| /* |
| * sed.c - very minimalist version of sed |
| * |
| * Copyright (C) 1999,2000 by Lineo, inc. |
| * Written by Mark Whitley <markw@lineo.com>, <markw@enol.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| * |
| */ |
| |
| /* |
| Supported features and commands in this version of sed: |
| |
| - comments ('#') |
| - Address matching: num|/matchstr/[,num|/matchstr/|$]command |
| - Commands: p, d, s/match/replace/[g] |
| |
| (Note: Specifying an address (range) to match is *optional*; commands |
| default to the whole pattern space if no specific address match was |
| requested.) |
| |
| Unsupported features: |
| |
| - transliteration (y/source-chars/dest-chars/) (use 'tr') |
| - no support for characters other than the '/' character for regex matches |
| - no pattern space hold space storing / swapping (x, etc.) |
| - no labels / branching (: label, b, t, and friends) |
| - and lots, lots more. |
| |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> /* for realloc() */ |
| #include <unistd.h> /* for getopt() */ |
| #include <regex.h> |
| #include <string.h> /* for strdup() */ |
| #include <errno.h> |
| #include <ctype.h> /* for isspace() */ |
| #include "internal.h" |
| |
| |
| /* externs */ |
| extern int optind; /* in unistd.h */ |
| extern char *optarg; /* ditto */ |
| |
| /* options */ |
| static int be_quiet = 0; |
| |
| struct sed_cmd { |
| |
| /* address storage */ |
| int beg_line; /* 'sed 1p' 0 == no begining line, apply commands to all lines */ |
| int end_line; /* 'sed 1,3p' 0 == no end line, use only beginning. -1 == $ */ |
| regex_t *beg_match; /* sed -e '/match/cmd' */ |
| regex_t *end_match; /* sed -e '/match/,/end_match/cmd' */ |
| |
| /* the command */ |
| char cmd; /* p,d,s (add more at your leisure :-) */ |
| |
| /* substitution command specific fields */ |
| regex_t *sub_match; /* sed -e 's/sub_match/replace/' */ |
| char *replace; /* sed -e 's/sub_match/replace/' XXX: who will hold the \1 \2 \3s? */ |
| unsigned int sub_g:1; /* sed -e 's/foo/bar/g' (global) */ |
| }; |
| |
| /* globals */ |
| static struct sed_cmd *sed_cmds = NULL; /* growable arrary holding a sequence of sed cmds */ |
| static int ncmds = 0; /* number of sed commands */ |
| |
| /*static char *cur_file = NULL;*/ /* file currently being processed XXX: do I need this? */ |
| |
| static const char sed_usage[] = |
| "sed [-Vhnef] pattern [files...]\n" |
| #ifndef BB_FEATURE_TRIVIAL_HELP |
| "\n" |
| "-n\tsuppress automatic printing of pattern space\n" |
| "-e script\tadd the script to the commands to be executed\n" |
| "-f scriptfile\tadd the contents of script-file to the commands to be executed\n" |
| "-h\tdisplay this help message\n" |
| "-V\toutput version information and exit\n" |
| "\n" |
| "If no -e or -f is given, the first non-option argument is taken as the\n" |
| "sed script to interpret. All remaining arguments are names of input\n" |
| "files; if no input files are specified, then the standard input is read.\n" |
| #endif |
| ; |
| |
| #if 0 |
| static void destroy_cmd_strs() |
| { |
| if (sed_cmds == NULL) |
| return; |
| |
| /* destroy all the elements in the array */ |
| while (--ncmds >= 0) { |
| |
| if (sed_cmds[ncmds].beg_match) { |
| regfree(sed_cmds[ncmds].beg_match); |
| free(sed_cmds[ncmds].beg_match); |
| } |
| if (sed_cmds[ncmds].end_match) { |
| regfree(sed_cmds[ncmds].end_match); |
| free(sed_cmds[ncmds].end_match); |
| } |
| if (sed_cmds[ncmds].sub_match) { |
| regfree(sed_cmds[ncmds].sub_match); |
| free(sed_cmds[ncmds].sub_match); |
| } |
| if (sed_cmds[ncmds].replace) |
| free(sed_cmds[ncmds].replace); |
| } |
| |
| /* destroy the array */ |
| free(sed_cmds); |
| sed_cmds = NULL; |
| } |
| #endif |
| |
| /* |
| * trim_str - trims leading and trailing space from a string |
| * |
| * Note: This returns a malloc'ed string so you must store and free it |
| * XXX: This should be in the utility.c file. |
| */ |
| static char *trim_str(const char *str) |
| { |
| int i; |
| char *retstr = strdup(str); |
| |
| /* trim leading whitespace */ |
| memmove(retstr, &retstr[strspn(retstr, " \n\t\v")], strlen(retstr)); |
| |
| /* trim trailing whitespace */ |
| i = strlen(retstr) - 1; |
| while (isspace(retstr[i])) |
| i--; |
| retstr[++i] = 0; |
| |
| /* Aside: |
| * |
| * you know, a strrspn() would really be nice cuz then we could say: |
| * |
| * retstr[strlen(retstr) - strrspn(retstr, " \n\t\v") + 1] = 0; |
| */ |
| |
| return retstr; |
| } |
| |
| /* |
| * index_of_unescaped_slash - walks left to right through a string beginning |
| * at a specified index and returns the index of the next unescaped slash. |
| */ |
| static int index_of_next_unescaped_slash(int idx, const char *str) |
| { |
| do { |
| idx++; |
| /* test if we've hit the end */ |
| if (str[idx] == 0) |
| return -1; |
| } while (str[idx] != '/' && str[idx - 1] != '\\'); |
| |
| return idx; |
| } |
| |
| /* |
| * returns the index in the string just past where the address ends. |
| */ |
| static int get_address(const char *str, int *line, regex_t **regex) |
| { |
| char *my_str = strdup(str); |
| int idx = 0; |
| |
| if (isdigit(my_str[idx])) { |
| do { |
| idx++; |
| } while (isdigit(my_str[idx])); |
| my_str[idx] = 0; |
| *line = atoi(my_str); |
| *regex = NULL; |
| } |
| else if (my_str[idx] == '$') { |
| *line = -1; |
| *regex = NULL; |
| idx++; |
| } |
| else if (my_str[idx] == '/') { |
| idx = index_of_next_unescaped_slash(idx, my_str); |
| if (idx == -1) |
| fatalError("unterminated match expression\n"); |
| my_str[idx] = '\0'; |
| *regex = (regex_t *)xmalloc(sizeof(regex_t)); |
| xregcomp(*regex, my_str+1, REG_NEWLINE); |
| } |
| else { |
| fprintf(stderr, "sed.c:get_address: no address found in string\n"); |
| fprintf(stderr, "\t(you probably didn't check the string you passed me)\n"); |
| idx = -1; |
| } |
| |
| free(my_str); |
| return idx; |
| } |
| |
| static char *strdup_substr(const char *str, int start, int end) |
| { |
| int size = end - start + 1; |
| char *newstr = xmalloc(size); |
| memcpy(newstr, str+start, size-1); |
| newstr[size-1] = '\0'; |
| return newstr; |
| } |
| |
| static void parse_cmd_str(struct sed_cmd *sed_cmd, const char *cmdstr) |
| { |
| int idx = 0; |
| |
| /* parse the command |
| * format is: [addr][,addr]cmd |
| * |----||-----||-| |
| * part1 part2 part3 |
| */ |
| |
| /* first part (if present) is an address: either a number or a /regex/ */ |
| if (isdigit(cmdstr[idx]) || cmdstr[idx] == '/') |
| idx = get_address(cmdstr, &sed_cmd->beg_line, &sed_cmd->beg_match); |
| |
| /* second part (if present) will begin with a comma */ |
| if (cmdstr[idx] == ',') |
| idx += get_address(&cmdstr[++idx], &sed_cmd->end_line, &sed_cmd->end_match); |
| |
| /* last part (mandatory) will be a command */ |
| if (cmdstr[idx] == '\0') |
| fatalError("missing command\n"); |
| if (!strchr("pds", cmdstr[idx])) /* <-- XXX add new commands here */ |
| fatalError("invalid command\n"); |
| sed_cmd->cmd = cmdstr[idx]; |
| /* special-case handling for 's' */ |
| if (sed_cmd->cmd == 's') { |
| int oldidx, cflags = REG_NEWLINE; |
| char *match; |
| /* format for substitution is: |
| * s/match/replace/gI |
| * | || |
| * mandatory optional |
| */ |
| |
| /* verify that we have an 's' followed by a 'slash' */ |
| if (cmdstr[++idx] != '/') |
| fatalError("bad format in substitution expression\n"); |
| |
| /* save the match string */ |
| oldidx = idx+1; |
| idx = index_of_next_unescaped_slash(idx, cmdstr); |
| if (idx == -1) |
| fatalError("bad format in substitution expression\n"); |
| match = strdup_substr(cmdstr, oldidx, idx); |
| |
| /* save the replacement string */ |
| oldidx = idx+1; |
| idx = index_of_next_unescaped_slash(idx, cmdstr); |
| if (idx == -1) |
| fatalError("bad format in substitution expression\n"); |
| sed_cmd->replace = strdup_substr(cmdstr, oldidx, idx); |
| |
| /* process the flags */ |
| while (cmdstr[++idx]) { |
| switch (cmdstr[idx]) { |
| case 'g': |
| sed_cmd->sub_g = 1; |
| break; |
| case 'I': |
| cflags |= REG_ICASE; |
| break; |
| default: |
| fatalError("bad option in substitution expression\n"); |
| } |
| } |
| |
| /* compile the regex */ |
| sed_cmd->sub_match = (regex_t *)xmalloc(sizeof(regex_t)); |
| xregcomp(sed_cmd->sub_match, match, cflags); |
| free(match); |
| } |
| } |
| |
| static void add_cmd_str(const char *cmdstr) |
| { |
| char *my_cmdstr = trim_str(cmdstr); |
| |
| /* if this is a comment, don't even bother */ |
| if (my_cmdstr[0] == '#') { |
| free(my_cmdstr); |
| return; |
| } |
| |
| /* grow the array */ |
| sed_cmds = realloc(sed_cmds, sizeof(struct sed_cmd) * (++ncmds)); |
| /* zero new element */ |
| memset(&sed_cmds[ncmds-1], 0, sizeof(struct sed_cmd)); |
| /* load command string into new array element */ |
| parse_cmd_str(&sed_cmds[ncmds-1], my_cmdstr); |
| } |
| |
| |
| static void load_cmd_file(char *filename) |
| { |
| FILE *cmdfile; |
| char *line; |
| |
| cmdfile = fopen(filename, "r"); |
| if (cmdfile == NULL) |
| fatalError(strerror(errno)); |
| |
| while ((line = get_line_from_file(cmdfile)) != NULL) { |
| line[strlen(line)-1] = 0; /* eat newline */ |
| add_cmd_str(line); |
| free(line); |
| } |
| } |
| |
| |
| static int do_sed_command(const struct sed_cmd *sed_cmd, const char *line) |
| { |
| int altered = 0; |
| |
| switch (sed_cmd->cmd) { |
| |
| case 'p': |
| fputs(line, stdout); |
| break; |
| |
| case 'd': |
| altered++; |
| break; |
| |
| case 's': /* oo, a fun one :-) */ |
| |
| /* we only substitute if the substitution 'search' expression matches */ |
| if (regexec(sed_cmd->sub_match, line, 0, NULL, 0) == 0) { |
| regmatch_t regmatch; |
| int i; |
| char *ptr = (char *)line; |
| |
| while (*ptr) { |
| /* if we can match the search string... */ |
| if (regexec(sed_cmd->sub_match, ptr, 1, ®match, 0) == 0) { |
| /* print everything before the match, */ |
| for (i = 0; i < regmatch.rm_so; i++) |
| fputc(ptr[i], stdout); |
| /* then print the substitution in its place */ |
| fputs(sed_cmd->replace, stdout); |
| /* then advance past the match */ |
| ptr += regmatch.rm_eo; |
| /* and let the calling function know that something |
| * has been changed */ |
| altered++; |
| |
| /* if we're not doing this globally... */ |
| if (!sed_cmd->sub_g) |
| break; |
| } |
| /* if we COULD NOT match the search string (meaning we've gone past |
| * all previous instances), get out */ |
| else |
| break; |
| } |
| |
| /* is there anything left to print? */ |
| if (*ptr) |
| fputs(ptr, stdout); |
| } |
| |
| break; |
| } |
| |
| return altered; |
| } |
| |
| static void process_file(FILE *file) |
| { |
| char *line = NULL; |
| static int linenum = 0; /* GNU sed does not restart counting lines at EOF */ |
| unsigned int still_in_range = 0; |
| int line_altered; |
| int i; |
| |
| /* go through every line in the file */ |
| while ((line = get_line_from_file(file)) != NULL) { |
| |
| linenum++; |
| line_altered = 0; |
| |
| /* for every line, go through all the commands */ |
| for (i = 0; i < ncmds; i++) { |
| |
| /* are we acting on a range of matched lines? */ |
| if (sed_cmds[i].beg_match && sed_cmds[i].end_match) { |
| if (still_in_range || regexec(sed_cmds[i].beg_match, line, 0, NULL, 0) == 0) { |
| line_altered += do_sed_command(&sed_cmds[i], line); |
| still_in_range = 1; |
| if (regexec(sed_cmds[i].end_match, line, 0, NULL, 0) == 0) |
| still_in_range = 0; |
| } |
| } |
| |
| /* are we trying to match a single line? */ |
| else if (sed_cmds[i].beg_match) { |
| if (regexec(sed_cmds[i].beg_match, line, 0, NULL, 0) == 0) |
| line_altered += do_sed_command(&sed_cmds[i], line); |
| } |
| |
| /* are we acting on a range of line numbers? */ |
| else if (sed_cmds[i].beg_line > 0 && sed_cmds[i].end_line > 0) { |
| if (linenum >= sed_cmds[i].beg_line && linenum <= sed_cmds[i].end_line) |
| line_altered += do_sed_command(&sed_cmds[i], line); |
| } |
| |
| /* are we acting on a specified line number */ |
| else if (sed_cmds[i].beg_line > 0) { |
| if (linenum == sed_cmds[i].beg_line) |
| line_altered += do_sed_command(&sed_cmds[i], line); |
| } |
| |
| /* not acting on matches or line numbers. act on every line */ |
| else |
| line_altered += do_sed_command(&sed_cmds[i], line); |
| |
| } |
| |
| /* we will print the line unless we were told to be quiet or if the |
| * line was altered (via a 'd'elete or 's'ubstitution) */ |
| if (!be_quiet && !line_altered) |
| fputs(line, stdout); |
| |
| free(line); |
| } |
| } |
| |
| extern int sed_main(int argc, char **argv) |
| { |
| int opt; |
| |
| /* do special-case option parsing */ |
| if (argv[1] && (strcmp(argv[1], "--help") == 0)) |
| usage(sed_usage); |
| |
| #if 0 |
| /* destroy command strings on exit */ |
| if (atexit(destroy_cmd_strs) == -1) { |
| perror("sed"); |
| exit(1); |
| } |
| #endif |
| |
| /* do normal option parsing */ |
| while ((opt = getopt(argc, argv, "Vhne:f:")) > 0) { |
| switch (opt) { |
| case 'V': |
| printf("Print Busybox version here\n"); |
| exit(0); |
| break; |
| case 'h': |
| usage(sed_usage); |
| break; |
| case 'n': |
| be_quiet++; |
| break; |
| case 'e': |
| add_cmd_str(optarg); |
| break; |
| case 'f': |
| load_cmd_file(optarg); |
| break; |
| } |
| } |
| |
| /* if we didn't get a pattern from a -e and no command file was specified, |
| * argv[optind] should be the pattern. no pattern, no worky */ |
| if (ncmds == 0) { |
| if (argv[optind] == NULL) |
| usage(sed_usage); |
| else { |
| add_cmd_str(argv[optind]); |
| optind++; |
| } |
| } |
| |
| |
| /* argv[(optind)..(argc-1)] should be names of file to process. If no |
| * files were specified or '-' was specified, take input from stdin. |
| * Otherwise, we process all the files specified. */ |
| if (argv[optind] == NULL || (strcmp(argv[optind], "-") == 0)) { |
| process_file(stdin); |
| } |
| else { |
| int i; |
| FILE *file; |
| for (i = optind; i < argc; i++) { |
| file = fopen(argv[i], "r"); |
| if (file == NULL) { |
| fprintf(stderr, "sed: %s: %s\n", argv[i], strerror(errno)); |
| } else { |
| process_file(file); |
| fclose(file); |
| } |
| } |
| } |
| |
| return 0; |
| } |