1 files changed, 121 insertions, 2 deletions
diff --git a/difftimeval.c b/difftimeval.c
index 9ba06c5..0cd8cda 100644
--- a/difftimeval.c
+++ b/difftimeval.c
@@ -1,9 +1,10 @@
 /* See LICENSE file for copyright and license details. */
 #include "libsimple.h"
+#ifndef TEST
 
 
 int
-libsimple_difftimeval(struct timeval *diff, const struct timeval *minuend, const struct timeval *subtrahend) /* TODO test */
+libsimple_difftimeval(struct timeval *diff, const struct timeval *minuend, const struct timeval *subtrahend)
 {
 	struct timespec a, b, d;
 	int r;
@@ -12,5 +13,123 @@ libsimple_difftimeval(struct timeval *diff, const struct timeval *minuend, const
 	r = libsimple_difftimespec(&d, &a, &b);
 	if (r && errno != ERANGE)
 		return r;
-	return r | libsimple_timespec2timeval(diff, &d);
+	if (libsimple_timespec2timeval(diff, &d) && r)
+		errno = ERANGE;
+	return r;
 }
+
+
+#else
+#include "test.h"
+
+int
+main(void)
+{
+	struct timeval r, a, b;
+
+	a.tv_sec = 0, a.tv_usec = 0L;
+	b.tv_sec = 0, b.tv_usec = 0L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == 0);
+	assert(r.tv_usec == 0L);
+
+	a.tv_sec = 10, a.tv_usec = 0L;
+	b.tv_sec =  0, b.tv_usec = 0L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == 10);
+	assert(r.tv_usec == 0L);
+
+	a.tv_sec = 10, a.tv_usec = 100L;
+	b.tv_sec =  0, b.tv_usec =   0L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == 10);
+	assert(r.tv_usec == 100L);
+
+	a.tv_sec = 10, a.tv_usec = 100L;
+	b.tv_sec =  1, b.tv_usec =   0L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == 9);
+	assert(r.tv_usec == 100L);
+
+	a.tv_sec = 10, a.tv_usec = 100L;
+	b.tv_sec =  0, b.tv_usec =   1L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == 10);
+	assert(r.tv_usec == 99L);
+
+	a.tv_sec = -10, a.tv_usec = 100L;
+	b.tv_sec =   0, b.tv_usec =   0L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == -10);
+	assert(r.tv_usec == 100L);
+
+	a.tv_sec = 10, a.tv_usec =   1L;
+	b.tv_sec =  1, b.tv_usec = 100L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == 8);
+	assert(r.tv_usec == 1000001L - 100L);
+
+	a.tv_sec = 10, a.tv_usec = 0L;
+	b.tv_sec = 20, b.tv_usec = 0L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == -10);
+	assert(r.tv_usec == 0L);
+
+	a.tv_sec = 10, a.tv_usec = 10L;
+	b.tv_sec = 20, b.tv_usec =  0L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == -10);
+	assert(r.tv_usec == 10L);
+
+	a.tv_sec = 10, a.tv_usec = 10L;
+	b.tv_sec = 20, b.tv_usec = 20L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == -10 - 1);
+	assert(r.tv_usec == 1000010L - 20L);
+
+	a.tv_sec =  10, a.tv_usec = 10L;
+	b.tv_sec = -20, b.tv_usec =  0L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == 30);
+	assert(r.tv_usec == 10L);
+
+	a.tv_sec = 0, a.tv_usec = 10L;
+	b.tv_sec = 0, b.tv_usec =  0L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == 0);
+	assert(r.tv_usec == 10L);
+
+	a.tv_sec = 0, a.tv_usec =  0L;
+	b.tv_sec = 0, b.tv_usec = 10L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == -1);
+	assert(r.tv_usec == 1000000L - 10L);
+
+	a.tv_sec = TIME_MIN, a.tv_usec = 0L;
+	b.tv_sec = 0,        b.tv_usec = 0L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == TIME_MIN);
+	assert(r.tv_usec == 0L);
+
+	a.tv_sec = TIME_MIN, a.tv_usec = 0L;
+	b.tv_sec = 0,        b.tv_usec = 1L;
+	assert(libsimple_difftimeval(&r, &a, &b) == -1 && errno == ERANGE);
+	assert(r.tv_sec  == TIME_MIN);
+	assert(r.tv_usec == 0L);
+
+	a.tv_sec = TIME_MIN, a.tv_usec = 0L;
+	b.tv_sec = -1,       b.tv_usec = 1L;
+	assert(!libsimple_difftimeval(&r, &a, &b));
+	assert(r.tv_sec  == TIME_MIN);
+	assert(r.tv_usec == 999999L);
+
+	a.tv_sec = TIME_MAX, a.tv_usec = 0L;
+	b.tv_sec = -1,       b.tv_usec = 0L;
+	assert(libsimple_difftimeval(&r, &a, &b) == -1 && errno == ERANGE);
+	assert(r.tv_sec  == TIME_MAX);
+	assert(r.tv_usec == 999999L);
+
+	return 0;
+}
+
+#endif