[pacman-dev] [PATCH 3/5] llstat: modify path in place

[Andrew Gregory]

This makes llstat's signature differ from lstat's, but we never actually
use it on a const string and this saves a large number of strdup's.
This also allows stripping multiple trailing slashes and corrects a bug
where calling llstat on "/" would result in calling lstat on an empty
string.

Signed-off-by: Andrew Gregory <andrew.gregory.8 at gmail.com>
---
 src/common/util-common.c | 18 +++++++++++-------
 src/common/util-common.h |  2 +-
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/src/common/util-common.c b/src/common/util-common.c
index e6f9519..3316eae 100644
--- a/src/common/util-common.c
+++ b/src/common/util-common.c
@@ -80,17 +80,21 @@ char *mdirname(const char *path)
  * @param buf structure to fill with stat information
  * @return the return code from lstat
  */
-int llstat(const char *path, struct stat *buf)
+int llstat(char *path, struct stat *buf)
 {
 	int ret;
+	char *c = NULL;
 	size_t len = strlen(path);
 
-	/* strip the trailing slash if one exists */
-	if(len != 0 && path[len - 1] == '/') {
-		char *newpath = strdup(path);
-		newpath[len - 1] = '\0';
-		ret = lstat(newpath, buf);
-		free(newpath);
+	while(len > 1 && path[len - 1] == '/') {
+		--len;
+		c = path + len;
+	}
+
+	if(c) {
+		*c = '\0';
+		ret = lstat(path, buf);
+		*c = '/';
 	} else {
 		ret = lstat(path, buf);
 	}
diff --git a/src/common/util-common.h b/src/common/util-common.h
index 5f04b00..576702f 100644
--- a/src/common/util-common.h
+++ b/src/common/util-common.h
@@ -25,7 +25,7 @@
 const char *mbasename(const char *path);
 char *mdirname(const char *path);
 
-int llstat(const char *path, struct stat *buf);
+int llstat(char *path, struct stat *buf);
 
 #ifndef HAVE_STRNDUP
 char *strndup(const char *s, size_t n);
-- 
2.0.0