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: -ABC 8 9USE_GREP(NEWTOY(grep, "C#B#A#ZzEFHabhinorsvwclqe*f*m#x[!wx][!EFw]", TOYFLAG_BIN)) 10USE_EGREP(OLDTOY(egrep, grep, TOYFLAG_BIN)) 11USE_FGREP(OLDTOY(fgrep, grep, TOYFLAG_BIN)) 12 13config GREP 14 bool "grep" 15 default y 16 help 17 usage: grep [-EFivwcloqsHbhn] [-A NUM] [-m MAX] [-e REGEX]... [-f REGFILE] [FILE]... 18 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. 22 23 -e Regex to match. (May be repeated.) 24 -f File containing regular expressions to match. 25 26 match type: 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 33 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 38 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 42 43config EGREP 44 bool 45 default y 46 depends on GREP 47 48config FGREP 49 bool 50 default y 51 depends on GREP 52*/ 53 54#define FOR_grep 55#include "toys.h" 56#include <regex.h> 57 58GLOBALS( 59 long m; 60 struct arg_list *f; 61 struct arg_list *e; 62 long a; 63 long b; 64 long c; 65 66 char indelim, outdelim; 67) 68 69// Emit line with various potential prefixes and delimiter 70static void outline(char *line, char dash, char *name, long lcount, long bcount, 71 int trim) 72{ 73 if (name && (toys.optflags&FLAG_H)) printf("%s%c", name, dash); 74 if (!line || (lcount && (toys.optflags&FLAG_n))) 75 printf("%ld%c", lcount, line ? dash : TT.outdelim); 76 if (bcount && (toys.optflags&FLAG_b)) printf("%ld%c", bcount-1, dash); 77 if (line) xprintf("%.*s%c", trim, line, TT.outdelim); 78} 79 80// Show matches in one file 81static void do_grep(int fd, char *name) 82{ 83 struct double_list *dlb = 0; 84 FILE *file = xfdopen(fd, "r"); 85 long lcount = 0, mcount = 0, offset = 0, after = 0, before = 0; 86 char *bars = 0; 87 88 if (!fd) name = "(standard input)"; 89 90 // Loop through lines of input 91 for (;;) { 92 char *line = 0, *start; 93 regmatch_t matches; 94 size_t unused; 95 long len; 96 int mmatch = 0; 97 98 lcount++; 99 if (0 > (len = getdelim(&line, &unused, TT.indelim, file))) break; 100 if (line[len-1] == TT.indelim) line[len-1] = 0; 101 102 start = line; 103 104 // Loop through matches in this line 105 do { 106 int rc = 0, skip = 0; 107 108 // Handle non-regex matches 109 if (toys.optflags & FLAG_F) { 110 struct arg_list *seek, fseek; 111 char *s = 0; 112 113 for (seek = TT.e; seek; seek = seek->next) { 114 if (toys.optflags & FLAG_x) { 115 int i = (toys.optflags & FLAG_i); 116 117 if ((i ? strcasecmp : strcmp)(seek->arg, line)) s = line; 118 } else if (!*seek->arg) { 119 seek = &fseek; 120 fseek.arg = s = line; 121 break; 122 } 123 if (toys.optflags & FLAG_i) s = strnstr(line, seek->arg); 124 else s = strstr(line, seek->arg); 125 if (s) break; 126 } 127 128 if (s) { 129 matches.rm_so = (s-line); 130 skip = matches.rm_eo = (s-line)+strlen(seek->arg); 131 } else rc = 1; 132 } else { 133 rc = regexec((regex_t *)toybuf, start, 1, &matches, 134 start==line ? 0 : REG_NOTBOL); 135 skip = matches.rm_eo; 136 } 137 138 if (toys.optflags & FLAG_x) 139 if (matches.rm_so || line[matches.rm_eo]) rc = 1; 140 141 if (!rc && (toys.optflags & FLAG_w)) { 142 char c = 0; 143 144 if ((start+matches.rm_so)!=line) { 145 c = start[matches.rm_so-1]; 146 if (!isalnum(c) && c != '_') c = 0; 147 } 148 if (!c) { 149 c = start[matches.rm_eo]; 150 if (!isalnum(c) && c != '_') c = 0; 151 } 152 if (c) { 153 start += matches.rm_so+1; 154 155 continue; 156 } 157 } 158 159 if (toys.optflags & FLAG_v) { 160 if (toys.optflags & FLAG_o) { 161 if (rc) skip = matches.rm_eo = strlen(start); 162 else if (!matches.rm_so) { 163 start += skip; 164 continue; 165 } else matches.rm_eo = matches.rm_so; 166 } else { 167 if (!rc) break; 168 matches.rm_eo = strlen(start); 169 } 170 matches.rm_so = 0; 171 } else if (rc) break; 172 173 // At least one line we didn't print since match while -ABC active 174 if (bars) { 175 xputs(bars); 176 bars = 0; 177 } 178 mmatch++; 179 toys.exitval = 0; 180 if (toys.optflags & FLAG_q) xexit(); 181 if (toys.optflags & FLAG_l) { 182 xprintf("%s%c", name, TT.outdelim); 183 free(line); 184 fclose(file); 185 return; 186 } 187 if (toys.optflags & FLAG_o) 188 if (matches.rm_eo == matches.rm_so) 189 break; 190 191 if (!(toys.optflags & FLAG_c)) { 192 long bcount = 1 + offset + (start-line) + 193 ((toys.optflags & FLAG_o) ? matches.rm_so : 0); 194 195 if (!(toys.optflags & FLAG_o)) { 196 while (dlb) { 197 struct double_list *dl = dlist_pop(&dlb); 198 199 outline(dl->data, '-', name, lcount-before, 0, -1); 200 free(dl->data); 201 free(dl); 202 before--; 203 } 204 205 outline(line, ':', name, lcount, bcount, -1); 206 if (TT.a) after = TT.a+1; 207 } else outline(start+matches.rm_so, ':', name, lcount, bcount, 208 matches.rm_eo-matches.rm_so); 209 } 210 211 start += skip; 212 if (!(toys.optflags & FLAG_o)) break; 213 } while (*start); 214 offset += len; 215 216 if (mmatch) mcount++; 217 else { 218 int discard = (after || TT.b); 219 220 if (after && --after) { 221 outline(line, '-', name, lcount, 0, -1); 222 discard = 0; 223 } 224 if (discard && TT.b) { 225 dlist_add(&dlb, line); 226 line = 0; 227 if (++before>TT.b) { 228 struct double_list *dl; 229 230 dl = dlist_pop(&dlb); 231 free(dl->data); 232 free(dl); 233 before--; 234 } else discard = 0; 235 } 236 // If we discarded a line while displaying context, show bars before next 237 // line (but don't show them now in case that was last match in file) 238 if (discard && mcount) bars = "--"; 239 } 240 free(line); 241 242 if ((toys.optflags & FLAG_m) && mcount >= TT.m) break; 243 } 244 245 if (toys.optflags & FLAG_c) outline(0, ':', name, mcount, 0, -1); 246 247 // loopfiles will also close the fd, but this frees an (opaque) struct. 248 fclose(file); 249} 250 251static void parse_regex(void) 252{ 253 struct arg_list *al, *new, *list = NULL; 254 long len = 0; 255 char *s, *ss; 256 257 // Add all -f lines to -e list. (Yes, this is leaking allocation context for 258 // exit to free. Not supporting nofork for this command any time soon.) 259 al = TT.f ? TT.f : TT.e; 260 while (al) { 261 if (TT.f) s = ss = xreadfile(al->arg, 0, 0); 262 else s = ss = al->arg; 263 264 // Split lines at \n, add individual lines to new list. 265 do { 266 ss = strchr(s, '\n'); 267 if (ss) *(ss++) = 0; 268 new = xmalloc(sizeof(struct arg_list)); 269 new->next = list; 270 new->arg = s; 271 list = new; 272 s = ss; 273 } while (ss && *s); 274 275 // Advance, when we run out of -f switch to -e. 276 al = al->next; 277 if (!al && TT.f) { 278 TT.f = 0; 279 al = TT.e; 280 } 281 } 282 TT.e = list; 283 284 if (!(toys.optflags & FLAG_F)) { 285 char *regstr; 286 int i; 287 288 // Convert strings to one big regex 289 for (al = TT.e; al; al = al->next) 290 len += strlen(al->arg)+1+!(toys.optflags & FLAG_E); 291 292 regstr = s = xmalloc(len); 293 for (al = TT.e; al; al = al->next) { 294 s = stpcpy(s, al->arg); 295 if (!(toys.optflags & FLAG_E)) *(s++) = '\\'; 296 *(s++) = '|'; 297 } 298 *(s-=(1+!(toys.optflags & FLAG_E))) = 0; 299 300 i = regcomp((regex_t *)toybuf, regstr, 301 ((toys.optflags & FLAG_E) ? REG_EXTENDED : 0) | 302 ((toys.optflags & FLAG_i) ? REG_ICASE : 0)); 303 304 if (i) { 305 regerror(i, (regex_t *)toybuf, toybuf+sizeof(regex_t), 306 sizeof(toybuf)-sizeof(regex_t)); 307 error_exit("bad REGEX: %s", toybuf); 308 } 309 } 310} 311 312static int do_grep_r(struct dirtree *new) 313{ 314 char *name; 315 316 if (!dirtree_notdotdot(new)) return 0; 317 if (S_ISDIR(new->st.st_mode)) return DIRTREE_RECURSE; 318 319 // "grep -r onefile" doesn't show filenames, but "grep -r onedir" should. 320 if (new->parent && !(toys.optflags & FLAG_h)) toys.optflags |= FLAG_H; 321 322 name = dirtree_path(new, 0); 323 do_grep(openat(dirtree_parentfd(new), new->name, 0), name); 324 free(name); 325 326 return 0; 327} 328 329void grep_main(void) 330{ 331 char **ss = toys.optargs; 332 333 if (!TT.a) TT.a = TT.c; 334 if (!TT.b) TT.b = TT.c; 335 336 TT.indelim = '\n' * !(toys.optflags&FLAG_z); 337 TT.outdelim = '\n' * !(toys.optflags&FLAG_Z); 338 339 // Handle egrep and fgrep 340 if (*toys.which->name == 'e') toys.optflags |= FLAG_E; 341 if (*toys.which->name == 'f') toys.optflags |= FLAG_F; 342 343 if (!TT.e && !TT.f) { 344 if (!*ss) error_exit("no REGEX"); 345 TT.e = xzalloc(sizeof(struct arg_list)); 346 TT.e->arg = *(ss++); 347 toys.optc--; 348 } 349 350 parse_regex(); 351 352 if (!(toys.optflags & FLAG_h) && toys.optc>1) toys.optflags |= FLAG_H; 353 354 toys.exitval = 1; 355 if (toys.optflags & FLAG_s) { 356 close(2); 357 xopen_stdio("/dev/null", O_RDWR); 358 } 359 360 if (toys.optflags & FLAG_r) { 361 // Iterate through -r arguments. Use "." as default if none provided. 362 for (ss = *ss ? ss : (char *[]){".", 0}; *ss; ss++) { 363 if (!strcmp(*ss, "-")) do_grep(0, *ss); 364 else dirtree_read(*ss, do_grep_r); 365 } 366 } else loopfiles_rw(ss, O_RDONLY|WARN_ONLY, 0, do_grep); 367} 368