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[PATCH] system_path: use a static buffer

From
Carlos Martín Nieto <cmn@elego.de>
Date
Mar 17, 2011, 14:24 UTC
Message-ID
<1300371853-8965-1-git-send-email-cmn@elego.de>
In-Reply-To
<1300359664-6230-1-git-send-email-cmn@elego.de>

Make system_path behave like the other path functions by using a static buffer, fixing a memory leak.

Also make sure the prefix pointer is always initialized to either PREFIX or NULL.

git_etc_gitattributes and git_etc_gitconfig are the only users who are affected by this change. Make them use a static buffer, which fits their use better as well.

Signed-off-by: Carlos Martín Nieto <cmn@elego.de>
---

It was pointed out that one should always check for an encoding error (-1) with the printf family. I'm not sure how likely this is to happen, but this should make the code extra portable :)

 attr.c     |    6 +++---
 config.c   |    6 +++---
 exec_cmd.c |   15 ++++++++++-----
 3 files changed, 16 insertions(+), 11 deletions(-)
diff --git a/attr.c b/attr.c
index 6aff695..64d803f 100644
--- a/attr.c
+++ b/attr.c
@@ -467,9 +467,9 @@ static void drop_attr_stack(void)
 
 const char *git_etc_gitattributes(void)
 {
-	static const char *system_wide;
-	if (!system_wide)
-		system_wide = system_path(ETC_GITATTRIBUTES);
+	static char system_wide[PATH_MAX];
+	if (!system_wide[0])
+		strlcpy(system_wide, system_path(ETC_GITATTRIBUTES), PATH_MAX);
 	return system_wide;
 }
 
diff --git a/config.c b/config.c
index 822ef83..cd1c295 100644
--- a/config.c
+++ b/config.c
@@ -808,9 +808,9 @@ int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 
 const char *git_etc_gitconfig(void)
 {
-	static const char *system_wide;
-	if (!system_wide)
-		system_wide = system_path(ETC_GITCONFIG);
+	static char system_wide[PATH_MAX];
+	if (!system_wide[0])
+		strlcpy(system_wide, system_path(ETC_GITCONFIG), PATH_MAX);
 	return system_wide;
 }
 
diff --git a/exec_cmd.c b/exec_cmd.c
index 38545e8..35d5cd8 100644
--- a/exec_cmd.c
+++ b/exec_cmd.c
@@ -9,11 +9,12 @@ static const char *argv0_path;
 const char *system_path(const char *path)
 {
 #ifdef RUNTIME_PREFIX
-	static const char *prefix;
+	static const char *prefix = NULL;
 #else
 	static const char *prefix = PREFIX;
 #endif
-	struct strbuf d = STRBUF_INIT;
+	static char buf[PATH_MAX];
+	int ret;
 
 	if (is_absolute_path(path))
 		return path;
@@ -33,9 +34,13 @@ const char *system_path(const char *path)
 	}
 #endif
 
-	strbuf_addf(&d, "%s/%s", prefix, path);
-	path = strbuf_detach(&d, NULL);
-	return path;
+	ret = snprintf(buf, sizeof(buf), "%s/%s", prefix, path);
+	if (ret >= sizeof(buf))
+		die("system path too long for %s", path);
+	else if (ret < 0)
+		die_errno("encoding error");
+
+	return buf;
 }
 
 const char *git_extract_argv0_path(const char *argv0)
-- 
1.7.4.1
Previous: Carlos Martín NietoNext: Junio C Hamano
Message 25 of 48 in “Fix some errors reported by valgrind”
  1. 0/3 Fix some errors reported by valgrindCarlos Martín Nieto, Mar 14, 2011
  2. 1/3 make_absolute_path: Don't try to copy a string to itselfCarlos Martín Nieto, Mar 14, 2011
  3. Jeff KingMar 14, 2011
  4. Junio C HamanoMar 14, 2011
  5. Carlos Martín NietoMar 14, 2011
  6. Junio C HamanoMar 14, 2011
  7. Carlos Martín NietoMar 15, 2011
  8. Carlos Martín NietoMar 15, 2011
  9. Junio C HamanoMar 15, 2011
  10. Carlos Martín NietoMar 15, 2011
  11. Nguyen Thai Ngoc DuyMar 16, 2011
  12. Carlos Martín NietoMar 16, 2011
  13. Nguyen Thai Ngoc DuyMar 16, 2011
  14. Nguyen Thai Ngoc DuyMar 16, 2011
  15. Carlos Martín NietoMar 16, 2011
  16. 2/3 setup_path(): Free temporary bufferCarlos Martín Nieto, Mar 14, 2011
  17. Jeff KingMar 14, 2011
  18. Carlos Martín NietoMar 14, 2011
  19. system_path: use a static bufferCarlos Martín Nieto, Mar 16, 2011
  20. Erik Faye-LundMar 16, 2011
  21. Carlos Martín NietoMar 16, 2011
  22. system_path: use a static bufferCarlos Martín Nieto, Mar 16, 2011
  23. Junio C HamanoMar 16, 2011
  24. system_path: use a static bufferCarlos Martín Nieto, Mar 17, 2011
  25. system_path: use a static bufferCarlos Martín Nieto, Mar 17, 2011
  26. Junio C HamanoMar 18, 2011
  27. Carlos Martín NietoMar 21, 2011
  28. Jeff KingMar 21, 2011
  29. Carlos Martín NietoMar 21, 2011
  30. Jeff KingMar 21, 2011
  31. Carlos Martín NietoMar 21, 2011
  32. Nguyen Thai Ngoc DuyMar 18, 2011
  33. PATH_MAX (Re: [PATCH] system_path: use a static buffer)Jonathan Nieder, Mar 18, 2011
  34. Nguyen Thai Ngoc DuyMar 18, 2011
  35. Carlos Martín NietoMar 21, 2011
  36. Lasse MakholmMar 21, 2011
  37. Nguyen Thai Ngoc DuyMar 21, 2011
  38. 1/2 wrapper.c: add xgetcwd()Nguyễn Thái Ngọc Duy, Mar 18, 2011
  39. 2/2 setup_gently: use xgetcwd()Nguyễn Thái Ngọc Duy, Mar 18, 2011
  40. Junio C HamanoMar 14, 2011
  41. Carlos Martín NietoMar 14, 2011
  42. Jeff KingMar 15, 2011
  43. t/README: Add a note about running commands under valgrindCarlos Martín Nieto, Mar 15, 2011
  44. Junio C HamanoMar 15, 2011
  45. Carlos Martín NietoMar 15, 2011
  46. 3/3 clone: Free a few pathsCarlos Martín Nieto, Mar 14, 2011
  47. Jonathan NiederMar 14, 2011
  48. Junio C HamanoMar 18, 2011

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