/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include "sd-device.h" #include "battery-capacity.h" #include "battery-util.h" #include "device-private.h" #include "device-util.h" #include "extract-word.h" #include "fd-util.h" #include "fileio.h" #include "hexdecoct.h" #include "id128-util.h" #include "parse-util.h" #include "siphash24.h" #define DISCHARGE_RATE_FILEPATH "/var/lib/systemd/sleep/battery_discharge_percentage_rate_per_hour" #define BATTERY_DISCHARGE_RATE_HASH_KEY SD_ID128_MAKE(5f,9a,20,18,38,76,46,07,8d,36,58,0b,bb,c4,e0,63) static void *CAPACITY_TO_PTR(int capacity) { assert(capacity >= 0); assert(capacity <= 100); return INT_TO_PTR(capacity + 1); } static int PTR_TO_CAPACITY(void *p) { int capacity = PTR_TO_INT(p) - 1; assert(capacity >= 0); assert(capacity <= 100); return capacity; } static int siphash24_compress_device_sysattr( sd_device *dev, const char *attr, struct siphash *state) { const char *x; int r; assert(dev); assert(attr); assert(state); r = sd_device_get_sysattr_value(dev, attr, &x); if (r < 0) return log_device_debug_errno(dev, r, "Failed to read '%s' attribute: %m", attr); if (!isempty(x)) siphash24_compress_string(x, state); return 0; } static int siphash24_compress_id128( int (*getter)(sd_id128_t *ret), const char *name, struct siphash *state) { sd_id128_t id; int r; assert(getter); assert(name); assert(state); r = getter(&id); if (r < 0) return log_debug_errno(r, "Failed to get %s ID: %m", name); siphash24_compress_typesafe(id, state); return 0; } /* Read system and battery identifier from specific location and generate hash of it */ static uint64_t system_battery_identifier_hash(sd_device *dev) { struct siphash state; assert(dev); siphash24_init(&state, BATTERY_DISCHARGE_RATE_HASH_KEY.bytes); (void) siphash24_compress_device_sysattr(dev, "manufacturer", &state); (void) siphash24_compress_device_sysattr(dev, "model_name", &state); (void) siphash24_compress_device_sysattr(dev, "serial_number", &state); (void) siphash24_compress_id128(sd_id128_get_machine, "machine", &state); (void) siphash24_compress_id128(id128_get_product, "product", &state); return siphash24_finalize(&state); } /* Return success if battery percentage discharge rate per hour is in the range 1–199 */ static bool battery_discharge_rate_is_valid(int battery_discharge_rate) { return battery_discharge_rate > 0 && battery_discharge_rate < 200; } /* Battery percentage discharge rate per hour is read from specific file. It is stored along with system * and battery identifier hash to maintain the integrity of discharge rate value */ static int get_battery_discharge_rate(sd_device *dev, int *ret) { _cleanup_fclose_ FILE *f = NULL; uint64_t current_hash_id; const char *p; int r; assert(dev); assert(ret); f = fopen(DISCHARGE_RATE_FILEPATH, "re"); if (!f) return log_debug_errno(errno, "Failed to read discharge rate from " DISCHARGE_RATE_FILEPATH ": %m"); current_hash_id = system_battery_identifier_hash(dev); for (;;) { _cleanup_free_ char *stored_hash_id = NULL, *stored_discharge_rate = NULL, *line = NULL; uint64_t hash_id; int discharge_rate; r = read_line(f, LONG_LINE_MAX, &line); if (r < 0) return log_debug_errno(r, "Failed to read discharge rate from " DISCHARGE_RATE_FILEPATH ": %m"); if (r == 0) break; p = line; r = extract_many_words(&p, NULL, 0, &stored_hash_id, &stored_discharge_rate); if (r < 0) return log_debug_errno(r, "Failed to parse hash_id and discharge_rate read from " DISCHARGE_RATE_FILEPATH ": %m"); if (r != 2) return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Invalid number of items fetched from " DISCHARGE_RATE_FILEPATH); r = safe_atou64(stored_hash_id, &hash_id); if (r < 0) return log_debug_errno(r, "Failed to parse hash ID read from " DISCHARGE_RATE_FILEPATH " location: %m"); if (current_hash_id != hash_id) /* matching device not found, move to next line */ continue; r = safe_atoi(stored_discharge_rate, &discharge_rate); if (r < 0) return log_device_debug_errno(dev, r, "Failed to parse discharge rate read from " DISCHARGE_RATE_FILEPATH ": %m"); if (!battery_discharge_rate_is_valid(discharge_rate)) return log_device_debug_errno(dev, SYNTHETIC_ERRNO(ERANGE), "Invalid battery discharge percentage rate per hour."); *ret = discharge_rate; return 0; /* matching device found, exit iteration */ } return -ENOENT; } /* Write battery percentage discharge rate per hour along with system and battery identifier hash to file */ static int put_battery_discharge_rate(int estimated_battery_discharge_rate, uint64_t system_hash_id, bool trunc) { int r; if (!battery_discharge_rate_is_valid(estimated_battery_discharge_rate)) return log_debug_errno(SYNTHETIC_ERRNO(ERANGE), "Invalid battery discharge rate %d%% per hour.", estimated_battery_discharge_rate); r = write_string_filef( DISCHARGE_RATE_FILEPATH, WRITE_STRING_FILE_CREATE | WRITE_STRING_FILE_MKDIR_0755 | (trunc ? WRITE_STRING_FILE_TRUNCATE : 0), "%"PRIu64" %d", system_hash_id, estimated_battery_discharge_rate); if (r < 0) return log_debug_errno(r, "Failed to update %s: %m", DISCHARGE_RATE_FILEPATH); log_debug("Estimated discharge rate %d%% per hour successfully saved to %s", estimated_battery_discharge_rate, DISCHARGE_RATE_FILEPATH); return 0; } /* Store current capacity of each battery before suspension and timestamp */ int fetch_batteries_capacity_by_name(Hashmap **ret) { _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; _cleanup_hashmap_free_ Hashmap *batteries_capacity_by_name = NULL; int r; assert(ret); batteries_capacity_by_name = hashmap_new(&string_hash_ops_free); if (!batteries_capacity_by_name) return log_oom_debug(); r = battery_enumerator_new(&e); if (r < 0) return log_debug_errno(r, "Failed to initialize battery enumerator: %m"); FOREACH_DEVICE(e, dev) { _cleanup_free_ char *battery_name_copy = NULL; const char *battery_name; int battery_capacity; battery_capacity = r = battery_read_capacity_percentage(dev); if (r < 0) continue; r = sd_device_get_property_value(dev, "POWER_SUPPLY_NAME", &battery_name); if (r < 0) { log_device_debug_errno(dev, r, "Failed to get POWER_SUPPLY_NAME property, ignoring: %m"); continue; } battery_name_copy = strdup(battery_name); if (!battery_name_copy) return log_oom_debug(); r = hashmap_put(batteries_capacity_by_name, battery_name_copy, CAPACITY_TO_PTR(battery_capacity)); if (r < 0) return log_device_debug_errno(dev, r, "Failed to store battery capacity: %m"); TAKE_PTR(battery_name_copy); } *ret = TAKE_PTR(batteries_capacity_by_name); return 0; } int get_capacity_by_name(Hashmap *capacities_by_name, const char *name) { void *p; assert(capacities_by_name); assert(name); p = hashmap_get(capacities_by_name, name); if (!p) return -ENOENT; return PTR_TO_CAPACITY(p); } /* Estimate battery discharge rate using stored previous and current capacity over timestamp difference */ int estimate_battery_discharge_rate_per_hour( Hashmap *last_capacity, Hashmap *current_capacity, usec_t before_timestamp, usec_t after_timestamp) { _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; bool trunc = true; int r; assert(last_capacity); assert(current_capacity); assert(before_timestamp < after_timestamp); r = battery_enumerator_new(&e); if (r < 0) return log_debug_errno(r, "Failed to initialize battery enumerator: %m"); FOREACH_DEVICE(e, dev) { int battery_last_capacity, battery_current_capacity, battery_discharge_rate; const char *battery_name; uint64_t system_hash_id; r = sd_device_get_property_value(dev, "POWER_SUPPLY_NAME", &battery_name); if (r < 0) { log_device_debug_errno(dev, r, "Failed to read battery name, ignoring: %m"); continue; } battery_last_capacity = get_capacity_by_name(last_capacity, battery_name); if (battery_last_capacity < 0) continue; battery_current_capacity = get_capacity_by_name(current_capacity, battery_name); if (battery_current_capacity < 0) continue; if (battery_current_capacity >= battery_last_capacity) { log_device_debug(dev, "Battery was not discharged during suspension"); continue; } system_hash_id = system_battery_identifier_hash(dev); log_device_debug(dev, "%d%% was discharged in %s. Estimating discharge rate...", battery_last_capacity - battery_current_capacity, FORMAT_TIMESPAN(after_timestamp - before_timestamp, USEC_PER_SEC)); battery_discharge_rate = (battery_last_capacity - battery_current_capacity) * USEC_PER_HOUR / (after_timestamp - before_timestamp); r = put_battery_discharge_rate(battery_discharge_rate, system_hash_id, trunc); if (r < 0) log_device_warning_errno(dev, r, "Failed to update battery discharge rate, ignoring: %m"); else trunc = false; } return 0; } /* Calculate the suspend interval for each battery and then return their sum */ int get_total_suspend_interval(Hashmap *last_capacity, usec_t *ret) { _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; usec_t total_suspend_interval = 0; int r; assert(last_capacity); assert(ret); r = battery_enumerator_new(&e); if (r < 0) return log_debug_errno(r, "Failed to initialize battery enumerator: %m"); FOREACH_DEVICE(e, dev) { int battery_last_capacity, previous_discharge_rate = 0; const char *battery_name; usec_t suspend_interval; r = sd_device_get_property_value(dev, "POWER_SUPPLY_NAME", &battery_name); if (r < 0) { log_device_debug_errno(dev, r, "Failed to read battery name, ignoring: %m"); continue; } battery_last_capacity = get_capacity_by_name(last_capacity, battery_name); if (battery_last_capacity <= 0) continue; r = get_battery_discharge_rate(dev, &previous_discharge_rate); if (r < 0) { log_device_debug_errno(dev, r, "Failed to get discharge rate, ignoring: %m"); continue; } if (previous_discharge_rate == 0) continue; if (battery_last_capacity * 2 <= previous_discharge_rate) { log_device_debug(dev, "Current battery capacity percentage too low compared to discharge rate"); continue; } suspend_interval = battery_last_capacity * USEC_PER_HOUR / previous_discharge_rate; total_suspend_interval = usec_add(total_suspend_interval, suspend_interval); } /* Previous discharge rate is stored in per hour basis converted to usec. * Subtract 30 minutes from the result to keep a buffer of 30 minutes before battery gets critical */ total_suspend_interval = usec_sub_unsigned(total_suspend_interval, 30 * USEC_PER_MINUTE); if (total_suspend_interval == 0) return -ENOENT; *ret = total_suspend_interval; return 0; } /* Return true if all batteries have acpi_btp support */ int battery_trip_point_alarm_exists(void) { _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; bool has_battery = false; int r; r = battery_enumerator_new(&e); if (r < 0) return log_debug_errno(r, "Failed to initialize battery enumerator: %m"); FOREACH_DEVICE(e, dev) { const char *alarm_attr; int has_alarm; has_battery = true; r = sd_device_get_sysattr_value(dev, "alarm", &alarm_attr); if (r < 0) return log_device_debug_errno(dev, r, "Failed to read battery alarm attribute: %m"); r = safe_atoi(alarm_attr, &has_alarm); if (r < 0) return log_device_debug_errno(dev, r, "Failed to parse battery alarm attribute '%s': %m", alarm_attr); if (has_alarm <= 0) return false; } return has_battery; }