grep: read patterns from stdin with -f -

Support the well-know convention of reading standard input instead of a named file if "-" (dash) is specified. GNU grep does the same. Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>

René Scharfe committed Mar 19, 2011 at 19:33 UTC c41dd2fd7d3a16e6f0b1629d688bee3240db496c

2 files changed +9 -2

builtin/grep.c

+4 -2

@@ -659,11 +659,12 @@ static int context_callback(const struct option *opt, const char *arg,

659 static int file_callback(const struct option *opt, const char *arg, int unset)

660 {

661 struct grep_opt *grep_opt = opt->value;

662 + int from_stdin = !strcmp(arg, "-");

663 FILE *patterns;

664 int lno = 0;

665 struct strbuf sb = STRBUF_INIT;

666

666 - patterns = fopen(arg, "r");

667 + patterns = from_stdin ? stdin : fopen(arg, "r");

668 if (!patterns)

669 die_errno("cannot open '%s'", arg);

670 while (strbuf_getline(&sb, patterns, '\n') == 0) {

@@ -677,7 +678,8 @@ static int file_callback(const struct option *opt, const char *arg, int unset)

678 s = strbuf_detach(&sb, &len);

679 append_grep_pat(grep_opt, s, len, arg, ++lno, GREP_PATTERN);

680 }

680 - fclose(patterns);

681 + if (!from_stdin)

682 + fclose(patterns);

683 strbuf_release(&sb);

684 return 0;

685 }

t/t7810-grep.sh

@@ -303,6 +303,11 @@ test_expect_success 'grep -f, ignore empty lines' '

303 test_cmp expected actual

304 '

305

306 +test_expect_success 'grep -f, ignore empty lines, read patterns from stdin' '

307 + git grep -f - <patterns >actual &&

308 + test_cmp expected actual

309 +'

310 +

311 cat >expected <<EOF

312 y:y yy

313 --