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[PATCH 07/10] reset: free allocated tree buffers

From
Jeff King <peff@peff.net>
Date
Sep 5, 2017, 13:04 UTC
Message-ID
<20170905130450.fsoglfwieei2ruir@sigill.intra.peff.net>
In-Reply-To
<20170905130149.agc3zp3s6i6e5aki@sigill.intra.peff.net>

We read the tree objects with fill_tree_descriptor(), but never actually free the resulting buffers, causing a memory leak. This isn't a huge deal because we call this code at most twice per program invocation. But it does potentially double our heap usage if you have large root trees. Let's free the trees before returning.

Signed-off-by: Jeff King <peff@peff.net>
---
Actually, in the two-call case we repeat one of the trees,
so we _could_ in theory stash it away. But we don't do that
currently, and it's probably not worth the effort. My main
motivation is just shutting up the leak checker so I can
find actual important leaks.
 builtin/reset.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)
diff --git a/builtin/reset.c b/builtin/reset.c
index 34839db8ca..9e22b4a1dc 100644
--- a/builtin/reset.c
+++ b/builtin/reset.c
@@ -44,10 +44,11 @@ static inline int is_merge(void)
 
 static int reset_index(const struct object_id *oid, int reset_type, int quiet)
 {
-	int nr = 0;
+	int i, nr = 0;
 	struct tree_desc desc[2];
 	struct tree *tree;
 	struct unpack_trees_options opts;
+	int ret = -1;
 
 	memset(&opts, 0, sizeof(opts));
 	opts.head_idx = 1;
@@ -81,19 +82,26 @@ static int reset_index(const struct object_id *oid, int reset_type, int quiet)
 		opts.fn = twoway_merge;
 	}
 
-	if (!fill_tree_descriptor(desc + nr, oid))
-		return error(_("Failed to find tree of %s."), oid_to_hex(oid));
+	if (!fill_tree_descriptor(desc + nr, oid)) {
+		error(_("Failed to find tree of %s."), oid_to_hex(oid));
+		goto out;
+	}
 	nr++;
 
-	if (unpack_trees(nr, desc, &opts))
-		return -1;
+	if (unpack_trees(nr, desc, &opts)) 
+		goto out;
 
 	if (reset_type == MIXED || reset_type == HARD) {
 		tree = parse_tree_indirect(oid);
 		prime_cache_tree(&the_index, tree);
 	}
 
-	return 0;
+	ret = 0;
+
+out:
+	for (i = 0; i < nr; i++)
+		free((void *)desc[i].buffer);
+	return ret;
 }
 
 static void print_new_head_line(struct commit *commit)
-- 
2.14.1.721.gc5bc1565f1
Previous: Jeff KingNext: Jeff King
Message 8 of 42 in “towards clean leak-checker output”
  1. 0/10 towards clean leak-checker outputJeff King, Sep 5, 2017
  2. 01/10 test-lib: --valgrind should not override --verbose-logJeff King, Sep 5, 2017
  3. 02/10 test-lib: set LSAN_OPTIONS to abort by defaultJeff King, Sep 5, 2017
  4. 03/10 add: free leaked pathspec after add_files_to_cache()Jeff King, Sep 5, 2017
  5. 04/10 update-index: fix cache entry leak in add_one_file()Jeff King, Sep 5, 2017
  6. 05/10 config: plug user_config leakJeff King, Sep 5, 2017
  7. 06/10 reset: make tree counting less confusingJeff King, Sep 5, 2017
  8. 07/10 reset: free allocated tree buffersJeff King, Sep 5, 2017
  9. 08/10 repository: free fields before overwriting themJeff King, Sep 5, 2017
  10. 09/10 set_git_dir: handle feeding gitdir to itselfJeff King, Sep 5, 2017
  11. Brandon WilliamsSep 7, 2017
  12. 10/10 add UNLEAK annotation for reducing leak false positivesJeff King, Sep 5, 2017
  13. Stefan BellerSep 5, 2017
  14. Jeff KingSep 7, 2017
  15. Stefan BellerSep 7, 2017
  16. Kaartic SivaraamSep 12, 2017
  17. Jeff KingSep 12, 2017
  18. Kaartic SivaraamSep 13, 2017
  19. Martin ÅgrenSep 6, 2017
  20. Jeff KingSep 7, 2017
  21. Kaartic SivaraamSep 12, 2017
  22. Jeff KingSep 12, 2017
  23. Kaartic SivaraamSep 13, 2017
  24. Martin ÅgrenSep 5, 2017
  25. Jeff KingSep 5, 2017
  26. Martin ÅgrenSep 5, 2017
  27. Jeff KingSep 6, 2017
  28. Junio C HamanoSep 6, 2017
  29. 0/2 simplifying !RUNTIME_PREFIXJeff King, Sep 6, 2017
  30. 1/2 system_path: move RUNTIME_PREFIX to a sub-functionJeff King, Sep 6, 2017
  31. Johannes SchindelinSep 6, 2017
  32. Jeff KingSep 6, 2017
  33. 2/2 git_extract_argv0_path: do nothing without RUNTIME_PREFIXJeff King, Sep 6, 2017
  34. 10/10 add UNLEAK annotation for reducing leak false positivesJeff King, Sep 8, 2017
  35. Jonathan TanSep 19, 2017
  36. Jeff KingSep 19, 2017
  37. git-compat-util: make UNLEAK less error-proneJonathan Tan, Sep 19, 2017
  38. Jeff KingSep 19, 2017
  39. git-compat-util: make UNLEAK less error-proneJonathan Tan, Sep 19, 2017
  40. Junio C HamanoSep 20, 2017
  41. Jeff KingSep 20, 2017
  42. Junio C HamanoSep 20, 2017

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