summaryrefslogtreecommitdiff
path: root/polux/application/busybox/util-linux/mdev.c
diff options
context:
space:
mode:
Diffstat (limited to 'polux/application/busybox/util-linux/mdev.c')
-rw-r--r--polux/application/busybox/util-linux/mdev.c396
1 files changed, 396 insertions, 0 deletions
diff --git a/polux/application/busybox/util-linux/mdev.c b/polux/application/busybox/util-linux/mdev.c
new file mode 100644
index 0000000000..0edaf10473
--- /dev/null
+++ b/polux/application/busybox/util-linux/mdev.c
@@ -0,0 +1,396 @@
+/* vi: set sw=4 ts=4: */
+/*
+ *
+ * mdev - Mini udev for busybox
+ *
+ * Copyright 2005 Rob Landley <rob@landley.net>
+ * Copyright 2005 Frank Sorenson <frank@tuxrocks.com>
+ *
+ * Licensed under GPL version 2, see file LICENSE in this tarball for details.
+ */
+
+#include "libbb.h"
+#include "xregex.h"
+
+struct globals {
+ int root_major, root_minor;
+};
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define root_major (G.root_major)
+#define root_minor (G.root_minor)
+
+#define MAX_SYSFS_DEPTH 3 /* prevent infinite loops in /sys symlinks */
+
+/* mknod in /dev based on a path like "/sys/block/hda/hda1" */
+static void make_device(char *path, int delete)
+{
+ const char *device_name;
+ int major, minor, type, len;
+ int mode = 0660;
+ uid_t uid = 0;
+ gid_t gid = 0;
+ char *temp = path + strlen(path);
+ char *command = NULL;
+ char *alias = NULL;
+
+ /* Force the configuration file settings exactly. */
+ umask(0);
+
+ /* Try to read major/minor string. Note that the kernel puts \n after
+ * the data, so we don't need to worry about null terminating the string
+ * because sscanf() will stop at the first nondigit, which \n is. We
+ * also depend on path having writeable space after it.
+ */
+ if (!delete) {
+ strcat(path, "/dev");
+ len = open_read_close(path, temp + 1, 64);
+ *temp++ = 0;
+ if (len < 1) {
+ if (ENABLE_FEATURE_MDEV_EXEC)
+ /* no "dev" file, so just try to run script */
+ *temp = 0;
+ else
+ return;
+ }
+ }
+
+ /* Determine device name, type, major and minor */
+ device_name = bb_basename(path);
+ type = (path[5] == 'c' ? S_IFCHR : S_IFBLK);
+
+ if (ENABLE_FEATURE_MDEV_CONF) {
+ FILE *fp;
+ char *line, *vline;
+ unsigned lineno = 0;
+
+ /* If we have a config file, look up the user settings */
+ fp = fopen_or_warn("/etc/mdev.conf", "r");
+ if (!fp)
+ goto end_parse;
+
+ while ((vline = line = xmalloc_getline(fp)) != NULL) {
+ int field;
+
+ /* A pristine copy for command execution. */
+ char *orig_line;
+ if (ENABLE_FEATURE_MDEV_EXEC)
+ orig_line = xstrdup(line);
+
+ ++lineno;
+
+ /* Three fields: regex, uid:gid, mode */
+ for (field = 0; field < (3 + ENABLE_FEATURE_MDEV_RENAME + ENABLE_FEATURE_MDEV_EXEC); ++field) {
+
+ /* Find a non-empty field */
+ char *val;
+ do {
+ val = strtok(vline, " \t");
+ vline = NULL;
+ } while (val && !*val);
+ if (!val) {
+ if (field)
+ break;
+ else
+ goto next_line;
+ }
+
+ if (field == 0) {
+
+ /* Regex to match this device */
+ regex_t match;
+ regmatch_t off;
+ int result;
+
+ /* Is this it? */
+ xregcomp(&match, val, 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 next_line;
+
+ } else if (field == 1) {
+
+ /* uid:gid device ownership */
+ struct passwd *pass;
+ struct group *grp;
+
+ char *str_uid = val;
+ char *str_gid = strchr(val, ':');
+ if (str_gid)
+ *str_gid = '\0', ++str_gid;
+
+ /* Parse UID */
+ pass = getpwnam(str_uid);
+ if (pass)
+ uid = pass->pw_uid;
+ else
+ uid = strtoul(str_uid, NULL, 10);
+
+ /* parse GID */
+ grp = getgrnam(str_gid);
+ if (grp)
+ gid = grp->gr_gid;
+ else
+ gid = strtoul(str_gid, NULL, 10);
+
+ } else if (field == 2) {
+
+ /* Mode device permissions */
+ mode = strtoul(val, NULL, 8);
+
+ } else if (ENABLE_FEATURE_MDEV_RENAME && field == 3) {
+
+ if (*val != '>')
+ ++field;
+ else
+ alias = xstrdup(val + 1);
+
+ }
+
+ if (ENABLE_FEATURE_MDEV_EXEC && field == 3 + ENABLE_FEATURE_MDEV_RENAME) {
+
+ /* Optional command to run */
+ const char *s = "@$*";
+ const char *s2 = strchr(s, *val);
+
+ if (!s2) {
+ /* Force error */
+ field = 1;
+ break;
+ }
+
+ /* Correlate the position in the "@$*" with the delete
+ * step so that we get the proper behavior.
+ */
+ if ((s2 - s + 1) & (1 << delete))
+ command = xstrdup(orig_line + (val + 1 - line));
+ }
+ }
+
+ /* Did everything parse happily? */
+ if (field <= 2)
+ bb_error_msg_and_die("bad line %u", lineno);
+
+ next_line:
+ free(line);
+ if (ENABLE_FEATURE_MDEV_EXEC)
+ free(orig_line);
+ }
+
+ if (ENABLE_FEATURE_CLEAN_UP)
+ fclose(fp);
+
+ end_parse: /* nothing */ ;
+ }
+
+ if (!delete) {
+ if (sscanf(temp, "%d:%d", &major, &minor) != 2) {
+ if (ENABLE_FEATURE_MDEV_EXEC)
+ goto skip_creation;
+ else
+ return;
+ }
+
+ if (ENABLE_FEATURE_MDEV_RENAME)
+ unlink(device_name);
+
+ if (mknod(device_name, mode | type, makedev(major, minor)) && errno != EEXIST)
+ bb_perror_msg_and_die("mknod %s", device_name);
+
+ if (major == root_major && minor == root_minor)
+ symlink(device_name, "root");
+
+ if (ENABLE_FEATURE_MDEV_CONF) {
+ chown(device_name, uid, gid);
+
+ if (ENABLE_FEATURE_MDEV_RENAME && alias) {
+ char *dest;
+
+ temp = strrchr(alias, '/');
+ if (temp) {
+ if (temp[1] != '\0')
+ /* given a file name, so rename it */
+ *temp = '\0';
+ bb_make_directory(alias, 0755, FILEUTILS_RECUR);
+ dest = concat_path_file(alias, device_name);
+ } else
+ dest = alias;
+
+ rename(device_name, dest); // TODO: xrename?
+ symlink(dest, device_name);
+
+ if (alias != dest)
+ free(alias);
+ free(dest);
+ }
+ }
+ skip_creation: /* nothing */ ;
+ }
+ if (ENABLE_FEATURE_MDEV_EXEC && command) {
+ /* setenv will leak memory, so use putenv */
+ char *s = xasprintf("MDEV=%s", device_name);
+ putenv(s);
+ if (system(command) == -1)
+ bb_perror_msg_and_die("cannot run %s", command);
+ s[4] = '\0';
+ unsetenv(s);
+ free(s);
+ free(command);
+ }
+ if (delete)
+ remove_file(device_name, FILEUTILS_FORCE);
+}
+
+/* File callback for /sys/ traversal */
+static int fileAction(const char *fileName,
+ struct stat *statbuf ATTRIBUTE_UNUSED,
+ void *userData,
+ int depth ATTRIBUTE_UNUSED)
+{
+ size_t len = strlen(fileName) - 4;
+ char *scratch = userData;
+
+ if (strcmp(fileName + len, "/dev"))
+ return FALSE;
+
+ strcpy(scratch, fileName);
+ scratch[len] = 0;
+ make_device(scratch, 0);
+
+ return TRUE;
+}
+
+/* Directory callback for /sys/ traversal */
+static int dirAction(const char *fileName ATTRIBUTE_UNUSED,
+ struct stat *statbuf ATTRIBUTE_UNUSED,
+ void *userData ATTRIBUTE_UNUSED,
+ int depth)
+{
+ return (depth >= MAX_SYSFS_DEPTH ? SKIP : TRUE);
+}
+
+/* For the full gory details, see linux/Documentation/firmware_class/README
+ *
+ * Firmware loading works like this:
+ * - kernel sets FIRMWARE env var
+ * - userspace checks /lib/firmware/$FIRMWARE
+ * - userspace waits for /sys/$DEVPATH/loading to appear
+ * - userspace writes "1" to /sys/$DEVPATH/loading
+ * - userspace copies /lib/firmware/$FIRMWARE into /sys/$DEVPATH/data
+ * - userspace writes "0" (worked) or "-1" (failed) to /sys/$DEVPATH/loading
+ * - kernel loads firmware into device
+ */
+static void load_firmware(const char *const firmware, const char *const sysfs_path)
+{
+ int cnt;
+ int firmware_fd, loading_fd, data_fd;
+
+ /* check for $FIRMWARE from kernel */
+ /* XXX: dont bother: open(NULL) works same as open("no-such-file")
+ * if (!firmware)
+ * return;
+ */
+
+ /* check for /lib/firmware/$FIRMWARE */
+ xchdir("/lib/firmware");
+ firmware_fd = xopen(firmware, O_RDONLY);
+
+ /* in case we goto out ... */
+ data_fd = -1;
+
+ /* check for /sys/$DEVPATH/loading ... give 30 seconds to appear */
+ xchdir(sysfs_path);
+ for (cnt = 0; cnt < 30; ++cnt) {
+ loading_fd = open("loading", O_WRONLY);
+ if (loading_fd == -1)
+ sleep(1);
+ else
+ break;
+ }
+ if (loading_fd == -1)
+ goto out;
+
+ /* tell kernel we're loading by `echo 1 > /sys/$DEVPATH/loading` */
+ if (write(loading_fd, "1", 1) != 1)
+ goto out;
+
+ /* load firmware by `cat /lib/firmware/$FIRMWARE > /sys/$DEVPATH/data */
+ data_fd = open("data", O_WRONLY);
+ if (data_fd == -1)
+ goto out;
+ cnt = bb_copyfd_eof(firmware_fd, data_fd);
+
+ /* tell kernel result by `echo [0|-1] > /sys/$DEVPATH/loading` */
+ if (cnt > 0)
+ write(loading_fd, "0", 1);
+ else
+ write(loading_fd, "-1", 2);
+
+ out:
+ if (ENABLE_FEATURE_CLEAN_UP) {
+ close(firmware_fd);
+ close(loading_fd);
+ close(data_fd);
+ }
+}
+
+int mdev_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int mdev_main(int argc, char **argv)
+{
+ char *action;
+ char *env_path;
+ RESERVE_CONFIG_BUFFER(temp,PATH_MAX);
+
+ xchdir("/dev");
+
+ if (argc == 2 && !strcmp(argv[1],"-s")) {
+
+ /* Scan:
+ * mdev -s
+ */
+
+ struct stat st;
+
+ xstat("/", &st);
+ root_major = major(st.st_dev);
+ root_minor = minor(st.st_dev);
+
+ recursive_action("/sys/block",
+ ACTION_RECURSE | ACTION_FOLLOWLINKS,
+ fileAction, dirAction, temp, 0);
+
+ recursive_action("/sys/class",
+ ACTION_RECURSE | ACTION_FOLLOWLINKS,
+ fileAction, dirAction, temp, 0);
+
+ } else {
+
+ /* Hotplug:
+ * env ACTION=... DEVPATH=... mdev
+ * ACTION can be "add" or "remove"
+ * DEVPATH is like "/block/sda" or "/class/input/mice"
+ */
+
+ action = getenv("ACTION");
+ env_path = getenv("DEVPATH");
+ if (!action || !env_path)
+ bb_show_usage();
+
+ sprintf(temp, "/sys%s", env_path);
+ if (!strcmp(action, "remove"))
+ make_device(temp, 1);
+ else if (!strcmp(action, "add")) {
+ make_device(temp, 0);
+
+ if (ENABLE_FEATURE_MDEV_LOAD_FIRMWARE)
+ load_firmware(getenv("FIRMWARE"), temp);
+ }
+ }
+
+ if (ENABLE_FEATURE_CLEAN_UP)
+ RELEASE_CONFIG_BUFFER(temp);
+
+ return 0;
+}