From 515a9171523f7d8aa85f2caab262ba7d6320c33c Mon Sep 17 00:00:00 2001
From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 21 Sep 2011 12:12:54 -0700
Subject: [PATCH] Add helper function for doing depth unit calculations

.. and use it for printing too.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 dive.c    | 25 +++++++++++++++++++++++++
 dive.h    |  2 ++
 print.c   |  9 ++++++---
 profile.c | 18 ++++--------------
 4 files changed, 37 insertions(+), 17 deletions(-)

diff --git a/dive.c b/dive.c
index 1b906ee43..41bbabd69 100644
--- a/dive.c
+++ b/dive.c
@@ -5,6 +5,31 @@
 
 #include "dive.h"
 
+double get_depth_units(unsigned int mm, int *frac, const char **units)
+{
+	int decimals;
+	double d;
+	const char *unit;
+
+	switch (output_units.length) {
+	case METERS:
+		d = mm / 1000.0;
+		unit = "m";
+		decimals = d < 20;
+		break;
+	case FEET:
+		d = mm_to_feet(mm);
+		unit = "ft";
+		decimals = 0;
+		break;
+	}
+	if (frac)
+		*frac = decimals;
+	if (units)
+		*units = unit;
+	return d;
+}
+
 struct dive *alloc_dive(void)
 {
 	const int initial_samples = 5;
diff --git a/dive.h b/dive.h
index 85fdabf5d..fc458d04d 100644
--- a/dive.h
+++ b/dive.h
@@ -86,6 +86,8 @@ typedef struct {
 	pressure_t start, end;
 } cylinder_t;
 
+extern double get_depth_units(unsigned int mm, int *frac, const char **units);
+
 static inline double mm_to_feet(int mm)
 {
 	return mm * 0.00328084;
diff --git a/print.c b/print.c
index 8d3bc6150..704ecaf66 100644
--- a/print.c
+++ b/print.c
@@ -26,7 +26,9 @@ static void set_font(PangoLayout *layout, PangoFontDescription *font, double siz
  */
 static void show_dive_text(struct dive *dive, cairo_t *cr, double w, double h, PangoFontDescription *font)
 {
-	int len, width, height, maxwidth, maxheight;
+	double depth;
+	const char *unit;
+	int len, decimals, width, height, maxwidth, maxheight;
 	PangoLayout *layout;
 	struct tm *tm;
 	char buffer[1024], divenr[20];
@@ -64,11 +66,12 @@ static void show_dive_text(struct dive *dive, cairo_t *cr, double w, double h, P
 	 * with the depth/duration information. Need to mask that or
 	 * create a box or something.
 	 */
+	depth = get_depth_units(dive->maxdepth.mm, &decimals, &unit);
 	snprintf(buffer, sizeof(buffer),
-		"Max depth: %d ft\n"
+		"Max depth: %.*f %s\n"
 		"Duration: %d:%02d\n"
 		"%s",
-		to_feet(dive->maxdepth),
+		decimals, depth, unit,
 		dive->duration.seconds / 60,
 		dive->duration.seconds % 60,
 		dive->buddy ? :"");
diff --git a/profile.c b/profile.c
index 3f3dd42bc..1b7db1d90 100644
--- a/profile.c
+++ b/profile.c
@@ -158,22 +158,12 @@ static void plot_text(struct graphics_context *gc, const text_render_options_t *
 
 static void render_depth_sample(struct graphics_context *gc, struct plot_data *entry, const text_render_options_t *tro)
 {
-	int sec = entry->sec;
-	depth_t depth = { entry->val };
-	const char *fmt;
+	int sec = entry->sec, decimals;
 	double d;
 
-	switch (output_units.length) {
-	case METERS:
-		d = depth.mm / 1000.0;
-		fmt = "%.1f";
-		break;
-	case FEET:
-		d = to_feet(depth);
-		fmt = "%.0f";
-		break;
-	}
-	plot_text(gc, tro, sec, depth.mm, fmt, d);
+	d = get_depth_units(entry->val, &decimals, NULL);
+
+	plot_text(gc, tro, sec, entry->val, "%.*f", decimals, d);
 }
 
 static void plot_text_samples(struct graphics_context *gc, struct plot_info *pi)