level file handling and trickery feedback

1) consolidate all core usage of `errno' in files.c;
2) give more feedback for any failure by create_levelfile or open_levelfile,
   similar to what was being done for problems during level change;
3) include trickery info in paniclog (many instances of "trickery" seem to
   be due to disk or quota problems rather than user misbehavior...).

The create_levelfile call in pcmain probably ought to be changed to use
error feedback, but in the meantime this should continue working.

Perhaps error() should be modified to update paniclog too, but I didn't
want to go through all its port-specific incarnations making changes.

include/extern.h

@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)extern.h	3.4	2002/03/29	*/
+/*	SCCS Id: @(#)extern.h	3.4	2002/08/22	*/
 /* Copyright (c) Steve Creps, 1988.				  */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -605,8 +605,8 @@ E void FDECL(store_version, (int));
 E void NDECL(set_lock_and_bones);
 #endif
 E void FDECL(set_levelfile_name, (char *,int));
-E int FDECL(create_levelfile, (int));
+E int FDECL(create_levelfile, (int,char *));
-E int FDECL(open_levelfile, (int));
+E int FDECL(open_levelfile, (int,char *));
 E void FDECL(delete_levelfile, (int));
 E void NDECL(clearlocks);
 E int FDECL(create_bonesfile, (d_level*,char **));
@@ -1643,7 +1643,7 @@ E NhRegion* FDECL(create_gas_cloud, (XCHAR_P, XCHAR_P, int, int));
 
 E void FDECL(inven_inuse, (BOOLEAN_P));
 E int FDECL(dorecover, (int));
-E void NDECL(trickery);
+E void FDECL(trickery, (char *));
 E void FDECL(getlev, (int,int,XCHAR_P,BOOLEAN_P));
 E void NDECL(minit);
 E boolean FDECL(lookup_id_mapping, (unsigned, unsigned *));

src/do.c

@@ -7,19 +7,6 @@
 #include "hack.h"
 #include "lev.h"
 
-#include <errno.h>
-#ifdef _MSC_VER	/* MSC 6.0 defines errno quite differently */
-# if (_MSC_VER >= 600)
-#  define SKIP_ERRNO
-# endif
-#endif
-#ifndef SKIP_ERRNO
-#ifdef _DCC
-const
-#endif
-extern int errno;
-#endif
-
 #ifdef SINKS
 # ifdef OVLB
 STATIC_DCL void FDECL(trycall, (struct obj *));
@@ -838,14 +825,14 @@ STATIC_OVL int
 currentlevel_rewrite()
 {
 	register int fd;
+	char whynot[BUFSZ];
 
 	/* since level change might be a bit slow, flush any buffered screen
 	 *  output (like "you fall through a trap door") */
 	mark_synch();
 
-	fd = create_levelfile(ledger_no(&u.uz));
+	fd = create_levelfile(ledger_no(&u.uz), whynot);
-
+	if (fd < 0) {
-	if(fd < 0) {
 		/*
 		 * This is not quite impossible: e.g., we may have
 		 * exceeded our quota. If that is the case then we
@@ -853,8 +840,7 @@ currentlevel_rewrite()
 		 * Another possibility is that the directory was not
 		 * writable.
 		 */
-		pline("Cannot create level file for level %d.",
+		pline("%s", whynot);
-						ledger_no(&u.uz));
 		return -1;
 	}
 
@@ -914,6 +900,7 @@ boolean at_stairs, falling, portal;
 		familiar = FALSE;
 	boolean new = FALSE;	/* made a new level? */
 	struct monst *mtmp;
+	char whynot[BUFSZ];
 
 	if (dunlev(newlevel) > dunlevs_in_dungeon(newlevel))
 		newlevel->dlevel = dunlevs_in_dungeon(newlevel);
@@ -1049,11 +1036,11 @@ boolean at_stairs, falling, portal;
 		new = TRUE;	/* made the level */
 	} else {
 		/* returning to previously visited level; reload it */
-		fd = open_levelfile(new_ledger);
+		fd = open_levelfile(new_ledger, whynot);
 		if (fd < 0) {
-			pline("Cannot open file (#%d) for level %d (errno %d).",
+			pline("%s", whynot);
-					(int) new_ledger, depth(&u.uz), errno);
 			pline("Probably someone removed it.");
+			killer = whynot;
 			done(TRICKED);
 			/* we'll reach here if running in wizard mode */
 			error("Cannot continue this game.");

src/end.c

@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)end.c	3.4	2001/09/24	*/
+/*	SCCS Id: @(#)end.c	3.4	2002/08/22	*/
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -549,6 +549,19 @@ int how;
 	struct obj *corpse = (struct obj *)0;
 	long umoney;
 
+	if (how == TRICKED) {
+	    if (killer) {
+		paniclog("trickery", killer);
+		killer = 0;
+	    }
+#ifdef WIZARD
+	    if (wizard) {
+		You("are a very tricky wizard, it seems.");
+		return;
+	    }
+#endif
+	}
+
 	/* kilbuf: used to copy killer in case it comes from something like
 	 *	xname(), which would otherwise get overwritten when we call
 	 *	xname() when listing possessions
@@ -561,12 +574,7 @@ int how;
 		killer_format = KILLED_BY;
 	Strcpy(kilbuf, (!killer || how >= PANICKED ? deaths[how] : killer));
 	killer = kilbuf;
-#ifdef WIZARD
+
-	if (wizard && how == TRICKED) {
-		You("are a very tricky wizard, it seems.");
-		return;
-	}
-#endif
 	if (how < PANICKED) u.umortality++;
 	if (Lifesaved && (how <= GENOCIDED)) {
 		pline("But wait...");

src/files.c

@@ -15,8 +15,17 @@
 #include <fcntl.h>
 #endif
 
-#if defined(NOCWD_ASSUMPTIONS)
 #include <errno.h>
+#ifdef _MSC_VER	/* MSC 6.0 defines errno quite differently */
+# if (_MSC_VER >= 600)
+#  define SKIP_ERRNO
+# endif
+#endif
+#ifndef SKIP_ERRNO
+# ifdef _DCC
+const
+# endif
+extern int errno;
 #endif
 
 #if defined(UNIX) && defined(QT_GRAPHICS)
@@ -24,10 +33,6 @@
 #endif
 
 #if defined(UNIX) || defined(VMS)
-#include <errno.h>
-# ifndef SKIP_ERRNO
-extern int errno;
-# endif
 #include <signal.h>
 #endif
 
@@ -404,12 +409,14 @@ int lev;
 }
 
 int
-create_levelfile(lev)
+create_levelfile(lev, errbuf)
 int lev;
+char errbuf[];
 {
 	int fd;
 	const char *fq_lock;
 
+	if (errbuf) *errbuf = '\0';
 	set_levelfile_name(lock, lev);
 	fq_lock = fqname(lock, LEVELPREFIX, 0);
 
@@ -434,18 +441,24 @@ int lev;
 
 	if (fd >= 0)
 	    level_info[lev].flags |= LFILE_EXISTS;
+	else if (errbuf)	/* failure explanation */
+	    Sprintf(errbuf,
+		    "Cannot create file \"%s\" for level %d (errno %d).",
+		    lock, lev, errno);
 
 	return fd;
 }
 
 
 int
-open_levelfile(lev)
+open_levelfile(lev, errbuf)
 int lev;
+char errbuf[];
 {
 	int fd;
 	const char *fq_lock;
 
+	if (errbuf) *errbuf = '\0';
 	set_levelfile_name(lock, lev);
 	fq_lock = fqname(lock, LEVELPREFIX, 0);
 #ifdef MFLOPPY
@@ -463,6 +476,15 @@ int lev;
 # endif
 	fd = open(fq_lock, O_RDONLY | O_BINARY, 0);
 #endif
+
+	/* for failure, return an explanation that our caller can use;
+	   settle for `lock' instead of `fq_lock' because the latter
+	   might end up being too big for nethack's BUFSZ */
+	if (fd < 0 && errbuf)
+	    Sprintf(errbuf,
+		    "Cannot open file \"%s\" for level %d (errno %d).",
+		    lock, lev, errno);
+
 	return fd;
 }
 
@@ -553,7 +575,7 @@ int fd;
 {
  	if (lftrack.fd == fd) {
 		really_close();	/* close it, but reopen it to hold it */
-		fd = open_levelfile(0);
+		fd = open_levelfile(0, (char *)0);
 		lftrack.nethack_thinks_it_is_open = FALSE;
 		return 0;
 	}
@@ -2180,7 +2202,7 @@ recover_savefile()
 	xchar levc;
 	struct version_info version_data;
 	int processed[256];
-	char savename[SAVESIZE];
+	char savename[SAVESIZE], errbuf[BUFSZ];
 
 	for (lev = 0; lev < 256; lev++)
 		processed[lev] = 0;
@@ -2191,9 +2213,9 @@ recover_savefile()
 	 *	name of save file nethack would have created
 	 *	and game state
 	 */
-	gfd = open_levelfile(0);
+	gfd = open_levelfile(0, errbuf);
 	if (gfd < 0) {
-	    raw_printf("Cannot open level 0 for %s.\n", lock);
+	    raw_printf("%s\n", errbuf);
 	    return FALSE;
 	}
 	if (read(gfd, (genericptr_t) &hpid, sizeof hpid) != sizeof hpid) {
@@ -2232,9 +2254,9 @@ recover_savefile()
 	    return FALSE;
 	}
 
-	lfd = open_levelfile(savelev);
+	lfd = open_levelfile(savelev, errbuf);
 	if (lfd < 0) {
-	    raw_printf("\nCannot open level of save for %s.\n", lock);
+	    raw_printf("\n%s\n", errbuf);
 	    (void)close(gfd);
 	    (void)close(sfd);
 	    delete_savefile();
@@ -2273,7 +2295,7 @@ recover_savefile()
 		 * maximum level number (for the endlevel) must be < 256
 		 */
 		if (lev != savelev) {
-			lfd = open_levelfile(lev);
+			lfd = open_levelfile(lev, (char *)0);
 			if (lfd >= 0) {
 				/* any or all of these may not exist */
 				levc = (xchar) lev;

src/restore.c

@@ -484,10 +484,14 @@ xchar ltmp;
 #endif
 {
 	register int nfd;
+	char whynot[BUFSZ];
 
-	nfd = create_levelfile(ltmp);
+	nfd = create_levelfile(ltmp, whynot);
-
+	if (nfd < 0) {
-	if (nfd < 0)	panic("Cannot open temp level %d!", ltmp);
+		/* BUG: should suppress any attempt to write a panic
+		   save file if file creation is now failing... */
+		panic("restlevelfile: %s", whynot);
+	}
 #ifdef MFLOPPY
 	if (!savelev(nfd, ltmp, COUNT_SAVE)) {
 
@@ -675,11 +679,13 @@ register int fd;
 }
 
 void
-trickery()
+trickery(reason)
+char *reason;
 {
 	pline("Strange, this map is not as I remember it.");
 	pline("Somebody is trying some trickery here...");
 	pline("This game is void.");
+	killer = reason;
 	done(TRICKED);
 }
 
@@ -719,16 +725,18 @@ boolean ghostly;
 #else
 	mread(fd, (genericptr_t) &dlvl, sizeof(dlvl));
 #endif
-	if((pid && pid != hpid) || (lev && dlvl != lev)) {
+	if ((pid && pid != hpid) || (lev && dlvl != lev)) {
+	    char trickbuf[BUFSZ];
+
+	    if (pid && pid != hpid)
+		Sprintf(trickbuf, "PID (%d) doesn't match saved PID (%d)!",
+			hpid, pid);
+	    else
+		Sprintf(trickbuf, "This is level %d, not %d!", dlvl, lev);
 #ifdef WIZARD
-		if (wizard) {
+	    if (wizard) pline(trickbuf);
-			if (pid && pid != hpid)
-				pline("PID (%d) doesn't match saved PID (%d)!", hpid, pid);
-			else if (lev && dlvl != lev)
-				pline("This is level %d, not %d!", dlvl, lev);
-		}
 #endif
-		trickery();
+	    trickery(trickbuf);
 	}
 
 #ifdef RLECOMP

src/save.c

@@ -1,9 +1,10 @@
-/*	SCCS Id: @(#)save.c	3.4	2002/01/19	*/
+/*	SCCS Id: @(#)save.c	3.4	2002/08/22	*/
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
 #include "hack.h"
 #include "lev.h"
+#include "quest.h"
 
 #ifndef NO_SIGNAL
 #include <signal.h>
@@ -12,8 +13,6 @@
 #include <fcntl.h>
 #endif
 
-#include "quest.h"
-
 #ifdef MFLOPPY
 long bytes_counted;
 static int count_only;
@@ -117,6 +116,7 @@ dosave0()
 	register int fd, ofd;
 	xchar ltmp;
 	d_level uz_save;
+	char whynot[BUFSZ];
 
 	if (!SAVEF[0])
 		return 0;
@@ -150,7 +150,6 @@ dosave0()
 	HUP mark_synch();	/* flush any buffered screen output */
 
 	fd = create_savefile();
-
 	if(fd < 0) {
 		HUP pline("Cannot open save file.");
 		(void) delete_savefile();	/* ab@unido */
@@ -243,11 +242,12 @@ dosave0()
 		}
 		mark_synch();
 #endif
-		ofd = open_levelfile(ltmp);
+		ofd = open_levelfile(ltmp, whynot);
 		if (ofd < 0) {
-		    HUP pline("Cannot read level %d.", ltmp);
+		    HUP pline("%s", whynot);
 		    (void) close(fd);
 		    (void) delete_savefile();
+		    HUP killer = whynot;
 		    HUP done(TRICKED);
 		    return(0);
 		}
@@ -328,6 +328,7 @@ savestateinlock()
 {
 	int fd, hpid;
 	static boolean havestate = TRUE;
+	char whynot[BUFSZ];
 
 	/* When checkpointing is on, the full state needs to be written
 	 * on each checkpoint.  When checkpointing is off, only the pid
@@ -347,24 +348,30 @@ savestateinlock()
 		 * to any internal compression schemes since they must be
 		 * readable by an external utility
 		 */
-		fd = open_levelfile(0);
+		fd = open_levelfile(0, whynot);
 		if (fd < 0) {
-		    pline("Cannot open level 0.");
+		    pline("%s", whynot);
 		    pline("Probably someone removed it.");
+		    killer = whynot;
 		    done(TRICKED);
 		    return;
 		}
 
 		(void) read(fd, (genericptr_t) &hpid, sizeof(hpid));
 		if (hackpid != hpid) {
-		    pline("Level 0 pid bad!");
+		    Sprintf(whynot,
+			    "Level #0 pid (%d) doesn't match ours (%d)!",
+			    hpid, hackpid);
+		    pline("%s", whynot);
+		    killer = whynot;
 		    done(TRICKED);
 		}
 		(void) close(fd);
 
-		fd = create_levelfile(0);
+		fd = create_levelfile(0, whynot);
 		if (fd < 0) {
-		    pline("Cannot rewrite level 0.");
+		    pline("%s", whynot);
+		    killer = whynot;
 		    done(TRICKED);
 		    return;
 		}

sys/share/pcmain.c

@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)pcmain.c	3.4	1997/01/22	*/
+/*	SCCS Id: @(#)pcmain.c	3.4	2002/08/22	*/
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -338,7 +338,7 @@ char *argv[];
 
 	/* Set up level 0 file to keep the game state.
 	 */
-	fd = create_levelfile(0);
+	fd = create_levelfile(0, (char *)0);
 	if (fd < 0) {
 		raw_print("Cannot create lock file");
 	} else {