]> sigrok.org Git - libserialport.git/blobdiff - serialport.c
windows: Always check return value of GetOverlappedResult().
[libserialport.git] / serialport.c
index b8ddffe870e1e1fa4c2269471d78a6cbfb185195..39500f8f93fa699e17c5b13bf6292551ae388198 100644 (file)
@@ -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;
@@ -322,14 +324,18 @@ fail:
 
 SP_API enum sp_return sp_list_ports(struct sp_port ***list_ptr)
 {
+#ifndef NO_ENUMERATION
        struct sp_port **list;
        int ret;
+#endif
 
        TRACE("%p", list_ptr);
 
        if (!list_ptr)
                RETURN_ERROR(SP_ERR_ARG, "Null result pointer");
 
+       *list_ptr = NULL;
+
 #ifdef NO_ENUMERATION
        RETURN_ERROR(SP_ERR_SUPP, "Enumeration not supported on this platform");
 #else
@@ -711,18 +717,18 @@ 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);
@@ -745,23 +751,24 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
        }
 
        /* Set timeout. */
-       port->timeouts.WriteTotalTimeoutConstant = timeout;
-       if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
-               RETURN_FAIL("SetCommTimeouts() failed");
+       if (port->timeouts.WriteTotalTimeoutConstant != timeout_ms) {
+               port->timeouts.WriteTotalTimeoutConstant = timeout_ms;
+               if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+                       RETURN_FAIL("SetCommTimeouts() failed");
+       }
 
        /* Start write. */
-       if (WriteFile(port->hdl, buf, count, NULL, &port->write_ovl) == 0) {
-               if (GetLastError() == ERROR_IO_PENDING) {
-                       DEBUG("Waiting for write to complete");
-                       GetOverlappedResult(port->hdl, &port->write_ovl, &bytes_written, TRUE);
-                       DEBUG_FMT("Write completed, %d/%d bytes written", bytes_written, count);
-                       RETURN_INT(bytes_written);
-               } else {
-                       RETURN_FAIL("WriteFile() failed");
-               }
-       } else {
+       if (WriteFile(port->hdl, buf, count, NULL, &port->write_ovl)) {
                DEBUG("Write completed immediately");
                RETURN_INT(count);
+       } else if (GetLastError() == ERROR_IO_PENDING) {
+               DEBUG("Waiting for write to complete");
+               if (GetOverlappedResult(port->hdl, &port->write_ovl, &bytes_written, TRUE) == 0)
+                       RETURN_FAIL("GetOverlappedResult() failed");
+               DEBUG_FMT("Write completed, %d/%d bytes written", bytes_written, count);
+               RETURN_INT(bytes_written);
+       } else {
+               RETURN_FAIL("WriteFile() failed");
        }
 #else
        size_t bytes_written = 0;
@@ -770,12 +777,12 @@ 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);
        }
@@ -785,7 +792,7 @@ 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");
@@ -793,7 +800,7 @@ 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");
@@ -858,9 +865,11 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
        }
 
        /* Set timeout. */
-       port->timeouts.WriteTotalTimeoutConstant = 0;
-       if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
-               RETURN_FAIL("SetCommTimeouts() failed");
+       if (port->timeouts.WriteTotalTimeoutConstant != 0) {
+               port->timeouts.WriteTotalTimeoutConstant = 0;
+               if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+                       RETURN_FAIL("SetCommTimeouts() failed");
+       }
 
        /*
         * Keep writing data until the OS has to actually start an async IO
@@ -907,19 +916,39 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
 #endif
 }
 
+#ifdef _WIN32
+/* Restart wait operation if buffer was emptied. */
+static enum sp_return restart_wait_if_needed(struct sp_port *port, unsigned int bytes_read)
+{
+       DWORD errors;
+       COMSTAT comstat;
+
+       if (bytes_read == 0)
+               RETURN_OK();
+
+       if (ClearCommError(port->hdl, &errors, &comstat) == 0)
+               RETURN_FAIL("ClearCommError() failed");
+
+       if (comstat.cbInQue == 0)
+               TRY(restart_wait(port));
+
+       RETURN_OK();
+}
+#endif
+
 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);
@@ -929,39 +958,30 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 
 #ifdef _WIN32
        DWORD bytes_read = 0;
-       DWORD bytes_remaining;
-       int ret;
 
        /* Set timeout. */
-       port->timeouts.ReadIntervalTimeout = 0;
-       port->timeouts.ReadTotalTimeoutConstant = timeout;
-       if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
-               RETURN_FAIL("SetCommTimeouts() failed");
+       if (port->timeouts.ReadIntervalTimeout != 0 ||
+                       port->timeouts.ReadTotalTimeoutConstant != timeout_ms) {
+               port->timeouts.ReadIntervalTimeout = 0;
+               port->timeouts.ReadTotalTimeoutConstant = timeout_ms;
+               if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+                       RETURN_FAIL("SetCommTimeouts() failed");
+       }
 
        /* Start read. */
-       if (ReadFile(port->hdl, buf, count, NULL, &port->read_ovl) == 0) {
-               if (GetLastError() == ERROR_IO_PENDING) {
-                       DEBUG("Waiting for read to complete");
-                       GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE);
-                       DEBUG_FMT("Read completed, %d/%d bytes read", bytes_read, count);
-               } else {
-                       RETURN_FAIL("ReadFile() failed");
-               }
-       } else {
+       if (ReadFile(port->hdl, buf, count, NULL, &port->read_ovl)) {
                DEBUG("Read completed immediately");
                bytes_read = count;
+       } else if (GetLastError() == ERROR_IO_PENDING) {
+               DEBUG("Waiting for read to complete");
+               if (GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE) == 0)
+                       RETURN_FAIL("GetOverlappedResult() failed");
+               DEBUG_FMT("Read completed, %d/%d bytes read", bytes_read, count);
+       } else {
+               RETURN_FAIL("ReadFile() failed");
        }
 
-       ret = sp_input_waiting(port);
-
-       if (ret < 0)
-               RETURN_CODEVAL(ret);
-
-       bytes_remaining = ret;
-
-       /* Restart wait operation if buffer was emptied. */
-       if (bytes_read > 0 && bytes_remaining == 0)
-               TRY(restart_wait(port));
+       TRY(restart_wait_if_needed(port, bytes_read));
 
        RETURN_INT(bytes_read);
 
@@ -972,12 +992,12 @@ 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);
        }
@@ -987,14 +1007,14 @@ 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");
@@ -1041,14 +1061,15 @@ SP_API enum sp_return sp_nonblocking_read(struct sp_port *port, void *buf,
 
 #ifdef _WIN32
        DWORD bytes_read;
-       DWORD bytes_remaining;
-       int ret;
 
        /* Set timeout. */
-       port->timeouts.ReadIntervalTimeout = MAXDWORD;
-       port->timeouts.ReadTotalTimeoutConstant = 0;
-       if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
-               RETURN_FAIL("SetCommTimeouts() failed");
+       if (port->timeouts.ReadIntervalTimeout != MAXDWORD ||
+                       port->timeouts.ReadTotalTimeoutConstant != 0) {
+               port->timeouts.ReadIntervalTimeout = MAXDWORD;
+               port->timeouts.ReadTotalTimeoutConstant = 0;
+               if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+                       RETURN_FAIL("SetCommTimeouts() failed");
+       }
 
        /* Do read. */
        if (ReadFile(port->hdl, buf, count, NULL, &port->read_ovl) == 0)
@@ -1058,16 +1079,7 @@ SP_API enum sp_return sp_nonblocking_read(struct sp_port *port, void *buf,
        if (GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE) == 0)
                RETURN_FAIL("GetOverlappedResult() failed");
 
-       ret = sp_input_waiting(port);
-
-       if (ret < 0)
-               RETURN_CODEVAL(ret);
-
-       bytes_remaining = ret;
-
-       /* Restart wait operation if buffer was emptied. */
-       if (bytes_read > 0 && bytes_remaining == 0)
-               TRY(restart_wait(port));
+       TRY(restart_wait_if_needed(port, bytes_read));
 
        RETURN_INT(bytes_read);
 #else
@@ -1165,11 +1177,12 @@ static enum sp_return add_handle(struct sp_event_set *event_set,
                        sizeof(event_handle) * (event_set->count + 1))))
                RETURN_ERROR(SP_ERR_MEM, "Handle array realloc() failed");
 
+       event_set->handles = new_handles;
+
        if (!(new_masks = realloc(event_set->masks,
                        sizeof(enum sp_event) * (event_set->count + 1))))
                RETURN_ERROR(SP_ERR_MEM, "Mask array realloc() failed");
 
-       event_set->handles = new_handles;
        event_set->masks = new_masks;
 
        ((event_handle *) event_set->handles)[event_set->count] = handle;
@@ -1232,22 +1245,22 @@ 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;
 
@@ -1266,29 +1279,29 @@ 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) {
@@ -2112,6 +2125,8 @@ SP_API enum sp_return sp_set_##x(struct sp_port *port, type x) { \
 SP_API enum sp_return sp_get_config_##x(const struct sp_port_config *config, \
                                         type *x) { \
        TRACE("%p, %p", config, x); \
+       if (!x) \
+               RETURN_ERROR(SP_ERR_ARG, "Null result pointer"); \
        if (!config) \
                RETURN_ERROR(SP_ERR_ARG, "Null config"); \
        *x = config->x; \
@@ -2278,10 +2293,10 @@ SP_API char *sp_last_error_message(void)
        TRACE_VOID();
 
 #ifdef _WIN32
-       LPVOID message;
+       TCHAR *message;
        DWORD error = GetLastError();
 
-       FormatMessage(
+       DWORD length = FormatMessage(
                FORMAT_MESSAGE_ALLOCATE_BUFFER |
                FORMAT_MESSAGE_FROM_SYSTEM |
                FORMAT_MESSAGE_IGNORE_INSERTS,
@@ -2291,6 +2306,9 @@ SP_API char *sp_last_error_message(void)
                (LPTSTR) &message,
                0, NULL );
 
+       if (length >= 2 && message[length - 2] == '\r')
+               message[length - 2] = '\0';
+
        RETURN_STRING(message);
 #else
        RETURN_STRING(strerror(errno));