Fix a potential segfault in sp_get_port_handle().

[libserialport.git] / serialport.c

diff --git a/serialport.c b/serialport.c
index 9826df45597711d4e81a6566cf81590e8128922e..80527be098a85eed8d624ce7ff8dd4e5dc594e12 100644 (file)
--- a/serialport.c
+++ b/serialport.c
@@ -126,7 +126,7 @@ SP_API char *sp_get_port_name(const struct sp_port *port)
        RETURN_STRING(port->name);
 }
 
-SP_API char *sp_get_port_description(struct sp_port *port)
+SP_API char *sp_get_port_description(const struct sp_port *port)
 {
        TRACE("%p", port);
 
@@ -136,7 +136,7 @@ SP_API char *sp_get_port_description(struct sp_port *port)
        RETURN_STRING(port->description);
 }
 
-SP_API enum sp_transport sp_get_port_transport(struct sp_port *port)
+SP_API enum sp_transport sp_get_port_transport(const struct sp_port *port)
 {
        TRACE("%p", port);
 
@@ -234,6 +234,8 @@ SP_API enum sp_return sp_get_port_handle(const struct sp_port *port,
 
        if (!port)
                RETURN_ERROR(SP_ERR_ARG, "Null port");
+       if (!result_ptr)
+               RETURN_ERROR(SP_ERR_ARG, "Null result pointer");
 
 #ifdef _WIN32
        HANDLE *handle_ptr = result_ptr;
@@ -713,18 +715,18 @@ SP_API enum sp_return sp_drain(struct sp_port *port)
 }
 
 SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
-                                        size_t count, unsigned int timeout)
+                                        size_t count, unsigned int timeout_ms)
 {
-       TRACE("%p, %p, %d, %d", port, buf, count, timeout);
+       TRACE("%p, %p, %d, %d", port, buf, count, timeout_ms);
 
        CHECK_OPEN_PORT();
 
        if (!buf)
                RETURN_ERROR(SP_ERR_ARG, "Null buffer");
 
-       if (timeout)
+       if (timeout_ms)
                DEBUG_FMT("Writing %d bytes to port %s, timeout %d ms",
-                       count, port->name, timeout);
+                       count, port->name, timeout_ms);
        else
                DEBUG_FMT("Writing %d bytes to port %s, no timeout",
                        count, port->name);
@@ -747,7 +749,7 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
        }
 
        /* Set timeout. */
-       port->timeouts.WriteTotalTimeoutConstant = timeout;
+       port->timeouts.WriteTotalTimeoutConstant = timeout_ms;
        if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
                RETURN_FAIL("SetCommTimeouts() failed");
 
@@ -772,12 +774,12 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
        fd_set fds;
        int result;
 
-       if (timeout) {
+       if (timeout_ms) {
                /* Get time at start of operation. */
                gettimeofday(&start, NULL);
                /* Define duration of timeout. */
-               delta.tv_sec = timeout / 1000;
-               delta.tv_usec = (timeout % 1000) * 1000;
+               delta.tv_sec = timeout_ms / 1000;
+               delta.tv_usec = (timeout_ms % 1000) * 1000;
                /* Calculate time at which we should give up. */
                timeradd(&start, &delta, &end);
        }
@@ -787,7 +789,7 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
                /* Wait until space is available. */
                FD_ZERO(&fds);
                FD_SET(port->fd, &fds);
-               if (timeout) {
+               if (timeout_ms) {
                        gettimeofday(&now, NULL);
                        if (timercmp(&now, &end, >)) {
                                DEBUG("Write timed out");
@@ -795,7 +797,7 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
                        }
                        timersub(&end, &now, &delta);
                }
-               result = select(port->fd + 1, NULL, &fds, NULL, timeout ? &delta : NULL);
+               result = select(port->fd + 1, NULL, &fds, NULL, timeout_ms ? &delta : NULL);
                if (result < 0) {
                        if (errno == EINTR) {
                                DEBUG("select() call was interrupted, repeating");
@@ -910,18 +912,18 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
 }
 
 SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
-                                       size_t count, unsigned int timeout)
+                                       size_t count, unsigned int timeout_ms)
 {
-       TRACE("%p, %p, %d, %d", port, buf, count, timeout);
+       TRACE("%p, %p, %d, %d", port, buf, count, timeout_ms);
 
        CHECK_OPEN_PORT();
 
        if (!buf)
                RETURN_ERROR(SP_ERR_ARG, "Null buffer");
 
-       if (timeout)
+       if (timeout_ms)
                DEBUG_FMT("Reading %d bytes from port %s, timeout %d ms",
-                       count, port->name, timeout);
+                       count, port->name, timeout_ms);
        else
                DEBUG_FMT("Reading %d bytes from port %s, no timeout",
                        count, port->name);
@@ -936,7 +938,7 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 
        /* Set timeout. */
        port->timeouts.ReadIntervalTimeout = 0;
-       port->timeouts.ReadTotalTimeoutConstant = timeout;
+       port->timeouts.ReadTotalTimeoutConstant = timeout_ms;
        if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
                RETURN_FAIL("SetCommTimeouts() failed");
 
@@ -974,12 +976,12 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
        fd_set fds;
        int result;
 
-       if (timeout) {
+       if (timeout_ms) {
                /* Get time at start of operation. */
                gettimeofday(&start, NULL);
                /* Define duration of timeout. */
-               delta.tv_sec = timeout / 1000;
-               delta.tv_usec = (timeout % 1000) * 1000;
+               delta.tv_sec = timeout_ms / 1000;
+               delta.tv_usec = (timeout_ms % 1000) * 1000;
                /* Calculate time at which we should give up. */
                timeradd(&start, &delta, &end);
        }
@@ -989,14 +991,14 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
                /* Wait until data is available. */
                FD_ZERO(&fds);
                FD_SET(port->fd, &fds);
-               if (timeout) {
+               if (timeout_ms) {
                        gettimeofday(&now, NULL);
                        if (timercmp(&now, &end, >))
                                /* Timeout has expired. */
                                RETURN_INT(bytes_read);
                        timersub(&end, &now, &delta);
                }
-               result = select(port->fd + 1, &fds, NULL, NULL, timeout ? &delta : NULL);
+               result = select(port->fd + 1, &fds, NULL, NULL, timeout_ms ? &delta : NULL);
                if (result < 0) {
                        if (errno == EINTR) {
                                DEBUG("select() call was interrupted, repeating");
@@ -1235,22 +1237,22 @@ SP_API void sp_free_event_set(struct sp_event_set *event_set)
 }
 
 SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
-                              unsigned int timeout)
+                              unsigned int timeout_ms)
 {
-       TRACE("%p, %d", event_set, timeout);
+       TRACE("%p, %d", event_set, timeout_ms);
 
        if (!event_set)
                RETURN_ERROR(SP_ERR_ARG, "Null event set");
 
 #ifdef _WIN32
        if (WaitForMultipleObjects(event_set->count, event_set->handles, FALSE,
-                       timeout ? timeout : INFINITE) == WAIT_FAILED)
+                       timeout_ms ? timeout_ms : INFINITE) == WAIT_FAILED)
                RETURN_FAIL("WaitForMultipleObjects() failed");
 
        RETURN_OK();
 #else
        struct timeval start, delta, now, end = {0, 0};
-       int result, timeout_remaining;
+       int result, timeout_remaining_ms;
        struct pollfd *pollfds;
        unsigned int i;
 
@@ -1269,29 +1271,29 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
                        pollfds[i].events |= POLLERR;
        }
 
-       if (timeout) {
+       if (timeout_ms) {
                /* Get time at start of operation. */
                gettimeofday(&start, NULL);
                /* Define duration of timeout. */
-               delta.tv_sec = timeout / 1000;
-               delta.tv_usec = (timeout % 1000) * 1000;
+               delta.tv_sec = timeout_ms / 1000;
+               delta.tv_usec = (timeout_ms % 1000) * 1000;
                /* Calculate time at which we should give up. */
                timeradd(&start, &delta, &end);
        }
 
        /* Loop until an event occurs. */
        while (1) {
-               if (timeout) {
+               if (timeout_ms) {
                        gettimeofday(&now, NULL);
                        if (timercmp(&now, &end, >)) {
                                DEBUG("Wait timed out");
                                break;
                        }
                        timersub(&end, &now, &delta);
-                       timeout_remaining = delta.tv_sec * 1000 + delta.tv_usec / 1000;
+                       timeout_remaining_ms = delta.tv_sec * 1000 + delta.tv_usec / 1000;
                }
 
-               result = poll(pollfds, event_set->count, timeout ? timeout_remaining : -1);
+               result = poll(pollfds, event_set->count, timeout_ms ? timeout_remaining_ms : -1);
 
                if (result < 0) {
                        if (errno == EINTR) {