config.h: idempotent-wrap the generated config.h

[ccan] / tools / configurator / configurator.c

diff --git a/tools/configurator/configurator.c b/tools/configurator/configurator.c
index 4445139c90fcfabd01989956e1e60cd8cc958e36..b150dadb56d99f9e21bb4702b1f9af0e3e943bb6 100644 (file)
--- a/tools/configurator/configurator.c
+++ b/tools/configurator/configurator.c
@@ -44,6 +44,9 @@ static struct test tests[] = {
          "static int __attribute__((const)) func(int x) { return x; }" },
        { "HAVE_ATTRIBUTE_MAY_ALIAS", OUTSIDE_MAIN, NULL,
          "typedef short __attribute__((__may_alias__)) short_a;" },
+       { "HAVE_ATTRIBUTE_NORETURN", DEFINES_FUNC, NULL,
+         "#include <stdlib.h>\n"
+         "static void __attribute__((noreturn)) func(int x) { exit(x); }" },
        { "HAVE_ATTRIBUTE_PRINTF", DEFINES_FUNC, NULL,
          "static void __attribute__((format(__printf__, 1, 2))) func(const char *fmt, ...) { }" },
        { "HAVE_ATTRIBUTE_UNUSED", OUTSIDE_MAIN, NULL,
@@ -334,10 +337,13 @@ int main(int argc, char *argv[])
        unlink(INPUT_FILE);
 
        cmd[strlen(cmd) - strlen(" -o " OUTPUT_FILE " " INPUT_FILE)] = '\0';
-       printf("/* Generated by CCAN configurator */\n");
+       printf("#ifndef CCAN_CONFIG_H\n"
+              "#define CCAN_CONFIG_H\n"
+              "/* Generated by CCAN configurator */\n");
        printf("#define CCAN_COMPILER \"%s\"\n", argv[1]);
        printf("#define CCAN_CFLAGS \"%s\"\n\n", cmd + strlen(argv[1]) + 1);
        for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
                printf("#define %s %u\n", tests[i].name, tests[i].answer);
+       printf("#endif /* CCAN_CONFIG_H */\n");
        return 0;
 }