serial: Use OS-independent flags for serial port opening.

[libsigrok.git] / hardware / common / serial.c

diff --git a/hardware/common/serial.c b/hardware/common/serial.c
index 8ab2d401402ce7ed03dd20784f138f1305b894c4..b9ef46d4cda23960e2035a571d2296a687810db9 100644 (file)
--- a/hardware/common/serial.c
+++ b/hardware/common/serial.c
@@ -55,8 +55,8 @@ static HANDLE hdl;
  * Open the specified serial port.
  *
  * @param serial Previously initialized serial port structure.
- * @param flags Flags to use when opening the serial port.
- * TODO: Abstract 'flags', currently they're OS-specific!
+ * @param flags Flags to use when opening the serial port. Possible flags
+ *              include SERIAL_RDWR, SERIAL_RDONLY, SERIAL_NONBLOCK.
  *
  * If the serial structure contains a serialcomm string, it will be
  * passed to serial_set_paramstr() after the port is opened.
@@ -65,6 +65,10 @@ static HANDLE hdl;
  */
 SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
 {
+       int flags_local = 0;
+#ifdef _WIN32
+       DWORD desired_access = 0, flags_and_attributes = 0;
+#endif
 
        if (!serial) {
                sr_dbg("Invalid serial port.");
@@ -74,19 +78,36 @@ SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
        sr_spew("Opening serial port '%s' (flags %d).", serial->port, flags);
 
 #ifdef _WIN32
-       hdl = CreateFile(serial->port, GENERIC_READ | GENERIC_WRITE, 0, 0,
-                        OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
+       /* Map 'flags' to the OS-specific settings. */
+       desired_access |= GENERIC_READ;
+       flags_and_attributes = FILE_ATTRIBUTE_NORMAL;
+       if (flags & SERIAL_RDWR)
+               desired_access |= GENERIC_WRITE;
+       if (flags & SERIAL_NONBLOCK)
+               flags_and_attributes |= FILE_FLAG_OVERLAPPED;
+
+       hdl = CreateFile(serial->port, desired_access, 0, 0,
+                        OPEN_EXISTING, flags_and_attributes, 0);
        if (hdl == INVALID_HANDLE_VALUE) {
                sr_err("Error opening serial port '%s'.", serial->port);
                return SR_ERR;
        }
 #else
-       if ((serial->fd = open(serial->port, flags)) < 0) {
+       /* Map 'flags' to the OS-specific settings. */
+       if (flags & SERIAL_RDWR)
+               flags_local |= O_RDWR;
+       if (flags & SERIAL_RDONLY)
+               flags_local |= O_RDONLY;
+       if (flags & SERIAL_NONBLOCK)
+               flags_local |= O_NONBLOCK;
+
+       if ((serial->fd = open(serial->port, flags_local)) < 0) {
                sr_err("Error opening serial port '%s': %s.", serial->port,
                       strerror(errno));
                return SR_ERR;
-       } else
-               sr_spew("Opened serial port '%s' (fd %d).", serial->port, serial->fd);
+       }
+
+       sr_spew("Opened serial port '%s' (fd %d).", serial->port, serial->fd);
 #endif
 
        if (serial->serialcomm)