/* * 7obj.c - identify and parse an arm64 object file */#include <u.h>#include <libc.h>#include <bio.h>#include <mach.h>#include "7c/7.out.h"#include "obj.h" typedef struct Addr	Addr;struct Addr{	char	type;	char	sym;	char	name;};static Addr addr(Biobuf*);static char type2char(int);static void skip(Biobuf*, int); int_is7(char *s){	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_read7(Biobuf *bp, Prog *p){	int as, n;	Addr a; 	as = (uchar)Bgetc(bp);				/* as */	as |= (uchar)Bgetc(bp)<<8;	if(as <= AXXX || as >= ALAST)		return 0;	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;	else if(as == AGLOBL)		p->kind = aData;	n = (uchar)Bgetc(bp);	/* reg and flag (1) */	skip(bp, 4);		/* lineno(4) */	a = addr(bp);	if(n & 0x40)		addr(bp);	/* from3 */	addr(bp);	if(a.type != D_OREG || a.name != D_STATIC && a.name != D_EXTERN)		p->kind = aNone;	p->sym = a.sym;	return 1;} static Addraddr(Biobuf *bp){	Addr a;	long off; 	a.type = Bgetc(bp);	/* a.type */	skip(bp,1);		/* reg */	a.sym = Bgetc(bp);	/* sym index */	a.name = Bgetc(bp);	/* sym type */	switch(a.type){	default:	case D_NONE:	case D_REG:	case D_SP:	case D_FREG:	case D_VREG:	case D_COND:		break; 	case D_OREG:	case D_XPRE:	case D_XPOST:	case D_CONST:	case D_BRANCH:	case D_SHIFT:	case D_EXTREG:	case D_ROFF:	case D_SPR:		off = Bgetc(bp);		off |= Bgetc(bp) << 8;		off |= Bgetc(bp) << 16;		off |= Bgetc(bp) << 24;		if(off < 0)			off = -off;		if(a.sym && (a.name==D_PARAM || a.name==D_AUTO))			_offset(a.sym, off);		break;	case D_DCONST:		skip(bp, 8);		break;	case D_SCONST:		skip(bp, NSNAME);		break;	case D_FCONST:		skip(bp, 8);		break;	}	return a;} static chartype2char(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 voidskip(Biobuf *bp, int n){	while (n-- > 0)		Bgetc(bp);}