early directory validation

Allow early prefix directory validation to help prevent
failed games and lost save files due to incorrect config
file settings.

doc/fixes34.1

@@ -168,3 +168,4 @@ travel option
 mouse_support wincap option
 debug mode: #panic routine to test panic() and panic save file generation
 a new PANICLOG optional file to log the reason for panic and impossible messages
+added validate_prefix_locations() for early directory prefix validation

include/extern.h

@@ -639,6 +639,7 @@ E void FDECL(check_recordfile, (const char *));
 E void NDECL(read_wizkit);
 #endif
 E void FDECL(paniclog, (const char *, const char *));
+E int FDECL(validate_prefix_locations, (char *));
 
 /* ### fountain.c ### */
 

src/files.c

@@ -153,6 +153,42 @@ int whichprefix, buffnum;
 #endif
 }
 
+/* reasonbuf must be at least BUFSZ, supplied by caller */
+int
+validate_prefix_locations(reasonbuf)
+char *reasonbuf;
+{
+#if defined(NOCWD_ASSUMPTIONS)
+	FILE *fp;
+	const char *filename;
+	int prefcnt, failcount = 0;
+	char failbuf[BUFSZ];
+	
+	failbuf[0] = '\0';
+	if (reasonbuf) reasonbuf[0] = '\0';
+	for (prefcnt = 1; prefcnt < PREFIX_COUNT; prefcnt++) {
+		filename = fqname("validate", prefcnt, 3);
+		if ((fp = fopen(filename, "w"))) {
+			fclose(fp);
+			(void) unlink(filename);
+		} else {
+			if (failcount) {
+				Strcat(failbuf,", ");
+				if (reasonbuf) Strcat(reasonbuf,", ");
+			}
+			/* the paniclog entry gets the value of errno */
+			Sprintf(eos(failbuf), "%s:%d", fqn_prefix_names[prefcnt], errno);
+			if (reasonbuf) Strcat(reasonbuf, fqn_prefix_names[prefcnt]);
+			failcount++;
+		}	
+	}
+	if (failcount) {
+		paniclog("Invalid locations", failbuf);
+		return 0;
+	}
+#endif
+	return 1;
+}
 
 /* fopen a file, with OS-dependent bells and whistles */
 /* NOTE: a simpler version of this routine also exists in util/dlb_main.c */
@@ -1289,7 +1325,7 @@ char		*tmp_levels;
 	} else if (match_varname(buf, "LEVELDIR", 4) ||
 		   match_varname(buf, "LEVELS", 4)) {
 		adjust_prefix(bufp, LEVELPREFIX);
-	} else if (match_varname(buf, "SAVE", 4)) {
+	} else if (match_varname(buf, "SAVEDIR", 4)) {
 		adjust_prefix(bufp, SAVEPREFIX);
 	} else if (match_varname(buf, "BONESDIR", 5)) {
 		adjust_prefix(bufp, BONESPREFIX);

sys/share/pcmain.c

@@ -105,6 +105,9 @@ char *argv[];
 
 	register int fd;
 	register char *dir;
+#ifdef NOCWD_ASSUMPTIONS
+	char failbuf[BUFSZ];
+#endif
 
 #if defined(__BORLANDC__) && !defined(_WIN32)
 	startup();
@@ -171,6 +174,14 @@ char *argv[];
 #endif
 	initoptions();
 
+#ifdef NOCWD_ASSUMPTIONS
+	if (!validate_prefix_locations(failbuf)) {
+		raw_printf("Some invalid directory locations were specified:\n\t%s\n",
+				failbuf);
+		 nethack_exit(EXIT_FAILURE);
+	}
+#endif
+
 #if defined(TOS) && defined(TEXTCOLOR)
 	if (iflags.BIOS && iflags.use_color)
 		set_colors();

sys/share/pcunix.c

@@ -186,7 +186,7 @@ gotlock:
 		chdirx(orgdir, 0);
 #if defined(WIN32)
 		error("cannot creat file (%s.)\n%s\n%s\"%s\" exists?\n", 
-				fq_lock, strerror(ern), "Are you sure that the directory",
+				fq_lock, strerror(ern), " Are you sure that the directory",
 				fqn_prefix[LEVELPREFIX]);
 #else
 		error("cannot creat file (%s.)", fq_lock);