Fixed bug 2274 - SDL_ceil is incorrectly implemented when HAVE_LIBC is not defined
authorSam Lantinga <slouken@libsdl.org>
Wed, 27 Nov 2013 00:29:46 -0800
changeset 8033 8181c3a4a055
parent 8032 e2096994e8b8
child 8034 b80feead1d04
Fixed bug 2274 - SDL_ceil is incorrectly implemented when HAVE_LIBC is not defined Ghassan Al-Mashareqa The SDL_ceil function is implemented incorrectly when HAVE_CEIL is not defined (HAVE_LIBC not defined). The following code: double val = SDL_ceil(2.3); printf("%g", val); prints "2.0", as STD_ceil is defined as: double SDL_ceil(double x) { #ifdef HAVE_CEIL return ceil(x); #else return (double)(int)((x)+0.5); #endif /* HAVE_CEIL */ } This functions is used in the SDL_BuildAudioResampleCVT function of the audio subsystem (SDL_audiocvt.c), and causes a bug in that function.
src/stdlib/SDL_stdlib.c
--- a/src/stdlib/SDL_stdlib.c	Tue Nov 26 11:50:54 2013 -0300
+++ b/src/stdlib/SDL_stdlib.c	Wed Nov 27 00:29:46 2013 -0800
@@ -52,7 +52,12 @@
 #ifdef HAVE_CEIL
     return ceil(x);
 #else
-    return (double)(int)((x)+0.5);
+    double integer = SDL_floor(x);
+    double fraction = x - integer;
+    if (fraction > 0.0) {
+        integer += 1.0;
+    }
+    return integer;
 #endif /* HAVE_CEIL */
 }