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[PATCH] use strchrnul() in place of strchr() and strlen()

From
RMRohit Mani <rohit.mani@outlook.com>
Date
Mar 5, 2014, 19:29 UTC
Message-ID
<BLU0-SMTP1988500CEC43BD4C57254AB91890@phx.gbl>
In-Reply-To
<y>

Avoid scanning strings twice, once with strchr() and then with strlen(), by using strchrnul(). Update the conditional expressions involving the return value of strchrnul() with a check for '\0'.

Signed-off-by: Rohit Mani <rohit.mani@outlook.com>
---
I plan to apply for the GSoC.
 archive.c        |    4 ++--
 cache-tree.c     |   16 +++++++---------
 diff.c           |    9 +++------
 fast-import.c    |   35 ++++++++++++++---------------------
 match-trees.c    |   11 ++++-------
 parse-options.c  |    5 +----
 pretty.c         |    5 ++---
 remote-testsvn.c |    4 ++--
 ws.c             |    7 ++-----
 9 files changed, 37 insertions(+), 59 deletions(-)
diff --git a/archive.c b/archive.c
index 346f3b2..d196215 100644
--- a/archive.c
+++ b/archive.c
@@ -259,8 +259,8 @@ static void parse_treeish_arg(const char **argv,
 	/* Remotes are only allowed to fetch actual refs */
 	if (remote) {
 		char *ref = NULL;
-		const char *colon = strchr(name, ':');
-		int refnamelen = colon ? colon - name : strlen(name);
+		const char *colon = strchrnul(name, ':');
+		int refnamelen = colon - name;
 
 		if (!dwim_ref(name, refnamelen, sha1, &ref))
 			die("no such ref: %.*s", refnamelen, name);
diff --git a/cache-tree.c b/cache-tree.c
index 0bbec43..21a13cf 100644
--- a/cache-tree.c
+++ b/cache-tree.c
@@ -121,11 +121,11 @@ void cache_tree_invalidate_path(struct cache_tree *it, const char *path)
 
 	if (!it)
 		return;
-	slash = strchr(path, '/');
+	slash = strchrnul(path, '/');
 	it->entry_count = -1;
-	if (!slash) {
+	if (*slash == '\0') {
 		int pos;
-		namelen = strlen(path);
+		namelen = slash - path;
 		pos = subtree_pos(it, path, namelen);
 		if (0 <= pos) {
 			cache_tree_free(&it->down[pos]->cache_tree);
@@ -554,9 +554,7 @@ static struct cache_tree *cache_tree_find(struct cache_tree *it, const char *pat
 		const char *slash;
 		struct cache_tree_sub *sub;
 
-		slash = strchr(path, '/');
-		if (!slash)
-			slash = path + strlen(path);
+		slash = strchrnul(path, '/');
 		/* between path and slash is the name of the
 		 * subtree to look for.
 		 */
@@ -564,10 +562,10 @@ static struct cache_tree *cache_tree_find(struct cache_tree *it, const char *pat
 		if (!sub)
 			return NULL;
 		it = sub->cache_tree;
-		if (slash)
-			while (*slash && *slash == '/')
+		if (*slash != '\0')
+			while (*slash != '\0' && *slash == '/')
 				slash++;
-		if (!slash || !*slash)
+		if (*slash == '\0' || !*slash)
 			return it; /* prefix ended with slashes */
 		path = slash;
 	}
diff --git a/diff.c b/diff.c
index e800666..83a039b 100644
--- a/diff.c
+++ b/diff.c
@@ -3365,14 +3365,11 @@ static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *va
 	if (c != '-')
 		return 0;
 	arg++;
-	eq = strchr(arg, '=');
-	if (eq)
-		len = eq - arg;
-	else
-		len = strlen(arg);
+	eq = strchrnul(arg, '=');
+	len = eq - arg;
 	if (!len || strncmp(arg, arg_long, len))
 		return 0;
-	if (eq) {
+	if (*eq != '\0') {
 		int n;
 		char *end;
 		if (!isdigit(*++eq))
diff --git a/fast-import.c b/fast-import.c
index 4fd18a3..449595d 100644
--- a/fast-import.c
+++ b/fast-import.c
@@ -1485,14 +1485,12 @@ static int tree_content_set(
 	unsigned int i, n;
 	struct tree_entry *e;
 
-	slash1 = strchr(p, '/');
-	if (slash1)
-		n = slash1 - p;
-	else
-		n = strlen(p);
+	slash1 = strchrnul(p, '/');
+	n = slash1 - p;
+
 	if (!n)
 		die("Empty path component found in input");
-	if (!slash1 && !S_ISDIR(mode) && subtree)
+	if (*slash1 == '\0' && !S_ISDIR(mode) && subtree)
 		die("Non-directories cannot have subtrees");
 
 	if (!root->tree)
@@ -1501,7 +1499,7 @@ static int tree_content_set(
 	for (i = 0; i < t->entry_count; i++) {
 		e = t->entries[i];
 		if (e->name->str_len == n && !strncmp_icase(p, e->name->str_dat, n)) {
-			if (!slash1) {
+			if (*slash1 == '\0') {
 				if (!S_ISDIR(mode)
 						&& e->versions[1].mode == mode
 						&& !hashcmp(e->versions[1].sha1, sha1))
@@ -1552,7 +1550,7 @@ static int tree_content_set(
 	e->versions[0].mode = 0;
 	hashclr(e->versions[0].sha1);
 	t->entries[t->entry_count++] = e;
-	if (slash1) {
+	if (*slash1 != '\0') {
 		e->tree = new_tree_content(8);
 		e->versions[1].mode = S_IFDIR;
 		tree_content_set(e, slash1 + 1, sha1, mode, subtree);
@@ -1576,11 +1574,8 @@ static int tree_content_remove(
 	unsigned int i, n;
 	struct tree_entry *e;
 
-	slash1 = strchr(p, '/');
-	if (slash1)
-		n = slash1 - p;
-	else
-		n = strlen(p);
+	slash1 = strchrnul(p, '/');
+	n = slash1 - p;
 
 	if (!root->tree)
 		load_tree(root);
@@ -1594,7 +1589,7 @@ static int tree_content_remove(
 	for (i = 0; i < t->entry_count; i++) {
 		e = t->entries[i];
 		if (e->name->str_len == n && !strncmp_icase(p, e->name->str_dat, n)) {
-			if (slash1 && !S_ISDIR(e->versions[1].mode))
+			if (*slash1 != '\0' && !S_ISDIR(e->versions[1].mode))
 				/*
 				 * If p names a file in some subdirectory, and a
 				 * file or symlink matching the name of the
@@ -1602,7 +1597,7 @@ static int tree_content_remove(
 				 * exist and need not be deleted.
 				 */
 				return 1;
-			if (!slash1 || !S_ISDIR(e->versions[1].mode))
+			if (*slash1 == '\0' || !S_ISDIR(e->versions[1].mode))
 				goto del_entry;
 			if (!e->tree)
 				load_tree(e);
@@ -1644,11 +1639,9 @@ static int tree_content_get(
 	unsigned int i, n;
 	struct tree_entry *e;
 
-	slash1 = strchr(p, '/');
-	if (slash1)
-		n = slash1 - p;
-	else
-		n = strlen(p);
+	slash1 = strchrnul(p, '/');
+	n = slash1 - p;
+
 	if (!n && !allow_root)
 		die("Empty path component found in input");
 
@@ -1664,7 +1657,7 @@ static int tree_content_get(
 	for (i = 0; i < t->entry_count; i++) {
 		e = t->entries[i];
 		if (e->name->str_len == n && !strncmp_icase(p, e->name->str_dat, n)) {
-			if (!slash1)
+			if (*slash1 == '\0')
 				goto found_entry;
 			if (!S_ISDIR(e->versions[1].mode))
 				return 0;
diff --git a/match-trees.c b/match-trees.c
index 7873cde..7cca0f6 100644
--- a/match-trees.c
+++ b/match-trees.c
@@ -182,13 +182,10 @@ static int splice_tree(const unsigned char *hash1,
 	enum object_type type;
 	int status;
 
-	subpath = strchr(prefix, '/');
-	if (!subpath)
-		toplen = strlen(prefix);
-	else {
-		toplen = subpath - prefix;
+	subpath = strchrnul(prefix, '/');
+	toplen = subpath - prefix;
+	if (*subpath != '\0')
 		subpath++;
-	}
 
 	buf = read_sha1_file(hash1, &type, &sz);
 	if (!buf)
@@ -215,7 +212,7 @@ static int splice_tree(const unsigned char *hash1,
 	if (!rewrite_here)
 		die("entry %.*s not found in tree %s",
 		    toplen, prefix, sha1_to_hex(hash1));
-	if (subpath) {
+	if (*subpath != '\0') {
 		status = splice_tree(rewrite_here, subpath, hash2, subtree);
 		if (status)
 			return status;
diff --git a/parse-options.c b/parse-options.c
index 7b8d3fa..a5fa0b8 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -223,13 +223,10 @@ static int parse_long_opt(struct parse_opt_ctx_t *p, const char *arg,
                           const struct option *options)
 {
 	const struct option *all_opts = options;
-	const char *arg_end = strchr(arg, '=');
+	const char *arg_end = strchrnul(arg, '=');
 	const struct option *abbrev_option = NULL, *ambiguous_option = NULL;
 	int abbrev_flags = 0, ambiguous_flags = 0;
 
-	if (!arg_end)
-		arg_end = arg + strlen(arg);
-
 	for (; options->type != OPTION_END; options++) {
 		const char *rest, *long_name = options->long_name;
 		int flags = 0, opt_flags = 0;
diff --git a/pretty.c b/pretty.c
index 87db08b..b1f60f9 100644
--- a/pretty.c
+++ b/pretty.c
@@ -549,14 +549,13 @@ static char *get_header(const struct commit *commit, const char *msg,
 	const char *line = msg;
 
 	while (line) {
-		const char *eol = strchr(line, '\n'), *next;
+		const char *eol = strchrnul(line, '\n'), *next;
 
 		if (line == eol)
 			return NULL;
-		if (!eol) {
+		if (*eol == '\0') {
 			warning("malformed commit (header is missing newline): %s",
 				sha1_to_hex(commit->object.sha1));
-			eol = line + strlen(line);
 			next = NULL;
 		} else
 			next = eol + 1;
diff --git a/remote-testsvn.c b/remote-testsvn.c
index 078f1ff..6be55cb 100644
--- a/remote-testsvn.c
+++ b/remote-testsvn.c
@@ -78,8 +78,8 @@ static int parse_rev_note(const char *msg, struct rev_note *res)
 	size_t len;
 
 	while (*msg) {
-		end = strchr(msg, '\n');
-		len = end ? end - msg : strlen(msg);
+		end = strchrnul(msg, '\n');
+		len = end - msg;
 
 		key = "Revision-number: ";
 		if (starts_with(msg, key)) {
diff --git a/ws.c b/ws.c
index b498d75..ea4b2b1 100644
--- a/ws.c
+++ b/ws.c
@@ -33,11 +33,8 @@ unsigned parse_whitespace_rule(const char *string)
 		int negated = 0;
 
 		string = string + strspn(string, ", \t\n\r");
-		ep = strchr(string, ',');
-		if (!ep)
-			len = strlen(string);
-		else
-			len = ep - string;
+		ep = strchrnul(string, ',');
+		len = ep - string;
 
 		if (*string == '-') {
 			negated = 1;

-- 
1.7.9.5
Previous: Elia PintoNext: Junio C Hamano
Message 69 of 98 in “Close a forgotten reference to the HEAD ref.”
  1. 1/2 Close a forgotten reference to the HEAD ref.Robin Rosenberg, Dec 2, 2008
  2. 2/2 Improve closing of files in error situations.Robin Rosenberg, Dec 2, 2008
  3. 2/2 Improve closing of files in error situations.Robin Rosenberg, Dec 2, 2008
  4. 0/3 Ref log readerRobin Rosenberg, Jun 7, 2009
  5. 1/3 Assert the name and origName properties of Ref objectsRobin Rosenberg, Jun 7, 2009
  6. 2/3 Add methods to RawParseUtils for scanning backwards.Robin Rosenberg, Jun 7, 2009
  7. 3/3 Add a ref log reader classRobin Rosenberg, Jun 7, 2009
  8. Shawn O. PearceJun 7, 2009
  9. Robin RosenbergJun 7, 2009
  10. Shawn O. PearceJun 7, 2009
  11. 1/2 Add methods to RawParseUtils for scanning backwards.Robin Rosenberg, Jun 8, 2009
  12. 2/2 Add a ref log reader classRobin Rosenberg, Jun 8, 2009
  13. Shawn O. PearceJun 12, 2009
  14. 1/2 Use a UTC relative time zone for PersonIdentRobin Rosenberg, Jun 15, 2009
  15. 2/2 Add a ref log reader classRobin Rosenberg, Jun 15, 2009
  16. Robin RosenbergJun 15, 2009
  17. [BUG] apply: test for trailing whitespace & no new line bugy@vger.kernel.org, Jun 22, 2009
  18. [BUG] apply: test for trailing whitespace & no new line bugy@vger.kernel.org, Jun 22, 2009
  19. diff.c: fix a graph output bugstruggleyb.nku@gmail.com, Jul 8, 2010
  20. Junio C HamanoJul 9, 2010
  21. Junio C HamanoJul 9, 2010
  22. Nazri RamliyJul 9, 2010
  23. Junio C HamanoJul 9, 2010
  24. Bo YangJul 11, 2010
  25. 1/2 setup.c: add enter_work_tree()pclouds@gmail.com, Oct 7, 2010
  26. 2/2 worktree: provide better prefix to go back to original cwdpclouds@gmail.com, Oct 7, 2010
  27. Nguyen Thai Ngoc DuyOct 7, 2010
  28. Junio C HamanoOct 7, 2010
  29. Nguyen Thai Ngoc DuyOct 7, 2010
  30. Junio C HamanoOct 7, 2010
  31. Nguyen Thai Ngoc DuyOct 7, 2010
  32. Corrected cmitmode set in the right lower window when initiating a diff.Michał Pomorski, Nov 23, 2010
  33. git-p4: replace each tab with 8 spaces for consistencyAndrew Garber, Apr 7, 2011
  34. Junio C HamanoApr 7, 2011
  35. Phil HordApr 7, 2011
  36. Junio C HamanoApr 7, 2011
  37. git-p4: replace each tab with 8 spaces for consistencyAndrew Garber, Apr 7, 2011
  38. file import functionality for git-remote-mwPavel Volek, Jun 4, 2012
  39. Matthieu MoyJun 4, 2012
  40. Export file attachements in git-remote-mediawikiNGUYEN Kim Thuat, Jun 4, 2012
  41. Matthieu MoyJun 4, 2012
  42. nguyenkiJun 5, 2012
  43. Matthieu MoyJun 5, 2012
  44. nguyenkiJun 6, 2012
  45. nguyenkiJun 5, 2012
  46. [PATCHv1] Export file in git-remote-mediawikiKim Thuat NGUYEN, Jun 8, 2012
  47. Matthieu MoyJun 8, 2012
  48. nguyenkiJun 8, 2012
  49. Matthieu MoyJun 10, 2012
  50. [PATCHv2] git-remote-mediawiki: export File: attachmentsKim Thuat NGUYEN, Jun 12, 2012
  51. Matthieu MoyJun 12, 2012
  52. nguyenkiJun 12, 2012
  53. Max HornJun 12, 2012
  54. [PATCHv3] git-remote-mediawiki: export File: attachmentskim-thuat.nguyen@ensimag.imag.fr, Jun 13, 2012
  55. Matthieu MoyJun 13, 2012
  56. git send-email should not allow 'y' for in-reply-toEric Blake, Jan 11, 2013
  57. Jeff KingJan 11, 2013
  58. Eric BlakeJan 11, 2013
  59. Hilco WijbengaJan 11, 2013
  60. Jeff KingJan 11, 2013
  61. Junio C HamanoFeb 24, 2013
  62. v3 [PATCH 1/2] status: introduce status.short to enable --short by defaulty@ensimag.imag.fr, Jun 10, 2013
  63. v3 [PATCH 1/2] status: introduce status.short to enable --short by defaulty@ensimag.imag.fr, Jun 10, 2013
  64. v3 [PATCH 2/2] status:introduce status.branch to enable --branch by defaulty@ensimag.imag.fr, Jun 10, 2013
  65. v3 [PATCH 2/2] status:introduce status.branch to enable --branch by defaulty@ensimag.imag.fr, Jun 10, 2013
  66. Matthieu MoyJun 10, 2013
  67. Junio C HamanoJun 10, 2013
  68. 3/3 builtin/blame.c: reduce scope of variablesElia Pinto, Jan 29, 2014
  69. use strchrnul() in place of strchr() and strlen()Rohit Mani, Mar 5, 2014
  70. Junio C HamanoMar 6, 2014
  71. [GSoC][PATCH v2] use strchrnul() in place of strchr() and strlen()Rohit Mani, Mar 8, 2014
  72. Junio C HamanoMar 10, 2014
  73. [GSOC2014]TamerTas, Mar 10, 2014
  74. [GSOC2014] changed logical chain in branch.c to lookup tablesTamerTas, Mar 10, 2014
  75. Stefan BellerMar 10, 2014
  76. Eric SunshineMar 10, 2014
  77. Tamer TASMar 10, 2014
  78. Eric SunshineMar 10, 2014
  79. Tamer TASMar 11, 2014
  80. Eric SunshineMar 11, 2014
  81. [GSOC2014] add: Rewrite run_add_interactive to use struct argv_arrayMovchan Pavel, Mar 18, 2014
  82. Junio C HamanoMar 18, 2014
  83. Use "working tree" instead of "working directory" for git statusLars Vogel, Jun 9, 2016
  84. Eric SunshineJun 9, 2016
  85. Lars VogelJun 9, 2016
  86. 1/1 git-stash.txt: correct "git stash" behavior with no argumentsTakahito Ogawa, Oct 11, 2017
  87. Junio C HamanoOct 12, 2017
  88. 小川恭史Oct 12, 2017
  89. 小川恭史Oct 12, 2017
  90. Junio C HamanoOct 12, 2017
  91. Allow usage of --gpg-sign flag in commit-tree builtin.Brandon Richardson, Jan 17, 2019
  92. Martin ÅgrenJan 17, 2019
  93. commit-tree: add missing --gpg-sign flagBrandon Richardson, Jan 18, 2019
  94. Martin ÅgrenJan 18, 2019
  95. Brandon RichardsonJan 18, 2019
  96. Junio C HamanoJan 18, 2019
  97. [L10N] Kickoff for Git 2.22.0 round #1Jiang Xin, May 14, 2019
  98. [L10N] Kickoff for Git 2.49.0Jiang Xin, Feb 27, 2025

Read the whole thread, see it on lore, or plain text.

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