#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;}