X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=src%2Fscpi%2Fscpi.c;h=48e6a48495c9bfaba591147a12f715b67fe0b493;hb=b6be55ce95b8d4d00d64874a05c022846e43cec4;hp=38d74ab5ffcc17989d478e9a9cb93fcf3c9877a0;hpb=558d438d1f944284be13bec06db7ca67876ea234;p=libsigrok.git
diff --git a/src/scpi/scpi.c b/src/scpi/scpi.c
index 38d74ab5..48e6a484 100644
--- a/src/scpi/scpi.c
+++ b/src/scpi/scpi.c
@@ -17,6 +17,7 @@
* along with this program. If not, see .
*/
+#include
#include
#include
#include
@@ -89,7 +90,7 @@ static const struct sr_scpi_dev_inst *scpi_devs[] = {
&scpi_libgpib_dev,
#endif
#ifdef HAVE_LIBSERIALPORT
- &scpi_serial_dev, /* must be last as it matches any resource */
+ &scpi_serial_dev, /* Must be last as it matches any resource. */
#endif
};
@@ -109,12 +110,16 @@ static struct sr_dev_inst *sr_scpi_scan_resource(struct drv_context *drvc,
return NULL;
};
- if ((sdi = probe_device(scpi)))
- return sdi;
+ sdi = probe_device(scpi);
sr_scpi_close(scpi);
- sr_scpi_free(scpi);
- return NULL;
+
+ if (sdi)
+ sdi->status = SR_ST_INACTIVE;
+ else
+ sr_scpi_free(scpi);
+
+ return sdi;
}
SR_PRIV GSList *sr_scpi_scan(struct drv_context *drvc, GSList *options,
@@ -185,7 +190,7 @@ SR_PRIV struct sr_scpi_dev_inst *scpi_dev_inst_new(struct drv_context *drvc,
scpi = g_malloc(sizeof(*scpi));
*scpi = *scpi_dev;
scpi->priv = g_malloc0(scpi->priv_size);
- scpi->read_timeout_ms = 1000;
+ scpi->read_timeout_us = 1000 * 1000;
params = g_strsplit(resource, "/", 0);
if (scpi->dev_inst_new(scpi->priv, drvc, resource,
params, serialcomm) != SR_OK) {
@@ -209,7 +214,7 @@ SR_PRIV struct sr_scpi_dev_inst *scpi_dev_inst_new(struct drv_context *drvc,
*/
SR_PRIV int sr_scpi_open(struct sr_scpi_dev_inst *scpi)
{
- return scpi->open(scpi->priv);
+ return scpi->open(scpi);
}
/**
@@ -291,8 +296,10 @@ SR_PRIV int sr_scpi_send_variadic(struct sr_scpi_dev_inst *scpi,
va_end(args_copy);
/* Allocate buffer and write out command. */
- buf = g_malloc(len + 1);
+ buf = g_malloc0(len + 2);
vsprintf(buf, format, args);
+ if (buf[len - 1] != '\n')
+ buf[len] = '\n';
/* Send command. */
ret = scpi->send(scpi->priv, buf);
@@ -330,6 +337,21 @@ SR_PRIV int sr_scpi_read_data(struct sr_scpi_dev_inst *scpi,
return scpi->read_data(scpi->priv, buf, maxlen);
}
+/**
+ * Send data to SCPI device.
+ *
+ * @param scpi Previously initialised SCPI device structure.
+ * @param buf Buffer with data to send.
+ * @param len Number of bytes to send.
+ *
+ * @return Number of bytes read, or SR_ERR upon failure.
+ */
+SR_PRIV int sr_scpi_write_data(struct sr_scpi_dev_inst *scpi,
+ char *buf, int maxlen)
+{
+ return scpi->write_data(scpi->priv, buf, maxlen);
+}
+
/**
* Check whether a complete SCPI response has been received.
*
@@ -351,18 +373,20 @@ SR_PRIV int sr_scpi_read_complete(struct sr_scpi_dev_inst *scpi)
*/
SR_PRIV int sr_scpi_close(struct sr_scpi_dev_inst *scpi)
{
- return scpi->close(scpi->priv);
+ return scpi->close(scpi);
}
/**
* Free SCPI device.
*
- * @param scpi Previously initialized SCPI device structure.
- *
- * @return SR_OK on success, SR_ERR on failure.
+ * @param scpi Previously initialized SCPI device structure. If NULL,
+ * this function does nothing.
*/
SR_PRIV void sr_scpi_free(struct sr_scpi_dev_inst *scpi)
{
+ if (!scpi)
+ return;
+
scpi->free(scpi->priv);
g_free(scpi->priv);
g_free(scpi);
@@ -380,41 +404,13 @@ SR_PRIV void sr_scpi_free(struct sr_scpi_dev_inst *scpi)
SR_PRIV int sr_scpi_get_string(struct sr_scpi_dev_inst *scpi,
const char *command, char **scpi_response)
{
- char buf[256];
- int len;
GString *response;
- gint64 laststart;
- unsigned int elapsed_ms;
-
- if (command)
- if (sr_scpi_send(scpi, command) != SR_OK)
- return SR_ERR;
-
- if (sr_scpi_read_begin(scpi) != SR_OK)
- return SR_ERR;
-
- laststart = g_get_monotonic_time();
+ response = g_string_sized_new(1024);
- response = g_string_new("");
-
- *scpi_response = NULL;
-
- while (!sr_scpi_read_complete(scpi)) {
- len = sr_scpi_read_data(scpi, buf, sizeof(buf));
- if (len < 0) {
- sr_err("Incompletely read SCPI response.");
+ if (sr_scpi_get_data(scpi, command, &response) != SR_OK) {
+ if (response)
g_string_free(response, TRUE);
- return SR_ERR;
- } else if (len > 0) {
- laststart = g_get_monotonic_time();
- }
- g_string_append_len(response, buf, len);
- elapsed_ms = (g_get_monotonic_time() - laststart) / 1000;
- if (elapsed_ms >= scpi->read_timeout_ms) {
- sr_err("Timed out waiting for SCPI response.");
- g_string_free(response, TRUE);
- return SR_ERR;
- }
+ return SR_ERR;
}
/* Get rid of trailing linefeed if present */
@@ -425,10 +421,90 @@ SR_PRIV int sr_scpi_get_string(struct sr_scpi_dev_inst *scpi,
if (response->len >= 1 && response->str[response->len - 1] == '\r')
g_string_truncate(response, response->len - 1);
- *scpi_response = response->str;
- g_string_free(response, FALSE);
+ sr_spew("Got response: '%.70s', length %" G_GSIZE_FORMAT ".",
+ response->str, response->len);
+
+ *scpi_response = g_string_free(response, FALSE);
+
+ return SR_OK;
+}
+
+/**
+ * Do a non-blocking read of up to the allocated length, and
+ * check if a timeout has occured.
+ *
+ * @param scpi Previously initialised SCPI device structure.
+ * @param response Buffer to which the response is appended.
+ * @param abs_timeout_us Absolute timeout in microseconds
+ *
+ * @return read length on success, SR_ERR* on failure.
+ */
+SR_PRIV int sr_scpi_read_response(struct sr_scpi_dev_inst *scpi,
+ GString *response, gint64 abs_timeout_us)
+{
+ int len, space;
+
+ space = response->allocated_len - response->len;
+ len = sr_scpi_read_data(scpi, &response->str[response->len], space);
+
+ if (len < 0) {
+ sr_err("Incompletely read SCPI response.");
+ return SR_ERR;
+ }
+
+ if (len > 0) {
+ g_string_set_size(response, response->len + len);
+ return len;
+ }
+
+ if (g_get_monotonic_time() > abs_timeout_us) {
+ sr_err("Timed out waiting for SCPI response.");
+ return SR_ERR_TIMEOUT;
+ }
+
+ return 0;
+}
+
+SR_PRIV int sr_scpi_get_data(struct sr_scpi_dev_inst *scpi,
+ const char *command, GString **scpi_response)
+{
+ int ret;
+ GString *response;
+ int space;
+ gint64 timeout;
+
+ /* Optionally send caller provided command. */
+ if (command) {
+ if (sr_scpi_send(scpi, command) != SR_OK)
+ return SR_ERR;
+ }
+
+ /* Initiate SCPI read operation. */
+ if (sr_scpi_read_begin(scpi) != SR_OK)
+ return SR_ERR;
+
+ /* Keep reading until completion or until timeout. */
+ timeout = g_get_monotonic_time() + scpi->read_timeout_us;
+
+ response = *scpi_response;
- sr_spew("Got response: '%.70s', length %d.", *scpi_response, strlen(*scpi_response));
+ while (!sr_scpi_read_complete(scpi)) {
+ /* Resize the buffer when free space drops below a threshold. */
+ space = response->allocated_len - response->len;
+ if (space < 128) {
+ int oldlen = response->len;
+ g_string_set_size(response, oldlen + 1024);
+ g_string_set_size(response, oldlen);
+ }
+
+ /* Read another chunk of the response. */
+ ret = sr_scpi_read_response(scpi, response, timeout);
+
+ if (ret < 0)
+ return ret;
+ if (ret > 0)
+ timeout = g_get_monotonic_time() + scpi->read_timeout_us;
+ }
return SR_OK;
}
@@ -574,7 +650,7 @@ SR_PRIV int sr_scpi_get_opc(struct sr_scpi_dev_inst *scpi)
unsigned int i;
gboolean opc;
- for (i = 0; i < SCPI_READ_RETRIES; ++i) {
+ for (i = 0; i < SCPI_READ_RETRIES; i++) {
sr_scpi_get_bool(scpi, SCPI_CMD_OPC, &opc);
if (opc)
return SR_OK;
@@ -606,7 +682,6 @@ SR_PRIV int sr_scpi_get_floatv(struct sr_scpi_dev_inst *scpi,
gchar **ptr, **tokens;
GArray *response_array;
- ret = SR_OK;
response = NULL;
tokens = NULL;
@@ -663,7 +738,6 @@ SR_PRIV int sr_scpi_get_uint8v(struct sr_scpi_dev_inst *scpi,
gchar **ptr, **tokens;
GArray *response_array;
- ret = SR_OK;
response = NULL;
tokens = NULL;
@@ -699,6 +773,123 @@ SR_PRIV int sr_scpi_get_uint8v(struct sr_scpi_dev_inst *scpi,
return ret;
}
+/**
+ * Send a SCPI command, read the reply, parse it as binary data with a
+ * "definite length block" header and store the as an result in scpi_response.
+ *
+ * @param scpi Previously initialised SCPI device structure.
+ * @param command The SCPI command to send to the device (can be NULL).
+ * @param scpi_response Pointer where to store the parsed result.
+ *
+ * @return SR_OK upon successfully parsing all values, SR_ERR* upon a parsing
+ * error or upon no response. The allocated response must be freed by
+ * the caller in the case of an SR_OK as well as in the case of
+ * parsing error.
+ */
+SR_PRIV int sr_scpi_get_block(struct sr_scpi_dev_inst *scpi,
+ const char *command, GByteArray **scpi_response)
+{
+ int ret;
+ GString* response;
+ char buf[10];
+ long llen;
+ long datalen;
+ gint64 timeout;
+
+ if (command)
+ if (sr_scpi_send(scpi, command) != SR_OK)
+ return SR_ERR;
+
+ if (sr_scpi_read_begin(scpi) != SR_OK)
+ return SR_ERR;
+
+ /*
+ * Assume an initial maximum length, optionally gets adjusted below.
+ * Prepare a NULL return value for when error paths will be taken.
+ */
+ response = g_string_sized_new(1024);
+
+ timeout = g_get_monotonic_time() + scpi->read_timeout_us;
+
+ *scpi_response = NULL;
+
+ /* Get (the first chunk of) the response. */
+ while (response->len < 2) {
+ ret = sr_scpi_read_response(scpi, response, timeout);
+ if (ret < 0) {
+ g_string_free(response, TRUE);
+ return ret;
+ }
+ }
+
+ /*
+ * SCPI protocol data blocks are preceeded with a length spec.
+ * The length spec consists of a '#' marker, one digit which
+ * specifies the character count of the length spec, and the
+ * respective number of characters which specify the data block's
+ * length. Raw data bytes follow (thus one must no longer assume
+ * that the received input stream would be an ASCIIZ string).
+ *
+ * Get the data block length, and strip off the length spec from
+ * the input buffer, leaving just the data bytes.
+ */
+ if (response->str[0] != '#') {
+ g_string_free(response, TRUE);
+ return SR_ERR_DATA;
+ }
+ buf[0] = response->str[1];
+ buf[1] = '\0';
+ ret = sr_atol(buf, &llen);
+ if ((ret != SR_OK) || (llen == 0)) {
+ g_string_free(response, TRUE);
+ return ret;
+ }
+
+ while (response->len < (unsigned long)(2 + llen)) {
+ ret = sr_scpi_read_response(scpi, response, timeout);
+ if (ret < 0) {
+ g_string_free(response, TRUE);
+ return ret;
+ }
+ }
+
+ memcpy(buf, &response->str[2], llen);
+ buf[llen] = '\0';
+ ret = sr_atol(buf, &datalen);
+ if ((ret != SR_OK) || (datalen == 0)) {
+ g_string_free(response, TRUE);
+ return ret;
+ }
+ 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.
+ */
+ 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 = sr_scpi_read_response(scpi, response, timeout);
+ if (ret < 0) {
+ g_string_free(response, TRUE);
+ return ret;
+ }
+ if (ret > 0)
+ timeout = g_get_monotonic_time() + scpi->read_timeout_us;
+ }
+
+ /* Convert received data to byte array. */
+ *scpi_response = g_byte_array_new_take(
+ (guint8*)g_string_free(response, FALSE), datalen);
+
+ return SR_OK;
+}
+
/**
* Send the *IDN? SCPI command, receive the reply, parse it and store the
* reply as a sr_scpi_hw_info structure in the supplied scpi_response pointer.
@@ -760,17 +951,17 @@ SR_PRIV int sr_scpi_get_hw_id(struct sr_scpi_dev_inst *scpi,
/**
* Free a sr_scpi_hw_info struct.
*
- * @param hw_info Pointer to the struct to free.
- *
- * This function is safe to call with a NULL pointer.
+ * @param hw_info Pointer to the struct to free. If NULL, this
+ * function does nothing.
*/
SR_PRIV void sr_scpi_hw_info_free(struct sr_scpi_hw_info *hw_info)
{
- if (hw_info) {
- g_free(hw_info->manufacturer);
- g_free(hw_info->model);
- g_free(hw_info->serial_number);
- g_free(hw_info->firmware_version);
- g_free(hw_info);
- }
+ if (!hw_info)
+ return;
+
+ g_free(hw_info->manufacturer);
+ g_free(hw_info->model);
+ g_free(hw_info->serial_number);
+ g_free(hw_info->firmware_version);
+ g_free(hw_info);
}