Plug memory leaks in mission execution code

Mission execution first builds lists of eligible units, one list per
country.  These lists are passed to perform_mission() one by one,
where they get freed.

Bugs:

* unit_interdict() didn't pass the list for the submarine's owner, but
  build_mission_list_type() built one.  Any submarine movement within
  own submarine interdiction mission op areas leaked memory.

* dosupport() passed only lists for countries that actually support
  (ally at war with victim), but build_mission_list_type() built lists
  for all countries hostile to the victim.  Ground combat within
  support mission op areas countries that are hostile to one of the
  party without actually supporting the other leaked memory.

* perform_mission() failed to free missiles targeting units.

Fixing the latter is straightforward.

Fix the first two by deciding whether a country acts on a mission
trigger before building any lists, in ground_interdict(),
unit_interdict(), dosupport().  Remove the code dealing with that from
build_mission_list_type() and the loops around perform_mission().

src/lib/subs/mission.c

@@ -63,9 +63,11 @@ struct airport {
 static void add_airport(struct emp_qelem *, coord, coord);
 static int air_damage(struct emp_qelem *, coord, coord, int, natid,
 		      char *, int);
-static void build_mission_list(struct genlist *, coord, coord, int, natid);
+static void build_mission_list(struct genlist[],
-static void build_mission_list_type(struct genlist *, coord, coord, int,
+			       unsigned char[], unsigned char[],
-				    int, natid);
+			       coord, coord, int);
+static void build_mission_list_type(struct genlist[], unsigned char[],
+				    coord, coord, int, int);
 static void divide(struct emp_qelem *, struct emp_qelem *, coord, coord);
 static int dosupport(coord, coord, natid, natid, int);
 static int find_airport(struct emp_qelem *, coord, coord);
@@ -96,20 +98,20 @@ int
 ground_interdict(coord x, coord y, natid victim, char *s)
 {
     int cn;
-    int dam = 0, newdam, rel;
+    int dam = 0, newdam;
+    unsigned char act[MAXNOC];
     struct genlist mi[MAXNOC];
 
     memset(mi, 0, sizeof(mi));
-    for (cn = 1; cn < MAXNOC; cn++)
+    act[0] = 0;
+    for (cn = 1; cn < MAXNOC; cn++) {
+	act[cn] = getrel(getnatp(cn), victim) <= HOSTILE;
 	emp_initque((struct emp_qelem *)&mi[cn]);
+    }
 
-    build_mission_list(mi, x, y, MI_INTERDICT, victim);
+    build_mission_list(mi, act, act, x, y, MI_INTERDICT);
 
     for (cn = 1; cn < MAXNOC; cn++) {
-	rel = getrel(getnatp(cn), victim);
-	if (rel > HOSTILE)
-	    continue;
-
 	if (QEMPTY(&mi[cn].queue))
 	    continue;
 
@@ -177,25 +179,24 @@ int
 unit_interdict(coord x, coord y, natid victim, char *s, int hardtarget,
 	       int mission)
 {
-    int cn, newdam, osubs;
+    int cn, rel, newdam, osubs;
     int dam = -1;
+    unsigned char plane_act[MAXNOC], other_act[MAXNOC];
     struct genlist mi[MAXNOC];
 
     memset(mi, 0, sizeof(mi));
-    for (cn = 1; cn < MAXNOC; cn++)
+    other_act[0] = plane_act[0] = 0;
+    for (cn = 1; cn < MAXNOC; cn++) {
+	rel = getrel(getnatp(cn), victim);
+	other_act[cn] = rel <= HOSTILE;
+	plane_act[cn] = mission == MI_SINTERDICT
+	    ? cn != victim && rel <= NEUTRAL : other_act[cn];
 	emp_initque((struct emp_qelem *)&mi[cn]);
+    }
 
-    build_mission_list(mi, x, y, mission, victim);
+    build_mission_list(mi, other_act, plane_act, x, y, mission);
 
     for (cn = 1; cn < MAXNOC; cn++) {
-	if (cn == victim)
-	    continue;
-	if (mission == MI_SINTERDICT) {
-	    if (getrel(getnatp(cn), victim) >= FRIENDLY)
-		continue;
-	} else if (getrel(getnatp(cn), victim) > HOSTILE)
-	    continue;
-
 	if (QEMPTY(&mi[cn].queue))
 	    continue;
 
@@ -234,25 +235,24 @@ static int
 dosupport(coord x, coord y, natid victim, natid actee, int mission)
 {
     int cn;
+    unsigned char act[MAXNOC];
     struct genlist mi[MAXNOC];
-    int rel, newdam;
+    int newdam;
     int dam = 0;
 
     memset(mi, 0, sizeof(mi));
-    for (cn = 1; cn < MAXNOC; cn++)
+    act[0] = 0;
+    for (cn = 1; cn < MAXNOC; cn++) {
+	act[cn] = (cn == actee
+		   || (getrel(getnatp(cn), actee) == ALLIED
+		       && getrel(getnatp(cn), victim) == AT_WAR));
 	emp_initque((struct emp_qelem *)&mi[cn]);
+    }
 
-    build_mission_list(mi, x, y, MI_SUPPORT, victim);
+    build_mission_list(mi, act, act, x, y, MI_SUPPORT);
-    build_mission_list(mi, x, y, mission, victim);
+    build_mission_list(mi, act, act, x, y, mission);
 
     for (cn = 1; cn < MAXNOC; cn++) {
-	rel = getrel(getnatp(cn), actee);
-	if ((cn != actee) && (rel != ALLIED))
-	    continue;
-	rel = getrel(getnatp(cn), victim);
-	if ((cn != actee) && (rel != AT_WAR))
-	    continue;
-
 	if (QEMPTY(&mi[cn].queue))
 	    continue;
 
@@ -265,29 +265,29 @@ dosupport(coord x, coord y, natid victim, natid actee, int mission)
 }
 
 static void
-build_mission_list(struct genlist *mi, coord x, coord y, int mission,
+build_mission_list(struct genlist mi[],
-		   natid victim)
+		   unsigned char other_act[], unsigned char plane_act[],
+		   coord x, coord y, int mission)
 {
-    build_mission_list_type(mi, x, y, mission, EF_LAND, victim);
+    build_mission_list_type(mi, other_act, x, y, mission, EF_LAND);
-    build_mission_list_type(mi, x, y, mission, EF_SHIP, victim);
+    build_mission_list_type(mi, other_act, x, y, mission, EF_SHIP);
-    build_mission_list_type(mi, x, y, mission, EF_PLANE, victim);
+    build_mission_list_type(mi, plane_act, x, y, mission, EF_PLANE);
 }
 
 static void
-build_mission_list_type(struct genlist *mi, coord x, coord y, int mission,
+build_mission_list_type(struct genlist mi[], unsigned char act[],
-			int type, natid victim)
+			coord x, coord y, int mission, int type)
 {
     struct nstr_item ni;
     struct genlist *glp;
     struct empobj *gp;
     union empobj_storage item;
-    int relat;
 
     snxtitem_all(&ni, type);
     while (nxtitem(&ni, &item)) {
 	gp = (struct empobj *)&item;
 
-	if (gp->own == 0)
+	if (!act[gp->own])
 	    continue;
 
 	if (gp->mobil < 1)
@@ -300,15 +300,6 @@ build_mission_list_type(struct genlist *mi, coord x, coord y, int mission,
 	    (gp->mission != MI_INTERDICT))
 	    continue;
 
-	relat = getrel(getnatp(gp->own), victim);
-	if (mission == MI_SINTERDICT) {
-	    if (relat >= FRIENDLY)
-		continue;
-	    else if (type != EF_PLANE && relat > HOSTILE)
-		continue;
-	} else if (relat > HOSTILE)
-	    continue;
-
 	if (!in_oparea(gp, x, y))
 	    continue;
 
@@ -371,11 +362,11 @@ perform_mission(coord x, coord y, natid victim, struct emp_qelem *list,
 				       targeting_ships);
 	} else if (glp->thing->ef_type == EF_PLANE) {
 	    pcp = &plchr[glp->thing->type];
-	    if (pcp->pl_flags & P_M)
+	    if ((pcp->pl_flags & P_M)
-		/* units have their own missile interdiction */
+		&& (hardtarget != SECT_HARDTARGET
-		if (hardtarget != SECT_HARDTARGET || pcp->pl_flags & P_MAR)
+		    || (pcp->pl_flags & P_MAR)))
-		    continue;
+		;      /* units have their own missile interdiction */
-
+	    else {
 		/* save planes for later */
 		plp = malloc(sizeof(struct plist));
 
@@ -386,6 +377,7 @@ perform_mission(coord x, coord y, natid victim, struct emp_qelem *list,
 		    emp_insque(&plp->queue, &missiles);
 		else
 		    emp_insque(&plp->queue, &bombers);
+	    }
 	} else {
 	    CANT_REACH();
 	    break;