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[PATCH v2 28/29] grep: given --threads with NO_PTHREADS=YesPlease, warn

From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date
May 13, 2017, 23:15 UTC
Message-ID
<20170513231509.7834-29-avarab@gmail.com>
In-Reply-To
<20170513231509.7834-1-avarab@gmail.com>

Add a warning about missing thread support when grep.threads or --threads is set to a non 0 (default) or 1 (no parallelism) value under NO_PTHREADS=YesPlease.

This is for consistency with the index-pack & pack-objects commands, which also take a --threads option & are configurable via pack.threads, and have long warned about the same under NO_PTHREADS=YesPlease.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 builtin/grep.c  | 13 +++++++++++++
 t/t7810-grep.sh | 18 ++++++++++++++++++
 2 files changed, 31 insertions(+)
diff --git a/builtin/grep.c b/builtin/grep.c
index a191e2976b..3c721b75a5 100644
--- a/builtin/grep.c
+++ b/builtin/grep.c
@@ -289,6 +289,17 @@ static int grep_cmd_config(const char *var, const char *value, void *cb)
 		if (num_threads < 0)
 			die(_("invalid number of threads specified (%d) for %s"),
 			    num_threads, var);
+#ifdef NO_PTHREADS
+		else if (num_threads && num_threads != 1) {
+			/*
+			 * TRANSLATORS: %s is the configuration
+			 * variable for tweaking threads, currently
+			 * grep.threads
+			 */
+			warning(_("no threads support, ignoring %s"), var);
+			num_threads = 0;
+		}
+#endif
 	}
 
 	return st;
@@ -1229,6 +1240,8 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
 	else if (num_threads < 0)
 		die(_("invalid number of threads specified (%d)"), num_threads);
 #else
+	if (num_threads)
+		warning(_("no threads support, ignoring --threads"));
 	num_threads = 0;
 #endif
 
diff --git a/t/t7810-grep.sh b/t/t7810-grep.sh
index 561709ef6a..f106387820 100755
--- a/t/t7810-grep.sh
+++ b/t/t7810-grep.sh
@@ -791,6 +791,24 @@ do
 	"
 done
 
+test_expect_success !PTHREADS,C_LOCALE_OUTPUT 'grep --threads=N or pack.threads=N warns when no pthreads' '
+	git grep --threads=2 Hello hello_world 2>err &&
+	grep ^warning: err >warnings &&
+	test_line_count = 1 warnings &&
+	grep -F "no threads support, ignoring --threads" err &&
+	git -c grep.threads=2 grep Hello hello_world 2>err &&
+	grep ^warning: err >warnings &&
+	test_line_count = 1 warnings &&
+	grep -F "no threads support, ignoring grep.threads" err &&
+	git -c grep.threads=2 grep --threads=4 Hello hello_world 2>err &&
+	grep ^warning: err >warnings &&
+	test_line_count = 2 warnings &&
+	grep -F "no threads support, ignoring --threads" err &&
+	grep -F "no threads support, ignoring grep.threads" err &&
+	git -c grep.threads=0 grep --threads=0 Hello hello_world 2>err &&
+	test_line_count = 0 err
+'
+
 test_expect_success 'grep from a subdirectory to search wider area (1)' '
 	mkdir -p s &&
 	(
-- 
2.11.0
Previous: Ævar Arnfjörð BjarmasonNext: Ævar Arnfjörð Bjarmason
Message 40 of 42 in “Easy to review grep & pre-PCRE changes”
  1. 00/29 Easy to review grep & pre-PCRE changesÆvar Arnfjörð Bjarmason, May 13, 2017
  2. 01/29 Makefile & configure: reword inaccurate comment about PCREÆvar Arnfjörð Bjarmason, May 13, 2017
  3. 02/29 grep & rev-list doc: stop promising libpcre for --perl-regexpÆvar Arnfjörð Bjarmason, May 13, 2017
  4. 04/29 log: add exhaustive tests for pattern style options & configÆvar Arnfjörð Bjarmason, May 13, 2017
  5. Junio C HamanoMay 15, 2017
  6. Ævar Arnfjörð BjarmasonMay 15, 2017
  7. Junio C HamanoMay 16, 2017
  8. 05/29 grep: add a test asserting that --perl-regexp dies when !PCREÆvar Arnfjörð Bjarmason, May 13, 2017
  9. 03/29 test-lib: rename the LIBPCRE prerequisite to PCREÆvar Arnfjörð Bjarmason, May 13, 2017
  10. 06/29 grep: add a test for backreferences in PCRE patternsÆvar Arnfjörð Bjarmason, May 13, 2017
  11. 07/29 grep: change non-ASCII -i test to stop using --debugÆvar Arnfjörð Bjarmason, May 13, 2017
  12. 08/29 grep: add tests for --threads=N and grep.threadsÆvar Arnfjörð Bjarmason, May 13, 2017
  13. 09/29 grep: amend submodule recursion test for regex engine testingÆvar Arnfjörð Bjarmason, May 13, 2017
  14. 10/29 grep: add tests for grep pattern types being passed to submodulesÆvar Arnfjörð Bjarmason, May 13, 2017
  15. 11/29 grep: add a test helper function for less verbose -f \0 testsÆvar Arnfjörð Bjarmason, May 13, 2017
  16. 12/29 grep: prepare for testing binary regexes containing rx metacharactersÆvar Arnfjörð Bjarmason, May 13, 2017
  17. 13/29 grep: add tests to fix blind spots with \0 patternsÆvar Arnfjörð Bjarmason, May 13, 2017
  18. 14/29 perf: add a GIT_PERF_MAKE_COMMAND for when *_MAKE_OPTS won't doÆvar Arnfjörð Bjarmason, May 13, 2017
  19. 15/29 perf: emit progress output when unpacking & buildingÆvar Arnfjörð Bjarmason, May 13, 2017
  20. 16/29 perf: add a performance comparison test of grep -G, -E and -PÆvar Arnfjörð Bjarmason, May 13, 2017
  21. 18/29 grep: catch a missing enum in switch statementÆvar Arnfjörð Bjarmason, May 13, 2017
  22. Junio C HamanoMay 15, 2017
  23. Ævar Arnfjörð BjarmasonMay 15, 2017
  24. 17/29 perf: add a performance comparison of fixed-string grepÆvar Arnfjörð Bjarmason, May 13, 2017
  25. 20/29 grep: remove redundant `regflags &= ~REG_EXTENDED` assignmentsÆvar Arnfjörð Bjarmason, May 13, 2017
  26. Junio C HamanoMay 15, 2017
  27. Ævar Arnfjörð BjarmasonMay 15, 2017
  28. 19/29 grep: remove redundant regflags assignment under PCREÆvar Arnfjörð Bjarmason, May 13, 2017
  29. 21/29 grep: factor test for \0 in grep patterns into a functionÆvar Arnfjörð Bjarmason, May 13, 2017
  30. Junio C HamanoMay 15, 2017
  31. Ævar Arnfjörð BjarmasonMay 15, 2017
  32. 22/29 grep: change the internal PCRE macro names to be PCRE1Ævar Arnfjörð Bjarmason, May 13, 2017
  33. 23/29 grep: change internal *pcre* variable & function names to be *pcre1*Ævar Arnfjörð Bjarmason, May 13, 2017
  34. 25/29 test-lib: add a PTHREADS prerequisiteÆvar Arnfjörð Bjarmason, May 13, 2017
  35. 26/29 pack-objects & index-pack: add test for --threads warningÆvar Arnfjörð Bjarmason, May 13, 2017
  36. 24/29 grep: move is_fixed() earlier to avoid forward declarationÆvar Arnfjörð Bjarmason, May 13, 2017
  37. 27/29 pack-objects: fix buggy warning about threadsÆvar Arnfjörð Bjarmason, May 13, 2017
  38. Junio C HamanoMay 15, 2017
  39. Ævar Arnfjörð BjarmasonMay 15, 2017
  40. 28/29 grep: given --threads with NO_PTHREADS=YesPlease, warnÆvar Arnfjörð Bjarmason, May 13, 2017
  41. 29/29 grep: assert that threading is enabled when calling grep_{lock,unlock}Ævar Arnfjörð Bjarmason, May 13, 2017
  42. Junio C HamanoMay 15, 2017

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