diff options
author | Mark Whitley <markw@lineo.com> | 2000-07-10 22:55:51 +0000 |
---|---|---|
committer | Mark Whitley <markw@lineo.com> | 2000-07-10 22:55:51 +0000 |
commit | 6315ce603b3ac2f4998e926b6106da21bcc0066f (patch) | |
tree | 0a3d57a74893ee848378e7f8f94e7167d30a063a /editors | |
parent | 85c552035e4c5199d1cbef6058eb365c6150f33d (diff) |
Brand, new sed that uses libc regex routines.
There is some common code used by both sed & grep that should be put into
utility.c as per Mat Kraai's suggestions/patch on the mailing list.
Specifically, a common regex_compile() and a regex_subst() function need to be
made.
Diffstat (limited to 'editors')
-rw-r--r-- | editors/sed.c | 763 |
1 files changed, 483 insertions, 280 deletions
diff --git a/editors/sed.c b/editors/sed.c index d4b721e49..329f5ae8d 100644 --- a/editors/sed.c +++ b/editors/sed.c @@ -1,15 +1,8 @@ -/* vi: set sw=4 ts=4: */ /* - * Mini sed implementation for busybox - * + * sed.c - very minimalist version of sed * * Copyright (C) 1999,2000 by Lineo, inc. - * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org> - * - * Modifications for addresses and append command have been - * written by Marco Pantaleoni <panta@prosa.it>, <panta@elasticworld.org> - * and are: - * Copyright (C) 1999 Marco Pantaleoni. + * 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 @@ -27,333 +20,543 @@ * */ -#include "internal.h" -#include "regexp.h" +/* + 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 <dirent.h> +#include <stdlib.h> /* for realloc() */ +#include <unistd.h> /* for getopt() */ +#include <regex.h> +#include <string.h> /* for strdup() */ #include <errno.h> -#include <fcntl.h> -#include <signal.h> -#include <time.h> -#include <ctype.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 [-n] -e script [file...]\n" + "sed [-Vhnef] pattern [files...]\n" #ifndef BB_FEATURE_TRIVIAL_HELP - "\nAllowed sed scripts come in the following form:\n" - "\t'ADDR [!] COMMAND'\n\n" - "\twhere address ADDR can be:\n" - "\t NUMBER Match specified line number\n" - "\t $ Match last line\n" - "\t /REGEXP/ Match specified regexp\n" - "\t (! inverts the meaning of the match)\n\n" - "\tand COMMAND can be:\n" - "\t s/regexp/replacement/[igp]\n" - "\t which attempt to match regexp against the pattern space\n" - "\t and if successful replaces the matched portion with replacement.\n\n" - "\t aTEXT\n" - "\t which appends TEXT after the pattern space\n" - "Options:\n" - "-e\tadd the script to the commands to be executed\n" - "-n\tsuppress automatic printing of pattern space\n\n" -#if defined BB_REGEXP - "This version of sed matches full regular expressions.\n"; -#else - "This version of sed matches strings (not full regular expressions).\n" -#endif + "\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 ; -/* Flags & variables */ +#if 0 +/* Nuke from here { */ -typedef enum { f_none, f_replace, f_append } sed_function; -#define NO_LINE -2 -#define LAST_LINE -1 -static int addr_line = NO_LINE; -static char *addr_pattern = NULL; -static int negated = 0; +/* get_line_from_file() - This function reads an entire line from a text file + * * up to a newline. It returns a malloc'ed char * which must be stored and + * * free'ed by the caller. */ +extern char *get_line_from_file(FILE *file) +{ + static const int GROWBY = 80; /* how large we will grow strings by */ -#define SKIPSPACES(p) do { while (isspace(*(p))) (p)++; } while (0) + int ch; + int idx = 0; + char *linebuf = NULL; + int linebufsz = 0; -#define BUFSIZE 1024 + while (1) { + ch = fgetc(file); + if (ch == EOF) + break; + /* grow the line buffer as necessary */ + if (idx > linebufsz-2) + linebuf = realloc(linebuf, linebufsz += GROWBY); + linebuf[idx++] = (char)ch; + if ((char)ch == '\n') + break; + } + + if (idx == 0) + return NULL; + + linebuf[idx] = 0; + return linebuf; +} -static inline int at_last(FILE * fp) +static void usage(const char *string) { - int res = 0; + printf("usage: %s\n", string); + exit(0); +} - if (feof(fp)) - return 1; - else { - int ch; +/* } to here when we integrate this into busybox */ +#endif + +static void destroy_cmd_strs() +{ + if (sed_cmds == NULL) + return; + + /* destroy all the elements in the array */ + while (--ncmds >= 0) { - if ((ch = fgetc(fp)) == EOF) - res++; - ungetc(ch, fp); + 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); } - return res; + + /* destroy the array */ + free(sed_cmds); + sed_cmds = NULL; +} + +static void exit_sed(int retcode, const char *message) +{ + destroy_cmd_strs(); + if (message) + fputs(message, stderr); + exit(retcode); } -static void do_sed_repl(FILE * fp, char *needle, char *newNeedle, - int ignoreCase, int printFlag, int quietFlag) +/* + * 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) { - int foundOne = FALSE; - char haystack[BUFSIZE]; - int line = 1, doit; - - while (fgets(haystack, BUFSIZE - 1, fp)) { - doit = 0; - if (addr_pattern) { - doit = !find_match(haystack, addr_pattern, FALSE); - } else if (addr_line == NO_LINE) - doit = 1; - else if (addr_line == LAST_LINE) { - if (at_last(fp)) - doit = 1; - } else { - if (line == addr_line) - doit = 1; + 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] == '/') { + int ret; + idx = index_of_next_unescaped_slash(idx, my_str); + if (idx == -1) { + free(my_str); + exit_sed(1, "sed: unterminated match expression\n"); } - if (negated) - doit = 1 - doit; - if (doit) { - foundOne = - replace_match(haystack, needle, newNeedle, ignoreCase); - - if (foundOne == TRUE && printFlag == TRUE) { - fprintf(stdout, haystack); + my_str[idx] = 0; /* shave off the trailing '/' */ + my_str++; /* shave off the leading '/' */ + *regex = (regex_t *)malloc(sizeof(regex_t)); + if ((ret = regcomp(*regex, my_str, 0)) != 0) { + /* error handling if regular expression couldn't be compiled */ + int errmsgsz = regerror(ret, *regex, NULL, 0); + char *errmsg = malloc(errmsgsz); + if (errmsg == NULL) { + exit_sed(1, "sed: memory error\n"); } + regerror(ret, *regex, errmsg, errmsgsz); + fprintf(stderr, "sed: %s\n", errmsg); + free(errmsg); + exit_sed(1, NULL); } + my_str--; /* move my_str back so free() (below) won't barf */ + idx++; /* advance idx one past the end of the /match/ */ + } + 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; + } - if (quietFlag == FALSE) { - fprintf(stdout, haystack); - } + free(my_str); + return idx; +} - line++; +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') + exit_sed(1, "sed: missing command\n"); + if (!strchr("pds", cmdstr[idx])) /* <-- XXX add new commands here */ + exit_sed(1, "sed: invalid command\n"); + sed_cmd->cmd = cmdstr[idx]; + /* special-case handling for 's' */ + if (sed_cmd->cmd == 's') { + int oldidx; + /* format for substitution is: + * s/match/replace/g + * | | + * mandatory optional + */ + + /* verify that we have an 's' followed by a 'slash' */ + if (cmdstr[++idx] != '/') + exit_sed(1, "sed: bad format in substitution expression\n"); + + /* get the substitution part */ + idx += get_address(&cmdstr[idx], NULL, &sed_cmd->sub_match); + + /* get the replacement part */ + oldidx = idx; + idx = index_of_next_unescaped_slash(idx, cmdstr); + sed_cmd->replace = (char *)malloc(idx - oldidx + 1); + strncpy(sed_cmd->replace, &cmdstr[oldidx], idx - oldidx); + sed_cmd->replace[idx - oldidx] = 0; + + /* store the 'g' if present */ + if (cmdstr[++idx] == 'g') + sed_cmd->sub_g = 1; } } -static void do_sed_append(FILE * fp, char *appendline, int quietFlag) +static void add_cmd_str(const char *cmdstr) { - char buffer[BUFSIZE]; - int line = 1, doit; - - while (fgets(buffer, BUFSIZE - 1, fp)) { - doit = 0; - if (addr_pattern) { - doit = !find_match(buffer, addr_pattern, FALSE); - } else if (addr_line == NO_LINE) - doit = 1; - else if (addr_line == LAST_LINE) { - if (at_last(fp)) - doit = 1; - } else { - if (line == addr_line) - doit = 1; - } - if (negated) - doit = 1 - doit; - if (quietFlag == FALSE) { - fprintf(stdout, buffer); - } - if (doit) { - fputs(appendline, stdout); - fputc('\n', stdout); - } + char *my_cmdstr = trim_str(cmdstr); - line++; + /* 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); } -extern int sed_main(int argc, char **argv) + +static void load_cmd_file(char *filename) { - FILE *fp; - char *needle = NULL, *newNeedle = NULL; - char *name; - char *cp; - int ignoreCase = FALSE; - int printFlag = FALSE; - int quietFlag = FALSE; - int stopNow; - char *line_s = NULL, saved; - char *appendline = NULL; - char *pos; - sed_function sed_f = f_none; - - argc--; - argv++; - if (argc < 1) { - usage(sed_usage); + FILE *cmdfile; + char *line; + + cmdfile = fopen(filename, "r"); + if (cmdfile == NULL) + exit_sed(1, strerror(errno)); + + while ((line = get_line_from_file(cmdfile)) != NULL) { + line[strlen(line)-1] = 0; /* eat newline */ + add_cmd_str(line); + free(line); } +} - while (argc > 1) { - if (**argv != '-') - usage(sed_usage); - argc--; - cp = *argv++; - stopNow = FALSE; - while (*++cp && stopNow == FALSE) { - switch (*cp) { - case 'n': - quietFlag = TRUE; - break; - case 'e': - if (*(cp + 1) == 0 && --argc < 0) { - usage(sed_usage); - } - if (*++cp != 's') - cp = *argv++; - - /* Read address if present */ - SKIPSPACES(cp); - if (*cp == '$') { - addr_line = LAST_LINE; - cp++; - } else { - if (isdigit(*cp)) { /* LINE ADDRESS */ - line_s = cp; - while (isdigit(*cp)) - cp++; - if (cp > line_s) { - /* numeric line */ - saved = *cp; - *cp = '\0'; - addr_line = atoi(line_s); - *cp = saved; - } - } else if (*cp == '/') { /* PATTERN ADDRESS */ - pos = addr_pattern = cp + 1; - pos = strchr(pos, '/'); - if (!pos) - usage(sed_usage); - *pos = '\0'; - cp = pos + 1; - } - } +static int do_sed_command(const struct sed_cmd *sed_cmd, const char *line) +{ + int altered = 0; - SKIPSPACES(cp); - if (*cp == '!') { - negated++; - cp++; - } + switch (sed_cmd->cmd) { - /* Read command */ + case 'p': + fputs(line, stdout); + break; - SKIPSPACES(cp); - switch (*cp) { - case 's': /* REPLACE */ - if (strlen(cp) <= 3 || *(cp + 1) != '/') - break; - sed_f = f_replace; - - pos = needle = cp + 2; - - for (;;) { - pos = strchr(pos, '/'); - if (pos == NULL) { - usage(sed_usage); - } - if (*(pos - 1) == '\\') { - pos++; - continue; - } - 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; } - *pos = 0; - newNeedle = ++pos; - for (;;) { - pos = strchr(pos, '/'); - if (pos == NULL) { - usage(sed_usage); - } - if (*(pos - 1) == '\\') { - pos++; - continue; - } + /* if we COULD NOT match the search string (meaning we've gone past + * all previous instances), get out */ + else break; - } - *pos = 0; - if (pos + 2 != 0) { - while (*++pos) { - switch (*pos) { - case 'i': - ignoreCase = TRUE; - break; - case 'p': - printFlag = TRUE; - break; - case 'g': - break; - default: - usage(sed_usage); - } - } - } - cp = pos; - /* fprintf(stderr, "replace '%s' with '%s'\n", needle, newNeedle); */ - break; + } - case 'a': /* APPEND */ - if (strlen(cp) < 2) - break; - sed_f = f_append; - appendline = ++cp; - /* fprintf(stderr, "append '%s'\n", appendline); */ - 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; } + } - stopNow = TRUE; - break; + /* 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); + } - default: - usage(sed_usage); + /* 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); } - } - } - if (argc == 0) { - switch (sed_f) { - case f_none: - break; - case f_replace: - do_sed_repl(stdin, needle, newNeedle, ignoreCase, printFlag, - quietFlag); - break; - case f_append: - do_sed_append(stdin, appendline, quietFlag); - break; - } - } else { - while (argc-- > 0) { - name = *argv++; - - fp = fopen(name, "r"); - if (fp == NULL) { - perror(name); - continue; + /* 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); } - switch (sed_f) { - case f_none: + /* 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); + + /* 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 f_replace: - do_sed_repl(fp, needle, newNeedle, ignoreCase, printFlag, - quietFlag); + case 'h': + usage(sed_usage); break; - case f_append: - do_sed_append(fp, appendline, quietFlag); + 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++; + } + } - if (ferror(fp)) - perror(name); - fclose(fp); + /* 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(TRUE); -} + + exit_sed(0, NULL); + /* not reached */ + return 0; +} -/* END CODE */ +#ifdef TEST_SED +int main(int argc, char **argv) +{ + return sed_main(argc, argv); +} +#endif |