[Ocfs2-tools-devel] [PATCH] adding code to mounted.c to translate /dev/dm-[N] names to /dev/mapper/xxx names.

[xiaowei hu]

it doesn't report errors for it will deal with those dev files as no
need to translate.

codes here :
if (devname)
> > +				snprintf(dev->dev_name, sizeof(dev->dev_name), "%s", devname);
> > +			else
> > +				snprintf(dev->dev_name, sizeof(dev->dev_name), "/dev/%s", name);

let this program run as the original .And users may doesn't want to know what happened.



 
On Fri, 2009-12-04 at 10:29 +0800, Tristan wrote:
> Btw, you're required to handle errors gracefully I guess:-)
> 
> such as,
> 
> dir = opendir(dirname);
> 
> if (!dir) {
> ret = errno;
> com_err(programe, 0, "Can not open dir %s: %s\n", dirname, strerror(ret));
> return -1;
> }
> 
> Tristan
> 
> XiaoweiHu wrote:
> > Signed-off-by: XiaoweiHu <xiaowei.hu at oracle.com>
> > ---
> >  mounted.ocfs2/mounted.c |   76 +++++++++++++++++++++++++++++++++++++++++++++-
> >  1 files changed, 74 insertions(+), 2 deletions(-)
> >
> > diff --git a/mounted.ocfs2/mounted.c b/mounted.ocfs2/mounted.c
> > index e4c5877..c691a3d 100644
> > --- a/mounted.ocfs2/mounted.c
> > +++ b/mounted.ocfs2/mounted.c
> > @@ -33,6 +33,7 @@
> >  #include <linux/fd.h>
> >  #include <string.h>
> >  #include <sys/stat.h>
> > +#include <dirent.h>
> >  
> >  #include <uuid/uuid.h>
> >  
> > @@ -155,12 +156,70 @@ static void ocfs2_print_quick_detect(struct list_head *dev_list)
> >  	}
> >  }
> >  
> > +char *devname_strndup(const char *s, int length)
> > +{
> > +        char *ret;
> > +
> > +        if (!s)
> > +                return NULL;
> > +
> > +        if (!length)
> > +                length = strlen(s);
> > +
> > +        ret = malloc(length + 1);
> > +        if (ret) {
> > +                strncpy(ret, s, length);
> > +                ret[length] = '\0';
> > +        }
> > +        return ret;
> > +}
> > +
> > +char *devname_strdup(const char *s)
> > +{
> > +        return devname_strndup(s, 0);
> > +}
> > +
> > +void scan_dir_for_dev(char *dirname, dev_t devno, char **devname)
> > +{
> > +        DIR     *dir;
> > +        struct dirent *dp;
> > +        char    path[1024];
> > +        int     dirlen;
> > +        struct stat st;
> > +
> > +        if ((dir = opendir(dirname)) == NULL)
> > +                return;
> > +        dirlen = strlen(dirname) + 2;
> > +        while ((dp = readdir(dir)) != 0) {
> > +                if (dirlen + strlen(dp->d_name) >= sizeof(path))
> > +                        continue;
> > +
> > +                if (dp->d_name[0] == '.' &&
> > +                    ((dp->d_name[1] == 0) ||
> > +                     ((dp->d_name[1] == '.') && (dp->d_name[2] == 0))))
> > +                        continue;
> > +
> > +                sprintf(path, "%s/%s", dirname, dp->d_name);
> > +                if (stat(path, &st) < 0)
> > +                        continue;
> > +
> > +                if (S_ISBLK(st.st_mode) && st.st_rdev == devno) {
> > +			*devname = devname_strdup(path);
> > +                        break;
> > +                }
> > +        }
> > +        closedir(dir);
> > +        return;
> > +}
> > +
> >  static errcode_t ocfs2_partition_list (struct list_head *dev_list)
> >  {
> >  	errcode_t ret = 0;
> >  	FILE *proc;
> >  	char line[256];
> >  	char name[256];
> > +	char *devname = NULL;
> > +	int major,minor;
> >  	ocfs2_devices *dev;
> >  
> >  	proc = fopen ("/proc/partitions", "r");
> > @@ -170,14 +229,27 @@ static errcode_t ocfs2_partition_list (struct list_head *dev_list)
> >  	}
> >  
> >  	while (fgets (line, sizeof(line), proc) != NULL) {
> > -		if (sscanf(line, "%*d %*d %*d %99[^ \t\n]", name) != 1)
> > +		if (sscanf(line, "%d %d %*d %99[^ \t\n]", &major, &minor, name) != 3)
> >  			continue;
> >  
> >  		ret = ocfs2_malloc0(sizeof(ocfs2_devices), &dev);
> >  		if (ret)
> >  			goto bail;
> >  
> > -		snprintf(dev->dev_name, sizeof(dev->dev_name), "/dev/%s", name);
> > +		/* Try to translate private device-mapper dm-<N> names
> > +         	 * to standard /dev/mapper/<name>.
> > +         	 */
> > +        	if (!strncmp(name, "dm-", 3) && isdigit(name[3])) {
> > +                        scan_dir_for_dev("/dev/mapper", makedev(major, minor), &devname);
> > +                	if (devname)
> > +				snprintf(dev->dev_name, sizeof(dev->dev_name), "%s", devname);
> > +			else
> > +				snprintf(dev->dev_name, sizeof(dev->dev_name), "/dev/%s", name);
> > +
> > +        	} else {
> > +			snprintf(dev->dev_name, sizeof(dev->dev_name), "/dev/%s", name);
> > +		}
> > +
> >  		list_add_tail(&(dev->list), dev_list);
> >  	}
> >  
> >   
>