1 2 #include "util.h" 3 #include "sysfs.h" 4 5 static const char * const sysfs_known_mountpoints[] = { 6 "/sys", 7 0, 8 }; 9 10 static int sysfs_found; 11 char sysfs_mountpoint[PATH_MAX + 1]; 12 13 static int sysfs_valid_mountpoint(const char *sysfs) 14 { 15 #ifndef __APPLE__ 16 struct statfs st_fs; 17 18 if (statfs(sysfs, &st_fs) < 0) 19 return -ENOENT; 20 else if (st_fs.f_type != (long) SYSFS_MAGIC) 21 return -ENOENT; 22 #endif 23 24 return 0; 25 } 26 27 const char *sysfs_find_mountpoint(void) 28 { 29 const char * const *ptr; 30 char type[100]; 31 FILE *fp; 32 33 if (sysfs_found) 34 return (const char *) sysfs_mountpoint; 35 36 ptr = sysfs_known_mountpoints; 37 while (*ptr) { 38 if (sysfs_valid_mountpoint(*ptr) == 0) { 39 sysfs_found = 1; 40 strcpy(sysfs_mountpoint, *ptr); 41 return sysfs_mountpoint; 42 } 43 ptr++; 44 } 45 46 /* give up and parse /proc/mounts */ 47 fp = fopen("/proc/mounts", "r"); 48 if (fp == NULL) 49 return NULL; 50 51 while (!sysfs_found && 52 fscanf(fp, "%*s %" STR(PATH_MAX) "s %99s %*s %*d %*d\n", 53 sysfs_mountpoint, type) == 2) { 54 55 if (strcmp(type, "sysfs") == 0) 56 sysfs_found = 1; 57 } 58 59 fclose(fp); 60 61 return sysfs_found ? sysfs_mountpoint : NULL; 62 } 63
