libobs/util: Add functions to inhibit sleep

These fucntions prevent the computer from going to sleep, hibernating,
or starting up a screen saver.

On linux, it will also attempt to use DBus to prevent gnome/kde/etc
sleep, but it's not necessarily required in order to compile the
library.  Otherwise, it will simply call "xdg-screensaver reset" once
every 30 seconds to reset the screensaver timer.

libobs/CMakeLists.txt

@@ -9,6 +9,12 @@ include_directories(${FFMPEG_INCLUDE_DIRS})
 
 list(REMOVE_ITEM FFMPEG_LIBRARIES ${FFMPEG_AVCODEC_LIBRARIES})
 
+if(UNIX)
+	find_package(DBus QUIET)
+else()
+	set(HAVE_DBUS "0")
+endif()
+
 find_package(ImageMagick QUIET COMPONENTS MagickCore)
 
 if(NOT ImageMagick_MagickCore_FOUND AND NOT FFMPEG_AVCODEC_FOUND)
@@ -103,6 +109,15 @@ elseif(UNIX)
 		util/pipe-posix.c
 		util/platform-nix.c)
 
+	if(DBUS_FOUND)
+		set(libobs_PLATFORM_SOURCES ${libobs_PLATFORM_SOURCES}
+			util/platform-nix-dbus.c)
+		include_directories(${DBUS_INCLUDE_DIRS})
+		set(libobs_PLATFORM_DEPS
+			${libobs_PLATFORM_DEPS}
+			${DBUS_LIBRARIES})
+	endif()
+
 	if(${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD")
 		# use the sysinfo compatibility library on bsd
 		find_package(Libsysinfo REQUIRED)

libobs/obsconfig.h.in

@@ -7,3 +7,4 @@
 #define OBS_PLUGIN_DESTINATION "@OBS_PLUGIN_DESTINATION@"
 #define OBS_RELATIVE_PREFIX "@OBS_RELATIVE_PREFIX@"
 #define OBS_UNIX_STRUCTURE @OBS_UNIX_STRUCTURE@
+#define HAVE_DBUS @HAVE_DBUS@

libobs/util/platform-cocoa.m

@@ -27,6 +27,8 @@
 #include <mach/mach.h>
 #include <mach/mach_time.h>
 
+#include <IOKit/pwr_mgt/IOPMLib.h>
+
 #import <Cocoa/Cocoa.h>
 
 /* clock function selection taken from libc++ */
@@ -231,3 +233,60 @@ void os_end_high_performance(os_performance_token_t *token)
 	}
 }
 
+struct os_inhibit_info {
+	CFStringRef reason;
+	IOPMAssertionID sleep_id;
+	IOPMAssertionID user_id;
+	bool active;
+};
+
+os_inhibit_t *os_inhibit_sleep_create(const char *reason)
+{
+	struct os_inhibit_info *info = bzalloc(sizeof(*info));
+	if (!reason)
+		info->reason = CFStringCreateWithCString(kCFAllocatorDefault,
+				reason, kCFStringEncodingUTF8);
+	else
+		info->reason = CFStringCreateCopy(kCFAllocatorDefault,
+				CFSTR(""));
+
+	return info;
+}
+
+bool os_inhibit_sleep_set_active(os_inhibit_t *info, bool active)
+{
+	IOReturn success;
+
+	if (!info)
+		return false;
+	if (info->active == active)
+		return false;
+
+	if (active) {
+		IOPMAssertionDeclareUserActivity(info->reason,
+				kIOPMUserActiveLocal, &info->user_id);
+		success = IOPMAssertionCreateWithName(
+				kIOPMAssertionTypeNoDisplaySleep,
+				kIOPMAssertionLevelOn, info->reason,
+				&info->sleep_id);
+
+		if (success != kIOReturnSuccess) {
+			blog(LOG_WARNING, "Failed to disable sleep");
+			return false;
+		}
+	} else {
+		IOPMAssertionRelease(info->sleep_id);
+	}
+
+	info->active = active;
+	return true;
+}
+
+void os_inhibit_sleep_destroy(os_inhibit_t *info)
+{
+	if (info) {
+		os_inhibit_sleep_set_active(info, false);
+		CFRelease(info->reason);
+		bfree(info);
+	}
+}

libobs/util/platform-nix-dbus.c

@@ -0,0 +1,198 @@
+/*
+ * Copyright (c) 2015 Hugh Bailey <obs.jim@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <assert.h>
+#include <dbus/dbus.h>
+#include "bmem.h"
+
+/* NOTE: This is basically just the VLC implementation from its d-bus power
+ * management inhibition code.  Credit is theirs for this. */
+
+enum service_type {
+	FREEDESKTOP_SS, /* freedesktop screensaver (KDE >= 4, GNOME >= 3.10) */
+	FREEDESKTOP_PM, /* freedesktop power management (KDE, gnome <= 2.26) */
+	MATE_SM,        /* MATE (>= 1.0) session manager */
+	GNOME_SM,       /* GNOME 2.26 - 3.4 sessopm mamager */
+};
+
+struct service_info {
+	const char *name;
+	const char *path;
+	const char *uninhibit;
+};
+
+static const struct service_info services[] = {
+	[FREEDESKTOP_SS] = {
+		.name      = "org.freedesktop.ScreenSaver",
+		.path      = "/ScreenSaver",
+		.uninhibit = "UnInhibit",
+	},
+	[FREEDESKTOP_PM] = {
+		.name      = "org.freedesktop.PowerManagement.Inhibit",
+		.path      = "/org/freedesktop/PowerManagement",
+		.uninhibit = "UnInhibit",
+	},
+	[MATE_SM] = {
+		.name      = "org.mate.SessionManager",
+		.path      = "/org/mate/SessionManager",
+		.uninhibit = "Uninhibit",
+	},
+	[GNOME_SM] = {
+		.name      = "org.gnome.SessionManager",
+		.path      = "/org/gnome/SessionManager",
+		.uninhibit = "Uninhibit",
+	},
+};
+
+static const size_t num_services =
+	(sizeof(services) / sizeof(struct service_info));
+
+struct dbus_sleep_info {
+	const struct service_info *service;
+	DBusPendingCall *pending;
+	DBusConnection *c;
+	dbus_uint32_t id;
+	enum service_type type;
+};
+
+void dbus_sleep_info_destroy(struct dbus_sleep_info *info)
+{
+	if (info) {
+		if (info->pending) {
+			dbus_pending_call_cancel(info->pending);
+			dbus_pending_call_unref(info->pending);
+		}
+
+		dbus_connection_close(info->c);
+		dbus_connection_unref(info->c);
+		bfree(info);
+	}
+}
+
+struct dbus_sleep_info *dbus_sleep_info_create(void)
+{
+	struct dbus_sleep_info *info = bzalloc(sizeof(*info));
+	DBusError err;
+
+	dbus_error_init(&err);
+
+	info->c = dbus_bus_get_private(DBUS_BUS_SESSION, &err);
+	if (!info->c) {
+		blog(LOG_ERROR, "Could not create dbus connection: %s",
+				err.message);
+		bfree(info);
+		return NULL;
+	}
+
+	for (size_t i = 0; i < num_services; i++) {
+		const struct service_info *service = &services[i];
+
+		if (!service->name)
+			continue;
+
+		if (dbus_bus_name_has_owner(info->c, service->name, NULL)) {
+			blog(LOG_DEBUG, "Found dbus service: %s",
+					service->name);
+			info->service = service;
+			info->type = (enum service_type)i;
+			return info;
+		}
+	}
+
+	dbus_sleep_info_destroy(info);
+	return NULL;
+}
+
+void dbus_inhibit_sleep(struct dbus_sleep_info *info, const char *reason,
+		bool active)
+{
+	DBusMessage *reply;
+	const char *method;
+	dbus_bool_t success;
+
+	if (info->pending) {
+
+		dbus_pending_call_block(info->pending);
+		reply = dbus_pending_call_steal_reply(info->pending);
+		dbus_pending_call_unref(info->pending);
+		info->pending = NULL;
+
+		if (reply) {
+			success = dbus_message_get_args(reply, NULL,
+					DBUS_TYPE_UINT32, &info->id,
+					DBUS_TYPE_INVALID);
+			if (!success)
+				info->id = 0;
+			dbus_message_unref(reply);
+		}
+	}
+
+	if (active == !!info->id)
+		return;
+
+	method = active ? "Inhibit" : info->service->uninhibit;
+
+	reply = dbus_message_new_method_call(info->service->name,
+			info->service->path, info->service->name, method);
+	if (reply == NULL) {
+		blog(LOG_ERROR, "dbus_message_new_method_call failed");
+		return;
+	}
+
+	if (active) {
+		const char *program = "libobs";
+		dbus_uint32_t flags = 0xC;
+		dbus_uint32_t xid = 0;
+
+		assert(info->id == 0);
+
+		switch (info->type) {
+		case MATE_SM:
+		case GNOME_SM:
+			success = dbus_message_append_args(reply,
+					DBUS_TYPE_STRING, &program,
+					DBUS_TYPE_UINT32, &xid,
+					DBUS_TYPE_STRING, &reason,
+					DBUS_TYPE_UINT32, &flags,
+					DBUS_TYPE_INVALID);
+			break;
+		default:
+			success = dbus_message_append_args(reply,
+					DBUS_TYPE_STRING, &program,
+					DBUS_TYPE_STRING, &reason,
+					DBUS_TYPE_INVALID);
+		}
+
+		if (success) {
+			success = dbus_connection_send_with_reply(info->c,
+					reply, &info->pending, -1);
+			if (!success)
+				info->pending = NULL;
+		}
+	} else {
+		assert(info->id != 0);
+		success = dbus_message_append_args(reply,
+				DBUS_TYPE_UINT32, &info->id,
+				DBUS_TYPE_INVALID);
+		if (success)
+			success = dbus_connection_send(info->c, reply, NULL);
+		if (!success)
+			info->id = 0;
+	}
+
+	dbus_connection_flush(info->c);
+	dbus_message_unref(reply);
+}

libobs/util/platform-nix.c

@@ -25,13 +25,19 @@
 #include <glob.h>
 #include <time.h>
 
+#include "obsconfig.h"
+
 #if !defined(__APPLE__)
 #include <sys/times.h>
+#include <sys/wait.h>
+#include <signal.h>
+#include <spawn.h>
 #endif
 
 #include "darray.h"
 #include "dstr.h"
 #include "platform.h"
+#include "threading.h"
 
 void *os_dlopen(const char *path)
 {
@@ -422,3 +428,125 @@ int os_chdir(const char *path)
 {
 	return chdir(path);
 }
+
+#if !defined(__APPLE__)
+
+#if HAVE_DBUS
+struct dbus_sleep_info;
+
+extern struct dbus_sleep_info *dbus_sleep_info_create(void);
+extern void dbus_inhibit_sleep(struct dbus_sleep_info *dbus, const char *sleep,
+		bool active);
+extern void dbus_sleep_info_destroy(struct dbus_sleep_info *dbus);
+#endif
+
+struct os_inhibit_info {
+#if HAVE_DBUS
+	struct dbus_sleep_info *dbus;
+#endif
+	pthread_t screensaver_thread;
+	os_event_t *stop_event;
+	char *reason;
+	posix_spawnattr_t attr;
+	bool active;
+};
+
+os_inhibit_t *os_inhibit_sleep_create(const char *reason)
+{
+	struct os_inhibit_info *info = bzalloc(sizeof(*info));
+	sigset_t set;
+
+#if HAVE_DBUS
+	info->dbus = dbus_sleep_info_create();
+#endif
+
+	os_event_init(&info->stop_event, OS_EVENT_TYPE_AUTO);
+	posix_spawnattr_init(&info->attr);
+
+	sigemptyset(&set);
+	posix_spawnattr_setsigmask(&info->attr, &set);
+	sigaddset(&set, SIGPIPE);
+	posix_spawnattr_setsigdefault(&info->attr, &set);
+	posix_spawnattr_setflags(&info->attr,
+			POSIX_SPAWN_SETSIGDEF | POSIX_SPAWN_SETSIGMASK);
+
+	info->reason = bstrdup(reason);
+	return info;
+}
+
+extern char **environ;
+
+static void reset_screensaver(os_inhibit_t *info)
+{
+	char *argv[3] = {(char*)"xdg-screensaver", (char*)"reset", NULL};
+	pid_t pid;
+
+	int err = posix_spawnp(&pid, "xdg-screensaver", NULL, &info->attr,
+			argv, environ);
+	if (err == 0) {
+		int status;
+		while (waitpid(pid, &status, 0) == -1);
+	} else {
+		blog(LOG_WARNING, "Failed to create xdg-screensaver: %d", err);
+	}
+}
+
+static void *screensaver_thread(void *param)
+{
+	os_inhibit_t *info = param;
+
+	while (os_event_timedwait(info->stop_event, 30000) == ETIMEDOUT)
+		reset_screensaver(info);
+
+	return NULL;
+}
+
+bool os_inhibit_sleep_set_active(os_inhibit_t *info, bool active)
+{
+	int ret;
+
+	if (!info)
+		return false;
+	if (info->active == active)
+		return false;
+
+#if HAVE_DBUS
+	if (info->dbus)
+		dbus_inhibit_sleep(info->dbus, info->reason, active);
+#endif
+
+	if (!info->stop_event)
+		return true;
+
+	if (active) {
+		ret = pthread_create(&info->screensaver_thread, NULL,
+				&screensaver_thread, info);
+		if (ret < 0) {
+			blog(LOG_ERROR, "Failed to create screensaver "
+			                "inhibitor thread");
+			return false;
+		}
+	} else {
+		os_event_signal(info->stop_event);
+		pthread_join(info->screensaver_thread, NULL);
+	}
+
+	info->active = active;
+	return true;
+}
+
+void os_inhibit_sleep_destroy(os_inhibit_t *info)
+{
+	if (info) {
+		os_inhibit_sleep_set_active(info, false);
+#if HAVE_DBUS
+		dbus_sleep_info_destroy(info->dbus);
+#endif
+		os_event_destroy(info->stop_event);
+		posix_spawnattr_destroy(&info->attr);
+		bfree(info->reason);
+		bfree(info);
+	}
+}
+
+#endif

libobs/util/platform-windows.c

@@ -666,3 +666,49 @@ void get_win_ver(struct win_version_info *info)
 
 	*info = ver;
 }
+
+struct os_inhibit_info {
+	BOOL was_active;
+	bool active;
+};
+
+os_inhibit_t *os_inhibit_sleep_create(const char *reason)
+{
+	UNUSED_PARAMETER(reason);
+	return bzalloc(sizeof(struct os_inhibit_info));
+}
+
+bool os_inhibit_sleep_set_active(os_inhibit_t *info, bool active)
+{
+	if (!info)
+		return false;
+	if (info->active == active)
+		return false;
+
+	if (active) {
+		SystemParametersInfo(SPI_GETSCREENSAVEACTIVE, 0,
+				&info->was_active, 0);
+		SystemParametersInfo(SPI_SETSCREENSAVEACTIVE, false,
+				NULL, 0);
+		SetThreadExecutionState(
+				ES_CONTINUOUS |
+				ES_SYSTEM_REQUIRED |
+				ES_AWAYMODE_REQUIRED |
+				ES_DISPLAY_REQUIRED);
+	} else {
+		SystemParametersInfo(SPI_SETSCREENSAVEACTIVE, info->was_active,
+				NULL, 0);
+		SetThreadExecutionState(ES_CONTINUOUS);
+	}
+
+	info->active = active;
+	return true;
+}
+
+void os_inhibit_sleep_destroy(os_inhibit_t *info)
+{
+	if (info) {
+		os_inhibit_sleep_set_active(info, false);
+		bfree(info);
+	}
+}

libobs/util/platform.h

@@ -145,6 +145,13 @@ EXPORT int os_mkdirs(const char *path);
 EXPORT int os_rename(const char *old_path, const char *new_path);
 EXPORT int os_copyfile(const char *file_in, const char *file_out);
 
+struct os_inhibit_info;
+typedef struct os_inhibit_info os_inhibit_t;
+
+EXPORT os_inhibit_t *os_inhibit_sleep_create(const char *reason);
+EXPORT bool os_inhibit_sleep_set_active(os_inhibit_t *info, bool active);
+EXPORT void os_inhibit_sleep_destroy(os_inhibit_t *info);
+
 #ifdef _MSC_VER
 #define strtoll _strtoi64
 #if _MSC_VER < 1900