X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flibudev%2Flibudev-util.c;h=8e6d5b621db4cc654b261994290e0d455c472cc8;hp=cb17c3f48cfec810f9432bdd968a73c3cf328f1e;hb=c8f8394a9309d4390daac70b736b34d0b6734f95;hpb=bb061708d5aa83579f213bdfb67253f7027217c3

diff --git a/src/libudev/libudev-util.c b/src/libudev/libudev-util.c
index cb17c3f48..8e6d5b621 100644
--- a/src/libudev/libudev-util.c
+++ b/src/libudev/libudev-util.c
@@ -19,7 +19,10 @@
 #include <ctype.h>
 #include <fcntl.h>
 #include <time.h>
+#include <pwd.h>
+#include <grp.h>
 #include <sys/stat.h>
+#include <sys/param.h>
 
 #include "libudev.h"
 #include "libudev-private.h"
@@ -27,8 +30,168 @@
 /**
  * SECTION:libudev-util
  * @short_description: utils
+ *
+ * Utilities useful when dealing with devices and device node names.
  */
 
+int util_delete_path(struct udev *udev, const char *path)
+{
+        char p[UTIL_PATH_SIZE];
+        char *pos;
+        int err = 0;
+
+        if (path[0] == '/')
+                while(path[1] == '/')
+                        path++;
+        util_strscpy(p, sizeof(p), path);
+        pos = strrchr(p, '/');
+        if (pos == p || pos == NULL)
+                return 0;
+
+        for (;;) {
+                *pos = '\0';
+                pos = strrchr(p, '/');
+
+                /* don't remove the last one */
+                if ((pos == p) || (pos == NULL))
+                        break;
+
+                err = rmdir(p);
+                if (err < 0) {
+                        if (errno == ENOENT)
+                                err = 0;
+                        break;
+                }
+        }
+        return err;
+}
+
+uid_t util_lookup_user(struct udev *udev, const char *user)
+{
+        char *endptr;
+        struct passwd pwbuf;
+        struct passwd *pw;
+        uid_t uid;
+        size_t buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
+        char *buf = alloca(buflen);
+
+        if (strcmp(user, "root") == 0)
+                return 0;
+        uid = strtoul(user, &endptr, 10);
+        if (endptr[0] == '\0')
+                return uid;
+
+        errno = getpwnam_r(user, &pwbuf, buf, buflen, &pw);
+        if (pw != NULL)
+                return pw->pw_uid;
+        if (errno == 0 || errno == ENOENT || errno == ESRCH)
+                udev_err(udev, "specified user '%s' unknown\n", user);
+        else
+                udev_err(udev, "error resolving user '%s': %m\n", user);
+        return 0;
+}
+
+gid_t util_lookup_group(struct udev *udev, const char *group)
+{
+        char *endptr;
+        struct group grbuf;
+        struct group *gr;
+        gid_t gid = 0;
+        size_t buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
+        char *buf = NULL;
+
+        if (strcmp(group, "root") == 0)
+                return 0;
+        gid = strtoul(group, &endptr, 10);
+        if (endptr[0] == '\0')
+                return gid;
+        gid = 0;
+        for (;;) {
+                char *newbuf;
+
+                newbuf = realloc(buf, buflen);
+                if (!newbuf)
+                        break;
+                buf = newbuf;
+                errno = getgrnam_r(group, &grbuf, buf, buflen, &gr);
+                if (gr != NULL) {
+                        gid = gr->gr_gid;
+                } else if (errno == ERANGE) {
+                        buflen *= 2;
+                        continue;
+                } else if (errno == 0 || errno == ENOENT || errno == ESRCH) {
+                        udev_err(udev, "specified group '%s' unknown\n", group);
+                } else {
+                        udev_err(udev, "error resolving group '%s': %m\n", group);
+                }
+                break;
+        }
+        free(buf);
+        return gid;
+}
+
+/* handle "[<SUBSYSTEM>/<KERNEL>]<attribute>" format */
+int util_resolve_subsys_kernel(struct udev *udev, const char *string,
+                               char *result, size_t maxsize, int read_value)
+{
+        char temp[UTIL_PATH_SIZE];
+        char *subsys;
+        char *sysname;
+        struct udev_device *dev;
+        char *attr;
+
+        if (string[0] != '[')
+                return -1;
+
+        util_strscpy(temp, sizeof(temp), string);
+
+        subsys = &temp[1];
+
+        sysname = strchr(subsys, '/');
+        if (sysname == NULL)
+                return -1;
+        sysname[0] = '\0';
+        sysname = &sysname[1];
+
+        attr = strchr(sysname, ']');
+        if (attr == NULL)
+                return -1;
+        attr[0] = '\0';
+        attr = &attr[1];
+        if (attr[0] == '/')
+                attr = &attr[1];
+        if (attr[0] == '\0')
+                attr = NULL;
+
+        if (read_value && attr == NULL)
+                return -1;
+
+        dev = udev_device_new_from_subsystem_sysname(udev, subsys, sysname);
+        if (dev == NULL)
+                return -1;
+
+        if (read_value) {
+                const char *val;
+
+                val = udev_device_get_sysattr_value(dev, attr);
+                if (val != NULL)
+                        util_strscpy(result, maxsize, val);
+                else
+                        result[0] = '\0';
+                udev_dbg(udev, "value '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result);
+        } else {
+                size_t l;
+                char *s;
+
+                s = result;
+                l = util_strpcpyl(&s, maxsize, udev_device_get_syspath(dev), NULL);
+                if (attr != NULL)
+                        util_strpcpyl(&s, l, "/", attr, NULL);
+                udev_dbg(udev, "path '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result);
+        }
+        udev_device_unref(dev);
+        return 0;
+}
 ssize_t util_get_sys_core_link_value(struct udev *udev, const char *slink, const char *syspath, char *value, size_t size)
 {
         char path[UTIL_PATH_SIZE];
@@ -62,7 +225,7 @@ int util_resolve_sys_link(struct udev *udev, char *syspath, size_t size)
                 return -1;
         link_target[len] = '\0';
 
-        for (back = 0; strncmp(&link_target[back * 3], "../", 3) == 0; back++)
+        for (back = 0; startswith(&link_target[back * 3], "../"); back++)
                 ;
         for (i = 0; i <= back; i++) {
                 base = strrchr(syspath, '/');
@@ -84,11 +247,11 @@ int util_log_priority(const char *priority)
         prio = strtol(priority, &endptr, 10);
         if (endptr[0] == '\0' || isspace(endptr[0]))
                 return prio;
-        if (strncmp(priority, "err", 3) == 0)
+        if (startswith(priority, "err"))
                 return LOG_ERR;
-        if (strncmp(priority, "info", 4) == 0)
+        if (startswith(priority, "info"))
                 return LOG_INFO;
-        if (strncmp(priority, "debug", 5) == 0)
+        if (startswith(priority, "debug"))
                 return LOG_DEBUG;
         return 0;
 }