1 /* grep.c - print lines what match given regular expression
3 * Copyright 2013 CE Strake <strake888 at gmail.com>
5 * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/grep.html
9 USE_GREP(NEWTOY(grep, "C#B#A#ZzEFHabhinorsvwclqe*f*m#x[!wx][!EFw]", TOYFLAG_BIN))
10 USE_EGREP(OLDTOY(egrep, grep, TOYFLAG_BIN))
11 USE_FGREP(OLDTOY(fgrep, grep, TOYFLAG_BIN))
17 usage: grep [-EFivwcloqsHbhn] [-A NUM] [-m MAX] [-e REGEX]... [-f REGFILE] [FILE]...
19 Show lines matching regular expressions. If no -e, first argument is
20 regular expression to match. With no files (or "-" filename) read stdin.
21 Returns 0 if matched, 1 if no match found.
23 -e Regex to match. (May be repeated.)
24 -f File containing regular expressions to match.
27 -A Show NUM lines after -B Show NUM lines before match
28 -C NUM lines context (A+B) -E extended regex syntax
29 -F fixed (literal match) -i case insensitive
30 -m match MAX many lines -r recursive (on dir)
31 -v invert match -w whole word (implies -E)
32 -x whole line -z input NUL terminated
34 display modes: (default: matched line)
35 -c count of matching lines -l show matching filenames
36 -o only matching part -q quiet (errors only)
37 -s silent (no error msg) -Z output NUL terminated
39 output prefix (default: filename if checking more than 1 file)
40 -H force filename -b byte offset of match
41 -h hide filename -n line number of match
67 // Show matches in one file
68 static void do_grep(int fd, char *name)
70 struct double_list *dlb = 0;
71 FILE *file = fdopen(fd, "r");
72 long offset = 0, after = 0, before = 0;
73 int lcount = 0, mcount = 0;
74 char *bars = 0, indelim = '\n' * !(toys.optflags&FLAG_z),
75 outdelim = '\n' * !(toys.optflags&FLAG_Z);
77 if (!fd) name = "(standard input)";
84 // Loop through lines of input
86 char *line = 0, *start;
93 if (0 > (len = getdelim(&line, &unused, indelim, file))) break;
94 if (line[len-1] == indelim) line[len-1] = 0;
98 // Loop through matches in this line
100 int rc = 0, skip = 0;
102 // Handle non-regex matches
103 if (toys.optflags & FLAG_F) {
104 struct arg_list *seek, fseek;
107 for (seek = TT.e; seek; seek = seek->next) {
108 if (toys.optflags & FLAG_x) {
109 int i = (toys.optflags & FLAG_i);
111 if ((i ? strcasecmp : strcmp)(seek->arg, line)) s = line;
112 } else if (!*seek->arg) {
114 fseek.arg = s = line;
117 if (toys.optflags & FLAG_i) {
118 long ll = strlen(seek->arg);;
120 // Alas, posix hasn't got strcasestr()
121 for (s = line; *s; s++) if (!strncasecmp(s, seek->arg, ll)) break;
123 } else s = strstr(line, seek->arg);
128 matches.rm_so = (s-line);
129 skip = matches.rm_eo = (s-line)+strlen(seek->arg);
132 rc = regexec((regex_t *)toybuf, start, 1, &matches,
133 start==line ? 0 : REG_NOTBOL);
134 skip = matches.rm_eo;
137 if (toys.optflags & FLAG_x)
138 if (matches.rm_so || line[matches.rm_eo]) rc = 1;
140 if (!rc && (toys.optflags & FLAG_w)) {
143 if ((start+matches.rm_so)!=line) {
144 c = start[matches.rm_so-1];
145 if (!isalnum(c) && c != '_') c = 0;
148 c = start[matches.rm_eo];
149 if (!isalnum(c) && c != '_') c = 0;
152 start += matches.rm_so+1;
158 if (toys.optflags & FLAG_v) {
159 if (toys.optflags & FLAG_o) {
160 if (rc) skip = matches.rm_eo = strlen(start);
161 else if (!matches.rm_so) {
164 } else matches.rm_eo = matches.rm_so;
167 matches.rm_eo = strlen(start);
170 } else if (rc) break;
172 // At least one line we didn't print since match while -ABC active
179 if (toys.optflags & FLAG_q) xexit();
180 if (toys.optflags & FLAG_l) {
181 printf("%s%c", name, outdelim);
186 if (toys.optflags & FLAG_o)
187 if (matches.rm_eo == matches.rm_so)
190 if (!(toys.optflags & FLAG_c)) {
191 if (toys.optflags & FLAG_H) printf("%s:", name);
192 if (toys.optflags & FLAG_n) printf("%d:", lcount);
193 if (toys.optflags & FLAG_b)
194 printf("%ld:", offset + (start-line) +
195 ((toys.optflags & FLAG_o) ? matches.rm_so : 0));
196 if (!(toys.optflags & FLAG_o)) {
198 struct double_list *dl = dlist_pop(&dlb);
200 xprintf("%s%c", dl->data, outdelim);
206 while (before) xprintf("%s%c", line, outdelim);
207 xprintf("%s%c", line, outdelim);
208 if (TT.a) after = TT.a+1;
210 xprintf("%.*s%c", (int)(matches.rm_eo-matches.rm_so),
211 start+matches.rm_so, outdelim);
216 if (!(toys.optflags & FLAG_o)) break;
220 if (mmatch) mcount++;
222 int discard = (after || TT.b);
224 if (after && --after) {
225 xprintf("%s%c", line, outdelim);
228 if (discard && TT.b) {
229 dlist_add(&dlb, line);
232 struct double_list *dl;
234 dl = dlist_pop(&dlb);
240 if (discard && mcount) bars = "--";
244 if ((toys.optflags & FLAG_m) && mcount >= TT.m) break;
247 if (toys.optflags & FLAG_c) {
248 if (toys.optflags & FLAG_H) printf("%s:", name);
249 xprintf("%d%c", mcount, outdelim);
252 // loopfiles will also close the fd, but this frees an (opaque) struct.
256 static void parse_regex(void)
258 struct arg_list *al, *new, *list = NULL;
262 // Add all -f lines to -e list. (Yes, this is leaking allocation context for
263 // exit to free. Not supporting nofork for this command any time soon.)
264 al = TT.f ? TT.f : TT.e;
266 if (TT.f) s = ss = xreadfile(al->arg, 0, 0);
267 else s = ss = al->arg;
269 // Split lines at \n, add individual lines to new list.
271 ss = strchr(s, '\n');
273 new = xmalloc(sizeof(struct arg_list));
280 // Advance, when we run out of -f switch to -e.
289 if (!(toys.optflags & FLAG_F)) {
293 // Convert strings to one big regex
294 for (al = TT.e; al; al = al->next)
295 len += strlen(al->arg)+1+!(toys.optflags & FLAG_E);
297 regstr = s = xmalloc(len);
298 for (al = TT.e; al; al = al->next) {
299 s = stpcpy(s, al->arg);
300 if (!(toys.optflags & FLAG_E)) *(s++) = '\\';
303 *(s-=(1+!(toys.optflags & FLAG_E))) = 0;
305 i = regcomp((regex_t *)toybuf, regstr,
306 ((toys.optflags & FLAG_E) ? REG_EXTENDED : 0) |
307 ((toys.optflags & FLAG_i) ? REG_ICASE : 0));
310 regerror(i, (regex_t *)toybuf, toybuf+sizeof(regex_t),
311 sizeof(toybuf)-sizeof(regex_t));
312 error_exit("bad REGEX: %s", toybuf);
317 static int do_grep_r(struct dirtree *new)
321 if (new->parent && !dirtree_notdotdot(new)) return 0;
322 if (S_ISDIR(new->st.st_mode)) return DIRTREE_RECURSE;
324 // "grep -r onefile" doesn't show filenames, but "grep -r onedir" should.
325 if (new->parent && !(toys.optflags & FLAG_h)) toys.optflags |= FLAG_H;
327 name = dirtree_path(new, 0);
328 do_grep(openat(dirtree_parentfd(new), new->name, 0), name);
336 char **ss = toys.optargs;
338 if (!TT.a) TT.a = TT.c;
339 if (!TT.b) TT.b = TT.c;
341 // Handle egrep and fgrep
342 if (*toys.which->name == 'e') toys.optflags |= FLAG_E;
343 if (*toys.which->name == 'f') toys.optflags |= FLAG_F;
345 if (!TT.e && !TT.f) {
346 if (!*ss) error_exit("no REGEX");
347 TT.e = xzalloc(sizeof(struct arg_list));
354 if (!(toys.optflags & FLAG_h) && toys.optc>1) toys.optflags |= FLAG_H;
357 if (toys.optflags & FLAG_s) {
359 xopen("/dev/null", O_RDWR);
362 if (toys.optflags & FLAG_r) {
363 // Iterate through -r arguments. Use "." as default if none provided.
364 for (ss = *ss ? ss : (char *[]){".", 0}; *ss; ss++) {
365 if (!strcmp(*ss, "-")) do_grep(0, *ss);
366 else dirtree_read(*ss, do_grep_r);
368 } else loopfiles_rw(ss, O_RDONLY, 0, 1, do_grep);