X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=src%2Fscpi%2Fscpi.c;h=2477cf2323971c314880c3bc235732fd076c0af3;hb=bb0665868eee7ebd569a6563d30c4099cf0c37bb;hp=62e81bebeedab94822786daa317a6d7151b8bdcf;hpb=21bc4353f0bbb80e9548a6ee5fa4e120a115688f;p=libsigrok.git

diff --git a/src/scpi/scpi.c b/src/scpi/scpi.c
index 62e81beb..2477cf23 100644
--- a/src/scpi/scpi.c
+++ b/src/scpi/scpi.c
@@ -100,7 +100,7 @@ static const struct sr_scpi_dev_inst *scpi_devs[] = {
 #ifdef HAVE_LIBGPIB
 	&scpi_libgpib_dev,
 #endif
-#ifdef HAVE_LIBSERIALPORT
+#ifdef HAVE_SERIAL_COMM
 	&scpi_serial_dev, /* Must be last as it matches any resource. */
 #endif
 };
@@ -407,6 +407,21 @@ SR_PRIV int sr_scpi_open(struct sr_scpi_dev_inst *scpi)
 	return scpi->open(scpi);
 }
 
+/**
+ * Get the connection ID of the SCPI device.
+ *
+ * @param scpi Previously initialized SCPI device structure.
+ * @param connection_id Pointer where to store the connection ID. The caller
+ *        is responsible for g_free()ing the string when it is no longer needed.
+ *
+ * @return SR_OK on success, SR_ERR on failure.
+ */
+SR_PRIV int sr_scpi_connection_id(struct sr_scpi_dev_inst *scpi,
+		char **connection_id)
+{
+	return scpi->connection_id(scpi, connection_id);
+}
+
 /**
  * Add an event source for an SCPI device.
  *
@@ -946,6 +961,7 @@ SR_PRIV int sr_scpi_get_block(struct sr_scpi_dev_inst *scpi,
 {
 	int ret;
 	GString* response;
+	gsize oldlen;
 	char buf[10];
 	long llen;
 	long datalen;
@@ -975,14 +991,14 @@ SR_PRIV int sr_scpi_get_block(struct sr_scpi_dev_inst *scpi,
 	*scpi_response = NULL;
 
 	/* Get (the first chunk of) the response. */
-	while (response->len < 2) {
+	do {
 		ret = scpi_read_response(scpi, response, timeout);
 		if (ret < 0) {
 			g_mutex_unlock(&scpi->scpi_mutex);
 			g_string_free(response, TRUE);
 			return ret;
 		}
-	}
+	} while (response->len < 2);
 
 	/*
 	 * SCPI protocol data blocks are preceeded with a length spec.
@@ -1029,25 +1045,33 @@ SR_PRIV int sr_scpi_get_block(struct sr_scpi_dev_inst *scpi,
 	g_string_erase(response, 0, 2 + llen);
 
 	/*
-	 * If the initially assumed length does not cover the data block
-	 * length, then re-allocate the buffer size to the now known
-	 * length, and keep reading more chunks of response data.
+	 * Re-allocate the buffer size to the now known length
+	 * and keep reading more chunks of response data.
 	 */
-	if (response->len < (unsigned long)(datalen)) {
-		int oldlen = response->len;
-		g_string_set_size(response, datalen);
-		g_string_set_size(response, oldlen);
-	}
-
-	while (response->len < (unsigned long)(datalen)) {
-		ret = scpi_read_response(scpi, response, timeout);
-		if (ret < 0) {
-			g_mutex_unlock(&scpi->scpi_mutex);
-			g_string_free(response, TRUE);
-			return ret;
-		}
-		if (ret > 0)
-			timeout = g_get_monotonic_time() + scpi->read_timeout_us;
+	oldlen = response->len;
+	g_string_set_size(response, datalen);
+	g_string_set_size(response, oldlen);
+
+	if (oldlen < (unsigned long)(datalen)) {
+		do {
+			oldlen = response->len;
+			ret = scpi_read_response(scpi, response, timeout);
+
+			/* On timeout truncate the buffer and send the partial response
+			 * instead of getting stuck on timeouts...
+			 */
+			if (ret == SR_ERR_TIMEOUT) {
+				datalen = oldlen;
+				break;
+			}
+			if (ret < 0) {
+				g_mutex_unlock(&scpi->scpi_mutex);
+				g_string_free(response, TRUE);
+				return ret;
+			}
+			if (ret > 0)
+				timeout = g_get_monotonic_time() + scpi->read_timeout_us;
+		} while (response->len < (unsigned long)(datalen));
 	}
 
 	g_mutex_unlock(&scpi->scpi_mutex);