udevcontrol: allow to set global variables in udevd

The initial patch is from Harald, possible new bugs are from me.

5 files changed, 91 insertions, 57 deletions

diff --git a/udevcontrol.c b/udevcontrol.c
index 6ca90855c5..b20ce2e071 100644
--- a/udevcontrol.c
+++ b/udevcontrol.c
@@ -54,9 +54,9 @@ int main(int argc, char *argv[], char *envp[])
 	struct sockaddr_un saddr;
 	socklen_t addrlen;
 	const char *env;
+	const char *arg;
 	const char *val;
 	int *intval;
-	int i;
 	int retval = 1;
 
 	env = getenv("UDEV_LOG");
@@ -70,67 +70,73 @@ int main(int argc, char *argv[], char *envp[])
 		fprintf(stderr, "missing command\n\n");
 		goto exit;
 	}
-
 	memset(&ctrl_msg, 0x00, sizeof(struct udevd_ctrl_msg));
 	strcpy(ctrl_msg.magic, UDEVD_CTRL_MAGIC);
-
-	for (i = 1 ; i < argc; i++) {
-		char *arg = argv[i];
-
-		if (!strcmp(arg, "stop_exec_queue"))
-			ctrl_msg.type = UDEVD_CTRL_STOP_EXEC_QUEUE;
-		else if (!strcmp(arg, "start_exec_queue"))
-			ctrl_msg.type = UDEVD_CTRL_START_EXEC_QUEUE;
-		else if (!strcmp(arg, "reload_rules"))
-			ctrl_msg.type = UDEVD_CTRL_RELOAD_RULES;
-		else if (!strncmp(arg, "log_priority=", strlen("log_priority="))) {
-			intval = (int *) ctrl_msg.buf;
-			val = &arg[strlen("log_priority=")];
-			ctrl_msg.type = UDEVD_CTRL_SET_LOG_LEVEL;
-			*intval = log_priority(val);
-			info("send log_priority=%i", *intval);
-		} else if (!strncmp(arg, "max_childs=", strlen("max_childs="))) {
-			char *endp;
-			int count;
-
-			intval = (int *) ctrl_msg.buf;
-			val = &arg[strlen("max_childs=")];
-			ctrl_msg.type = UDEVD_CTRL_SET_MAX_CHILDS;
-			count = strtoul(val, &endp, 0);
-			if (endp[0] != '\0' || count < 1) {
-				fprintf(stderr, "invalid number\n");
-				goto exit;
-			}
-			*intval = count;
-			info("send max_childs=%i", *intval);
-		} else if (!strncmp(arg, "max_childs_running=", strlen("max_childs_running="))) {
-			char *endp;
-			int count;
-
-			intval = (int *) ctrl_msg.buf;
-			val = &arg[strlen("max_childs_running=")];
-			ctrl_msg.type = UDEVD_CTRL_SET_MAX_CHILDS_RUNNING;
-			count = strtoul(val, &endp, 0);
-			if (endp[0] != '\0' || count < 1) {
-				fprintf(stderr, "invalid number\n");
-				goto exit;
-			}
-			*intval = count;
-			info("send max_childs_running=%i", *intval);
-		} else if (strcmp(arg, "help") == 0  || strcmp(arg, "--help") == 0  || strcmp(arg, "-h") == 0) {
-			printf("Usage: udevcontrol COMMAND\n"
-				"  log_priority=<level>   set the udev log level for the daemon\n"
-				"  stop_exec_queue        keep udevd from executing events, queue only\n"
-				"  start_exec_queue       execute events, flush queue\n"
-				"  reload_rules           reloads the rules files\n"
-				"  max_childs=<N>         maximum number of childs\n"
-				"  max_childs_running=<N> maximum number of childs running at the same time\n"
-				"  help                   print this help text\n\n");
+	arg = argv[1];
+
+	if (!strcmp(arg, "stop_exec_queue"))
+		ctrl_msg.type = UDEVD_CTRL_STOP_EXEC_QUEUE;
+	else if (!strcmp(arg, "start_exec_queue"))
+		ctrl_msg.type = UDEVD_CTRL_START_EXEC_QUEUE;
+	else if (!strcmp(arg, "reload_rules"))
+		ctrl_msg.type = UDEVD_CTRL_RELOAD_RULES;
+	else if (!strncmp(arg, "log_priority=", strlen("log_priority="))) {
+		intval = (int *) ctrl_msg.buf;
+		val = &arg[strlen("log_priority=")];
+		ctrl_msg.type = UDEVD_CTRL_SET_LOG_LEVEL;
+		*intval = log_priority(val);
+		info("send log_priority=%i", *intval);
+	} else if (!strncmp(arg, "max_childs=", strlen("max_childs="))) {
+		char *endp;
+		int count;
+
+		intval = (int *) ctrl_msg.buf;
+		val = &arg[strlen("max_childs=")];
+		ctrl_msg.type = UDEVD_CTRL_SET_MAX_CHILDS;
+		count = strtoul(val, &endp, 0);
+		if (endp[0] != '\0' || count < 1) {
+			fprintf(stderr, "invalid number\n");
+			goto exit;
+		}
+		*intval = count;
+		info("send max_childs=%i", *intval);
+	} else if (!strncmp(arg, "max_childs_running=", strlen("max_childs_running="))) {
+		char *endp;
+		int count;
+
+		intval = (int *) ctrl_msg.buf;
+		val = &arg[strlen("max_childs_running=")];
+		ctrl_msg.type = UDEVD_CTRL_SET_MAX_CHILDS_RUNNING;
+		count = strtoul(val, &endp, 0);
+		if (endp[0] != '\0' || count < 1) {
+			fprintf(stderr, "invalid number\n");
 			goto exit;
-		} else {
-			fprintf(stderr, "unrecognized command '%s'\n", arg);
+		}
+		*intval = count;
+		info("send max_childs_running=%i", *intval);
+	} else if (!strncmp(arg, "env", strlen("env"))) {
+		val = argv[2];
+		if (val == NULL) {
+			fprintf(stderr, "missing key\n");
 			goto exit;
 		}
+		ctrl_msg.type = UDEVD_CTRL_ENV;
+		strlcpy(ctrl_msg.buf, val, sizeof(ctrl_msg.buf));
+		info("send env '%s'", val);
+	} else if (strcmp(arg, "help") == 0  || strcmp(arg, "--help") == 0  || strcmp(arg, "-h") == 0) {
+		printf("Usage: udevcontrol COMMAND\n"
+			"  log_priority=<level>   set the udev log level for the daemon\n"
+			"  stop_exec_queue        keep udevd from executing events, queue only\n"
+			"  start_exec_queue       execute events, flush queue\n"
+			"  reload_rules           reloads the rules files\n"
+			"  env <var>=<value>      set a global environment variable\n"
+			"  max_childs=<N>         maximum number of childs\n"
+			"  max_childs_running=<N> maximum number of childs running at the same time\n"
+			"  help                   print this help text\n\n");
+		goto exit;
+	} else {
+		fprintf(stderr, "unrecognized command '%s'\n", arg);
+		goto exit;
 	}
 
 	if (getuid() != 0) {
diff --git a/udevd.8 b/udevd.8
index 614e4f338f..25996d1c8d 100644
--- a/udevd.8
+++ b/udevd.8
@@ -71,6 +71,11 @@ Signal udevd to enable the execution of events.
 Signal udevd to reload the rules from the config.
 .RE
 .PP
+\fBenv \fR\fB\fIvar\fR\fR\fB=\fR\fB\fIvalue\fR\fR
+.RS 4
+Set global variable.
+.RE
+.PP
 \fBmax_childs\fR
 .RS 4
 Set the maximum number of events, udevd will handle at the same time.
diff --git a/udevd.c b/udevd.c
index dccc745eff..645b068c0e 100644
--- a/udevd.c
+++ b/udevd.c
@@ -667,6 +667,7 @@ static void get_ctrl_msg(void)
 	struct ucred *cred;
 	char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
 	int *intval;
+	char *pos;
 
 	memset(&ctrl_msg, 0x00, sizeof(struct udevd_ctrl_msg));
 	iov.iov_base = &ctrl_msg;
@@ -703,6 +704,21 @@ static void get_ctrl_msg(void)
 	}
 
 	switch (ctrl_msg.type) {
+	case UDEVD_CTRL_ENV:
+		pos = strchr(ctrl_msg.buf, '=');
+		if (pos == NULL) {
+			err("wrong key format '%s'", ctrl_msg.buf);
+			break;
+		}
+		pos[0] = '\0';
+		if (pos[1] == '\0') {
+			info("udevd message (ENV) received, unset '%s'", ctrl_msg.buf);
+			unsetenv(ctrl_msg.buf);
+		} else {
+			info("udevd message (ENV) received, set '%s=%s'", ctrl_msg.buf, &pos[1]);
+			setenv(ctrl_msg.buf, &pos[1], 1);
+		}
+		break;
 	case UDEVD_CTRL_STOP_EXEC_QUEUE:
 		info("udevd message (STOP_EXEC_QUEUE) received");
 		stop_exec_q = 1;
diff --git a/udevd.h b/udevd.h
index fce86e7126..4ca6d1dcf2 100644
--- a/udevd.h
+++ b/udevd.h
@@ -46,6 +46,7 @@ enum udevd_ctrl_msg_type {
 	UDEVD_CTRL_SET_MAX_CHILDS,
 	UDEVD_CTRL_SET_MAX_CHILDS_RUNNING,
 	UDEVD_CTRL_RELOAD_RULES,
+	UDEVD_CTRL_ENV,
 };
 
 struct udevd_ctrl_msg {
diff --git a/udevd.xml b/udevd.xml
index 674fa4d755..cf033a06b2 100644
--- a/udevd.xml
+++ b/udevd.xml
@@ -105,6 +105,12 @@
             </listitem>
           </varlistentry>
           <varlistentry>
+            <term><option>env <replaceable>var</replaceable>=<replaceable>value</replaceable></option></term>
+            <listitem>
+              <para>Set global variable.</para>
+            </listitem>
+          </varlistentry>
+          <varlistentry>
             <term><option>max_childs</option></term>
             <listitem>
               <para>Set the maximum number of events, udevd will handle at the