
| 460 | if (nelements > history_length) |
| 461 | nelements = history_length; |
| 462 | |
| 463 | /* Build a buffer of all the lines to write, and write them in one syscall. |
| 464 | Suggested by Peter Ho (peter@robosts.oxford.ac.uk). */ |
| 465 | { |
| 466 | HIST_ENTRY **the_history; /* local */ |
| 467 | register int j; |
| 468 | int buffer_size; |
| 469 | char *buffer; |
| 470 | |
| 471 | the_history = history_list (); |
| 472 | /* Calculate the total number of bytes to write. */ |
| 473 | for (buffer_size = 0, i = history_length - nelements; i < history_length; i++) |
| 474 | #if 0 |
| 475 | buffer_size += 2 + HISTENT_BYTES (the_history[i]); |
| 476 | #else |
| 477 | { |
| 478 | if (history_write_timestamps && the_history[i]->timestamp && the_history[i]->timestamp[0]) |
| 479 | buffer_size += strlen (the_history[i]->timestamp) + 1; |
| 480 | buffer_size += strlen (the_history[i]->line) + 1; |
| 481 | } |
| 482 | #endif |
| 483 | |
| 484 | /* Allocate the buffer, and fill it. */ |
| 485 | #ifdef HISTORY_USE_MMAP |
| 486 | if (ftruncate (file, buffer_size+cursize) == -1) |
| 487 | goto mmap_error; |
| 488 | buffer = (char *)mmap (0, buffer_size, PROT_READ|PROT_WRITE, MAP_WFLAGS, file, cursize); |
| 489 | if ((void *)buffer == MAP_FAILED) |
| 490 | { |
| 491 | mmap_error: |
| 492 | rv = errno; |
| 493 | FREE (output); |
| 494 | close (file); |
| 495 | return rv; |
| 496 | } |
| 497 | #else |
| 498 | buffer = (char *)malloc (buffer_size); |
| 499 | if (buffer == 0) |
| 500 | { |
| 501 | rv = errno; |
| 502 | FREE (output); |
| 503 | close (file); |
| 504 | return rv; |
| 505 | } |
| 506 | #endif |
| 507 | |
| 508 | for (j = 0, i = history_length - nelements; i < history_length; i++) |
| 509 | { |
| 510 | if (history_write_timestamps && the_history[i]->timestamp && the_history[i]->timestamp[0]) |
| 511 | { |
| 512 | strcpy (buffer + j, the_history[i]->timestamp); |
| 513 | j += strlen (the_history[i]->timestamp); |
| 514 | buffer[j++] = '\n'; |
| 515 | } |
| 516 | strcpy (buffer + j, the_history[i]->line); |
| 517 | j += strlen (the_history[i]->line); |
| 518 | buffer[j++] = '\n'; |
| 519 | } |
| 520 | |
| 521 | #ifdef HISTORY_USE_MMAP |
| 522 | if (msync (buffer, buffer_size, 0) != 0 || munmap (buffer, buffer_size) != 0) |
| 523 | rv = errno; |
| 524 | #else |
| 525 | if (write (file, buffer, buffer_size) < 0) |
| 526 | rv = errno; |
| 527 | xfree (buffer); |
| 528 | #endif |
| 529 | } |
| 530 | |
| 531 | close (file); |
| 532 | |
| 533 | FREE (output); |
| 534 | |
| 535 | return (rv); |
| 536 | } |
| 537 | |
| 538 | /* Append NELEMENT entries to FILENAME. The entries appended are from |
| 539 | the end of the list minus NELEMENTs up to the end of the list. */ |
| 540 | int |
| 541 | append_history (nelements, filename) |
| 542 | int nelements; |
| 543 | const char *filename; |
| 544 | { |
| 545 | return (history_do_write (filename, nelements, HISTORY_APPEND)); |
| 546 | } |
| 547 | |
| 548 | /* Overwrite FILENAME with the current history. If FILENAME is NULL, |
| 549 | then write the history list to ~/.history. Values returned |
| 550 | are as in read_history ().*/ |
| 551 | int |
| 552 | write_history (filename) |
| 553 | const char *filename; |
| 554 | { |
| 555 | return (history_do_write (filename, history_length, HISTORY_OVERWRITE)); |
| 556 | } |