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/*
* ORG bytecode
*
* Copyright (C) 2005-2007 Peter Johnson
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND OTHER CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR OTHER CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "util.h"
#include "libyasm-stdint.h"
#include "coretype.h"
#include "file.h"
#include "errwarn.h"
#include "intnum.h"
#include "expr.h"
#include "value.h"
#include "bytecode.h"
typedef struct bytecode_org {
unsigned long start; /* target starting offset within section */
unsigned long fill; /* fill value */
} bytecode_org;
static void bc_org_destroy(void *contents);
static void bc_org_print(const void *contents, FILE *f, int indent_level);
static void bc_org_finalize(yasm_bytecode *bc, yasm_bytecode *prev_bc);
static int bc_org_calc_len(yasm_bytecode *bc, yasm_bc_add_span_func add_span,
void *add_span_data);
static int bc_org_expand(yasm_bytecode *bc, int span, long old_val,
long new_val, /*@out@*/ long *neg_thres,
/*@out@*/ long *pos_thres);
static int bc_org_tobytes(yasm_bytecode *bc, unsigned char **bufp,
unsigned char *bufstart, void *d,
yasm_output_value_func output_value,
/*@null@*/ yasm_output_reloc_func output_reloc);
static const yasm_bytecode_callback bc_org_callback = {
bc_org_destroy,
bc_org_print,
bc_org_finalize,
NULL,
bc_org_calc_len,
bc_org_expand,
bc_org_tobytes,
YASM_BC_SPECIAL_OFFSET
};
static void
bc_org_destroy(void *contents)
{
yasm_xfree(contents);
}
static void
bc_org_print(const void *contents, FILE *f, int indent_level)
{
const bytecode_org *org = (const bytecode_org *)contents;
fprintf(f, "%*s_Org_\n", indent_level, "");
fprintf(f, "%*sStart=%lu\n", indent_level, "", org->start);
}
static void
bc_org_finalize(yasm_bytecode *bc, yasm_bytecode *prev_bc)
{
}
static int
bc_org_calc_len(yasm_bytecode *bc, yasm_bc_add_span_func add_span,
void *add_span_data)
{
bytecode_org *org = (bytecode_org *)bc->contents;
long neg_thres = 0;
long pos_thres = org->start;
if (bc_org_expand(bc, 0, 0, (long)bc->offset, &neg_thres, &pos_thres) < 0)
return -1;
return 0;
}
static int
bc_org_expand(yasm_bytecode *bc, int span, long old_val, long new_val,
/*@out@*/ long *neg_thres, /*@out@*/ long *pos_thres)
{
bytecode_org *org = (bytecode_org *)bc->contents;
/* Check for overrun */
if ((unsigned long)new_val > org->start) {
yasm_error_set(YASM_ERROR_GENERAL,
N_("ORG overlap with already existing data"));
return -1;
}
/* Generate space to start offset */
bc->len = org->start - new_val;
return 1;
}
static int
bc_org_tobytes(yasm_bytecode *bc, unsigned char **bufp,
unsigned char *bufstart, void *d,
yasm_output_value_func output_value,
/*@unused@*/ yasm_output_reloc_func output_reloc)
{
bytecode_org *org = (bytecode_org *)bc->contents;
unsigned long len, i;
/* Sanity check for overrun */
if (bc->offset > org->start) {
yasm_error_set(YASM_ERROR_GENERAL,
N_("ORG overlap with already existing data"));
return 1;
}
len = org->start - bc->offset;
for (i=0; i<len; i++)
YASM_WRITE_8(*bufp, org->fill); /* XXX: handle more than 8 bit? */
return 0;
}
yasm_bytecode *
yasm_bc_create_org(unsigned long start, unsigned long fill, unsigned long line)
{
bytecode_org *org = yasm_xmalloc(sizeof(bytecode_org));
org->start = start;
org->fill = fill;
return yasm_bc_create_common(&bc_org_callback, org, line);
}