forked from luck/tmp_suning_uos_patched
e90fda0635
Adding sysfs object to provide sysfs mount information in the same way as debugfs object does. The object provides following function: sysfs_find_mountpoint which returns the sysfs mount mount. Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1327674868-10486-4-git-send-email-jolsa@redhat.com Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
61 lines
1.1 KiB
C
61 lines
1.1 KiB
C
|
|
#include "util.h"
|
|
#include "sysfs.h"
|
|
|
|
static const char * const sysfs_known_mountpoints[] = {
|
|
"/sys",
|
|
0,
|
|
};
|
|
|
|
static int sysfs_found;
|
|
char sysfs_mountpoint[PATH_MAX];
|
|
|
|
static int sysfs_valid_mountpoint(const char *sysfs)
|
|
{
|
|
struct statfs st_fs;
|
|
|
|
if (statfs(sysfs, &st_fs) < 0)
|
|
return -ENOENT;
|
|
else if (st_fs.f_type != (long) SYSFS_MAGIC)
|
|
return -ENOENT;
|
|
|
|
return 0;
|
|
}
|
|
|
|
const char *sysfs_find_mountpoint(void)
|
|
{
|
|
const char * const *ptr;
|
|
char type[100];
|
|
FILE *fp;
|
|
|
|
if (sysfs_found)
|
|
return (const char *) sysfs_mountpoint;
|
|
|
|
ptr = sysfs_known_mountpoints;
|
|
while (*ptr) {
|
|
if (sysfs_valid_mountpoint(*ptr) == 0) {
|
|
sysfs_found = 1;
|
|
strcpy(sysfs_mountpoint, *ptr);
|
|
return sysfs_mountpoint;
|
|
}
|
|
ptr++;
|
|
}
|
|
|
|
/* give up and parse /proc/mounts */
|
|
fp = fopen("/proc/mounts", "r");
|
|
if (fp == NULL)
|
|
return NULL;
|
|
|
|
while (!sysfs_found &&
|
|
fscanf(fp, "%*s %" STR(PATH_MAX) "s %99s %*s %*d %*d\n",
|
|
sysfs_mountpoint, type) == 2) {
|
|
|
|
if (strcmp(type, "sysfs") == 0)
|
|
sysfs_found = 1;
|
|
}
|
|
|
|
fclose(fp);
|
|
|
|
return sysfs_found ? sysfs_mountpoint : NULL;
|
|
}
|