math: add dummy tgamma and tgammaf implementations

2 files changed, 32 insertions, 0 deletions

diff --git a/src/math/tgamma.c b/src/math/tgamma.c
new file mode 100644
index 00000000..f3bbe370
--- /dev/null
+++ b/src/math/tgamma.c
@@ -0,0 +1,16 @@
+#include <math.h>
+
+// FIXME: use lanczos approximation
+
+double __lgamma_r(double, int *);
+
+double tgamma(double x)
+{
+	int sign;
+	double y;
+
+	y = exp(__lgamma_r(x, &sign));
+	if (sign < 0)
+		y = -y;
+	return y;
+}
diff --git a/src/math/tgammaf.c b/src/math/tgammaf.c
new file mode 100644
index 00000000..16df8076
--- /dev/null
+++ b/src/math/tgammaf.c
@@ -0,0 +1,16 @@
+#include <math.h>
+
+// FIXME: use lanczos approximation
+
+float __lgammaf_r(float, int *);
+
+float tgammaf(float x)
+{
+	int sign;
+	float y;
+
+	y = exp(__lgammaf_r(x, &sign));
+	if (sign < 0)
+		y = -y;
+	return y;
+}