From: Markus Armbruster Date: Mon, 11 Feb 2008 22:14:04 +0000 (+0100) Subject: Fix confused and buggy bridge splashing code X-Git-Tag: v4.3.12~178 X-Git-Url: http://git.pond.sub.org/?p=empserver;a=commitdiff_plain;h=40eb78eb74474597b79d05c4a5934ff02fb9e127 Fix confused and buggy bridge splashing code A bridge (span or tower) must be splashed when it gets damaged below SCT_MINEFF. Likewise when its last supporting sector (bridge head or tower) gets damaged below SCT_MINEFF, unless EASY_BRIDGES is enabled. We need to check this whenever a bridge head, span or tower gets damaged. This is done in three places, and all of them screw up: * checksect() ignores damage to bridge heads. It also leaves writing back the sector it checks to the caller, which never happens when it's called from sct_postread(). Note that checksect() drowns all planes on bridges it splashes. Functions that need to exempt flying planes from such a fate have to splash bridges themselves. * sect_damage() ignores damage to bridge towers, and damage to bridge spans unless EASY_BRIDGES is enabled. It then runs checksect(), which compensates for these omissions, but happily drowns the planes sect_damage() attempts to protect. * eff_bomb() ignores damage to bridge heads. Collateral damage makes sect_damage() run, which compensates for the omission. This causes the following bugs: * Efficiency damage going through sect_damage() can drown planes it shouldn't. This affects pinpoint bombing when collateral damage splashes a bridge, and strategic bombing. The drowned planes then crash and burn when they attempt to land at their (just splashed) base. * Efficiency damage to bridge heads not going through sect_damage() fails to collapse unsupported bridges. This affects pin-bombing efficiency without collateral damage, and ground combat. Also deity commands edit, setsector and add, but that could be regarded as a feature. * If the sector file somehow ends up with an inefficient bridge span, it collapses on every read again and again, until it collapses on a write. Related problems exist with other actions of checksect(), and they're not addressed here. * If the sector file somehow ends up with adjacent inefficient bridge towers, checksect() on any of them recurses infinitely: - checksect() inefficient tower T1 - knockdown() T1, but don't write that back to the sector file - bridgefall() T1; this reads all adjacent sectors, including inefficient towert T2 - checksect() T2 - knockdown() T2, but don't write that back to the sector file - bridgefall() T1; this reads adjacent sectors including T1 - checksect() T1 ... This commit creates a new function bridge_damaged() to splash any bridges that became inefficient or unsupported after damage to a sector. To avoid the inifinite recursion, we call it in sct_prewrite() instead of checksect(). No uses knockdown() outside bridgefall.c remain, so give it internal linkage. --- diff --git a/include/prototypes.h b/include/prototypes.h index 6c170c174..5b8ea6959 100644 --- a/include/prototypes.h +++ b/include/prototypes.h @@ -402,8 +402,8 @@ extern void stop_service(void); extern int confirm(char *); extern int askyn(char *); /* bridgefall.c */ +extern void bridge_damaged(struct sctstr *, struct emp_qelem *); extern void bridgefall(struct sctstr *, struct emp_qelem *); -extern void knockdown(struct sctstr *, struct emp_qelem *); /* bsanct.c */ extern void bsanct(void); /* caploss.c */ diff --git a/src/lib/commands/bomb.c b/src/lib/commands/bomb.c index 4afac17e1..72e4f1f95 100644 --- a/src/lib/commands/bomb.c +++ b/src/lib/commands/bomb.c @@ -369,14 +369,7 @@ eff_bomb(struct emp_qelem *list, struct sctstr *target) "%s bombing raid did %d%% damage in %s\n", cname(player->cnum), oldeff - target->sct_effic, xyas(target->sct_x, target->sct_y, target->sct_own)); - if (target->sct_effic < SCT_MINEFF) { - if (target->sct_type == SCT_BSPAN) - knockdown(target, list); - else if (target->sct_type == SCT_BTOWER) { - knockdown(target, list); - bridgefall(target, list); - } - } + bridge_damaged(target, list); putsect(§); collateral_damage(target->sct_x, target->sct_y, dam, list); } diff --git a/src/lib/subs/bridgefall.c b/src/lib/subs/bridgefall.c index c11529d1e..160bd3167 100644 --- a/src/lib/subs/bridgefall.c +++ b/src/lib/subs/bridgefall.c @@ -48,6 +48,31 @@ #include "sect.h" #include "xy.h" +static void knockdown(struct sctstr *, struct emp_qelem *); + +/* + * Check bridges at and around SP after damage to SP. + * If SP is an inefficent bridge, splash it. + * If SP can't support a bridge, splash unsupported adjacent bridges. + * Don't drown planes in LIST when splashing bridges. + * Write back splashed bridges, except for SP; writing that one is + * left to the caller. + */ +void +bridge_damaged(struct sctstr *sp, struct emp_qelem *list) +{ + int des; + + if (sp->sct_effic >= SCT_MINEFF) + return; + + des = sp->sct_type; + if (des == SCT_BSPAN || des == SCT_BTOWER) + knockdown(sp, list); + if ((des == SCT_BHEAD || des == SCT_BTOWER) && !opt_EASY_BRIDGES) + bridgefall(sp, list); +} + void bridgefall(struct sctstr *sp, struct emp_qelem *list) { @@ -94,7 +119,7 @@ bridgefall(struct sctstr *sp, struct emp_qelem *list) /* Knock down a bridge span. Note that this does NOT write the * sector out to the database, it's up to the caller to do that. */ -void +static void knockdown(struct sctstr *sp, struct emp_qelem *list) { struct lndstr land; diff --git a/src/lib/subs/sect.c b/src/lib/subs/sect.c index 52f22f1e3..febaaae1e 100644 --- a/src/lib/subs/sect.c +++ b/src/lib/subs/sect.c @@ -70,6 +70,7 @@ sct_prewrite(int id, void *ptr) time(&sp->sct_timestamp); + bridge_damaged(sp, NULL); checksect(sp); getsect(sp->sct_x, sp->sct_y, §); return 1; @@ -106,14 +107,6 @@ checksect(struct sctstr *sp) else loyalcivs = 0; - if (sp->sct_effic < SCT_MINEFF) { - if (sp->sct_type == SCT_BSPAN) - knockdown(sp, 0); - else if (sp->sct_type == SCT_BTOWER) { - knockdown(sp, 0); - bridgefall(sp, 0); - } - } if (sp->sct_own != 0 && !civs) { sp->sct_work = 100; sp->sct_oldown = sp->sct_own; diff --git a/src/lib/subs/sectdamage.c b/src/lib/subs/sectdamage.c index 6dcacbb70..a14dad48b 100644 --- a/src/lib/subs/sectdamage.c +++ b/src/lib/subs/sectdamage.c @@ -69,13 +69,7 @@ sect_damage(struct sctstr *sp, int dam, struct emp_qelem *list) if (sp->sct_mobil > 0) sp->sct_mobil = damage(sp->sct_mobil, dam); item_damage(dam, sp->sct_item); - if (opt_EASY_BRIDGES == 0) { - if (sp->sct_effic < SCT_MINEFF && sp->sct_type == SCT_BHEAD) - bridgefall(sp, list); - } else { - if (sp->sct_effic < SCT_MINEFF && sp->sct_type == SCT_BSPAN) - knockdown(sp, list); - } + bridge_damaged(sp, list); putsect(sp); return eff; }