1 /* grep.c - print lines what match given regular expression
2 *
3 * Copyright 2013 CE Strake <strake888 at gmail.com>
4 *
5 * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/grep.html
6 *
7 * TODO: --color, "Binary file %s matches"
8 *
9 * Posix doesn't even specify -r, documenting deviations from it is silly.
10
11 USE_GREP(NEWTOY(grep, "S(exclude)*M(include)*C#B#A#ZzEFHabhinorsvwclqe*f*m#x[!wx][!EFw]", TOYFLAG_BIN))
12 USE_EGREP(OLDTOY(egrep, grep, TOYFLAG_BIN))
13 USE_FGREP(OLDTOY(fgrep, grep, TOYFLAG_BIN))
14
15 config GREP
16 bool "grep"
17 default y
18 help
19 usage: grep [-EFrivwcloqsHbhn] [-ABC NUM] [-m MAX] [-e REGEX]... [-MS PATTERN]... [-f REGFILE] [FILE]...
20
21 Show lines matching regular expressions. If no -e, first argument is
22 regular expression to match. With no files (or "-" filename) read stdin.
23 Returns 0 if matched, 1 if no match found.
24
25 -e Regex to match. (May be repeated.)
26 -f File listing regular expressions to match.
27
28 file search:
29 -r Recurse into subdirectories (defaults FILE to ".")
30 -M Match filename pattern (--include)
31 -S Skip filename pattern (--exclude)
32
33 match type:
34 -A Show NUM lines after -B Show NUM lines before match
35 -C NUM lines context (A+B) -E extended regex syntax
36 -F fixed (literal match) -i case insensitive
37 -m match MAX many lines -v invert match
38 -w whole word (implies -E) -x whole line
39 -z input NUL terminated
40
41 display modes: (default: matched line)
42 -c count of matching lines -l show matching filenames
43 -o only matching part -q quiet (errors only)
44 -s silent (no error msg) -Z output NUL terminated
45
46 output prefix (default: filename if checking more than 1 file)
47 -H force filename -b byte offset of match
48 -h hide filename -n line number of match
49
50 config EGREP
51 bool
52 default y
53 depends on GREP
54
55 config FGREP
56 bool
57 default y
58 depends on GREP
59 */
60
61 #define FOR_grep
62 #include "toys.h"
63 #include <regex.h>
64
GLOBALS(long m;struct arg_list * f;struct arg_list * e;long a;long b;long c;struct arg_list * M;struct arg_list * S;char indelim,outdelim;int found;)65 GLOBALS(
66 long m;
67 struct arg_list *f;
68 struct arg_list *e;
69 long a;
70 long b;
71 long c;
72 struct arg_list *M;
73 struct arg_list *S;
74
75 char indelim, outdelim;
76 int found;
77 )
78
79 // Emit line with various potential prefixes and delimiter
80 static void outline(char *line, char dash, char *name, long lcount, long bcount,
81 int trim)
82 {
83 if (name && (toys.optflags&FLAG_H)) printf("%s%c", name, dash);
84 if (!line || (lcount && (toys.optflags&FLAG_n)))
85 printf("%ld%c", lcount, line ? dash : TT.outdelim);
86 if (bcount && (toys.optflags&FLAG_b)) printf("%ld%c", bcount-1, dash);
87 if (line) xprintf("%.*s%c", trim, line, TT.outdelim);
88 }
89
90 // Show matches in one file
do_grep(int fd,char * name)91 static void do_grep(int fd, char *name)
92 {
93 struct double_list *dlb = 0;
94 FILE *file = fdopen(fd, "r");
95 long lcount = 0, mcount = 0, offset = 0, after = 0, before = 0;
96 char *bars = 0;
97
98 if (!fd) name = "(standard input)";
99
100 if (!file) {
101 perror_msg("%s", name);
102
103 return;
104 }
105
106 // Loop through lines of input
107 for (;;) {
108 char *line = 0, *start;
109 regmatch_t matches;
110 size_t unused;
111 long len;
112 int mmatch = 0;
113
114 lcount++;
115 errno = 0;
116 len = getdelim(&line, &unused, TT.indelim, file);
117 if (errno) perror_msg("%s", name);
118 if (len<1) break;
119 if (line[len-1] == TT.indelim) line[len-1] = 0;
120
121 start = line;
122
123 // Loop through matches in this line
124 do {
125 int rc = 0, skip = 0;
126
127 // Handle non-regex matches
128 if (toys.optflags & FLAG_F) {
129 struct arg_list *seek, fseek;
130 char *s = 0;
131
132 for (seek = TT.e; seek; seek = seek->next) {
133 if (toys.optflags & FLAG_x) {
134 int i = (toys.optflags & FLAG_i);
135
136 if ((i ? strcasecmp : strcmp)(seek->arg, line)) s = line;
137 } else if (!*seek->arg) {
138 seek = &fseek;
139 fseek.arg = s = line;
140 break;
141 }
142 if (toys.optflags & FLAG_i) s = strnstr(line, seek->arg);
143 else s = strstr(line, seek->arg);
144 if (s) break;
145 }
146
147 if (s) {
148 matches.rm_so = (s-line);
149 skip = matches.rm_eo = (s-line)+strlen(seek->arg);
150 } else rc = 1;
151 } else {
152 rc = regexec((regex_t *)toybuf, start, 1, &matches,
153 start==line ? 0 : REG_NOTBOL);
154 skip = matches.rm_eo;
155 }
156
157 if (toys.optflags & FLAG_x)
158 if (matches.rm_so || line[matches.rm_eo]) rc = 1;
159
160 if (!rc && (toys.optflags & FLAG_w)) {
161 char c = 0;
162
163 if ((start+matches.rm_so)!=line) {
164 c = start[matches.rm_so-1];
165 if (!isalnum(c) && c != '_') c = 0;
166 }
167 if (!c) {
168 c = start[matches.rm_eo];
169 if (!isalnum(c) && c != '_') c = 0;
170 }
171 if (c) {
172 start += matches.rm_so+1;
173
174 continue;
175 }
176 }
177
178 if (toys.optflags & FLAG_v) {
179 if (toys.optflags & FLAG_o) {
180 if (rc) skip = matches.rm_eo = strlen(start);
181 else if (!matches.rm_so) {
182 start += skip;
183 continue;
184 } else matches.rm_eo = matches.rm_so;
185 } else {
186 if (!rc) break;
187 matches.rm_eo = strlen(start);
188 }
189 matches.rm_so = 0;
190 } else if (rc) break;
191
192 // At least one line we didn't print since match while -ABC active
193 if (bars) {
194 xputs(bars);
195 bars = 0;
196 }
197 mmatch++;
198 TT.found = 1;
199 if (toys.optflags & FLAG_q) {
200 toys.exitval = 0;
201 xexit();
202 }
203 if (toys.optflags & FLAG_l) {
204 xprintf("%s%c", name, TT.outdelim);
205 free(line);
206 fclose(file);
207 return;
208 }
209 if (toys.optflags & FLAG_o)
210 if (matches.rm_eo == matches.rm_so)
211 break;
212
213 if (!(toys.optflags & FLAG_c)) {
214 long bcount = 1 + offset + (start-line) +
215 ((toys.optflags & FLAG_o) ? matches.rm_so : 0);
216
217 if (!(toys.optflags & FLAG_o)) {
218 while (dlb) {
219 struct double_list *dl = dlist_pop(&dlb);
220
221 outline(dl->data, '-', name, lcount-before, 0, -1);
222 free(dl->data);
223 free(dl);
224 before--;
225 }
226
227 outline(line, ':', name, lcount, bcount, -1);
228 if (TT.a) after = TT.a+1;
229 } else outline(start+matches.rm_so, ':', name, lcount, bcount,
230 matches.rm_eo-matches.rm_so);
231 }
232
233 start += skip;
234 if (!(toys.optflags & FLAG_o)) break;
235 } while (*start);
236 offset += len;
237
238 if (mmatch) mcount++;
239 else {
240 int discard = (after || TT.b);
241
242 if (after && --after) {
243 outline(line, '-', name, lcount, 0, -1);
244 discard = 0;
245 }
246 if (discard && TT.b) {
247 dlist_add(&dlb, line);
248 line = 0;
249 if (++before>TT.b) {
250 struct double_list *dl;
251
252 dl = dlist_pop(&dlb);
253 free(dl->data);
254 free(dl);
255 before--;
256 } else discard = 0;
257 }
258 // If we discarded a line while displaying context, show bars before next
259 // line (but don't show them now in case that was last match in file)
260 if (discard && mcount) bars = "--";
261 }
262 free(line);
263
264 if ((toys.optflags & FLAG_m) && mcount >= TT.m) break;
265 }
266
267 if (toys.optflags & FLAG_c) outline(0, ':', name, mcount, 0, -1);
268
269 // loopfiles will also close the fd, but this frees an (opaque) struct.
270 fclose(file);
271 }
272
parse_regex(void)273 static void parse_regex(void)
274 {
275 struct arg_list *al, *new, *list = NULL;
276 long len = 0;
277 char *s, *ss;
278
279 // Add all -f lines to -e list. (Yes, this is leaking allocation context for
280 // exit to free. Not supporting nofork for this command any time soon.)
281 al = TT.f ? TT.f : TT.e;
282 while (al) {
283 if (TT.f) s = ss = xreadfile(al->arg, 0, 0);
284 else s = ss = al->arg;
285
286 // Split lines at \n, add individual lines to new list.
287 do {
288 ss = strchr(s, '\n');
289 if (ss) *(ss++) = 0;
290 new = xmalloc(sizeof(struct arg_list));
291 new->next = list;
292 new->arg = s;
293 list = new;
294 s = ss;
295 } while (ss && *s);
296
297 // Advance, when we run out of -f switch to -e.
298 al = al->next;
299 if (!al && TT.f) {
300 TT.f = 0;
301 al = TT.e;
302 }
303 }
304 TT.e = list;
305
306 if (!(toys.optflags & FLAG_F)) {
307 char *regstr;
308 int i;
309
310 // Convert strings to one big regex
311 for (al = TT.e; al; al = al->next)
312 len += strlen(al->arg)+1+!(toys.optflags & FLAG_E);
313
314 regstr = s = xmalloc(len);
315 for (al = TT.e; al; al = al->next) {
316 s = stpcpy(s, al->arg);
317 if (!(toys.optflags & FLAG_E)) *(s++) = '\\';
318 *(s++) = '|';
319 }
320 *(s-=(1+!(toys.optflags & FLAG_E))) = 0;
321
322 i = regcomp((regex_t *)toybuf, regstr,
323 ((toys.optflags & FLAG_E) ? REG_EXTENDED : 0) |
324 ((toys.optflags & FLAG_i) ? REG_ICASE : 0));
325
326 if (i) {
327 regerror(i, (regex_t *)toybuf, toybuf+sizeof(regex_t),
328 sizeof(toybuf)-sizeof(regex_t));
329 error_exit("bad REGEX: %s", toybuf);
330 }
331 }
332 }
333
do_grep_r(struct dirtree * new)334 static int do_grep_r(struct dirtree *new)
335 {
336 char *name;
337
338 if (!dirtree_notdotdot(new)) return 0;
339 if (S_ISDIR(new->st.st_mode)) return DIRTREE_RECURSE;
340 if (TT.S || TT.M) {
341 struct arg_list *al;
342
343 for (al = TT.S; al; al = al->next)
344 if (!fnmatch(al->arg, new->name, 0)) return 0;
345
346 if (TT.M) {
347 for (al = TT.M; al; al = al->next)
348 if (!fnmatch(al->arg, new->name, 0)) break;
349
350 if (!al) return 0;
351 }
352 }
353
354 // "grep -r onefile" doesn't show filenames, but "grep -r onedir" should.
355 if (new->parent && !(toys.optflags & FLAG_h)) toys.optflags |= FLAG_H;
356
357 name = dirtree_path(new, 0);
358 do_grep(openat(dirtree_parentfd(new), new->name, 0), name);
359 free(name);
360
361 return 0;
362 }
363
grep_main(void)364 void grep_main(void)
365 {
366 char **ss = toys.optargs;
367
368 // Grep exits with 2 for errors
369 toys.exitval = 2;
370
371 if (!TT.a) TT.a = TT.c;
372 if (!TT.b) TT.b = TT.c;
373
374 TT.indelim = '\n' * !(toys.optflags&FLAG_z);
375 TT.outdelim = '\n' * !(toys.optflags&FLAG_Z);
376
377 // Handle egrep and fgrep
378 if (*toys.which->name == 'e') toys.optflags |= FLAG_E;
379 if (*toys.which->name == 'f') toys.optflags |= FLAG_F;
380
381 if (!TT.e && !TT.f) {
382 if (!*ss) error_exit("no REGEX");
383 TT.e = xzalloc(sizeof(struct arg_list));
384 TT.e->arg = *(ss++);
385 toys.optc--;
386 }
387
388 parse_regex();
389
390 if (!(toys.optflags & FLAG_h) && toys.optc>1) toys.optflags |= FLAG_H;
391
392 if (toys.optflags & FLAG_s) {
393 close(2);
394 xopen_stdio("/dev/null", O_RDWR);
395 }
396
397 if (toys.optflags & FLAG_r) {
398 // Iterate through -r arguments. Use "." as default if none provided.
399 for (ss = *ss ? ss : (char *[]){".", 0}; *ss; ss++) {
400 if (!strcmp(*ss, "-")) do_grep(0, *ss);
401 else dirtree_read(*ss, do_grep_r);
402 }
403 } else loopfiles_rw(ss, O_RDONLY|WARN_ONLY, 0, do_grep);
404 toys.exitval = !TT.found;
405 }
406