Adding upstream version 247.3.upstream/247.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 703 insertions, 0 deletions

diff --git a/src/shared/sleep-config.c b/src/shared/sleep-config.c
new file mode 100644
index 0000000..cea5148
--- /dev/null
+++ b/src/shared/sleep-config.c
@@ -0,0 +1,703 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/***
+  Copyright © 2018 Dell Inc.
+***/
+
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/fs.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <syslog.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "blockdev-util.h"
+#include "btrfs-util.h"
+#include "conf-parser.h"
+#include "def.h"
+#include "env-util.h"
+#include "errno-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "log.h"
+#include "macro.h"
+#include "parse-util.h"
+#include "path-util.h"
+#include "sleep-config.h"
+#include "stdio-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "time-util.h"
+
+int parse_sleep_config(SleepConfig **ret_sleep_config) {
+        _cleanup_(free_sleep_configp) SleepConfig *sc;
+        int allow_suspend = -1, allow_hibernate = -1,
+            allow_s2h = -1, allow_hybrid_sleep = -1;
+
+        sc = new0(SleepConfig, 1);
+        if (!sc)
+                return log_oom();
+
+        const ConfigTableItem items[] = {
+                { "Sleep", "AllowSuspend",              config_parse_tristate, 0, &allow_suspend },
+                { "Sleep", "AllowHibernation",          config_parse_tristate, 0, &allow_hibernate },
+                { "Sleep", "AllowSuspendThenHibernate", config_parse_tristate, 0, &allow_s2h },
+                { "Sleep", "AllowHybridSleep",          config_parse_tristate, 0, &allow_hybrid_sleep },
+
+                { "Sleep", "SuspendMode",               config_parse_strv, 0, &sc->suspend_modes  },
+                { "Sleep", "SuspendState",              config_parse_strv, 0, &sc->suspend_states },
+                { "Sleep", "HibernateMode",             config_parse_strv, 0, &sc->hibernate_modes  },
+                { "Sleep", "HibernateState",            config_parse_strv, 0, &sc->hibernate_states },
+                { "Sleep", "HybridSleepMode",           config_parse_strv, 0, &sc->hybrid_modes  },
+                { "Sleep", "HybridSleepState",          config_parse_strv, 0, &sc->hybrid_states },
+
+                { "Sleep", "HibernateDelaySec",         config_parse_sec,  0, &sc->hibernate_delay_sec},
+                {}
+        };
+
+        (void) config_parse_many_nulstr(
+                        PKGSYSCONFDIR "/sleep.conf",
+                        CONF_PATHS_NULSTR("systemd/sleep.conf.d"),
+                        "Sleep\0",
+                        config_item_table_lookup, items,
+                        CONFIG_PARSE_WARN,
+                        NULL,
+                        NULL);
+
+        /* use default values unless set */
+        sc->allow_suspend = allow_suspend != 0;
+        sc->allow_hibernate = allow_hibernate != 0;
+        sc->allow_hybrid_sleep = allow_hybrid_sleep >= 0 ? allow_hybrid_sleep
+                : (allow_suspend != 0 && allow_hibernate != 0);
+        sc->allow_s2h = allow_s2h >= 0 ? allow_s2h
+                : (allow_suspend != 0 && allow_hibernate != 0);
+
+        if (!sc->suspend_states)
+                sc->suspend_states = strv_new("mem", "standby", "freeze");
+        if (!sc->hibernate_modes)
+                sc->hibernate_modes = strv_new("platform", "shutdown");
+        if (!sc->hibernate_states)
+                sc->hibernate_states = strv_new("disk");
+        if (!sc->hybrid_modes)
+                sc->hybrid_modes = strv_new("suspend", "platform", "shutdown");
+        if (!sc->hybrid_states)
+                sc->hybrid_states = strv_new("disk");
+        if (sc->hibernate_delay_sec == 0)
+                sc->hibernate_delay_sec = 2 * USEC_PER_HOUR;
+
+        /* ensure values set for all required fields */
+        if (!sc->suspend_states || !sc->hibernate_modes
+            || !sc->hibernate_states || !sc->hybrid_modes || !sc->hybrid_states)
+                return log_oom();
+
+        *ret_sleep_config = TAKE_PTR(sc);
+
+        return 0;
+}
+
+int can_sleep_state(char **types) {
+        _cleanup_free_ char *text = NULL;
+        int r;
+
+        if (strv_isempty(types))
+                return true;
+
+        /* If /sys is read-only we cannot sleep */
+        if (access("/sys/power/state", W_OK) < 0) {
+                log_debug_errno(errno, "/sys/power/state is not writable, cannot sleep: %m");
+                return false;
+        }
+
+        r = read_one_line_file("/sys/power/state", &text);
+        if (r < 0) {
+                log_debug_errno(r, "Failed to read /sys/power/state, cannot sleep: %m");
+                return false;
+        }
+
+        const char *found;
+        r = string_contains_word_strv(text, NULL, types, &found);
+        if (r < 0)
+                return log_debug_errno(r, "Failed to parse /sys/power/state: %m");
+        if (r > 0)
+                log_debug("Sleep mode \"%s\" is supported by the kernel.", found);
+        else if (DEBUG_LOGGING) {
+                _cleanup_free_ char *t = strv_join(types, "/");
+                log_debug("Sleep mode %s not supported by the kernel, sorry.", strnull(t));
+        }
+        return r;
+}
+
+int can_sleep_disk(char **types) {
+        _cleanup_free_ char *text = NULL;
+        int r;
+
+        if (strv_isempty(types))
+                return true;
+
+        /* If /sys is read-only we cannot sleep */
+        if (access("/sys/power/disk", W_OK) < 0) {
+                log_debug_errno(errno, "/sys/power/disk is not writable: %m");
+                return false;
+        }
+
+        r = read_one_line_file("/sys/power/disk", &text);
+        if (r < 0) {
+                log_debug_errno(r, "Couldn't read /sys/power/disk: %m");
+                return false;
+        }
+
+        for (const char *p = text;;) {
+                _cleanup_free_ char *word = NULL;
+
+                r = extract_first_word(&p, &word, NULL, 0);
+                if (r < 0)
+                        return log_debug_errno(r, "Failed to parse /sys/power/disk: %m");
+                if (r == 0)
+                        break;
+
+                char *s = word;
+                size_t l = strlen(s);
+                if (s[0] == '[' && s[l-1] == ']') {
+                        s[l-1] = '\0';
+                        s++;
+                }
+
+                if (strv_contains(types, s)) {
+                        log_debug("Disk sleep mode \"%s\" is supported by the kernel.", s);
+                        return true;
+                }
+        }
+
+        if (DEBUG_LOGGING) {
+                _cleanup_free_ char *t = strv_join(types, "/");
+                log_debug("Disk sleep mode %s not supported by the kernel, sorry.", strnull(t));
+        }
+        return false;
+}
+
+#define HIBERNATION_SWAP_THRESHOLD 0.98
+
+SwapEntry* swap_entry_free(SwapEntry *se) {
+        if (!se)
+                return NULL;
+
+        free(se->device);
+        free(se->type);
+
+        return mfree(se);
+}
+
+HibernateLocation* hibernate_location_free(HibernateLocation *hl) {
+        if (!hl)
+                return NULL;
+
+        swap_entry_free(hl->swap);
+
+        return mfree(hl);
+}
+
+static int swap_device_to_device_id(const SwapEntry *swap, dev_t *ret_dev) {
+        struct stat sb;
+        int r;
+
+        assert(swap);
+        assert(swap->device);
+        assert(swap->type);
+
+        r = stat(swap->device, &sb);
+        if (r < 0)
+                return -errno;
+
+        if (streq(swap->type, "partition")) {
+                if (!S_ISBLK(sb.st_mode))
+                        return -ENOTBLK;
+
+                *ret_dev = sb.st_rdev;
+                return 0;
+        }
+
+        return get_block_device(swap->device, ret_dev);
+}
+
+/*
+ * Attempt to calculate the swap file offset on supported filesystems. On unsupported
+ * filesystems, a debug message is logged and ret_offset is set to UINT64_MAX.
+ */
+static int calculate_swap_file_offset(const SwapEntry *swap, uint64_t *ret_offset) {
+        _cleanup_close_ int fd = -1;
+        _cleanup_free_ struct fiemap *fiemap = NULL;
+        struct stat sb;
+        int r, btrfs;
+
+        assert(swap);
+        assert(swap->device);
+        assert(streq(swap->type, "file"));
+
+        fd = open(swap->device, O_RDONLY|O_CLOEXEC|O_NOCTTY);
+        if (fd < 0)
+                return log_debug_errno(errno, "Failed to open swap file %s to determine on-disk offset: %m", swap->device);
+
+        if (fstat(fd, &sb) < 0)
+                return log_debug_errno(errno, "Failed to stat %s: %m", swap->device);
+
+        btrfs = btrfs_is_filesystem(fd);
+        if (btrfs < 0)
+                return log_debug_errno(btrfs, "Error checking %s for Btrfs filesystem: %m", swap->device);
+        if (btrfs > 0) {
+                log_debug("%s: detection of swap file offset on Btrfs is not supported", swap->device);
+                *ret_offset = UINT64_MAX;
+                return 0;
+        }
+
+        r = read_fiemap(fd, &fiemap);
+        if (r < 0)
+                return log_debug_errno(r, "Unable to read extent map for '%s': %m", swap->device);
+
+        *ret_offset = fiemap->fm_extents[0].fe_physical / page_size();
+        return 0;
+}
+
+static int read_resume_files(dev_t *ret_resume, uint64_t *ret_resume_offset) {
+        _cleanup_free_ char *resume_str = NULL, *resume_offset_str = NULL;
+        uint64_t resume_offset = 0;
+        dev_t resume;
+        int r;
+
+        r = read_one_line_file("/sys/power/resume", &resume_str);
+        if (r < 0)
+                return log_debug_errno(r, "Error reading /sys/power/resume: %m");
+
+        r = parse_dev(resume_str, &resume);
+        if (r < 0)
+                return log_debug_errno(r, "Error parsing /sys/power/resume device: %s: %m", resume_str);
+
+        r = read_one_line_file("/sys/power/resume_offset", &resume_offset_str);
+        if (r == -ENOENT)
+                log_debug_errno(r, "Kernel does not support resume_offset; swap file offset detection will be skipped.");
+        else if (r < 0)
+                return log_debug_errno(r, "Error reading /sys/power/resume_offset: %m");
+        else {
+                r = safe_atou64(resume_offset_str, &resume_offset);
+                if (r < 0)
+                        return log_debug_errno(r, "Failed to parse value in /sys/power/resume_offset \"%s\": %m", resume_offset_str);
+        }
+
+        if (resume_offset > 0 && resume == 0)
+                log_debug("Warning: found /sys/power/resume_offset==%" PRIu64 ", but /sys/power/resume unset. Misconfiguration?",
+                          resume_offset);
+
+        *ret_resume = resume;
+        *ret_resume_offset = resume_offset;
+
+        return 0;
+}
+
+/*
+ * Determine if the HibernateLocation matches the resume= (device) and resume_offset= (file).
+ */
+static bool location_is_resume_device(const HibernateLocation *location, dev_t sys_resume, uint64_t sys_offset) {
+        if (!location)
+                return false;
+
+        return  sys_resume > 0 &&
+                sys_resume == location->devno &&
+                (sys_offset == location->offset || (sys_offset > 0 && location->offset == UINT64_MAX));
+}
+
+/*
+ * Attempt to find the hibernation location by parsing /proc/swaps, /sys/power/resume, and
+ * /sys/power/resume_offset.
+ *
+ * Returns:
+ *  1 - Values are set in /sys/power/resume and /sys/power/resume_offset.
+ *      ret_hibernate_location will represent matching /proc/swap entry if identified or NULL if not.
+ *
+ *  0 - No values are set in /sys/power/resume and /sys/power/resume_offset.
+        ret_hibernate_location will represent the highest priority swap with most remaining space discovered in /proc/swaps.
+ *
+ *  Negative value in the case of error.
+ */
+int find_hibernate_location(HibernateLocation **ret_hibernate_location) {
+        _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_(hibernate_location_freep) HibernateLocation *hibernate_location = NULL;
+        dev_t sys_resume;
+        uint64_t sys_offset = 0;
+        bool resume_match = false;
+        int r;
+
+        /* read the /sys/power/resume & /sys/power/resume_offset values */
+        r = read_resume_files(&sys_resume, &sys_offset);
+        if (r < 0)
+                return r;
+
+        f = fopen("/proc/swaps", "re");
+        if (!f) {
+                log_debug_errno(errno, "Failed to open /proc/swaps: %m");
+                return errno == ENOENT ? -EOPNOTSUPP : -errno; /* Convert swap not supported to a recognizable error */
+        }
+
+        (void) fscanf(f, "%*s %*s %*s %*s %*s\n");
+        for (unsigned i = 1;; i++) {
+                _cleanup_(swap_entry_freep) SwapEntry *swap = NULL;
+                uint64_t swap_offset = 0;
+                int k;
+
+                swap = new0(SwapEntry, 1);
+                if (!swap)
+                        return -ENOMEM;
+
+                k = fscanf(f,
+                           "%ms "       /* device/file */
+                           "%ms "       /* type of swap */
+                           "%" PRIu64   /* swap size */
+                           "%" PRIu64   /* used */
+                           "%i\n",      /* priority */
+                           &swap->device, &swap->type, &swap->size, &swap->used, &swap->priority);
+                if (k == EOF)
+                        break;
+                if (k != 5) {
+                        log_debug("Failed to parse /proc/swaps:%u, ignoring", i);
+                        continue;
+                }
+
+                if (streq(swap->type, "file")) {
+                        if (endswith(swap->device, "\\040(deleted)")) {
+                                log_debug("Ignoring deleted swap file '%s'.", swap->device);
+                                continue;
+                        }
+
+                        r = calculate_swap_file_offset(swap, &swap_offset);
+                        if (r < 0)
+                                return r;
+
+                } else if (streq(swap->type, "partition")) {
+                        const char *fn;
+
+                        fn = path_startswith(swap->device, "/dev/");
+                        if (fn && startswith(fn, "zram")) {
+                                log_debug("%s: ignoring zram swap", swap->device);
+                                continue;
+                        }
+
+                } else {
+                        log_debug("%s: swap type %s is unsupported for hibernation, ignoring", swap->device, swap->type);
+                        continue;
+                }
+
+                /* prefer resume device or highest priority swap with most remaining space */
+                if (hibernate_location && swap->priority < hibernate_location->swap->priority) {
+                        log_debug("%s: ignoring device with lower priority", swap->device);
+                        continue;
+                }
+                if (hibernate_location &&
+                    (swap->priority == hibernate_location->swap->priority
+                     && swap->size - swap->used < hibernate_location->swap->size - hibernate_location->swap->used)) {
+                        log_debug("%s: ignoring device with lower usable space", swap->device);
+                        continue;
+                }
+
+                dev_t swap_device;
+                r = swap_device_to_device_id(swap, &swap_device);
+                if (r < 0)
+                        return log_debug_errno(r, "%s: failed to query device number: %m", swap->device);
+                if (swap_device == 0)
+                        return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "%s: not backed by block device.", swap->device);
+
+                hibernate_location = hibernate_location_free(hibernate_location);
+                hibernate_location = new(HibernateLocation, 1);
+                if (!hibernate_location)
+                        return -ENOMEM;
+
+                *hibernate_location = (HibernateLocation) {
+                        .devno = swap_device,
+                        .offset = swap_offset,
+                        .swap = TAKE_PTR(swap),
+                };
+
+                /* if the swap is the resume device, stop the loop */
+                if (location_is_resume_device(hibernate_location, sys_resume, sys_offset)) {
+                        log_debug("%s: device matches configured resume settings.", hibernate_location->swap->device);
+                        resume_match = true;
+                        break;
+                }
+
+                log_debug("%s: is a candidate device.", hibernate_location->swap->device);
+        }
+
+        /* We found nothing at all */
+        if (!hibernate_location)
+                return log_debug_errno(SYNTHETIC_ERRNO(ENOSYS),
+                                       "No possible swap partitions or files suitable for hibernation were found in /proc/swaps.");
+
+        /* resume= is set but a matching /proc/swaps entry was not found */
+        if (sys_resume != 0 && !resume_match)
+                return log_debug_errno(SYNTHETIC_ERRNO(ENOSYS),
+                                       "No swap partitions or files matching resume config were found in /proc/swaps.");
+
+        if (hibernate_location->offset == UINT64_MAX) {
+                if (sys_offset == 0)
+                        return log_debug_errno(SYNTHETIC_ERRNO(ENOSYS), "Offset detection failed and /sys/power/resume_offset is not set.");
+
+                hibernate_location->offset = sys_offset;
+        }
+
+        if (resume_match)
+                log_debug("Hibernation will attempt to use swap entry with path: %s, device: %u:%u, offset: %" PRIu64 ", priority: %i",
+                          hibernate_location->swap->device, major(hibernate_location->devno), minor(hibernate_location->devno),
+                          hibernate_location->offset, hibernate_location->swap->priority);
+        else
+                log_debug("/sys/power/resume is not configured; attempting to hibernate with path: %s, device: %u:%u, offset: %" PRIu64 ", priority: %i",
+                          hibernate_location->swap->device, major(hibernate_location->devno), minor(hibernate_location->devno),
+                          hibernate_location->offset, hibernate_location->swap->priority);
+
+        *ret_hibernate_location = TAKE_PTR(hibernate_location);
+
+        if (resume_match)
+                return 1;
+
+        return 0;
+}
+
+static bool enough_swap_for_hibernation(void) {
+        _cleanup_free_ char *active = NULL;
+        _cleanup_(hibernate_location_freep) HibernateLocation *hibernate_location = NULL;
+        unsigned long long act = 0;
+        int r;
+
+        if (getenv_bool("SYSTEMD_BYPASS_HIBERNATION_MEMORY_CHECK") > 0)
+                return true;
+
+        r = find_hibernate_location(&hibernate_location);
+        if (r < 0)
+                return false;
+
+        /* If /sys/power/{resume,resume_offset} is configured but a matching entry
+         * could not be identified in /proc/swaps, user is likely using Btrfs with a swapfile;
+         * return true and let the system attempt hibernation.
+         */
+        if (r > 0 && !hibernate_location) {
+                log_debug("Unable to determine remaining swap space; hibernation may fail");
+                return true;
+        }
+
+        if (!hibernate_location)
+                return false;
+
+        r = get_proc_field("/proc/meminfo", "Active(anon)", WHITESPACE, &active);
+        if (r < 0) {
+                log_debug_errno(r, "Failed to retrieve Active(anon) from /proc/meminfo: %m");
+                return false;
+        }
+
+        r = safe_atollu(active, &act);
+        if (r < 0) {
+                log_debug_errno(r, "Failed to parse Active(anon) from /proc/meminfo: %s: %m", active);
+                return false;
+        }
+
+        r = act <= (hibernate_location->swap->size - hibernate_location->swap->used) * HIBERNATION_SWAP_THRESHOLD;
+        log_debug("%s swap for hibernation, Active(anon)=%llu kB, size=%" PRIu64 " kB, used=%" PRIu64 " kB, threshold=%.2g%%",
+                  r ? "Enough" : "Not enough", act, hibernate_location->swap->size, hibernate_location->swap->used, 100*HIBERNATION_SWAP_THRESHOLD);
+
+        return r;
+}
+
+int read_fiemap(int fd, struct fiemap **ret) {
+        _cleanup_free_ struct fiemap *fiemap = NULL, *result_fiemap = NULL;
+        struct stat statinfo;
+        uint32_t result_extents = 0;
+        uint64_t fiemap_start = 0, fiemap_length;
+        const size_t n_extra = DIV_ROUND_UP(sizeof(struct fiemap), sizeof(struct fiemap_extent));
+        size_t fiemap_allocated = n_extra, result_fiemap_allocated = n_extra;
+
+        if (fstat(fd, &statinfo) < 0)
+                return log_debug_errno(errno, "Cannot determine file size: %m");
+        if (!S_ISREG(statinfo.st_mode))
+                return -ENOTTY;
+        fiemap_length = statinfo.st_size;
+
+        /* Zero this out in case we run on a file with no extents */
+        fiemap = calloc(n_extra, sizeof(struct fiemap_extent));
+        if (!fiemap)
+                return -ENOMEM;
+
+        result_fiemap = malloc_multiply(n_extra, sizeof(struct fiemap_extent));
+        if (!result_fiemap)
+                return -ENOMEM;
+
+        /*  XFS filesystem has incorrect implementation of fiemap ioctl and
+         *  returns extents for only one block-group at a time, so we need
+         *  to handle it manually, starting the next fiemap call from the end
+         *  of the last extent
+         */
+        while (fiemap_start < fiemap_length) {
+                *fiemap = (struct fiemap) {
+                        .fm_start = fiemap_start,
+                        .fm_length = fiemap_length,
+                        .fm_flags = FIEMAP_FLAG_SYNC,
+                };
+
+                /* Find out how many extents there are */
+                if (ioctl(fd, FS_IOC_FIEMAP, fiemap) < 0)
+                        return log_debug_errno(errno, "Failed to read extents: %m");
+
+                /* Nothing to process */
+                if (fiemap->fm_mapped_extents == 0)
+                        break;
+
+                /* Resize fiemap to allow us to read in the extents, result fiemap has to hold all
+                 * the extents for the whole file. Add space for the initial struct fiemap. */
+                if (!greedy_realloc0((void**) &fiemap, &fiemap_allocated,
+                                     n_extra + fiemap->fm_mapped_extents, sizeof(struct fiemap_extent)))
+                        return -ENOMEM;
+
+                fiemap->fm_extent_count = fiemap->fm_mapped_extents;
+                fiemap->fm_mapped_extents = 0;
+
+                if (ioctl(fd, FS_IOC_FIEMAP, fiemap) < 0)
+                        return log_debug_errno(errno, "Failed to read extents: %m");
+
+                /* Resize result_fiemap to allow us to copy in the extents */
+                if (!greedy_realloc((void**) &result_fiemap, &result_fiemap_allocated,
+                                    n_extra + result_extents + fiemap->fm_mapped_extents, sizeof(struct fiemap_extent)))
+                        return -ENOMEM;
+
+                memcpy(result_fiemap->fm_extents + result_extents,
+                       fiemap->fm_extents,
+                       sizeof(struct fiemap_extent) * fiemap->fm_mapped_extents);
+
+                result_extents += fiemap->fm_mapped_extents;
+
+                /* Highly unlikely that it is zero */
+                if (_likely_(fiemap->fm_mapped_extents > 0)) {
+                        uint32_t i = fiemap->fm_mapped_extents - 1;
+
+                        fiemap_start = fiemap->fm_extents[i].fe_logical +
+                                       fiemap->fm_extents[i].fe_length;
+
+                        if (fiemap->fm_extents[i].fe_flags & FIEMAP_EXTENT_LAST)
+                                break;
+                }
+        }
+
+        memcpy(result_fiemap, fiemap, sizeof(struct fiemap));
+        result_fiemap->fm_mapped_extents = result_extents;
+        *ret = TAKE_PTR(result_fiemap);
+        return 0;
+}
+
+static int can_sleep_internal(const char *verb, bool check_allowed, const SleepConfig *sleep_config);
+
+static bool can_s2h(const SleepConfig *sleep_config) {
+        const char *p;
+        int r;
+
+        if (!clock_supported(CLOCK_BOOTTIME_ALARM)) {
+                log_debug("CLOCK_BOOTTIME_ALARM is not supported.");
+                return false;
+        }
+
+        FOREACH_STRING(p, "suspend", "hibernate") {
+                r = can_sleep_internal(p, false, sleep_config);
+                if (IN_SET(r, 0, -ENOSPC, -EADV)) {
+                        log_debug("Unable to %s system.", p);
+                        return false;
+                }
+                if (r < 0)
+                        return log_debug_errno(r, "Failed to check if %s is possible: %m", p);
+        }
+
+        return true;
+}
+
+static int can_sleep_internal(const char *verb, bool check_allowed, const SleepConfig *sleep_config) {
+        bool allow;
+        char **modes = NULL, **states = NULL;
+        int r;
+
+        assert(STR_IN_SET(verb, "suspend", "hibernate", "hybrid-sleep", "suspend-then-hibernate"));
+
+        r = sleep_settings(verb, sleep_config, &allow, &modes, &states);
+        if (r < 0)
+                return false;
+
+        if (check_allowed && !allow) {
+                log_debug("Sleep mode \"%s\" is disabled by configuration.", verb);
+                return false;
+        }
+
+        if (streq(verb, "suspend-then-hibernate"))
+                return can_s2h(sleep_config);
+
+        if (!can_sleep_state(states) || !can_sleep_disk(modes))
+                return false;
+
+        if (streq(verb, "suspend"))
+                return true;
+
+        if (!enough_swap_for_hibernation())
+                return -ENOSPC;
+
+        return true;
+}
+
+int can_sleep(const char *verb) {
+        _cleanup_(free_sleep_configp) SleepConfig *sleep_config = NULL;
+        int r;
+
+        r = parse_sleep_config(&sleep_config);
+        if (r < 0)
+                return r;
+
+        return can_sleep_internal(verb, true, sleep_config);
+}
+
+int sleep_settings(const char *verb, const SleepConfig *sleep_config, bool *ret_allow, char ***ret_modes, char ***ret_states) {
+
+        assert(verb);
+        assert(sleep_config);
+        assert(STR_IN_SET(verb, "suspend", "hibernate", "hybrid-sleep", "suspend-then-hibernate"));
+
+        if (streq(verb, "suspend")) {
+                *ret_allow = sleep_config->allow_suspend;
+                *ret_modes = sleep_config->suspend_modes;
+                *ret_states = sleep_config->suspend_states;
+        } else if (streq(verb, "hibernate")) {
+                *ret_allow = sleep_config->allow_hibernate;
+                *ret_modes = sleep_config->hibernate_modes;
+                *ret_states = sleep_config->hibernate_states;
+        } else if (streq(verb, "hybrid-sleep")) {
+                *ret_allow = sleep_config->allow_hybrid_sleep;
+                *ret_modes = sleep_config->hybrid_modes;
+                *ret_states = sleep_config->hybrid_states;
+        } else if (streq(verb, "suspend-then-hibernate")) {
+                *ret_allow = sleep_config->allow_s2h;
+                *ret_modes = *ret_states = NULL;
+        }
+
+        /* suspend modes empty by default */
+        if ((!ret_modes && !streq(verb, "suspend")) || !ret_states)
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "No modes or states set for %s; Check sleep.conf", verb);
+
+        return 0;
+}
+
+SleepConfig* free_sleep_config(SleepConfig *sc) {
+        if (!sc)
+                return NULL;
+
+        strv_free(sc->suspend_modes);
+        strv_free(sc->suspend_states);
+
+        strv_free(sc->hibernate_modes);
+        strv_free(sc->hibernate_states);
+
+        strv_free(sc->hybrid_modes);
+        strv_free(sc->hybrid_states);
+
+        return mfree(sc);
+}