libsigrok: closedev() now has a return code.

This is useful to allow frontends to react upon close failures in a
way they see fit (e.g. a popup in the GUI, or error message in the CLI).
They can also still ignore the error if they want, of course.

device.c

@@ -61,12 +61,18 @@ int sr_device_plugin_init(struct sr_device_plugin *plugin)
 
 void sr_device_close_all(void)
 {
+	int ret;
 	struct sr_device *device;
 
 	while (devices) {
 		device = devices->data;
-		if (device->plugin && device->plugin->closedev)
+		if (device->plugin && device->plugin->closedev) {
-			device->plugin->closedev(device->plugin_index);
+			ret = device->plugin->closedev(device->plugin_index);
+			if (ret != SR_OK) {
+				sr_err("dev: %s: could not close device %d",
+				       __func__, device->plugin_index);
+			}
+		}
 		sr_device_destroy(device);
 	}
 }

hardware/alsa/alsa.c

@@ -108,21 +108,28 @@ static int hw_opendev(int device_index)
 	return SR_OK;
 }
 
-static void hw_closedev(int device_index)
+static int hw_closedev(int device_index)
 {
 	struct sr_device_instance *sdi;
 	struct alsa *alsa;
 
-	if (!(sdi = sr_get_device_instance(device_instances, device_index)))
+	if (!(sdi = sr_get_device_instance(device_instances, device_index))) {
-		return;
+		sr_err("alsa: %s: sdi was NULL", __func__);
-	alsa = sdi->priv;
+		return SR_ERR; /* TODO: SR_ERR_ARG? */
-	if (!alsa)
+	}
-		return;
 
+	if (!(alsa = sdi->priv)) {
+		sr_err("alsa: %s: sdi->priv was NULL", __func__);
+		return SR_ERR; /* TODO: SR_ERR_ARG? */
+	}
+
+	// TODO: Return values of snd_*?
 	if (alsa->hw_params)
 		snd_pcm_hw_params_free(alsa->hw_params);
 	if (alsa->capture_handle)
 		snd_pcm_close(alsa->capture_handle);
+
+	return SR_OK;
 }
 
 static void hw_cleanup(void)

hardware/asix-sigma/asix-sigma.c

@@ -675,19 +675,28 @@ static int configure_probes(struct sr_device_instance *sdi, GSList *probes)
 	return SR_OK;
 }
 
-static void hw_closedev(int device_index)
+static int hw_closedev(int device_index)
 {
 	struct sr_device_instance *sdi;
 	struct sigma *sigma;
 
-	if ((sdi = sr_get_device_instance(device_instances, device_index)))
+	if (!(sdi = sr_get_device_instance(device_instances, device_index))) {
-	{
+		sr_err("asix: %s: sdi was NULL", __func__);
-		sigma = sdi->priv;
+		return SR_ERR; /* TODO: SR_ERR_ARG? */
-		if (sdi->status == SR_ST_ACTIVE)
-			ftdi_usb_close(&sigma->ftdic);
-
-		sdi->status = SR_ST_INACTIVE;
 	}
+
+	if (!(sigma = sdi->priv)) {
+		sr_err("asix: %s: sdi->priv was NULL", __func__);
+		return SR_ERR; /* TODO: SR_ERR_ARG? */
+	}
+
+	/* TODO */
+	if (sdi->status == SR_ST_ACTIVE)
+		ftdi_usb_close(&sigma->ftdic);
+
+	sdi->status = SR_ST_INACTIVE;
+
+	return SR_OK;
 }
 
 static void hw_cleanup(void)

hardware/chronovu-la8/chronovu-la8.c

@@ -632,25 +632,26 @@ static int set_samplerate(struct sr_device_instance *sdi, uint64_t samplerate)
 	return SR_OK;
 }
 
-static void hw_closedev(int device_index)
+static int hw_closedev(int device_index)
 {
 	struct sr_device_instance *sdi;
 	struct la8 *la8;
 
 	if (!(sdi = sr_get_device_instance(device_instances, device_index))) {
 		sr_err("la8: %s: sdi was NULL", __func__);
-		return;
+		return SR_ERR; /* TODO: SR_ERR_ARG? */
 	}
 
 	if (!(la8 = sdi->priv)) {
 		sr_err("la8: %s: sdi->priv was NULL", __func__);
-		return;
+		return SR_ERR; /* TODO: SR_ERR_ARG? */
 	}
 
 	sr_dbg("la8: closing device");
 
 	if (sdi->status == SR_ST_ACTIVE) {
 		sr_dbg("la8: %s: status ACTIVE, closing device", __func__);
+		/* TODO: Really ignore errors here, or return SR_ERR? */
 		(void) la8_close_usb_reset_sequencer(la8); /* Ignore errors. */
 	} else {
 		sr_dbg("la8: %s: status not ACTIVE, nothing to do", __func__);
@@ -660,6 +661,8 @@ static void hw_closedev(int device_index)
 
 	sr_dbg("la8: %s: freeing sample buffers", __func__);
 	free(la8->final_buf);
+
+	return SR_OK;
 }
 
 static void hw_cleanup(void)

hardware/demo/demo.c

@@ -121,15 +121,18 @@ static int hw_opendev(int device_index)
 	device_index = device_index;
 
 	/* Nothing needed so far. */
+
 	return SR_OK;
 }
 
-static void hw_closedev(int device_index)
+static int hw_closedev(int device_index)
 {
 	/* Avoid compiler warnings. */
 	device_index = device_index;
 
 	/* Nothing needed so far. */
+
+	return SR_OK;
 }
 
 static void hw_cleanup(void)

hardware/link-mso19/link-mso19.c

@@ -539,18 +539,23 @@ static int hw_opendev(int device_index)
 	return SR_OK;
 }
 
-static void hw_closedev(int device_index)
+static int hw_closedev(int device_index)
 {
 	struct sr_device_instance *sdi;
 
-	if (!(sdi = sr_get_device_instance(device_instances, device_index)))
+	if (!(sdi = sr_get_device_instance(device_instances, device_index))) {
-		return;
+		sr_err("mso19: %s: sdi was NULL", __func__);
+		return SR_ERR; /* TODO: SR_ERR_ARG? */
+	}
 
+	/* TODO */
 	if (sdi->serial->fd != -1) {
 		serial_close(sdi->serial->fd);
 		sdi->serial->fd = -1;
 		sdi->status = SR_ST_INACTIVE;
 	}
+
+	return SR_OK;
 }
 
 static void *hw_get_device_info(int device_index, int device_info_id)

hardware/openbench-logic-sniffer/ols.c

@@ -458,18 +458,23 @@ static int hw_opendev(int device_index)
 	return SR_OK;
 }
 
-static void hw_closedev(int device_index)
+static int hw_closedev(int device_index)
 {
 	struct sr_device_instance *sdi;
 
-	if (!(sdi = sr_get_device_instance(device_instances, device_index)))
+	if (!(sdi = sr_get_device_instance(device_instances, device_index))) {
-		return;
+		sr_err("ols: %s: sdi was NULL", __func__);
+		return SR_ERR; /* TODO: SR_ERR_ARG? */
+	}
 
+	/* TODO */
 	if (sdi->serial->fd != -1) {
 		serial_close(sdi->serial->fd);
 		sdi->serial->fd = -1;
 		sdi->status = SR_ST_INACTIVE;
 	}
+
+	return SR_OK;
 }
 
 static void hw_cleanup(void)

hardware/saleae-logic/saleae-logic.c

@@ -394,12 +394,19 @@ static int hw_opendev(int device_index)
 	return SR_OK;
 }
 
-static void hw_closedev(int device_index)
+static int hw_closedev(int device_index)
 {
 	struct sr_device_instance *sdi;
 
-	if ((sdi = sr_get_device_instance(device_instances, device_index)))
+	if (!(sdi = sr_get_device_instance(device_instances, device_index))) {
-		close_device(sdi);
+		sr_err("logic: %s: sdi was NULL", __func__);
+		return SR_ERR; /* TODO: SR_ERR_ARG? */
+	}
+
+	/* TODO */
+	close_device(sdi);
+
+	return SR_OK;
 }
 
 static void hw_cleanup(void)

hardware/zeroplus-logic-cube/zeroplus.c

@@ -370,12 +370,19 @@ static int hw_opendev(int device_index)
 	return SR_OK;
 }
 
-static void hw_closedev(int device_index)
+static int hw_closedev(int device_index)
 {
 	struct sr_device_instance *sdi;
 
-	if ((sdi = sr_get_device_instance(device_instances, device_index)))
+	if (!(sdi = sr_get_device_instance(device_instances, device_index))) {
-		close_device(sdi);
+		sr_err("lap-c: %s: sdi was NULL", __func__);
+		return SR_ERR; /* TODO: SR_ERR_ARG? */
+	}
+
+	/* TODO */
+	close_device(sdi);
+
+	return SR_OK;
 }
 
 static void hw_cleanup(void)

sigrok.h

@@ -335,7 +335,7 @@ struct sr_device_plugin {
 
 	/* Device-specific */
 	int (*opendev) (int device_index);
-	void (*closedev) (int device_index);
+	int (*closedev) (int device_index);
 	void *(*get_device_info) (int device_index, int device_info_id);
 	int (*get_status) (int device_index);
 	int *(*get_capabilities) (void);