systemd-sleep: add support for freeze and standby

A new config file /etc/systemd/sleep.conf is added.
It is parsed by systemd-sleep and logind. The strings written
to /sys/power/disk and /sys/power/state can be configured.
This allows people to use different modes of suspend on
systems with broken or special hardware.

Configuration is shared between systemd-sleep and logind
to enable logind to answer the question "can the system be
put to sleep" as correctly as possible without actually
invoking the action. If the user configured systemd-sleep
to only use 'freeze', but current kernel does not support it,
logind will properly report that the system cannot be put
to sleep.

https://bugs.freedesktop.org/show_bug.cgi?id=57793
https://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commit;h=7e73c5ae6e7991a6c01f6d096ff8afaef4458c36
http://lists.freedesktop.org/archives/systemd-devel/2013-February/009238.html

SYSTEM_CONFIG_FILE and USER_CONFIG_FILE defines were removed
since they were used in only a few places and with the
addition of /etc/systemd/sleep.conf it becomes easier to just
append the name of each file to the dir name.

1 files changed, 169 insertions, 75 deletions

diff --git a/src/sleep/sleep.c b/src/sleep/sleep.c
index f5e78c13c6..a56ab89e54 100644
--- a/src/sleep/sleep.c
+++ b/src/sleep/sleep.c
@@ -4,6 +4,7 @@
   This file is part of systemd.
 
   Copyright 2012 Lennart Poettering
+  Copyright 2013 Zbigniew Jędrzejewski-Szmek
 
   systemd is free software; you can redistribute it and/or modify it
   under the terms of the GNU Lesser General Public License as published by
@@ -22,107 +23,200 @@
 #include <stdio.h>
 #include <errno.h>
 #include <string.h>
+#include <getopt.h>
 
-#include "log.h"
-#include "util.h"
 #include "systemd/sd-id128.h"
 #include "systemd/sd-messages.h"
+#include "log.h"
+#include "util.h"
+#include "strv.h"
 #include "fileio.h"
+#include "build.h"
+#include "sleep-config.h"
+
+static char* arg_verb = NULL;
+
+static int write_mode(char **modes) {
+        int r = 0;
+        char **mode;
+
+        STRV_FOREACH(mode, modes) {
+                int k = write_string_file("/sys/power/disk", *mode);
+                if (k == 0)
+                        return 0;
+                log_debug("Failed to write '%s' to /sys/power/disk: %s",
+                          *mode, strerror(-k));
+                if (r == 0)
+                        r = k;
+        }
 
-int main(int argc, char *argv[]) {
-        const char *verb;
-        char* arguments[4];
-        int r;
-        FILE *f;
+        if (r < 0)
+                log_error("Failed to write mode to /sys/power/disk: %s",
+                          strerror(-r));
 
-        log_set_target(LOG_TARGET_AUTO);
-        log_parse_environment();
-        log_open();
+        return r;
+}
 
-        if (argc != 2) {
-                log_error("Invalid number of arguments.");
-                r = -EINVAL;
-                goto finish;
+static int write_state(FILE *f0, char **states) {
+        FILE _cleanup_fclose_ *f = f0;
+        char **state;
+        int r = 0;
+
+        STRV_FOREACH(state, states) {
+                int k;
+
+                k = write_string_to_file(f, *state);
+                if (k == 0)
+                        return 0;
+                log_debug("Failed to write '%s' to /sys/power/state: %s",
+                          *state, strerror(-k));
+                if (r == 0)
+                        r = k;
+
+                fclose(f);
+                f = fopen("/sys/power/state", "we");
+                if (!f) {
+                        log_error("Failed to open /sys/power/state: %m");
+                        return -errno;
+                }
         }
 
-        if (streq(argv[1], "suspend"))
-                verb = "mem";
-        else if (streq(argv[1], "hibernate") || streq(argv[1], "hybrid-sleep"))
-                verb = "disk";
-        else {
-                log_error("Unknown action '%s'.", argv[1]);
-                r = -EINVAL;
-                goto finish;
-        }
+        return r;
+}
 
-        /* Configure the hibernation mode */
-        if (streq(argv[1], "hibernate")) {
-                if (write_string_file("/sys/power/disk", "platform") < 0)
-                        write_string_file("/sys/power/disk", "shutdown");
-        } else if (streq(argv[1], "hybrid-sleep")) {
-                if (write_string_file("/sys/power/disk", "suspend") < 0)
-                        if (write_string_file("/sys/power/disk", "platform") < 0)
-                                write_string_file("/sys/power/disk", "shutdown");
-        }
+static int execute(char **modes, char **states) {
+        char* arguments[4];
+        int r;
+        FILE *f;
+        const char* note = strappenda("SLEEP=", arg_verb);
 
+        /* This file is opened first, so that if we hit an error,
+         * we can abort before modyfing any state. */
         f = fopen("/sys/power/state", "we");
         if (!f) {
                 log_error("Failed to open /sys/power/state: %m");
-                r = -errno;
-                goto finish;
+                return -errno;
         }
 
+        /* Configure the hibernation mode */
+        r = write_mode(modes);
+        if (r < 0)
+                return r;
+
         arguments[0] = NULL;
         arguments[1] = (char*) "pre";
-        arguments[2] = argv[1];
+        arguments[2] = arg_verb;
         arguments[3] = NULL;
         execute_directory(SYSTEM_SLEEP_PATH, NULL, arguments);
 
-        if (streq(argv[1], "suspend"))
-                log_struct(LOG_INFO,
-                           MESSAGE_ID(SD_MESSAGE_SLEEP_START),
-                           "MESSAGE=Suspending system...",
-                           "SLEEP=suspend",
-                           NULL);
-        else if (streq(argv[1], "hibernate"))
-                log_struct(LOG_INFO,
-                           MESSAGE_ID(SD_MESSAGE_SLEEP_START),
-                           "MESSAGE=Hibernating system...",
-                           "SLEEP=hibernate",
-                           NULL);
-        else
-                log_struct(LOG_INFO,
-                           MESSAGE_ID(SD_MESSAGE_SLEEP_START),
-                           "MESSAGE=Hibernating and suspending system...",
-                           "SLEEP=hybrid-sleep",
-                           NULL);
-
-        fputs(verb, f);
-        fputc('\n', f);
-        fflush(f);
-
-        r = ferror(f) ? -errno : 0;
-
-        if (streq(argv[1], "suspend"))
-                log_struct(LOG_INFO,
-                           MESSAGE_ID(SD_MESSAGE_SLEEP_STOP),
-                           "MESSAGE=System resumed.",
-                           "SLEEP=suspend",
-                           NULL);
-        else
-                log_struct(LOG_INFO,
-                           MESSAGE_ID(SD_MESSAGE_SLEEP_STOP),
-                           "MESSAGE=System thawed.",
-                           "SLEEP=hibernate",
-                           NULL);
+        log_struct(LOG_INFO,
+                   MESSAGE_ID(SD_MESSAGE_SLEEP_START),
+                   "MESSAGE=Suspending system...",
+                   note,
+                   NULL);
+
+        r = write_state(f, states);
+        if (r < 0)
+                return r;
+
+        log_struct(LOG_INFO,
+                   MESSAGE_ID(SD_MESSAGE_SLEEP_STOP),
+                   "MESSAGE=System resumed.",
+                   note,
+                   NULL);
 
         arguments[1] = (char*) "post";
         execute_directory(SYSTEM_SLEEP_PATH, NULL, arguments);
 
-        fclose(f);
+        return r;
+}
 
-finish:
+static int help(void) {
+        printf("%s COMMAND\n\n"
+               "Suspend the system, hibernate the system, or both.\n\n"
+               "Commands:\n"
+               "  -h --help            Show this help and exit\n"
+               "  --version            Print version string and exit\n"
+               "  suspend              Suspend the system\n"
+               "  hibernate            Hibernate the system\n"
+               "  hybrid-sleep         Both hibernate and suspend the system\n"
+               , program_invocation_short_name
+               );
+
+        return 0;
+}
 
-        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+static int parse_argv(int argc, char *argv[]) {
+        enum {
+                ARG_VERSION = 0x100,
+        };
+
+        static const struct option options[] = {
+                { "help",         no_argument,       NULL, 'h'           },
+                { "version",      no_argument,       NULL, ARG_VERSION   },
+                { NULL,           0,                 NULL, 0             }
+        };
+
+        int c;
+
+        assert(argc >= 0);
+        assert(argv);
+
+        while ((c = getopt_long(argc, argv, "+h", options, NULL)) >= 0)
+                switch(c) {
+                case 'h':
+                        help();
+                        return 0 /* done */;
+
+                case ARG_VERSION:
+                        puts(PACKAGE_STRING);
+                        puts(SYSTEMD_FEATURES);
+                        return 0 /* done */;
+
+                case '?':
+                        return -EINVAL;
+
+                default:
+                        log_error("Unknown option code %c", c);
+                        return -EINVAL;
+                }
+
+        if (argc - optind != 1) {
+                log_error("Usage: %s COMMAND",
+                          program_invocation_short_name);
+                return -EINVAL;
+        }
+
+        arg_verb = argv[optind];
 
+        if (!streq(arg_verb, "suspend") &&
+            !streq(arg_verb, "hibernate") &&
+            !streq(arg_verb, "hybrid-sleep")) {
+                log_error("Unknown command '%s'.", arg_verb);
+                return -EINVAL;
+        }
+
+        return 1 /* work to do */;
+}
+
+int main(int argc, char *argv[]) {
+        _cleanup_strv_free_ char **modes = NULL, **states = NULL;
+        int r;
+
+        log_set_target(LOG_TARGET_AUTO);
+        log_parse_environment();
+        log_open();
+
+        r = parse_argv(argc, argv);
+        if (r <= 0)
+                goto finish;
+
+        r = parse_sleep_config(arg_verb, &modes, &states);
+        if (r < 0)
+                goto finish;
+
+        r = execute(modes, states);
+
+finish:
+        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 }