busybox 1.21.0: update mdev patch

--- busybox-1.21.0/util-linux/mdev.c

+++ busybox-1.21.0-mdev/util-linux/mdev.c

@@ -661,6 +661,8 @@ static void make_device(char *device_nam

@@ -80,7 +80,7 @@

 //usage:	IF_FEATURE_MDEV_CONF(

 //usage:       "\n"

 //usage:       "It uses /etc/mdev.conf with lines\n"

-//usage:       "	[-]DEVNAME UID:GID PERM"

+//usage:       "	[-][ENV=regex;]...DEVNAME UID:GID PERM"

 //usage:			IF_FEATURE_MDEV_RENAME(" [>|=PATH]|[!]")

 //usage:			IF_FEATURE_MDEV_EXEC(" [@|$|*PROG]")

 //usage:       "\n"

@@ -230,9 +230,34 @@

  * SUBSYSTEM=block

  */

-static const char keywords[] ALIGN1 = "add\0remove\0change\0";

+#define DEBUG_LVL 2

+

+#if DEBUG_LVL >= 1

+# define dbg1(...) do { if (G.verbose) bb_error_msg(__VA_ARGS__); } while(0)

+#else

+# define dbg1(...) ((void)0)

+#endif

+#if DEBUG_LVL >= 2

+# define dbg2(...) do { if (G.verbose >= 2) bb_error_msg(__VA_ARGS__); } while(0)

+#else

+# define dbg2(...) ((void)0)

+#endif

+#if DEBUG_LVL >= 3

+# define dbg3(...) do { if (G.verbose >= 3) bb_error_msg(__VA_ARGS__); } while(0)

+#else

+# define dbg3(...) ((void)0)

+#endif

+

+

+static const char keywords[] ALIGN1 = "add\0remove\0"; // "change\0"

 enum { OP_add, OP_remove };

+struct envmatch {

+	struct envmatch *next;

+	char *envname;

+	regex_t match;

+};

+

 struct rule {

 	bool keep_matching;

 	bool regex_compiled;

@@ -243,12 +268,14 @@ struct rule {

 	char *ren_mov;

 	IF_FEATURE_MDEV_EXEC(char *r_cmd;)

 	regex_t match;

+	struct envmatch *envmatch;

 };

 struct globals {

 	int root_major, root_minor;

 	smallint verbose;

 	char *subsystem;

+	char *subsys_env; /* for putenv("SUBSYSTEM=subsystem") */

 #if ENABLE_FEATURE_MDEV_CONF

 	const char *filename;

 	parser_t *parser;

@@ -256,6 +283,7 @@ struct globals {

 	unsigned rule_idx;

 #endif

 	struct rule cur_rule;

+	char timestr[sizeof("60.123456")];

 } FIX_ALIASING;

 #define G (*(struct globals*)&bb_common_bufsiz1)

 #define INIT_G() do { \

@@ -270,13 +298,6 @@ struct globals {

 /* We use additional 64+ bytes in make_device() */

 #define SCRATCH_SIZE 80

-#if 0

-# define dbg(...) bb_error_msg(__VA_ARGS__)

-#else

-# define dbg(...) ((void)0)

-#endif

-

-

 #if ENABLE_FEATURE_MDEV_CONF

 static void make_default_cur_rule(void)

@@ -288,14 +309,65 @@ static void make_default_cur_rule(void)

 static void clean_up_cur_rule(void)

 {

+	struct envmatch *e;

+

 	free(G.cur_rule.envvar);

+	free(G.cur_rule.ren_mov);

 	if (G.cur_rule.regex_compiled)

 		regfree(&G.cur_rule.match);

-	free(G.cur_rule.ren_mov);

 	IF_FEATURE_MDEV_EXEC(free(G.cur_rule.r_cmd);)

+	e = G.cur_rule.envmatch;

+	while (e) {

+		free(e->envname);

+		regfree(&e->match);

+		e = e->next;

+	}

 	make_default_cur_rule();

 }

+/* In later versions, endofname is in libbb */

+#define endofname mdev_endofname

+static

+const char* FAST_FUNC

+endofname(const char *name)

+{

+#define is_name(c)      ((c) == '_' || isalpha((unsigned char)(c)))

+#define is_in_name(c)   ((c) == '_' || isalnum((unsigned char)(c)))

+	if (!is_name(*name))

+		return name;

+	while (*++name) {

+		if (!is_in_name(*name))

+			break;

+	}

+	return name;

+}

+

+static char *parse_envmatch_pfx(char *val)

+{

+	struct envmatch **nextp = &G.cur_rule.envmatch;

+

+	for (;;) {

+		struct envmatch *e;

+		char *semicolon;

+		char *eq = strchr(val, '=');

+		if (!eq /* || eq == val? */)

+			return val;

+		if (endofname(val) != eq)

+			return val;

+		semicolon = strchr(eq, ';');

+		if (!semicolon)

+			return val;

+		/* ENVVAR=regex;... */

+		*nextp = e = xzalloc(sizeof(*e));

+		nextp = &e->next;

+		e->envname = xstrndup(val, eq - val);

+		*semicolon = '\0';

+		xregcomp(&e->match, eq + 1, REG_EXTENDED);

+		*semicolon = ';';

+		val = semicolon + 1;

+	}

+}

+

 static void parse_next_rule(void)

 {

 	/* Note: on entry, G.cur_rule is set to default */

@@ -308,12 +380,13 @@ static void parse_next_rule(void)

 			break;

 		/* Fields: [-]regex uid:gid mode [alias] [cmd] */

-		dbg("token1:'%s'", tokens[1]);

+		dbg3("token1:'%s'", tokens[1]);

 		/* 1st field */

 		val = tokens[0];

 		G.cur_rule.keep_matching = ('-' == val[0]);

 		val += G.cur_rule.keep_matching; /* swallow leading dash */

+		val = parse_envmatch_pfx(val);

 		if (val[0] == '@') {

 			/* @major,minor[-minor2] */

 			/* (useful when name is ambiguous:

@@ -328,8 +401,10 @@ static void parse_next_rule(void)

 			if (sc == 2)

 				G.cur_rule.min1 = G.cur_rule.min0;

 		} else {

+			char *eq = strchr(val, '=');

 			if (val[0] == '$') {

-				char *eq = strchr(++val, '=');

+				/* $ENVVAR=regex ... */

+				val++;

 				if (!eq) {

 					bb_error_msg("bad $envvar=regex on line %d", G.parser->lineno);

 					goto next_rule;

@@ -373,7 +448,7 @@ static void parse_next_rule(void)

 		clean_up_cur_rule();

 	} /* while (config_read) */

-	dbg("config_close(G.parser)");

+	dbg3("config_close(G.parser)");

 	config_close(G.parser);

 	G.parser = NULL;

@@ -390,7 +465,7 @@ static const struct rule *next_rule(void

 	/* Open conf file if we didn't do it yet */

 	if (!G.parser && G.filename) {

-		dbg("config_open('%s')", G.filename);

+		dbg3("config_open('%s')", G.filename);

 		G.parser = config_open2(G.filename, fopen_for_read);

 		G.filename = NULL;

 	}

@@ -399,7 +474,7 @@ static const struct rule *next_rule(void

 		/* mdev -s */

 		/* Do we have rule parsed already? */

 		if (G.rule_vec[G.rule_idx]) {

-			dbg("< G.rule_vec[G.rule_idx:%d]=%p", G.rule_idx, G.rule_vec[G.rule_idx]);

+			dbg3("< G.rule_vec[G.rule_idx:%d]=%p", G.rule_idx, G.rule_vec[G.rule_idx]);

 			return G.rule_vec[G.rule_idx++];

 		}

 		make_default_cur_rule();

@@ -416,13 +491,28 @@ static const struct rule *next_rule(void

 			rule = memcpy(xmalloc(sizeof(G.cur_rule)), &G.cur_rule, sizeof(G.cur_rule));

 			G.rule_vec = xrealloc_vector(G.rule_vec, 4, G.rule_idx);

 			G.rule_vec[G.rule_idx++] = rule;

-			dbg("> G.rule_vec[G.rule_idx:%d]=%p", G.rule_idx, G.rule_vec[G.rule_idx]);

+			dbg3("> G.rule_vec[G.rule_idx:%d]=%p", G.rule_idx, G.rule_vec[G.rule_idx]);

 		}

 	}

 	return rule;

 }

+static int env_matches(struct envmatch *e)

+{

+	while (e) {

+		int r;

+		char *val = getenv(e->envname);

+		if (!val)

+			return 0;

+		r = regexec(&e->match, val, /*size*/ 0, /*range[]*/ NULL, /*eflags*/ 0);

+		if (r != 0) /* no match */

+			return 0;

+		e = e->next;

+	}

+	return 1;

+}

+

 #else

 # define next_rule() (&G.cur_rule)

@@ -479,9 +569,6 @@ static void make_device(char *device_nam

 {

 	int major, minor, type, len;

-	if (G.verbose)

-		bb_error_msg("device: %s, %s", device_name, path);

-

 	/* 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.

@@ -500,8 +587,7 @@ static void make_device(char *device_nam

 			/* no "dev" file, but we can still run scripts

 			 * based on device name */

 		} else if (sscanf(++dev_maj_min, "%u:%u", &major, &minor) == 2) {

-			if (G.verbose)

-				bb_error_msg("maj,min: %u,%u", major, minor);

+			dbg1("dev %u,%u", major, minor);

 		} else {

 			major = -1;

 		}

@@ -511,7 +597,8 @@ static void make_device(char *device_nam

 	/* Determine device name, type, major and minor */

 	if (!device_name)

 		device_name = (char*) bb_basename(path);

-	/* http://kernel.org/doc/pending/hotplug.txt says that only

+	/*

+	 * http://kernel.org/doc/pending/hotplug.txt says that only

 	 * "/sys/block/..." is for block devices. "/sys/bus" etc is not.

 	 * But since 2.6.25 block devices are also in /sys/class/block.

 	 * We use strstr("/block/") to forestall future surprises.

@@ -537,6 +624,8 @@ static void make_device(char *device_nam

 		rule = next_rule();

 #if ENABLE_FEATURE_MDEV_CONF

+		if (!env_matches(rule->envmatch))

+			continue;

 		if (rule->maj >= 0) {  /* @maj,min rule */

 			if (major != rule->maj)

 				continue;

@@ -547,7 +636,7 @@ static void make_device(char *device_nam

 		}

 		if (rule->envvar) { /* $envvar=regex rule */

 			str_to_match = getenv(rule->envvar);

-			dbg("getenv('%s'):'%s'", rule->envvar, str_to_match);

+			dbg3("getenv('%s'):'%s'", rule->envvar, str_to_match);

 			if (!str_to_match)

 				continue;

 		}

@@ -555,7 +644,7 @@ static void make_device(char *device_nam

 		if (rule->regex_compiled) {

 			int regex_match = regexec(&rule->match, str_to_match, ARRAY_SIZE(off), off, 0);

-			dbg("regex_match for '%s':%d", str_to_match, regex_match);

+			dbg3("regex_match for '%s':%d", str_to_match, regex_match);

 			//bb_error_msg("matches:");

 			//for (int i = 0; i < ARRAY_SIZE(off); i++) {

 			//	if (off[i].rm_so < 0) continue;

@@ -574,9 +663,8 @@ static void make_device(char *device_nam

 		}

 		/* else: it's final implicit "match-all" rule */

  rule_matches:

+		dbg2("rule matched, line %d", G.parser ? G.parser->lineno : -1);

 #endif

-		dbg("rule matched");

-

 		/* Build alias name */

 		alias = NULL;

 		if (ENABLE_FEATURE_MDEV_RENAME && rule->ren_mov) {

@@ -619,34 +707,30 @@ static void make_device(char *device_nam

 				}

 			}

 		}

-		dbg("alias:'%s'", alias);

+		dbg3("alias:'%s'", alias);

 		command = NULL;

 		IF_FEATURE_MDEV_EXEC(command = rule->r_cmd;)

 		if (command) {

-			const char *s = "$@*";

-			const char *s2 = strchr(s, command[0]);

-

 			/* Are we running this command now?

-			 * Run $cmd on delete, @cmd on create, *cmd on both

+			 * Run @cmd on create, $cmd on delete, *cmd on any

 			 */

-			if (s2 - s != (operation == OP_remove) || *s2 == '*') {

-				/* We are here if: '*',

-				 * or: '@' and delete = 0,

-				 * or: '$' and delete = 1

-				 */

+			if ((command[0] == '@' && operation == OP_add)

+			 || (command[0] == '$' && operation == OP_remove)

+			 || (command[0] == '*')

+			) {

 				command++;

 			} else {

 				command = NULL;

 			}

 		}

-		dbg("command:'%s'", command);

+		dbg3("command:'%s'", command);

 		/* "Execute" the line we found */

 		node_name = device_name;

 		if (ENABLE_FEATURE_MDEV_RENAME && alias) {

 			node_name = alias = build_alias(alias, device_name);

-			dbg("alias2:'%s'", alias);

+			dbg3("alias2:'%s'", alias);

 		}

 		if (operation == OP_add && major >= 0) {

@@ -656,8 +740,17 @@ static void make_device(char *device_nam

 				mkdir_recursive(node_name);

 				*slash = '/';

 			}

-			if (G.verbose)

-				bb_error_msg("mknod: %s (%d,%d) %o", node_name, major, minor, rule->mode | type);

+			if (ENABLE_FEATURE_MDEV_CONF) {

+				dbg1("mknod %s (%d,%d) %o"

+					" %u:%u",

+					node_name, major, minor, rule->mode | type,

+					rule->ugid.uid, rule->ugid.gid

+				);

+			} else {

+				dbg1("mknod %s (%d,%d) %o",

+					node_name, major, minor, rule->mode | type

+				);

+			}

 			if (mknod(node_name, rule->mode | type, makedev(major, minor)) && errno != EEXIST)

 				bb_perror_msg("can't create '%s'", node_name);

 			if (ENABLE_FEATURE_MDEV_CONF) {

+				if (G.verbose)

+					bb_error_msg("chmod: %o chown: %u:%u", rule->mode, rule->ugid.uid, rule->ugid.gid);

 				chmod(node_name, rule->mode);

 				chown(node_name, rule->ugid.uid, rule->ugid.gid);

@@ -671,8 +764,7 @@ static void make_device(char *device_nam

 //TODO: on devtmpfs, device_name already exists and symlink() fails.

 //End result is that instead of symlink, we have two nodes.

 //What should be done?

-					if (G.verbose)

-						bb_error_msg("symlink: %s", device_name);

+					dbg1("symlink: %s", device_name);

 					symlink(node_name, device_name);

 				}

 			}

@@ -681,27 +773,21 @@ static void make_device(char *device_nam

 		if (ENABLE_FEATURE_MDEV_EXEC && command) {

 			/* setenv will leak memory, use putenv/unsetenv/free */

 			char *s = xasprintf("%s=%s", "MDEV", node_name);

-			char *s1 = xasprintf("%s=%s", "SUBSYSTEM", G.subsystem);

 			putenv(s);

-			putenv(s1);

-			if (G.verbose)

-				bb_error_msg("running: %s", command);

+			dbg1("running: %s", command);

 			if (system(command) == -1)

 				bb_perror_msg("can't run '%s'", command);

-			bb_unsetenv_and_free(s1);

 			bb_unsetenv_and_free(s);

 		}

 		if (operation == OP_remove && major >= -1) {

 			if (ENABLE_FEATURE_MDEV_RENAME && alias) {

 				if (aliaslink == '>') {

-					if (G.verbose)

-						bb_error_msg("unlink: %s", device_name);

+					dbg1("unlink: %s", device_name);

 					unlink(device_name);

 				}

 			}

@@ -813,6 +815,7 @@ static void load_firmware(const char *fi

-			if (G.verbose)

-				bb_error_msg("unlink: %s", node_name);

+			dbg1("unlink: %s", node_name);

 			unlink(node_name);

 		}

@@ -746,9 +832,16 @@ static int FAST_FUNC dirAction(const cha

 	 * under /sys/class/ */

 	if (1 == depth) {

 		free(G.subsystem);

+		if (G.subsys_env) {

+			bb_unsetenv_and_free(G.subsys_env);

+			G.subsys_env = NULL;

+		}

 		G.subsystem = strrchr(fileName, '/');

-		if (G.subsystem)

+		if (G.subsystem) {

 			G.subsystem = xstrdup(G.subsystem + 1);

+			G.subsys_env = xasprintf("%s=%s", "SUBSYSTEM", G.subsystem);

+			putenv(G.subsys_env);

+		}

 	}

 	return (depth >= MAX_SYSFS_DEPTH ? SKIP : TRUE);

@@ -813,12 +906,107 @@ static void load_firmware(const char *fi

 		full_write(loading_fd, "-1", 2);

  out:

 	if (ENABLE_FEATURE_CLEAN_UP) {

 		close(firmware_fd);

 		close(loading_fd);

@@ -919,11 +922,13 @@ int mdev_main(int argc UNUSED_PARAM, cha

 	}

 }

+static char *curtime(void)

+{

+	struct timeval tv;

+	gettimeofday(&tv, NULL);

+	sprintf(G.timestr, "%u.%06u", (unsigned)tv.tv_sec % 60, (unsigned)tv.tv_usec);

+	return G.timestr;

+}

+

+static void open_mdev_log(const char *seq, unsigned my_pid)

+{

+	int logfd = open("mdev.log", O_WRONLY | O_APPEND);

+	if (logfd >= 0) {

+		xmove_fd(logfd, STDERR_FILENO);

+		G.verbose = 2;

+		applet_name = xasprintf("%s[%s]", applet_name, seq ? seq : utoa(my_pid));

+	}

+}

+

+/* If it exists, does /dev/mdev.seq match $SEQNUM?

+ * If it does not match, earlier mdev is running

+ * in parallel, and we need to wait.

+ * Active mdev pokes us with SIGCHLD to check the new file.

+ */

+static int

+wait_for_seqfile(const char *seq)

+{

+	/* We time out after 2 sec */

+	static const struct timespec ts = { 0, 32*1000*1000 };

+	int timeout = 2000 / 32;

+	int seq_fd = -1;

+	int do_once = 1;

+	sigset_t set_CHLD;

+

+	sigemptyset(&set_CHLD);

+	sigaddset(&set_CHLD, SIGCHLD);

+	sigprocmask(SIG_BLOCK, &set_CHLD, NULL);

+

+	for (;;) {

+		int seqlen;

+		char seqbuf[sizeof(int)*3 + 2];

+

+		if (seq_fd < 0) {

+			seq_fd = open("mdev.seq", O_RDWR);

+			if (seq_fd < 0)

+				break;

+		}

+		seqlen = pread(seq_fd, seqbuf, sizeof(seqbuf) - 1, 0);

+		if (seqlen < 0) {

+			close(seq_fd);

+			seq_fd = -1;

+			break;

+		}

+		seqbuf[seqlen] = '\0';

+		if (seqbuf[0] == '\n') {

+			/* seed file: write out seq ASAP */

+			xwrite_str(seq_fd, seq);

+			xlseek(seq_fd, 0, SEEK_SET);

+			dbg2("first seq written");

+			break;

+		}

+		if (strcmp(seq, seqbuf) == 0) {

+			/* correct idx */

+			break;

+		}

+		if (do_once) {

+			dbg2("%s waiting for '%s'", curtime(), seqbuf);

+			do_once = 0;

+		}

+		if (sigtimedwait(&set_CHLD, NULL, &ts) >= 0) {

+			dbg3("woken up");

+			continue; /* don't decrement timeout! */

+		}

+		if (--timeout == 0) {

+			dbg1("%s waiting for '%s'", "timed out", seqbuf);

+			break;

+		}

+	}

+	sigprocmask(SIG_UNBLOCK, &set_CHLD, NULL);

+	return seq_fd;

+}

+

+static void signal_mdevs(unsigned my_pid)

+{

+	procps_status_t* p = NULL;

+	while ((p = procps_scan(p, PSSCAN_ARGV0)) != NULL) {

+		if (p->pid != my_pid

+		 && p->argv0

+		 && strcmp(bb_basename(p->argv0), "mdev") == 0

+		) {

+			kill(p->pid, SIGCHLD);

+		}

+	}

+}

+

 int mdev_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;

 int mdev_main(int argc UNUSED_PARAM, char **argv)

 {

@@ -840,8 +1028,8 @@ int mdev_main(int argc UNUSED_PARAM, cha

 	xchdir("/dev");

 	if (argv[1] && strcmp(argv[1], "-s") == 0) {

-		/* Scan:

-		 * mdev -s

+		/*

+		 * Scan: mdev -s

 		 */

 		struct stat st;

@@ -853,6 +1041,8 @@ int mdev_main(int argc UNUSED_PARAM, cha

 		G.root_major = major(st.st_dev);

 		G.root_minor = minor(st.st_dev);

+		putenv((char*)"ACTION=add");

+

 		/* ACTION_FOLLOWLINKS is needed since in newer kernels

 		 * /sys/block/loop* (for example) are symlinks to dirs,

 		 * not real directories.

@@ -878,11 +1068,13 @@ int mdev_main(int argc UNUSED_PARAM, cha

 		char *action;

 		char *env_devname;

 		char *env_devpath;

+		unsigned my_pid;

+		int seq_fd;

 		smalluint op;

 		/* Hotplug:

 		 * env ACTION=... DEVPATH=... SUBSYSTEM=... [SEQNUM=...] mdev

-		 * ACTION can be "add" or "remove"

+		 * ACTION can be "add", "remove", "change"

 		 * DEVPATH is like "/block/sda" or "/class/input/mice"

 		 */

 		action = getenv("ACTION");

@@ -893,39 +1085,20 @@ int mdev_main(int argc UNUSED_PARAM, cha

 		if (!action || !env_devpath /*|| !G.subsystem*/)

 			bb_show_usage();

 		fw = getenv("FIRMWARE");

-		/* If it exists, does /dev/mdev.seq match $SEQNUM?

-		 * If it does not match, earlier mdev is running

-		 * in parallel, and we need to wait */

 		seq = getenv("SEQNUM");

-		if (seq) {

-			int timeout = 2000 / 32; /* 2000 msec */

-			do {

-				int seqlen;

-				char seqbuf[sizeof(int)*3 + 2];

-

-				seqlen = open_read_close("mdev.seq", seqbuf, sizeof(seqbuf) - 1);

-				if (seqlen < 0) {

-					seq = NULL;

-					break;

-				}

-				seqbuf[seqlen] = '\0';

-				if (seqbuf[0] == '\n' /* seed file? */

-				 || strcmp(seq, seqbuf) == 0 /* correct idx? */

-				) {

-					break;

-				}

-				usleep(32*1000);

-			} while (--timeout);

-		}

-		{

-			int logfd = open("/dev/mdev.log", O_WRONLY | O_APPEND);

+			int logfd = open("mdev.log", O_WRONLY | O_APPEND);

 			if (logfd >= 0) {

 				xmove_fd(logfd, STDERR_FILENO);

 				G.verbose = 1;

-			if (logfd >= 0) {

-				xmove_fd(logfd, STDERR_FILENO);

-				G.verbose = 1;

-				bb_error_msg("seq: %s action: %s", seq, action);

+				if (seq)

+					applet_name = xasprintf("%s[%s]", applet_name, seq);

+				bb_error_msg("action: %s", action);

-			}

-		}

+		my_pid = getpid();

+		open_mdev_log(seq, my_pid);

+

+		seq_fd = seq ? wait_for_seqfile(seq) : -1;

+

+		dbg1("%s "

+			"ACTION:%s SUBSYSTEM:%s DEVNAME:%s DEVPATH:%s"

+			"%s%s",

+			curtime(),

+			action, G.subsystem, env_devname, env_devpath,

+			fw ? " FW:" : "", fw ? fw : ""

+		);

 		snprintf(temp, PATH_MAX, "/sys%s", env_devpath);

 		if (op == OP_remove) {

@@ -935,16 +1108,18 @@ int mdev_main(int argc UNUSED_PARAM, cha

 			if (!fw)

 				make_device(env_devname, temp, op);

 		}

-		else if (op == OP_add) {

+		else {

 			make_device(env_devname, temp, op);

 			if (ENABLE_FEATURE_MDEV_LOAD_FIRMWARE) {

-				if (fw)

+				if (op == OP_add && fw)

 					load_firmware(fw, temp);

 			}

 		}

-		if (seq) {

-			xopen_xwrite_close("mdev.seq", utoa(xatou(seq) + 1));

+		dbg1("%s exiting", curtime());

+		if (seq_fd >= 0) {

+			xwrite_str(seq_fd, utoa(xatou(seq) + 1));

+			signal_mdevs(my_pid);

 		}

 	}