aboutsummaryrefslogtreecommitdiff
path: root/toys/posix/grep.c
blob: b92294ed97ef2baea25187c2e7639a4c7be8b59a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
/* grep.c - show lines matching regular expressions
 *
 * Copyright 2013 CE Strake <strake888 at gmail.com>
 *
 * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/grep.html
 *
 * Posix doesn't even specify -r, documenting deviations from it is silly.
* echo hello | grep -w ''
* echo '' | grep -w ''
* echo hello | grep -f </dev/null
*

USE_GREP(NEWTOY(grep, "(line-buffered)(color):;(exclude-dir)*S(exclude)*M(include)*ZzEFHIab(byte-offset)h(no-filename)ino(only-matching)rRsvwcl(files-with-matches)q(quiet)(silent)e*f*C#B#A#m#x[!wx][!EFw]", TOYFLAG_BIN|TOYFLAG_ARGFAIL(2)))
USE_EGREP(OLDTOY(egrep, grep, TOYFLAG_BIN|TOYFLAG_ARGFAIL(2)))
USE_FGREP(OLDTOY(fgrep, grep, TOYFLAG_BIN|TOYFLAG_ARGFAIL(2)))

config GREP
  bool "grep"
  default y
  help
    usage: grep [-EFrivwcloqsHbhn] [-ABC NUM] [-m MAX] [-e REGEX]... [-MS PATTERN]... [-f REGFILE] [FILE]...

    Show lines matching regular expressions. If no -e, first argument is
    regular expression to match. With no files (or "-" filename) read stdin.
    Returns 0 if matched, 1 if no match found, 2 for command errors.

    -e  Regex to match. (May be repeated.)
    -f  File listing regular expressions to match.

    file search:
    -r  Recurse into subdirectories (defaults FILE to ".")
    -R  Recurse into subdirectories and symlinks to directories
    -M  Match filename pattern (--include)
    -S  Skip filename pattern (--exclude)
    --exclude-dir=PATTERN  Skip directory pattern
    -I  Ignore binary files

    match type:
    -A  Show NUM lines after     -B  Show NUM lines before match
    -C  NUM lines context (A+B)  -E  extended regex syntax
    -F  fixed (literal match)    -a  always text (not binary)
    -i  case insensitive         -m  match MAX many lines
    -v  invert match             -w  whole word (implies -E)
    -x  whole line               -z  input NUL terminated

    display modes: (default: matched line)
    -c  count of matching lines  -l  show only matching filenames
    -o  only matching part       -q  quiet (errors only)
    -s  silent (no error msg)    -Z  output NUL terminated

    output prefix (default: filename if checking more than 1 file)
    -H  force filename           -b  byte offset of match
    -h  hide filename            -n  line number of match

config EGREP
  bool
  default y
  depends on GREP

config FGREP
  bool
  default y
  depends on GREP
*/

#define FOR_grep
#include "toys.h"
#include <regex.h>

GLOBALS(
  long m, A, B, C;
  struct arg_list *f, *e, *M, *S, *exclude_dir;
  char *color;

  char *purple, *cyan, *red, *green, *grey;
  struct double_list *reg;
  char indelim, outdelim;
  int found, tried;
)

struct reg {
  struct reg *next, *prev;
  int rc;
  regex_t r;
  regmatch_t m;
};

static void numdash(long num, char dash)
{
  printf("%s%ld%s%c", TT.green, num, TT.cyan, dash);
}

// Emit line with various potential prefixes and delimiter
static void outline(char *line, char dash, char *name, long lcount, long bcount,
  unsigned trim)
{
  if (!trim && FLAG(o)) return;
  if (name && FLAG(H)) printf("%s%s%s%c", TT.purple, name, TT.cyan, dash);
  if (FLAG(c)) {
    printf("%s%ld", TT.grey, lcount);
    xputc(TT.outdelim);
  } else if (lcount && FLAG(n)) numdash(lcount, dash);
  if (bcount && FLAG(b)) numdash(bcount-1, dash);
  if (line) {
    if (FLAG(color)) xputsn(FLAG(o) ? TT.red : TT.grey);
    // support embedded NUL bytes in output
    xputsl(line, trim);
    xputc(TT.outdelim);
  }
}

// Show matches in one file
static void do_grep(int fd, char *name)
{
  long lcount = 0, mcount = 0, offset = 0, after = 0, before = 0;
  struct double_list *dlb = 0;
  char *bars = 0;
  FILE *file;
  int bin = 0;

  if (!FLAG(r)) TT.tried++;
  if (!fd) name = "(standard input)";

  // Only run binary file check on lseekable files.
  if (!FLAG(a) && !lseek(fd, 0, SEEK_CUR)) {
    char buf[256];
    int len, i = 0;
    wchar_t wc;

    // If the first 256 bytes don't parse as utf8, call it binary.
    if (0<(len = read(fd, buf, 256))) {
      lseek(fd, -len, SEEK_CUR);
      while (i<len) {
        bin = utf8towc(&wc, buf+i, len-i);
        if (bin == -2) i = len;
        if (bin<1) break;
        i += bin;
      }
      bin = i!=len;
    }
    if (bin && FLAG(I)) return;
  }

  if (!(file = fdopen(fd, "r"))) return perror_msg("%s", name);

  // Loop through lines of input
  for (;;) {
    char *line = 0, *start;
    struct reg *shoe;
    size_t ulen;
    long len;
    int matched = 0, rc = 1;

    // get next line, check and trim delimiter
    lcount++;
    errno = 0;
    ulen = len = getdelim(&line, &ulen, TT.indelim, file);
    if (errno) perror_msg("%s", name);
    if (len<1) break;
    if (line[ulen-1] == TT.indelim) line[--ulen] = 0;

    // Prepare for next line
    start = line;
    if (TT.reg) for (shoe = (void *)TT.reg; shoe; shoe = shoe->next)
      shoe->rc = 0;

    // Loop to handle multiple matches in same line
    do {
      regmatch_t *mm = (void *)toybuf;

      // Handle "fixed" (literal) matches
      if (FLAG(F)) {
        struct arg_list *seek, fseek;
        char *s = 0;

        for (seek = TT.e; seek; seek = seek->next) {
          if (FLAG(x)) {
            if (!(FLAG(i) ? strcasecmp : strcmp)(seek->arg, line)) s = line;
          } else if (!*seek->arg) {
            seek = &fseek;
            fseek.arg = s = line;
          } else if (FLAG(i)) s = strcasestr(line, seek->arg);
          else s = strstr(line, seek->arg);

          if (s) break;
        }

        if (s) {
          rc = 0;
          mm->rm_so = (s-line);
          mm->rm_eo = (s-line)+strlen(seek->arg);
        } else rc = 1;

      // Handle regex matches
      } else {
        int baseline = mm->rm_eo;

        mm->rm_so = mm->rm_eo = INT_MAX;
        rc = 1;
        for (shoe = (void *)TT.reg; shoe; shoe = shoe->next) {

          // Do we need to re-check this regex?
          if (!shoe->rc) {
            shoe->m.rm_so -= baseline;
            shoe->m.rm_eo -= baseline;
            if (!matched || shoe->m.rm_so<0)
              shoe->rc = regexec0(&shoe->r, start, ulen-(start-line), 1,
                                  &shoe->m, start==line ? 0 : REG_NOTBOL);
          }

          // If we got a match, is it a _better_ match?
          if (!shoe->rc && (shoe->m.rm_so < mm->rm_so ||
              (shoe->m.rm_so == mm->rm_so && shoe->m.rm_eo >= mm->rm_eo)))
          {
            mm = &shoe->m;
            rc = 0;
          }
        }
      }

      if (!rc && FLAG(x))
        if (mm->rm_so || line[mm->rm_eo]) rc = 1;

      if (!rc && FLAG(w)) {
        char c = 0;

        if ((start+mm->rm_so)!=line) {
          c = start[mm->rm_so-1];
          if (!isalnum(c) && c != '_') c = 0;
        }
        if (!c) {
          c = start[mm->rm_eo];
          if (!isalnum(c) && c != '_') c = 0;
        }
        if (c) {
          start += mm->rm_so+1;
          continue;
        }
      }

      if (FLAG(v)) {
        if (FLAG(o)) {
          if (rc) {
            mm->rm_so = 0;
            mm->rm_eo = ulen-(start-line);
          } else if (!mm->rm_so) {
            start += mm->rm_eo;
            continue;
          } else mm->rm_eo = mm->rm_so;
        } else {
          if (!rc) break;
          mm->rm_eo = ulen-(start-line);
        }
        mm->rm_so = 0;
      } else if (rc) break;

      // At least one line we didn't print since match while -ABC active
      if (bars) {
        xputs(bars);
        bars = 0;
      }
      matched++;
      TT.found = 1;
      if (FLAG(q)) {
        toys.exitval = 0;
        xexit();
      }
      if (FLAG(l)) {
        xprintf("%s%c", name, TT.outdelim);
        free(line);
        fclose(file);
        return;
      }

      if (!FLAG(c)) {
        long bcount = 1 + offset + (start-line) + (FLAG(o) ? mm->rm_so : 0);
 
        if (bin) printf("Binary file %s matches\n", name);
        else if (FLAG(o))
          outline(start+mm->rm_so, ':', name, lcount, bcount,
                  mm->rm_eo-mm->rm_so);
        else {
          while (dlb) {
            struct double_list *dl = dlist_pop(&dlb);
            unsigned *uu = (void *)(dl->data+((strlen(dl->data)+1)|3)+1);

            outline(dl->data, '-', name, lcount-before, uu[0]+1, uu[1]);
            free(dl->data);
            free(dl);
            before--;
          }

          if (matched==1)
            outline(FLAG(color) ? 0 : line, ':', name, lcount, bcount, ulen);
          if (FLAG(color)) {
            xputsn(TT.grey);
            if (mm->rm_so) xputsl(line, mm->rm_so);
            xputsn(TT.red);
            xputsl(line+mm->rm_so, mm->rm_eo-mm->rm_so);
          }

          if (TT.A) after = TT.A+1;
        }
      }

      start += mm->rm_eo;
      if (mm->rm_so == mm->rm_eo) break;
      if (!FLAG(o) && FLAG(color)) break;
    } while (*start);
    offset += len;

    if (matched) {
      // Finish off pending line color fragment.
      if (FLAG(color) && !FLAG(o)) {
        xputsn(TT.grey);
        if (ulen > start-line) xputsl(start, ulen-(start-line));
        xputc(TT.outdelim);
      }
      mcount++;
    } else {
      int discard = (after || TT.B);

      if (after && --after) {
        outline(line, '-', name, lcount, 0, ulen);
        discard = 0;
      }
      if (discard && TT.B) {
        unsigned *uu, ul = (ulen+1)|3;

        line = xrealloc(line, ul+8);
        uu = (void *)(line+ul+1);
        uu[0] = offset-len;
        uu[1] = ulen;
        dlist_add(&dlb, line);
        line = 0;
        if (++before>TT.B) {
          struct double_list *dl;

          dl = dlist_pop(&dlb);
          free(dl->data);
          free(dl);
          before--;
        } else discard = 0;
      }
      // If we discarded a line while displaying context, show bars before next
      // line (but don't show them now in case that was last match in file)
      if (discard && mcount) bars = "--";
    }
    free(line);

    if (FLAG(m) && mcount >= TT.m) break;
  }

  if (FLAG(c)) outline(0, ':', name, mcount, 0, 1);

  // loopfiles will also close the fd, but this frees an (opaque) struct.
  fclose(file);
  while (dlb) {
    struct double_list *dl = dlist_pop(&dlb);

    free(dl->data);
    free(dl);
  }
}

static void parse_regex(void)
{
  struct arg_list *al, *new, *list = NULL;
  char *s, *ss;

  // Add all -f lines to -e list. (Yes, this is leaking allocation context for
  // exit to free. Not supporting nofork for this command any time soon.)
  al = TT.f ? TT.f : TT.e;
  while (al) {
    if (TT.f) s = ss = xreadfile(al->arg, 0, 0);
    else s = ss = al->arg;

    // Split lines at \n, add individual lines to new list.
    do {
// TODO: NUL terminated input shouldn't split -e at \n
      ss = strchr(s, '\n');
      if (ss) *(ss++) = 0;
      new = xmalloc(sizeof(struct arg_list));
      new->next = list;
      new->arg = s;
      list = new;
      s = ss;
    } while (ss && *s);

    // Advance, when we run out of -f switch to -e.
    al = al->next;
    if (!al && TT.f) {
      TT.f = 0;
      al = TT.e;
    }
  }
  TT.e = list;

  if (!FLAG(F)) {
    int i;

    // Convert regex list
    for (al = TT.e; al; al = al->next) {
      struct reg *shoe;

      if (FLAG(o) && !*al->arg) continue;
      dlist_add_nomalloc(&TT.reg, (void *)(shoe = xmalloc(sizeof(struct reg))));
      i = regcomp(&shoe->r, al->arg,
                  (REG_EXTENDED*!!FLAG(E)) | (REG_ICASE*!!FLAG(i)));
      if (i) {
        regerror(i, &shoe->r, toybuf, sizeof(toybuf));
        error_exit("bad REGEX '%s': %s", al->arg, toybuf);
      }
    }
    dlist_terminate(TT.reg);
  }
}

static int do_grep_r(struct dirtree *new)
{
  struct arg_list *al;
  char *name;

  if (!new->parent) TT.tried++;
  if (!dirtree_notdotdot(new)) return 0;
  if (S_ISDIR(new->st.st_mode)) {
    for (al = TT.exclude_dir; al; al = al->next)
      if (!fnmatch(al->arg, new->name, 0)) return 0;
    return DIRTREE_RECURSE|(FLAG(R)?DIRTREE_SYMFOLLOW:0);
  }
  if (TT.S || TT.M) {
    for (al = TT.S; al; al = al->next)
      if (!fnmatch(al->arg, new->name, 0)) return 0;

    if (TT.M) {
      for (al = TT.M; al; al = al->next)
        if (!fnmatch(al->arg, new->name, 0)) break;

      if (!al) return 0;
    }
  }

  // "grep -r onefile" doesn't show filenames, but "grep -r onedir" should.
  if (new->parent && !FLAG(h)) toys.optflags |= FLAG_H;

  name = dirtree_path(new, 0);
  do_grep(openat(dirtree_parentfd(new), new->name, 0), name);
  free(name);

  return 0;
}

void grep_main(void)
{
  char **ss = toys.optargs;

  if (FLAG(color) && (!TT.color || !strcmp(TT.color, "auto")) && !isatty(1))
    toys.optflags &= ~FLAG_color;

  if (FLAG(color)) {
    TT.purple = "\033[35m";
    TT.cyan = "\033[36m";
    TT.red = "\033[1;31m";
    TT.green = "\033[32m";
    TT.grey = "\033[0m";
  } else TT.purple = TT.cyan = TT.red = TT.green = TT.grey = "";

  if (FLAG(R)) toys.optflags |= FLAG_r;

  // Grep exits with 2 for errors
  toys.exitval = 2;

  if (!TT.A) TT.A = TT.C;
  if (!TT.B) TT.B = TT.C;

  TT.indelim = '\n' * !FLAG(z);
  TT.outdelim = '\n' * !FLAG(Z);

  // Handle egrep and fgrep
  if (*toys.which->name == 'e') toys.optflags |= FLAG_E;
  if (*toys.which->name == 'f') toys.optflags |= FLAG_F;

  if (!TT.e && !TT.f) {
    if (!*ss) error_exit("no REGEX");
    TT.e = xzalloc(sizeof(struct arg_list));
    TT.e->arg = *(ss++);
    toys.optc--;
  }

  parse_regex();

  if (!FLAG(h) && toys.optc>1) toys.optflags |= FLAG_H;

  if (FLAG(s)) {
    close(2);
    xopen_stdio("/dev/null", O_RDWR);
  }

  if (FLAG(r)) {
    // Iterate through -r arguments. Use "." as default if none provided.
    for (ss = *ss ? ss : (char *[]){".", 0}; *ss; ss++) {
      if (!strcmp(*ss, "-")) do_grep(0, *ss);
      else dirtree_read(*ss, do_grep_r);
    }
  } else loopfiles_rw(ss, O_RDONLY|WARN_ONLY, 0, do_grep);
  if (TT.tried >= toys.optc || (FLAG(q)&&TT.found)) toys.exitval = !TT.found;
}