--- /dev/null
+/* vi:set ts=4:
+ *
+ * mdev - Mini udev for busybox
+ *
+ * Copyright 2005 Rob Landley <rob@landley.net>
+ * Copyright 2005 Frank Sorenson <frank@tuxrocks.com>
+ */
+
+#include "toys.h"
+#include "lib/xregcomp.h"
+
+// mknod in /dev based on a path like "/sys/block/hda/hda1"
+static void make_device(char *path)
+{
+ char *device_name, *s, *temp;
+ int major, minor, type, len, fd;
+ int mode = 0660;
+ uid_t uid = 0;
+ gid_t gid = 0;
+
+ // Try to read major/minor string
+
+ temp = path+strlen(path);
+ strcpy(temp, "/dev");
+ fd = open(path, O_RDONLY);
+ *temp=0;
+ temp++;
+ len = read(fd, temp, 64);
+ close(fd);
+ if (len<1) return;
+ temp[len] = 0;
+
+ // Determine device name, type, major and minor
+
+ device_name = strrchr(path, '/') + 1;
+ type = path[5]=='c' ? S_IFCHR : S_IFBLK;
+ major = minor = 0;
+ sscanf(temp, "%u:%u", &major, &minor);
+
+ // If we have a config file, look up permissions for this device
+
+ if (CFG_MDEV_CONF) {
+ char *conf, *pos, *end;
+
+ // mmap the config file
+ if (-1!=(fd = open("/etc/mdev.conf", O_RDONLY))) {
+ len = lseek(fd, 0, SEEK_END);
+ conf = mmap(NULL, len, PROT_READ, MAP_PRIVATE, fd, 0);
+ if (conf) {
+ int line = 0;
+
+ // Loop through lines in mmaped file
+ for (pos = conf; pos-conf<len;) {
+ int field;
+ char *end2;
+
+ line++;
+ // find end of this line
+ for(end = pos; end-conf<len && *end!='\n'; end++);
+
+ // Three fields: regex, uid:gid, mode
+ for (field = 3; field; field--) {
+ // Skip whitespace
+ while (pos<end && isspace(*pos)) pos++;
+ if (pos==end || *pos=='#') break;
+ for (end2 = pos;
+ end2<end && !isspace(*end2) && *end2!='#'; end2++);
+ switch(field) {
+ // Regex to match this device
+ case 3:
+ {
+ char *regex = strndupa(pos, end2-pos);
+ regex_t match;
+ regmatch_t off;
+ int result;
+
+ // Is this it?
+ xregcomp(&match, regex, REG_EXTENDED);
+ result=regexec(&match, device_name, 1, &off, 0);
+ regfree(&match);
+
+ // If not this device, skip rest of line
+ if (result || off.rm_so
+ || off.rm_eo!=strlen(device_name))
+ goto end_line;
+
+ break;
+ }
+ // uid:gid
+ case 2:
+ {
+ char *s2;
+
+ // Find :
+ for(s = pos; s<end2 && *s!=':'; s++);
+ if (s==end2) goto end_line;
+
+ // Parse UID
+ uid = strtoul(pos,&s2,10);
+ if (s!=s2) {
+ struct passwd *pass;
+ pass = getpwnam(strndupa(pos, s-pos));
+ if (!pass) goto end_line;
+ uid = pass->pw_uid;
+ }
+ s++;
+ // parse GID
+ gid = strtoul(s,&s2,10);
+ if (end2!=s2) {
+ struct group *grp;
+ grp = getgrnam(strndupa(s, end2-s));
+ if (!grp) goto end_line;
+ gid = grp->gr_gid;
+ }
+ break;
+ }
+ // mode
+ case 1:
+ {
+ mode = strtoul(pos, &pos, 8);
+ if (pos!=end2) goto end_line;
+ goto found_device;
+ }
+ }
+ pos=end2;
+ }
+end_line:
+ // Did everything parse happily?
+ if (field && field!=3) error_exit("Bad line %d", line);
+
+ // Next line
+ pos = ++end;
+ }
+found_device:
+ munmap(conf, len);
+ }
+ close(fd);
+ }
+ }
+
+ sprintf(temp, "/dev/%s", device_name);
+ umask(0);
+ if (mknod(temp, mode | type, makedev(major, minor)) && errno != EEXIST)
+ perror_exit("mknod %s failed", temp);
+
+ if (CFG_MDEV_CONF) chown(temp, uid, gid);
+}
+
+// Recursive search of /sys/block or /sys/class. path must be a writeable
+// buffer of size PATH_MAX containing the directory string to start at.
+
+static void find_dev(char *path)
+{
+ DIR *dir;
+ int len=strlen(path);
+
+ if (!(dir = opendir(path)))
+ perror_exit("No %s",path);
+
+ for (;;) {
+ struct dirent *entry = readdir(dir);
+
+ if (!entry) break;
+
+ // Skip "." and ".." (also skips hidden files, which is ok)
+
+ if (entry->d_name[0]=='.') continue;
+
+ if (entry->d_type == DT_DIR) {
+ snprintf(path+len, sizeof(toybuf)-len, "/%s", entry->d_name);
+ find_dev(path);
+ path[len] = 0;
+ }
+
+ // If there's a dev entry, mknod it
+
+ if (strcmp(entry->d_name, "dev")) make_device(path);
+ }
+
+ closedir(dir);
+}
+
+int mdev_main(int argc, char *argv[])
+{
+ if (toys.optflags) {
+ strcpy(toybuf, "/sys/block");
+ find_dev(toybuf);
+ strcpy(toybuf, "/sys/class");
+ find_dev(toybuf);
+ return 0;
+ }
+
+ // hotplug support goes here
+
+ return 0;
+}
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