--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/util.c	Wed Nov 25 21:13:03 2020 +0100
@@ -0,0 +1,146 @@
+/*
+ * util.c -- various utilities
+ *
+ * Copyright (c) 2020 David Demelier <markand@malikania.fr>
+ * 
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <ctype.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdnoreturn.h>
+#include <string.h>
+#include <time.h>
+
+#include "image.h"
+#include "config.h"
+#include "util.h"
+
+noreturn void
+die(const char *fmt, ...)
+{
+	assert(fmt);
+
+	va_list ap;
+
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+
+	exit(1);
+}
+
+char *
+estrdup(const char *str)
+{
+	assert(str);
+
+	char *ret;
+	size_t length = strlen(str);
+
+	if (!(ret = calloc(1, length + 1)))
+		die(strerror(errno));
+
+	return strcpy(ret, str);
+}
+
+void *
+ememdup(const void *src, size_t length)
+{
+	assert(src);
+	assert(length > 0);
+
+	void *ptr;
+
+	if (!(ptr = malloc(length)))
+		die(strerror(errno));
+
+	return memcpy(ptr, src, length);
+}
+
+const char *
+bprintf(const char *fmt, ...)
+{
+	assert(fmt);
+
+	static char buf[BUFSIZ];
+	va_list ap;
+
+	va_start(ap, fmt);
+	vsnprintf(buf, sizeof (buf), fmt, ap);
+	va_end(ap);
+
+	return buf;
+}
+
+const char *
+bstrftime(const char *fmt, const struct tm *tm)
+{
+	assert(fmt);
+	assert(tm);
+
+	static char buf[BUFSIZ];
+
+	strftime(buf, sizeof (buf), fmt, tm);
+
+	return buf;
+}
+
+const char *
+path(const char *filename)
+{
+	assert(filename);
+
+	/* Build path to the template file. */
+	static char path[PATH_MAX];
+
+	snprintf(path, sizeof (path), "%s/%s", config.themedir, filename);
+
+	return path;
+}
+
+void
+replace(char **dst, const char *s)
+{
+	assert(dst);
+	assert(s);
+
+	/* Trim leading spaces. */
+	while (*s && isspace(*s))
+		s++;
+
+	if (*s) {
+		free(*dst);
+		*dst = estrdup(s);
+	}
+}
+
+const char *
+ttl(time_t timestamp, long long int duration)
+{
+	const time_t now = time(NULL);
+	const long long int left = duration - difftime(now, timestamp);
+
+	if (left < IMAGE_DURATION_HOUR)
+		return bprintf("%lld minute(s)", left / 60);
+	if (left < IMAGE_DURATION_DAY)
+		return bprintf("%lld hour(s)", left / 3600);
+
+	/* Other in days. */
+	return bprintf("%lld day(s)", left / 86400);
+}