Add a test of cmdline usage strings - and make them saner
diff --git a/src/core/support/cmdline.c b/src/core/support/cmdline.c
index 72f46c1..530952c 100644
--- a/src/core/support/cmdline.c
+++ b/src/core/support/cmdline.c
@@ -131,33 +131,63 @@
cl->extra_arg_help = help;
}
-static void print_usage_and_die(gpr_cmdline *cl) {
+/* recursively descend argument list, adding the last element
+ to s first - so that arguments are added in the order they were
+ added to the list by api calls */
+static void add_args_to_usage(gpr_strvec *s, arg *a) {
+ char *tmp;
+
+ if (!a) return;
+ add_args_to_usage(s, a->next);
+
+ switch (a->type) {
+ case ARGTYPE_BOOL:
+ gpr_asprintf(&tmp, " [--%s|--no-%s]", a->name, a->name);
+ gpr_strvec_add(s, tmp);
+ break;
+ case ARGTYPE_STRING:
+ gpr_asprintf(&tmp, " [--%s=string]", a->name);
+ gpr_strvec_add(s, tmp);
+ break;
+ case ARGTYPE_INT:
+ gpr_asprintf(&tmp, " [--%s=int]", a->name);
+ gpr_strvec_add(s, tmp);
+ break;
+ }
+}
+
+char *gpr_cmdline_usage_string(gpr_cmdline *cl, const char *argv0) {
/* TODO(ctiller): make this prettier */
- arg *a;
- const char *name = strrchr(cl->argv0, '/');
+ gpr_strvec s;
+ char *tmp;
+ const char *name = strrchr(argv0, '/');
+
if (name) {
name++;
} else {
- name = cl->argv0;
+ name = argv0;
}
- fprintf(stderr, "Usage: %s", name);
- for (a = cl->args; a; a = a->next) {
- switch (a->type) {
- case ARGTYPE_BOOL:
- fprintf(stderr, " [--%s|--no-%s]", a->name, a->name);
- break;
- case ARGTYPE_STRING:
- fprintf(stderr, " [--%s=string]", a->name);
- break;
- case ARGTYPE_INT:
- fprintf(stderr, " [--%s=int]", a->name);
- break;
- }
- }
+
+ gpr_strvec_init(&s);
+
+ gpr_asprintf(&tmp, "Usage: %s", name);
+ gpr_strvec_add(&s, tmp);
+ add_args_to_usage(&s, cl->args);
if (cl->extra_arg) {
- fprintf(stderr, " [%s...]", cl->extra_arg_name);
+ gpr_asprintf(&tmp, " [%s...]", cl->extra_arg_name);
+ gpr_strvec_add(&s, tmp);
}
- fprintf(stderr, "\n");
+ gpr_strvec_add(&s, gpr_strdup("\n"));
+
+ tmp = gpr_strvec_flatten(&s, NULL);
+ gpr_strvec_destroy(&s);
+ return tmp;
+}
+
+static void print_usage_and_die(gpr_cmdline *cl) {
+ char *usage = gpr_cmdline_usage_string(cl, cl->argv0);
+ fprintf(stderr, "%s", usage);
+ gpr_free(usage);
exit(1);
}