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, 5 insertions, 4 deletions

diff --git a/map.c b/map.c
index 917c525..4796f8e 100644
--- a/map.c
+++ b/map.c
@@ -248,7 +248,7 @@ 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->w < 2 || params->h < 2)
 	return "Width and height must be at least two";
@@ -1776,7 +1776,7 @@ static char *parse_edge_list(const game_params *params, const char **desc,
     return NULL;
 }
 
-static char *validate_desc(const game_params *params, const char *desc)
+static const char *validate_desc(const game_params *params, const char *desc)
 {
     int w = params->w, h = params->h, wh = w*h, n = params->n;
     int area;
@@ -2186,7 +2186,7 @@ static void free_game(game_state *state)
 }
 
 static char *solve_game(const game_state *state, const game_state *currstate,
-                        const char *aux, char **error)
+                        const char *aux, const char **error)
 {
     if (!aux) {
 	/*
@@ -3235,7 +3235,8 @@ int main(int argc, char **argv)
 {
     game_params *p;
     game_state *s;
-    char *id = NULL, *desc, *err;
+    char *id = NULL, *desc;
+    const char *err;
     int grade = FALSE;
     int ret, diff, really_verbose = FALSE;
     struct solver_scratch *sc;