Standardize state_file handling routines.

This way it's easier to manage and extend.

git-svn-id: https://svn.musicpd.org/mpd/trunk@4494 09075e82-0dd4-0310-85a5-a0d7c8717e4f

9 files changed, 261 insertions, 232 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 3c5d46990..1dfcd476e 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -64,6 +64,7 @@ mpd_headers = \
 	sig_handlers.h \
 	sllist.h \
 	song.h \
+	state_file.h \
 	stats.h \
 	tag.h \
 	tagTracker.h \
@@ -111,6 +112,7 @@ mpd_SOURCES = \
 	signal_check.c \
 	sllist.c \
 	song.c \
+	state_file.c \
 	stats.c \
 	tag.c \
 	tagTracker.c \
diff --git a/src/audio.c b/src/audio.c
index 8ecae5ec3..b4f0dadc3 100644
--- a/src/audio.c
+++ b/src/audio.c
@@ -25,6 +25,7 @@
 #include "playerData.h"
 #include "utils.h"
 #include "playlist.h"
+#include "state_file.h"
 
 #include <stdlib.h>
 #include <string.h>
@@ -462,32 +463,19 @@ void printAudioDevices(int fd)
 	}
 }
 
-void saveAudioDevicesState(void)
+void saveAudioDevicesState(FILE *fp)
 {
-	char *stateFile;
-	FILE *fp;
 	int i;
 
-	if (!(stateFile = getStateFile()))
-		return;
-
-	while (!(fp = fopen(stateFile, "a")) && errno == EINTR) ;
-	if (!fp) {
-		ERROR("problems opening state file \"%s\" for "
-		      "writing: %s\n", stateFile, strerror(errno));
-		return;
-	}
-
 	assert(audioOutputArraySize != 0);
 	for (i = 0; i < audioOutputArraySize; i++) {
 		fprintf(fp, AUDIO_DEVICE_STATE "%d:%s\n",
-			  (int)pdAudioDevicesEnabled[i],
-			  audioOutputArray[i]->name);
+			(int)pdAudioDevicesEnabled[i],
+		        audioOutputArray[i]->name);
 	}
-	while (fclose(fp) && errno == EINTR) ;
 }
 
-static void parse_audio_device_state(FILE * fp)
+void readAudioDevicesState(FILE *fp)
 {
 	char buffer[AUDIO_BUFFER_SIZE];
 	int i;
@@ -521,29 +509,3 @@ static void parse_audio_device_state(FILE * fp)
 	}
 }
 
-void readAudioDevicesState(void)
-{
-	char *stateFile;
-	FILE *fp;
-	struct stat st;
-
-	if (!(stateFile = getStateFile()))
-		return;
-	if (stat(stateFile, &st) < 0) {
-		DEBUG("failed to stat state file\n");
-		return;
-	}
-	if (!S_ISREG(st.st_mode)) {
-		ERROR("state file \"%s\" is not a regular file\n", stateFile);
-		exit(EXIT_FAILURE);
-	}
-
-	fp = fopen(stateFile, "r");
-	if (!fp) {
-		ERROR("problems opening state file \"%s\" for "
-		      "reading: %s\n", stateFile, strerror(errno));
-		exit(EXIT_FAILURE);
-	}
-	parse_audio_device_state(fp);
-	fclose(fp);
-}
diff --git a/src/audio.h b/src/audio.h
index 29309b9ce..70cc551fd 100644
--- a/src/audio.h
+++ b/src/audio.h
@@ -75,9 +75,9 @@ int disableAudioDevice(int fd, int device);
 
 void printAudioDevices(int fd);
 
-void readAudioDevicesState();
+void readAudioDevicesState(FILE *fp);
 
-void saveAudioDevicesState();
+void saveAudioDevicesState(FILE *fp);
 
 void loadAudioDrivers();
 #endif
diff --git a/src/main.c b/src/main.c
index 67ae0f76b..3ba2afeb4 100644
--- a/src/main.c
+++ b/src/main.c
@@ -35,6 +35,7 @@
 #include "inputPlugin.h"
 #include "audioOutput.h"
 #include "inputStream.h"
+#include "state_file.h"
 #include "tag.h"
 #include "tagTracker.h"
 #include "dbUtils.h"
@@ -346,7 +347,6 @@ static void startMainProcess(void)
 	if (pid > 0) {
 		initInputStream();
 		initReplayGainState();
-		readAudioDevicesState();
 
 		/* free stuff we don't need */
 		freeAllListenSockets();
@@ -581,7 +581,7 @@ int main(int argc, char *argv[])
 		my_usleep(1);
 
 	openVolumeDevice();
-	readPlaylistState();
+	read_state_file();
 
 	while (COMMAND_RETURN_KILL != doIOForInterfaces()) {
 		if (COMMAND_RETURN_KILL == handlePendingSignals())
@@ -591,8 +591,7 @@ int main(int argc, char *argv[])
 		readDirectoryDBIfUpdateIsFinished();
 	}
 
-	savePlaylistState();
-	saveAudioDevicesState();
+	write_state_file();
 
 	freeAllInterfaces();
 	closeAllListenSockets();
diff --git a/src/playlist.c b/src/playlist.c
index 64350d471..359e3ac24 100644
--- a/src/playlist.c
+++ b/src/playlist.c
@@ -27,6 +27,7 @@
 #include "path.h"
 #include "utils.h"
 #include "sig_handlers.h"
+#include "state_file.h"
 
 #include <string.h>
 #include <stdlib.h>
@@ -92,16 +93,6 @@ static void swapOrder(int a, int b);
 static int playPlaylistOrderNumber(int fd, int orderNum);
 static void randomizeOrder(int start, int end);
 
-char *getStateFile(void)
-{
-	ConfigParam *param = parseConfigFilePath(CONF_STATE_FILE, 0);
-
-	if (!param)
-		return NULL;
-
-	return param->value;
-}
-
 static void incrPlaylistVersion(void)
 {
 	static unsigned long max = ((mpd_uint32) 1 << 31) - 1;
@@ -256,208 +247,141 @@ int showPlaylist(int fd)
 	return 0;
 }
 
-void savePlaylistState(void)
+void savePlaylistState(FILE *fp)
 {
-	char *stateFile = getStateFile();
-
-	if (stateFile) {
-		FILE *fp;
-
-		while (!(fp = fopen(stateFile, "w")) && errno == EINTR) ;
-		if (!fp) {
-			ERROR("problems opening state file \"%s\" for "
-			      "writing: %s\n", stateFile, strerror(errno));
-			return;
-		}
-
-		fprintf(fp, "%s", PLAYLIST_STATE_FILE_STATE);
-		switch (playlist_state) {
-		case PLAYLIST_STATE_PLAY:
-			switch (getPlayerState()) {
-			case PLAYER_STATE_PAUSE:
-				fprintf(fp, "%s\n",
-					  PLAYLIST_STATE_FILE_STATE_PAUSE);
-				break;
-			default:
-				fprintf(fp, "%s\n",
-					  PLAYLIST_STATE_FILE_STATE_PLAY);
-			}
-			fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_CURRENT,
-				  playlist.order[playlist.current]);
-			fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_TIME,
-				  getPlayerElapsedTime());
+	fprintf(fp, "%s", PLAYLIST_STATE_FILE_STATE);
+	switch (playlist_state) {
+	case PLAYLIST_STATE_PLAY:
+		switch (getPlayerState()) {
+		case PLAYER_STATE_PAUSE:
+			fprintf(fp, "%s\n", PLAYLIST_STATE_FILE_STATE_PAUSE);
 			break;
 		default:
-			fprintf(fp, "%s\n", PLAYLIST_STATE_FILE_STATE_STOP);
-			break;
+			fprintf(fp, "%s\n", PLAYLIST_STATE_FILE_STATE_PLAY);
 		}
-		fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_RANDOM,
-			  playlist.random);
-		fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_REPEAT,
-			  playlist.repeat);
-		fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_CROSSFADE,
-			  (int)(getPlayerCrossFade()));
-		fprintf(fp, "%s\n", PLAYLIST_STATE_FILE_PLAYLIST_BEGIN);
-		fflush(fp);
-		showPlaylist(fileno(fp));
-		fprintf(fp, "%s\n", PLAYLIST_STATE_FILE_PLAYLIST_END);
-
-		while (fclose(fp) && errno == EINTR) ;
+		fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_CURRENT,
+		        playlist.order[playlist.current]);
+		fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_TIME,
+		        getPlayerElapsedTime());
+		break;
+	default:
+		fprintf(fp, "%s\n", PLAYLIST_STATE_FILE_STATE_STOP);
+		break;
 	}
+	fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_RANDOM, playlist.random);
+	fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_REPEAT, playlist.repeat);
+	fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_CROSSFADE,
+	        (int)(getPlayerCrossFade()));
+	fprintf(fp, "%s\n", PLAYLIST_STATE_FILE_PLAYLIST_BEGIN);
+	fflush(fp);
+	showPlaylist(fileno(fp));
+	fprintf(fp, "%s\n", PLAYLIST_STATE_FILE_PLAYLIST_END);
 }
 
-void loadPlaylistFromStateFile(FILE *fp, char *buffer, int state, int current,
-			       int time)
+static void loadPlaylistFromStateFile(FILE *fp, char *buffer,
+				      int state, int current, int time)
 {
 	char *temp;
 	int song;
-	char *stateFile = getStateFile();
 
-	if (!myFgets(buffer, PLAYLIST_BUFFER_SIZE, fp)) {
-		ERROR("error parsing state file \"%s\"\n", stateFile);
-		exit(EXIT_FAILURE);
-	}
+	if (!myFgets(buffer, PLAYLIST_BUFFER_SIZE, fp))
+		state_file_fatal();
 	while (strcmp(buffer, PLAYLIST_STATE_FILE_PLAYLIST_END)) {
 		song = atoi(strtok(buffer, ":"));
-		if (!(temp = strtok(NULL, ""))) {
-			ERROR("error parsing state file \"%s\"\n", stateFile);
-			exit(EXIT_FAILURE);
-		}
+		if (!(temp = strtok(NULL, "")))
+			state_file_fatal();
 		if (!addToPlaylist(STDERR_FILENO, temp, 0) && current == song) {
 			if (state != PLAYER_STATE_STOP) {
 				playPlaylist(STDERR_FILENO,
-				             playlist.length - 1, 0);
+					     playlist.length - 1, 0);
 			}
 			if (state == PLAYER_STATE_PAUSE) {
 				playerPause(STDERR_FILENO);
 			}
 			if (state != PLAYER_STATE_STOP) {
 				seekSongInPlaylist(STDERR_FILENO,
-				                   playlist.length - 1,
-						   time);
+						   playlist.length - 1, time);
 			}
 		}
-		if (!myFgets(buffer, PLAYLIST_BUFFER_SIZE, fp)) {
-			ERROR("error parsing state file \"%s\"\n", stateFile);
-			exit(EXIT_FAILURE);
-		}
+		if (!myFgets(buffer, PLAYLIST_BUFFER_SIZE, fp))
+			state_file_fatal();
 	}
 }
 
-void readPlaylistState(void)
+void readPlaylistState(FILE *fp)
 {
-	char *stateFile = getStateFile();
-
-	if (stateFile) {
-		FILE *fp;
-		struct stat st;
-		int current = -1;
-		int time = 0;
-		int state = PLAYER_STATE_STOP;
-		char buffer[PLAYLIST_BUFFER_SIZE];
-
-		if (stat(stateFile, &st) < 0) {
-			DEBUG("failed to stat state file\n");
-			return;
-		}
-		if (!S_ISREG(st.st_mode)) {
-			ERROR("state file \"%s\" is not a regular "
-			      "file\n", stateFile);
-			exit(EXIT_FAILURE);
-		}
+	int current = -1;
+	int time = 0;
+	int state = PLAYER_STATE_STOP;
+	char buffer[PLAYLIST_BUFFER_SIZE];
 
-		fp = fopen(stateFile, "r");
-		if (!fp) {
-			ERROR("problems opening state file \"%s\" for "
-			      "reading: %s\n", stateFile, strerror(errno));
-			exit(EXIT_FAILURE);
-		}
-
-		while (myFgets(buffer, PLAYLIST_BUFFER_SIZE, fp)) {
-			if (strncmp(buffer, PLAYLIST_STATE_FILE_STATE,
-				    strlen(PLAYLIST_STATE_FILE_STATE)) == 0) {
-				if (strcmp(&(buffer
-					     [strlen
-					      (PLAYLIST_STATE_FILE_STATE)]),
-					   PLAYLIST_STATE_FILE_STATE_PLAY) ==
-				    0) {
-					state = PLAYER_STATE_PLAY;
-				} else if (strcmp(&(buffer
-						    [strlen
-						     (PLAYLIST_STATE_FILE_STATE)]),
-						  PLAYLIST_STATE_FILE_STATE_PAUSE)
-					   == 0) {
-					state = PLAYER_STATE_PAUSE;
-				}
-			} else if (strncmp(buffer, PLAYLIST_STATE_FILE_TIME,
-					   strlen(PLAYLIST_STATE_FILE_TIME)) ==
-				   0) {
-				time =
-				    atoi(&
-					 (buffer
-					  [strlen(PLAYLIST_STATE_FILE_TIME)]));
-			} else
-			    if (strncmp
-				(buffer, PLAYLIST_STATE_FILE_REPEAT,
-				 strlen(PLAYLIST_STATE_FILE_REPEAT)) == 0) {
-				if (strcmp
-				    (&
-				     (buffer
-				      [strlen(PLAYLIST_STATE_FILE_REPEAT)]),
-				     "1") == 0) {
-					setPlaylistRepeatStatus(STDERR_FILENO,
-					                        1);
-				} else
-					setPlaylistRepeatStatus(STDERR_FILENO,
-					                        0);
+	while (myFgets(buffer, PLAYLIST_BUFFER_SIZE, fp)) {
+		if (strncmp(buffer, PLAYLIST_STATE_FILE_STATE,
+			    strlen(PLAYLIST_STATE_FILE_STATE)) == 0) {
+			if (strcmp(&(buffer[strlen(PLAYLIST_STATE_FILE_STATE)]),
+				   PLAYLIST_STATE_FILE_STATE_PLAY) == 0) {
+				state = PLAYER_STATE_PLAY;
 			} else
-			    if (strncmp
-				(buffer, PLAYLIST_STATE_FILE_CROSSFADE,
-				 strlen(PLAYLIST_STATE_FILE_CROSSFADE)) == 0) {
-				setPlayerCrossFade(atoi
-						   (&
-						    (buffer
-						     [strlen
-						      (PLAYLIST_STATE_FILE_CROSSFADE)])));
+			    if (strcmp
+				(&(buffer[strlen(PLAYLIST_STATE_FILE_STATE)]),
+				 PLAYLIST_STATE_FILE_STATE_PAUSE)
+				== 0) {
+				state = PLAYER_STATE_PAUSE;
+			}
+		} else if (strncmp(buffer, PLAYLIST_STATE_FILE_TIME,
+				   strlen(PLAYLIST_STATE_FILE_TIME)) == 0) {
+			time =
+			    atoi(&(buffer[strlen(PLAYLIST_STATE_FILE_TIME)]));
+		} else
+		    if (strncmp
+			(buffer, PLAYLIST_STATE_FILE_REPEAT,
+			 strlen(PLAYLIST_STATE_FILE_REPEAT)) == 0) {
+			if (strcmp
+			    (&(buffer[strlen(PLAYLIST_STATE_FILE_REPEAT)]),
+			     "1") == 0) {
+				setPlaylistRepeatStatus(STDERR_FILENO, 1);
 			} else
-			    if (strncmp
-				(buffer, PLAYLIST_STATE_FILE_RANDOM,
-				 strlen(PLAYLIST_STATE_FILE_RANDOM)) == 0) {
-				if (strcmp
-				    (&
-				     (buffer
-				      [strlen(PLAYLIST_STATE_FILE_RANDOM)]),
-				     "1") == 0) {
-					setPlaylistRandomStatus(STDERR_FILENO,
-					                        1);
-				} else
-					setPlaylistRandomStatus(STDERR_FILENO,
-					                        0);
-			} else if (strncmp(buffer, PLAYLIST_STATE_FILE_CURRENT,
-					   strlen(PLAYLIST_STATE_FILE_CURRENT))
-				   == 0) {
-				if (strlen(buffer) ==
-				    strlen(PLAYLIST_STATE_FILE_CURRENT)) {
-					ERROR("error parsing state "
-					      "file \"%s\"\n", stateFile);
-					exit(EXIT_FAILURE);
-				}
-				current = atoi(&(buffer
-						 [strlen
-						  (PLAYLIST_STATE_FILE_CURRENT)]));
+				setPlaylistRepeatStatus(STDERR_FILENO, 0);
+		} else
+		    if (strncmp
+			(buffer, PLAYLIST_STATE_FILE_CROSSFADE,
+			 strlen(PLAYLIST_STATE_FILE_CROSSFADE)) == 0) {
+			setPlayerCrossFade(atoi
+					   (&
+					    (buffer
+					     [strlen
+					      (PLAYLIST_STATE_FILE_CROSSFADE)])));
+		} else
+		    if (strncmp
+			(buffer, PLAYLIST_STATE_FILE_RANDOM,
+			 strlen(PLAYLIST_STATE_FILE_RANDOM)) == 0) {
+			if (strcmp
+			    (&
+			     (buffer
+			      [strlen(PLAYLIST_STATE_FILE_RANDOM)]),
+			     "1") == 0) {
+				setPlaylistRandomStatus(STDERR_FILENO, 1);
 			} else
-			    if (strncmp
-				(buffer, PLAYLIST_STATE_FILE_PLAYLIST_BEGIN,
-				 strlen(PLAYLIST_STATE_FILE_PLAYLIST_BEGIN)
-				) == 0) {
-				if (state == PLAYER_STATE_STOP)
-					current = -1;
-				loadPlaylistFromStateFile(fp, buffer, state,
-							  current, time);
-			}
+				setPlaylistRandomStatus(STDERR_FILENO, 0);
+		} else if (strncmp(buffer, PLAYLIST_STATE_FILE_CURRENT,
+				   strlen(PLAYLIST_STATE_FILE_CURRENT))
+			   == 0) {
+			if (strlen(buffer) ==
+			    strlen(PLAYLIST_STATE_FILE_CURRENT))
+				state_file_fatal();
+			current = atoi(&(buffer
+					 [strlen
+					  (PLAYLIST_STATE_FILE_CURRENT)]));
+		} else
+		    if (strncmp
+			(buffer, PLAYLIST_STATE_FILE_PLAYLIST_BEGIN,
+			 strlen(PLAYLIST_STATE_FILE_PLAYLIST_BEGIN)
+			) == 0) {
+			if (state == PLAYER_STATE_STOP)
+				current = -1;
+			loadPlaylistFromStateFile(fp, buffer, state,
+						  current, time);
 		}
-
-		fclose(fp);
 	}
 }
 
diff --git a/src/playlist.h b/src/playlist.h
index 25ed45dfb..837bff161 100644
--- a/src/playlist.h
+++ b/src/playlist.h
@@ -34,9 +34,9 @@ void initPlaylist();
 
 void finishPlaylist();
 
-void readPlaylistState();
+void readPlaylistState(FILE *);
 
-void savePlaylistState();
+void savePlaylistState(FILE *);
 
 int clearPlaylist(int fd);
 
@@ -116,6 +116,4 @@ int playlistChangesPosId(int fd, mpd_uint32 version);
 
 int PlaylistInfo(int fd, char *utf8file, int detail);
 
-char *getStateFile();
-
 #endif
diff --git a/src/state_file.c b/src/state_file.c
new file mode 100644
index 000000000..1307faa54
--- /dev/null
+++ b/src/state_file.c
@@ -0,0 +1,112 @@
+/* the Music Player Daemon (MPD)
+ * (c)2003-2006 by Warren Dukes (warren.dukes@gmail.com)
+ * This project's homepage is: http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "../config.h"
+#include "state_file.h"
+#include "conf.h"
+#include "gcc.h"
+#include "log.h"
+#include "audio.h"
+#include "playlist.h"
+#include "utils.h"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+static struct _sf_cb {
+	void (*reader)(FILE *);
+	void (*writer)(FILE *);
+} sf_callbacks [] = {
+	{ readAudioDevicesState, saveAudioDevicesState },
+	{ readPlaylistState, savePlaylistState },
+};
+
+static const char *sfpath = NULL;
+
+static void get_state_file_path(void)
+{
+	ConfigParam *param;
+	if (sfpath)
+		return;
+	param = parseConfigFilePath(CONF_STATE_FILE, 0);
+	if (param)
+		sfpath = (const char *)param->value;
+}
+
+void write_state_file(void)
+{
+	int i;
+	FILE *fp;
+
+	if (!sfpath)
+		return;
+	while (!(fp = fopen(sfpath, "w")) && errno == EINTR);
+
+	if (mpd_unlikely(!fp)) {
+		ERROR("problems opening state file \"%s\" for writing: %s\n",
+		      sfpath, strerror(errno));
+		return;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(sf_callbacks); i++)
+		sf_callbacks[i].writer(fp);
+
+	while(fclose(fp) && errno == EINTR) /* nothing */;
+}
+
+void read_state_file(void)
+{
+	struct stat st;
+	int i;
+	FILE *fp;
+
+	get_state_file_path();
+	if (!sfpath)
+		return;
+	if (stat(sfpath, &st) < 0) {
+		DEBUG("failed to stat state file: %s\n", sfpath);
+		return;
+	}
+	if (!S_ISREG(st.st_mode)) {
+		ERROR("state file \"%s\" is not a regular file\n", sfpath);
+		exit(EXIT_FAILURE);
+	}
+
+	while (!(fp = fopen(sfpath, "r")) && errno == EINTR);
+	if (mpd_unlikely(!fp)) {
+		ERROR("problems opening state file \"%s\" for reading: %s\n",
+		      sfpath, strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+	for (i = 0; i < ARRAY_SIZE(sf_callbacks); i++) {
+		sf_callbacks[i].reader(fp);
+		rewind(fp);
+	}
+
+	while(fclose(fp) && errno == EINTR) /* nothing */;
+}
+
+void mpd_noreturn state_file_fatal(void)
+{
+	ERROR("error parsing state file \"%s\"\n", sfpath);
+	exit(EXIT_FAILURE);
+}
+
diff --git a/src/state_file.h b/src/state_file.h
new file mode 100644
index 000000000..e717fbe87
--- /dev/null
+++ b/src/state_file.h
@@ -0,0 +1,30 @@
+/* the Music Player Daemon (MPD)
+ * (c)2003-2006 by Warren Dukes (warren.dukes@gmail.com)
+ * This project's homepage is: http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef STATE_FILE_H
+#define STATE_FILE_H
+
+#include "gcc.h"
+
+#include <stdio.h>
+
+void write_state_file(void);
+void read_state_file(void);
+void mpd_noreturn state_file_fatal(void);
+
+#endif /* STATE_FILE_H */
diff --git a/src/utils.h b/src/utils.h
index bc16905ea..02f70e946 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -29,6 +29,8 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 
+#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
+
 char *myFgets(char *buffer, int bufferSize, FILE * fp);
 
 char *strDupToUpper(char *str);