opt: allow show callbacks to return false.

[ccan] / ccan / opt / opt.h

diff --git a/ccan/opt/opt.h b/ccan/opt/opt.h
index 9c9f337d0a61685bf301883b9a5d1d01bb93a82b..e0331be264230cb57a100f30e26a6f119bf6ca6c 100644 (file)
--- a/ccan/opt/opt.h
+++ b/ccan/opt/opt.h
@@ -47,9 +47,10 @@ struct opt_table;
  * where "type" is the type of the @arg argument.  The first argument to the
  * @cb is the argument found on the commandline.
  *
- * Similarly, if @show is not NULL, it should be of type "void show(char *,
- * size_t len, const type *)".  It should write up to len bytes into the first
- * argument; unless it uses the entire len bytes it should nul-terminate that
+ * Similarly, if @show is not NULL, it should be of type "bool show(char *,
+ * size_t len, const type *)".  If there is no default, it should return false,
+ * otherwise it should write up to len bytes into the first argument and
+ * return true; unless it uses the entire len bytes it should nul-terminate that
  * buffer.
  *
  * Any number of equivalent short or long options can be listed in @names,
@@ -434,32 +435,33 @@ extern const char opt_hidden[];
 char *opt_set_bool(bool *b);
 /* Sets @b based on arg: (yes/no/true/false). */
 char *opt_set_bool_arg(const char *arg, bool *b);
-void opt_show_bool(char *buf, size_t len, const bool *b);
+bool opt_show_bool(char *buf, size_t len, const bool *b);
 /* The inverse */
 char *opt_set_invbool(bool *b);
-void opt_show_invbool(char *buf, size_t len, const bool *b);
+bool opt_show_invbool(char *buf, size_t len, const bool *b);
 /* Sets @b based on !arg: (yes/no/true/false). */
 char *opt_set_invbool_arg(const char *arg, bool *b);
 
 /* Set a char *. */
 char *opt_set_charp(const char *arg, char **p);
-void opt_show_charp(char *buf, size_t len, char *const *p);
+/* If *p is NULL, this returns false (i.e. doesn't show a default) */
+bool opt_show_charp(char *buf, size_t len, char *const *p);
 
 /* Set an integer value, various forms.  Sets to 1 on arg == NULL. */
 char *opt_set_intval(const char *arg, int *i);
-void opt_show_intval(char *buf, size_t len, const int *i);
+bool opt_show_intval(char *buf, size_t len, const int *i);
 char *opt_set_uintval(const char *arg, unsigned int *ui);
-void opt_show_uintval(char *buf, size_t len, const unsigned int *ui);
+bool opt_show_uintval(char *buf, size_t len, const unsigned int *ui);
 char *opt_set_longval(const char *arg, long *l);
-void opt_show_longval(char *buf, size_t len, const long *l);
+bool opt_show_longval(char *buf, size_t len, const long *l);
 char *opt_set_ulongval(const char *arg, unsigned long *ul);
-void opt_show_ulongval(char *buf, size_t len, const unsigned long *ul);
+bool opt_show_ulongval(char *buf, size_t len, const unsigned long *ul);
 
 /* Set an floating point value, various forms. */
 char *opt_set_floatval(const char *arg, float *f);
-void opt_show_floatval(char *buf, size_t len, const float *f);
+bool opt_show_floatval(char *buf, size_t len, const float *f);
 char *opt_set_doubleval(const char *arg, double *d);
-void opt_show_doubleval(char *buf, size_t len, const double *d);
+bool opt_show_doubleval(char *buf, size_t len, const double *d);
 
 /* the following setting functions accept k, M, G, T, P, or E suffixes, which
    multiplies the numeric value by the corresponding power of 1000 or 1024
@@ -479,19 +481,19 @@ char *opt_set_ulonglongval_bi(const char *arg, unsigned long long *ll);
 char *opt_set_ulonglongval_si(const char *arg, unsigned long long *ll);
 
 
-void opt_show_intval_bi(char *buf, size_t len, const int *x);
-void opt_show_longval_bi(char *buf, size_t len, const long *x);
-void opt_show_longlongval_bi(char *buf, size_t len, const long long *x);
-void opt_show_uintval_bi(char *buf, size_t len, const unsigned int *x);
-void opt_show_ulongval_bi(char *buf, size_t len, const unsigned long *x);
-void opt_show_ulonglongval_bi(char *buf, size_t len, const unsigned long long *x);
+bool opt_show_intval_bi(char *buf, size_t len, const int *x);
+bool opt_show_longval_bi(char *buf, size_t len, const long *x);
+bool opt_show_longlongval_bi(char *buf, size_t len, const long long *x);
+bool opt_show_uintval_bi(char *buf, size_t len, const unsigned int *x);
+bool opt_show_ulongval_bi(char *buf, size_t len, const unsigned long *x);
+bool opt_show_ulonglongval_bi(char *buf, size_t len, const unsigned long long *x);
 
-void opt_show_intval_si(char *buf, size_t len, const int *x);
-void opt_show_longval_si(char *buf, size_t len, const long *x);
-void opt_show_longlongval_si(char *buf, size_t len, const long long *x);
-void opt_show_uintval_si(char *buf, size_t len, const unsigned int *x);
-void opt_show_ulongval_si(char *buf, size_t len, const unsigned long *x);
-void opt_show_ulonglongval_si(char *buf, size_t len, const unsigned long long *x);
+bool opt_show_intval_si(char *buf, size_t len, const int *x);
+bool opt_show_longval_si(char *buf, size_t len, const long *x);
+bool opt_show_longlongval_si(char *buf, size_t len, const long long *x);
+bool opt_show_uintval_si(char *buf, size_t len, const unsigned int *x);
+bool opt_show_ulongval_si(char *buf, size_t len, const unsigned long *x);
+bool opt_show_ulonglongval_si(char *buf, size_t len, const unsigned long long *x);
 
 
 
@@ -551,7 +553,7 @@ struct opt_table {
        enum opt_type type;
        char *(*cb)(void *arg); /* OPT_NOARG */
        char *(*cb_arg)(const char *optarg, void *arg); /* OPT_HASARG */
-       void (*show)(char *buf, size_t len, const void *arg);
+       bool (*show)(char *buf, size_t len, const void *arg);
        union {
                const void *carg;
                void *arg;
@@ -577,14 +579,14 @@ struct opt_table {
                          char *(*)(const char *, const typeof(*(arg))*), \
                          char *(*)(const char *, const void *),        \
                          (cb)),                                        \
-       typesafe_cb_cast(void (*)(char *buf, size_t, const void *), \
-                        void (*)(char *buf, size_t, const typeof(*(arg))*), (show))
+       typesafe_cb_cast(bool (*)(char *buf, size_t, const void *), \
+                        bool (*)(char *buf, size_t, const typeof(*(arg))*), (show))
 
 /* Non-typesafe register function. */
 void _opt_register(const char *names, enum opt_type type,
                   char *(*cb)(void *arg),
                   char *(*cb_arg)(const char *optarg, void *arg),
-                  void (*show)(char *buf, size_t len, const void *arg),
+                  bool (*show)(char *buf, size_t len, const void *arg),
                   const void *arg, const char *desc);
 
 /* We use this to get typechecking for OPT_SUBTABLE */