Move fgetline out into misc.c.

I'm about to want to use it outside the GTK front end.

gtk.c

@@ -2886,25 +2886,6 @@ static frontend *new_window(char *arg, int argtype, char **error)
     return fe;
 }
 
-char *fgetline(FILE *fp)
-{
-    char *ret = snewn(512, char);
-    int size = 512, len = 0;
-    while (fgets(ret + len, size - len, fp)) {
-	len += strlen(ret + len);
-	if (ret[len-1] == '\n')
-	    break;		       /* got a newline, we're done */
-	size = len + 512;
-	ret = sresize(ret, size, char);
-    }
-    if (len == 0) {		       /* first fgets returned NULL */
-	sfree(ret);
-	return NULL;
-    }
-    ret[len] = '\0';
-    return ret;
-}
-
 static void list_presets_from_menu(struct preset_menu *menu)
 {
     int i;

misc.c

@@ -169,6 +169,25 @@ unsigned char *hex2bin(const char *in, int outlen)
     return ret;
 }
 
+char *fgetline(FILE *fp)
+{
+    char *ret = snewn(512, char);
+    int size = 512, len = 0;
+    while (fgets(ret + len, size - len, fp)) {
+	len += strlen(ret + len);
+	if (ret[len-1] == '\n')
+	    break;		       /* got a newline, we're done */
+	size = len + 512;
+	ret = sresize(ret, size, char);
+    }
+    if (len == 0) {		       /* first fgets returned NULL */
+	sfree(ret);
+	return NULL;
+    }
+    ret[len] = '\0';
+    return ret;
+}
+
 void game_mkhighlight_specific(frontend *fe, float *ret,
 			       int background, int highlight, int lowlight)
 {

puzzles.h

@@ -357,6 +357,7 @@ char *dupstr(const char *s);
  */
 void free_cfg(config_item *cfg);
 void obfuscate_bitmap(unsigned char *bmp, int bits, int decode);
+char *fgetline(FILE *fp);
 
 /* allocates output each time. len is always in bytes of binary data.
  * May assert (or just go wrong) if lengths are unchecked. */