X-Git-Url: http://sigrok.org/gitweb/?a=blobdiff_plain;f=serialport.c;h=fb7adf65eb0aa7efb4f9b9260d96d81d74bd2722;hb=0188a545c75b1012054efef41b8fb465ca90a37a;hp=35b6ac54fe20b067701be9d212f4d864de2e2df8;hpb=772c586133ec5e069233bac08a0bb0e86b36a6e8;p=libserialport.git

diff --git a/serialport.c b/serialport.c
index 35b6ac5..fb7adf6 100644
--- a/serialport.c
+++ b/serialport.c
@@ -774,6 +774,7 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
 	size_t bytes_written = 0;
 	unsigned char *ptr = (unsigned char *) buf;
 	struct timeval start, delta, now, end = {0, 0};
+	int started = 0;
 	fd_set fds;
 	int result;
 
@@ -792,16 +793,20 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
 
 	/* Loop until we have written the requested number of bytes. */
 	while (bytes_written < count) {
-		/* Wait until space is available. */
-		if (timeout_ms) {
+		/*
+		 * Check timeout only if we have run select() at least once,
+		 * to avoid any issues if a short timeout is reached before
+		 * select() is even run.
+		 */
+		if (timeout_ms && started) {
 			gettimeofday(&now, NULL);
-			if (timercmp(&now, &end, >)) {
-				DEBUG("Write timed out");
-				RETURN_INT(bytes_written);
-			}
+			if (timercmp(&now, &end, >))
+				/* Timeout has expired. */
+				break;
 			timersub(&end, &now, &delta);
 		}
 		result = select(port->fd + 1, NULL, &fds, NULL, timeout_ms ? &delta : NULL);
+		started = 1;
 		if (result < 0) {
 			if (errno == EINTR) {
 				DEBUG("select() call was interrupted, repeating");
@@ -810,8 +815,8 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
 				RETURN_FAIL("select() failed");
 			}
 		} else if (result == 0) {
-			DEBUG("Write timed out");
-			RETURN_INT(bytes_written);
+			/* Timeout has expired. */
+			break;
 		}
 
 		/* Do write. */
@@ -830,6 +835,9 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
 		ptr += result;
 	}
 
+	if (bytes_written < count)
+		DEBUG("Write timed out");
+
 	RETURN_INT(bytes_written);
 #endif
 }
@@ -962,8 +970,10 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 
 	/* Set timeout. */
 	if (port->timeouts.ReadIntervalTimeout != 0 ||
+			port->timeouts.ReadTotalTimeoutMultiplier != 0 ||
 			port->timeouts.ReadTotalTimeoutConstant != timeout_ms) {
 		port->timeouts.ReadIntervalTimeout = 0;
+		port->timeouts.ReadTotalTimeoutMultiplier = 0;
 		port->timeouts.ReadTotalTimeoutConstant = timeout_ms;
 		if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
 			RETURN_FAIL("SetCommTimeouts() failed");
@@ -990,6 +1000,7 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 	size_t bytes_read = 0;
 	unsigned char *ptr = (unsigned char *) buf;
 	struct timeval start, delta, now, end = {0, 0};
+	int started = 0;
 	fd_set fds;
 	int result;
 
@@ -1008,15 +1019,20 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 
 	/* Loop until we have the requested number of bytes. */
 	while (bytes_read < count) {
-		/* Wait until data is available. */
-		if (timeout_ms) {
+		/*
+		 * Check timeout only if we have run select() at least once,
+		 * to avoid any issues if a short timeout is reached before
+		 * select() is even run.
+		 */
+		if (timeout_ms && started) {
 			gettimeofday(&now, NULL);
 			if (timercmp(&now, &end, >))
 				/* Timeout has expired. */
-				RETURN_INT(bytes_read);
+				break;
 			timersub(&end, &now, &delta);
 		}
 		result = select(port->fd + 1, &fds, NULL, NULL, timeout_ms ? &delta : NULL);
+		started = 1;
 		if (result < 0) {
 			if (errno == EINTR) {
 				DEBUG("select() call was interrupted, repeating");
@@ -1025,8 +1041,8 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 				RETURN_FAIL("select() failed");
 			}
 		} else if (result == 0) {
-			DEBUG("Read timed out");
-			RETURN_INT(bytes_read);
+			/* Timeout has expired. */
+			break;
 		}
 
 		/* Do read. */
@@ -1034,7 +1050,10 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 
 		if (result < 0) {
 			if (errno == EAGAIN)
-				/* This shouldn't happen because we did a select() first, but handle anyway. */
+				/*
+				 * This shouldn't happen because we did a
+				 * select() first, but handle anyway.
+				 */
 				continue;
 			else
 				/* This is an actual failure. */
@@ -1045,6 +1064,9 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 		ptr += result;
 	}
 
+	if (bytes_read < count)
+		DEBUG("Read timed out");
+
 	RETURN_INT(bytes_read);
 #endif
 }
@@ -1066,8 +1088,10 @@ SP_API enum sp_return sp_nonblocking_read(struct sp_port *port, void *buf,
 
 	/* Set timeout. */
 	if (port->timeouts.ReadIntervalTimeout != MAXDWORD ||
+			port->timeouts.ReadTotalTimeoutMultiplier != 0 ||
 			port->timeouts.ReadTotalTimeoutConstant != 0) {
 		port->timeouts.ReadIntervalTimeout = MAXDWORD;
+		port->timeouts.ReadTotalTimeoutMultiplier = 0;
 		port->timeouts.ReadTotalTimeoutConstant = 0;
 		if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
 			RETURN_FAIL("SetCommTimeouts() failed");
@@ -1262,6 +1286,7 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
 	RETURN_OK();
 #else
 	struct timeval start, delta, now, end = {0, 0};
+	int started = 0;
 	int result, timeout_remaining_ms;
 	struct pollfd *pollfds;
 	unsigned int i;
@@ -1293,7 +1318,12 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
 
 	/* Loop until an event occurs. */
 	while (1) {
-		if (timeout_ms) {
+		/*
+		 * Check timeout only if we have run poll() at least once,
+		 * to avoid any issues if a short timeout is reached before
+		 * poll() is even run.
+		 */
+		if (timeout_ms && started) {
 			gettimeofday(&now, NULL);
 			if (timercmp(&now, &end, >)) {
 				DEBUG("Wait timed out");
@@ -1304,6 +1334,7 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
 		}
 
 		result = poll(pollfds, event_set->count, timeout_ms ? timeout_remaining_ms : -1);
+		started = 1;
 
 		if (result < 0) {
 			if (errno == EINTR) {