Remove STRSPACE limitations.

A bit wasteful, but not too intrusive.

Also remove pushback buffer limitations, as this would be mostly useless
otherwise.

Incidentally, pushback buffer overflow detection in pbstr was wrong.

4 files changed, 125 insertions, 48 deletions

diff --git a/usr.bin/m4/extern.h b/usr.bin/m4/extern.h
index 0ffc9de3339..94908ff34f7 100644
--- a/usr.bin/m4/extern.h
+++ b/usr.bin/m4/extern.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: extern.h,v 1.7 1999/09/06 13:20:40 espie Exp $	*/
+/*	$OpenBSD: extern.h,v 1.8 1999/09/06 13:29:32 espie Exp $	*/
 /*	$NetBSD: extern.h,v 1.3 1996/01/13 23:25:24 pk Exp $	*/
 
 /*-
@@ -70,6 +70,8 @@ void	pbstr __P((char *));
 void	putback __P((int));
 void	remhash __P((char *, int));
 void	usage __P((void));
+void initspaces __P((void));
+char *compute_prevep __P((void));
 
 extern ndptr hashtab[];		/* hash table for macros etc. */
 extern stae mstack[];		/* stack of m4 machine */
@@ -81,12 +83,10 @@ extern int ilevel;		/* input file stack pointer */
 extern int oindex;		/* diversion index. */
 extern int sp;			/* current m4 stack pointer */
 extern pbent *bp;		/* first available character */
-extern pbent buf[];		/* push-back buffer */
+extern pbent *buf;		/* push-back buffer */
 extern pbent *bufbase;		/* buffer base for this ilevel */
 extern pbent *bbase[];		/* buffer base per ilevel */
 extern char ecommt[];		/* end character for comment */
-extern char *endest;		/* end of string space */
-extern pbent *endpbb;		/* end of push-back buffer */
 extern char *ep;		/* first free char in strspace */
 extern char lquote[];		/* left quote character (`) */
 extern char *m4wraps;		/* m4wrap string default. */
diff --git a/usr.bin/m4/main.c b/usr.bin/m4/main.c
index 1e7be8c578d..a2a6b39d3df 100644
--- a/usr.bin/m4/main.c
+++ b/usr.bin/m4/main.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: main.c,v 1.13 1999/09/06 13:24:59 espie Exp $	*/
+/*	$OpenBSD: main.c,v 1.14 1999/09/06 13:29:32 espie Exp $	*/
 /*	$NetBSD: main.c,v 1.12 1997/02/08 23:54:49 cgd Exp $	*/
 
 /*-
@@ -47,7 +47,7 @@ static char copyright[] =
 #if 0
 static char sccsid[] = "@(#)main.c	8.1 (Berkeley) 6/6/93";
 #else
-static char rcsid[] = "$OpenBSD: main.c,v 1.13 1999/09/06 13:24:59 espie Exp $";
+static char rcsid[] = "$OpenBSD: main.c,v 1.14 1999/09/06 13:29:32 espie Exp $";
 #endif
 #endif /* not lint */
 
@@ -72,15 +72,7 @@ static char rcsid[] = "$OpenBSD: main.c,v 1.13 1999/09/06 13:24:59 espie Exp $";
 #include "pathnames.h"
 
 ndptr hashtab[HASHSIZE];	/* hash table for macros etc.  */
-pbent buf[BUFSIZE];		/* push-back buffer	       */
-pbent *bufbase = buf;		/* the base for current ilevel */
-pbent *bbase[MAXINP];		/* the base for each ilevel    */
-pbent *bp = buf; 		/* first available character   */
-pbent *endpbb = buf+BUFSIZE;	/* end of push-back buffer     */
 stae mstack[STACKMAX+1]; 	/* stack of m4 machine         */
-char strspace[STRSPMAX+1];	/* string space for evaluation */
-char *ep = strspace;		/* first free char in strspace */
-char *endest= strspace+STRSPMAX;/* end of string space	       */
 int sp; 			/* current m4  stack pointer   */
 int fp; 			/* m4 call frame pointer       */
 FILE *infile[MAXINP];		/* input file stack (0=stdin)  */
@@ -164,6 +156,7 @@ main(argc,argv)
 		signal(SIGINT, onintr);
 
 	initkwds();
+	initspaces();
 
 	while ((c = getopt(argc, argv, "tD:U:o:")) != -1)
 		switch(c) {
diff --git a/usr.bin/m4/mdef.h b/usr.bin/m4/mdef.h
index f4498c057ba..ed5baaa61c2 100644
--- a/usr.bin/m4/mdef.h
+++ b/usr.bin/m4/mdef.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mdef.h,v 1.5 1999/09/06 13:10:48 espie Exp $	*/
+/*	$OpenBSD: mdef.h,v 1.6 1999/09/06 13:29:32 espie Exp $	*/
 /*	$NetBSD: mdef.h,v 1.7 1996/01/13 23:25:27 pk Exp $	*/
 
 /*
@@ -97,15 +97,15 @@
  */
 
 #define EOS             '\0'
-#define MAXINP          10              /* maximum include files   */
-#define MAXOUT          10              /* maximum # of diversions */
-#define MAXSTR          512             /* maximum size of string  */
-#define BUFSIZE         4096            /* size of pushback buffer */
-#define STACKMAX        1024            /* size of call stack      */
-#define STRSPMAX        4096            /* size of string space    */
-#define MAXTOK          MAXSTR          /* maximum chars in a tokn */
-#define HASHSIZE        199             /* maximum size of hashtab */
-#define MAXCCHARS	5		/* max size of comment/quote delim */
+#define MAXINP          10              /* maximum include files   	    */
+#define MAXOUT          10              /* maximum # of diversions 	    */
+#define MAXSTR          512             /* maximum size of string  	    */
+#define BUFSIZE         4096            /* starting size of pushback buffer */
+#define STACKMAX        1024            /* size of call stack      	    */
+#define STRSPMAX        4096            /* starting size of string space    */
+#define MAXTOK          MAXSTR          /* maximum chars in a tokn 	    */
+#define HASHSIZE        199             /* maximum size of hashtab 	    */
+#define MAXCCHARS	5		/* max size of comment/quote delim  */
  
 #define ALL             1
 #define TOP             0
@@ -177,6 +177,6 @@ typedef short pbent;		/* pushback entry; needs to hold chars + EOF */
  */
 #define PARLEV  (mstack[fp].sfra)
 #define CALTYP  (mstack[fp-1].sfra)
-#define PREVEP	(mstack[fp+3].sstr)
+#define PREVEP	compute_prevep() 
 #define PREVSP	(fp-3)
 #define PREVFP	(mstack[fp-2].sfra)
diff --git a/usr.bin/m4/misc.c b/usr.bin/m4/misc.c
index 84d923b5d3e..07e15a89f07 100644
--- a/usr.bin/m4/misc.c
+++ b/usr.bin/m4/misc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: misc.c,v 1.8 1999/09/06 13:20:40 espie Exp $	*/
+/*	$OpenBSD: misc.c,v 1.9 1999/09/06 13:29:32 espie Exp $	*/
 /*	$NetBSD: misc.c,v 1.6 1995/09/28 05:37:41 tls Exp $	*/
 
 /*
@@ -41,7 +41,7 @@
 #if 0
 static char sccsid[] = "@(#)misc.c	8.1 (Berkeley) 6/6/93";
 #else
-static char rcsid[] = "$OpenBSD: misc.c,v 1.8 1999/09/06 13:20:40 espie Exp $";
+static char rcsid[] = "$OpenBSD: misc.c,v 1.9 1999/09/06 13:29:32 espie Exp $";
 #endif
 #endif /* not lint */
 
@@ -58,6 +58,23 @@ static char rcsid[] = "$OpenBSD: misc.c,v 1.8 1999/09/06 13:20:40 espie Exp $";
 #include "extern.h"
 #include "pathnames.h"
 
+
+char *ep;		/* first free char in strspace */
+static char *strspace;	/* string space for evaluation */
+static char *endest;	/* end of string space	       */
+static size_t strsize = STRSPMAX;
+static size_t bufsize = BUFSIZE;
+static int low_sp = 0;
+
+pbent *buf;			/* push-back buffer	       */
+pbent *bufbase;			/* the base for current ilevel */
+pbent *bbase[MAXINP];		/* the base for each ilevel    */
+pbent *bp; 			/* first available character   */
+static pbent *endpbb;			/* end of push-back buffer     */
+
+
+static void enlarge_bufspace();
+static void enlarge_strspace();
 /*
  * find the index of second str in the first str.
  */
@@ -81,10 +98,9 @@ void
 putback(c)
 pbent c;
 {
-	if (bp < endpbb)
-		*bp++ = c;
-	else
-		errx(1, "too many characters pushed back");
+	if (bp >= endpbb)
+		enlarge_bufspace();
+	*bp++ = c;
 }
 
 /*
@@ -96,20 +112,13 @@ void
 pbstr(s)
 register char *s;
 {
-	register char *es;
-	pbent *zp;
-
-	es = s;
-	zp = bp;
-
-	while (*es)
-		es++;
-	es--;
-	while (es >= s)
-		if (zp < endpbb)
-			*zp++ = *es--;
-	if ((bp = zp) == endpbb)
-		errx(1, "too many characters pushed back");
+	size_t n;
+
+	n = strlen(s);
+	while (endpbb - bp < n)
+		enlarge_bufspace();
+	while (n > 0)
+		*bp++ = s[--n];
 }
 
 /*
@@ -131,6 +140,66 @@ int n;
 		putback('-');
 }
 
+
+void 
+initspaces()
+{
+	int i;
+
+	strspace = xalloc(strsize+1);
+	ep = strspace;
+	endest = strspace+strsize;
+	buf = (pbent *)xalloc(bufsize * sizeof(pbent));
+	bufbase = buf;
+	bp = buf;
+	endpbb = buf + bufsize;
+	for (i = 0; i < MAXINP; i++)
+		bbase[i] = buf;
+}
+
+/* XXX when chrsave is called, the current argument is
+ * always topmost on the stack.  We make use of this to
+ * duplicate it transparently, and to reclaim the correct
+ * space when the stack is unwound.
+ */
+static
+void enlarge_strspace()
+{
+	char *newstrspace;
+
+	low_sp = sp;
+	strsize *= 2;
+	newstrspace = malloc(strsize + 1);
+	if (!newstrspace)
+		errx(1, "string space overflow");
+	memcpy(newstrspace, strspace, strsize/2);
+		/* reclaim memory in the easy, common case. */
+	if (ep == strspace)
+		free(strspace);
+	mstack[sp].sstr = (mstack[sp].sstr-strspace) + newstrspace;
+	ep = (ep-strspace) + newstrspace;
+	strspace = newstrspace;
+	endest = strspace + strsize;
+}
+
+static
+void enlarge_bufspace()
+{
+	pbent *newbuf;
+	int i;
+
+	bufsize *= 2;
+	newbuf = realloc(buf, bufsize*sizeof(pbent));
+	if (!newbuf)
+		errx(1, "too many characters pushed back");
+	for (i = 0; i < MAXINP; i++)
+		bbase[i] = (bbase[i]-buf)+newbuf;
+	bp = (bp-buf)+newbuf;
+	bufbase = (bufbase-buf)+newbuf;
+	buf = newbuf;
+	endpbb = buf+strsize;
+}
+
 /*
  *  chrsave - put single char on string space
  */
@@ -138,10 +207,25 @@ void
 chrsave(c)
 char c;
 {
-	if (ep < endest)
-		*ep++ = c;
+	if (ep >= endest) 
+		enlarge_strspace();
+	*ep++ = c;
+}
+
+/* 
+ * so we reclaim what string space we can
+ */
+char * 
+compute_prevep()
+{
+	if (fp+3 <= low_sp)
+		{
+		return strspace;
+		}
 	else
-		errx(1, "string space overflow");
+		{
+		return mstack[fp+3].sstr;
+		}
 }
 
 /*