1/* vi: set sw=4 ts=4: */ 2/* 3 * sed.c - very minimalist version of sed 4 * 5 * Copyright (C) 1999,2000,2001 by Lineo, inc. and Mark Whitley 6 * Copyright (C) 1999,2000,2001 by Mark Whitley <markw@codepoet.org> 7 * Copyright (C) 2002 Matt Kraai 8 * Copyright (C) 2003 by Glenn McGrath 9 * Copyright (C) 2003,2004 by Rob Landley <rob@landley.net> 10 * 11 * MAINTAINER: Rob Landley <rob@landley.net> 12 * 13 * Licensed under GPL version 2, see file LICENSE in this tarball for details. 14 */ 15 16/* Code overview. 17 18 Files are laid out to avoid unnecessary function declarations. So for 19 example, every function add_cmd calls occurs before add_cmd in this file. 20 21 add_cmd() is called on each line of sed command text (from a file or from 22 the command line). It calls get_address() and parse_cmd_args(). The 23 resulting sed_cmd_t structures are appended to a linked list 24 (G.sed_cmd_head/G.sed_cmd_tail). 25 26 add_input_file() adds a FILE* to the list of input files. We need to 27 know all input sources ahead of time to find the last line for the $ match. 28 29 process_files() does actual sedding, reading data lines from each input FILE * 30 (which could be stdin) and applying the sed command list (sed_cmd_head) to 31 each of the resulting lines. 32 33 sed_main() is where external code calls into this, with a command line. 34*/ 35 36 37/* 38 Supported features and commands in this version of sed: 39 40 - comments ('#') 41 - address matching: num|/matchstr/[,num|/matchstr/|$]command 42 - commands: (p)rint, (d)elete, (s)ubstitue (with g & I flags) 43 - edit commands: (a)ppend, (i)nsert, (c)hange 44 - file commands: (r)ead 45 - backreferences in substitution expressions (\0, \1, \2...\9) 46 - grouped commands: {cmd1;cmd2} 47 - transliteration (y/source-chars/dest-chars/) 48 - pattern space hold space storing / swapping (g, h, x) 49 - labels / branching (: label, b, t, T) 50 51 (Note: Specifying an address (range) to match is *optional*; commands 52 default to the whole pattern space if no specific address match was 53 requested.) 54 55 Todo: 56 - Create a wrapper around regex to make libc's regex conform with sed 57 58 Reference http://www.opengroup.org/onlinepubs/007904975/utilities/sed.html 59*/ 60 61#include "libbb.h" 62#include "xregex.h" 63 64enum { 65 OPT_in_place = 1 << 0, 66}; 67 68/* Each sed command turns into one of these structures. */ 69typedef struct sed_cmd_s { 70 /* Ordered by alignment requirements: currently 36 bytes on x86 */ 71 struct sed_cmd_s *next; /* Next command (linked list, NULL terminated) */ 72 73 /* address storage */ 74 regex_t *beg_match; /* sed -e '/match/cmd' */ 75 regex_t *end_match; /* sed -e '/match/,/end_match/cmd' */ 76 regex_t *sub_match; /* For 's/sub_match/string/' */ 77 int beg_line; /* 'sed 1p' 0 == apply commands to all lines */ 78 int end_line; /* 'sed 1,3p' 0 == one line only. -1 = last line ($) */ 79 80 FILE *sw_file; /* File (sw) command writes to, -1 for none. */ 81 char *string; /* Data string for (saicytb) commands. */ 82 83 unsigned which_match; /* (s) Which match to replace (0 for all) */ 84 85 /* Bitfields (gcc won't group them if we don't) */ 86 unsigned invert:1; /* the '!' after the address */ 87 unsigned in_match:1; /* Next line also included in match? */ 88 unsigned sub_p:1; /* (s) print option */ 89 90 char sw_last_char; /* Last line written by (sw) had no '\n' */ 91 92 /* GENERAL FIELDS */ 93 char cmd; /* The command char: abcdDgGhHilnNpPqrstwxy:={} */ 94} sed_cmd_t; 95 96static const char semicolon_whitespace[] ALIGN1 = "; \n\r\t\v"; 97 98struct globals { 99 /* options */ 100 int be_quiet, regex_type; 101 FILE *nonstdout; 102 char *outname, *hold_space; 103 104 /* List of input files */ 105 int input_file_count, current_input_file; 106 FILE **input_file_list; 107 108 regmatch_t regmatch[10]; 109 regex_t *previous_regex_ptr; 110 111 /* linked list of sed commands */ 112 sed_cmd_t sed_cmd_head, *sed_cmd_tail; 113 114 /* Linked list of append lines */ 115 llist_t *append_head; 116 117 char *add_cmd_line; 118 119 struct pipeline { 120 char *buf; /* Space to hold string */ 121 int idx; /* Space used */ 122 int len; /* Space allocated */ 123 } pipeline; 124} FIX_ALIASING; 125#define G (*(struct globals*)&bb_common_bufsiz1) 126struct BUG_G_too_big { 127 char BUG_G_too_big[sizeof(G) <= COMMON_BUFSIZE ? 1 : -1]; 128}; 129#define INIT_G() do { \ 130 G.sed_cmd_tail = &G.sed_cmd_head; \ 131} while (0) 132 133 134#if ENABLE_FEATURE_CLEAN_UP 135static void sed_free_and_close_stuff(void) 136{ 137 sed_cmd_t *sed_cmd = G.sed_cmd_head.next; 138 139 llist_free(G.append_head, free); 140 141 while (sed_cmd) { 142 sed_cmd_t *sed_cmd_next = sed_cmd->next; 143 144 if (sed_cmd->sw_file) 145 xprint_and_close_file(sed_cmd->sw_file); 146 147 if (sed_cmd->beg_match) { 148 regfree(sed_cmd->beg_match); 149 free(sed_cmd->beg_match); 150 } 151 if (sed_cmd->end_match) { 152 regfree(sed_cmd->end_match); 153 free(sed_cmd->end_match); 154 } 155 if (sed_cmd->sub_match) { 156 regfree(sed_cmd->sub_match); 157 free(sed_cmd->sub_match); 158 } 159 free(sed_cmd->string); 160 free(sed_cmd); 161 sed_cmd = sed_cmd_next; 162 } 163 164 free(G.hold_space); 165 166 while (G.current_input_file < G.input_file_count) 167 fclose(G.input_file_list[G.current_input_file++]); 168} 169#else 170void sed_free_and_close_stuff(void); 171#endif 172 173/* If something bad happens during -i operation, delete temp file */ 174 175static void cleanup_outname(void) 176{ 177 if (G.outname) unlink(G.outname); 178} 179 180/* strcpy, replacing "\from" with 'to'. If to is NUL, replacing "\any" with 'any' */ 181 182static void parse_escapes(char *dest, const char *string, int len, char from, char to) 183{ 184 int i = 0; 185 186 while (i < len) { 187 if (string[i] == '\\') { 188 if (!to || string[i+1] == from) { 189 *dest++ = to ? to : string[i+1]; 190 i += 2; 191 continue; 192 } 193 *dest++ = string[i++]; 194 } 195 /* TODO: is it safe wrt a string with trailing '\\' ? */ 196 *dest++ = string[i++]; 197 } 198 *dest = '\0'; 199} 200 201static char *copy_parsing_escapes(const char *string, int len) 202{ 203 char *dest = xmalloc(len + 1); 204 205 parse_escapes(dest, string, len, 'n', '\n'); 206 /* GNU sed also recognizes \t */ 207 parse_escapes(dest, dest, strlen(dest), 't', '\t'); 208 return dest; 209} 210 211 212/* 213 * index_of_next_unescaped_regexp_delim - walks left to right through a string 214 * beginning at a specified index and returns the index of the next regular 215 * expression delimiter (typically a forward slash ('/')) not preceded by 216 * a backslash ('\'). A negative delimiter disables square bracket checking. 217 */ 218static int index_of_next_unescaped_regexp_delim(int delimiter, const char *str) 219{ 220 int bracket = -1; 221 int escaped = 0; 222 int idx = 0; 223 char ch; 224 225 if (delimiter < 0) { 226 bracket--; 227 delimiter = -delimiter; 228 } 229 230 for (; (ch = str[idx]); idx++) { 231 if (bracket >= 0) { 232 if (ch == ']' && !(bracket == idx - 1 || (bracket == idx - 2 233 && str[idx - 1] == '^'))) 234 bracket = -1; 235 } else if (escaped) 236 escaped = 0; 237 else if (ch == '\\') 238 escaped = 1; 239 else if (bracket == -1 && ch == '[') 240 bracket = idx; 241 else if (ch == delimiter) 242 return idx; 243 } 244 245 /* if we make it to here, we've hit the end of the string */ 246 bb_error_msg_and_die("unmatched '%c'", delimiter); 247} 248 249/* 250 * Returns the index of the third delimiter 251 */ 252static int parse_regex_delim(const char *cmdstr, char **match, char **replace) 253{ 254 const char *cmdstr_ptr = cmdstr; 255 char delimiter; 256 int idx = 0; 257 258 /* verify that the 's' or 'y' is followed by something. That something 259 * (typically a 'slash') is now our regexp delimiter... */ 260 if (*cmdstr == '\0') 261 bb_error_msg_and_die("bad format in substitution expression"); 262 delimiter = *cmdstr_ptr++; 263 264 /* save the match string */ 265 idx = index_of_next_unescaped_regexp_delim(delimiter, cmdstr_ptr); 266 *match = copy_parsing_escapes(cmdstr_ptr, idx); 267 268 /* save the replacement string */ 269 cmdstr_ptr += idx + 1; 270 idx = index_of_next_unescaped_regexp_delim(-delimiter, cmdstr_ptr); 271 *replace = copy_parsing_escapes(cmdstr_ptr, idx); 272 273 return ((cmdstr_ptr - cmdstr) + idx); 274} 275 276/* 277 * returns the index in the string just past where the address ends. 278 */ 279static int get_address(const char *my_str, int *linenum, regex_t ** regex) 280{ 281 const char *pos = my_str; 282 283 if (isdigit(*my_str)) { 284 *linenum = strtol(my_str, (char**)&pos, 10); 285 /* endstr shouldnt ever equal NULL */ 286 } else if (*my_str == '$') { 287 *linenum = -1; 288 pos++; 289 } else if (*my_str == '/' || *my_str == '\\') { 290 int next; 291 char delimiter; 292 char *temp; 293 294 delimiter = '/'; 295 if (*my_str == '\\') delimiter = *++pos; 296 next = index_of_next_unescaped_regexp_delim(delimiter, ++pos); 297 temp = copy_parsing_escapes(pos, next); 298 *regex = xmalloc(sizeof(regex_t)); 299 xregcomp(*regex, temp, G.regex_type|REG_NEWLINE); 300 free(temp); 301 /* Move position to next character after last delimiter */ 302 pos += (next+1); 303 } 304 return pos - my_str; 305} 306 307/* Grab a filename. Whitespace at start is skipped, then goes to EOL. */ 308static int parse_file_cmd(/*sed_cmd_t *sed_cmd,*/ const char *filecmdstr, char **retval) 309{ 310 int start = 0, idx, hack = 0; 311 312 /* Skip whitespace, then grab filename to end of line */ 313 while (isspace(filecmdstr[start])) 314 start++; 315 idx = start; 316 while (filecmdstr[idx] && filecmdstr[idx] != '\n') 317 idx++; 318 319 /* If lines glued together, put backslash back. */ 320 if (filecmdstr[idx] == '\n') 321 hack = 1; 322 if (idx == start) 323 bb_error_msg_and_die("empty filename"); 324 *retval = xstrndup(filecmdstr+start, idx-start+hack+1); 325 if (hack) 326 (*retval)[idx] = '\\'; 327 328 return idx; 329} 330 331static int parse_subst_cmd(sed_cmd_t *sed_cmd, const char *substr) 332{ 333 int cflags = G.regex_type; 334 char *match; 335 int idx; 336 337 /* 338 * A substitution command should look something like this: 339 * s/match/replace/ #gIpw 340 * || | ||| 341 * mandatory optional 342 */ 343 idx = parse_regex_delim(substr, &match, &sed_cmd->string); 344 345 /* determine the number of back references in the match string */ 346 /* Note: we compute this here rather than in the do_subst_command() 347 * function to save processor time, at the expense of a little more memory 348 * (4 bits) per sed_cmd */ 349 350 /* process the flags */ 351 352 sed_cmd->which_match = 1; 353 while (substr[++idx]) { 354 /* Parse match number */ 355 if (isdigit(substr[idx])) { 356 if (match[0] != '^') { 357 /* Match 0 treated as all, multiple matches we take the last one. */ 358 const char *pos = substr + idx; 359/* FIXME: error check? */ 360 sed_cmd->which_match = (unsigned)strtol(substr+idx, (char**) &pos, 10); 361 idx = pos - substr; 362 } 363 continue; 364 } 365 /* Skip spaces */ 366 if (isspace(substr[idx])) 367 continue; 368 369 switch (substr[idx]) { 370 /* Replace all occurrences */ 371 case 'g': 372 if (match[0] != '^') 373 sed_cmd->which_match = 0; 374 break; 375 /* Print pattern space */ 376 case 'p': 377 sed_cmd->sub_p = 1; 378 break; 379 /* Write to file */ 380 case 'w': 381 { 382 char *temp; 383 idx += parse_file_cmd(/*sed_cmd,*/ substr+idx, &temp); 384 break; 385 } 386 /* Ignore case (gnu exension) */ 387 case 'I': 388 cflags |= REG_ICASE; 389 break; 390 /* Comment */ 391 case '#': 392 // while (substr[++idx]) continue; 393 idx += strlen(substr + idx); // same 394 /* Fall through */ 395 /* End of command */ 396 case ';': 397 case '}': 398 goto out; 399 default: 400 bb_error_msg_and_die("bad option in substitution expression"); 401 } 402 } 403 out: 404 /* compile the match string into a regex */ 405 if (*match != '\0') { 406 /* If match is empty, we use last regex used at runtime */ 407 sed_cmd->sub_match = xmalloc(sizeof(regex_t)); 408 xregcomp(sed_cmd->sub_match, match, cflags); 409 } 410 free(match); 411 412 return idx; 413} 414 415/* 416 * Process the commands arguments 417 */ 418static const char *parse_cmd_args(sed_cmd_t *sed_cmd, const char *cmdstr) 419{ 420 /* handle (s)ubstitution command */ 421 if (sed_cmd->cmd == 's') 422 cmdstr += parse_subst_cmd(sed_cmd, cmdstr); 423 /* handle edit cmds: (a)ppend, (i)nsert, and (c)hange */ 424 else if (strchr("aic", sed_cmd->cmd)) { 425 if ((sed_cmd->end_line || sed_cmd->end_match) && sed_cmd->cmd != 'c') 426 bb_error_msg_and_die("only a beginning address can be specified for edit commands"); 427 for (;;) { 428 if (*cmdstr == '\n' || *cmdstr == '\\') { 429 cmdstr++; 430 break; 431 } 432 if (!isspace(*cmdstr)) 433 break; 434 cmdstr++; 435 } 436 sed_cmd->string = xstrdup(cmdstr); 437 /* "\anychar" -> "anychar" */ 438 parse_escapes(sed_cmd->string, sed_cmd->string, strlen(cmdstr), '\0', '\0'); 439 cmdstr += strlen(cmdstr); 440 /* handle file cmds: (r)ead */ 441 } else if (strchr("rw", sed_cmd->cmd)) { 442 if (sed_cmd->end_line || sed_cmd->end_match) 443 bb_error_msg_and_die("command only uses one address"); 444 cmdstr += parse_file_cmd(/*sed_cmd,*/ cmdstr, &sed_cmd->string); 445 if (sed_cmd->cmd == 'w') { 446 sed_cmd->sw_file = xfopen_for_write(sed_cmd->string); 447 sed_cmd->sw_last_char = '\n'; 448 } 449 /* handle branch commands */ 450 } else if (strchr(":btT", sed_cmd->cmd)) { 451 int length; 452 453 cmdstr = skip_whitespace(cmdstr); 454 length = strcspn(cmdstr, semicolon_whitespace); 455 if (length) { 456 sed_cmd->string = xstrndup(cmdstr, length); 457 cmdstr += length; 458 } 459 } 460 /* translation command */ 461 else if (sed_cmd->cmd == 'y') { 462 char *match, *replace; 463 int i = cmdstr[0]; 464 465 cmdstr += parse_regex_delim(cmdstr, &match, &replace)+1; 466 /* \n already parsed, but \delimiter needs unescaping. */ 467 parse_escapes(match, match, strlen(match), i, i); 468 parse_escapes(replace, replace, strlen(replace), i, i); 469 470 sed_cmd->string = xzalloc((strlen(match) + 1) * 2); 471 for (i = 0; match[i] && replace[i]; i++) { 472 sed_cmd->string[i*2] = match[i]; 473 sed_cmd->string[i*2+1] = replace[i]; 474 } 475 free(match); 476 free(replace); 477 } 478 /* if it wasnt a single-letter command that takes no arguments 479 * then it must be an invalid command. 480 */ 481 else if (strchr("dDgGhHlnNpPqx={}", sed_cmd->cmd) == 0) { 482 bb_error_msg_and_die("unsupported command %c", sed_cmd->cmd); 483 } 484 485 /* give back whatever's left over */ 486 return cmdstr; 487} 488 489 490/* Parse address+command sets, skipping comment lines. */ 491 492static void add_cmd(const char *cmdstr) 493{ 494 sed_cmd_t *sed_cmd; 495 unsigned len, n; 496 497 /* Append this line to any unfinished line from last time. */ 498 if (G.add_cmd_line) { 499 char *tp = xasprintf("%s\n%s", G.add_cmd_line, cmdstr); 500 free(G.add_cmd_line); 501 cmdstr = G.add_cmd_line = tp; 502 } 503 504 /* If this line ends with unescaped backslash, request next line. */ 505 n = len = strlen(cmdstr); 506 while (n && cmdstr[n-1] == '\\') 507 n--; 508 if ((len - n) & 1) { /* if odd number of trailing backslashes */ 509 if (!G.add_cmd_line) 510 G.add_cmd_line = xstrdup(cmdstr); 511 G.add_cmd_line[len-1] = '\0'; 512 return; 513 } 514 515 /* Loop parsing all commands in this line. */ 516 while (*cmdstr) { 517 /* Skip leading whitespace and semicolons */ 518 cmdstr += strspn(cmdstr, semicolon_whitespace); 519 520 /* If no more commands, exit. */ 521 if (!*cmdstr) break; 522 523 /* if this is a comment, jump past it and keep going */ 524 if (*cmdstr == '#') { 525 /* "#n" is the same as using -n on the command line */ 526 if (cmdstr[1] == 'n') 527 G.be_quiet++; 528 cmdstr = strpbrk(cmdstr, "\n\r"); 529 if (!cmdstr) break; 530 continue; 531 } 532 533 /* parse the command 534 * format is: [addr][,addr][!]cmd 535 * |----||-----||-| 536 * part1 part2 part3 537 */ 538 539 sed_cmd = xzalloc(sizeof(sed_cmd_t)); 540 541 /* first part (if present) is an address: either a '$', a number or a /regex/ */ 542 cmdstr += get_address(cmdstr, &sed_cmd->beg_line, &sed_cmd->beg_match); 543 544 /* second part (if present) will begin with a comma */ 545 if (*cmdstr == ',') { 546 int idx; 547 548 cmdstr++; 549 idx = get_address(cmdstr, &sed_cmd->end_line, &sed_cmd->end_match); 550 if (!idx) 551 bb_error_msg_and_die("no address after comma"); 552 cmdstr += idx; 553 } 554 555 /* skip whitespace before the command */ 556 cmdstr = skip_whitespace(cmdstr); 557 558 /* Check for inversion flag */ 559 if (*cmdstr == '!') { 560 sed_cmd->invert = 1; 561 cmdstr++; 562 563 /* skip whitespace before the command */ 564 cmdstr = skip_whitespace(cmdstr); 565 } 566 567 /* last part (mandatory) will be a command */ 568 if (!*cmdstr) 569 bb_error_msg_and_die("missing command"); 570 sed_cmd->cmd = *cmdstr++; 571 cmdstr = parse_cmd_args(sed_cmd, cmdstr); 572 573 /* Add the command to the command array */ 574 G.sed_cmd_tail->next = sed_cmd; 575 G.sed_cmd_tail = G.sed_cmd_tail->next; 576 } 577 578 /* If we glued multiple lines together, free the memory. */ 579 free(G.add_cmd_line); 580 G.add_cmd_line = NULL; 581} 582 583/* Append to a string, reallocating memory as necessary. */ 584 585#define PIPE_GROW 64 586 587static void pipe_putc(char c) 588{ 589 if (G.pipeline.idx == G.pipeline.len) { 590 G.pipeline.buf = xrealloc(G.pipeline.buf, 591 G.pipeline.len + PIPE_GROW); 592 G.pipeline.len += PIPE_GROW; 593 } 594 G.pipeline.buf[G.pipeline.idx++] = c; 595} 596 597static void do_subst_w_backrefs(char *line, char *replace) 598{ 599 int i, j; 600 601 /* go through the replacement string */ 602 for (i = 0; replace[i]; i++) { 603 /* if we find a backreference (\1, \2, etc.) print the backref'ed * text */ 604 if (replace[i] == '\\') { 605 unsigned backref = replace[++i] - '0'; 606 if (backref <= 9) { 607 /* print out the text held in G.regmatch[backref] */ 608 if (G.regmatch[backref].rm_so != -1) { 609 j = G.regmatch[backref].rm_so; 610 while (j < G.regmatch[backref].rm_eo) 611 pipe_putc(line[j++]); 612 } 613 continue; 614 } 615 /* I _think_ it is impossible to get '\' to be 616 * the last char in replace string. Thus we dont check 617 * for replace[i] == NUL. (counterexample anyone?) */ 618 /* if we find a backslash escaped character, print the character */ 619 pipe_putc(replace[i]); 620 continue; 621 } 622 /* if we find an unescaped '&' print out the whole matched text. */ 623 if (replace[i] == '&') { 624 j = G.regmatch[0].rm_so; 625 while (j < G.regmatch[0].rm_eo) 626 pipe_putc(line[j++]); 627 continue; 628 } 629 /* Otherwise just output the character. */ 630 pipe_putc(replace[i]); 631 } 632} 633 634static int do_subst_command(sed_cmd_t *sed_cmd, char **line_p) 635{ 636 char *line = *line_p; 637 int altered = 0; 638 unsigned match_count = 0; 639 regex_t *current_regex; 640 641 current_regex = sed_cmd->sub_match; 642 /* Handle empty regex. */ 643 if (!current_regex) { 644 current_regex = G.previous_regex_ptr; 645 if (!current_regex) 646 bb_error_msg_and_die("no previous regexp"); 647 } 648 G.previous_regex_ptr = current_regex; 649 650 /* Find the first match */ 651 if (REG_NOMATCH == regexec(current_regex, line, 10, G.regmatch, 0)) 652 return 0; 653 654 /* Initialize temporary output buffer. */ 655 G.pipeline.buf = xmalloc(PIPE_GROW); 656 G.pipeline.len = PIPE_GROW; 657 G.pipeline.idx = 0; 658 659 /* Now loop through, substituting for matches */ 660 do { 661 int i; 662 663 /* Work around bug in glibc regexec, demonstrated by: 664 echo " a.b" | busybox sed 's [^ .]* x g' 665 The match_count check is so not to break 666 echo "hi" | busybox sed 's/^/!/g' */ 667 if (!G.regmatch[0].rm_so && !G.regmatch[0].rm_eo && match_count) { 668 pipe_putc(*line++); 669 continue; 670 } 671 672 match_count++; 673 674 /* If we aren't interested in this match, output old line to 675 end of match and continue */ 676 if (sed_cmd->which_match 677 && (sed_cmd->which_match != match_count) 678 ) { 679 for (i = 0; i < G.regmatch[0].rm_eo; i++) 680 pipe_putc(*line++); 681 continue; 682 } 683 684 /* print everything before the match */ 685 for (i = 0; i < G.regmatch[0].rm_so; i++) 686 pipe_putc(line[i]); 687 688 /* then print the substitution string */ 689 do_subst_w_backrefs(line, sed_cmd->string); 690 691 /* advance past the match */ 692 line += G.regmatch[0].rm_eo; 693 /* flag that something has changed */ 694 altered++; 695 696 /* if we're not doing this globally, get out now */ 697 if (sed_cmd->which_match) 698 break; 699 700//maybe (G.regmatch[0].rm_eo ? REG_NOTBOL : 0) instead of unconditional REG_NOTBOL? 701 } while (*line && regexec(current_regex, line, 10, G.regmatch, REG_NOTBOL) != REG_NOMATCH); 702 703 /* Copy rest of string into output pipeline */ 704 while (1) { 705 char c = *line++; 706 pipe_putc(c); 707 if (c == '\0') 708 break; 709 } 710 711 free(*line_p); 712 *line_p = G.pipeline.buf; 713 return altered; 714} 715 716/* Set command pointer to point to this label. (Does not handle null label.) */ 717static sed_cmd_t *branch_to(char *label) 718{ 719 sed_cmd_t *sed_cmd; 720 721 for (sed_cmd = G.sed_cmd_head.next; sed_cmd; sed_cmd = sed_cmd->next) { 722 if (sed_cmd->cmd == ':' && sed_cmd->string && !strcmp(sed_cmd->string, label)) { 723 return sed_cmd; 724 } 725 } 726 bb_error_msg_and_die("can't find label for jump to '%s'", label); 727} 728 729static void append(char *s) 730{ 731 llist_add_to_end(&G.append_head, xstrdup(s)); 732} 733 734static void flush_append(void) 735{ 736 char *data; 737 738 /* Output appended lines. */ 739 while ((data = (char *)llist_pop(&G.append_head))) { 740 fprintf(G.nonstdout, "%s\n", data); 741 free(data); 742 } 743} 744 745static void add_input_file(FILE *file) 746{ 747 G.input_file_list = xrealloc_vector(G.input_file_list, 2, G.input_file_count); 748 G.input_file_list[G.input_file_count++] = file; 749} 750 751/* Get next line of input from G.input_file_list, flushing append buffer and 752 * noting if we ran out of files without a newline on the last line we read. 753 */ 754enum { 755 NO_EOL_CHAR = 1, 756 LAST_IS_NUL = 2, 757}; 758static char *get_next_line(char *gets_char) 759{ 760 char *temp = NULL; 761 int len; 762 char gc; 763 764 flush_append(); 765 766 /* will be returned if last line in the file 767 * doesn't end with either '\n' or '\0' */ 768 gc = NO_EOL_CHAR; 769 while (G.current_input_file < G.input_file_count) { 770 FILE *fp = G.input_file_list[G.current_input_file]; 771 /* Read line up to a newline or NUL byte, inclusive, 772 * return malloc'ed char[]. length of the chunk read 773 * is stored in len. NULL if EOF/error */ 774 temp = bb_get_chunk_from_file(fp, &len); 775 if (temp) { 776 /* len > 0 here, it's ok to do temp[len-1] */ 777 char c = temp[len-1]; 778 if (c == '\n' || c == '\0') { 779 temp[len-1] = '\0'; 780 gc = c; 781 if (c == '\0') { 782 int ch = fgetc(fp); 783 if (ch != EOF) 784 ungetc(ch, fp); 785 else 786 gc = LAST_IS_NUL; 787 } 788 } 789 /* else we put NO_EOL_CHAR into *gets_char */ 790 break; 791 792 /* NB: I had the idea of peeking next file(s) and returning 793 * NO_EOL_CHAR only if it is the *last* non-empty 794 * input file. But there is a case where this won't work: 795 * file1: "a woo\nb woo" 796 * file2: "c no\nd no" 797 * sed -ne 's/woo/bang/p' input1 input2 => "a bang\nb bang" 798 * (note: *no* newline after "b bang"!) */ 799 } 800 /* Close this file and advance to next one */ 801 fclose(fp); 802 G.current_input_file++; 803 } 804 *gets_char = gc; 805 return temp; 806} 807 808/* Output line of text. */ 809/* Note: 810 * The tricks with NO_EOL_CHAR and last_puts_char are there to emulate gnu sed. 811 * Without them, we had this: 812 * echo -n thingy >z1 813 * echo -n again >z2 814 * >znull 815 * sed "s/i/z/" z1 z2 znull | hexdump -vC 816 * output: 817 * gnu sed 4.1.5: 818 * 00000000 74 68 7a 6e 67 79 0a 61 67 61 7a 6e |thzngy.agazn| 819 * bbox: 820 * 00000000 74 68 7a 6e 67 79 61 67 61 7a 6e |thzngyagazn| 821 */ 822static void puts_maybe_newline(char *s, FILE *file, char *last_puts_char, char last_gets_char) 823{ 824 char lpc = *last_puts_char; 825 826 /* Need to insert a '\n' between two files because first file's 827 * last line wasn't terminated? */ 828 if (lpc != '\n' && lpc != '\0') { 829 fputc('\n', file); 830 lpc = '\n'; 831 } 832 fputs(s, file); 833 834 /* 'x' - just something which is not '\n', '\0' or NO_EOL_CHAR */ 835 if (s[0]) 836 lpc = 'x'; 837 838 /* had trailing '\0' and it was last char of file? */ 839 if (last_gets_char == LAST_IS_NUL) { 840 fputc('\0', file); 841 lpc = 'x'; /* */ 842 } else 843 /* had trailing '\n' or '\0'? */ 844 if (last_gets_char != NO_EOL_CHAR) { 845 fputc(last_gets_char, file); 846 lpc = last_gets_char; 847 } 848 849 if (ferror(file)) { 850 xfunc_error_retval = 4; /* It's what gnu sed exits with... */ 851 bb_error_msg_and_die(bb_msg_write_error); 852 } 853 *last_puts_char = lpc; 854} 855 856#define sed_puts(s, n) (puts_maybe_newline(s, G.nonstdout, &last_puts_char, n)) 857 858static int beg_match(sed_cmd_t *sed_cmd, const char *pattern_space) 859{ 860 int retval = sed_cmd->beg_match && !regexec(sed_cmd->beg_match, pattern_space, 0, NULL, 0); 861 if (retval) 862 G.previous_regex_ptr = sed_cmd->beg_match; 863 return retval; 864} 865 866/* Process all the lines in all the files */ 867 868static void process_files(void) 869{ 870 char *pattern_space, *next_line; 871 int linenum = 0; 872 char last_puts_char = '\n'; 873 char last_gets_char, next_gets_char; 874 sed_cmd_t *sed_cmd; 875 int substituted; 876 877 /* Prime the pump */ 878 next_line = get_next_line(&next_gets_char); 879 880 /* Go through every line in each file */ 881 again: 882 substituted = 0; 883 884 /* Advance to next line. Stop if out of lines. */ 885 pattern_space = next_line; 886 if (!pattern_space) 887 return; 888 last_gets_char = next_gets_char; 889 890 /* Read one line in advance so we can act on the last line, 891 * the '$' address */ 892 next_line = get_next_line(&next_gets_char); 893 linenum++; 894 895 /* For every line, go through all the commands */ 896 restart: 897 for (sed_cmd = G.sed_cmd_head.next; sed_cmd; sed_cmd = sed_cmd->next) { 898 int old_matched, matched; 899 900 old_matched = sed_cmd->in_match; 901 902 /* Determine if this command matches this line: */ 903 904 //bb_error_msg("match1:%d", sed_cmd->in_match); 905 //bb_error_msg("match2:%d", (!sed_cmd->beg_line && !sed_cmd->end_line 906 // && !sed_cmd->beg_match && !sed_cmd->end_match)); 907 //bb_error_msg("match3:%d", (sed_cmd->beg_line > 0 908 // && (sed_cmd->end_line || sed_cmd->end_match 909 // ? (sed_cmd->beg_line <= linenum) 910 // : (sed_cmd->beg_line == linenum) 911 // ) 912 // ) 913 //bb_error_msg("match4:%d", (beg_match(sed_cmd, pattern_space))); 914 //bb_error_msg("match5:%d", (sed_cmd->beg_line == -1 && next_line == NULL)); 915 916 /* Are we continuing a previous multi-line match? */ 917 sed_cmd->in_match = sed_cmd->in_match 918 /* Or is no range necessary? */ 919 || (!sed_cmd->beg_line && !sed_cmd->end_line 920 && !sed_cmd->beg_match && !sed_cmd->end_match) 921 /* Or did we match the start of a numerical range? */ 922 || (sed_cmd->beg_line > 0 923 && (sed_cmd->end_line || sed_cmd->end_match 924 /* note: even if end is numeric and is < linenum too, 925 * GNU sed matches! We match too */ 926 ? (sed_cmd->beg_line <= linenum) /* N,end */ 927 : (sed_cmd->beg_line == linenum) /* N */ 928 ) 929 ) 930 /* Or does this line match our begin address regex? */ 931 || (beg_match(sed_cmd, pattern_space)) 932 /* Or did we match last line of input? */ 933 || (sed_cmd->beg_line == -1 && next_line == NULL); 934 935 /* Snapshot the value */ 936 matched = sed_cmd->in_match; 937 938 //bb_error_msg("cmd:'%c' matched:%d beg_line:%d end_line:%d linenum:%d", 939 //sed_cmd->cmd, matched, sed_cmd->beg_line, sed_cmd->end_line, linenum); 940 941 /* Is this line the end of the current match? */ 942 943 if (matched) { 944 /* once matched, "n,xxx" range is dead, disabling it */ 945 if (sed_cmd->beg_line > 0 946 && !(option_mask32 & OPT_in_place) /* but not for -i */ 947 ) { 948 sed_cmd->beg_line = -2; 949 } 950 sed_cmd->in_match = !( 951 /* has the ending line come, or is this a single address command? */ 952 (sed_cmd->end_line ? 953 sed_cmd->end_line == -1 ? 954 !next_line 955 : (sed_cmd->end_line <= linenum) 956 : !sed_cmd->end_match 957 ) 958 /* or does this line matches our last address regex */ 959 || (sed_cmd->end_match && old_matched 960 && (regexec(sed_cmd->end_match, 961 pattern_space, 0, NULL, 0) == 0)) 962 ); 963 } 964 965 /* Skip blocks of commands we didn't match */ 966 if (sed_cmd->cmd == '{') { 967 if (sed_cmd->invert ? matched : !matched) { 968 unsigned nest_cnt = 0; 969 while (1) { 970 if (sed_cmd->cmd == '{') 971 nest_cnt++; 972 if (sed_cmd->cmd == '}') { 973 nest_cnt--; 974 if (nest_cnt == 0) 975 break; 976 } 977 sed_cmd = sed_cmd->next; 978 if (!sed_cmd) 979 bb_error_msg_and_die("unterminated {"); 980 } 981 } 982 continue; 983 } 984 985 /* Okay, so did this line match? */ 986 if (sed_cmd->invert ? matched : !matched) 987 continue; /* no */ 988 989 /* Update last used regex in case a blank substitute BRE is found */ 990 if (sed_cmd->beg_match) { 991 G.previous_regex_ptr = sed_cmd->beg_match; 992 } 993 994 /* actual sedding */ 995 //bb_error_msg("pattern_space:'%s' next_line:'%s' cmd:%c", 996 //pattern_space, next_line, sed_cmd->cmd); 997 switch (sed_cmd->cmd) { 998 999 /* Print line number */ 1000 case '=': 1001 fprintf(G.nonstdout, "%d\n", linenum); 1002 break; 1003 1004 /* Write the current pattern space up to the first newline */ 1005 case 'P': 1006 { 1007 char *tmp = strchr(pattern_space, '\n'); 1008 if (tmp) { 1009 *tmp = '\0'; 1010 /* TODO: explain why '\n' below */ 1011 sed_puts(pattern_space, '\n'); 1012 *tmp = '\n'; 1013 break; 1014 } 1015 /* Fall Through */ 1016 } 1017 1018 /* Write the current pattern space to output */ 1019 case 'p': 1020 /* NB: we print this _before_ the last line 1021 * (of current file) is printed. Even if 1022 * that line is nonterminated, we print 1023 * '\n' here (gnu sed does the same) */ 1024 sed_puts(pattern_space, '\n'); 1025 break; 1026 /* Delete up through first newline */ 1027 case 'D': 1028 { 1029 char *tmp = strchr(pattern_space, '\n'); 1030 if (tmp) { 1031 overlapping_strcpy(pattern_space, tmp + 1); 1032 goto restart; 1033 } 1034 } 1035 /* discard this line. */ 1036 case 'd': 1037 goto discard_line; 1038 1039 /* Substitute with regex */ 1040 case 's': 1041 if (!do_subst_command(sed_cmd, &pattern_space)) 1042 break; 1043 substituted |= 1; 1044 1045 /* handle p option */ 1046 if (sed_cmd->sub_p) 1047 sed_puts(pattern_space, last_gets_char); 1048 /* handle w option */ 1049 if (sed_cmd->sw_file) 1050 puts_maybe_newline( 1051 pattern_space, sed_cmd->sw_file, 1052 &sed_cmd->sw_last_char, last_gets_char); 1053 break; 1054 1055 /* Append line to linked list to be printed later */ 1056 case 'a': 1057 append(sed_cmd->string); 1058 break; 1059 1060 /* Insert text before this line */ 1061 case 'i': 1062 sed_puts(sed_cmd->string, '\n'); 1063 break; 1064 1065 /* Cut and paste text (replace) */ 1066 case 'c': 1067 /* Only triggers on last line of a matching range. */ 1068 if (!sed_cmd->in_match) 1069 sed_puts(sed_cmd->string, '\n'); 1070 goto discard_line; 1071 1072 /* Read file, append contents to output */ 1073 case 'r': 1074 { 1075 FILE *rfile; 1076 rfile = fopen_for_read(sed_cmd->string); 1077 if (rfile) { 1078 char *line; 1079 1080 while ((line = xmalloc_fgetline(rfile)) 1081 != NULL) 1082 append(line); 1083 xprint_and_close_file(rfile); 1084 } 1085 1086 break; 1087 } 1088 1089 /* Write pattern space to file. */ 1090 case 'w': 1091 puts_maybe_newline( 1092 pattern_space, sed_cmd->sw_file, 1093 &sed_cmd->sw_last_char, last_gets_char); 1094 break; 1095 1096 /* Read next line from input */ 1097 case 'n': 1098 if (!G.be_quiet) 1099 sed_puts(pattern_space, last_gets_char); 1100 if (next_line) { 1101 free(pattern_space); 1102 pattern_space = next_line; 1103 last_gets_char = next_gets_char; 1104 next_line = get_next_line(&next_gets_char); 1105 substituted = 0; 1106 linenum++; 1107 break; 1108 } 1109 /* fall through */ 1110 1111 /* Quit. End of script, end of input. */ 1112 case 'q': 1113 /* Exit the outer while loop */ 1114 free(next_line); 1115 next_line = NULL; 1116 goto discard_commands; 1117 1118 /* Append the next line to the current line */ 1119 case 'N': 1120 { 1121 int len; 1122 /* If no next line, jump to end of script and exit. */ 1123 /* http://www.gnu.org/software/sed/manual/sed.html: 1124 * "Most versions of sed exit without printing anything 1125 * when the N command is issued on the last line of 1126 * a file. GNU sed prints pattern space before exiting 1127 * unless of course the -n command switch has been 1128 * specified. This choice is by design." 1129 */ 1130 if (next_line == NULL) { 1131 //goto discard_line; 1132 goto discard_commands; /* GNU behavior */ 1133 } 1134 /* Append next_line, read new next_line. */ 1135 len = strlen(pattern_space); 1136 pattern_space = xrealloc(pattern_space, len + strlen(next_line) + 2); 1137 pattern_space[len] = '\n'; 1138 strcpy(pattern_space + len+1, next_line); 1139 last_gets_char = next_gets_char; 1140 next_line = get_next_line(&next_gets_char); 1141 linenum++; 1142 break; 1143 } 1144 1145 /* Test/branch if substitution occurred */ 1146 case 't': 1147 if (!substituted) break; 1148 substituted = 0; 1149 /* Fall through */ 1150 /* Test/branch if substitution didn't occur */ 1151 case 'T': 1152 if (substituted) break; 1153 /* Fall through */ 1154 /* Branch to label */ 1155 case 'b': 1156 if (!sed_cmd->string) goto discard_commands; 1157 else sed_cmd = branch_to(sed_cmd->string); 1158 break; 1159 /* Transliterate characters */ 1160 case 'y': 1161 { 1162 int i, j; 1163 for (i = 0; pattern_space[i]; i++) { 1164 for (j = 0; sed_cmd->string[j]; j += 2) { 1165 if (pattern_space[i] == sed_cmd->string[j]) { 1166 pattern_space[i] = sed_cmd->string[j + 1]; 1167 break; 1168 } 1169 } 1170 } 1171 1172 break; 1173 } 1174 case 'g': /* Replace pattern space with hold space */ 1175 free(pattern_space); 1176 pattern_space = xstrdup(G.hold_space ? G.hold_space : ""); 1177 break; 1178 case 'G': /* Append newline and hold space to pattern space */ 1179 { 1180 int pattern_space_size = 2; 1181 int hold_space_size = 0; 1182 1183 if (pattern_space) 1184 pattern_space_size += strlen(pattern_space); 1185 if (G.hold_space) 1186 hold_space_size = strlen(G.hold_space); 1187 pattern_space = xrealloc(pattern_space, 1188 pattern_space_size + hold_space_size); 1189 if (pattern_space_size == 2) 1190 pattern_space[0] = 0; 1191 strcat(pattern_space, "\n"); 1192 if (G.hold_space) 1193 strcat(pattern_space, G.hold_space); 1194 last_gets_char = '\n'; 1195 1196 break; 1197 } 1198 case 'h': /* Replace hold space with pattern space */ 1199 free(G.hold_space); 1200 G.hold_space = xstrdup(pattern_space); 1201 break; 1202 case 'H': /* Append newline and pattern space to hold space */ 1203 { 1204 int hold_space_size = 2; 1205 int pattern_space_size = 0; 1206 1207 if (G.hold_space) 1208 hold_space_size += strlen(G.hold_space); 1209 if (pattern_space) 1210 pattern_space_size = strlen(pattern_space); 1211 G.hold_space = xrealloc(G.hold_space, 1212 hold_space_size + pattern_space_size); 1213 1214 if (hold_space_size == 2) 1215 *G.hold_space = 0; 1216 strcat(G.hold_space, "\n"); 1217 if (pattern_space) 1218 strcat(G.hold_space, pattern_space); 1219 1220 break; 1221 } 1222 case 'x': /* Exchange hold and pattern space */ 1223 { 1224 char *tmp = pattern_space; 1225 pattern_space = G.hold_space ? G.hold_space : xzalloc(1); 1226 last_gets_char = '\n'; 1227 G.hold_space = tmp; 1228 break; 1229 } 1230 } /* switch */ 1231 } /* for each cmd */ 1232 1233 /* 1234 * Exit point from sedding... 1235 */ 1236 discard_commands: 1237 /* we will print the line unless we were told to be quiet ('-n') 1238 or if the line was suppressed (ala 'd'elete) */ 1239 if (!G.be_quiet) 1240 sed_puts(pattern_space, last_gets_char); 1241 1242 /* Delete and such jump here. */ 1243 discard_line: 1244 flush_append(); 1245 free(pattern_space); 1246 1247 goto again; 1248} 1249 1250/* It is possible to have a command line argument with embedded 1251 * newlines. This counts as multiple command lines. 1252 * However, newline can be escaped: 's/e/z\<newline>z/' 1253 * We check for this. 1254 */ 1255 1256static void add_cmd_block(char *cmdstr) 1257{ 1258 char *sv, *eol; 1259 1260 cmdstr = sv = xstrdup(cmdstr); 1261 do { 1262 eol = strchr(cmdstr, '\n'); 1263 next: 1264 if (eol) { 1265 /* Count preceding slashes */ 1266 int slashes = 0; 1267 char *sl = eol; 1268 1269 while (sl != cmdstr && *--sl == '\\') 1270 slashes++; 1271 /* Odd number of preceding slashes - newline is escaped */ 1272 if (slashes & 1) { 1273 overlapping_strcpy(eol - 1, eol); 1274 eol = strchr(eol, '\n'); 1275 goto next; 1276 } 1277 *eol = '\0'; 1278 } 1279 add_cmd(cmdstr); 1280 cmdstr = eol + 1; 1281 } while (eol); 1282 free(sv); 1283} 1284 1285int sed_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; 1286int sed_main(int argc UNUSED_PARAM, char **argv) 1287{ 1288 unsigned opt; 1289 llist_t *opt_e, *opt_f; 1290 int status = EXIT_SUCCESS; 1291 1292 INIT_G(); 1293 1294 /* destroy command strings on exit */ 1295 if (ENABLE_FEATURE_CLEAN_UP) atexit(sed_free_and_close_stuff); 1296 1297 /* Lie to autoconf when it starts asking stupid questions. */ 1298 if (argv[1] && !strcmp(argv[1], "--version")) { 1299 puts("This is not GNU sed version 4.0"); 1300 return 0; 1301 } 1302 1303 /* do normal option parsing */ 1304 opt_e = opt_f = NULL; 1305 opt_complementary = "e::f::" /* can occur multiple times */ 1306 "nn"; /* count -n */ 1307 /* -i must be first, to match OPT_in_place definition */ 1308 opt = getopt32(argv, "irne:f:", &opt_e, &opt_f, 1309 &G.be_quiet); /* counter for -n */ 1310 //argc -= optind; 1311 argv += optind; 1312 if (opt & OPT_in_place) { // -i 1313 atexit(cleanup_outname); 1314 } 1315 if (opt & 0x2) G.regex_type |= REG_EXTENDED; // -r 1316 //if (opt & 0x4) G.be_quiet++; // -n 1317 while (opt_e) { // -e 1318 add_cmd_block(llist_pop(&opt_e)); 1319 } 1320 while (opt_f) { // -f 1321 char *line; 1322 FILE *cmdfile; 1323 cmdfile = xfopen_for_read(llist_pop(&opt_f)); 1324 while ((line = xmalloc_fgetline(cmdfile)) != NULL) { 1325 add_cmd(line); 1326 free(line); 1327 } 1328 fclose(cmdfile); 1329 } 1330 /* if we didn't get a pattern from -e or -f, use argv[0] */ 1331 if (!(opt & 0x18)) { 1332 if (!*argv) 1333 bb_show_usage(); 1334 add_cmd_block(*argv++); 1335 } 1336 /* Flush any unfinished commands. */ 1337 add_cmd(""); 1338 1339 /* By default, we write to stdout */ 1340 G.nonstdout = stdout; 1341 1342 /* argv[0..(argc-1)] should be names of file to process. If no 1343 * files were specified or '-' was specified, take input from stdin. 1344 * Otherwise, we process all the files specified. */ 1345 if (argv[0] == NULL) { 1346 if (opt & OPT_in_place) 1347 bb_error_msg_and_die(bb_msg_requires_arg, "-i"); 1348 add_input_file(stdin); 1349 } else { 1350 int i; 1351 FILE *file; 1352 1353 for (i = 0; argv[i]; i++) { 1354 struct stat statbuf; 1355 int nonstdoutfd; 1356 1357 if (LONE_DASH(argv[i]) && !(opt & OPT_in_place)) { 1358 add_input_file(stdin); 1359 process_files(); 1360 continue; 1361 } 1362 file = fopen_or_warn(argv[i], "r"); 1363 if (!file) { 1364 status = EXIT_FAILURE; 1365 continue; 1366 } 1367 if (!(opt & OPT_in_place)) { 1368 add_input_file(file); 1369 continue; 1370 } 1371 1372 G.outname = xasprintf("%sXXXXXX", argv[i]); 1373 nonstdoutfd = mkstemp(G.outname); 1374 if (-1 == nonstdoutfd) 1375 bb_perror_msg_and_die("can't create temp file %s", G.outname); 1376 G.nonstdout = xfdopen_for_write(nonstdoutfd); 1377 1378 /* Set permissions/owner of output file */ 1379 fstat(fileno(file), &statbuf); 1380 /* chmod'ing AFTER chown would preserve suid/sgid bits, 1381 * but GNU sed 4.2.1 does not preserve them either */ 1382 fchmod(nonstdoutfd, statbuf.st_mode); 1383 fchown(nonstdoutfd, statbuf.st_uid, statbuf.st_gid); 1384 add_input_file(file); 1385 process_files(); 1386 fclose(G.nonstdout); 1387 1388 G.nonstdout = stdout; 1389 /* unlink(argv[i]); */ 1390 xrename(G.outname, argv[i]); 1391 free(G.outname); 1392 G.outname = NULL; 1393 } 1394 /* Here, to handle "sed 'cmds' nonexistent_file" case we did: 1395 * if (G.current_input_file >= G.input_file_count) 1396 * return status; 1397 * but it's not needed since process_files() works correctly 1398 * in this case too. */ 1399 } 1400 process_files(); 1401 1402 return status; 1403} 1404