From: Guido Trentalancia <redacted>
Date: Sun, 18 Nov 2018 14:32:00 +0000 (+0100)
Subject: hameg-hmo: Only update states after successful SCPI SET.
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=1203acc78fce690d6c63f734e1283091192c2d08;p=libsigrok.git

hameg-hmo: Only update states after successful SCPI SET.

Update the oscilloscope state with new settings only after
they have been successfully stored in the device to avoid
an inconsistent state in case of SCPI SET command failure.
---

diff --git a/src/hardware/hameg-hmo/api.c b/src/hardware/hameg-hmo/api.c
index 71d3a986..a7204219 100644
--- a/src/hardware/hameg-hmo/api.c
+++ b/src/hardware/hameg-hmo/api.c
@@ -257,7 +257,7 @@ static int config_set(uint32_t key, GVariant *data,
 	struct dev_context *devc;
 	const struct scope_config *model;
 	struct scope_state *state;
-	double tmp_d;
+	double tmp_d, tmp_d2;
 	gboolean update_sample_rate;
 
 	if (!sdi)
@@ -284,13 +284,13 @@ static int config_set(uint32_t key, GVariant *data,
 	case SR_CONF_TRIGGER_SOURCE:
 		if ((idx = std_str_idx(data, *model->trigger_sources, model->num_trigger_sources)) < 0)
 			return SR_ERR_ARG;
-		state->trigger_source = idx;
 		g_snprintf(command, sizeof(command),
 			   (*model->scpi_dialect)[SCPI_CMD_SET_TRIGGER_SOURCE],
 			   (*model->trigger_sources)[idx]);
 		if (sr_scpi_send(sdi->conn, command) != SR_OK ||
 		    sr_scpi_get_opc(sdi->conn) != SR_OK)
 			return SR_ERR;
+		state->trigger_source = idx;
 		ret = SR_OK;
 		break;
 	case SR_CONF_VDIV:
@@ -300,7 +300,6 @@ static int config_set(uint32_t key, GVariant *data,
 			return SR_ERR_ARG;
 		if ((j = std_cg_idx(cg, devc->analog_groups, model->analog_channels)) < 0)
 			return SR_ERR_ARG;
-		state->analog_channels[j].vdiv = idx;
 		g_ascii_formatd(float_str, sizeof(float_str), "%E",
 			(float) (*model->vdivs)[idx][0] / (*model->vdivs)[idx][1]);
 		g_snprintf(command, sizeof(command),
@@ -309,12 +308,12 @@ static int config_set(uint32_t key, GVariant *data,
 		if (sr_scpi_send(sdi->conn, command) != SR_OK ||
 		    sr_scpi_get_opc(sdi->conn) != SR_OK)
 			return SR_ERR;
+		state->analog_channels[j].vdiv = idx;
 		ret = SR_OK;
 		break;
 	case SR_CONF_TIMEBASE:
 		if ((idx = std_u64_tuple_idx(data, *model->timebases, model->num_timebases)) < 0)
 			return SR_ERR_ARG;
-		state->timebase = idx;
 		g_ascii_formatd(float_str, sizeof(float_str), "%E",
 			(float) (*model->timebases)[idx][0] / (*model->timebases)[idx][1]);
 		g_snprintf(command, sizeof(command),
@@ -323,6 +322,7 @@ static int config_set(uint32_t key, GVariant *data,
 		if (sr_scpi_send(sdi->conn, command) != SR_OK ||
 		    sr_scpi_get_opc(sdi->conn) != SR_OK)
 			return SR_ERR;
+		state->timebase = idx;
 		ret = SR_OK;
 		update_sample_rate = TRUE;
 		break;
@@ -330,30 +330,30 @@ static int config_set(uint32_t key, GVariant *data,
 		tmp_d = g_variant_get_double(data);
 		if (tmp_d < 0.0 || tmp_d > 1.0)
 			return SR_ERR;
-		state->horiz_triggerpos = tmp_d;
-		tmp_d = -(tmp_d - 0.5) *
+		tmp_d2 = -(tmp_d - 0.5) *
 			((double) (*model->timebases)[state->timebase][0] /
 			(*model->timebases)[state->timebase][1])
 			 * model->num_xdivs;
-		g_ascii_formatd(float_str, sizeof(float_str), "%E", tmp_d);
+		g_ascii_formatd(float_str, sizeof(float_str), "%E", tmp_d2);
 		g_snprintf(command, sizeof(command),
 			   (*model->scpi_dialect)[SCPI_CMD_SET_HORIZ_TRIGGERPOS],
 			   float_str);
 		if (sr_scpi_send(sdi->conn, command) != SR_OK ||
 		    sr_scpi_get_opc(sdi->conn) != SR_OK)
 			return SR_ERR;
+		state->horiz_triggerpos = tmp_d;
 		ret = SR_OK;
 		break;
 	case SR_CONF_TRIGGER_SLOPE:
 		if ((idx = std_str_idx(data, *model->trigger_slopes, model->num_trigger_slopes)) < 0)
 			return SR_ERR_ARG;
-		state->trigger_slope = idx;
 		g_snprintf(command, sizeof(command),
 			   (*model->scpi_dialect)[SCPI_CMD_SET_TRIGGER_SLOPE],
 			   (*model->trigger_slopes)[idx]);
 		if (sr_scpi_send(sdi->conn, command) != SR_OK ||
 		    sr_scpi_get_opc(sdi->conn) != SR_OK)
 			return SR_ERR;
+		state->trigger_slope = idx;
 		ret = SR_OK;
 		break;
 	case SR_CONF_TRIGGER_PATTERN:
@@ -378,13 +378,13 @@ static int config_set(uint32_t key, GVariant *data,
 			return SR_ERR_ARG;
 		if ((j = std_cg_idx(cg, devc->analog_groups, model->analog_channels)) < 0)
 			return SR_ERR_ARG;
-		state->analog_channels[j].coupling = idx;
 		g_snprintf(command, sizeof(command),
 			   (*model->scpi_dialect)[SCPI_CMD_SET_COUPLING],
 			   j + 1, (*model->coupling_options)[idx]);
 		if (sr_scpi_send(sdi->conn, command) != SR_OK ||
 		    sr_scpi_get_opc(sdi->conn) != SR_OK)
 			return SR_ERR;
+		state->analog_channels[j].coupling = idx;
 		ret = SR_OK;
 		break;
 	case SR_CONF_LOGIC_THRESHOLD: