optimized read() on clients, should be much, much faster now

TODO

@@ -34,8 +34,6 @@
 
 *) Cleanup Config File Code
 
-*) Optimize read() on clients
-
 *) Handle mp1 and mp2 files (including mp2's that are disguised as mp3's with 
 	a mp3 suffix)
 

src/command.c

@@ -83,9 +83,9 @@
 #define COMMAND_URL_HANDLERS   	"urlhandlers" 
 #define COMMAND_PLCHANGES	"plchanges" 
 #define COMMAND_CURRENTSONG	"currentsong" 
-#define COMMAND_ENABLE_DEV	"enabledevice"
-#define COMMAND_DISABLE_DEV	"disabledevice"
-#define COMMAND_DEVICES		"devices"
+#define COMMAND_ENABLE_DEV	"enableoutput"
+#define COMMAND_DISABLE_DEV	"disableoutput"
+#define COMMAND_DEVICES		"outputs"
 #define COMMAND_COMMANDS	"commands"
 
 #define COMMAND_STATUS_VOLUME           "volume"

src/interface.c

@@ -62,8 +62,9 @@ static size_t interface_max_output_buffer_size =
 		INTERFACE_MAX_OUTPUT_BUFFER_SIZE_DEFAULT;
 
 typedef struct _Interface {
-	char buffer[INTERFACE_MAX_BUFFER_LENGTH+2];
+	char buffer[INTERFACE_MAX_BUFFER_LENGTH];
 	int bufferLength;
+	int bufferPos;
 	int fd; /* file descriptor */
 	FILE * fp; /* file pointer */
 	int open; /* open/used */
@@ -94,6 +95,7 @@ void openInterface(Interface * interface, int fd) {
 	assert(interface->open==0);
 
 	interface->bufferLength = 0;
+	interface->bufferPos = 0;
 	interface->fd = fd;
 	/* fcntl(interface->fd,F_SETOWN,(int)getpid()); */
 	while((flags = fcntl(fd,F_GETFL))<0 && errno==EINTR);
@@ -200,39 +202,18 @@ void openAInterface(int fd, struct sockaddr * addr) {
 	}
 }
 
-int interfaceReadInput(Interface * interface) {
-	blockSignals();
-	if(read(interface->fd,interface->buffer+interface->bufferLength,1)>0) {
+static int proccessLineOfInput(Interface * interface) {
 	int ret = 1;
-		int bytesRead = 1;
-		while(bytesRead>0) {
-			interface->buffer[interface->bufferLength+1] = '\0';
-			if(interface->buffer[interface->bufferLength]!='\r') {
-				interface->bufferLength++;
-			}
-			if(interface->bufferLength>=INTERFACE_MAX_BUFFER_LENGTH) {
-				break;
-			}
-			if(interface->buffer[interface->bufferLength-1]=='\n') {
-				break;
-			}
-			bytesRead = read(interface->fd,interface->buffer+
-						interface->bufferLength,1);
+	char * line = interface->buffer+interface->bufferPos;
+
+	if(interface->bufferLength - interface->bufferPos > 1) {
+		if(interface->buffer[interface->bufferLength-2] == '\r') {
+			interface->buffer[interface->bufferLength-2] = '\0';
 		}
-		unblockSignals();
-		if(interface->bufferLength>=INTERFACE_MAX_BUFFER_LENGTH) {
-			ERROR("interface %i: buffer overflow\n",
-				interface->num);
-			closeInterface(interface);
 	}
-		else if(interface->buffer[interface->bufferLength-1]=='\n') {
-			interface->buffer[interface->bufferLength-1] = '\0';
-			interface->bufferLength = 0;
 
 	if(interface->commandList) {
-				if(strcmp(interface->buffer,
-						INTERFACE_LIST_MODE_END)==0) 
-				{
+		if(strcmp(line, INTERFACE_LIST_MODE_END)==0) {
 			DEBUG("interface %i: process command "
 					"list\n",interface->num);
 			ret = proccessListOfCommands(
@@ -245,11 +226,10 @@ int interfaceReadInput(Interface * interface) {
 					"list returned %i\n",
 					interface->num,
 					ret);
-					if(ret==0) {
-						commandSuccess(interface->fp);
-					}
-					else if(ret==COMMAND_RETURN_CLOSE ||
-							interface->expired) {
+			if(ret==0) commandSuccess(interface->fp);
+			else if(ret==COMMAND_RETURN_CLOSE || interface->expired)
+			{
+						
 				closeInterface(interface);
 			}
 			printInterfaceOutBuffer(interface);
@@ -258,10 +238,8 @@ int interfaceReadInput(Interface * interface) {
 			interface->commandList = NULL;
 		}
 		else {
-					interface->commandListSize+=
-						sizeof(ListNode);
-					interface->commandListSize+=
-						strlen(interface->buffer)+1;
+			interface->commandListSize+= sizeof(ListNode);
+			interface->commandListSize+= strlen(line)+1;
 			if(interface->commandListSize > 
 					interface_max_command_list_size)
 			{
@@ -272,66 +250,87 @@ int interfaceReadInput(Interface * interface) {
 						interface->num,
 						interface->
 						commandListSize,
-							interface_max_command_list_size);
+						interface_max_command_list_size)
+					;
 				closeInterface(interface);
-						
 			}
 			else {
-						insertInListWithoutKey(
-							interface->commandList,
-							strdup(interface->
-							buffer));
+				insertInListWithoutKey(interface->commandList,
+						strdup(line));
 			}
 		}
 	}
 	else {
-				if(strcmp(interface->buffer,
-						INTERFACE_LIST_MODE_BEGIN)==0) 
-				{
-					interface->commandList = makeList(free,
-									1);
-					interface->commandListSize = 
-						sizeof(List);
+		if(strcmp(line, INTERFACE_LIST_MODE_BEGIN) == 0) {
+			interface->commandList = makeList(free, 1);
+			interface->commandListSize = sizeof(List);
                         interface->commandListOK = 0;
 			ret = 1;
 		}
-				else if(strcmp(interface->buffer,
-						INTERFACE_LIST_OK_MODE_BEGIN)
-                                                ==0) 
-				{
-					interface->commandList = makeList(free,
-									1);
-					interface->commandListSize = 
-						sizeof(List);
+		else if(strcmp(line, INTERFACE_LIST_OK_MODE_BEGIN) == 0) {
+			interface->commandList = makeList(free, 1);
+			interface->commandListSize = sizeof(List);
                         interface->commandListOK = 1;
 			ret = 1;
 		}
 		else {
-					DEBUG("interface %i: process command \"%s\"\n",interface->num,interface->buffer);
-					ret = processCommand(
-							interface->fp,
-							&(interface->
-								permission),
-							interface->buffer);
-					DEBUG("interface %i: command returned %i\n",interface->num,ret);
-					if(ret==0) {
-						commandSuccess(interface->fp);
-					}
-					else if(ret==COMMAND_RETURN_CLOSE ||
-							interface->expired) {
+			DEBUG("interface %i: process command \"%s\"\n",
+					interface->num, line);
+			ret = processCommand(interface->fp,
+						&(interface->permission),
+						line);
+			DEBUG("interface %i: command returned %i\n",
+						interface->num, ret);
+			if(ret==0) commandSuccess(interface->fp);
+			else if(ret==COMMAND_RETURN_CLOSE || interface->expired)
+			{
 				closeInterface(interface);
 			}
 			printInterfaceOutBuffer(interface);
 		}
 	}
-		}
+
 	return ret;
+}
+
+static int processBytesRead(Interface * interface, int bytesRead) {
+	int ret = 1;
+
+	while(bytesRead > 0) {
+		interface->bufferLength++;
+		bytesRead--;
+		if(interface->buffer[interface->bufferLength-1]=='\n') {
+			interface->buffer[interface->bufferLength-1] = '\0';
+			ret = proccessLineOfInput(interface);
+			interface->bufferPos = interface->bufferLength;
+		}
+		if(interface->bufferLength==INTERFACE_MAX_BUFFER_LENGTH)
+		{
+			if(interface->bufferPos == 0) {
+				ERROR("interface %i: buffer overflow\n",
+						interface->num);
+				return 1;
+			}
+			interface->bufferLength-= interface->bufferPos;
+			memmove(interface->buffer, 
+					interface->buffer+interface->bufferPos,
+					interface->bufferLength);
+			interface->bufferPos = 0;
 		}
-	else {
-		unblockSignals();
-		closeInterface(interface);
 	}
 
+	return 0;
+}
+
+int interfaceReadInput(Interface * interface) {
+	int bytesRead = read(interface->fd, 
+			interface->buffer+interface->bufferLength, 
+			INTERFACE_MAX_BUFFER_LENGTH-interface->bufferLength+1);
+	
+	if(bytesRead > 0) return processBytesRead(interface, bytesRead);
+	else if(bytesRead == 0 && errno!=EINTR) closeInterface(interface);
+	else return 0;
+
 	return 1;
 }