udevadm-control: parse all args in advance

This is mostly just refactoring to make the code more manageable and
extendable. It doesn't introduce any semantic changes, but it
"optimizes" the communication with udevd a bit:
* If an option is used multiple times, only one command will be sent. If
  the option takes a value, the value of the final appearance of the
  option is used. The only exception is --property, which is additive by
  nature.
* Options --start-exec-queue and --stop-exec-queue are handled together.
  Only one of START_QUEUE/STOP_QUEUE commands will be sent to udevd even
  if both options appear on the command line.

1 files changed, 130 insertions, 61 deletions

diff --git a/src/udev/udevadm-control.c b/src/udev/udevadm-control.c
index 45a71b23f1..68e3249394 100644
--- a/src/udev/udevadm-control.c
+++ b/src/udev/udevadm-control.c
@@ -21,12 +21,25 @@
 
 #include "parse-util.h"
 #include "process-util.h"
+#include "static-destruct.h"
+#include "strv.h"
 #include "syslog-util.h"
 #include "time-util.h"
 #include "udevadm.h"
 #include "udev-ctrl.h"
 #include "virt.h"
 
+static char **arg_env = NULL;
+static usec_t arg_timeout = 60 * USEC_PER_SEC;
+static bool arg_ping = false;
+static bool arg_reload = false;
+static bool arg_exit = false;
+static int arg_max_children = -1;
+static int arg_log_level = -1;
+static int arg_start_exec_queue = -1;
+
+STATIC_DESTRUCTOR_REGISTER(arg_env, strv_freep);
+
 static int help(void) {
         printf("%s control OPTION\n\n"
                "Control the udev daemon.\n\n"
@@ -46,11 +59,7 @@ static int help(void) {
         return 0;
 }
 
-int control_main(int argc, char *argv[], void *userdata) {
-        _cleanup_(udev_ctrl_unrefp) UdevCtrl *uctrl = NULL;
-        usec_t timeout = 60 * USEC_PER_SEC;
-        int c, r;
-
+static int parse_argv(int argc, char *argv[]) {
         enum {
                 ARG_PING = 0x100,
         };
@@ -73,102 +82,78 @@ int control_main(int argc, char *argv[], void *userdata) {
                 {}
         };
 
-        if (running_in_chroot() > 0) {
-                log_info("Running in chroot, ignoring request.");
-                return 0;
-        }
+        int c, r;
+
+        assert(argc >= 0);
+        assert(argv);
 
         if (argc <= 1)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                        "This command expects one or more options.");
 
-        r = udev_ctrl_new(&uctrl);
-        if (r < 0)
-                return log_error_errno(r, "Failed to initialize udev control: %m");
-
         while ((c = getopt_long(argc, argv, "el:sSRp:m:t:Vh", options, NULL)) >= 0)
                 switch (c) {
+
                 case 'e':
-                        r = udev_ctrl_send_exit(uctrl);
-                        if (r == -ENOANO)
-                                log_warning("Cannot specify --exit after --exit, ignoring.");
-                        else if (r < 0)
-                                return log_error_errno(r, "Failed to send exit request: %m");
+                        arg_exit = true;
                         break;
-                case 'l':
-                        r = log_level_from_string(optarg);
-                        if (r < 0)
-                                return log_error_errno(r, "Failed to parse log level '%s': %m", optarg);
 
-                        r = udev_ctrl_send_set_log_level(uctrl, r);
-                        if (r == -ENOANO)
-                                log_warning("Cannot specify --log-level after --exit, ignoring.");
-                        else if (r < 0)
-                                return log_error_errno(r, "Failed to send request to set log level: %m");
+                case 'l':
+                        arg_log_level = log_level_from_string(optarg);
+                        if (arg_log_level < 0)
+                                return log_error_errno(arg_log_level, "Failed to parse log level '%s': %m", optarg);
                         break;
+
                 case 's':
-                        r = udev_ctrl_send_stop_exec_queue(uctrl);
-                        if (r == -ENOANO)
-                                log_warning("Cannot specify --stop-exec-queue after --exit, ignoring.");
-                        else if (r < 0)
-                                return log_error_errno(r, "Failed to send request to stop exec queue: %m");
+                        arg_start_exec_queue = false;
                         break;
+
                 case 'S':
-                        r = udev_ctrl_send_start_exec_queue(uctrl);
-                        if (r == -ENOANO)
-                                log_warning("Cannot specify --start-exec-queue after --exit, ignoring.");
-                        else if (r < 0)
-                                return log_error_errno(r, "Failed to send request to start exec queue: %m");
+                        arg_start_exec_queue = true;
                         break;
+
                 case 'R':
-                        r = udev_ctrl_send_reload(uctrl);
-                        if (r == -ENOANO)
-                                log_warning("Cannot specify --reload after --exit, ignoring.");
-                        else if (r < 0)
-                                return log_error_errno(r, "Failed to send reload request: %m");
+                        arg_reload = true;
                         break;
+
                 case 'p':
                         if (!strchr(optarg, '='))
                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "expect <KEY>=<value> instead of '%s'", optarg);
 
-                        r = udev_ctrl_send_set_env(uctrl, optarg);
-                        if (r == -ENOANO)
-                                log_warning("Cannot specify --property after --exit, ignoring.");
-                        else if (r < 0)
-                                return log_error_errno(r, "Failed to send request to update environment: %m");
+                        r = strv_extend(&arg_env, optarg);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to extend environment: %m");
+
                         break;
+
                 case 'm': {
                         unsigned i;
-
                         r = safe_atou(optarg, &i);
                         if (r < 0)
                                 return log_error_errno(r, "Failed to parse maximum number of children '%s': %m", optarg);
-
-                        r = udev_ctrl_send_set_children_max(uctrl, i);
-                        if (r == -ENOANO)
-                                log_warning("Cannot specify --children-max after --exit, ignoring.");
-                        else if (r < 0)
-                                return log_error_errno(r, "Failed to send request to set number of children: %m");
+                        arg_max_children = i;
                         break;
                 }
+
                 case ARG_PING:
-                        r = udev_ctrl_send_ping(uctrl);
-                        if (r == -ENOANO)
-                                log_error("Cannot specify --ping after --exit, ignoring.");
-                        else if (r < 0)
-                                return log_error_errno(r, "Failed to send a ping message: %m");
+                        arg_ping = true;
                         break;
+
                 case 't':
-                        r = parse_sec(optarg, &timeout);
+                        r = parse_sec(optarg, &arg_timeout);
                         if (r < 0)
                                 return log_error_errno(r, "Failed to parse timeout value '%s': %m", optarg);
                         break;
+
                 case 'V':
                         return print_version();
+
                 case 'h':
                         return help();
+
                 case '?':
                         return -EINVAL;
+
                 default:
                         assert_not_reached();
                 }
@@ -177,7 +162,91 @@ int control_main(int argc, char *argv[], void *userdata) {
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                        "Extraneous argument: %s", argv[optind]);
 
-        r = udev_ctrl_wait(uctrl, timeout);
+        return 1;
+}
+
+int control_main(int argc, char *argv[], void *userdata) {
+        _cleanup_(udev_ctrl_unrefp) UdevCtrl *uctrl = NULL;
+        int r;
+
+        if (running_in_chroot() > 0) {
+                log_info("Running in chroot, ignoring request.");
+                return 0;
+        }
+
+        r = parse_argv(argc, argv);
+        if (r <= 0)
+                return r;
+
+        r = udev_ctrl_new(&uctrl);
+        if (r < 0)
+                return log_error_errno(r, "Failed to initialize udev control: %m");
+
+        if (arg_exit) {
+                r = udev_ctrl_send_exit(uctrl);
+                if (r == -ENOANO)
+                        log_warning("Cannot specify --exit after --exit, ignoring.");
+                else if (r < 0)
+                        return log_error_errno(r, "Failed to send exit request: %m");
+        }
+
+        if (arg_log_level >= 0) {
+                r = udev_ctrl_send_set_log_level(uctrl, r);
+                if (r == -ENOANO)
+                        log_warning("Cannot specify --log-level after --exit, ignoring.");
+                else if (r < 0)
+                        return log_error_errno(r, "Failed to send request to set log level: %m");
+        }
+
+        if (arg_start_exec_queue == false) {
+                r = udev_ctrl_send_stop_exec_queue(uctrl);
+                if (r == -ENOANO)
+                        log_warning("Cannot specify --stop-exec-queue after --exit, ignoring.");
+                else if (r < 0)
+                        return log_error_errno(r, "Failed to send request to stop exec queue: %m");
+        }
+
+        if (arg_start_exec_queue == true) {
+                r = udev_ctrl_send_start_exec_queue(uctrl);
+                if (r == -ENOANO)
+                        log_warning("Cannot specify --start-exec-queue after --exit, ignoring.");
+                else if (r < 0)
+                        return log_error_errno(r, "Failed to send request to start exec queue: %m");
+        }
+
+        if (arg_reload) {
+                r = udev_ctrl_send_reload(uctrl);
+                if (r == -ENOANO)
+                        log_warning("Cannot specify --reload after --exit, ignoring.");
+                else if (r < 0)
+                        return log_error_errno(r, "Failed to send reload request: %m");
+        }
+
+        STRV_FOREACH(env, arg_env) {
+                r = udev_ctrl_send_set_env(uctrl, *env);
+                if (r == -ENOANO)
+                        log_warning("Cannot specify --property after --exit, ignoring.");
+                else if (r < 0)
+                        return log_error_errno(r, "Failed to send request to update environment: %m");
+        }
+
+        if (arg_max_children) {
+                r = udev_ctrl_send_set_children_max(uctrl, arg_max_children);
+                if (r == -ENOANO)
+                        log_warning("Cannot specify --children-max after --exit, ignoring.");
+                else if (r < 0)
+                        return log_error_errno(r, "Failed to send request to set number of children: %m");
+        }
+
+        if (arg_ping) {
+                r = udev_ctrl_send_ping(uctrl);
+                if (r == -ENOANO)
+                        log_error("Cannot specify --ping after --exit, ignoring.");
+                else if (r < 0)
+                        return log_error_errno(r, "Failed to send a ping message: %m");
+        }
+
+        r = udev_ctrl_wait(uctrl, arg_timeout);
         if (r < 0)
                 return log_error_errno(r, "Failed to wait for daemon to reply: %m");