Bugfix/code clean using gcc warnings (#371)

* Enable extra GCC warnings to discover subtle bugs

* convert c++ comments to c comments

* cleanup pedantic compiler warnings

* Compile apps with GNU89 GNU99 GNU11 and GNU17

Co-authored-by: Steve Karg <skarg@users.sourceforge.net>

src/bacnet/basic/sys/bigend.c

@@ -5,7 +5,10 @@
 
 #include "bacnet/basic/sys/bigend.h"
 
-#ifndef BACNET_BIG_ENDIAN
+#ifdef BACNET_BIG_ENDIAN
+/* workaround: warning: ISO C forbids an empty translation unit [-Wpedantic] */
+typedef int make_iso_compilers_happy;
+#else
 /* Big-Endian systems save the most significant byte first.  */
 /* Sun and Motorola processors, IBM-370s and PDP-10s are big-endian. */
 /* "Network Byte Order" is also know as "Big-Endian Byte Order" */

src/bacnet/basic/sys/color_rgb.c

@@ -50,6 +50,8 @@ void color_rgb_to_xy(uint8_t r,
     float *y_coordinate,
     uint8_t *brightness)
 {
+    float X, Y, Z;
+    float x, y;
     /*  Get the RGB values from your color object
         and convert them to be between 0 and 1.
         So the RGB color (255, 0, 100) becomes (1.0, 0.0, 0.39) */
@@ -76,13 +78,13 @@ void color_rgb_to_xy(uint8_t r,
 
     /*  Convert the RGB values to XYZ using the
         Wide RGB D65 conversion formula */
-    float X = red * 0.649926f + green * 0.103455f + blue * 0.197109f;
-    float Y = red * 0.234327f + green * 0.743075f + blue * 0.022598f;
-    float Z = red * 0.0000000f + green * 0.053077f + blue * 1.035763f;
+    X = red * 0.649926f + green * 0.103455f + blue * 0.197109f;
+    Y = red * 0.234327f + green * 0.743075f + blue * 0.022598f;
+    Z = red * 0.0000000f + green * 0.053077f + blue * 1.035763f;
 
     /* Calculate the xy values from the XYZ values */
-    float x = X / (X + Y + Z);
-    float y = Y / (X + Y + Z);
+    x = X / (X + Y + Z);
+    y = Y / (X + Y + Z);
 
     x = clamp(x, 0.0f, 1.0f);
     y = clamp(y, 0.0f, 1.0f);
@@ -122,20 +124,23 @@ void color_rgb_from_xy(uint8_t *red,
     float y_coordinate,
     uint8_t brightness)
 {
+    float r, g, b;
+    float x, y, z, X, Y, Z;
+
     /*  Calculate XYZ values */
-    float x = x_coordinate;
-    float y = y_coordinate;
-    float z = 1.0f - x - y;
-    float Y = (float)brightness;
+    x = x_coordinate;
+    y = y_coordinate;
+    z = 1.0f - x - y;
+    Y = (float)brightness;
     Y /= 255.0f;
-    float X = (Y / y) * x;
-    float Z = (Y / y) * z;
+    X = x * (Y / y);
+    Z = z * (Y / y);
 
     /*  Convert to RGB using Wide RGB D65 conversion
        (THIS IS A D50 conversion currently) */
-    float r = X * 1.4628067f - Y * 0.1840623f - Z * 0.2743606f;
-    float g = -X * 0.5217933f + Y * 1.4472381f + Z * 0.0677227f;
-    float b = X * 0.0349342f - Y * 0.0968930f + Z * 1.2884099f;
+    r = X * 1.4628067f - Y * 0.1840623f - Z * 0.2743606f;
+    g = -X * 0.5217933f + Y * 1.4472381f + Z * 0.0677227f;
+    b = X * 0.0349342f - Y * 0.0968930f + Z * 1.2884099f;
 
     /*  Apply reverse gamma correction */
     r = r <= 0.0031308f ? 12.92f * r

src/bacnet/basic/sys/debug.c

@@ -59,3 +59,59 @@ void debug_printf(const char *format, ...)
     (void)format;
 }
 #endif
+
+#if PRINT_ENABLED
+int debug_aprintf(const char *format, ...)
+{
+    int length = 0;
+    va_list ap;
+
+    va_start(ap, format);
+    length = vfprintf(stdout, format, ap);
+    va_end(ap);
+    fflush(stdout);
+
+    return length;
+}
+
+int debug_fprintf(FILE *stream, const char *format, ...)
+{
+    int length = 0;
+    va_list ap;
+
+    va_start(ap, format);
+    length = vfprintf(stream, format, ap);
+    va_end(ap);
+    fflush(stream);
+
+    return length;
+}
+
+void debug_perror(const char *format, ...)
+{
+    va_list ap;
+
+    va_start(ap, format);
+    vfprintf(stderr, format, ap);
+    va_end(ap);
+    fflush(stderr);
+}
+#else
+int debug_aprintf(const char *format, ...)
+{
+    (void)format;
+    return 0;
+}
+
+int debug_fprintf(FILE *stream, const char *format, ...)
+{
+    (void)stream;
+    (void)format;
+    return 0;
+}
+
+void debug_perror(const char *format, ...)
+{
+    (void)format;
+}
+#endif

src/bacnet/basic/sys/debug.h

@@ -42,6 +42,19 @@ extern "C" {
     void debug_printf(
         const char *format,
         ...);
+    BACNET_STACK_EXPORT
+    int debug_aprintf(
+        const char *format,
+        ...);
+    BACNET_STACK_EXPORT
+    int debug_fprintf(
+        FILE *stream,
+        const char *format,
+        ...);
+    BACNET_STACK_EXPORT
+    void debug_perror(
+        const char *format,
+        ...);
 #if DEBUG_ENABLED
     /* Nothing more here */
 #else

src/bacnet/basic/sys/platform.h

@@ -18,6 +18,12 @@
 #ifndef BACNET_SYS_PLATFORM_H
 #define BACNET_SYS_PLATFORM_H
 
+#include <math.h>
+
+#ifndef islessgreater
+#define islessgreater(x, y) ((x) < (y) || (x) > (y))
+#endif
+
 /* marking some code as 'deprecated' */
 # if defined(_MSC_VER)
 #   define BACNET_STACK_DEPRECATED(message) __declspec(deprecated(message))
@@ -31,4 +37,10 @@
 #  define strcasecmp _stricmp
 # endif
 
+#if defined(__GNUC__)
+#define BACNET_STACK_FALLTHROUGH() __attribute__ ((fallthrough))
+#else 
+#define BACNET_STACK_FALLTHROUGH() /* fall through */
+#endif
+
 #endif