Introduce test library in util/test.h containing the die() function

Fix the die() function to exit with EXIT_FAILURE value as pointed
out by Kalle on elinks-dev in <87tzqkxhlp.fsf@Astalo.kon.iki.fi>.

src/dom/test/dom-select.c

@@ -15,21 +15,7 @@
 #include "dom/select.h"
 #include "dom/sgml/parser.h"
 #include "dom/stack.h"
-
-
-void die(const char *msg, ...)
-{
-	va_list args;
-
-	if (msg) {
-		va_start(args, msg);
-		vfprintf(stderr, msg, args);
-		fputs("\n", stderr);
-		va_end(args);
-	}
-
-	exit(!!NULL);
-}
+#include "util/test.h"
 
 int
 main(int argc, char *argv[])

src/dom/test/sgml-parser.c

@@ -16,6 +16,7 @@
 #include "dom/sgml/dump.h"
 #include "dom/sgml/parser.h"
 #include "dom/stack.h"
+#include "util/test.h"
 
 
 unsigned int number_of_lines = 0;
@@ -242,21 +243,6 @@ sgml_error_function(struct sgml_parser *parser, struct dom_string *string,
 	return DOM_CODE_OK;
 }
 
-static void
-die(const char *msg, ...)
-{
-	va_list args;
-
-	if (msg) {
-		va_start(args, msg);
-		vfprintf(stderr, msg, args);
-		fputs("\n", stderr);
-		va_end(args);
-	}
-
-	exit(!!NULL);
-}
-
 static int
 get_opt(char **argref, const char *name, int *argi, int argc, char *argv[],
 	const char *expect_msg)

src/mime/backend/mailcap.c

@@ -678,6 +678,9 @@ struct module mailcap_mime_module = struct_module(
 );
 
 #ifdef TEST_MAILCAP
+
+#include "util/test.h"
+
 /* Some ugly shortcuts for getting defined symbols to work. */
 int default_mime_backend,
     install_signal_handler,
@@ -685,20 +688,6 @@ int default_mime_backend,
     program;
 LIST_OF(struct terminal) terminals;
 
-void die(const char *msg, ...)
-{
-	va_list args;
-
-	if (msg) {
-		va_start(args, msg);
-		vfprintf(stderr, msg, args);
-		fputs("\n", stderr);
-		va_end(args);
-	}
-
-	exit(1);
-}
-
 int
 main(int argc, char *argv[])
 {

src/protocol/ftp/ftp-parser.c

@@ -13,21 +13,7 @@
 
 #include "osdep/stat.h"
 #include "protocol/ftp/parse.h"
-
-
-void die(const char *msg, ...)
-{
-	va_list args;
-
-	if (msg) {
-		va_start(args, msg);
-		vfprintf(stderr, msg, args);
-		fputs("\n", stderr);
-		va_end(args);
-	}
-
-	exit(!!NULL);
-}
+#include "util/test.h"
 
 int
 main(int argc, char *argv[])

src/protocol/test/stub.c

@@ -13,6 +13,7 @@
 #include "main/module.h"
 #include "protocol/user.h"
 #include "session/session.h"
+#include "util/test.h"
 
 #define STUB_MODULE(name)				\
 	struct module name = struct_module(		\
@@ -38,21 +39,6 @@ STUB_MODULE(smb_protocol_module);
 STUB_MODULE(uri_rewrite_module);
 STUB_MODULE(user_protocol_module);
 
-static void
-die(const char *msg, ...)
-{
-	va_list args;
-
-	if (msg) {
-		va_start(args, msg);
-		vfprintf(stderr, msg, args);
-		fputs("\n", stderr);
-		va_end(args);
-	}
-
-	exit(!!NULL);
-}
-
 static void
 stub_called(const unsigned char *fun)
 {

src/util/test.h

@@ -0,0 +1,23 @@
+/* Test library */
+
+#ifndef EL__UTIL_TEST_H
+#define EL__UTIL_TEST_H
+
+#include <stdlib.h>
+
+static inline void
+die(const char *msg, ...)
+{
+	va_list args;
+
+	if (msg) {
+		va_start(args, msg);
+		vfprintf(stderr, msg, args);
+		fputs("\n", stderr);
+		va_end(args);
+	}
+
+	exit(EXIT_FAILURE);
+}
+
+#endif