quakeforge/tools/qfcc/source/linker.c

/*
	link.c

	qc object file linking

	Copyright (C) 2002 Bill Currie <bill@taniwha.org>

	Author: Bill Currie <bill@taniwha.org>
	Date: 2002/7/3

	This program is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public License
	as published by the Free Software Foundation; either version 2
	of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

	See the GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

*/
static const char rcsid[] =
	"$Id$";

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif
#include <stdlib.h>

#include "QF/hash.h"

#include "def.h"
#include "emit.h"
#include "expr.h"
#include "immediate.h"
#include "obj_file.h"
#include "qfcc.h"
#include "reloc.h"
#include "strpool.h"

static hashtab_t *extern_defs;
static hashtab_t *defined_defs;

static codespace_t *code;
static defspace_t *data;
static defspace_t *far_data;
static strpool_t *strings;
static strpool_t *type_strings;
static struct {
	qfo_reloc_t *relocs;
	int         num_relocs;
	int         max_relocs;
} relocs;
static struct {
	qfo_def_t  *defs;
	int         num_defs;
	int         max_defs;
} defs;
static struct {
	qfo_function_t *funcs;
	int         num_funcs;
	int         max_funcs;
} funcs;
static int      code_base;
static int      data_base;
static int      far_data_base;
static int      reloc_base;
static int      def_base;
static int      func_base;

static const char *
defs_get_key (void *_def, void *unused)
{
	qfo_def_t  *def = (qfo_def_t *) _def;

	return G_GETSTR (def->name);
}

static void
add_strings (qfo_t *qfo)
{
	int         i;

	for (i = 0; i < qfo->strings_size; i += strlen (qfo->strings + i))
		strpool_addstr (strings, qfo->strings + i);
}

static void
add_relocs (qfo_t *qfo)
{
	int         i;

	if (relocs.num_relocs + qfo->num_relocs > relocs.max_relocs) {
		relocs.max_relocs = RUP (relocs.num_relocs + qfo->num_relocs, 16384);
		relocs.relocs = realloc (relocs.relocs,
								 relocs.max_relocs * sizeof (qfo_reloc_t));
	}
	relocs.num_relocs += qfo->num_relocs;
	memcpy (relocs.relocs + reloc_base, qfo->relocs,
			qfo->num_relocs * sizeof (qfo_reloc_t));
	for (i = reloc_base; i < relocs.num_relocs; i++) {
		qfo_reloc_t *reloc = relocs.relocs + i;
		switch ((reloc_type)reloc->type) {
			case rel_none:
				break;
			case rel_op_a_def:
			case rel_op_b_def:
			case rel_op_c_def:
			case rel_op_a_op:
			case rel_op_b_op:
			case rel_op_c_op:
				reloc->ofs += code_base;
				break;
			case rel_def_op:
			case rel_def_def:
			case rel_def_func:
			case rel_def_string:
				reloc->ofs += data_base;
				break;
		}
	}
}

static void
add_defs (qfo_t *qfo)
{
	int         i;

	if (defs.num_defs + qfo->num_defs > defs.max_defs) {
		defs.max_defs = RUP (defs.num_defs + qfo->num_defs, 16384);
		defs.defs = realloc (defs.defs, defs.max_defs * sizeof (qfo_def_t));
	}
	defs.num_defs += qfo->num_defs;
	memcpy (defs.defs + def_base, qfo->defs,
			qfo->num_defs * sizeof (qfo_def_t));
	for (i = def_base; i < defs.num_defs; i++) {
		qfo_def_t *def = defs.defs + i;

		def->full_type = strpool_addstr (type_strings,
										 qfo->types + def->full_type);
		def->name = strpool_addstr (strings, qfo->strings + def->name);
		if (!(def->flags & (QFOD_LOCAL | QFOD_ABSOLUTE))) {
			def->ofs += data_base;
		}
		def->relocs += reloc_base;
		def->file = strpool_addstr (strings, qfo->strings + def->file);

		if (def->flags & QFOD_EXTERNAL) {
			Hash_Add (extern_defs, def);
		} else {
			qfo_def_t  *d;

			if (def->flags & QFOD_GLOBAL) {
				if ((d = Hash_Find (defined_defs, G_GETSTR (def->name)))) {
					pr.source_file = def->file;
					pr.source_line = def->line;
					error (0, "%s redefined", G_GETSTR (def->name));
				}
			}
			if (def->basic_type == ev_string && def->ofs
				&& QFO_var (qfo, string, def->ofs)) {
				string_t    s;
				s = strpool_addstr (strings, QFO_STRING (qfo, def->ofs));
				QFO_var (qfo, string, def->ofs) = s;
			}
			if (def->ofs)
				def->ofs += data_base;
			if (def->flags & QFOD_GLOBAL) {
				while ((d = Hash_Find (extern_defs, G_GETSTR (def->name)))) {
					Hash_Del (extern_defs, G_GETSTR (d->name));
					if (d->full_type != def->full_type) {
						pr.source_file = def->file;
						pr.source_line = def->line;
						error (0, "type mismatch %s %s",
							   G_GETSTR (def->full_type),
							   G_GETSTR (d->full_type));
					}
				}
				Hash_Add (defined_defs, def);
			}
		}
	}
}

static void
add_funcs (qfo_t *qfo)
{
	int         i;

	if (funcs.num_funcs + qfo->num_functions > funcs.max_funcs) {
		funcs.max_funcs = RUP (funcs.num_funcs + qfo->num_functions, 16384);
		funcs.funcs = realloc (funcs.funcs,
								 funcs.max_funcs * sizeof (qfo_function_t));
	}
	funcs.num_funcs += qfo->num_functions;
	memcpy (funcs.funcs + func_base, qfo->functions,
			qfo->num_functions * sizeof (qfo_function_t));
	for (i = func_base; i < funcs.num_funcs; i++) {
		qfo_function_t *func = funcs.funcs + i;
		func->name = strpool_addstr (strings, qfo->strings + func->name);
		func->file = strpool_addstr (strings, qfo->strings + func->file);
		if (func->code)
			func->code += code_base;
		if (func->def)
			func->def += def_base;
		if (func->local_defs)
			func->local_defs += def_base;
		func->relocs += reloc_base;
	}
}

static void
fixup_relocs (qfo_t *qfo)
{
	qfo_reloc_t *reloc;

	for (reloc = relocs.relocs + reloc_base;
		 reloc - relocs.relocs < relocs.num_relocs;
		 reloc++) {
		switch ((reloc_type)reloc->type) {
			case rel_none:
				break;
			case rel_op_a_def:
				code->code[reloc->ofs].a += data_base;
				break;
			case rel_op_b_def:
				code->code[reloc->ofs].b += data_base;
				break;
			case rel_op_c_def:
				code->code[reloc->ofs].c += data_base;
				break;
			case rel_op_a_op:
			case rel_op_b_op:
			case rel_op_c_op:
				break;
			case rel_def_op:
				data->data[reloc->ofs].integer_var += code_base;
				break;
			case rel_def_def:
				data->data[reloc->ofs].integer_var += data_base;
				break;
			case rel_def_func:
				data->data[reloc->ofs].integer_var += func_base;
				break;
			case rel_def_string:
				data->data[reloc->ofs].string_var =
					strpool_addstr (strings,
							qfo->strings + data->data[reloc->ofs].string_var);
				reloc->ofs += data_base;
				break;
		}
	}
}

void
linker_begin (void)
{
	extern_defs = Hash_NewTable (16381, defs_get_key, 0, 0);
	defined_defs = Hash_NewTable (16381, defs_get_key, 0, 0);
	code = codespace_new ();
	data = new_defspace ();
	far_data = new_defspace ();
	strings = strpool_new ();
	type_strings = strpool_new ();
}

void
linker_add_object_file (const char *filename)
{
	qfo_t      *qfo;

	qfo = read_obj_file (filename);
	if (!qfo)
		return;  

	puts(filename);

	code_base = code->size;
	data_base = data->size;
	far_data_base = far_data->size;
	reloc_base = relocs.num_relocs;
	def_base = defs.num_defs;
	func_base = funcs.num_funcs;

	codespace_addcode (code, qfo->code, qfo->code_size);
	defspace_adddata (data, qfo->data, qfo->data_size);
	defspace_adddata (far_data, qfo->far_data, qfo->far_data_size);
	add_strings (qfo);
	add_relocs (qfo);
	add_defs (qfo);
	add_funcs (qfo);

	fixup_relocs (qfo);
	
	qfo_delete (qfo);

	qfo = qfo_new ();
	qfo_add_code (qfo, code->code, code->size);
	qfo_add_data (qfo, data->data, data->size);
	qfo_add_far_data (qfo, far_data->data, far_data->size);
	qfo_add_strings (qfo, strings->strings, strings->size);
	qfo_add_relocs (qfo, relocs.relocs, relocs.num_relocs);
	qfo_add_defs (qfo, defs.defs, defs.num_defs);
	qfo_add_functions (qfo, funcs.funcs, funcs.num_funcs);
	qfo_add_types (qfo, type_strings->strings, type_strings->size);
}

void
linker_finish (void)
{
	qfo_def_t **undef_defs, **def;
	undef_defs = (qfo_def_t **) Hash_GetList (extern_defs);
	for (def = undef_defs; *def; def++) {
		pr.source_file = (*def)->file;
		pr.source_line = (*def)->line;
		error (0, "undefined symbol %s", G_GETSTR ((*def)->name));
	}
}