From 038c6037190539283beddfab132a27d167c4d969 Mon Sep 17 00:00:00 2001
From: Jef Driesen <jefdriesen@users.sourceforge.net>
Date: Sun, 27 Jan 2013 15:54:50 +0100
Subject: [PATCH] Simplify parsing the variable size gasmix section.

The HelO2, D4i, D6i and D9tx all use the same data format for the gas
mixes. The only difference is the number of gas mixes and the initial
byte offset. With this knowledge, we can easily use the same code for
all models. An additional advantage is that because the profile
configuration data is stored immediately after the gasmix section, we
can also replace the hardcoded offset with a simple calculation.
---
 src/suunto_d9_parser.c | 81 +++++++++++++++++++++++++-----------------
 1 file changed, 49 insertions(+), 32 deletions(-)

diff --git a/src/suunto_d9_parser.c b/src/suunto_d9_parser.c
index 497d4e8..c53422e 100644
--- a/src/suunto_d9_parser.c
+++ b/src/suunto_d9_parser.c
@@ -186,13 +186,31 @@ suunto_d9_parser_get_field (dc_parser_t *abstract, dc_field_type_t type, unsigne
 	const unsigned char *data = abstract->data;
 	unsigned int size = abstract->size;
 
+	// Gasmix information.
+	unsigned int gasmix_offset = 0x21, gasmix_count = 3;
+	if (parser->model == HELO2) {
+		gasmix_offset = 0x54;
+		gasmix_count = 8;
+	} else if (parser->model == D4i) {
+		gasmix_offset = 0x5F;
+		gasmix_count = 1;
+	} else if (parser->model == D6i) {
+		gasmix_offset = 0x5F;
+		gasmix_count = 2;
+	} else if (parser->model == D9tx) {
+		gasmix_offset = 0x87;
+		gasmix_count = 8;
+	}
+
 	// Offset to the configuration data.
 	unsigned int config = 0x3A;
-	if (parser->model == D4)
+	if (parser->model == D4) {
 		config += 1;
-	if (parser->model == HELO2)
-		config = 0x84;
-	if (size < config)
+	} else if (parser->model == HELO2 || parser->model == D4i ||
+		parser->model == D6i || parser->model == D9tx) {
+		config = gasmix_offset + gasmix_count * 6;
+	}
+	if (config + 1 > size)
 		return DC_STATUS_DATAFORMAT;
 
 	// Gas model
@@ -223,34 +241,21 @@ suunto_d9_parser_get_field (dc_parser_t *abstract, dc_field_type_t type, unsigne
 		case DC_FIELD_GASMIX_COUNT:
 			if (gasmodel == AIR) {
 				*((unsigned int *) value) = 1;
-			} else if (parser->model == HELO2) {
-				*((unsigned int *) value) = 8;
-			} else if (parser->model == D9tx) {
-				*((unsigned int *) value) = 8;
-			} else if (parser->model == D6i) {
-				*((unsigned int *) value) = 2;
-			} else if (parser->model == D4i) {
-				*((unsigned int *) value) = 1;
 			} else {
-				*((unsigned int *) value) = 3;
+				*((unsigned int *) value) = gasmix_count;
 			}
 			break;
 		case DC_FIELD_GASMIX:
 			if (gasmodel == AIR) {
 				gasmix->helium = 0.0;
 				gasmix->oxygen = 0.21;
-			} else if (parser->model == HELO2) {
-				gasmix->helium = data[0x54 + 6 * flags + 2] / 100.0;
-				gasmix->oxygen = data[0x54 + 6 * flags + 1] / 100.0;
-			} else if (parser->model == D9tx) {
-				gasmix->helium = data[0x87 + 6 * flags + 2] / 100.0;
-				gasmix->oxygen = data[0x87 + 6 * flags + 1] / 100.0;
-			} else if (parser->model == D4i || parser->model == D6i) {
-				gasmix->helium = data[0x5F + 6 * flags + 2] / 100.0;
-				gasmix->oxygen = data[0x5F + 6 * flags + 1] / 100.0;
+			} else if (parser->model == HELO2 || parser->model == D4i ||
+				parser->model == D6i || parser->model == D9tx) {
+				gasmix->helium = data[gasmix_offset + 6 * flags + 2] / 100.0;
+				gasmix->oxygen = data[gasmix_offset + 6 * flags + 1] / 100.0;
 			} else {
 				gasmix->helium = 0.0;
-				gasmix->oxygen = data[0x21 + flags] / 100.0;
+				gasmix->oxygen = data[gasmix_offset + flags] / 100.0;
 			}
 			gasmix->nitrogen = 1.0 - gasmix->oxygen - gasmix->helium;
 			break;
@@ -274,18 +279,30 @@ suunto_d9_parser_samples_foreach (dc_parser_t *abstract, dc_sample_callback_t ca
 	const unsigned char *data = abstract->data;
 	unsigned int size = abstract->size;
 
+	// Gasmix information.
+	unsigned int gasmix_offset = 0x21, gasmix_count = 3;
+	if (parser->model == HELO2) {
+		gasmix_offset = 0x54;
+		gasmix_count = 8;
+	} else if (parser->model == D4i) {
+		gasmix_offset = 0x5F;
+		gasmix_count = 1;
+	} else if (parser->model == D6i) {
+		gasmix_offset = 0x5F;
+		gasmix_count = 2;
+	} else if (parser->model == D9tx) {
+		gasmix_offset = 0x87;
+		gasmix_count = 8;
+	}
+
 	// Offset to the configuration data.
 	unsigned int config = 0x3A;
-	if (parser->model == D4)
+	if (parser->model == D4) {
 		config += 1;
-	if (parser->model == HELO2)
-		config = 0x84;
-	if (parser->model == D4i)
-		config = 0x65;
-	if (parser->model == D6i)
-		config = 0x6B;
-	if (parser->model == D9tx)
-		config = 0xB7;
+	} else if (parser->model == HELO2 || parser->model == D4i ||
+		parser->model == D6i || parser->model == D9tx) {
+		config = gasmix_offset + gasmix_count * 6;
+	}
 	if (config + 1 > size)
 		return DC_STATUS_DATAFORMAT;