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Fix prewrite callbacks' cargo list update for in-place update

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When updating in-place (old==new), we must not write through new
before we're done reading the same memory through old.

Bug: we write the carrier uids too early.  Cargo lists aren't updated
when a carrier dies in an in-place update.  No such updates are known.
Broken in commit 64a53c90, v4.3.17.
This commit is contained in:
Markus Armbruster 2011-07-10 15:36:24 +02:00
parent 91c2ecec53
commit a8b7d1d017
3 changed files with 34 additions and 21 deletions
Download patch file Download diff file Expand all files Collapse all files

21
src/lib/subs/land.c
View file

@ -64,21 +64,24 @@ lnd_prewrite(int n, void *old, void *new)
struct lndstr *oldlp = old;
struct lndstr *lp = new;
natid own = lp->lnd_effic < LAND_MINEFF ? 0 : lp->lnd_own;
int ship = lp->lnd_ship;
int land = lp->lnd_land;
/* Be careful with writing to *lp, in case oldlp == lp */
if (!own) {
lp->lnd_effic = 0;
lp->lnd_ship = lp->lnd_land = -1;
ship = land = -1;
}
item_prewrite(lp->lnd_item);
if (CANT_HAPPEN(lp->lnd_ship >= 0 && lp->lnd_land >= 0))
lp->lnd_land = -1;
if (oldlp->lnd_ship != lp->lnd_ship)
lnd_carrier_change(lp, EF_SHIP, oldlp->lnd_ship, lp->lnd_ship);
if (oldlp->lnd_land != lp->lnd_land)
lnd_carrier_change(lp, EF_LAND, oldlp->lnd_land, lp->lnd_land);
if (CANT_HAPPEN(ship >= 0 && land >= 0))
land = -1;
if (oldlp->lnd_ship != ship)
lnd_carrier_change(lp, EF_SHIP, oldlp->lnd_ship, ship);
if (oldlp->lnd_land != land)
lnd_carrier_change(lp, EF_LAND, oldlp->lnd_land, land);
/* We've avoided assigning to lp->lnd_own, in case oldlp == lp */
if (oldlp->lnd_own != own) {
lost_and_found(EF_LAND, oldlp->lnd_own, own,
lp->lnd_uid, lp->lnd_x, lp->lnd_y);
@ -87,6 +90,8 @@ lnd_prewrite(int n, void *old, void *new)
}
lp->lnd_own = own;
lp->lnd_ship = ship;
lp->lnd_land = land;
if (!own || lp->lnd_x != oldlp->lnd_x || lp->lnd_y != oldlp->lnd_y)
unit_update_cargo((struct empobj *)lp);
}

13
src/lib/subs/nuke.c
View file

@ -29,7 +29,7 @@
* Known contributors to this file:
* Dave Pare, 1989
* Steve McClure, 1996
* Markus Armbruster, 2006-2008
* Markus Armbruster, 2006-2011
*/
#include <config.h>
@ -60,21 +60,24 @@ nuk_prewrite(int n, void *old, void *new)
struct nukstr *oldnp = old;
struct nukstr *np = new;
natid own = np->nuk_effic == 0 ? 0 : np->nuk_own;
int plane = np->nuk_plane;
/* Be careful with writing to *np, in case oldnp == np */
if (!own) {
np->nuk_effic = 0;
np->nuk_plane = -1;
plane = -1;
}
if (oldnp->nuk_plane != np->nuk_plane)
nuk_carrier_change(np, EF_PLANE, oldnp->nuk_plane, np->nuk_plane);
if (oldnp->nuk_plane != plane)
nuk_carrier_change(np, EF_PLANE, oldnp->nuk_plane, plane);
/* We've avoided assigning to np->nuk_own, in case oldnp == np */
if (oldnp->nuk_own != own)
lost_and_found(EF_NUKE, oldnp->nuk_own, own,
np->nuk_uid, np->nuk_x, np->nuk_y);
np->nuk_own = own;
np->nuk_plane = plane;
}
char *

21
src/lib/subs/plane.c
View file

@ -64,20 +64,23 @@ pln_prewrite(int n, void *old, void *new)
struct plnstr *oldpp = old;
struct plnstr *pp = new;
natid own = pp->pln_effic < PLANE_MINEFF ? 0 : pp->pln_own;
int ship = pp->pln_ship;
int land = pp->pln_land;
/* Be careful with writing to *pp, in case oldpp == pp */
if (!own) {
pp->pln_effic = 0;
pp->pln_ship = pp->pln_land = -1;
ship = land = -1;
}
if (CANT_HAPPEN(pp->pln_ship >= 0 && pp->pln_land >= 0))
pp->pln_land = -1;
if (oldpp->pln_ship != pp->pln_ship)
pln_carrier_change(pp, EF_SHIP, oldpp->pln_ship, pp->pln_ship);
if (oldpp->pln_land != pp->pln_land)
pln_carrier_change(pp, EF_LAND, oldpp->pln_land, pp->pln_land);
if (CANT_HAPPEN(ship >= 0 && land >= 0))
land = -1;
if (oldpp->pln_ship != ship)
pln_carrier_change(pp, EF_SHIP, oldpp->pln_ship, ship);
if (oldpp->pln_land != land)
pln_carrier_change(pp, EF_LAND, oldpp->pln_land, land);
/* We've avoided assigning to pp->pln_own, in case oldpp == pp */
if (oldpp->pln_own != own) {
lost_and_found(EF_PLANE, oldpp->pln_own, own,
pp->pln_uid, pp->pln_x, pp->pln_y);
@ -86,6 +89,8 @@ pln_prewrite(int n, void *old, void *new)
}
pp->pln_own = own;
pp->pln_ship = ship;
pp->pln_land = land;
if (!own || pp->pln_x != oldpp->pln_x || pp->pln_y != oldpp->pln_y)
unit_update_cargo((struct empobj *)pp);
}