X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;ds=sidebyside;f=src%2Fscpi%2Fscpi.c;h=8d24ceea97e29c88de244fae03600a8cf52b6507;hb=HEAD;hp=ec0ddc555c73b37b6cdec6799ecf9573fee3534c;hpb=191af3d9ca2f347810a12a3f9d87bdc8c8db15aa;p=libsigrok.git

diff --git a/src/scpi/scpi.c b/src/scpi/scpi.c
index ec0ddc55..8d24ceea 100644
--- a/src/scpi/scpi.c
+++ b/src/scpi/scpi.c
@@ -38,6 +38,7 @@ static const char *scpi_vendors[][2] = {
 	{ "Keysight Technologies", "Keysight" },
 	{ "PHILIPS", "Philips" },
 	{ "RIGOL TECHNOLOGIES", "Rigol" },
+	{ "Siglent Technologies", "Siglent" },
 };
 
 /**
@@ -315,33 +316,32 @@ SR_PRIV GSList *sr_scpi_scan(struct drv_context *drvc, GSList *options,
 {
 	GSList *resources, *l, *devices;
 	struct sr_dev_inst *sdi;
-	const char *resource = NULL;
-	const char *serialcomm = NULL;
+	const char *resource, *conn;
+	const char *serialcomm, *comm;
 	gchar **res;
 	unsigned i;
 
-	for (l = options; l; l = l->next) {
-		struct sr_config *src = l->data;
-		switch (src->key) {
-		case SR_CONF_CONN:
-			resource = g_variant_get_string(src->data, NULL);
-			break;
-		case SR_CONF_SERIALCOMM:
-			serialcomm = g_variant_get_string(src->data, NULL);
-			break;
-		}
-	}
+	resource = NULL;
+	serialcomm = NULL;
+	(void)sr_serial_extract_options(options, &resource, &serialcomm);
 
 	devices = NULL;
 	for (i = 0; i < ARRAY_SIZE(scpi_devs); i++) {
-		if ((resource && strcmp(resource, scpi_devs[i]->prefix))
-		    || !scpi_devs[i]->scan)
+		if (resource && strcmp(resource, scpi_devs[i]->prefix) != 0)
+			continue;
+		if (!scpi_devs[i]->scan)
 			continue;
 		resources = scpi_devs[i]->scan(drvc);
 		for (l = resources; l; l = l->next) {
 			res = g_strsplit(l->data, ":", 2);
-			if (res[0] && (sdi = sr_scpi_scan_resource(drvc, res[0],
-			               serialcomm ? serialcomm : res[1], probe_device))) {
+			if (!res[0]) {
+				g_strfreev(res);
+				continue;
+			}
+			conn = res[0];
+			comm = serialcomm ? : res[1];
+			sdi = sr_scpi_scan_resource(drvc, conn, comm, probe_device);
+			if (sdi) {
 				devices = g_slist_append(devices, sdi);
 				sdi->connection_id = g_strdup(l->data);
 			}
@@ -1038,7 +1038,29 @@ SR_PRIV int sr_scpi_get_block(struct sr_scpi_dev_inst *scpi,
 	buf[0] = response->str[1];
 	buf[1] = '\0';
 	ret = sr_atol(buf, &llen);
-	if ((ret != SR_OK) || (llen == 0)) {
+	/*
+	 * The form "#0..." is legal, and does not mean "empty response",
+	 * but means that the number of data bytes is not known (or was
+	 * not communicated) at this time. Instead the block ends at an
+	 * "END MESSAGE" termination sequence. Which translates to active
+	 * EOI while a text line termination is sent (CR or LF, and this
+	 * text line termination is not part of the block's data value).
+	 * Since this kind of #0... response is considered rare, and
+	 * depends on specific support in physical transports underneath
+	 * the SCPI layer, let's flag the condition and bail out with an
+	 * error here, until it's found to be a genuine issue in the field.
+	 *
+	 * The SCPI 1999.0 specification (see page 220 and following in
+	 * the "HCOPy" description) references IEEE 488.2, especially
+	 * section 8.7.9 for DEFINITE LENGTH and section 8.7.10 for
+	 * INDEFINITE LENGTH ARBITRARY BLOCK RESPONSE DATA. The latter
+	 * with a leading "#0" length and a trailing "NL^END" marker.
+	 */
+	if (ret == SR_OK && !llen) {
+		sr_err("unsupported INDEFINITE LENGTH ARBITRARY BLOCK RESPONSE");
+		ret = SR_ERR_NA;
+	}
+	if (ret != SR_OK) {
 		g_mutex_unlock(&scpi->scpi_mutex);
 		g_string_free(response, TRUE);
 		return ret;