Nothing to see here. Move along.

Not buying it, eh?

I know I said new features before 1.1, but, well...  (I was weak!)

The config file and hotplug modes aren't implemented yet.  Might take a stab at
those tomorrow.  (I _should_ go back to focusing on the bug triage list.)

5 files changed, 180 insertions, 2 deletions

diff --git a/include/applets.h b/include/applets.h
index 79d18207e..47376c624 100644
--- a/include/applets.h
+++ b/include/applets.h
@@ -414,6 +414,9 @@
 #ifdef CONFIG_MD5SUM
         APPLET(md5sum, md5sum_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER)
 #endif
+#ifdef CONFIG_MDEV
+        APPLET(mdev, mdev_main, _BB_DIR_SBIN, _BB_SUID_NEVER)
+#endif
 #ifdef CONFIG_MESG
         APPLET(mesg, mesg_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER)
 #endif
diff --git a/include/usage.h b/include/usage.h
index e595bd9d9..12c45b45f 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -1841,6 +1841,26 @@
         "busybox: OK\n" \
         "^D\n"
 
+#define mdev_trivial_usage \
+        "[-s]"
+#define mdev_full_usage \
+        "\ts\tScan /sys and populate /dev during system boot\n\n" \
+        "Called with no options (via hotplug) it uses environment variables\n" \
+        "to determine which device to add/remove."
+#ifdef CONFIG_FEATURE_MDEV_CONFIG
+#define mdev_notes_usage \
+        "The mdev config file contains lines that look like:\n" \
+        "  hd[a-z][0-9]* 0:3 660\n\n" \
+        "That's device name (with regex match), uid:gid, and permissions.\n\n" \
+        "Optionally, that can be followed (on the same line) by an asterisk\n" \
+        "and a command line to run after creating the corresponding device(s),\n"\
+        "ala:\n\n" \
+        "  hdc root:cdrom 660  *ln -s hdc cdrom\n\n" \
+        "Config file parsing stops on the first matching line.  If no config\n"\
+        "entry is matched, devices are created with default 0:0 660.  (Make\n"\
+        "the last line match .* to override this.)\n\n"
+#endif
+
 #define mesg_trivial_usage \
         "[y|n]"
 #define mesg_full_usage \
@@ -2822,10 +2842,12 @@
         "\t-a\tStart swapping on all swap devices"
 
 #define switch_root_trivial_usage \
-        "NEW_ROOT NEW_INIT [ARGUMENTS_TO_INIT]"
+        "[-c /dev/console] NEW_ROOT NEW_INIT [ARGUMENTS_TO_INIT]"
 #define switch_root_full_usage \
         "Use from PID 1 under initramfs to free initramfs, chroot to NEW_ROOT,\n" \
-        "and exec NEW_INIT.\n"
+        "and exec NEW_INIT.\n\n" \
+        "Options:\n" \
+        "\t-c\tRedirect console to device on new root"
 
 #define sync_trivial_usage \
         ""
diff --git a/util-linux/Config.in b/util-linux/Config.in
index fe71dac2c..5ab54e038 100644
--- a/util-linux/Config.in
+++ b/util-linux/Config.in
@@ -245,6 +245,36 @@ config CONFIG_LOSETUP
           file or block device, and to query the status of a loop device.  This
           version does not currently support enabling data encryption.
 
+config CONFIG_MDEV
+        bool "mdev"
+        default n
+        help
+          mdev is a mini-udev implementation: call it with -s to populate
+          /dev from /sys, then "echo /sbin/mdev > /sys/kernel/hotplug" to
+          have it handle hotplug events afterwards.  Device names are taken
+          from sysfs.
+
+config CONFIG_FEATURE_MDEV_CONFIG
+        bool "  Support /etc/mdev.conf"
+        default n
+        depends on CONFIG_MDEV
+        help
+          The mdev config file contains lines that look like:
+
+            hd[a-z][0-9]* 0:3 660
+
+          That's device name (with regex match), uid:gid, and permissions.
+
+          Optionally, that can be followed (on the same line) by an asterisk
+          and a command line to run after creating the corresponding device(s),
+          ala:
+
+            hdc root:cdrom 660  *ln -s hdc cdrom
+
+          Config file parsing stops on the first matching line.  If no config
+          entry is matched, devices are created with default 0:0 660.  (Make
+          the last line match .* to override this.)
+
 config CONFIG_MKSWAP
         bool "mkswap"
         default n
diff --git a/util-linux/Makefile.in b/util-linux/Makefile.in
index f6fdba96a..782870cdb 100644
--- a/util-linux/Makefile.in
+++ b/util-linux/Makefile.in
@@ -24,12 +24,14 @@ UTILLINUX-$(CONFIG_HWCLOCK)       +=hwclock.o
 UTILLINUX-$(CONFIG_IPCRM)         +=ipcrm.o
 UTILLINUX-$(CONFIG_IPCS)          +=ipcs.o
 UTILLINUX-$(CONFIG_LOSETUP)       +=losetup.o
+UTILLINUX-$(CONFIG_MDEV)          +=mdev.o
 UTILLINUX-$(CONFIG_MKFS_MINIX)    +=mkfs_minix.o
 UTILLINUX-$(CONFIG_MKSWAP)        +=mkswap.o
 UTILLINUX-$(CONFIG_MORE)          +=more.o
 UTILLINUX-$(CONFIG_MOUNT)         +=mount.o
 UTILLINUX-$(CONFIG_FEATURE_MOUNT_NFS)   +=nfsmount.o
 UTILLINUX-$(CONFIG_PIVOT_ROOT)    +=pivot_root.o
+UTILLINUX-$(CONFIG_SWITCH_ROOT)   +=switch_root.o
 UTILLINUX-$(CONFIG_RDATE)         +=rdate.o
 UTILLINUX-$(CONFIG_READPROFILE)   +=readprofile.o
 UTILLINUX-$(CONFIG_SWAPONOFF)     +=swaponoff.o
diff --git a/util-linux/mdev.c b/util-linux/mdev.c
new file mode 100644
index 000000000..49904d17a
--- /dev/null
+++ b/util-linux/mdev.c
@@ -0,0 +1,121 @@
+/* vi:set ts=4:
+ * 
+ * mdev - Mini udev for busybox
+ * 
+ * Copyright 2005 Rob Landley <rob@landley.net>
+ * Copyright 2005 Frank Sorenson <frank@tuxrocks.com>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#define DEV_PATH        "/dev"
+#define DEV_MODE        0660
+
+#include <busybox.h>
+
+/* mknod in /dev based on a path like "/sys/block/hda/hda1" */
+void make_device(char *path)
+{
+        char *device_name, *s;
+        int major,minor,type,len,fd;
+
+        RESERVE_CONFIG_BUFFER(temp,PATH_MAX);
+
+        /* Try to read major/minor string */
+        
+        snprintf(temp, PATH_MAX, "%s/dev", path);
+        fd = open(temp, O_RDONLY);
+        len = read(fd, temp, PATH_MAX-1);
+        if (len<1) goto end;
+        temp[len] = 0;
+        close(fd);
+        
+        /* Determine device name, type, major and minor */
+        
+        device_name = strrchr(path, '/') + 1;
+        type = strncmp(path+5, "block/" ,6) ? S_IFCHR : S_IFBLK;
+        major = minor = 0;
+        for(s = temp; *s; s++) {
+                if(*s == ':') {
+                        major = minor;
+                        minor = 0;
+                } else {
+                        minor *= 10;
+                        minor += (*s) - '0';
+                }
+        }
+
+/* Open config file here, look up permissions */        
+
+        sprintf(temp, "%s/%s", DEV_PATH, device_name);
+        if(mknod(temp, DEV_MODE | type, makedev(major, minor)) && errno != EEXIST)
+                bb_perror_msg_and_die("mknod %s failed", temp);
+        
+/* Perform shellout here */
+
+end:
+        RELEASE_CONFIG_BUFFER(temp);
+}
+
+/* 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. */
+
+void find_dev(char *path)
+{
+        DIR *dir;
+        int len=strlen(path);
+
+        if(!(dir = opendir(path)))
+                bb_perror_msg_and_die("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, PATH_MAX-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 (argc > 1) {
+                if(argc == 2 && !strcmp(argv[1],"-s")) {
+                        RESERVE_CONFIG_BUFFER(temp,PATH_MAX);
+                        strcpy(temp,"/sys/block");
+                        find_dev(temp);
+                        strcpy(temp,"/sys/class");
+                        find_dev(temp);
+                        if(ENABLE_FEATURE_CLEAN_UP)
+                                RELEASE_CONFIG_BUFFER(temp);
+                        return 0;
+                } else bb_show_usage();
+        } 
+        
+/* hotplug support goes here */
+        
+        return 0;
+}