sr_dev_close(): Set status to SR_ST_INACTIVE.

[libsigrok.git] / src / device.c

diff --git a/src/device.c b/src/device.c
index 38ac003cf01d7433b9c1767ccf3ace01d70329db..9ba8bfc570cb43ed9bec54a661904b45ec6f7e88 100644 (file)
--- a/src/device.c
+++ b/src/device.c
@@ -136,7 +136,9 @@ SR_API int sr_dev_channel_enable(struct sr_channel *channel, gboolean state)
 }
 
 /* Returns the next enabled channel, wrapping around if necessary. */
+/** @private */
 SR_PRIV struct sr_channel *sr_next_enabled_channel(const struct sr_dev_inst *sdi,
+
                struct sr_channel *cur_channel)
 {
        struct sr_channel *next_channel;
@@ -409,7 +411,8 @@ SR_PRIV struct sr_usb_dev_inst *sr_usb_dev_inst_new(uint8_t bus,
 /**
  * Free struct sr_usb_dev_inst * allocated by sr_usb_dev_inst().
  *
- * @param usb The struct sr_usb_dev_inst * to free. Must not be NULL.
+ * @param usb The struct sr_usb_dev_inst * to free. If NULL, this
+ *            function does nothing.
  *
  * @private
  */
@@ -457,12 +460,16 @@ SR_PRIV struct sr_serial_dev_inst *sr_serial_dev_inst_new(const char *port,
 /**
  * Free struct sr_serial_dev_inst * allocated by sr_serial_dev_inst().
  *
- * @param serial The struct sr_serial_dev_inst * to free. Must not be NULL.
+ * @param serial The struct sr_serial_dev_inst * to free. If NULL, this
+ *               function will do nothing.
  *
  * @private
  */
 SR_PRIV void sr_serial_dev_inst_free(struct sr_serial_dev_inst *serial)
 {
+       if (!serial)
+               return;
+
        g_free(serial->port);
        g_free(serial->serialcomm);
        g_free(serial);
@@ -484,6 +491,9 @@ SR_PRIV struct sr_usbtmc_dev_inst *sr_usbtmc_dev_inst_new(const char *device)
 /** @private */
 SR_PRIV void sr_usbtmc_dev_inst_free(struct sr_usbtmc_dev_inst *usbtmc)
 {
+       if (!usbtmc)
+               return;
+
        g_free(usbtmc->device);
        g_free(usbtmc);
 }
@@ -535,11 +545,19 @@ SR_API int sr_dev_clear(const struct sr_dev_driver *driver)
 }
 
 /**
- * Open the specified device.
+ * Open the specified device instance.
+ *
+ * If the device instance is already open (sdi->status == SR_ST_ACTIVE),
+ * SR_ERR will be returned and no re-opening of the device will be attempted.
+ *
+ * If opening was successful, sdi->status is set to SR_ST_ACTIVE, otherwise
+ * it will be left unchanged.
  *
  * @param sdi Device instance to use. Must not be NULL.
  *
- * @return SR_OK upon success, a negative error code upon errors.
+ * @retval SR_OK Success.
+ * @retval SR_ERR_ARG Invalid arguments.
+ * @retval SR_ERR Device instance was already active, or other error.
  *
  * @since 0.2.0
  */
@@ -548,19 +566,40 @@ SR_API int sr_dev_open(struct sr_dev_inst *sdi)
        int ret;
 
        if (!sdi || !sdi->driver || !sdi->driver->dev_open)
+               return SR_ERR_ARG;
+
+       if (sdi->status == SR_ST_ACTIVE) {
+               sr_err("%s: Device instance already active, can't re-open.",
+                       sdi->driver->name);
                return SR_ERR;
+       }
+
+       sr_dbg("%s: Opening device instance.", sdi->driver->name);
 
        ret = sdi->driver->dev_open(sdi);
 
+       if (ret == SR_OK)
+               sdi->status = SR_ST_ACTIVE;
+
        return ret;
 }
 
 /**
- * Close the specified device.
+ * Close the specified device instance.
+ *
+ * If the device instance is not open (sdi->status != SR_ST_ACTIVE),
+ * SR_ERR_DEV_CLOSED will be returned and no closing will be attempted.
+ *
+ * Note: sdi->status will be set to SR_ST_INACTIVE, regardless of whether
+ * there are any errors during closing of the device instance (any errors
+ * will be reported via error code and log message, though).
  *
  * @param sdi Device instance to use. Must not be NULL.
  *
- * @return SR_OK upon success, a negative error code upon errors.
+ * @retval SR_OK Success.
+ * @retval SR_ERR_ARG Invalid arguments.
+ * @retval SR_ERR_DEV_CLOSED Device instance was not active.
+ * @retval SR_ERR Other error.
  *
  * @since 0.2.0
  */
@@ -569,7 +608,17 @@ SR_API int sr_dev_close(struct sr_dev_inst *sdi)
        int ret;
 
        if (!sdi || !sdi->driver || !sdi->driver->dev_close)
-               return SR_ERR;
+               return SR_ERR_ARG;
+
+       if (sdi->status != SR_ST_ACTIVE) {
+               sr_err("%s: Device instance not active, can't close.",
+                       sdi->driver->name);
+               return SR_ERR_DEV_CLOSED;
+       }
+
+       sdi->status = SR_ST_INACTIVE;
+
+       sr_dbg("%s: Closing device instance.", sdi->driver->name);
 
        ret = sdi->driver->dev_close(sdi);