Add cutscene skipping to L4D quick reset

Also done with quite a lot of RE help from bill - thanks again!

7 files changed, 298 insertions, 52 deletions

diff --git a/src/dbg.c b/src/dbg.c
index 0db23ec..1c3355b 100644
--- a/src/dbg.c
+++ b/src/dbg.c
@@ -24,9 +24,27 @@
 #include "ppmagic.h"
 #include "udis86.h"
 
+#ifdef _WIN32
+usize dbg_toghidra(const void *addr) {
+	const void *mod;
+	if (!GetModuleHandleExW(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS |
+			GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT, (ushort *)addr,
+			(HMODULE *)&mod /* please leave me alone */)) {
+		con_warn("dbg_toghidra: couldn't get base address\n");
+		return 0;
+	}
+	return (const char *)addr - (const char *)mod + 0x10000000;
+}
+#endif
+
 void dbg_hexdump(const char *name, const void *p, int len) {
 	struct rgba nice_colour = {160, 64, 200, 255}; // a nice purple colour
-	con_colourmsg(&nice_colour, "Hex dump \"%s\" (%p):", name, p);
+#ifdef _WIN32
+	con_colourmsg(&nice_colour, "Hex dump \"%s\" (%p | %p):\n", name, p,
+			(void *)dbg_toghidra(p));
+#else
+	con_colourmsg(&nice_colour, "Hex dump \"%s\" (%p):\n", name, p);
+#endif
 	for (const uchar *cp = p; cp - (uchar *)p < len; ++cp) {
 		// group into words and wrap every 8 words
 		switch ((cp - (uchar *)p) & 31) {
@@ -45,23 +63,15 @@ void dbg_asmdump(const char *name, const void *p, int len) {
 	ud_set_mode(&udis, 32);
 	ud_set_input_buffer(&udis, p, len);
 	ud_set_syntax(&udis, UD_SYN_INTEL);
-	con_colourmsg(&nice_colour, "Disassembly \"%s\" (%p)\n", name, p);
+#ifdef _WIN32
+	con_colourmsg(&nice_colour, "Disassembly \"%s\" (%p | %p):\n", name, p,
+			(void *)dbg_toghidra(p));
+#else
+	con_colourmsg(&nice_colour, "Disassembly \"%s\" (%p):\n", name, p);
+#endif
 	while (ud_disassemble(&udis)) {
 		con_colourmsg(&nice_colour, "  %s\n", ud_insn_asm(&udis));
 	}
 }
 
-#ifdef _WIN32
-usize dbg_toghidra(const void *addr) {
-	const void *mod;
-	if (!GetModuleHandleExW(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS |
-			GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT, (ushort *)addr,
-			(HMODULE *)&mod /* please leave me alone */)) {
-		con_warn("dbg_toghidra: couldn't get base address\n");
-		return 0;
-	}
-	return (const char *)addr - (const char *)mod + 0x10000000;
-}
-#endif
-
 // vi: sw=4 ts=4 noet tw=80 cc=80
diff --git a/src/engineapi.c b/src/engineapi.c
index fe34f64..768510d 100644
--- a/src/engineapi.c
+++ b/src/engineapi.c
@@ -37,6 +37,8 @@ ifacefactory factory_client = 0, factory_server = 0, factory_engine = 0,
 struct VEngineClient *engclient;
 struct VEngineServer *engserver;
 
+void *srvdll;
+
 DECL_VFUNC(void *, GetGlobalVars, 1) // seems to be very stable, thank goodness
 void *globalvars;
 
@@ -47,8 +49,6 @@ DECL_VFUNC_DYN(void *, GetAllServerClasses)
 
 #include <entpropsinit.gen.h> // generated by build/mkentprops.c
 
-static void *srvdll;
-
 bool engineapi_init(int pluginver) {
 	if (!con_detect(pluginver)) return false;
 	pluginhandler = factory_engine("ISERVERPLUGINHELPERS001", 0);
@@ -78,7 +78,7 @@ bool engineapi_init(int pluginver) {
 	vgui = factory_engine("VEngineVGui001", 0);
 
 	// TODO(compat): add this back when there's gamedata for 009 (no point atm)
-	/*if (srvdll = factory_engine("ServerGameDLL009", 0)) {
+	/*if (srvdll = factory_server("ServerGameDLL009", 0)) {
 		_gametype_tag |= _gametype_tag_SrvDLL009;
 	}*/
 	if (srvdll = factory_server("ServerGameDLL005", 0)) {
diff --git a/src/engineapi.h b/src/engineapi.h
index 44366f5..4489e21 100644
--- a/src/engineapi.h
+++ b/src/engineapi.h
@@ -133,6 +133,7 @@ struct ServerClass {
 
 extern struct VEngineClient *engclient;
 extern struct VEngineServer *engserver;
+extern void *srvdll;
 extern void *globalvars;
 extern void *inputsystem, *vgui;
 
diff --git a/src/ent.c b/src/ent.c
index 6329152..261db25 100644
--- a/src/ent.c
+++ b/src/ent.c
@@ -97,12 +97,32 @@ static inline ctor_func findctor(const struct CEntityFactory *factory,
 		const char *classname) {
 #ifdef _WIN32
 	const uchar *insns = (const uchar *)factory->vtable->Create;
-	// every Create() method follows the same pattern. after calling what is
-	// presumably operator new(), it copies the return value from EAX into ECX
-	// and then calls the constructor.
+	// mostly every Create() method follows the same pattern. after calling what
+	// is presumably operator new(), it copies the return value from a register
+	// into ECX and then calls the constructor.
+	//
+	// there have also been some thunky-looking ones, which we attempt to
+	// resolve by following the first call if we bump into a ret before anything
+	// else. this is depth-limited to prevent things getting out of hand.
+	const uchar *seencall = 0;
+	int depth = 3;
 	for (const uchar *p = insns; p - insns < 32;) {
-		if (p[0] == X86_MOVRMW && p[1] == 0xC8 && p[2] == X86_CALL) {
-			return (ctor_func)(p + 7 + mem_loadoffset(p + 3));
+		if (!seencall && p[0] == X86_CALL) {
+			seencall = p;
+		}
+		else {
+			if (p[0] == X86_MOVRMW && (p[1] & 0xF8) == 0xC8
+					&& p[2] == X86_CALL) {
+				return (ctor_func)(p + 7 + mem_loadoffset(p + 3));
+			}
+			if (p[0] == X86_RET || p[0] == X86_RETI16) {
+				if (seencall && --depth) {
+					p = seencall + 5 + mem_loadoffset(seencall + 1); insns = p;
+					seencall = 0;
+					continue;
+				}
+				return false;
+			}
 		}
 		// duping NEXT_INSN macro here in the name of a nicer message
 		int len = x86_len(p);
@@ -127,7 +147,7 @@ void **ent_findvtable(const struct CEntityFactory *factory,
 	const uchar *insns = (const uchar *)ctor;
 	// the constructor itself should do *(void**)this = &vtable; almost right
 	// away, so look for the first immediate load into indirect register
-	for (const uchar *p = insns; p - insns < 24;) {
+	for (const uchar *p = insns; p - insns < 32;) {
 		if (p[0] == X86_MOVMIW && (p[1] & 0xF8) == 0) return mem_loadptr(p + 2);
 		int len = x86_len(p);
 		if (len == -1) {
diff --git a/src/l4dmm.c b/src/l4dmm.c
index d391584..2439d6b 100644
--- a/src/l4dmm.c
+++ b/src/l4dmm.c
@@ -54,6 +54,7 @@ static union { // space saving
 #define oldmmiface U.oldmmiface
 #define sym_game U.sym_game
 #define sym_campaign U.sym_campaign
+static int sym_chapter;
 static char campaignbuf[32];
 
 const char *l4dmm_curcampaign(void) {
@@ -61,16 +62,15 @@ const char *l4dmm_curcampaign(void) {
 	if (!matchfwk) { // we must have oldmmiface, then
 		struct contextval *ctxt = unknown_contextlookup(oldmmiface,
 				"CONTEXT_L4D_CAMPAIGN");
-		if (ctxt) {
-			// HACK: since this context symbol stuff was the best that was found
-			// for this old MM interface, just map things back to their names
-			// manually. bit stupid, but it gets the (rather difficult) job done
-			if (strncmp(ctxt->val, "CONTEXT_L4D_CAMPAIGN_", 21)) return 0;
-			if (!strcmp(ctxt->val + 21, "APARTMENTS")) return "Hospital";
-			if (!strcmp(ctxt->val + 21, "CAVES")) return "SmallTown";
-			if (!strcmp(ctxt->val + 21, "GREENHOUSE")) return "Airport";
-			if (!strcmp(ctxt->val + 21, "HILLTOP")) return "Farm";
-		}
+		if (!ctxt) return 0;
+		// HACK: since this context symbol stuff was the best that was found for
+		// this old MM interface, just map things back to their names manually.
+		// bit stupid, but it gets the (rather difficult) job done
+		if (strncmp(ctxt->val, "CONTEXT_L4D_CAMPAIGN_", 21)) return 0;
+		if (!strcmp(ctxt->val + 21, "APARTMENTS")) return "Hospital";
+		if (!strcmp(ctxt->val + 21, "CAVES")) return "SmallTown";
+		if (!strcmp(ctxt->val + 21, "GREENHOUSE")) return "Airport";
+		if (!strcmp(ctxt->val + 21, "HILLTOP")) return "Farm";
 		return 0;
 	}
 #endif
@@ -94,6 +94,30 @@ const char *l4dmm_curcampaign(void) {
 	return ret;
 }
 
+bool l4dmm_firstmap(void) {
+#ifdef _WIN32
+	if (!matchfwk) { // we must have oldmmiface, then
+		struct contextval *ctxt = unknown_contextlookup(oldmmiface,
+				"CONTEXT_L4D_LEVEL");
+		if (!ctxt) return 0;
+		if (strncmp(ctxt->val, "CONTEXT_L4D_LEVEL_", 18)) return false;
+		return !strcmp(ctxt->val + 18, "APARTMENTS") ||
+				!strcmp(ctxt->val + 18, "CAVES") ||
+				!strcmp(ctxt->val + 18, "GREENHOUSE") ||
+				!strcmp(ctxt->val + 18, "HILLTOP");
+	}
+#endif
+	void *ctrlr = GetMatchNetworkMsgController(matchfwk);
+	struct KeyValues *kv = GetActiveGameServerDetails(ctrlr, 0);
+	if (!kv) return false;
+	int chapter = 0;
+	struct KeyValues *subkey = kvsys_getsubkey(kv, sym_game);
+	if (subkey) subkey = kvsys_getsubkey(subkey, sym_chapter);
+	if (subkey) chapter = subkey->ival;
+	kvsys_free(kv);
+	return chapter == 1;
+}
+
 INIT {
 	void *mmlib = os_dlhandle(OS_LIT("matchmaking") OS_LIT(OS_DLSUFFIX));
 	if (mmlib) {
@@ -109,17 +133,15 @@ INIT {
 		}
 		sym_game = kvsys_strtosym("game");
 		sym_campaign = kvsys_strtosym("campaign");
+		sym_chapter = kvsys_strtosym("chapter");
 	}
+#ifdef _WIN32 // L4D1 has no Linux build, btw!
 	else {
-#ifdef _WIN32
 		oldmmiface = factory_engine("VENGINE_MATCHMAKING_VERSION001", 0);
 		if (!oldmmiface) {
 			errmsg_errorx("couldn't get IMatchmaking interface");
 			return false;
 		}
-#else // Linux L4D1 has always used the separate matchmaking library
-		errmsg_errordl("couldn't get matchmaking library");
-		return false;
 #endif
 	}
 	return true;
diff --git a/src/l4dmm.h b/src/l4dmm.h
index 2897e17..7af0982 100644
--- a/src/l4dmm.h
+++ b/src/l4dmm.h
@@ -27,6 +27,12 @@
  */
 const char *l4dmm_curcampaign(void);
 
+/*
+ * Returns true if the current map is known to be the first map of a campaign,
+ * false otherwise.
+ */
+bool l4dmm_firstmap(void);
+
 #endif
 
 // vi: sw=4 ts=4 noet tw=80 cc=80
diff --git a/src/l4dreset.c b/src/l4dreset.c
index 2245a16..2477b8b 100644
--- a/src/l4dreset.c
+++ b/src/l4dreset.c
@@ -21,12 +21,16 @@
 #include "engineapi.h"
 #include "ent.h"
 #include "errmsg.h"
+#include "event.h"
+#include "fastfwd.h"
 #include "feature.h"
 #include "gamedata.h"
 #include "gametype.h"
+#include "hook.h"
 #include "intdefs.h"
 #include "l4dmm.h"
 #include "mem.h"
+#include "sst.h"
 #include "vcall.h"
 #include "x86.h"
 #include "x86util.h"
@@ -37,12 +41,19 @@
 
 FEATURE("Left 4 Dead quick resetting")
 REQUIRE(ent)
+REQUIRE(fastfwd)
 REQUIRE(l4dmm)
+REQUIRE_GLOBAL(srvdll)
+REQUIRE_GAMEDATA(vtidx_GameFrame) // note: for L4D1 only, always defined anyway
+REQUIRE_GAMEDATA(vtidx_GameShutdown)
+REQUIRE_GAMEDATA(vtidx_OnGameplayStart)
 
 static void **votecontroller;
 static int off_callerrecords = -1;
 static int off_voteissues;
 
+static void *director; // "TheDirector" server global
+
 // Note: the vote callers vector contains these as elements. We don't currently
 // do anything with the structure, but we're keeping it here for reference.
 /*struct CallerRecord {
@@ -74,7 +85,7 @@ static struct CVoteIssue *getissue(const char *textkey) {
 	}
 }
 
-static void reset(void) {
+static inline void reset(void) {
 	// reset the vote cooldowns if possible (will skip L4D1). only necessary on
 	// versions >2045 and on map 1, but it's easiest to do unconditionally
 	if (off_callerrecords != -1) {
@@ -84,16 +95,90 @@ static void reset(void) {
 				off_callerrecords);
 		recordvector->sz = 0;
 	}
-	struct CVoteIssue *issue = getissue("#L4D_vote_restart_game");
-	ExecuteCommand(issue);
+	ExecuteCommand(getissue("#L4D_vote_restart_game"));
 }
 
-static void change(const char *missionid) {
+static inline void change(const char *missionid) {
 	struct CVoteIssue *issue = getissue("#L4D_vote_mission_change");
 	SetIssueDetails(issue, missionid); // will just nop if invalid
 	ExecuteCommand(issue);
 }
 
+static short ffdelay = 0, ffamt;
+static bool mapchanging = false;
+
+HANDLE_EVENT(Tick, bool simulating) {
+	if (!mapchanging && ffdelay && !--ffdelay) fastfwd(ffamt, 30);
+}
+
+typedef void (*VCALLCONV OnGameplayStart_func)(void *this);
+static OnGameplayStart_func orig_OnGameplayStart;
+static void VCALLCONV hook_OnGameplayStart(void *this) {
+	orig_OnGameplayStart(this);
+	if (mapchanging) reset(); // prevent bots walking around. note ffdelay is 45
+	mapchanging = false; // resume countdown!
+}
+// Simply reuse the above for L4D1, since the calling ABI is the exact same!
+#define UnfreezeTeam_func OnGameplayStart_func
+#define UnfreezeTeam OnGameplayStart
+#define orig_UnfreezeTeam orig_OnGameplayStart
+#define hook_UnfreezeTeam hook_OnGameplayStart
+
+static inline int getffamt(const char *campaign) {
+	// TODO(compat): add popular custom campaigns too:
+	// - dark blood 2
+	// - grey scale
+	// - left 4 mario
+	// - ravenholm
+	// - warcelona
+	// - tour of terror
+	// - dam it
+	// - carried off
+	if (GAMETYPE_MATCHES(L4D1)) {
+		if (!strcmp(campaign, "Hospital")) return 9; // No Mercy
+		if (!strcmp(campaign, "SmallTown")) return 12; // Death Toll
+		if (!strcmp(campaign, "Airport")) return 12; // Dead Air
+		if (!strcmp(campaign, "Farm")) return 15; // Blood Harvest
+		if (!strcmp(campaign, "River")) return 15; // The Sacrifice
+		if (!strcmp(campaign, "Garage")) return 8; // Crash Course
+	}
+	else /* L4D2 */ {
+		if (!strncmp(campaign, "L4D2C", 5)) {
+			int ret;
+			switch (campaign[5]) {
+				case '1':
+					switch (campaign[6]) {
+						case '\0': return 13; // Dead Center
+						case '0': ret = 12; break; // Death Toll
+						case '1': ret = 13; break; // Dead Air
+						case '2': ret = 16; break; // Blood Harvest
+						case '3': ret = 18; break; // Cold Stream
+						case '4': ret = 16; break; // The Last Stand
+						default: return 0;
+					}
+					if (campaign[7]) return 0;
+					return ret;
+				case '2': ret = 12; break; // Dark Carnival
+				case '3': ret = 19; break; // Swamp Fever
+				case '4': ret = 8; break; // Hard Rain
+				case '5': ret = 13; break; // The Parish
+				case '6': ret = 10; break; // The Passing
+				case '7': ret = 15; break; // The Sacrifice
+				case '8': ret = 9; break; // No Mercy
+				case '9': ret = 8; break; // Crash Course
+				default: return 0;
+			}
+			if (campaign[6]) return 0;
+			return ret;
+		}
+	}
+	return 0; // if unknown, just don't skip, I guess.
+}
+
+DEF_CVAR_UNREG(sst_l4d_quickreset_fastfwd,
+		"Fast-forward through cutscenes when quick-resetting", 1,
+		CON_ARCHIVE | CON_HIDDEN)
+
 DEF_CCMD_HERE_UNREG(sst_l4d_quickreset,
 		"Reset (or switch) campaign and clear all vote cooldowns", 0) {
 	if (cmd->argc > 2) {
@@ -104,17 +189,29 @@ DEF_CCMD_HERE_UNREG(sst_l4d_quickreset,
 		con_warn("not hosting a server\n");
 		return;
 	}
-	if (cmd->argc == 2) {
-		const char *cur = l4dmm_curcampaign();
-		if (!cur || strcasecmp(cur, cmd->argv[1])) {
-			change(cmd->argv[1]);
-			return;
-		}
+	const char *campaign = l4dmm_curcampaign();
+	if (cmd->argc == 2 && (!campaign || strcasecmp(campaign, cmd->argv[1]))) {
+		change(cmd->argv[1]);
+		campaign = cmd->argv[1];
+		mapchanging = true;
+	}
+	else {
+		reset();
+		// same-map reset is delayed by about a second - save that time here
+		// also, set mapchanging back to false in case it got stuck somehow
+		if (!(mapchanging = !l4dmm_firstmap())) fastfwd(0.8, 10);
+	}
+	if (campaign && con_getvari(sst_l4d_quickreset_fastfwd) &&
+			(ffamt = getffamt(campaign))) {
+		ffdelay = 45; // 1.5s
 	}
-	reset();
 }
 
-PREINIT { return GAMETYPE_MATCHES(L4D); }
+PREINIT {
+	if (!GAMETYPE_MATCHES(L4D)) return false;
+	con_reg(sst_l4d_quickreset_fastfwd);
+	return true;
+}
 
 // Note: this returns a pointer to subsequent bytes for find_voteissues() below
 static inline const uchar *find_votecontroller(con_cmdcbv1 listissues_cb) {
@@ -191,6 +288,52 @@ static inline bool find_votecallers(void *votectrlspawn) {
 	return false;
 }
 
+#ifdef _WIN32
+static inline bool find_TheDirector(void *GameShutdown) {
+	// in 2045, literally the first instruction of this function is loading
+	// TheDirector into ECX. although, do the usual search in case moves a bit.
+	const uchar *insns = (const uchar *)GameShutdown;
+	for (const uchar *p = insns; p - insns < 24;) {
+		if (p[0] == X86_MOVRMW && p[1] == X86_MODRM(0, 1, 5)) {
+			void **indirect = mem_loadptr(p + 2);
+			director = *indirect;
+			return true;
+		}
+		NEXT_INSN(p, "load of TheDirector");
+	}
+	return false;
+}
+#endif
+
+static inline bool find_UnfreezeTeam(void *GameFrame) { // note: L4D1 only
+	// CServerGameDLL::GameFrame() loads TheDirector into ECX and then calls
+	// Director::Update()
+	const uchar *insns = (const uchar *)GameFrame, *p = insns;
+	while (p - insns < 192) {
+		if (p[0] == X86_MOVRMW && p[1] == X86_MODRM(0, 1, 5) &&
+				mem_loadptr(mem_loadptr(p + 2)) == director &&
+				p[6] == X86_CALL) {
+			p += 11 + mem_loadoffset(p + 7);
+			insns = p;
+			goto ok;
+		}
+		NEXT_INSN(p, "Director::Update call");
+	}
+	return false;
+ok: // Director::Update calls UnfreezeTeam after the first jmp instruction
+	while (p - insns < 96) {
+		// jz XXX; mov ecx, <reg>; call Director::UnfreezeTeam
+		if (p[0] == X86_JZ && p[2] == X86_MOVRMW && (p[3] & 0xF8) == 0xC8 &&
+				p[4] == X86_CALL) {
+			p += 9 + mem_loadoffset(p + 5);
+			orig_UnfreezeTeam = (UnfreezeTeam_func)p;
+			return true;
+		}
+		NEXT_INSN(p, "Director::UnfreezeTeam call");
+	}
+	return false;
+ }
+
 INIT {
 	struct con_cmd *cmd_listissues = con_findcmd("listissues");
 	if (!cmd_listissues) {
@@ -207,8 +350,41 @@ INIT {
 		errmsg_errorx("couldn't find vote issues list offset\n");
 		return false;
 	}
+	void **vtable;
+#ifdef _WIN32
+	void *GameShutdown = (*(void ***)srvdll)[vtidx_GameShutdown];
+	if (!find_TheDirector(GameShutdown)) {
+		errmsg_errorx("couldn't find TheDirector variable");
+		return false;
+	}
+#else
+#warning TODO(linux): should be able to just dlsym(server, "TheDirector")
+	return false;
+#endif
+#ifdef _WIN32 // L4D1 has no Linux build, no need to check whether L4D2
+	if (GAMETYPE_MATCHES(L4D2)) {
+#endif
+		vtable = mem_loadptr(director);
+		if (!os_mprot(vtable + vtidx_OnGameplayStart, sizeof(*vtable),
+				PAGE_READWRITE)) {
+			errmsg_errorsys("couldn't make virtual table writable");
+			return false;
+		}
+		orig_OnGameplayStart = (OnGameplayStart_func)hook_vtable(vtable,
+				vtidx_OnGameplayStart, (void *)&hook_OnGameplayStart);
+#ifdef _WIN32 // L4D1 has no Linux build!
+	}
+	else /* L4D1 */ {
+		void *GameFrame = (*(void ***)srvdll)[vtidx_GameFrame];
+		if (!find_UnfreezeTeam(GameFrame)) {
+			errmsg_errorx("couldn't find UnfreezeTeam function");
+			return false;
+		}
+		orig_UnfreezeTeam = (UnfreezeTeam_func)hook_inline(
+				(void *)orig_UnfreezeTeam, (void *)&hook_UnfreezeTeam);
+	}
+#endif
 	// Only try cooldown stuff for L4D2, since L4D1 always had unlimited votes.
-	// NOTE: assuming L4D2 always has Spawn in gamedata (why wouldn't it?)
 	if (GAMETYPE_MATCHES(L4D2)) {
 		// g_voteController is invalid if not running a server so get the
 		// vtable by inspecting the ent factory code instead
@@ -217,7 +393,7 @@ INIT {
 			errmsg_errorx("couldn't find vote controller entity factory");
 			goto nocd;
 		}
-		void **vtable = ent_findvtable(factory, "CVoteController");
+		vtable = ent_findvtable(factory, "CVoteController");
 		if (!vtable) {
 			errmsg_errorx("couldn't find CVoteController vtable");
 			goto nocd;
@@ -228,7 +404,18 @@ nocd:		errmsg_note("resetting a first map will not clear vote cooldowns");
 		}
 	}
 	con_reg(sst_l4d_quickreset);
+	sst_l4d_quickreset_fastfwd->base.flags &= ~CON_HIDDEN;
 	return true;
 }
 
+END {
+	if (GAMETYPE_MATCHES(L4D2)) {
+		unhook_vtable(mem_loadptr(director), vtidx_OnGameplayStart,
+				(void *)orig_OnGameplayStart);
+	}
+	else {
+		unhook_inline((void *)orig_UnfreezeTeam);
+	}
+}
+
 // vi: sw=4 ts=4 noet tw=80 cc=80