X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=sed.c;h=897c290d5cf73ce6b23420ab856ebe798787aad4;hb=4fd382ea29c6492f4776aa29b8b298d3c4a98d01;hp=1f1e9069cc92fa6da36b5eab1d6a2288a92d1d4e;hpb=464c5de00d3dfb5f01e866f703d95bbb2bb9443c;p=oweals%2Fbusybox.git diff --git a/sed.c b/sed.c index 1f1e9069c..897c290d5 100644 --- a/sed.c +++ b/sed.c @@ -1,8 +1,8 @@ /* * sed.c - very minimalist version of sed * - * Copyright (C) 1999,2000 by Lineo, inc. - * Written by Mark Whitley , + * Copyright (C) 1999,2000,2001 by Lineo, inc. + * Written by Mark Whitley , * * 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 @@ -27,6 +27,7 @@ - address matching: num|/matchstr/[,num|/matchstr/|$]command - commands: (p)rint, (d)elete, (s)ubstitue (with g & I flags) - edit commands: (a)ppend, (i)nsert, (c)hange + - backreferences in substitution expressions (\1, \2...\9) (Note: Specifying an address (range) to match is *optional*; commands default to the whole pattern space if no specific address match was @@ -35,32 +36,35 @@ 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 -#include /* for realloc() */ #include /* for getopt() */ #include #include /* for strdup() */ #include #include /* for isspace() */ -#include "internal.h" - +#include +#include "busybox.h" /* externs */ +extern void xregcomp(regex_t *preg, const char *regex, int cflags); extern int optind; /* in unistd.h */ extern char *optarg; /* ditto */ /* options */ static int be_quiet = 0; + struct sed_cmd { + + /* GENERAL FIELDS */ + char delimiter; /* The delimiter used to separate regexps */ + /* 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 == $ */ @@ -70,12 +74,21 @@ struct sed_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? */ + + /* SUBSTITUTION COMMAND SPECIFIC FIELDS */ + + /* sed -e 's/sub_match/replace/' */ + regex_t *sub_match; + char *replace; + unsigned int num_backrefs:4; /* how many back references (\1..\9) */ + /* Note: GNU/POSIX sed does not save more than nine backrefs, so + * we only use 4 bits to hold the number */ unsigned int sub_g:1; /* sed -e 's/foo/bar/g' (global) */ + unsigned int sub_p:2; /* sed -e 's/foo/bar/p' (print substitution) */ + + + /* EDIT COMMAND (a,i,c) SPEICIFIC FIELDS */ - /* edit command (a,i,c) speicific field */ char *editline; }; @@ -85,23 +98,7 @@ 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 +#ifdef BB_FEATURE_CLEAN_UP static void destroy_cmd_strs() { if (sed_cmds == NULL) @@ -132,78 +129,34 @@ static void destroy_cmd_strs() } #endif -#if 0 -/* - * 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. - * XXX: This is now obsolete. Maybe it belongs nowhere. - */ -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[strrspn(retstr, " \n\t\v") + 1] = 0; - */ - - return retstr; -} -#endif - -#if 0 -/* - * strrspn - works just like strspn() but goes from right to left instead of - * left to right - */ -static size_t strrspn(const char *s, const char *accept) -{ - size_t i = strlen(s); - - while (strchr(accept, s[--i])) - ; - - return i; -} -#endif /* - * 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. + * index_of_next_unescaped_regexp_delim - walks left to right through a string + * beginning at a specified index and returns the index of the next regular + * expression delimiter (typically a forward * slash ('/')) not preceeded by + * a backslash ('\'). */ -static int index_of_next_unescaped_slash(const char *str, int idx) +static int index_of_next_unescaped_regexp_delim(struct sed_cmd *sed_cmd, const char *str, int idx) { - do { - idx++; - /* test if we've hit the end */ - if (str[idx] == 0) - return -1; - } while (str[idx] != '/' && str[idx - 1] != '\\'); + for ( ; str[idx]; idx++) { + if (str[idx] == sed_cmd->delimiter && str[idx-1] != '\\') + return idx; + } - return idx; + /* if we make it to here, we've hit the end of the string */ + return -1; } /* * returns the index in the string just past where the address ends. */ -static int get_address(const char *str, int *line, regex_t **regex) +static int get_address(struct sed_cmd *sed_cmd, const char *str, int *line, regex_t **regex) { char *my_str = strdup(str); int idx = 0; + char olddelimiter; + olddelimiter = sed_cmd->delimiter; + sed_cmd->delimiter = '/'; if (isdigit(my_str[idx])) { do { @@ -217,21 +170,22 @@ static int get_address(const char *str, int *line, regex_t **regex) idx++; } else if (my_str[idx] == '/') { - idx = index_of_next_unescaped_slash(my_str, idx); + idx = index_of_next_unescaped_regexp_delim(sed_cmd, my_str, ++idx); if (idx == -1) - fatalError("unterminated match expression\n"); + error_msg_and_die("unterminated match expression"); my_str[idx] = '\0'; *regex = (regex_t *)xmalloc(sizeof(regex_t)); - xregcomp(*regex, my_str+1, REG_NEWLINE); + xregcomp(*regex, my_str+1, 0); idx++; /* so it points to the next character after the last '/' */ } else { - errorMsg("get_address: no address found in string\n" - "\t(you probably didn't check the string you passed me)\n"); + error_msg("get_address: no address found in string\n" + "\t(you probably didn't check the string you passed me)"); idx = -1; } free(my_str); + sed_cmd->delimiter = olddelimiter; return idx; } @@ -249,32 +203,48 @@ static int parse_subst_cmd(struct sed_cmd *sed_cmd, const char *substr) int oldidx, cflags = REG_NEWLINE; char *match; int idx = 0; + int j; /* * the string that gets passed to this function should look like this: - * s/match/replace/gI - * || | || + * s/match/replace/gIp + * || | ||| * mandatory optional * * (all three of the '/' slashes are mandatory) */ - /* verify that the 's' is followed by a 'slash' */ - if (substr[++idx] != '/') - fatalError("bad format in substitution expression\n"); + /* verify that the 's' is followed by something. That something + * (typically a 'slash') is now our regexp delimiter... */ + if (!substr[++idx]) + error_msg_and_die("bad format in substitution expression"); + else + sed_cmd->delimiter=substr[idx]; /* save the match string */ oldidx = idx+1; - idx = index_of_next_unescaped_slash(substr, idx); + idx = index_of_next_unescaped_regexp_delim(sed_cmd, substr, ++idx); if (idx == -1) - fatalError("bad format in substitution expression\n"); + error_msg_and_die("bad format in substitution expression"); match = strdup_substr(substr, oldidx, idx); + /* determine the number of back references in the match string */ + /* Note: we compute this here rather than in the do_subst_command() + * function to save processor time, at the expense of a little more memory + * (4 bits) per sed_cmd */ + + /* sed_cmd->num_backrefs = 0; */ /* XXX: not needed? --apparently not */ + for (j = 0; match[j]; j++) { + /* GNU/POSIX sed does not save more than nine backrefs */ + if (match[j] == '\\' && match[j+1] == '(' && sed_cmd->num_backrefs <= 9) + sed_cmd->num_backrefs++; + } + /* save the replacement string */ oldidx = idx+1; - idx = index_of_next_unescaped_slash(substr, idx); + idx = index_of_next_unescaped_regexp_delim(sed_cmd, substr, ++idx); if (idx == -1) - fatalError("bad format in substitution expression\n"); + error_msg_and_die("bad format in substitution expression"); sed_cmd->replace = strdup_substr(substr, oldidx, idx); /* process the flags */ @@ -286,17 +256,20 @@ static int parse_subst_cmd(struct sed_cmd *sed_cmd, const char *substr) case 'I': cflags |= REG_ICASE; break; + case 'p': + sed_cmd->sub_p = 1; + break; default: /* any whitespace or semicolon trailing after a s/// is ok */ if (strchr("; \t\v\n\r", substr[idx])) goto out; /* else */ - fatalError("bad option in substitution expression\n"); + error_msg_and_die("bad option in substitution expression"); } } out: - /* compile the regex */ + /* compile the match string into a regex */ sed_cmd->sub_match = (regex_t *)xmalloc(sizeof(regex_t)); xregcomp(sed_cmd->sub_match, match, cflags); free(match); @@ -333,7 +306,7 @@ static int parse_edit_cmd(struct sed_cmd *sed_cmd, const char *editstr) */ if (editstr[1] != '\\' && (editstr[2] != '\n' || editstr[2] != '\r')) - fatalError("bad format in edit expression\n"); + error_msg_and_die("bad format in edit expression"); /* store the edit line text */ /* make editline big enough to accomodate the extra '\n' we will tack on @@ -389,17 +362,17 @@ static char *parse_cmd_str(struct sed_cmd *sed_cmd, const char *cmdstr) /* 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); + idx = get_address(sed_cmd, 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); + idx += get_address(sed_cmd, &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"); + error_msg_and_die("missing command"); if (!strchr("pdsaic", cmdstr[idx])) /* <-- XXX add new commands here */ - fatalError("invalid command\n"); + error_msg_and_die("invalid command"); sed_cmd->cmd = cmdstr[idx]; /* special-case handling for (s)ubstitution */ @@ -409,7 +382,7 @@ static char *parse_cmd_str(struct sed_cmd *sed_cmd, const char *cmdstr) /* special-case handling for (a)ppend, (i)nsert, and (c)hange */ else if (strchr("aic", cmdstr[idx])) { if (sed_cmd->end_line || sed_cmd->end_match) - fatalError("only a beginning address can be specified for edit commands\n"); + error_msg_and_die("only a beginning address can be specified for edit commands"); idx += parse_edit_cmd(sed_cmd, &cmdstr[idx]); } /* if it was a single-letter command (such as 'p' or 'd') we need to @@ -439,7 +412,7 @@ static void add_cmd_str(const char *cmdstr) continue; } /* grow the array */ - sed_cmds = realloc(sed_cmds, sizeof(struct sed_cmd) * (++ncmds)); + sed_cmds = xrealloc(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, get remainder */ @@ -455,65 +428,108 @@ static void load_cmd_file(char *filename) char *line; char *nextline; - cmdfile = fopen(filename, "r"); - if (cmdfile == NULL) - fatalError(strerror(errno)); + cmdfile = xfopen(filename, "r"); while ((line = get_line_from_file(cmdfile)) != NULL) { /* if a line ends with '\' it needs the next line appended to it */ while (line[strlen(line)-2] == '\\' && (nextline = get_line_from_file(cmdfile)) != NULL) { - line = realloc(line, strlen(line) + strlen(nextline) + 1); + line = xrealloc(line, strlen(line) + strlen(nextline) + 1); strcat(line, nextline); free(nextline); } /* eat trailing newline (if any) --if I don't do this, edit commands * (aic) will print an extra newline */ - if (line[strlen(line)-1] == '\n') - line[strlen(line)-1] = 0; + chomp(line); add_cmd_str(line); free(line); } } +static void print_subst_w_backrefs(const char *line, const char *replace, regmatch_t *regmatch) +{ + int i; + + /* go through the replacement string */ + for (i = 0; replace[i]; i++) { + /* if we find a backreference (\1, \2, etc.) print the backref'ed * text */ + if (replace[i] == '\\' && isdigit(replace[i+1])) { + int j; + char tmpstr[2]; + int backref; + ++i; /* i now indexes the backref number, instead of the leading slash */ + tmpstr[0] = replace[i]; + tmpstr[1] = 0; + backref = atoi(tmpstr); + /* print out the text held in regmatch[backref] */ + for (j = regmatch[backref].rm_so; j < regmatch[backref].rm_eo; j++) + fputc(line[j], stdout); + } + + /* if we find a backslash escaped character, print the character */ + else if (replace[i] == '\\') { + ++i; + fputc(replace[i], stdout); + } + + /* if we find an unescaped '&' print out the whole matched text. + * fortunately, regmatch[0] contains the indicies to the whole matched + * expression (kinda seems like it was designed for just such a + * purpose...) */ + else if (replace[i] == '&' && replace[i-1] != '\\') { + int j; + for (j = regmatch[0].rm_so; j < regmatch[0].rm_eo; j++) + fputc(line[j], stdout); + } + /* nothing special, just print this char of the replacement string to stdout */ + else + fputc(replace[i], stdout); + } +} + static int do_subst_command(const struct sed_cmd *sed_cmd, const char *line) { + char *hackline = (char *)line; int altered = 0; + regmatch_t *regmatch = NULL; + + /* we only proceed if the substitution 'search' expression matches */ + if (regexec(sed_cmd->sub_match, line, 0, NULL, 0) == REG_NOMATCH) + return 0; - /* we only substitute if the substitution 'search' expression matches */ - if (regexec(sed_cmd->sub_match, line, 0, NULL, 0) == 0) { - regmatch_t regmatch; + /* whaddaya know, it matched. get the number of back references */ + regmatch = xmalloc(sizeof(regmatch_t) * (sed_cmd->num_backrefs+1)); + + /* and now, as long as we've got a line to try matching and if we can match + * the search string, we make substitutions */ + while (*hackline && (regexec(sed_cmd->sub_match, hackline, + sed_cmd->num_backrefs+1, regmatch, 0) == 0) ) { 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 flag that something has 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); + /* print everything before the match */ + for (i = 0; i < regmatch[0].rm_so; i++) + fputc(hackline[i], stdout); + + /* then print the substitution string */ + print_subst_w_backrefs(hackline, sed_cmd->replace, regmatch); + + /* advance past the match */ + hackline += regmatch[0].rm_eo; + /* flag that something has changed */ + altered++; + + /* if we're not doing this globally, get out now */ + if (!sed_cmd->sub_g) + break; } + /* if there's anything left of the line, print it */ + if (*hackline) + fputs(hackline, stdout); + + /* cleanup */ + free(regmatch); + return altered; } @@ -532,7 +548,38 @@ static int do_sed_command(const struct sed_cmd *sed_cmd, const char *line) break; case 's': - altered = do_subst_command(sed_cmd, line); + + /* + * Some special cases for 's' printing to make it compliant with + * GNU sed printing behavior (aka "The -n | s///p Matrix"): + * + * -n ONLY = never print anything regardless of any successful + * substitution + * + * s///p ONLY = always print successful substitutions, even if + * the line is going to be printed anyway (line will be printed + * twice). + * + * -n AND s///p = print ONLY a successful substitution ONE TIME; + * no other lines are printed - this is the reason why the 'p' + * flag exists in the first place. + */ + + /* if the user specified that they didn't want anything printed (i.e. a -n + * flag and no 'p' flag after the s///), then there's really no point doing + * anything here. */ + if (be_quiet && !sed_cmd->sub_p) + break; + + /* we print the line once, unless we were told to be quiet */ + if (!be_quiet) + altered = do_subst_command(sed_cmd, line); + + /* we also print the line if we were given the 'p' flag + * (this is quite possibly the second printing) */ + if (sed_cmd->sub_p) + altered = do_subst_command(sed_cmd, line); + break; case 'a': @@ -575,9 +622,10 @@ static void process_file(FILE *file) 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) + if (still_in_range && regexec(sed_cmds[i].end_match, line, 0, NULL, 0) == 0) still_in_range = 0; + else + still_in_range = 1; } } @@ -588,8 +636,9 @@ static void process_file(FILE *file) } /* 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) + else if (sed_cmds[i].beg_line > 0 && sed_cmds[i].end_line != 0) { + if (linenum >= sed_cmds[i].beg_line && + (sed_cmds[i].end_line == -1 || linenum <= sed_cmds[i].end_line)) line_altered += do_sed_command(&sed_cmds[i], line); } @@ -606,7 +655,8 @@ static void process_file(FILE *file) } /* 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) */ + * line was altered (via a 'd'elete or 's'ubstitution), in which case + * the altered line was already printed */ if (!be_quiet && !line_altered) fputs(line, stdout); @@ -618,28 +668,15 @@ 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 +#ifdef BB_FEATURE_CLEAN_UP /* destroy command strings on exit */ - if (atexit(destroy_cmd_strs) == -1) { - perror("sed"); - exit(1); - } + if (atexit(destroy_cmd_strs) == -1) + perror_msg_and_die("atexit"); #endif /* do normal option parsing */ - while ((opt = getopt(argc, argv, "Vhne:f:")) > 0) { + while ((opt = getopt(argc, argv, "ne:f:")) > 0) { switch (opt) { - case 'V': - printf("BusyBox v%s (%s)\n", BB_VER, BB_BT); - exit(0); - break; - case 'h': - usage(sed_usage); - break; case 'n': be_quiet++; break; @@ -649,6 +686,8 @@ extern int sed_main(int argc, char **argv) case 'f': load_cmd_file(optarg); break; + default: + show_usage(); } } @@ -656,7 +695,7 @@ extern int sed_main(int argc, char **argv) * argv[optind] should be the pattern. no pattern, no worky */ if (ncmds == 0) { if (argv[optind] == NULL) - usage(sed_usage); + show_usage(); else { add_cmd_str(argv[optind]); optind++; @@ -676,7 +715,7 @@ extern int sed_main(int argc, char **argv) for (i = optind; i < argc; i++) { file = fopen(argv[i], "r"); if (file == NULL) { - errorMsg("%s: %s\n", argv[i], strerror(errno)); + perror_msg("%s", argv[i]); } else { process_file(file); fclose(file);