From 18b719de8043103c15fcb82bd5396092812bd00b Mon Sep 17 00:00:00 2001
From: ceriel <none@none>
Date: Fri, 2 Dec 1988 15:39:59 +0000
Subject: [PATCH] killbss routine smarter now; does not overwrite all BSS; did
 not work as it should, because systemcall interface also uses the fact that
 BSS = 0

---
 lang/m2/libm2/XXTermcap.c | 35 ++++++++++++++++++++++-------------
 lang/m2/libm2/halt.c      |  2 +-
 lang/m2/libm2/init.c      | 26 +++++++++++++++++++++++---
 lang/m2/libm2/stackprio.c |  2 +-
 4 files changed, 47 insertions(+), 18 deletions(-)

diff --git a/lang/m2/libm2/XXTermcap.c b/lang/m2/libm2/XXTermcap.c
index be7e4bdf0..46ff28c41 100644
--- a/lang/m2/libm2/XXTermcap.c
+++ b/lang/m2/libm2/XXTermcap.c
@@ -19,12 +19,12 @@
 #define ISSPACE(c)	((c) == ' ' || (c) == '\t' || (c) == '\r' || (c) == '\n')
 #define ISDIGIT(x)	((x) >= '0' && (x) <= '9')
 
-short	ospeed;		/* output speed */
-char	PC;		/* padding character */
-char	*BC;		/* back cursor movement */
-char	*UP;		/* up cursor movement */
+short	ospeed = 0;		/* output speed */
+char	PC = 0;			/* padding character */
+char	*BC = 0;		/* back cursor movement */
+char	*UP = 0;		/* up cursor movement */
 
-static char	*capab;		/* the capability itself */
+static char	*capab = 0;		/* the capability itself */
 static int	check_for_tc();
 static int	match_name();
 
@@ -181,8 +181,10 @@ char	*name;
 		else file = "/etc/termcap";
 	} else
 		file = "/etc/termcap";
-	if ((fp = open(file, 0)) < 0)
+	if ((fp = open(file, 0)) < 0) {
+		capab = 0;
 		return(-1); 
+	}
 	while (fgets(buf, 1024, fp) != NULL) {
 		if (buf[0] == '#') continue;
 		while (*(cp = &buf[strlen(buf) - 2]) == '\\')
@@ -191,9 +193,14 @@ char	*name;
 		if (match_name(buf, name)) {
 			strcpy(bp, buf);
 			close(fp);
-			return(check_for_tc());
+			if(check_for_tc() == 0) {
+				capab = 0;
+				return 0;
+			}
+			return 1;
 		}
 	}
+	capab = 0;
 	close(fp);
 	return(0);
 }
@@ -236,7 +243,9 @@ check_for_tc()
 			return(0);	/* no : in termcap entry */
 	if (p[1] != 't' || p[2] != 'c')
 		return(1);
-	if (count > 16) return(0);	/* recursion in tc= definitions */
+	if (count > 16) {
+		return(0);	/* recursion in tc= definitions */
+	}
 	count++;
 	strcpy(terminalname, &p[4]);
 	q = terminalname;
@@ -264,9 +273,9 @@ char	*id;
 	char	*cp;
 	int	ret;
 
-	if ((cp = capab) == NULL || id == NULL)
+	if ((cp = capab) == NULL || id == NULL || *cp == 0)
 		return(-1);
-	while (*++cp != ':')
+	while (*++cp && *cp != ':')
 		;
 	while (*cp) {
 		cp++;
@@ -298,9 +307,9 @@ char	*id;
 {
 	char	*cp;
 
-	if ((cp = capab) == NULL || id == NULL)
+	if ((cp = capab) == NULL || id == NULL || *cp == 0)
 		return(-1);
-	while (*++cp != ':')
+	while (*++cp && *cp != ':')
 		;
 	while (*cp) {
 		cp++;
@@ -328,7 +337,7 @@ char	**area;
 	char	*ret;
 	int	i;
 
-	if ((cp = capab) == NULL || id == NULL)
+	if ((cp = capab) == NULL || id == NULL || *cp == 0)
 		return(NULL);
 	while (*++cp != ':')
 		;
diff --git a/lang/m2/libm2/halt.c b/lang/m2/libm2/halt.c
index e32e8900f..01eeef3f2 100644
--- a/lang/m2/libm2/halt.c
+++ b/lang/m2/libm2/halt.c
@@ -10,7 +10,7 @@
 */
 #define MAXPROCS 16
 
-static int callindex;
+static int callindex = 0;
 static int (*proclist[MAXPROCS])();
 
 _cleanup()
diff --git a/lang/m2/libm2/init.c b/lang/m2/libm2/init.c
index 37b3231b5..be9069027 100644
--- a/lang/m2/libm2/init.c
+++ b/lang/m2/libm2/init.c
@@ -31,10 +31,30 @@ init()
 	sigtrp(M2_UNIXSIG, SIGALRM);
 	sigtrp(M2_UNIXSIG, SIGTERM);
 }
+#if em22 || em24 || em44
+killbss()
+{
+}
+#else
+
+static int blablabla;		/*	We cannot use end, because then also
+					bss allocated for the systemcall lib
+					would be overwritten. Lets hope that
+					this helps ...
+				*/
+
+killbss()
+{
+	extern char *edata;
+	register char *p = (char *) &edata;
+
+	while (p < (char *) &blablabla) *p++ = 0x66;
+}
+#endif
 
 extern int catch();
 
 int (*handler)() = catch;
-char **argv, **environ;
-int argc, StackSize;
-char *CurrentProcess, MainProcess, StackBase, MainLB;
+char **argv = 0, **environ = 0;
+int argc = 0, StackSize = 0;
+char *CurrentProcess = 0, MainProcess = 0, StackBase = 0, MainLB = 0;
diff --git a/lang/m2/libm2/stackprio.c b/lang/m2/libm2/stackprio.c
index a32044062..ecd3fee2a 100644
--- a/lang/m2/libm2/stackprio.c
+++ b/lang/m2/libm2/stackprio.c
@@ -9,7 +9,7 @@
   Version:	$Header$
 */
 
-static unsigned prio;
+static unsigned prio = 0;
 
 stackprio(n)
 	unsigned n;
-- 
2.34.1