[PATCH] bin/*: improve error message on failure of nilfs_open()

[Ryusuke Konishi <konishi.ryusuke@xxxxxxxxxxxxx>]

The error message on failure of nilfs_open() function has two issues
in commands lscp, lssu, mkcp, chcp, rmcp, and dumpseg:

 1) When device name is omitted, a null pointer is passed to a string
    type field of the error message and a broken message is printed as
    below:

      lssu: (null): cannot open NILFS

 2) Description of errno is not shown in the error message.

This fixes these issues.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxxxxxx>
---
 bin/chcp.c    |    3 ++-
 bin/dumpseg.c |    3 ++-
 bin/lscp.c    |    4 ++--
 bin/lssu.c    |    4 ++--
 bin/mkcp.c    |    3 ++-
 bin/rmcp.c    |    3 ++-
 6 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/bin/chcp.c b/bin/chcp.c
index 837cf01..8596a14 100644
--- a/bin/chcp.c
+++ b/bin/chcp.c
@@ -139,7 +139,8 @@ int main(int argc, char *argv[])
 
 	nilfs = nilfs_open(dev, NULL, NILFS_OPEN_RDWR | NILFS_OPEN_GCLK);
 	if (nilfs == NULL) {
-		fprintf(stderr, "%s: %s: cannot open NILFS\n", progname, dev);
+		fprintf(stderr, "%s: cannot open NILFS on %s: %m\n",
+			progname, dev ? : "device");
 		exit(1);
 	}
 
diff --git a/bin/dumpseg.c b/bin/dumpseg.c
index 24a3624..0c138b2 100644
--- a/bin/dumpseg.c
+++ b/bin/dumpseg.c
@@ -218,7 +218,8 @@ int main(int argc, char *argv[])
 
 	nilfs = nilfs_open(dev, NULL, NILFS_OPEN_RAW);
 	if (nilfs == NULL) {
-		fprintf(stderr, "%s: %s: cannot open NILFS\n", progname, dev);
+		fprintf(stderr, "%s: cannot open NILFS on %s: %m\n",
+			progname, dev ? : "device");
 		exit(1);
 	}
 
diff --git a/bin/lscp.c b/bin/lscp.c
index 52447e5..2de81b6 100644
--- a/bin/lscp.c
+++ b/bin/lscp.c
@@ -401,8 +401,8 @@ int main(int argc, char *argv[])
 
 	nilfs = nilfs_open(dev, NULL, NILFS_OPEN_RDONLY);
 	if (nilfs == NULL) {
-		fprintf(stderr, "%s: %s: cannot open NILFS\n",
-			progname, dev);
+		fprintf(stderr, "%s: cannot open NILFS on %s: %m\n",
+			progname, dev ? : "device");
 		exit(EXIT_FAILURE);
 	}
 
diff --git a/bin/lssu.c b/bin/lssu.c
index ebbd926..09ed973 100644
--- a/bin/lssu.c
+++ b/bin/lssu.c
@@ -382,8 +382,8 @@ int main(int argc, char *argv[])
 
 	nilfs = nilfs_open(dev, NULL, open_flags);
 	if (nilfs == NULL) {
-		fprintf(stderr, "%s: %s: cannot open NILFS\n",
-			progname, dev);
+		fprintf(stderr, "%s: cannot open NILFS on %s: %m\n",
+			progname, dev ? : "device");
 		exit(1);
 	}
 
diff --git a/bin/mkcp.c b/bin/mkcp.c
index 57cf0c8..9dd6f0e 100644
--- a/bin/mkcp.c
+++ b/bin/mkcp.c
@@ -123,7 +123,8 @@ int main(int argc, char *argv[])
 
 	nilfs = nilfs_open(dev, NULL, NILFS_OPEN_RDWR | NILFS_OPEN_GCLK);
 	if (nilfs == NULL) {
-		fprintf(stderr, "%s: %s: cannot open NILFS\n", progname, dev);
+		fprintf(stderr, "%s: cannot open NILFS on %s: %m\n",
+			progname, dev ? : "device");
 		exit(1);
 	}
 
diff --git a/bin/rmcp.c b/bin/rmcp.c
index 92d672f..0943fe0 100644
--- a/bin/rmcp.c
+++ b/bin/rmcp.c
@@ -193,7 +193,8 @@ int main(int argc, char *argv[])
 
 	nilfs = nilfs_open(dev, NULL, NILFS_OPEN_RDWR);
 	if (nilfs == NULL) {
-		fprintf(stderr, "%s: %s: cannot open NILFS\n", progname, dev);
+		fprintf(stderr, "%s: cannot open NILFS on %s: %m\n",
+			progname, dev ? : "device");
 		exit(1);
 	}
 
-- 
1.7.9.4

--
To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html