mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git
synced 2026-11-10 19:39:54 +01:00
Jiri Olsa
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 <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Jiri Olsa <[email protected]> Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
61 lines
1.1 KiB
C
61 lines
1.1 KiB
C
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#include "util.h"
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#include "sysfs.h"
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static const char * const sysfs_known_mountpoints[] = {
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"/sys",
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0,
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};
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static int sysfs_found;
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char sysfs_mountpoint[PATH_MAX];
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static int sysfs_valid_mountpoint(const char *sysfs)
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{
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struct statfs st_fs;
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if (statfs(sysfs, &st_fs) < 0)
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return -ENOENT;
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else if (st_fs.f_type != (long) SYSFS_MAGIC)
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return -ENOENT;
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return 0;
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}
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const char *sysfs_find_mountpoint(void)
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{
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const char * const *ptr;
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char type[100];
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FILE *fp;
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if (sysfs_found)
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return (const char *) sysfs_mountpoint;
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ptr = sysfs_known_mountpoints;
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while (*ptr) {
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if (sysfs_valid_mountpoint(*ptr) == 0) {
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sysfs_found = 1;
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strcpy(sysfs_mountpoint, *ptr);
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return sysfs_mountpoint;
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}
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ptr++;
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}
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/* give up and parse /proc/mounts */
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fp = fopen("/proc/mounts", "r");
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if (fp == NULL)
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return NULL;
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while (!sysfs_found &&
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fscanf(fp, "%*s %" STR(PATH_MAX) "s %99s %*s %*d %*d\n",
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sysfs_mountpoint, type) == 2) {
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if (strcmp(type, "sysfs") == 0)
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sysfs_found = 1;
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}
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fclose(fp);
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return sysfs_found ? sysfs_mountpoint : NULL;
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}
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