Fix getpath() not to crash when path exceeds MAX_PATH_LEN

[empserver] / src / lib / subs / paths.c

diff --git a/src/lib/subs/paths.c b/src/lib/subs/paths.c
index a14e835ee1f70922b808c3b4ca8d8bd3b7932f19..4a95ed38739e98cdb4e6dfe3609393783e98588a 100644 (file)
--- a/src/lib/subs/paths.c
+++ b/src/lib/subs/paths.c
@@ -1,6 +1,6 @@
 /*
  *  Empire - A multi-player, client/server Internet based war game.
- *  Copyright (C) 1986-2006, Dave Pare, Jeff Bailey, Thomas Ruschak,
+ *  Copyright (C) 1986-2010, Dave Pare, Jeff Bailey, Thomas Ruschak,
  *                           Ken Stevens, Steve McClure
  *
  *  This program is free software; you can redistribute it and/or modify
@@ -26,14 +26,15 @@
  *  ---
  *
  *  path.c: Routines associated with paths, directions, etc.
- * 
+ *
  *  Known contributors to this file:
- *   
+ *     Markus Armbruster, 2005-2009
  */
 
 #include <config.h>
 
 #include "file.h"
+#include "optlist.h"
 #include "path.h"
 #include "player.h"
 #include "prototypes.h"
@@ -57,11 +58,11 @@ direrr(char *stop_msg, char *view_msg, char *map_msg)
     pr(" %c %c\n", dirch[DIR_UL], dirch[DIR_UR]);
     pr("%c   %c\n", dirch[DIR_L], dirch[DIR_R]);
     pr(" %c %c\n", dirch[DIR_DL], dirch[DIR_DR]);
-    if (stop_msg != 0)
+    if (stop_msg)
        pr(stop_msg, dirch[DIR_STOP]);
-    if (view_msg != 0)
+    if (view_msg)
        pr(view_msg, dirch[DIR_VIEW]);
-    if (map_msg != 0)
+    if (map_msg)
        pr(map_msg, dirch[DIR_MAP]);
 }
 
@@ -108,8 +109,6 @@ getpath(char *buf, char *arg, coord x, coord y, int onlyown,
     }
 
     getsect(x, y, &sect);
-    nx = x;
-    ny = y;
 
   more:
     while (*p) {
@@ -120,10 +119,10 @@ getpath(char *buf, char *arg, coord x, coord y, int onlyown,
                pr("Destination sectors not allowed here!\n");
                break;
            case P_FLYING:
-               bp = BestAirPath(buf2, nx, ny, dx, dy);
+               bp = BestAirPath(buf2, x, y, dx, dy);
                break;
            case P_SAILING:
-               bp = BestShipPath(buf2, nx, ny, dx, dy, player->cnum);
+               bp = BestShipPath(buf2, x, y, dx, dy, player->cnum);
                break;
            }
            if (bp && p + strlen(bp) + 1 < buf + MAX_PATH_LEN) {
@@ -151,13 +150,13 @@ getpath(char *buf, char *arg, coord x, coord y, int onlyown,
               xyas(nx, ny, player->cnum));
            break;
        }
-       if (dir == DIR_STOP || dir == DIR_MAP) {
+       if (dir == DIR_STOP) {
            p[1] = 0;
            return buf;
        }
        ++p;
-       x = nx;
-       y = ny;
+       x = sect.sct_x;
+       y = sect.sct_y;
     }
     fly_map(x, y);
     if (showdes) {
@@ -169,13 +168,13 @@ getpath(char *buf, char *arg, coord x, coord y, int onlyown,
                xyas(x, y, player->cnum));
     }
     bp = getstring(prompt, buf2);
-    if (bp && p + strlen(bp) + 1 >= buf + MAX_PATH_LEN) {
+    if (!bp)
+       return NULL;
+    if (p + strlen(bp) + 1 >= buf + MAX_PATH_LEN) {
        pr("Path length may not exceed %d.\n", MAX_PATH_LEN);
        pr("Aborting...\n");
-       bp = NULL;
-    }
-    if (!bp)
        return NULL;
+    }
     strcpy(p, bp);
     if (*bp)
        goto more;
@@ -237,32 +236,34 @@ pathtoxy(char *path, coord *xp, coord *yp,
 void
 pathrange(coord cx, coord cy, char *pp, int border, struct range *range)
 {
-    int dir;
+    int dir, lx, ly, hx, hy;
 
-    range->lx = cx;
-    range->hx = cx;
-    range->ly = cy;
-    range->hy = cy;
-    range->width = 0;
-    range->height = 0;
+    lx = hx = cx;
+    ly = hy = cy;
     for (; *pp; pp++) {
        dir = diridx(*pp);
        if (dir == DIR_STOP)
            break;
        cx += diroff[dir][0];
        cy += diroff[dir][1];
-       if (cx < range->lx)
-           range->lx = cx;
-       if (cx > range->hx)
-           range->hx = cx;
-       if (cy < range->ly)
-           range->ly = cy;
-       if (cy > range->hy)
-           range->hy = cy;
+       if (cx < lx)
+           lx = cx;
+       if (cx > hx)
+           hx = cx;
+       if (cy < ly)
+           ly = cy;
+       if (cy > hy)
+           hy = cy;
     }
-    range->lx = xnorm(range->lx - border * 2);
-    range->ly = ynorm(range->ly - border);
-    range->hx = xnorm(range->hx + border * 2 + 1);
-    range->hy = ynorm(range->hy + border + 1);
+
+    lx -= border * 2;
+    hx += border * 2;
+    ly -= border;
+    hy += border;
+
+    range->lx = xnorm(lx);
+    range->hx = ynorm(hx - lx < WORLD_X ? hx : lx - 1);
+    range->ly = ynorm(ly);
+    range->hy = ynorm(hy - ly < WORLD_Y ? hy : ly - 1);
     xysize_range(range);
 }