crypto/hkdf_sha256: new module.

[ccan] / ccan / opt / opt.h

diff --git a/ccan/opt/opt.h b/ccan/opt/opt.h
index f891002fa53890be40251b3e2557c4af3d2cd15e..0d508cf6fd173d1578bf26d1a703c3b12bbf3643 100644 (file)
--- a/ccan/opt/opt.h
+++ b/ccan/opt/opt.h
@@ -185,7 +185,7 @@ void opt_register_table(const struct opt_table *table, const char *desc);
  * string (or see opt_set_alloc) and return false.
  *
  * Example:
- * static char *explode(const char *optarg, void *unused)
+ * static char *explode(const char *optarg, void *unused UNNEEDED)
  * {
  *     errx(1, "BOOM! %s", optarg);
  * }
@@ -372,6 +372,22 @@ char *opt_invalid_argument(const char *arg);
  */
 char *opt_usage(const char *argv0, const char *extra);
 
+/**
+ * opt_usage_exit_fail - complain about bad usage to stderr, exit with status 1.
+ * @msg...: printf-style message to output.
+ *
+ * This prints argv[0] (if opt_parse has been called), a colon, then
+ * the message to stderr (just like errx()).  Then it prints out the
+ * usage message, taken from any registered option which uses
+ * opt_usage_and_exit() as described in opt_usage(argv0, NULL) above.
+ * Then it exits with status 1.
+ *
+ * Example:
+ *     if (argc != 5)
+ *             opt_usage_exit_fail("Need 5 arguments, only got %u", argc);
+ */
+void opt_usage_exit_fail(const char *msg, ...) NORETURN;
+
 /**
  * opt_hidden - string for undocumented options.
  *
@@ -450,8 +466,9 @@ void opt_show_ulonglongval_si(char buf[OPT_SHOW_LEN], const unsigned long long *
 
 
 
-/* Increment. */
+/* Increment and decrement. */
 char *opt_inc_intval(int *i);
+char *opt_dec_intval(int *i);
 
 /* Display version string to stdout, exit(0). */
 char *opt_version_and_exit(const char *version);