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, 182 insertions, 0 deletions

diff --git a/src/shared/sleep-config.c b/src/shared/sleep-config.c
new file mode 100644
index 0000000000..73a3acb8be
--- /dev/null
+++ b/src/shared/sleep-config.c
@@ -0,0 +1,182 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  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
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+
+#include "conf-parser.h"
+#include "sleep-config.h"
+#include "fileio.h"
+#include "log.h"
+#include "strv.h"
+#include "util.h"
+
+int parse_sleep_config(const char *verb, char ***modes, char ***states) {
+        _cleanup_strv_free_ char
+                **suspend_mode = NULL, **suspend_state = NULL,
+                **hibernate_mode = NULL, **hibernate_state = NULL,
+                **hybrid_mode = NULL, **hybrid_state = NULL;
+
+        const ConfigTableItem items[] = {
+                { "Sleep",   "SuspendMode",      config_parse_strv,  0, &suspend_mode  },
+                { "Sleep",   "SuspendState",     config_parse_strv,  0, &suspend_state },
+                { "Sleep",   "HibernateMode",    config_parse_strv,  0, &hibernate_mode  },
+                { "Sleep",   "HibernateState",   config_parse_strv,  0, &hibernate_state },
+                { "Sleep",   "HybridSleepMode",  config_parse_strv,  0, &hybrid_mode  },
+                { "Sleep",   "HybridSleepState", config_parse_strv,  0, &hybrid_state },
+                {}};
+
+        int r;
+        FILE _cleanup_fclose_ *f;
+
+        f = fopen(PKGSYSCONFDIR "/sleep.conf", "re");
+        if (!f) {
+                if (errno == ENOENT)
+                        return 0;
+
+                log_warning("Failed to open configuration file " PKGSYSCONFDIR "/sleep.conf: %m");
+                return 0;
+        }
+
+        r = config_parse(NULL, PKGSYSCONFDIR "/sleep.conf", f, "Sleep\0",
+                         config_item_table_lookup, (void*) items, false, false, NULL);
+        if (r < 0)
+                log_warning("Failed to parse configuration file: %s", strerror(-r));
+
+        if (streq(verb, "suspend")) {
+                /* empty by default */
+                *modes = suspend_mode;
+
+                if (suspend_state)
+                        *states = suspend_state;
+                else
+                        *states = strv_split_nulstr("mem\0standby\0freeze\0");
+
+                suspend_mode = suspend_state = NULL;
+        } else if (streq(verb, "hibernate")) {
+                if (hibernate_mode)
+                        *modes = hibernate_mode;
+                else
+                        *modes = strv_split_nulstr("platform\0shutdown\0");
+
+                if (hibernate_state)
+                        *states = hibernate_state;
+                else
+                        *states = strv_split_nulstr("disk\0");
+
+                hibernate_mode = hibernate_state = NULL;
+        } else if (streq(verb, "hybrid-sleep")) {
+                if (hybrid_mode)
+                        *modes = hybrid_mode;
+                else
+                        *modes = strv_split_nulstr("suspend\0platform\0shutdown\0");
+
+                if (hybrid_state)
+                        *states = hybrid_state;
+                else
+                        *states = strv_split_nulstr("disk\0");
+
+                hybrid_mode = hybrid_state = NULL;
+        } else
+                assert_not_reached("what verb");
+
+        if (!modes || !states) {
+                strv_free(*modes);
+                strv_free(*states);
+                return log_oom();
+        }
+
+        return 0;
+}
+
+int can_sleep_state(char **types) {
+        char *w, *state, **type;
+        int r;
+        _cleanup_free_ char *p = NULL;
+
+        if (strv_isempty(types))
+                return true;
+
+        /* If /sys is read-only we cannot sleep */
+        if (access("/sys/power/state", W_OK) < 0)
+                return false;
+
+        r = read_one_line_file("/sys/power/state", &p);
+        if (r < 0)
+                return false;
+
+        STRV_FOREACH(type, types) {
+                size_t l, k;
+
+                k = strlen(*type);
+                FOREACH_WORD_SEPARATOR(w, l, p, WHITESPACE, state)
+                        if (l == k && memcmp(w, *type, l) == 0)
+                                return true;
+        }
+
+        return false;
+}
+
+int can_sleep_disk(char **types) {
+        char *w, *state, **type;
+        int r;
+        _cleanup_free_ char *p = NULL;
+
+        if (strv_isempty(types))
+                return true;
+
+        /* If /sys is read-only we cannot sleep */
+        if (access("/sys/power/disk", W_OK) < 0)
+                return false;
+
+        r = read_one_line_file("/sys/power/disk", &p);
+        if (r < 0)
+                return false;
+
+        STRV_FOREACH(type, types) {
+                size_t l, k;
+
+                k = strlen(*type);
+                FOREACH_WORD_SEPARATOR(w, l, p, WHITESPACE, state) {
+                        if (l == k && memcmp(w, *type, l) == 0)
+                                return true;
+
+                        if (l == k + 2 && w[0] == '[' && memcmp(w + 1, *type, l - 2) == 0 && w[l-1] == ']')
+                                return true;
+                }
+        }
+
+        return false;
+}
+
+int can_sleep(const char *verb) {
+        _cleanup_strv_free_ char **modes = NULL, **states = NULL;
+        int r;
+
+        assert(streq(verb, "suspend") ||
+               streq(verb, "hibernate") ||
+               streq(verb, "hybrid-sleep"));
+
+        r = parse_sleep_config(verb, &modes, &states);
+        if (r < 0)
+                return false;
+
+        return can_sleep_state(states) && can_sleep_disk(modes);
+}