cluster: STABLE3 - libgfs2: Remove 'die' calls from __get_sysfs

[Andrew Price <andyp at fedoraproject dot org>]

Gitweb:        http://git.fedorahosted.org/git/cluster.git?p=cluster.git;a=commitdiff;h=b4fdfead0d853edbf37dfdb5b96649caa6dc33be
Commit:        b4fdfead0d853edbf37dfdb5b96649caa6dc33be
Parent:        fb37e5ab6be596f09bef22cdf28f68e4154c1d82
Author:        Andrew Price <andy@andrewprice.me.uk>
AuthorDate:    Thu Mar 19 16:11:28 2009 +0000
Committer:     Andrew Price <andy@andrewprice.me.uk>
CommitterDate: Thu Mar 19 18:12:41 2009 +0000

libgfs2: Remove 'die' calls from __get_sysfs

This patch removes the calls to die from __get_sysfs and adds error
handling to it and its callers. To enable this, the prototype of
get_sysfs_uint had to be changed so that error status can be returned.
Callers to get_sysfs and get_sysfs_uint are also updated to handle error
cases where appropriate.

Signed-off-by: Andrew Price <andy@andrewprice.me.uk>
---
 gfs2/libgfs2/libgfs2.h |    2 +-
 gfs2/libgfs2/misc.c    |   43 +++++++++++++++++++++++++++++++++----------
 gfs2/tool/df.c         |   44 +++++++++++++++++++++++++++++++-------------
 gfs2/tool/tune.c       |   10 ++++++++--
 4 files changed, 73 insertions(+), 26 deletions(-)

diff --git a/gfs2/libgfs2/libgfs2.h b/gfs2/libgfs2/libgfs2.h
index 2e79ad4..d8faf45 100644
--- a/gfs2/libgfs2/libgfs2.h
+++ b/gfs2/libgfs2/libgfs2.h
@@ -634,7 +634,7 @@ extern char *find_debugfs_mount(void);
 extern char *mp2fsname(char *mp);
 extern char *mp2fsname2(char *devname);
 extern char *get_sysfs(char *fsname, char *filename);
-extern unsigned int get_sysfs_uint(char *fsname, char *filename);
+extern int get_sysfs_uint(char *fsname, char *filename, unsigned int *val);
 extern int set_sysfs(char *fsname, char *filename, char *val);
 extern int is_fsname(char *name);
 
diff --git a/gfs2/libgfs2/misc.c b/gfs2/libgfs2/misc.c
index 320ce84..60b2d4f 100644
--- a/gfs2/libgfs2/misc.c
+++ b/gfs2/libgfs2/misc.c
@@ -216,10 +216,12 @@ static char *__get_sysfs(char *fsname, char *filename)
 
 	fd = open(path, O_RDONLY);
 	if (fd < 0)
-		die("can't open %s: %s\n", path, strerror(errno));
+		return NULL;
 	rv = read(fd, sysfs_buf, PAGE_SIZE);
-	if (rv < 0)
-		die("can't read from %s: %s\n", path, strerror(errno));
+	if (rv < 0) {
+		close(fd);
+		return NULL;
+	}
 
 	close(fd);
 	return sysfs_buf;
@@ -227,17 +229,30 @@ static char *__get_sysfs(char *fsname, char *filename)
 
 char *get_sysfs(char *fsname, char *filename)
 {
-	char *p = strchr(__get_sysfs(fsname, filename), '\n');
+	char *s;
+	char *p;
+
+	s = __get_sysfs(fsname, filename);
+	if (!s)
+		return NULL;
+	p = strchr(s, '\n');
 	if (p)
 		*p = '\0';
 	return sysfs_buf;
 }
 
-unsigned int get_sysfs_uint(char *fsname, char *filename)
+int get_sysfs_uint(char *fsname, char *filename, unsigned int *val)
 {
-	unsigned int x;
-	sscanf(__get_sysfs(fsname, filename), "%u", &x);
-	return x;
+	char *s = __get_sysfs(fsname, filename);
+	int ret;
+	if (!s)
+		return -1;
+	ret = sscanf(s, "%u", val);
+	if (1 != ret) {
+		errno = ENOMSG;
+		return -1;
+	}
+	return 0;
 }
 
 int set_sysfs(char *fsname, char *filename, char *val)
@@ -313,6 +328,7 @@ mp2fsname2(char *mp)
 	char buffer[PATH_MAX], device_name[PATH_MAX];
 	int fsdump, fspass, ret, found = 0;
 	char fspath[PATH_MAX], fsoptions[PATH_MAX], fstype[80];
+	char *id;
 
 	/* Take care of trailing '/' */
 	if (mp[strlen(mp) - 1] == '/')
@@ -361,7 +377,10 @@ mp2fsname2(char *mp)
 		if (de->d_name[0] == '.')
 			continue;
 
-		if (strcmp(get_sysfs(de->d_name, "id"), device_id) == 0) {
+		id = get_sysfs(de->d_name, "id");
+		if (!id)
+			continue;
+		if (strcmp(id, device_id) == 0) {
 			fsname = strdup(de->d_name);
 			break;
 		}
@@ -399,6 +418,7 @@ char *mp2fsname(char *mp)
 	struct stat statbuf;
 	DIR *d;
 	struct dirent *de;
+	char *id;
 
 	if (stat(mp, &statbuf))
 		return NULL;
@@ -415,7 +435,10 @@ char *mp2fsname(char *mp)
 		if (de->d_name[0] == '.')
 			continue;
 
-		if (strcmp(get_sysfs(de->d_name, "id"), device_id) == 0) {
+		id = get_sysfs(de->d_name, "id");
+		if (!id)
+			continue;
+		if (strcmp(id, device_id) == 0) {
 			fsname = strdup(de->d_name);
 			break;
 		}
diff --git a/gfs2/tool/df.c b/gfs2/tool/df.c
index 7d2875d..c817813 100644
--- a/gfs2/tool/df.c
+++ b/gfs2/tool/df.c
@@ -147,22 +147,40 @@ do_df_one(char *path)
 	printf("  Block size = %u\n", sbd.sd_sb.sb_bsize);
 	printf("  Journals = %u\n", journals);
 	printf("  Resource Groups = %"PRIu64"\n", rgrps);
-	printf("  Mounted lock proto = \"%s\"\n",
-	       ((value = get_sysfs(fs, "args/lockproto"))[0])
-	       ? value : sbd.sd_sb.sb_lockproto);
-	printf("  Mounted lock table = \"%s\"\n",
-	       ((value = get_sysfs(fs, "args/locktable"))[0])
-	       ? value : sbd.sd_sb.sb_locktable);
+	value = get_sysfs(fs, "args/lockproto");
+	if (value)
+		printf("  Mounted lock proto = \"%s\"\n",
+			value[0] ? value : sbd.sd_sb.sb_lockproto);
+	else
+		printf("  Mounted lock proto = (Not found: %s)\n",
+				strerror(errno));
+
+	value = get_sysfs(fs, "args/locktable");
+	if (value)
+		printf("  Mounted lock table = \"%s\"\n",
+			value[0] ? value : sbd.sd_sb.sb_locktable);
+	else
+		printf("  Mounted lock table = (Not found: %s)\n",
+				strerror(errno));
+
 	printf("  Mounted host data = \"%s\"\n",
 	       get_sysfs(fs, "args/hostdata"));
 	printf("  Journal number = %s\n", get_sysfs(fs, "lockstruct/jid"));
-	flags = get_sysfs_uint(fs, "lockstruct/flags");
-	printf("  Lock module flags = %x", flags);
-	printf("\n");
-	printf("  Local flocks = %s\n",
-	       (get_sysfs_uint(fs, "args/localflocks")) ? "TRUE" : "FALSE");
-	printf("  Local caching = %s\n",
-		(get_sysfs_uint(fs, "args/localcaching")) ? "TRUE" : "FALSE");
+
+	if (get_sysfs_uint(fs, "lockstruct/flags", &flags))
+		printf("  Lock module flags = (Not found: %s)\n", strerror(errno));
+	else
+		printf("  Lock module flags = %x\n", flags);
+
+	if (get_sysfs_uint(fs, "args/localflocks", &flags))
+		printf("  Lock flocks = (Not found: %s)\n", strerror(errno));
+	else
+		printf("  Local flocks = %s\n", flags ? "TRUE" : "FALSE");
+
+	if (get_sysfs_uint(fs, "args/localcaching", &flags))
+		printf("  Lock caching = (Not found: %s)\n", strerror(errno));
+	else
+		printf("  Local caching = %s\n", flags ? "TRUE" : "FALSE");
 
 	/* Read the master statfs file */
 	if (mount_gfs2_meta(&sbd)) {
diff --git a/gfs2/tool/tune.c b/gfs2/tool/tune.c
index b4b24d8..29c529b 100644
--- a/gfs2/tool/tune.c
+++ b/gfs2/tool/tune.c
@@ -39,6 +39,7 @@ get_tune(int argc, char **argv)
 	double ratio;
 	unsigned int num, den;
 	struct gfs2_sbd sbd;
+	char *value;
 
 	if (optind == argc)
 		die("Usage: gfs2_tool gettune <mountpoint>\n");
@@ -65,8 +66,13 @@ get_tune(int argc, char **argv)
 			continue;
 		snprintf(path, PATH_MAX - 1, "tune/%s", de->d_name);
 		if (strcmp(de->d_name, "quota_scale") == 0) {
-			sscanf(get_sysfs(fs, "tune/quota_scale"), "%u %u",
-			       &num, &den);
+			value = get_sysfs(fs, "tune/quota_scale");
+			if (!value) {
+				printf("quota_scale = (Not found: %s)\n",
+						strerror(errno));
+				continue;
+			}
+			sscanf(value, "%u %u", &num, &den);
 			ratio = (double)num / den;
 			printf("quota_scale = %.4f   (%u, %u)\n", ratio, num,
 			       den);