From: Gerhard Sittig <redacted>
Date: Sun, 15 Jul 2018 18:11:58 +0000 (+0200)
Subject: output: simplify trigger marker position calculation (readability)
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=3387a5d8ee7d28cd5927ce36d21765bc051ea175;p=libsigrok.git

output: simplify trigger marker position calculation (readability)

This amends commit 67b345b981a5 which fixed the calculation of the
trigger marker's position. Improve readability of the formulae and
adjust comments.
---

diff --git a/src/output/ascii.c b/src/output/ascii.c
index 3962fe9d..9e04e768 100644
--- a/src/output/ascii.c
+++ b/src/output/ascii.c
@@ -200,10 +200,9 @@ static int receive(const struct sr_output *o, const struct sr_datafeed_packet *p
 					g_string_append_c(*out, '\n');
 					if (j == ctx->num_enabled_channels - 1 && ctx->trigger > -1) {
 						/*
-						 * Each group of 8 bits occupies 8 bit positions
-						 * and no separator. With this dense presentation
-						 * the "calculation" of the trigger position is
-						 * rather straight forward.
+						 * Sample data lines have one character per bit and
+						 * no separator between bytes. Align trigger marker
+						 * to this layout.
 						 */
 						offset = ctx->trigger;
 						g_string_append_printf(*out, "T:%*s^ %d\n", offset, "", ctx->trigger);
diff --git a/src/output/bits.c b/src/output/bits.c
index 379f019b..c3f2ef32 100644
--- a/src/output/bits.c
+++ b/src/output/bits.c
@@ -169,13 +169,11 @@ static int receive(const struct sr_output *o, const struct sr_datafeed_packet *p
 					g_string_append_c(*out, '\n');
 					if (j == ctx->num_enabled_channels - 1 && ctx->trigger > -1) {
 						/*
-						 * Each group of 8 bits occupies 8 bit positions
-						 * plus 1 separator. Calculate the position of the
-						 * byte which contains the trigger, then adjust for
-						 * the trigger's bit position within that byte.
+						 * Sample data lines have one character per bit,
+						 * plus one separator per byte. Align trigger marker
+						 * to this layout.
 						 */
-						offset = ctx->trigger / 8 * (8 + 1);
-						offset += ctx->trigger % 8;
+						offset = ctx->trigger + ctx->trigger / 8;
 						g_string_append_printf(*out, "T:%*s^ %d\n", offset, "", ctx->trigger);
 						ctx->trigger = -1;
 					}
diff --git a/src/output/hex.c b/src/output/hex.c
index 89111446..a1c09f81 100644
--- a/src/output/hex.c
+++ b/src/output/hex.c
@@ -182,13 +182,11 @@ static int receive(const struct sr_output *o, const struct sr_datafeed_packet *p
 					g_string_append_c(*out, '\n');
 					if (j == ctx->num_enabled_channels - 1 && ctx->trigger > -1) {
 						/*
-						 * Each group of 8 bits occupies 2 hex digits plus
-						 * 1 separator. Calculate the position of the byte
-						 * which contains the trigger, then adjust for the
-						 * trigger's bit position within that byte.
+						 * Sample data lines have one character per nibble,
+						 * plus one separator per byte. Align trigger marker
+						 * to this layout.
 						 */
-						offset = ctx->trigger / 8 * (2 + 1);
-						offset += (ctx->trigger % 8) / 4;
+						offset = ctx->trigger / 4 + ctx->trigger / 8;
 						g_string_append_printf(*out, "T:%*s^ %d\n", offset, "", ctx->trigger);
 						ctx->trigger = -1;
 					}