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[PATCH] Diff: two fixes.

From
Junio C Hamano <junkio@cox.net>
Date
May 28, 2005, 19:22 UTC
Message-ID
<7vr7frrw8x.fsf_-_@assigned-by-dhcp.cox.net>
In-Reply-To
<7vis13wth4.fsf_-_@assigned-by-dhcp.cox.net>

The count-delta routine sometimes overcounted the copied source material which resulted in unsigned int wraparound.

The latest diff-cache (uncached) fix to eliminate empty diffs from the output revealed that is_exact_match() was not careful enough, which resulted in a sanity check routine triggering when a file is added to an index.

Signed-off-by: Junio C Hamano <junkio@cox.net>
---

count-delta.c | 3 +++ diff.c | 3 +++ 2 files changed, 6 insertions(+)

diff --git a/count-delta.c b/count-delta.c
--- a/count-delta.c
+++ b/count-delta.c
@@ -88,5 +88,8 @@ unsigned long count_delta(void *delta_bu
 	/* delete size is what was _not_ copied from source.
 	 * edit size is that and literal additions.
 	 */
+	if (src_size + added_literal < copied_from_source)
+		/* we ended up overcounting and underflowed */
+		return 0;
 	return (src_size - copied_from_source) + added_literal;
 }
diff --git a/diff.c b/diff.c
--- a/diff.c
+++ b/diff.c
@@ -689,6 +689,9 @@ int is_exact_match(struct diff_filespec 
 	if (src->sha1_valid && dst->sha1_valid &&
 	    !memcmp(src->sha1, dst->sha1, 20))
 		return 1;
+	/* if either is invalid they cannot match */
+	if (!DIFF_FILE_VALID(src) || !DIFF_FILE_VALID(dst))
+		return 0;
 	if (diff_populate_filespec(src, 1) || diff_populate_filespec(dst, 1))
 		return 0;
 	if (src->size != dst->size)
------------------------------------------------
Previous: Junio C HamanoNext: Junio C Hamano
Message 24 of 45 in “Broken directory pathname pruning..”
  1. Linus TorvaldsMay 27, 2005
  2. Junio C HamanoMay 27, 2005
  3. allow pathspec to end with a slashJunio C Hamano, May 27, 2005
  4. allow pathspec to end with a slash (take #2)Junio C Hamano, May 27, 2005
  5. Diff updates, fixing pathspec and rename/copy interaction.Junio C Hamano, May 27, 2005
  6. Linus TorvaldsMay 27, 2005
  7. Junio C HamanoMay 27, 2005
  8. 00/12 Diff updatesJunio C Hamano, May 27, 2005
  9. 01/12 Fix math thinko in similarity estimator.Junio C Hamano, May 27, 2005
  10. 02/12 Introduce diff_free_filepair() funcion.Junio C Hamano, May 27, 2005
  11. 03/12 Make pathspec only care about the detination tree.Junio C Hamano, May 27, 2005
  12. 04/12 Remove unused rank field from diff_core structure.Junio C Hamano, May 27, 2005
  13. 05/12 Do not expose internal scaling to diff-helper.Junio C Hamano, May 27, 2005
  14. 06/12 Remove final newline from the value of xfrm_msg variable.Junio C Hamano, May 27, 2005
  15. 07/12 Clean up diff_setup() to make it more extensible.Junio C Hamano, May 27, 2005
  16. 08/12 Remove a function not used anymore.Junio C Hamano, May 27, 2005
  17. 09/12 Add --pickaxe-all to diff-* brothers.Junio C Hamano, May 27, 2005
  18. 10/12 Fix the way diffcore-rename records unremoved source.Junio C Hamano, May 27, 2005
  19. 11/12 Move pathspec to the beginning of the diffcore chain.Junio C Hamano, May 27, 2005
  20. 12/12 Optimize diff-tree -[CM] --stdinJunio C Hamano, May 27, 2005
  21. Yoichi YuasaJun 4, 2005
  22. Junio C HamanoMay 27, 2005
  23. Do not show empty diff in diff-cache uncached.Junio C Hamano, May 28, 2005
  24. Diff: two fixes.Junio C Hamano, May 28, 2005
  25. diff-helper: fix R/C score parsing under -z flag.Junio C Hamano, May 29, 2005
  26. diff-cache: diff-patch (-p) format fixes.Junio C Hamano, May 29, 2005
  27. diff: code clean-up.Junio C Hamano, May 29, 2005
  28. Linus TorvaldsMay 29, 2005
  29. Junio C HamanoMay 29, 2005
  30. Junio C HamanoMay 29, 2005
  31. 0/3 Leftover bits after 12-seriesJunio C Hamano, May 29, 2005
  32. 1/3 diff-helper: Fix R/C score parsing under -z flag.Junio C Hamano, May 29, 2005
  33. 2/3 diff: consolidate various calls into diffcore.Junio C Hamano, May 29, 2005
  34. 3/3 diff: code clean-up and removal of rename hack.Junio C Hamano, May 29, 2005
  35. 0/4 Junio C Hamano, May 30, 2005
  36. 1/4 diff: further cleanup.Junio C Hamano, May 30, 2005
  37. 2/4 diff: fix the culling of unneeded delete record.Junio C Hamano, May 30, 2005
  38. 3/4 Add -B flag to diff-* brothers.Junio C Hamano, May 30, 2005
  39. 4/4 Add -O<orderfile> option to diff-* brothers.Junio C Hamano, May 30, 2005
  40. Linus TorvaldsMay 30, 2005
  41. Junio C HamanoMay 30, 2005
  42. apply.c: tolerate diff from a dirty but unchanged pathJunio C Hamano, Jun 11, 2005
  43. Linus TorvaldsJun 12, 2005
  44. Linus TorvaldsJun 12, 2005
  45. Junio C HamanoJun 12, 2005

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