From 415e28e43bf0538ced45d6f0a2627448d7360ba0 Mon Sep 17 00:00:00 2001
From: Simon Rettberg
Date: Fri, 5 Feb 2016 21:14:23 +0100
Subject: [SHARED] Implement pipe() based signalling

---
 src/shared/signal.c | 81 +++++++----------------------------------------------
 1 file changed, 10 insertions(+), 71 deletions(-)

(limited to 'src/shared/signal.c')

diff --git a/src/shared/signal.c b/src/shared/signal.c
index e023c49..051f785 100644
--- a/src/shared/signal.c
+++ b/src/shared/signal.c
@@ -1,74 +1,13 @@
 #include "signal.h"
-#include <sys/eventfd.h>
-#include <poll.h>
-#include <inttypes.h>
-#include <errno.h>
-#include <unistd.h>
 
-/*
- * Linux implementation of signals.
- * Internally, eventfds are used for signalling, as they
- * provide the least overhead. We don't allocate any struct
- * ever, but cast the event fd+1 to dnbd3_signal_t*
- * to save all the malloc() and free() calls.
- */
-
-dnbd3_signal_t* signal_new()
-{
-	// On error, eventfd() returns -1, so essentially we return NULL on error.
-	// (Yes, NULL doesn't have to be 0 everywhere, but cmon)
-	return (dnbd3_signal_t*)(intptr_t)( eventfd( 0, EFD_NONBLOCK ) + 1 );
-}
-
-dnbd3_signal_t* signal_newBlocking()
-{
-	return (dnbd3_signal_t*)(intptr_t)( eventfd( 0, 0 ) + 1 );
-}
-
-int signal_call(const dnbd3_signal_t* const signal)
-{
-	if ( signal == NULL ) return SIGNAL_ERROR;
-	static uint64_t one = 1;
-	const int signalFd = ( (int)(intptr_t)signal ) - 1;
-	return write( signalFd, &one, sizeof one ) == sizeof one;
-}
-
-int signal_wait(const dnbd3_signal_t* const signal, int timeoutMs)
-{
-	if ( signal == NULL ) return SIGNAL_ERROR;
-	const int signalFd = ( (int)(intptr_t)signal ) - 1;
-	struct pollfd ps = {
-		.fd = signalFd,
-		.events = POLLIN
-	};
-	int ret = poll( &ps, 1, timeoutMs );
-	if ( ret == 0 ) return SIGNAL_TIMEOUT;
-	if ( ret == -1 ) return SIGNAL_ERROR;
-	if ( ps.revents & ( POLLERR | POLLNVAL ) ) return SIGNAL_ERROR;
-	return signal_clear( signal );
-}
-
-int signal_clear(const dnbd3_signal_t* const signal)
-{
-	if ( signal == NULL ) return SIGNAL_ERROR;
-	uint64_t ret;
-	const int signalFd = ( (int)(intptr_t)signal ) - 1;
-	if ( read( signalFd, &ret, sizeof ret ) != sizeof ret ) {
-		if ( errno == EAGAIN ) return 0;
-		return SIGNAL_ERROR;
-	}
-	return (int)ret;
-}
-
-void signal_close(const dnbd3_signal_t* const signal)
-{
-	const int signalFd = ( (int)(intptr_t)signal ) - 1;
-	close( signalFd );
-}
-
-int signal_getWaitFd(const dnbd3_signal_t* const signal)
-{
-	const int signalFd = ( (int)(intptr_t)signal ) - 1;
-	return signalFd;
-}
+#if defined(linux)
+//#warning "Using eventfd based signalling"
+#include "signal.inc/eventfd.c"
+#elif __SIZEOF_INT__ == 4 && __SIZEOF_POINTER__ == 8
+//#warning "Using pointer-packing pipe based signalling"
+#include "signal.inc/pipe64.c"
+#else
+//#warning "Using fallback pipe based signalling"
+#include "signal.inc/pipe_malloc.c"
+#endif
 
-- 
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