src/libmach/obj.c - go - Git at Google

 // Inferno libmach/obj.c
 // http://code.google.com/p/inferno-os/source/browse/utils/libmach/obj.c
 //
 // 	Copyright © 1994-1999 Lucent Technologies Inc.
 // 	Power PC support Copyright © 1995-2004 C H Forsyth (forsyth@terzarima.net).
 // 	Portions Copyright © 1997-1999 Vita Nuova Limited.
 // 	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com).
 // 	Revisions Copyright © 2000-2004 Lucent Technologies Inc. and others.
 //	Portions Copyright © 2009 The Go Authors.  All rights reserved.
 //
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
 // in the Software without restriction, including without limitation the rights
 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 // copies of the Software, and to permit persons to whom the Software is
 // furnished to do so, subject to the following conditions:
 //
 // The above copyright notice and this permission notice shall be included in
 // all copies or substantial portions of the Software.
 //
 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.

 /*
  * obj.c
  * routines universal to all object files
  */
 #include <u.h>
 #include <libc.h>
 #include <bio.h>
 #include <ar.h>
 #include <mach.h>
 #include "obj.h"

 #define islocal(t)	((t)=='a' || (t)=='p')

 enum
 {
 	NNAMES	= 50,
 	MAXIS	= 8,		/* max length to determine if a file is a .? file */
 	MAXOFF	= 0x7fffffff,	/* larger than any possible local offset */
 	NHASH	= 1024,		/* must be power of two */
 	HASHMUL	= 79L,
 };

 int	_is2(char*),		/* in [$OS].c */
 	_is5(char*),
 	_is6(char*),
 	_is7(char*),
 	_is8(char*),
 	_is9(char*),
 	_isk(char*),
 	_isq(char*),
 	_isv(char*),
 	_isu(char*),
 	_read2(Biobuf*, Prog*),
 	_read5(Biobuf*, Prog*),
 	_read6(Biobuf*, Prog*),
 	_read7(Biobuf*, Prog*),
 	_read8(Biobuf*, Prog*),
 	_read9(Biobuf*, Prog*),
 	_readk(Biobuf*, Prog*),
 	_readq(Biobuf*, Prog*),
 	_readv(Biobuf*, Prog*),
 	_readu(Biobuf*, Prog*);

 typedef struct Obj	Obj;
 typedef struct Symtab	Symtab;

 struct	Obj		/* functions to handle each intermediate (.$O) file */
 {
 	char	*name;				/* name of each $O file */
 	int	(*is)(char*);			/* test for each type of $O file */
 	int	(*read)(Biobuf*, Prog*);	/* read for each type of $O file*/
 };

 static Obj	obj[] =
 {			/* functions to identify and parse each type of obj */
 	[Obj68020]   = { "68020 .2",	_is2, _read2 },
 	[ObjAmd64]   = { "amd64 .6",	_is6 , _read6 },
 	[ObjArm]     = { "arm .5",	_is5, _read5 },
 	[ObjAlpha]   = { "alpha .7",	_is7, _read7 },
 	[Obj386]     = { "386 .8",	_is8, _read8 },
 	[ObjSparc]   = { "sparc .k",	_isk, _readk },
 	[ObjPower]   = { "power .q",	_isq, _readq },
 	[ObjMips]    = { "mips .v",	_isv, _readv },
 	[ObjSparc64] = { "sparc64 .u",  _isu, _readu },
 	[ObjPower64] = { "power64 .9",	_is9, _read9 },
 	[Maxobjtype] = { 0, 0, 0 }
 };

 struct	Symtab
 {
 	struct	Sym 	s;
 	struct	Symtab	*next;
 };

 static	Symtab *hash[NHASH];
 static	Sym	*names[NNAMES];	/* working set of active names */

 static	int	processprog(Prog*,int);	/* decode each symbol reference */
 static	void	objreset(void);
 static	void	objlookup(int, char *, int, uint);
 static	void 	objupdate(int, int);

 static	int	sequence;

 int
 objtype(Biobuf *bp, char **name)
 {
 	int i;
 	char buf[MAXIS];
 	int c;
 	char *p;

 	/*
 	 * Look for import block.
 	 */
 	p = Brdline(bp, '\n');
 	if(p == nil)
 		return -1;
 	if(Blinelen(bp) < 10 || strncmp(p, "go object ", 10) != 0)
 		return -1;
 	Bseek(bp, -1, 1);

 	/*
 	 * Found one.  Skip until "\n!\n"
 	 */
 	for(;;) {
 		if((c = Bgetc(bp)) == Beof)
 			return -1;
 		if(c != '\n')
 			continue;
 		c = Bgetc(bp);
 		if(c != '!'){
 			Bungetc(bp);
 			continue;
 		}
 		c = Bgetc(bp);
 		if(c != '\n'){
 			Bungetc(bp);
 			continue;
 		}
 		break;
 	}

 	if(Bread(bp, buf, MAXIS) < MAXIS)
 		return -1;
 	Bseek(bp, -MAXIS, 1);
 	for (i = 0; i < Maxobjtype; i++) {
 		if (obj[i].is && (*obj[i].is)(buf)) {
 			if (name)
 				*name = obj[i].name;
 			return i;
 		}
 	}

 	return -1;
 }

 int
 isar(Biobuf *bp)
 {
 	int n;
 	char magbuf[SARMAG];

 	n = Bread(bp, magbuf, SARMAG);
 	if(n == SARMAG && strncmp(magbuf, ARMAG, SARMAG) == 0)
 		return 1;
 	return 0;
 }

 /*
  * determine what kind of object file this is and process it.
  * return whether or not this was a recognized intermediate file.
  */
 int
 readobj(Biobuf *bp, int objtype)
 {
 	Prog p;

 	if (objtype < 0 || objtype >= Maxobjtype || obj[objtype].is == 0)
 		return 1;
 	objreset();
 	while ((*obj[objtype].read)(bp, &p))
 		if (!processprog(&p, 1))
 			return 0;
 	return 1;
 }

 int
 readar(Biobuf *bp, int objtype, vlong end, int doautos)
 {
 	Prog p;

 	if (objtype < 0 || objtype >= Maxobjtype || obj[objtype].is == 0)
 		return 1;
 	objreset();
 	while ((*obj[objtype].read)(bp, &p) && Boffset(bp) < end)
 		if (!processprog(&p, doautos))
 			return 0;
 	return 1;
 }

 /*
  *	decode a symbol reference or definition
  */
 static	int
 processprog(Prog *p, int doautos)
 {
 	if(p->kind == aNone)
 		return 1;
 	if((schar)p->sym < 0 || p->sym >= NNAMES)
 		return 0;
 	switch(p->kind)
 	{
 	case aName:
 		if (!doautos)
 		if(p->type != 'U' && p->type != 'b')
 			break;
 		objlookup(p->sym, p->id, p->type, p->sig);
 		break;
 	case aText:
 		objupdate(p->sym, 'T');
 		break;
 	case aData:
 		objupdate(p->sym, 'D');
 		break;
 	default:
 		break;
 	}
 	return 1;
 }

 /*
  * find the entry for s in the symbol array.
  * make a new entry if it is not already there.
  */
 static void
 objlookup(int id, char *name, int type, uint sig)
 {
 	int32 h;
 	char *cp;
 	Sym *s;
 	Symtab *sp;

 	s = names[id];
 	if(s && strcmp(s->name, name) == 0) {
 		s->type = type;
 		s->sig = sig;
 		return;
 	}

 	h = *name;
 	for(cp = name+1; *cp; h += *cp++)
 		h *= HASHMUL;
 	h &= NHASH-1;
 	if (type == 'U' || type == 'b' || islocal(type)) {
 		for(sp = hash[h]; sp; sp = sp->next)
 			if(strcmp(sp->s.name, name) == 0) {
 				switch(sp->s.type) {
 				case 'T':
 				case 'D':
 				case 'U':
 					if (type == 'U') {
 						names[id] = &sp->s;
 						return;
 					}
 					break;
 				case 't':
 				case 'd':
 				case 'b':
 					if (type == 'b') {
 						names[id] = &sp->s;
 						return;
 					}
 					break;
 				case 'a':
 				case 'p':
 					if (islocal(type)) {
 						names[id] = &sp->s;
 						return;
 					}
 					break;
 				default:
 					break;
 				}
 			}
 	}
 	sp = malloc(sizeof(Symtab));
 	if(sp == nil)
 		sysfatal("out of memory");
 	sp->s.name = name;
 	sp->s.type = type;
 	sp->s.sig = sig;
 	sp->s.value = islocal(type) ? MAXOFF : 0;
 	sp->s.sequence = sequence++;
 	names[id] = &sp->s;
 	sp->next = hash[h];
 	hash[h] = sp;
 	return;
 }
 /*
  *	traverse the symbol lists
  */
 void
 objtraverse(void (*fn)(Sym*, void*), void *pointer)
 {
 	int i;
 	Symtab *s;

 	for(i = 0; i < NHASH; i++)
 		for(s = hash[i]; s; s = s->next)
 			(*fn)(&s->s, pointer);
 }

 /*
  * update the offset information for a 'a' or 'p' symbol in an intermediate file
  */
 void
 _offset(int id, vlong off)
 {
 	Sym *s;

 	s = names[id];
 	if (s && s->name[0] && islocal(s->type) && s->value > off)
 		s->value = off;
 }

 /*
  * update the type of a global text or data symbol
  */
 static void
 objupdate(int id, int type)
 {
 	Sym *s;

 	s = names[id];
 	if (s && s->name[0])
 		if (s->type == 'U')
 			s->type = type;
 		else if (s->type == 'b')
 			s->type = tolower(type);
 }

 /*
  * look for the next file in an archive
  */
 int
 nextar(Biobuf *bp, int offset, char *buf)
 {
 	struct ar_hdr a;
 	int i, r;
 	int32 arsize;

 	if (offset&01)
 		offset++;
 	Bseek(bp, offset, 0);
 	r = Bread(bp, &a, SAR_HDR);
 	if(r != SAR_HDR)
 		return 0;
 	if(strncmp(a.fmag, ARFMAG, sizeof(a.fmag)))
 		return -1;
 	for(i=0; i<sizeof(a.name) && i<SARNAME && a.name[i] != ' '; i++)
 		buf[i] = a.name[i];
 	buf[i] = 0;
 	arsize = strtol(a.size, 0, 0);
 	if (arsize&1)
 		arsize++;
 	return arsize + SAR_HDR;
 }

 static void
 objreset(void)
 {
 	int i;
 	Symtab *s, *n;

 	for(i = 0; i < NHASH; i++) {
 		for(s = hash[i]; s; s = n) {
 			n = s->next;
 			free(s->s.name);
 			free(s);
 		}
 		hash[i] = 0;
 	}
 	memset(names, 0, sizeof names);
 }
	// Inferno libmach/obj.c
	// http://code.google.com/p/inferno-os/source/browse/utils/libmach/obj.c
	//
	// Copyright © 1994-1999 Lucent Technologies Inc.
	// Power PC support Copyright © 1995-2004 C H Forsyth (forsyth@terzarima.net).
	// Portions Copyright © 1997-1999 Vita Nuova Limited.
	// Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com).
	// Revisions Copyright © 2000-2004 Lucent Technologies Inc. and others.
	// Portions Copyright © 2009 The Go Authors. All rights reserved.
	//
	// Permission is hereby granted, free of charge, to any person obtaining a copy
	// of this software and associated documentation files (the "Software"), to deal
	// in the Software without restriction, including without limitation the rights
	// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	// copies of the Software, and to permit persons to whom the Software is
	// furnished to do so, subject to the following conditions:
	//
	// The above copyright notice and this permission notice shall be included in
	// all copies or substantial portions of the Software.
	//
	// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	// THE SOFTWARE.

	/*
	* obj.c
	* routines universal to all object files
	*/
	#include <u.h>
	#include <libc.h>
	#include <bio.h>
	#include <ar.h>
	#include <mach.h>
	#include "obj.h"

	#define islocal(t) ((t)=='a' \|\| (t)=='p')

	enum
	{
	NNAMES = 50,
	MAXIS = 8, /* max length to determine if a file is a .? file */
	MAXOFF = 0x7fffffff, /* larger than any possible local offset */
	NHASH = 1024, /* must be power of two */
	HASHMUL = 79L,
	};

	int _is2(char), / in [$OS].c */
	_is5(char*),
	_is6(char*),
	_is7(char*),
	_is8(char*),
	_is9(char*),
	_isk(char*),
	_isq(char*),
	_isv(char*),
	_isu(char*),
	_read2(Biobuf, Prog),
	_read5(Biobuf, Prog),
	_read6(Biobuf, Prog),
	_read7(Biobuf, Prog),
	_read8(Biobuf, Prog),
	_read9(Biobuf, Prog),
	_readk(Biobuf, Prog),
	_readq(Biobuf, Prog),
	_readv(Biobuf, Prog),
	_readu(Biobuf, Prog);

	typedef struct Obj Obj;
	typedef struct Symtab Symtab;

	struct Obj /* functions to handle each intermediate (.$O) file */
	{
	char name; / name of each $O file */
	int (is)(char); /* test for each type of $O file */
	int (read)(Biobuf, Prog); / read for each type of $O file*/
	};

	static Obj obj[] =
	{ /* functions to identify and parse each type of obj */
	[Obj68020] = { "68020 .2", _is2, _read2 },
	[ObjAmd64] = { "amd64 .6", _is6 , _read6 },
	[ObjArm] = { "arm .5", _is5, _read5 },
	[ObjAlpha] = { "alpha .7", _is7, _read7 },
	[Obj386] = { "386 .8", _is8, _read8 },
	[ObjSparc] = { "sparc .k", _isk, _readk },
	[ObjPower] = { "power .q", _isq, _readq },
	[ObjMips] = { "mips .v", _isv, _readv },
	[ObjSparc64] = { "sparc64 .u", _isu, _readu },
	[ObjPower64] = { "power64 .9", _is9, _read9 },
	[Maxobjtype] = { 0, 0, 0 }
	};

	struct Symtab
	{
	struct Sym s;
	struct Symtab *next;
	};

	static Symtab *hash[NHASH];
	static Sym names[NNAMES]; / working set of active names */

	static int processprog(Prog,int); / decode each symbol reference */
	static void objreset(void);
	static void objlookup(int, char *, int, uint);
	static void objupdate(int, int);

	static int sequence;

	int
	objtype(Biobuf bp, char *name)
	{
	int i;
	char buf[MAXIS];
	int c;
	char *p;

	/*
	* Look for import block.
	*/
	p = Brdline(bp, '\n');
	if(p == nil)
	return -1;
	if(Blinelen(bp) < 10 \|\| strncmp(p, "go object ", 10) != 0)
	return -1;
	Bseek(bp, -1, 1);

	/*
	* Found one. Skip until "\n!\n"
	*/
	for(;;) {
	if((c = Bgetc(bp)) == Beof)
	return -1;
	if(c != '\n')
	continue;
	c = Bgetc(bp);
	if(c != '!'){
	Bungetc(bp);
	continue;
	}
	c = Bgetc(bp);
	if(c != '\n'){
	Bungetc(bp);
	continue;
	}
	break;
	}

	if(Bread(bp, buf, MAXIS) < MAXIS)
	return -1;
	Bseek(bp, -MAXIS, 1);
	for (i = 0; i < Maxobjtype; i++) {
	if (obj[i].is && (*obj[i].is)(buf)) {
	if (name)
	*name = obj[i].name;
	return i;
	}
	}

	return -1;
	}

	int
	isar(Biobuf *bp)
	{
	int n;
	char magbuf[SARMAG];

	n = Bread(bp, magbuf, SARMAG);
	if(n == SARMAG && strncmp(magbuf, ARMAG, SARMAG) == 0)
	return 1;
	return 0;
	}

	/*
	* determine what kind of object file this is and process it.
	* return whether or not this was a recognized intermediate file.
	*/
	int
	readobj(Biobuf *bp, int objtype)
	{
	Prog p;

	if (objtype < 0 \|\| objtype >= Maxobjtype \|\| obj[objtype].is == 0)
	return 1;
	objreset();
	while ((*obj[objtype].read)(bp, &p))
	if (!processprog(&p, 1))
	return 0;
	return 1;
	}

	int
	readar(Biobuf *bp, int objtype, vlong end, int doautos)
	{
	Prog p;

	if (objtype < 0 \|\| objtype >= Maxobjtype \|\| obj[objtype].is == 0)
	return 1;
	objreset();
	while ((*obj[objtype].read)(bp, &p) && Boffset(bp) < end)
	if (!processprog(&p, doautos))
	return 0;
	return 1;
	}

	/*
	* decode a symbol reference or definition
	*/
	static int
	processprog(Prog *p, int doautos)
	{
	if(p->kind == aNone)
	return 1;
	if((schar)p->sym < 0 \|\| p->sym >= NNAMES)
	return 0;
	switch(p->kind)
	{
	case aName:
	if (!doautos)
	if(p->type != 'U' && p->type != 'b')
	break;
	objlookup(p->sym, p->id, p->type, p->sig);
	break;
	case aText:
	objupdate(p->sym, 'T');
	break;
	case aData:
	objupdate(p->sym, 'D');
	break;
	default:
	break;
	}
	return 1;
	}

	/*
	* find the entry for s in the symbol array.
	* make a new entry if it is not already there.
	*/
	static void
	objlookup(int id, char *name, int type, uint sig)
	{
	int32 h;
	char *cp;
	Sym *s;
	Symtab *sp;

	s = names[id];
	if(s && strcmp(s->name, name) == 0) {
	s->type = type;
	s->sig = sig;
	return;
	}

	h = *name;
	for(cp = name+1; cp; h += cp++)
	h *= HASHMUL;
	h &= NHASH-1;
	if (type == 'U' \|\| type == 'b' \|\| islocal(type)) {
	for(sp = hash[h]; sp; sp = sp->next)
	if(strcmp(sp->s.name, name) == 0) {
	switch(sp->s.type) {
	case 'T':
	case 'D':
	case 'U':
	if (type == 'U') {
	names[id] = &sp->s;
	return;
	}
	break;
	case 't':
	case 'd':
	case 'b':
	if (type == 'b') {
	names[id] = &sp->s;
	return;
	}
	break;
	case 'a':
	case 'p':
	if (islocal(type)) {
	names[id] = &sp->s;
	return;
	}
	break;
	default:
	break;
	}
	}
	}
	sp = malloc(sizeof(Symtab));
	if(sp == nil)
	sysfatal("out of memory");
	sp->s.name = name;
	sp->s.type = type;
	sp->s.sig = sig;
	sp->s.value = islocal(type) ? MAXOFF : 0;
	sp->s.sequence = sequence++;
	names[id] = &sp->s;
	sp->next = hash[h];
	hash[h] = sp;
	return;
	}
	/*
	* traverse the symbol lists
	*/
	void
	objtraverse(void (fn)(Sym, void), void pointer)
	{
	int i;
	Symtab *s;

	for(i = 0; i < NHASH; i++)
	for(s = hash[i]; s; s = s->next)
	(*fn)(&s->s, pointer);
	}

	/*
	* update the offset information for a 'a' or 'p' symbol in an intermediate file
	*/
	void
	_offset(int id, vlong off)
	{
	Sym *s;

	s = names[id];
	if (s && s->name[0] && islocal(s->type) && s->value > off)
	s->value = off;
	}

	/*
	* update the type of a global text or data symbol
	*/
	static void
	objupdate(int id, int type)
	{
	Sym *s;

	s = names[id];
	if (s && s->name[0])
	if (s->type == 'U')
	s->type = type;
	else if (s->type == 'b')
	s->type = tolower(type);
	}

	/*
	* look for the next file in an archive
	*/
	int
	nextar(Biobuf bp, int offset, char buf)
	{
	struct ar_hdr a;
	int i, r;
	int32 arsize;

	if (offset&01)
	offset++;
	Bseek(bp, offset, 0);
	r = Bread(bp, &a, SAR_HDR);
	if(r != SAR_HDR)
	return 0;
	if(strncmp(a.fmag, ARFMAG, sizeof(a.fmag)))
	return -1;
	for(i=0; i<sizeof(a.name) && i<SARNAME && a.name[i] != ' '; i++)
	buf[i] = a.name[i];
	buf[i] = 0;
	arsize = strtol(a.size, 0, 0);
	if (arsize&1)
	arsize++;
	return arsize + SAR_HDR;
	}

	static void
	objreset(void)
	{
	int i;
	Symtab s, n;

	for(i = 0; i < NHASH; i++) {
	for(s = hash[i]; s; s = n) {
	n = s->next;
	free(s->s.name);
	free(s);
	}
	hash[i] = 0;
	}
	memset(names, 0, sizeof names);
	}