From: Michael Tremer <michael.tremer@ipfire.org>
Date: Thu, 30 Oct 2025 23:20:07 +0000 (+0000)
Subject: graphs: Automatically convert temperatures to K/C/F
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f1b9daa765fca6972e123e5e649ab6dda9bafa45;p=people%2Fms%2Ftelemetry.git

graphs: Automatically convert temperatures to K/C/F

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/daemon/graph.c b/src/daemon/graph.c
index 267de70..81dcdcd 100644
--- a/src/daemon/graph.c
+++ b/src/daemon/graph.c
@@ -509,6 +509,42 @@ ERROR:
 	return r;
 }
 
+td_graph_temps td_graph_temperature(const td_graph_render_options* options) {
+	// These countries predominantly use Fahrenheit
+	const char* fahrenheit[] = {
+		// United States
+		"en_US",
+		// Bahamas
+		"en_BS",
+		// Belize
+		"en_BZ",
+		// Cayman Islands
+		"en_KY",
+		// Liberia
+		"en_LR",
+		// Palau
+		"en_PW",
+		// Marshall Islands
+		"en_MH",
+		// Micronesia
+		"en_FM",
+		NULL,
+	};
+
+	// If there is no locale, we will use Kelvin
+	if (!options->locale || !*options->locale || td_string_equals(options->locale, "C"))
+		return TD_GRAPH_TEMP_KELVIN;
+
+	// Find anyone using Fahrenheit
+	for (const char** code = fahrenheit; *code; code++) {
+		if (td_string_startswith(options->locale, *code))
+			return TD_GRAPH_TEMP_FAHRENHEIT;
+	}
+
+	// Otherwise use Celsius
+	return TD_GRAPH_TEMP_CELSIUS;
+}
+
 int td_graph_vlabel_bps(td_ctx* ctx, td_graph* graph,
 		const char* object, char* vlabel, size_t length) {
 	return __td_string_set(vlabel, length, _("Bits Per Second"));
diff --git a/src/daemon/graph.h b/src/daemon/graph.h
index e244c3e..a3c4bcb 100644
--- a/src/daemon/graph.h
+++ b/src/daemon/graph.h
@@ -111,6 +111,8 @@ typedef enum td_graph_temps {
 	TD_GRAPH_TEMP_FAHRENHEIT,
 } td_graph_temps;
 
+td_graph_temps td_graph_temperature(const td_graph_render_options* options);
+
 /*
 	Commonly used vlabels
 */
diff --git a/src/daemon/graphs/disk.c b/src/daemon/graphs/disk.c
index 1c129d1..ffec746 100644
--- a/src/daemon/graphs/disk.c
+++ b/src/daemon/graphs/disk.c
@@ -41,7 +41,7 @@ static int disk_temp_render(td_ctx* ctx, td_graph* graph,
 	PRINT_HEADER4(args, _("Current"), _("Average"), _("Minimum"), _("Maximum"));
 
 	// Draw the temperature
-	DRAW_TEMPERATURE_KELVIN(args, "temperature", object, "%s", _("Temperature"));
+	DRAW_TEMPERATURE(args, options, "temperature", object, "%s", _("Temperature"));
 
 	return 0;
 }
diff --git a/src/daemon/graphs/graph.h b/src/daemon/graphs/graph.h
index 13332a4..0875b5b 100644
--- a/src/daemon/graphs/graph.h
+++ b/src/daemon/graphs/graph.h
@@ -76,6 +76,8 @@ typedef enum flags {
 
 // Temperatures
 #define KELVIN			"%%12.2lf K"
+#define CELSIUS			"%%11.2lf °C"
+#define FAHRENHEIT		"%%11.2lf °F"
 
 // Macro to terminate a line
 #define EOL				"\\j"
@@ -233,6 +235,8 @@ static inline int __DRAW(td_args* args, const char* what, const char* field,
 #define FIELD_INF(field)					field "_inf"
 #define FIELD_NEGINF(field)					field "_neginf"
 #define FIELD_BITS(field)					field "_bits"
+#define FIELD_CELSIUS(field)				field "_c"
+#define FIELD_FAHRENHEIT(field)				field "_f"
 
 #define VALUE_CURRENT(args, field, object)	SCRIPT(args, "VDEF:" FIELD_CURRENT(FIELD) "=" FIELD ",LAST", FIELD_AND_OBJECT(field, object), FIELD_AND_OBJECT(field, object))
 #define VALUE_AVERAGE(args, field, object)	SCRIPT(args, "VDEF:" FIELD_AVERAGE(FIELD) "=" FIELD ",AVERAGE", FIELD_AND_OBJECT(field, object), FIELD_AND_OBJECT(field, object))
@@ -286,6 +290,25 @@ static inline int __DRAW(td_args* args, const char* what, const char* field,
 #define COMPUTE_BITS(args, bits, object, bytes)	\
 	COMPUTE_MULTIPLY(args, bits, object, bytes, object, 8)
 
+// Convert Kelvin to Celsius
+#define COMPUTE_CELSIUS(args, field, object) \
+	do { \
+		COMPUTE_CDEF(args, FIELD "=" FIELD ",273.15,-", \
+			FIELD_AND_OBJECT(FIELD_CELSIUS(field), object), \
+			FIELD_AND_OBJECT(field, object) \
+		); \
+		VALUE_ALL(args, FIELD_CELSIUS(field), object); \
+	} while (0)
+
+#define COMPUTE_FAHRENHEIT(args, field, object) \
+	do { \
+		COMPUTE_CDEF(args, FIELD "=" FIELD ",273.15,-,9,*,5,/,32,+", \
+			FIELD_AND_OBJECT(FIELD_FAHRENHEIT(field), object), \
+			FIELD_AND_OBJECT(field, object) \
+		); \
+		VALUE_ALL(args, FIELD_FAHRENHEIT(field), object); \
+	} while (0)
+
 #define COMPUTE_DIVIDE(args, fraction, object1, dividend, object2, divisor) \
 	do { \
 		COMPUTE_CDEF(args, FIELD "=" FIELD "," TOSTRING(divisor) ",/", \
@@ -340,10 +363,41 @@ static inline int __DRAW(td_args* args, const char* what, const char* field,
 /*
 	This draws a temperature graph
 */
-#define DRAW_TEMPERATURE_KELVIN(args, field, object, ...) \
+#define DRAW_TEMPERATURE(args, options, field, object, ...) \
+	do { \
+		switch (td_graph_temperature(options)) { \
+			case TD_GRAPH_TEMP_KELVIN: \
+				DRAW_TEMPERATURE_K(args, field, object, __VA_ARGS__); \
+				break; \
+			\
+			case TD_GRAPH_TEMP_CELSIUS: \
+				DRAW_TEMPERATURE_C(args, field, object, __VA_ARGS__); \
+				break; \
+			\
+			case TD_GRAPH_TEMP_FAHRENHEIT: \
+				DRAW_TEMPERATURE_F(args, field, object, __VA_ARGS__); \
+				break; \
+		} \
+	} while (0)
+
+#define DRAW_TEMPERATURE_K(args, field, object, ...) \
 	do { \
 		DRAW_LINE_WITH_LABEL(args, 1, field, object, COLOR_TEMPERATURE, 0, ##__VA_ARGS__); \
 		PRINT_CAMM(args, field, object, KELVIN); \
 	} while (0)
 
+#define DRAW_TEMPERATURE_C(args, field, object, ...) \
+	do { \
+		COMPUTE_CELSIUS(args, field, object); \
+		DRAW_LINE_WITH_LABEL(args, 1, FIELD_CELSIUS(field), object, COLOR_TEMPERATURE, 0, ##__VA_ARGS__); \
+		PRINT_CAMM(args, FIELD_CELSIUS(field), object, CELSIUS); \
+	} while (0)
+
+#define DRAW_TEMPERATURE_F(args, field, object, ...) \
+	do { \
+		COMPUTE_FAHRENHEIT(args, field, object); \
+		DRAW_LINE_WITH_LABEL(args, 1, FIELD_FAHRENHEIT(field), object, COLOR_TEMPERATURE, 0, ##__VA_ARGS__); \
+		PRINT_CAMM(args, FIELD_FAHRENHEIT(field), object, FAHRENHEIT); \
+	} while (0)
+
 #endif /* TELEMETRY_GRAPHS_GRAPH_H */