From: Martin Ling <redacted>
Date: Tue, 3 Dec 2013 22:56:32 +0000 (+0000)
Subject: Add sr_scpi_read() operation for reading arbitrary data.
X-Git-Tag: libsigrok-0.3.0~496
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=a1ff9c1897262faa3b284ea5bb82593c45de70d0;p=libsigrok.git

Add sr_scpi_read() operation for reading arbitrary data.
---

diff --git a/hardware/common/scpi.c b/hardware/common/scpi.c
index f8810a59..0091ba34 100644
--- a/hardware/common/scpi.c
+++ b/hardware/common/scpi.c
@@ -146,6 +146,21 @@ SR_PRIV int sr_scpi_receive(struct sr_scpi_dev_inst *scpi,
 	return scpi->receive(scpi->priv, scpi_response);
 }
 
+/**
+ * Read part of a response from SCPI device.
+ *
+ * @param scpi Previously initialised SCPI device structure.
+ * @param buf Buffer to store result.
+ * @param maxlen Maximum number of bytes to read.
+ *
+ * @return Number of bytes read, or SR_ERR upon failure.
+ */
+SR_PRIV int sr_scpi_read(struct sr_scpi_dev_inst *scpi,
+			char *buf, int maxlen)
+{
+	return scpi->read(scpi->priv, buf, maxlen);
+}
+
 /**
  * Close SCPI device.
  *
diff --git a/hardware/common/scpi_serial.c b/hardware/common/scpi_serial.c
index cbe51b05..3e149252 100644
--- a/hardware/common/scpi_serial.c
+++ b/hardware/common/scpi_serial.c
@@ -151,6 +151,7 @@ SR_PRIV struct sr_scpi_dev_inst *scpi_serial_dev_inst_new(const char *port,
 	scpi->source_remove = scpi_serial_source_remove;
 	scpi->send = scpi_serial_send;
 	scpi->receive = scpi_serial_receive;
+	scpi->read = serial_read;
 	scpi->close = serial_close;
 	scpi->free = sr_serial_dev_inst_free;
 	scpi->priv = serial;
diff --git a/hardware/common/scpi_usbtmc.c b/hardware/common/scpi_usbtmc.c
index e4c10be6..f7f0958e 100644
--- a/hardware/common/scpi_usbtmc.c
+++ b/hardware/common/scpi_usbtmc.c
@@ -111,6 +111,21 @@ SR_PRIV int scpi_usbtmc_receive(void *priv, char **scpi_response)
 	return SR_OK;
 }
 
+SR_PRIV int scpi_usbtmc_read(void *priv, unsigned char *buf, int maxlen)
+{
+	struct sr_usbtmc_dev_inst *usbtmc = priv;
+	int len;
+
+	len = read(usbtmc->fd, buf, maxlen);
+
+	if (len < 0) {
+		sr_err("Read error: %s", strerror(errno));
+		return SR_ERR;
+	}
+
+	return len;
+}
+
 SR_PRIV int scpi_usbtmc_close(void *priv)
 {
 	struct sr_usbtmc_dev_inst *usbtmc = priv;
@@ -139,6 +154,7 @@ SR_PRIV struct sr_scpi_dev_inst *scpi_usbtmc_dev_inst_new(const char *device)
 	scpi->source_remove = scpi_usbtmc_source_remove;
 	scpi->send = scpi_usbtmc_send;
 	scpi->receive = scpi_usbtmc_receive;
+	scpi->read = scpi_usbtmc_read;
 	scpi->close = scpi_usbtmc_close;
 	scpi->free = sr_usbtmc_dev_inst_free;
 	scpi->priv = usbtmc;
diff --git a/libsigrok-internal.h b/libsigrok-internal.h
index 0457c509..59359f0c 100644
--- a/libsigrok-internal.h
+++ b/libsigrok-internal.h
@@ -292,6 +292,7 @@ struct sr_scpi_dev_inst {
 	int (*source_remove)(void *priv);
 	int (*send)(void *priv, const char *command);
 	int (*receive)(void *priv, char **scpi_response);
+	int (*read)(void *priv, char *buf, int maxlen);
 	int (*close)(void *priv);
 	void (*free)(void *priv);
 	void *priv;
@@ -305,6 +306,7 @@ SR_PRIV int sr_scpi_send(struct sr_scpi_dev_inst *scpi,
 			const char *command);
 SR_PRIV int sr_scpi_receive(struct sr_scpi_dev_inst *scpi,
 			char **scpi_response);
+SR_PRIV int sr_scpi_read(struct sr_scpi_dev_inst *scpi, char *buf, int maxlen);
 SR_PRIV int sr_scpi_close(struct sr_scpi_dev_inst *scpi);
 SR_PRIV void sr_scpi_free(struct sr_scpi_dev_inst *scpi);