resize buffer in eval_command, it was too small for many commands.

increase MAXTEACHERS.
eliminate oldterrain warning in json_report.

src/jsreport.c

@@ -59,11 +59,13 @@ static int report_json(const char *filename, report_context * ctx, const char *c
                             if (sr) {
                                 terrain_t ter = oldterrain(r->terrain);
                                 if (ter == NOTERRAIN) {
-                                    log_warning("report_json: %s has no terrain id\n", r->terrain->_name);
+                                    data = 1 + r->terrain->_name[0];
                                 }
+                                else {
                                     data = 1 + (int)ter;
                                 }
                             }
+                        }
                         fprintf(F, "%d", data);
                         if (x != maxx || y != maxy) fputs(", ", F);
                     }

src/kernel/order.c

@@ -115,7 +115,9 @@ char* get_command(const order *ord, char *sbuffer, size_t size) {
             assert(str);
             if (text) --size;
             bytes = (int)strlcpy(bufp, str, size);
-            if (wrptr(&bufp, &size, bytes) != 0) WARN_STATIC_BUFFER();
+            if (wrptr(&bufp, &size, bytes) != 0) {
+                WARN_STATIC_BUFFER();
+            }
             if (text) *bufp++ = ' ';
         }
         else {

src/kernel/terrain.c

@@ -127,8 +127,7 @@ const struct terrain_type *newterrain(terrain_t t)
 terrain_t oldterrain(const struct terrain_type * terrain)
 {
     terrain_t t;
-    if (terrain == NULL)
-        return NOTERRAIN;
+    assert(terrain);
     for (t = 0; t != MAXTERRAINS; ++t) {
         if (newterrains[t] == terrain)
             return t;

src/reports.c

@@ -2291,7 +2291,7 @@ static void eval_race(struct opstack **stack, const void *userdata)
 static void eval_order(struct opstack **stack, const void *userdata)
 {                               /* order -> string */
     const struct order *ord = (const struct order *)opop(stack).v;
-    char buf[512];
+    char buf[4096];
     size_t len;
     variant var;
 

src/study.c

@@ -222,7 +222,7 @@ bool report, int *academy)
             teach->teachers[index] = NULL;
         }
         else {
-            log_warning("MAXTEACHERS is too low at %d", MAXTEACHERS);
+            log_error("MAXTEACHERS=%d is too low for student %s, teacher %s", MAXTEACHERS, unitname(student), unitname(teacher));
         }
         teach->value += n;
 

src/study.h

@@ -33,7 +33,7 @@ extern "C" {
     extern bool is_migrant(struct unit *u);
     extern int study_cost(struct unit *u, skill_t talent);
 
-#define MAXTEACHERS 16
+#define MAXTEACHERS 20
     typedef struct teaching_info {
         struct unit *teachers[MAXTEACHERS];
         int value;