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[PATCH 5/7] submodule: use strbuf_read_cmd

From
Jeff King <peff@peff.net>
Date
Mar 22, 2015, 10:08 UTC
Message-ID
<20150322100858.GE11615@peff.net>
In-Reply-To
<20150322095924.GA24651@peff.net>

In is_submodule_commit_present, we call run_command followed by a pipe read, which is prone to deadlock. It is unlikely to happen in this case, as rev-list should never produce more than a single line of output, but it does not hurt to avoid an anti-pattern (and using the helper simplifies the setup and cleanup).

Signed-off-by: Jeff King <peff@peff.net>
---
 submodule.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/submodule.c b/submodule.c
index d37d400..d85f1bb 100644
--- a/submodule.c
+++ b/submodule.c
@@ -576,12 +576,10 @@ static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 		cp.env = local_repo_env;
 		cp.git_cmd = 1;
 		cp.no_stdin = 1;
-		cp.out = -1;
 		cp.dir = path;
-		if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
+		if (!strbuf_read_cmd(&buf, &cp, 1024) && !buf.len)
 			is_present = 1;
 
-		close(cp.out);
 		strbuf_release(&buf);
 	}
 	return is_present;
-- 
2.3.3.618.ga041503
Previous: Jeff KingNext: Jeff King
Message 24 of 26 in “status hangs trying to get submodule summary”
  1. Wincent ColaiutaMar 22, 2015
  2. status: read submodule process output before calling wait()Jeff King, Mar 22, 2015
  3. Jeff KingMar 22, 2015
  4. 0/7 introduce strbuf_read_cmd to avoid deadlocksJeff King, Mar 22, 2015
  5. 1/7 wt-status: don't flush before running "submodule status"Jeff King, Mar 22, 2015
  6. 2/7 wt_status: fix signedness mismatch in strbuf_read callJeff King, Mar 22, 2015
  7. 3/7 strbuf: introduce strbuf_read_cmd helperJeff King, Mar 22, 2015
  8. Eric SunshineMar 22, 2015
  9. Junio C HamanoMar 22, 2015
  10. Junio C HamanoMar 22, 2015
  11. 0/7 introduce capture_command to avoid deadlocksJeff King, Mar 23, 2015
  12. 1/7 wt-status: don't flush before running "submodule status"Jeff King, Mar 23, 2015
  13. 2/7 wt_status: fix signedness mismatch in strbuf_read callJeff King, Mar 23, 2015
  14. 3/7 run-command: introduce capture_command helperJeff King, Mar 23, 2015
  15. 4/7 wt-status: use capture_commandJeff King, Mar 23, 2015
  16. 5/7 submodule: use capture_commandJeff King, Mar 23, 2015
  17. 6/7 trailer: use capture_commandJeff King, Mar 23, 2015
  18. 7/7 run-command: forbid using run_command with piped outputJeff King, Mar 23, 2015
  19. Junio C HamanoMar 23, 2015
  20. Jeff KingMar 22, 2015
  21. Junio C HamanoMar 22, 2015
  22. Jeff KingMar 22, 2015
  23. 4/7 wt-status: use strbuf_read_cmdJeff King, Mar 22, 2015
  24. 5/7 submodule: use strbuf_read_cmdJeff King, Mar 22, 2015
  25. 6/7 trailer: use strbuf_read_cmdJeff King, Mar 22, 2015
  26. 7/7 run-command: forbid using run_command with piped outputJeff King, Mar 22, 2015

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