Import sources from 2011-03-30 iso image

1 files changed, 138 insertions, 0 deletions

diff --git a/sys/src/libmach/8obj.c b/sys/src/libmach/8obj.c
new file mode 100755
index 000000000..54a35c1d0
--- /dev/null
+++ b/sys/src/libmach/8obj.c
@@ -0,0 +1,138 @@
+/*
+ * 8obj.c - identify and parse a 386 object file
+ */
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <mach.h>
+#include "8c/8.out.h"
+#include "obj.h"
+
+typedef struct Addr	Addr;
+struct Addr
+{
+	char	sym;
+	char	flags;
+};
+static	Addr	addr(Biobuf*);
+static	char	type2char(int);
+static	void	skip(Biobuf*, int);
+
+int
+_is8(char *t)
+{
+	uchar *s = (uchar*)t;
+
+	return  s[0] == (ANAME&0xff)			/* aslo = ANAME */
+		&& s[1] == ((ANAME>>8)&0xff)
+		&& s[2] == D_FILE			/* type */
+		&& s[3] == 1				/* sym */
+		&& s[4] == '<';				/* name of file */
+}
+
+int
+_read8(Biobuf *bp, Prog* p)
+{
+	int as, n, c;
+	Addr a;
+
+	as = Bgetc(bp);		/* as(low) */
+	if(as < 0)
+		return 0;
+	c = Bgetc(bp);		/* as(high) */
+	if(c < 0)
+		return 0;
+	as |= ((c & 0xff) << 8);
+	p->kind = aNone;
+	p->sig = 0;
+	if(as == ANAME || as == ASIGNAME){
+		if(as == ASIGNAME){
+			Bread(bp, &p->sig, 4);
+			p->sig = leswal(p->sig);
+		}
+		p->kind = aName;
+		p->type = type2char(Bgetc(bp));		/* type */
+		p->sym = Bgetc(bp);			/* sym */
+		n = 0;
+		for(;;) {
+			as = Bgetc(bp);
+			if(as < 0)
+				return 0;
+			n++;
+			if(as == 0)
+				break;
+		}
+		p->id = malloc(n);
+		if(p->id == 0)
+			return 0;
+		Bseek(bp, -n, 1);
+		if(Bread(bp, p->id, n) != n)
+			return 0;
+		return 1;
+	}
+	if(as == ATEXT)
+		p->kind = aText;
+	if(as == AGLOBL)
+		p->kind = aData;
+	skip(bp, 4);		/* lineno(4) */
+	a = addr(bp);
+	addr(bp);
+	if(!(a.flags & T_SYM))
+		p->kind = aNone;
+	p->sym = a.sym;
+	return 1;
+}
+
+static Addr
+addr(Biobuf *bp)
+{
+	Addr a;
+	int t;
+	long off;
+
+	off = 0;
+	a.sym = -1;
+	a.flags = Bgetc(bp);			/* flags */
+	if(a.flags & T_INDEX)
+		skip(bp, 2);
+	if(a.flags & T_OFFSET){
+		off = Bgetc(bp);
+		off |= Bgetc(bp) << 8;
+		off |= Bgetc(bp) << 16;
+		off |= Bgetc(bp) << 24;
+		if(off < 0)
+			off = -off;
+	}
+	if(a.flags & T_SYM)
+		a.sym = Bgetc(bp);
+	if(a.flags & T_FCONST)
+		skip(bp, 8);
+	else
+	if(a.flags & T_SCONST)
+		skip(bp, NSNAME);
+	if(a.flags & T_TYPE) {
+		t = Bgetc(bp);
+		if(a.sym > 0 && (t==D_PARAM || t==D_AUTO))
+			_offset(a.sym, off);
+	}
+	return a;
+}
+
+static char
+type2char(int t)
+{
+	switch(t){
+	case D_EXTERN:		return 'U';
+	case D_STATIC:		return 'b';
+	case D_AUTO:		return 'a';
+	case D_PARAM:		return 'p';
+	default:		return UNKNOWN;
+	}
+}
+
+static void
+skip(Biobuf *bp, int n)
+{
+	while (n-- > 0)
+		Bgetc(bp);
+}