diff options
Diffstat (limited to 'libsysfs/sysfs_utils.c')
| -rw-r--r-- | libsysfs/sysfs_utils.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/libsysfs/sysfs_utils.c b/libsysfs/sysfs_utils.c new file mode 100644 index 0000000000..a2410abe69 --- /dev/null +++ b/libsysfs/sysfs_utils.c @@ -0,0 +1,156 @@ +/* + * syfs_utils.c + * + * System utility functions for libsysfs + * + * Copyright (C) 2003 International Business Machines, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ +#include "libsysfs.h" +#include "sysfs.h" + +/** + * sysfs_get_mnt_path: Gets the mount point for specified filesystem. + * @fs_type: filesystem type to retrieve mount point + * @mnt_path: place to put the retrieved mount path + * @len: size of mnt_path + * returns 0 with success and -1 with error. + */ +static int sysfs_get_fs_mnt_path(const char *fs_type, char *mnt_path, + size_t len) +{ + FILE *mnt; + struct mntent *mntent; + int ret = 0; + size_t dirlen = 0; + + /* check arg */ + if (fs_type == NULL || mnt_path == NULL) { + errno = EINVAL; + return -1; + } + + if ((mnt = setmntent(SYSFS_PROC_MNTS, "r")) == NULL) { + dprintf(stderr, "Error getting mount information\n"); + return -1; + } + while (ret == 0 && dirlen == 0 && (mntent = getmntent(mnt)) != NULL) { + if (strcmp(mntent->mnt_type, fs_type) == 0) { + dirlen = strlen(mntent->mnt_dir); + if (dirlen <= (len - 1)) { + strcpy(mnt_path, mntent->mnt_dir); + } else { + dprintf(stderr, + "Error - mount path too long\n"); + ret = -1; + } + } + } + endmntent(mnt); + if (dirlen == 0 && ret == 0) { + dprintf(stderr, "Filesystem %s not found!\n", fs_type); + errno = EINVAL; + ret = -1; + } + return ret; +} + +/* + * sysfs_get_mnt_path: Gets the sysfs mount point. + * @mnt_path: place to put "sysfs" mount point + * @len: size of mnt_path + * returns 0 with success and -1 with error. + */ +int sysfs_get_mnt_path(char *mnt_path, size_t len) +{ + int ret = -1; + + if (mnt_path != NULL) + ret = sysfs_get_fs_mnt_path(SYSFS_FSTYPE_NAME, mnt_path, len); + else + errno = EINVAL; + + return ret; +} + +/** + * sysfs_get_name_from_path: returns last name from a "/" delimited path + * @path: path to get name from + * @name: where to put name + * @len: size of name + */ +int sysfs_get_name_from_path(const char *path, char *name, size_t len) +{ + char *n = NULL; + + if (path == NULL || name == NULL) { + errno = EINVAL; + return -1; + } + n = strrchr(path, '/'); + if (n == NULL) { + errno = EINVAL; + return -1; + } + n++; + strncpy(name, n, len); + + return 0; +} + +/** + * sysfs_get_link: returns link source + * @path: symbolic link's path + * @target: where to put name + * @len: size of name + */ +int sysfs_get_link(const char *path, char *target, size_t len) +{ + char devdir[SYSFS_PATH_MAX]; + char linkpath[SYSFS_PATH_MAX]; + char *d = NULL; + + if (path == NULL || target == NULL) { + errno = EINVAL; + return -1; + } + + memset(devdir, 0, SYSFS_PATH_MAX); + memset(linkpath, 0, SYSFS_PATH_MAX); + + if ((sysfs_get_mnt_path(devdir, SYSFS_PATH_MAX)) != 0) { + dprintf(stderr, "Sysfs not supported on this system\n"); + return -1; + } + + if ((readlink(path, linkpath, SYSFS_PATH_MAX)) < 0) { + return -1; + } + + d = linkpath; + + /* getting rid of leading "../.." */ + while (*d == '/' || *d == '.') + d++; + + d--; + + strcat(devdir, d); + strncpy(target, devdir, len); + + return 0; +} |