]> sigrok.org Git - libserialport.git/blobdiff - serialport.c
Use O_CLOEXEC where available
[libserialport.git] / serialport.c
index 449317052704e87a5f8038b0f50ea1399d097115..9e56e89aed61c1347bef3b08f867ff2344f7772e 100644 (file)
@@ -55,6 +55,28 @@ static enum sp_return get_config(struct sp_port *port, struct port_data *data,
 static enum sp_return set_config(struct sp_port *port, struct port_data *data,
        const struct sp_port_config *config);
 
+#ifndef _WIN32
+static void get_time(struct timeval *time)
+{
+#ifdef HAVE_CLOCK_GETTIME
+       struct timespec ts;
+       if (clock_gettime(CLOCK_MONOTONIC, &ts) == -1)
+               clock_gettime(CLOCK_REALTIME, &ts);
+       time->tv_sec = ts.tv_sec;
+       time->tv_usec = ts.tv_nsec / 1000;
+#elif defined(__APPLE__)
+       mach_timebase_info_data_t info;
+       mach_timebase_info(&info);
+       uint64_t ticks = mach_absolute_time();
+       uint64_t ns = (ticks * info.numer) / info.denom;
+       time->tv_sec = ns / 1000000000;
+       time->tv_usec = (ns % 1000000000) / 1000;
+#else
+       gettimeofday(time, NULL);
+#endif
+}
+#endif
+
 SP_API enum sp_return sp_get_port_by_name(const char *portname, struct sp_port **port_ptr)
 {
        struct sp_port *port;
@@ -104,6 +126,8 @@ SP_API enum sp_return sp_get_port_by_name(const char *portname, struct sp_port *
 #ifdef _WIN32
        port->usb_path = NULL;
        port->hdl = INVALID_HANDLE_VALUE;
+       port->write_buf = NULL;
+       port->write_buf_size = 0;
 #else
        port->fd = -1;
 #endif
@@ -310,6 +334,8 @@ SP_API void sp_free_port(struct sp_port *port)
 #ifdef _WIN32
        if (port->usb_path)
                free(port->usb_path);
+       if (port->write_buf)
+               free(port->write_buf);
 #endif
 
        free(port);
@@ -537,7 +563,7 @@ SP_API enum sp_return sp_open(struct sp_port *port, enum sp_mode flags)
                RETURN_CODEVAL(ret);
        }
 #else
-       int flags_local = O_NONBLOCK | O_NOCTTY;
+       int flags_local = O_NONBLOCK | O_NOCTTY | O_CLOEXEC;
 
        /* Map 'flags' to the OS-specific settings. */
        if ((flags & SP_MODE_READ_WRITE) == SP_MODE_READ_WRITE)
@@ -643,6 +669,10 @@ SP_API enum sp_return sp_close(struct sp_port *port)
        CLOSE_OVERLAPPED(write_ovl);
        CLOSE_OVERLAPPED(wait_ovl);
 
+       if (port->write_buf) {
+               free(port->write_buf);
+               port->write_buf = NULL;
+       }
 #else
        /* Returns 0 upon success, -1 upon failure. */
        if (close(port->fd) == -1)
@@ -785,6 +815,10 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
                        RETURN_FAIL("SetCommTimeouts() failed");
        }
 
+       /* Reduce count if it exceeds the WriteFile limit. */
+       if (count > WRITEFILE_MAX_SIZE)
+               count = WRITEFILE_MAX_SIZE;
+
        /* Start write. */
        if (WriteFile(port->hdl, buf, count, NULL, &port->write_ovl)) {
                DEBUG("Write completed immediately");
@@ -814,7 +848,7 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
 
        if (timeout_ms) {
                /* Get time at start of operation. */
-               gettimeofday(&start, NULL);
+               get_time(&start);
                /* Define duration of timeout. */
                delta.tv_sec = timeout_ms / 1000;
                delta.tv_usec = (timeout_ms % 1000) * 1000;
@@ -833,7 +867,7 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
                 * select() is even run.
                 */
                if (timeout_ms && started) {
-                       gettimeofday(&now, NULL);
+                       get_time(&now);
                        if (timercmp(&now, &end, >))
                                /* Timeout has expired. */
                                break;
@@ -892,8 +926,7 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
                RETURN_INT(0);
 
 #ifdef _WIN32
-       DWORD written = 0;
-       BYTE *ptr = (BYTE *) buf;
+       DWORD buf_bytes;
 
        /* Check whether previous write is complete. */
        if (port->writing) {
@@ -914,40 +947,30 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
                        RETURN_FAIL("SetCommTimeouts() failed");
        }
 
-       /*
-        * Keep writing data until the OS has to actually start an async IO
-        * for it. At that point we know the buffer is full.
-        */
-       while (written < count) {
-               /* Copy first byte of user buffer. */
-               port->pending_byte = *ptr++;
-
-               /* Start asynchronous write. */
-               if (WriteFile(port->hdl, &port->pending_byte, 1, NULL, &port->write_ovl) == 0) {
-                       if (GetLastError() == ERROR_IO_PENDING) {
-                               if (HasOverlappedIoCompleted(&port->write_ovl)) {
-                                       DEBUG("Asynchronous write completed immediately");
-                                       port->writing = 0;
-                                       written++;
-                                       continue;
-                               } else {
-                                       DEBUG("Asynchronous write running");
-                                       port->writing = 1;
-                                       RETURN_INT(++written);
-                               }
-                       } else {
-                               /* Actual failure of some kind. */
-                               RETURN_FAIL("WriteFile() failed");
-                       }
+       /* Reduce count if it exceeds the WriteFile limit. */
+       if (count > WRITEFILE_MAX_SIZE)
+               count = WRITEFILE_MAX_SIZE;
+
+       /* Copy data to our write buffer. */
+       buf_bytes = min(port->write_buf_size, count);
+       memcpy(port->write_buf, buf, buf_bytes);
+
+       /* Start asynchronous write. */
+       if (WriteFile(port->hdl, port->write_buf, buf_bytes, NULL, &port->write_ovl) == 0) {
+               if (GetLastError() == ERROR_IO_PENDING) {
+                       if ((port->writing = !HasOverlappedIoCompleted(&port->write_ovl)))
+                               DEBUG("Asynchronous write completed immediately");
+                       else
+                               DEBUG("Asynchronous write running");
                } else {
-                       DEBUG("Single byte written immediately");
-                       written++;
+                       /* Actual failure of some kind. */
+                       RETURN_FAIL("WriteFile() failed");
                }
        }
 
        DEBUG("All bytes written immediately");
 
-       RETURN_INT(written);
+       RETURN_INT(buf_bytes);
 #else
        /* Returns the number of bytes written, or -1 upon failure. */
        ssize_t written = write(port->fd, buf, count);
@@ -1045,7 +1068,7 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 
        if (timeout_ms) {
                /* Get time at start of operation. */
-               gettimeofday(&start, NULL);
+               get_time(&start);
                /* Define duration of timeout. */
                delta.tv_sec = timeout_ms / 1000;
                delta.tv_usec = (timeout_ms % 1000) * 1000;
@@ -1064,7 +1087,7 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
                 * select() is even run.
                 */
                if (timeout_ms && started) {
-                       gettimeofday(&now, NULL);
+                       get_time(&now);
                        if (timercmp(&now, &end, >))
                                /* Timeout has expired. */
                                break;
@@ -1182,7 +1205,7 @@ SP_API enum sp_return sp_blocking_read_next(struct sp_port *port, void *buf,
 
        if (timeout_ms) {
                /* Get time at start of operation. */
-               gettimeofday(&start, NULL);
+               get_time(&start);
                /* Define duration of timeout. */
                delta.tv_sec = timeout_ms / 1000;
                delta.tv_usec = (timeout_ms % 1000) * 1000;
@@ -1201,7 +1224,7 @@ SP_API enum sp_return sp_blocking_read_next(struct sp_port *port, void *buf,
                 * select() is even run.
                 */
                if (timeout_ms && started) {
-                       gettimeofday(&now, NULL);
+                       get_time(&now);
                        if (timercmp(&now, &end, >))
                                /* Timeout has expired. */
                                break;
@@ -1484,7 +1507,7 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
 
        if (timeout_ms) {
                /* Get time at start of operation. */
-               gettimeofday(&start, NULL);
+               get_time(&start);
                /* Define duration of timeout. */
                delta.tv_sec = timeout_ms / 1000;
                delta.tv_usec = (timeout_ms % 1000) * 1000;
@@ -1505,7 +1528,7 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
                        timeout_overflow = (timeout_ms > INT_MAX);
                        timeout_remaining_ms = timeout_overflow ? INT_MAX : timeout_ms;
                } else {
-                       gettimeofday(&now, NULL);
+                       get_time(&now);
                        if (timercmp(&now, &end, >)) {
                                DEBUG("Wait timed out");
                                break;
@@ -1881,6 +1904,9 @@ static enum sp_return set_config(struct sp_port *port, struct port_data *data,
        DEBUG_FMT("Setting configuration for port %s", port->name);
 
 #ifdef _WIN32
+
+       TRY(await_write_completion(port));
+
        if (config->baudrate >= 0) {
                for (i = 0; i < NUM_STD_BAUDRATES; i++) {
                        if (config->baudrate == std_baudrates[i].value) {
@@ -1891,6 +1917,14 @@ static enum sp_return set_config(struct sp_port *port, struct port_data *data,
 
                if (i == NUM_STD_BAUDRATES)
                        data->dcb.BaudRate = config->baudrate;
+
+               /* Allocate write buffer for 50ms of data at baud rate. */
+               port->write_buf_size = max(config->baudrate / (8 * 20), 1);
+               port->write_buf = realloc(port->write_buf,
+                                         port->write_buf_size);
+
+               if (!port->write_buf)
+                       RETURN_ERROR(SP_ERR_MEM, "Allocating write buffer failed");
        }
 
        if (config->bits >= 0)