First steps in make signals more abstract from the underlying mechanism; replace epoll with poll.

We now don't assume that a signal equals a single fd (eventfd on Linux).
The next step would be to create a version of signal.c that uses a pipe
internally, so it can be used on other platforms, like *BSD.

This is also the reason epoll was replaced with poll in uplink.c

3 files changed, 13 insertions, 12 deletions

diff --git a/src/fuse/connection.c b/src/fuse/connection.c
index 170e329..65483a5 100644
--- a/src/fuse/connection.c
+++ b/src/fuse/connection.c
@@ -46,7 +46,7 @@ static struct {
 static struct {
 	int sockFd;
 	pthread_mutex_t sendMutex;
-	int panicSignalFd;
+	dnbd3_signal_t* panicSignal;
 	dnbd3_host_t currentServer;
 	uint64_t startupTime;
 } connection;
@@ -134,7 +134,7 @@ bool connection_init(const char *hosts, const char *lowerImage, const uint16_t r
 				image.rid = remoteRid;
 				image.size = remoteSize;
 				connection.currentServer = altservers[i].host;
-				connection.panicSignalFd = signal_new();
+				connection.panicSignal = signal_new();
 				connection.startupTime = nowMilli();
 				connection.sockFd = sock;
 				requests.head = NULL;
@@ -205,7 +205,7 @@ bool connection_read(dnbd3_async_t *request)
 			shutdown( connection.sockFd, SHUT_RDWR );
 			connection.sockFd = -1;
 			pthread_mutex_unlock( &connection.sendMutex );
-			signal_call( connection.panicSignalFd );
+			signal_call( connection.panicSignal );
 			return true;
 		}
 	}
@@ -316,7 +316,7 @@ static void* connection_receiveThreadMain(void *sockPtr)
 				// Success, wake up caller
 				request->success = true;
 				request->finished = true;
-				signal_call( request->signalFd );
+				signal_call( request->signal );
 			}
 		} else if ( reply.cmd == CMD_GET_SERVERS ) {
 			// List of known alt servers
@@ -348,7 +348,7 @@ fail:;
 	logadd( LOG_DEBUG1, "RT: Local sock: %d, global: %d", sockFd, connection.sockFd );
 	if ( connection.sockFd == sockFd ) {
 		connection.sockFd = -1;
-		signal_call( connection.panicSignalFd );
+		signal_call( connection.panicSignal );
 	}
 	pthread_mutex_unlock( &connection.sendMutex );
 	// As we're the only reader, it's safe to close the socket now
@@ -365,7 +365,7 @@ static void* connection_backgroundThread(void *something UNUSED)
 		const uint64_t now = nowMilli();
 		if ( now < nextKeepalive && now < nextRttCheck ) {
 			int waitTime = (int)( MIN( nextKeepalive, nextRttCheck ) - now );
-			int waitRes = signal_wait( connection.panicSignalFd, waitTime );
+			int waitRes = signal_wait( connection.panicSignal, waitTime );
 			if ( waitRes == SIGNAL_ERROR ) {
 				logadd( LOG_WARNING, "Error waiting on signal in background thread! Errno = %d", errno );
 			}
@@ -585,7 +585,7 @@ static void switchConnection(int sockFd, alt_server_t *srv)
 	if ( ret != 0 ) {
 		close( sockFd );
 		logadd( LOG_WARNING, "Could not getpeername after connection switch, assuming connection already dead again. (Errno=%d)", errno );
-		signal_call( connection.panicSignalFd );
+		signal_call( connection.panicSignal );
 		return;
 	}
 	connection.startupTime = nowMilli();
@@ -604,7 +604,7 @@ static void switchConnection(int sockFd, alt_server_t *srv)
 				logadd( LOG_WARNING, "Resending pending request failed, re-entering panic mode" );
 				shutdown( connection.sockFd, SHUT_RDWR );
 				connection.sockFd = -1;
-				signal_call( connection.panicSignalFd );
+				signal_call( connection.panicSignal );
 			}
 		}
 		pthread_mutex_unlock( &connection.sendMutex );
diff --git a/src/fuse/connection.h b/src/fuse/connection.h
index 06db6c4..f01577d 100644
--- a/src/fuse/connection.h
+++ b/src/fuse/connection.h
@@ -1,6 +1,7 @@
 #ifndef _CONNECTION_H_
 #define _CONNECTION_H_
 
+#include "../shared/signal.h"
 #include <stdbool.h>
 #include <stdint.h>
 
@@ -11,7 +12,7 @@ typedef struct _dnbd3_async {
 	char* buffer;      // Caller-provided buffer to be filled
 	uint64_t offset;
 	uint32_t length;
-	int signalFd;      // Used to signal the caller
+	dnbd3_signal_t* signal; // Used to signal the caller
 	bool finished;     // Will be set to true if the request has been handled
 	bool success;      // Will be set to true if the request succeeded
 } dnbd3_async_t;
diff --git a/src/fuse/main.c b/src/fuse/main.c
index 22c400e..cf35596 100644
--- a/src/fuse/main.c
+++ b/src/fuse/main.c
@@ -136,13 +136,13 @@ static int image_read(const char *path, char *buf, size_t size, off_t offset, st
 	request.buffer = buf;
 	request.length = (uint32_t)size;
 	request.offset = offset;
-	request.signalFd = signal_newBlocking();
+	request.signal = signal_newBlocking();
 
 	if ( !connection_read( &request ) ) {
 		return -EINVAL;
 	}
 	while ( !request.finished ) {
-		int ret = signal_wait( request.signalFd, 5000 );
+		int ret = signal_wait( request.signal, 5000 );
 		if ( !keepRunning ) {
 			connection_close();
 			break;
@@ -151,7 +151,7 @@ static int image_read(const char *path, char *buf, size_t size, off_t offset, st
 			debugf( "fuse_read signal wait returned %d", ret );
 		}
 	}
-	signal_close( request.signalFd );
+	signal_close( request.signal );
 	if ( request.success ) {
 		return request.length;
 	} else {