Return error messages as 'const char *', not 'char *'.

They're never dynamically allocated, and are almost always string
literals, so const is more appropriate.

1 files changed, 3 insertions, 3 deletions

diff --git a/twiddle.c b/twiddle.c
index 70f768d..fb8f700 100644
--- a/twiddle.c
+++ b/twiddle.c
@@ -201,7 +201,7 @@ static game_params *custom_params(const config_item *cfg)
     return ret;
 }
 
-static char *validate_params(const game_params *params, int full)
+static const char *validate_params(const game_params *params, int full)
 {
     if (params->n < 2)
 	return "Rotating block size must be at least two";
@@ -422,7 +422,7 @@ static char *new_game_desc(const game_params *params, random_state *rs,
     return ret;
 }
 
-static char *validate_desc(const game_params *params, const char *desc)
+static const char *validate_desc(const game_params *params, const char *desc)
 {
     const char *p;
     int w = params->w, h = params->h, wh = w*h;
@@ -533,7 +533,7 @@ static int compare_int(const void *av, const void *bv)
 }
 
 static char *solve_game(const game_state *state, const game_state *currstate,
-                        const char *aux, char **error)
+                        const char *aux, const char **error)
 {
     return dupstr("S");
 }