time: initial implementation.

6 files changed, 192 insertions, 1 deletions

diff --git a/include/rin/time.h b/include/rin/time.h
new file mode 100644
index 0000000..aa9bc66
--- /dev/null
+++ b/include/rin/time.h
@@ -0,0 +1,36 @@
+/*
+ * The Rin Library – time module
+ *
+ * Copyright (C) 2017 Gediminas Jakutis
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; version 2.1
+ * of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#ifndef LIBRIN_TIME_INCLUDED
+#define LIBRIN_TIME_INCLUDED
+
+#include <time.h>
+
+struct timespec rin_time_add(const struct timespec * const a, const struct timespec * const b);
+struct timespec rin_time_sub(const struct timespec * const a, const struct timespec * const b);
+struct timespec rin_time_normalize(const struct timespec * const t);
+unsigned int rin_time_cmp_less(const struct timespec * const a, const struct timespec * const b);
+unsigned int rin_time_cmp_more(const struct timespec * const a, const struct timespec * const b);
+unsigned int rin_time_cmp_lessequal(const struct timespec * const a, const struct timespec * const b);
+unsigned int rin_time_cmp_moreequal(const struct timespec * const a, const struct timespec * const b);
+unsigned int rin_time_cmp_equal(const struct timespec * const a, const struct timespec * const b);
+unsigned int rin_time_cmp_nonequal(const struct timespec * const a, const struct timespec * const b);
+
+#endif /* LIBRIN_TIME_INCLUDED */
diff --git a/meson_options.txt b/meson_options.txt
index 279996a..b5deb2f 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -4,3 +4,4 @@ option('tests', type : 'boolean', value : false, description : 'Enable building
 option('float', type : 'boolean', value : true, description : 'Enable building the floating point module')
 option('gpio', type : 'boolean', value : true, description : 'Enable building the gpio module')
 option('diagnostic', type : 'boolean', value : true, description : 'Enable building the diagnostics module')
+option('time', type : 'boolean', value : true, description : 'Enable building the time module')
diff --git a/src/meson.build b/src/meson.build
index 1d98b67..8bd83b7 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -1,6 +1,7 @@
 subdir('float')
 subdir('gpio')
 subdir('diagnostic')
+subdir('time')
 
-sources = [float_sources, gpio_sources, diagnostic_sources]
+sources = [float_sources, gpio_sources, diagnostic_sources, time_sources]
 
diff --git a/src/time/meson.build b/src/time/meson.build
new file mode 100644
index 0000000..93c1a4d
--- /dev/null
+++ b/src/time/meson.build
@@ -0,0 +1,10 @@
+if get_option('time')
+	time_filenames = [
+		'time.c',
+		'time_private.h',
+	]
+else
+	time_filenames = []
+endif
+
+time_sources = files(time_filenames)
diff --git a/src/time/time.c b/src/time/time.c
new file mode 100644
index 0000000..2c87cba
--- /dev/null
+++ b/src/time/time.c
@@ -0,0 +1,117 @@
+/*
+ * The Rin Library – time module
+ *
+ * Copyright (C) 2017 Gediminas Jakutis
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; version 2.1
+ * of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#include "rin/time.h"
+#include "time_private.h"
+
+struct timespec rin_time_add(const struct timespec * const a, const struct timespec * const b)
+{
+	struct timespec ret;
+
+	ret.tv_sec = a->tv_sec + b->tv_sec;
+	ret.tv_nsec = a->tv_nsec + b->tv_nsec;
+
+	return rin_time_normalize(&ret);
+}
+
+struct timespec rin_time_sub(const struct timespec * const a, const struct timespec * const b)
+{
+	struct timespec ret;
+
+	ret.tv_sec = a->tv_sec - b->tv_sec;
+	ret.tv_nsec = a->tv_nsec - b->tv_nsec;
+
+	return rin_time_normalize(&ret);
+}
+
+struct timespec rin_time_normalize(const struct timespec * const t)
+{
+	struct timespec ret;
+
+	ret = *t;
+
+	if (ret.tv_nsec >= 0 && ret.tv_nsec <= tv_nsec_max) {
+		return ret;
+	}
+
+	if (ret.tv_nsec > 0) {
+		ret.tv_sec += ret.tv_nsec / tv_nsec_max;
+		ret.tv_nsec = ret.tv_nsec % tv_nsec_max;
+	} else {
+		ret.tv_sec += ret.tv_nsec / tv_nsec_max - 1;
+		ret.tv_nsec = tv_nsec_max - ret.tv_nsec % tv_nsec_max;
+	}
+
+	return ret;
+
+}
+unsigned int rin_time_cmp_less(const struct timespec * const a, const struct timespec * const b)
+{
+	if (a->tv_sec > b->tv_sec) {
+		return 0;
+	} else if (a->tv_sec < b->tv_sec) {
+		return 1;
+	} else {
+		return a->tv_nsec < b->tv_nsec;
+	}
+}
+
+unsigned int rin_time_cmp_more(const struct timespec * const a, const struct timespec * const b)
+{
+	if (a->tv_sec < b->tv_sec) {
+		return 0;
+	} else if (a->tv_sec > b->tv_sec) {
+		return 1;
+	} else {
+		return a->tv_nsec > b->tv_nsec;
+	}
+}
+
+unsigned int rin_time_cmp_lessequal(const struct timespec * const a, const struct timespec * const b)
+{
+	if (a->tv_sec > b->tv_sec) {
+		return 0;
+	} else if (a->tv_sec < b->tv_sec) {
+		return 1;
+	} else {
+		return a->tv_nsec <= b->tv_nsec;
+	}
+}
+
+unsigned int rin_time_cmp_moreequal(const struct timespec * const a, const struct timespec * const b)
+{
+	if (a->tv_sec < b->tv_sec) {
+		return 0;
+	} else if (a->tv_sec > b->tv_sec) {
+		return 1;
+	} else {
+		return a->tv_nsec >= b->tv_nsec;
+	}
+}
+
+unsigned int rin_time_cmp_equal(const struct timespec * const a, const struct timespec * const b)
+{
+	return a->tv_sec == b->tv_sec && a->tv_nsec == b->tv_nsec;
+}
+
+unsigned int rin_time_cmp_nonequal(const struct timespec * const a, const struct timespec * const b)
+{
+	return a->tv_sec != b->tv_sec || a->tv_sec != b->tv_nsec;
+}
diff --git a/src/time/time_private.h b/src/time/time_private.h
new file mode 100644
index 0000000..4bb6099
--- /dev/null
+++ b/src/time/time_private.h
@@ -0,0 +1,26 @@
+/*
+ * The Rin Library – time module
+ *
+ * Copyright (C) 2017 Gediminas Jakutis
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; version 2.1
+ * of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#ifndef LIBRIN_TIME_PRIVATE_INCLUDED
+#define LIBRIN_TIME_PRIVATE_INCLUDED
+
+static const long tv_nsec_max = 999999999l;
+
+#endif /* LIBRIN_TIME_PRIVATE_INCLUDED */