From: Karel Zak <kzak@redhat.com>
Date: Wed, 28 Jul 2010 13:16:49 +0000 (+0200)
Subject: libmount: improve mnt_get_fs_root() and mnt_get_mountpoint()
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9758c88ad19c7aa27d2077738729afcbce58bfc3;p=util-linux

libmount: improve mnt_get_fs_root() and mnt_get_mountpoint()

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/shlibs/mount/src/mountP.h b/shlibs/mount/src/mountP.h
index 59ffb94e..ea6a87c5 100644
--- a/shlibs/mount/src/mountP.h
+++ b/shlibs/mount/src/mountP.h
@@ -37,6 +37,8 @@
 #define DEBUG_OPTIONS	(1 << 3)
 #define DEBUG_LOCKS	(1 << 4)
 #define DEBUG_TAB	(1 << 5)
+#define DEBUG_MTAB	(1 << 6)
+#define DEBUG_UTILS	(1 << 7)
 #define DEBUG_ALL	0xFFFF
 
 #ifdef CONFIG_LIBMOUNT_DEBUG
@@ -74,7 +76,7 @@ extern char *mnt_get_username(const uid_t uid);
 extern int mnt_has_regular_mtab(void);
 
 extern char *mnt_get_mountpoint(const char *path);
-extern char *mnt_get_fs_root(const char *path);
+extern char *mnt_get_fs_root(const char *path, const char *mountpoint);
 
 /*
  * Generic iterator
diff --git a/shlibs/mount/src/utils.c b/shlibs/mount/src/utils.c
index da2799b5..55e06058 100644
--- a/shlibs/mount/src/utils.c
+++ b/shlibs/mount/src/utils.c
@@ -381,7 +381,7 @@ char *mnt_get_mountpoint(const char *path)
 	if (!mnt)
 		return NULL;
 	if (*mnt == '/' && *(mnt + 1) == '\0')
-		return mnt;				/* root fs */
+		goto done;
 
 	if (stat(mnt, &st))
 		goto err;
@@ -397,31 +397,37 @@ char *mnt_get_mountpoint(const char *path)
 		dir = st.st_dev;
 		if (dir != base) {
 			*(p - 1) = '/';
-			return mnt;
+			goto done;
 		}
 		base = dir;
 	} while (mnt && *(mnt + 1) != '\0');
 
 	memcpy(mnt, "/", 2);
-	return mnt;		/* root fs */
+done:
+	DBG(DEBUG_UTILS, fprintf(stderr,
+		"libmount: utils: fs-root for %s is %s\n", path, mnt));
+	return mnt;
 err:
 	free(mnt);
 	return NULL;
 }
 
-char *mnt_get_fs_root(const char *path)
+char *mnt_get_fs_root(const char *path, const char *mnt)
 {
-	char *mnt = mnt_get_mountpoint(path);
+	char *m = (char *) mnt;
 	const char *p;
 	size_t sz;
 
-	if (!mnt)
+	if (!m)
+		m = mnt_get_mountpoint(path);
+	if (!m)
 		return NULL;
 
-	sz = strlen(mnt);
+	sz = strlen(m);
 	p = sz > 1 ? path + sz : path;
 
-	free(mnt);
+	if (m != mnt)
+		free(m);
 
 	return *p ? strdup(p) : strdup("/");
 }