1 /* vi: set sw=4 ts=4: */
3 * mdev - Mini udev for busybox
5 * Copyright 2005 Rob Landley <rob@landley.net>
6 * Copyright 2005 Frank Sorenson <frank@tuxrocks.com>
8 * Licensed under GPLv2, see file LICENSE in this source tree.
14 //config: select PLATFORM_LINUX
16 //config: mdev is a mini-udev implementation for dynamically creating device
17 //config: nodes in the /dev directory.
19 //config: For more information, please see docs/mdev.txt
21 //config:config FEATURE_MDEV_CONF
22 //config: bool "Support /etc/mdev.conf"
24 //config: depends on MDEV
26 //config: Add support for the mdev config file to control ownership and
27 //config: permissions of the device nodes.
29 //config: For more information, please see docs/mdev.txt
31 //config:config FEATURE_MDEV_RENAME
32 //config: bool "Support subdirs/symlinks"
34 //config: depends on FEATURE_MDEV_CONF
36 //config: Add support for renaming devices and creating symlinks.
38 //config: For more information, please see docs/mdev.txt
40 //config:config FEATURE_MDEV_RENAME_REGEXP
41 //config: bool "Support regular expressions substitutions when renaming device"
43 //config: depends on FEATURE_MDEV_RENAME
45 //config: Add support for regular expressions substitutions when renaming
48 //config:config FEATURE_MDEV_EXEC
49 //config: bool "Support command execution at device addition/removal"
51 //config: depends on FEATURE_MDEV_CONF
53 //config: This adds support for an optional field to /etc/mdev.conf for
54 //config: executing commands when devices are created/removed.
56 //config: For more information, please see docs/mdev.txt
58 //config:config FEATURE_MDEV_LOAD_FIRMWARE
59 //config: bool "Support loading of firmwares"
61 //config: depends on MDEV
63 //config: Some devices need to load firmware before they can be usable.
65 //config: These devices will request userspace look up the files in
66 //config: /lib/firmware/ and if it exists, send it to the kernel for
67 //config: loading into the hardware.
69 //applet:IF_MDEV(APPLET(mdev, BB_DIR_SBIN, BB_SUID_DROP))
71 //kbuild:lib-$(CONFIG_MDEV) += mdev.o
73 //usage:#define mdev_trivial_usage
75 //usage:#define mdev_full_usage "\n\n"
76 //usage: "mdev -s is to be run during boot to scan /sys and populate /dev.\n"
78 //usage: "Bare mdev is a kernel hotplug helper. To activate it:\n"
79 //usage: " echo /sbin/mdev >/proc/sys/kernel/hotplug\n"
80 //usage: IF_FEATURE_MDEV_CONF(
82 //usage: "It uses /etc/mdev.conf with lines\n"
83 //usage: " [-]DEVNAME UID:GID PERM"
84 //usage: IF_FEATURE_MDEV_RENAME(" [>|=PATH]|[!]")
85 //usage: IF_FEATURE_MDEV_EXEC(" [@|$|*PROG]")
87 //usage: "where DEVNAME is device name regex, @major,minor[-minor2], or\n"
88 //usage: "environment variable regex. A common use of the latter is\n"
89 //usage: "to load modules for hotplugged devices:\n"
90 //usage: " $MODALIAS=.* 0:0 660 @modprobe \"$MODALIAS\"\n"
93 //usage: "If /dev/mdev.seq file exists, mdev will wait for its value\n"
94 //usage: "to match $SEQNUM variable. This prevents plug/unplug races.\n"
95 //usage: "To activate this feature, create empty /dev/mdev.seq at boot."
97 //usage:#define mdev_notes_usage ""
98 //usage: IF_FEATURE_MDEV_CONFIG(
99 //usage: "The mdev config file contains lines that look like:\n"
100 //usage: " hd[a-z][0-9]* 0:3 660\n\n"
101 //usage: "That's device name (with regex match), uid:gid, and permissions.\n\n"
102 //usage: IF_FEATURE_MDEV_EXEC(
103 //usage: "Optionally, that can be followed (on the same line) by a special character\n"
104 //usage: "and a command line to run after creating/before deleting the corresponding\n"
105 //usage: "device(s). The environment variable $MDEV indicates the active device node\n"
106 //usage: "(which is useful if it's a regex match). For example:\n\n"
107 //usage: " hdc root:cdrom 660 *ln -s $MDEV cdrom\n\n"
108 //usage: "The special characters are @ (run after creating), $ (run before deleting),\n"
109 //usage: "and * (run both after creating and before deleting). The commands run in\n"
110 //usage: "the /dev directory, and use system() which calls /bin/sh.\n\n"
112 //usage: "Config file parsing stops on the first matching line. If no config\n"
113 //usage: "entry is matched, devices are created with default 0:0 660. (Make\n"
114 //usage: "the last line match .* to override this.)\n\n"
120 /* "mdev -s" scans /sys/class/xxx, looking for directories which have dev
121 * file (it is of the form "M:m\n"). Example: /sys/class/tty/tty0/dev
122 * contains "4:0\n". Directory name is taken as device name, path component
123 * directly after /sys/class/ as subsystem. In this example, "tty0" and "tty".
124 * Then mdev creates the /dev/device_name node.
125 * If /sys/class/.../dev file does not exist, mdev still may act
126 * on this device: see "@|$|*command args..." parameter in config file.
128 * mdev w/o parameters is called as hotplug helper. It takes device
129 * and subsystem names from $DEVPATH and $SUBSYSTEM, extracts
130 * maj,min from "/sys/$DEVPATH/dev" and also examines
131 * $ACTION ("add"/"delete") and $FIRMWARE.
133 * If action is "add", mdev creates /dev/device_name similarly to mdev -s.
134 * (todo: explain "delete" and $FIRMWARE)
136 * If /etc/mdev.conf exists, it may modify /dev/device_name's properties.
137 * /etc/mdev.conf file format:
139 * [-][subsystem/]device user:grp mode [>|=path]|[!] [@|$|*command args...]
140 * [-]@maj,min[-min2] user:grp mode [>|=path]|[!] [@|$|*command args...]
141 * [-]$envvar=val user:grp mode [>|=path]|[!] [@|$|*command args...]
143 * Leading minus in 1st field means "don't stop on this line", otherwise
144 * search is stopped after the matching line is encountered.
146 * The device name or "subsystem/device" combo is matched against 1st field
147 * (which is a regex), or maj,min is matched against 1st field,
148 * or specified environment variable (as regex) is matched against 1st field.
150 * $envvar=val format is useful for loading modules for hot-plugged devices
151 * which do not have driver loaded yet. In this case /sys/class/.../dev
152 * does not exist, but $MODALIAS is set to needed module's name
153 * (actually, an alias to it) by kernel. This rule instructs mdev
154 * to load the module and exit:
155 * $MODALIAS=.* 0:0 660 @modprobe "$MODALIAS"
156 * The kernel will generate another hotplug event when /sys/class/.../dev
159 * When line matches, the device node is created, chmod'ed and chown'ed,
160 * moved to path, and if >path, a symlink to moved node is created,
161 * all this if /sys/class/.../dev exists.
163 * =loop/ - moves to /dev/loop
164 * >disk/sda%1 - moves to /dev/disk/sdaN, makes /dev/sdaN a symlink
166 * Then "command args..." is executed (via sh -c 'command args...').
167 * @:execute on creation, $:on deletion, *:on both.
168 * This happens regardless of /sys/class/.../dev existence.
174 bool regex_has_slash;
177 struct bb_uidgid_t ugid;
180 IF_FEATURE_MDEV_EXEC(char *r_cmd;)
185 int root_major, root_minor;
187 #if ENABLE_FEATURE_MDEV_CONF
188 const char *filename;
190 struct rule **rule_vec;
193 struct rule cur_rule;
195 #define G (*(struct globals*)&bb_common_bufsiz1)
196 #define INIT_G() do { } while (0)
199 /* Prevent infinite loops in /sys symlinks */
200 #define MAX_SYSFS_DEPTH 3
202 /* We use additional 64+ bytes in make_device() */
203 #define SCRATCH_SIZE 80
206 # define dbg(...) bb_error_msg(__VA_ARGS__)
208 # define dbg(...) ((void)0)
212 #if ENABLE_FEATURE_MDEV_CONF
214 static void make_default_cur_rule(void)
216 memset(&G.cur_rule, 0, sizeof(G.cur_rule));
217 G.cur_rule.maj = -1; /* "not a @major,minor rule" */
218 G.cur_rule.mode = 0660;
221 static void clean_up_cur_rule(void)
223 free(G.cur_rule.envvar);
224 if (G.cur_rule.regex_compiled)
225 regfree(&G.cur_rule.match);
226 free(G.cur_rule.ren_mov);
227 IF_FEATURE_MDEV_EXEC(free(G.cur_rule.r_cmd);)
228 make_default_cur_rule();
231 static void parse_next_rule(void)
233 /* Note: on entry, G.cur_rule is set to default */
238 if (!config_read(G.parser, tokens, 4, 3, "# \t", PARSE_NORMAL))
241 /* Fields: [-]regex uid:gid mode [alias] [cmd] */
242 dbg("token1:'%s'", tokens[1]);
246 G.cur_rule.keep_matching = ('-' == val[0]);
247 val += G.cur_rule.keep_matching; /* swallow leading dash */
249 /* @major,minor[-minor2] */
250 /* (useful when name is ambiguous:
251 * "/sys/class/usb/lp0" and
252 * "/sys/class/printer/lp0")
254 int sc = sscanf(val, "@%u,%u-%u", &G.cur_rule.maj, &G.cur_rule.min0, &G.cur_rule.min1);
255 if (sc < 2 || G.cur_rule.maj < 0) {
256 bb_error_msg("bad @maj,min on line %d", G.parser->lineno);
260 G.cur_rule.min1 = G.cur_rule.min0;
263 char *eq = strchr(++val, '=');
265 bb_error_msg("bad $envvar=regex on line %d", G.parser->lineno);
268 G.cur_rule.envvar = xstrndup(val, eq - val);
271 xregcomp(&G.cur_rule.match, val, REG_EXTENDED);
272 G.cur_rule.regex_compiled = 1;
273 G.cur_rule.regex_has_slash = (strchr(val, '/') != NULL);
276 /* 2nd field: uid:gid - device ownership */
277 if (get_uidgid(&G.cur_rule.ugid, tokens[1], /*allow_numeric:*/ 1) == 0) {
278 bb_error_msg("unknown user/group '%s' on line %d", tokens[1], G.parser->lineno);
282 /* 3rd field: mode - device permissions */
283 bb_parse_mode(tokens[2], &G.cur_rule.mode);
285 /* 4th field (opt): ">|=alias" or "!" to not create the node */
287 if (ENABLE_FEATURE_MDEV_RENAME && val && strchr(">=!", val[0])) {
288 char *s = skip_non_whitespace(val);
289 G.cur_rule.ren_mov = xstrndup(val, s - val);
290 val = skip_whitespace(s);
293 if (ENABLE_FEATURE_MDEV_EXEC && val && val[0]) {
294 const char *s = "$@*";
295 const char *s2 = strchr(s, val[0]);
297 bb_error_msg("bad line %u", G.parser->lineno);
300 IF_FEATURE_MDEV_EXEC(G.cur_rule.r_cmd = xstrdup(val);)
306 } /* while (config_read) */
308 dbg("config_close(G.parser)");
309 config_close(G.parser);
315 /* If mdev -s, we remember rules in G.rule_vec[].
316 * Otherwise, there is no point in doing it, and we just
317 * save only one parsed rule in G.cur_rule.
319 static const struct rule *next_rule(void)
323 /* Open conf file if we didn't do it yet */
324 if (!G.parser && G.filename) {
325 dbg("config_open('%s')", G.filename);
326 G.parser = config_open2(G.filename, fopen_for_read);
332 /* Do we have rule parsed already? */
333 if (G.rule_vec[G.rule_idx]) {
334 dbg("< G.rule_vec[G.rule_idx:%d]=%p", G.rule_idx, G.rule_vec[G.rule_idx]);
335 return G.rule_vec[G.rule_idx++];
337 make_default_cur_rule();
343 /* Parse one more rule if file isn't fully read */
347 if (G.rule_vec) { /* mdev -s */
348 rule = memcpy(xmalloc(sizeof(G.cur_rule)), &G.cur_rule, sizeof(G.cur_rule));
349 G.rule_vec = xrealloc_vector(G.rule_vec, 4, G.rule_idx);
350 G.rule_vec[G.rule_idx++] = rule;
351 dbg("> G.rule_vec[G.rule_idx:%d]=%p", G.rule_idx, G.rule_vec[G.rule_idx]);
360 # define next_rule() (&G.cur_rule)
364 /* Builds an alias path.
365 * This function potentionally reallocates the alias parameter.
366 * Only used for ENABLE_FEATURE_MDEV_RENAME
368 static char *build_alias(char *alias, const char *device_name)
372 /* ">bar/": rename to bar/device_name */
373 /* ">bar[/]baz": rename to bar[/]baz */
374 dest = strrchr(alias, '/');
375 if (dest) { /* ">bar/[baz]" ? */
376 *dest = '\0'; /* mkdir bar */
377 bb_make_directory(alias, 0755, FILEUTILS_RECUR);
379 if (dest[1] == '\0') { /* ">bar/" => ">bar/device_name" */
381 alias = concat_path_file(alias, device_name);
389 /* mknod in /dev based on a path like "/sys/block/hda/hda1"
390 * NB1: path parameter needs to have SCRATCH_SIZE scratch bytes
391 * after NUL, but we promise to not mangle (IOW: to restore if needed)
393 * NB2: "mdev -s" may call us many times, do not leak memory/fds!
395 static void make_device(char *path, int delete)
397 char *device_name, *subsystem_slash_devname;
398 int major, minor, type, len;
400 dbg("%s('%s', delete:%d)", __func__, path, delete);
402 /* Try to read major/minor string. Note that the kernel puts \n after
403 * the data, so we don't need to worry about null terminating the string
404 * because sscanf() will stop at the first nondigit, which \n is.
405 * We also depend on path having writeable space after it.
409 char *dev_maj_min = path + strlen(path);
411 strcpy(dev_maj_min, "/dev");
412 len = open_read_close(path, dev_maj_min + 1, 64);
415 if (!ENABLE_FEATURE_MDEV_EXEC)
417 /* no "dev" file, but we can still run scripts
418 * based on device name */
419 } else if (sscanf(++dev_maj_min, "%u:%u", &major, &minor) != 2) {
423 /* else: for delete, -1 still deletes the node, but < -1 suppresses that */
425 /* Determine device name, type, major and minor */
426 device_name = (char*) bb_basename(path);
427 /* http://kernel.org/doc/pending/hotplug.txt says that only
428 * "/sys/block/..." is for block devices. "/sys/bus" etc is not.
429 * But since 2.6.25 block devices are also in /sys/class/block.
430 * We use strstr("/block/") to forestall future surprises. */
432 if (strstr(path, "/block/") || (G.subsystem && strncmp(G.subsystem, "block", 5) == 0))
435 /* Make path point to "subsystem/device_name" */
436 subsystem_slash_devname = NULL;
437 /* Check for coldplug invocations first */
438 if (strncmp(path, "/sys/block/", 11) == 0) /* legacy case */
439 path += sizeof("/sys/") - 1;
440 else if (strncmp(path, "/sys/class/", 11) == 0)
441 path += sizeof("/sys/class/") - 1;
443 /* Example of a hotplug invocation:
445 * DEVPATH="/sys" + "/devices/virtual/mtd/mtd3/mtdblock3"
446 * ("/sys" is added by mdev_main)
447 * - path does not contain subsystem
449 subsystem_slash_devname = concat_path_file(G.subsystem, device_name);
450 path = subsystem_slash_devname;
453 #if ENABLE_FEATURE_MDEV_CONF
454 G.rule_idx = 0; /* restart from the beginning (think mdev -s) */
457 const char *str_to_match;
458 regmatch_t off[1 + 9 * ENABLE_FEATURE_MDEV_RENAME_REGEXP];
461 char aliaslink = aliaslink; /* for compiler */
462 const char *node_name;
463 const struct rule *rule;
469 #if ENABLE_FEATURE_MDEV_CONF
470 if (rule->maj >= 0) { /* @maj,min rule */
471 if (major != rule->maj)
473 if (minor < rule->min0 || minor > rule->min1)
475 memset(off, 0, sizeof(off));
478 if (rule->envvar) { /* $envvar=regex rule */
479 str_to_match = getenv(rule->envvar);
480 dbg("getenv('%s'):'%s'", rule->envvar, str_to_match);
484 /* regex to match [subsystem/]device_name */
485 str_to_match = (rule->regex_has_slash ? path : device_name);
488 if (rule->regex_compiled) {
489 int regex_match = regexec(&rule->match, str_to_match, ARRAY_SIZE(off), off, 0);
490 dbg("regex_match for '%s':%d", str_to_match, regex_match);
491 //bb_error_msg("matches:");
492 //for (int i = 0; i < ARRAY_SIZE(off); i++) {
493 // if (off[i].rm_so < 0) continue;
494 // bb_error_msg("match %d: '%.*s'\n", i,
495 // (int)(off[i].rm_eo - off[i].rm_so),
496 // device_name + off[i].rm_so);
500 /* regexec returns whole pattern as "range" 0 */
502 || (int)off[0].rm_eo != (int)strlen(str_to_match)
504 continue; /* this rule doesn't match */
507 /* else: it's final implicit "match-all" rule */
513 /* Build alias name */
515 if (ENABLE_FEATURE_MDEV_RENAME && rule->ren_mov) {
516 aliaslink = rule->ren_mov[0];
517 if (aliaslink == '!') {
518 /* "!": suppress node creation/deletion */
521 else if (aliaslink == '>' || aliaslink == '=') {
522 if (ENABLE_FEATURE_MDEV_RENAME_REGEXP) {
527 /* substitute %1..9 with off[1..9], if any */
534 p = alias = xzalloc(strlen(rule->ren_mov) + n * strlen(str_to_match));
535 s = rule->ren_mov + 1;
539 unsigned i = (s[1] - '0');
540 if (i <= 9 && off[i].rm_so >= 0) {
541 n = off[i].rm_eo - off[i].rm_so;
542 strncpy(p, str_to_match + off[i].rm_so, n);
551 alias = xstrdup(rule->ren_mov + 1);
555 dbg("alias:'%s'", alias);
558 IF_FEATURE_MDEV_EXEC(command = rule->r_cmd;)
560 const char *s = "$@*";
561 const char *s2 = strchr(s, command[0]);
563 /* Are we running this command now?
564 * Run $cmd on delete, @cmd on create, *cmd on both
566 if (s2 - s != delete) {
567 /* We are here if: '*',
568 * or: '@' and delete = 0,
569 * or: '$' and delete = 1
576 dbg("command:'%s'", command);
578 /* "Execute" the line we found */
579 node_name = device_name;
580 if (ENABLE_FEATURE_MDEV_RENAME && alias) {
581 node_name = alias = build_alias(alias, device_name);
582 dbg("alias2:'%s'", alias);
585 if (!delete && major >= 0) {
586 dbg("mknod('%s',%o,(%d,%d))", node_name, rule->mode | type, major, minor);
587 if (mknod(node_name, rule->mode | type, makedev(major, minor)) && errno != EEXIST)
588 bb_perror_msg("can't create '%s'", node_name);
589 if (major == G.root_major && minor == G.root_minor)
590 symlink(node_name, "root");
591 if (ENABLE_FEATURE_MDEV_CONF) {
592 chmod(node_name, rule->mode);
593 chown(node_name, rule->ugid.uid, rule->ugid.gid);
595 if (ENABLE_FEATURE_MDEV_RENAME && alias) {
596 if (aliaslink == '>')
597 symlink(node_name, device_name);
601 if (ENABLE_FEATURE_MDEV_EXEC && command) {
602 /* setenv will leak memory, use putenv/unsetenv/free */
603 char *s = xasprintf("%s=%s", "MDEV", node_name);
604 char *s1 = xasprintf("%s=%s", "SUBSYSTEM", G.subsystem);
607 if (system(command) == -1)
608 bb_perror_msg("can't run '%s'", command);
609 bb_unsetenv_and_free(s1);
610 bb_unsetenv_and_free(s);
613 if (delete && major >= -1) {
614 if (ENABLE_FEATURE_MDEV_RENAME && alias) {
615 if (aliaslink == '>')
621 if (ENABLE_FEATURE_MDEV_RENAME)
624 /* We found matching line.
625 * Stop unless it was prefixed with '-'
627 if (!ENABLE_FEATURE_MDEV_CONF || !rule->keep_matching)
631 free(subsystem_slash_devname);
634 /* File callback for /sys/ traversal */
635 static int FAST_FUNC fileAction(const char *fileName,
636 struct stat *statbuf UNUSED_PARAM,
638 int depth UNUSED_PARAM)
640 size_t len = strlen(fileName) - 4; /* can't underflow */
641 char *scratch = userData;
643 /* len check is for paranoid reasons */
644 if (strcmp(fileName + len, "/dev") != 0 || len >= PATH_MAX)
647 strcpy(scratch, fileName);
649 make_device(scratch, /*delete:*/ 0);
654 /* Directory callback for /sys/ traversal */
655 static int FAST_FUNC dirAction(const char *fileName UNUSED_PARAM,
656 struct stat *statbuf UNUSED_PARAM,
657 void *userData UNUSED_PARAM,
660 /* Extract device subsystem -- the name of the directory
661 * under /sys/class/ */
664 G.subsystem = strrchr(fileName, '/');
666 G.subsystem = xstrdup(G.subsystem + 1);
669 return (depth >= MAX_SYSFS_DEPTH ? SKIP : TRUE);
672 /* For the full gory details, see linux/Documentation/firmware_class/README
674 * Firmware loading works like this:
675 * - kernel sets FIRMWARE env var
676 * - userspace checks /lib/firmware/$FIRMWARE
677 * - userspace waits for /sys/$DEVPATH/loading to appear
678 * - userspace writes "1" to /sys/$DEVPATH/loading
679 * - userspace copies /lib/firmware/$FIRMWARE into /sys/$DEVPATH/data
680 * - userspace writes "0" (worked) or "-1" (failed) to /sys/$DEVPATH/loading
681 * - kernel loads firmware into device
683 static void load_firmware(const char *firmware, const char *sysfs_path)
686 int firmware_fd, loading_fd, data_fd;
688 /* check for /lib/firmware/$FIRMWARE */
689 xchdir("/lib/firmware");
690 firmware_fd = xopen(firmware, O_RDONLY);
692 /* in case we goto out ... */
695 /* check for /sys/$DEVPATH/loading ... give 30 seconds to appear */
697 for (cnt = 0; cnt < 30; ++cnt) {
698 loading_fd = open("loading", O_WRONLY);
699 if (loading_fd != -1)
706 /* tell kernel we're loading by "echo 1 > /sys/$DEVPATH/loading" */
707 if (full_write(loading_fd, "1", 1) != 1)
710 /* load firmware into /sys/$DEVPATH/data */
711 data_fd = open("data", O_WRONLY);
714 cnt = bb_copyfd_eof(firmware_fd, data_fd);
716 /* tell kernel result by "echo [0|-1] > /sys/$DEVPATH/loading" */
718 full_write(loading_fd, "0", 1);
720 full_write(loading_fd, "-1", 2);
723 if (ENABLE_FEATURE_CLEAN_UP) {
730 int mdev_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
731 int mdev_main(int argc UNUSED_PARAM, char **argv)
733 RESERVE_CONFIG_BUFFER(temp, PATH_MAX + SCRATCH_SIZE);
737 #if ENABLE_FEATURE_MDEV_CONF
738 G.filename = "/etc/mdev.conf";
741 /* We can be called as hotplug helper */
742 /* Kernel cannot provide suitable stdio fds for us, do it ourself */
745 /* Force the configuration file settings exactly */
750 if (argv[1] && strcmp(argv[1], "-s") == 0) {
756 #if ENABLE_FEATURE_MDEV_CONF
757 /* Same as xrealloc_vector(NULL, 4, 0): */
758 G.rule_vec = xzalloc((1 << 4) * sizeof(*G.rule_vec));
761 G.root_major = major(st.st_dev);
762 G.root_minor = minor(st.st_dev);
764 /* ACTION_FOLLOWLINKS is needed since in newer kernels
765 * /sys/block/loop* (for example) are symlinks to dirs,
766 * not real directories.
767 * (kernel's CONFIG_SYSFS_DEPRECATED makes them real dirs,
768 * but we can't enforce that on users)
770 if (access("/sys/class/block", F_OK) != 0) {
771 /* Scan obsolete /sys/block only if /sys/class/block
772 * doesn't exist. Otherwise we'll have dupes.
773 * Also, do not complain if it doesn't exist.
774 * Some people configure kernel to have no blockdevs.
776 recursive_action("/sys/block",
777 ACTION_RECURSE | ACTION_FOLLOWLINKS | ACTION_QUIET,
778 fileAction, dirAction, temp, 0);
780 recursive_action("/sys/class",
781 ACTION_RECURSE | ACTION_FOLLOWLINKS,
782 fileAction, dirAction, temp, 0);
788 static const char keywords[] ALIGN1 = "remove\0add\0";
789 enum { OP_remove = 0, OP_add };
793 * env ACTION=... DEVPATH=... SUBSYSTEM=... [SEQNUM=...] mdev
794 * ACTION can be "add" or "remove"
795 * DEVPATH is like "/block/sda" or "/class/input/mice"
797 action = getenv("ACTION");
798 env_path = getenv("DEVPATH");
799 G.subsystem = getenv("SUBSYSTEM");
800 if (!action || !env_path /*|| !G.subsystem*/)
802 fw = getenv("FIRMWARE");
803 op = index_in_strings(keywords, action);
804 /* If it exists, does /dev/mdev.seq match $SEQNUM?
805 * If it does not match, earlier mdev is running
806 * in parallel, and we need to wait */
807 seq = getenv("SEQNUM");
809 int timeout = 2000 / 32; /* 2000 msec */
812 char seqbuf[sizeof(int)*3 + 2];
814 seqlen = open_read_close("mdev.seq", seqbuf, sizeof(seqbuf-1));
819 seqbuf[seqlen] = '\0';
820 if (seqbuf[0] == '\n' /* seed file? */
821 || strcmp(seq, seqbuf) == 0 /* correct idx? */
829 snprintf(temp, PATH_MAX, "/sys%s", env_path);
830 if (op == OP_remove) {
831 /* Ignoring "remove firmware". It was reported
832 * to happen and to cause erroneous deletion
833 * of device nodes. */
835 make_device(temp, /*delete:*/ 1);
837 else if (op == OP_add) {
838 make_device(temp, /*delete:*/ 0);
839 if (ENABLE_FEATURE_MDEV_LOAD_FIRMWARE) {
841 load_firmware(fw, temp);
846 xopen_xwrite_close("mdev.seq", utoa(xatou(seq) + 1));
850 if (ENABLE_FEATURE_CLEAN_UP)
851 RELEASE_CONFIG_BUFFER(temp);