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nasm/rdoff/rdoff.c

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/* rdoff.c library of routines for manipulating rdoff files
*
* The Netwide Assembler is copyright (C) 1996 Simon Tatham and
* Julian Hall. All rights reserved. The software is
* redistributable under the license given in the file "LICENSE"
* distributed in the NASM archive.
*
* Permission to use this file in your own projects is granted, as int32_t
* as acknowledgement is given in an appropriate manner to its authors,
* with instructions of how to obtain a copy via ftp.
*/
/* TODO: The functions in this module assume they are running
* on a little-endian machine. This should be fixed to
* make it portable.
*/
#include "compiler.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <inttypes.h>
#define RDOFF_UTILS
#include "rdoff.h"
#define newstr(str) strcpy(malloc(strlen(str) + 1),str)
#define newstrcat(s1,s2) strcat(strcpy(malloc(strlen(s1) + strlen(s2) + 1), \
s1),s2)
/*
* Comment this out to allow the module to read & write header record types
* that it isn't aware of. With this defined, unrecognised header records
* will generate error number 8, reported as 'unknown extended header record'.
*/
#define STRICT_ERRORS
/* ========================================================================
* Code for memory buffers (for delayed writing of header until we know
* how int32_t it is).
* ======================================================================== */
memorybuffer *newmembuf()
{
memorybuffer *t;
t = malloc(sizeof(memorybuffer));
if (!t)
return NULL;
t->length = 0;
t->next = NULL;
return t;
}
void membufwrite(memorybuffer * const b, void *data, int bytes)
{
uint16_t w;
int32_t l;
char *c;
if (b->next) { /* memory buffer full - use next buffer */
membufwrite(b->next, data, bytes);
return;
}
if ((bytes < 0 && b->length - bytes > BUF_BLOCK_LEN)
|| (bytes > 0 && b->length + bytes > BUF_BLOCK_LEN)) {
/* buffer full and no next allocated... allocate and initialise next
* buffer */
b->next = newmembuf();
membufwrite(b->next, data, bytes);
return;
}
switch (bytes) {
case -4: /* convert to little-endian */
l = *(int32_t *)data;
b->buffer[b->length++] = l & 0xFF;
l >>= 8;
b->buffer[b->length++] = l & 0xFF;
l >>= 8;
b->buffer[b->length++] = l & 0xFF;
l >>= 8;
b->buffer[b->length++] = l & 0xFF;
break;
case -2:
w = *(uint16_t *) data;
b->buffer[b->length++] = w & 0xFF;
w >>= 8;
b->buffer[b->length++] = w & 0xFF;
break;
default:
c = data;
while (bytes--)
b->buffer[b->length++] = *c++;
break;
}
}
void membufdump(memorybuffer * b, FILE * fp)
{
if (!b)
return;
fwrite(b->buffer, 1, b->length, fp);
membufdump(b->next, fp);
}
int membuflength(memorybuffer * b)
{
if (!b)
return 0;
return b->length + membuflength(b->next);
}
void freemembuf(memorybuffer * b)
{
if (!b)
return;
freemembuf(b->next);
free(b);
}
/* =========================================================================
General purpose routines and variables used by the library functions
========================================================================= */
/*
* translateint32_t() and translateint16_t()
*
* translate from little endian to local representation
*/
int32_t translateint32_t(int32_t in)
{
int32_t r;
uint8_t *i;
i = (uint8_t *)&in;
r = i[3];
r = (r << 8) + i[2];
r = (r << 8) + i[1];
r = (r << 8) + *i;
return r;
}
uint16_t translateint16_t(uint16_t in)
{
uint16_t r;
uint8_t *i;
i = (uint8_t *)&in;
r = (i[1] << 8) + i[0];
return r;
}
/* Segment types */
static char *knownsegtypes[8] = {
"NULL", "text", "data", "object comment",
"linked comment", "loader comment",
"symbolic debug", "line number debug"
};
/* Get a textual string describing the segment type */
char *translatesegmenttype(uint16_t type)
{
if (type < 8)
return knownsegtypes[type];
if (type < 0x0020)
return "reserved";
if (type < 0x1000)
return "reserved - Moscow";
if (type < 0x8000)
return "reserved - system dependant";
if (type < 0xFFFF)
return "reserved - other";
if (type == 0xFFFF)
return "invalid type code";
return "type code out of range";
}
/* This signature is written to the start of RDOFF files */
const char *RDOFFId = RDOFF2_SIGNATURE;
/* Error messages. Must correspond to the codes defined in rdoff.h */
const char *rdf_errors[11] = {
/* 0 */ "no error occurred",
/* 1 */ "could not open file",
/* 2 */ "invalid file format",
/* 3 */ "error reading file",
/* 4 */ "unknown error",
/* 5 */ "header not read",
/* 6 */ "out of memory",
/* 7 */ "RDOFF v1 not supported",
/* 8 */ "unknown extended header record",
/* 9 */ "header record of known type but unknown length",
/* 10 */ "no such segment"
};
int rdf_errno = 0;
/* ========================================================================
The library functions
======================================================================== */
int rdfopen(rdffile * f, const char *name)
{
FILE *fp;
fp = fopen(name, "rb");
if (!fp)
return rdf_errno = RDF_ERR_OPEN;
return rdfopenhere(f, fp, NULL, name);
}
int rdfopenhere(rdffile * f, FILE * fp, int *refcount, const char *name)
{
char buf[8];
int32_t initpos;
int32_t l;
uint16_t s;
if (translateint32_t(0x01020304) != 0x01020304) {
/* fix this to be portable! */
fputs("*** this program requires a little endian machine\n",
stderr);
fprintf(stderr, "01020304h = %08"PRIx32"h\n", translateint32_t(0x01020304));
exit(3);
}
f->fp = fp;
initpos = ftell(fp);
fread(buf, 6, 1, f->fp); /* read header */
buf[6] = 0;
if (strcmp(buf, RDOFFId)) {
fclose(f->fp);
if (!strcmp(buf, "RDOFF1"))
return rdf_errno = RDF_ERR_VER;
return rdf_errno = RDF_ERR_FORMAT;
}
if (fread(&l, 1, 4, f->fp) != 4
|| fread(&f->header_len, 1, 4, f->fp) != 4) {
fclose(f->fp);
return rdf_errno = RDF_ERR_READ;
}
f->header_ofs = ftell(f->fp);
f->eof_offset = f->header_ofs + translateint32_t(l) - 4;
if (fseek(f->fp, f->header_len, SEEK_CUR)) {
fclose(f->fp);
return rdf_errno = RDF_ERR_FORMAT; /* seek past end of file...? */
}
if (fread(&s, 1, 2, f->fp) != 2) {
fclose(f->fp);
return rdf_errno = RDF_ERR_READ;
}
f->nsegs = 0;
while (s != 0) {
f->seg[f->nsegs].type = s;
if (fread(&f->seg[f->nsegs].number, 1, 2, f->fp) != 2 ||
fread(&f->seg[f->nsegs].reserved, 1, 2, f->fp) != 2 ||
fread(&f->seg[f->nsegs].length, 1, 4, f->fp) != 4) {
fclose(f->fp);
return rdf_errno = RDF_ERR_READ;
}
f->seg[f->nsegs].offset = ftell(f->fp);
if (fseek(f->fp, f->seg[f->nsegs].length, SEEK_CUR)) {
fclose(f->fp);
return rdf_errno = RDF_ERR_FORMAT;
}
f->nsegs++;
if (fread(&s, 1, 2, f->fp) != 2) {
fclose(f->fp);
return rdf_errno = RDF_ERR_READ;
}
}
if (f->eof_offset != ftell(f->fp) + 8) { /* +8 = skip null segment header */
fprintf(stderr, "warning: eof_offset [%"PRId32"] and actual eof offset "
"[%ld] don't match\n", f->eof_offset, ftell(f->fp) + 8);
}
fseek(f->fp, initpos, SEEK_SET);
f->header_loc = NULL;
f->name = newstr(name);
f->refcount = refcount;
if (refcount)
(*refcount)++;
return RDF_OK;
}
int rdfclose(rdffile * f)
{
if (!f->refcount || !--(*f->refcount)) {
fclose(f->fp);
f->fp = NULL;
}
free(f->name);
return 0;
}
/*
* Print the message for last error (from rdf_errno)
*/
void rdfperror(const char *app, const char *name)
{
fprintf(stderr, "%s:%s: %s\n", app, name, rdf_errors[rdf_errno]);
if (rdf_errno == RDF_ERR_OPEN || rdf_errno == RDF_ERR_READ) {
perror(app);
}
}
/*
* Find the segment by its number.
* Returns segment array index, or -1 if segment with such number was not found.
*/
int rdffindsegment(rdffile * f, int segno)
{
int i;
for (i = 0; i < f->nsegs; i++)
if (f->seg[i].number == segno)
return i;
return -1;
}
/*
* Load the segment. Returns status.
*/
int rdfloadseg(rdffile * f, int segment, void *buffer)
{
int32_t fpos;
size_t slen;
switch (segment) {
case RDOFF_HEADER:
fpos = f->header_ofs;
slen = f->header_len;
f->header_loc = (uint8_t *) buffer;
f->header_fp = 0;
break;
default:
if (segment < f->nsegs) {
fpos = f->seg[segment].offset;
slen = f->seg[segment].length;
f->seg[segment].data = (uint8_t *) buffer;
} else {
return rdf_errno = RDF_ERR_SEGMENT;
}
}
if (fseek(f->fp, fpos, SEEK_SET))
return rdf_errno = RDF_ERR_UNKNOWN;
if (fread(buffer, 1, slen, f->fp) != slen)
return rdf_errno = RDF_ERR_READ;
return RDF_OK;
}
/* Macros for reading integers from header in memory */
#define RI8(v) v = f->header_loc[f->header_fp++]
#define RI16(v) { v = (f->header_loc[f->header_fp] + \
(f->header_loc[f->header_fp+1] << 8)); \
f->header_fp += 2; }
#define RI32(v) { v = (f->header_loc[f->header_fp] + \
(f->header_loc[f->header_fp+1] << 8) + \
(f->header_loc[f->header_fp+2] << 16) + \
(f->header_loc[f->header_fp+3] << 24)); \
f->header_fp += 4; }
#define RS(str,max) { for(i=0;i<max;i++){\
RI8(str[i]); if (!str[i]) break;} str[i]=0; }
/*
* Read a header record.
* Returns the address of record, or NULL in case of error.
*/
rdfheaderrec *rdfgetheaderrec(rdffile * f)
{
static rdfheaderrec r;
int i;
if (!f->header_loc) {
rdf_errno = RDF_ERR_HEADER;
return NULL;
}
if (f->header_fp >= f->header_len)
return 0;
RI8(r.type);
RI8(r.g.reclen);
switch (r.type) {
case RDFREC_RELOC: /* Relocation record */
case RDFREC_SEGRELOC:
if (r.r.reclen != 8) {
rdf_errno = RDF_ERR_RECLEN;
return NULL;
}
RI8(r.r.segment);
RI32(r.r.offset);
RI8(r.r.length);
RI16(r.r.refseg);
break;
case RDFREC_IMPORT: /* Imported symbol record */
case RDFREC_FARIMPORT:
RI8(r.i.flags);
RI16(r.i.segment);
RS(r.i.label, EXIM_LABEL_MAX);
break;
case RDFREC_GLOBAL: /* Exported symbol record */
RI8(r.e.flags);
RI8(r.e.segment);
RI32(r.e.offset);
RS(r.e.label, EXIM_LABEL_MAX);
break;
case RDFREC_DLL: /* DLL record */
RS(r.d.libname, MODLIB_NAME_MAX);
break;
case RDFREC_BSS: /* BSS reservation record */
if (r.r.reclen != 4) {
rdf_errno = RDF_ERR_RECLEN;
return NULL;
}
RI32(r.b.amount);
break;
case RDFREC_MODNAME: /* Module name record */
RS(r.m.modname, MODLIB_NAME_MAX);
break;
case RDFREC_COMMON: /* Common variable */
RI16(r.c.segment);
RI32(r.c.size);
RI16(r.c.align);
RS(r.c.label, EXIM_LABEL_MAX);
break;
default:
#ifdef STRICT_ERRORS
rdf_errno = RDF_ERR_RECTYPE; /* unknown header record */
return NULL;
#else
for (i = 0; i < r.g.reclen; i++)
RI8(r.g.data[i]);
#endif
}
return &r;
}
/*
* Rewind to the beginning of the file
*/
void rdfheaderrewind(rdffile * f)
{
f->header_fp = 0;
}
rdf_headerbuf *rdfnewheader(void)
{
rdf_headerbuf *hb = malloc(sizeof(rdf_headerbuf));
if (hb == NULL)
return NULL;
hb->buf = newmembuf();
hb->nsegments = 0;
hb->seglength = 0;
return hb;
}
int rdfaddheader(rdf_headerbuf * h, rdfheaderrec * r)
{
#ifndef STRICT_ERRORS
int i;
#endif
membufwrite(h->buf, &r->type, 1);
membufwrite(h->buf, &r->g.reclen, 1);
switch (r->type) {
case RDFREC_GENERIC: /* generic */
membufwrite(h->buf, &r->g.data, r->g.reclen);
break;
case RDFREC_RELOC:
case RDFREC_SEGRELOC:
membufwrite(h->buf, &r->r.segment, 1);
membufwrite(h->buf, &r->r.offset, -4);
membufwrite(h->buf, &r->r.length, 1);
membufwrite(h->buf, &r->r.refseg, -2); /* 9 bytes written */
break;
case RDFREC_IMPORT: /* import */
case RDFREC_FARIMPORT:
membufwrite(h->buf, &r->i.flags, 1);
membufwrite(h->buf, &r->i.segment, -2);
membufwrite(h->buf, &r->i.label, strlen(r->i.label) + 1);
break;
case RDFREC_GLOBAL: /* export */
membufwrite(h->buf, &r->e.flags, 1);
membufwrite(h->buf, &r->e.segment, 1);
membufwrite(h->buf, &r->e.offset, -4);
membufwrite(h->buf, &r->e.label, strlen(r->e.label) + 1);
break;
case RDFREC_DLL: /* DLL */
membufwrite(h->buf, &r->d.libname, strlen(r->d.libname) + 1);
break;
case RDFREC_BSS: /* BSS */
membufwrite(h->buf, &r->b.amount, -4);
break;
case RDFREC_MODNAME: /* Module name */
membufwrite(h->buf, &r->m.modname, strlen(r->m.modname) + 1);
break;
default:
#ifdef STRICT_ERRORS
return rdf_errno = RDF_ERR_RECTYPE;
#else
for (i = 0; i < r->g.reclen; i++)
membufwrite(h->buf, r->g.data[i], 1);
#endif
}
return 0;
}
int rdfaddsegment(rdf_headerbuf * h, int32_t seglength)
{
h->nsegments++;
h->seglength += seglength;
return 0;
}
int rdfwriteheader(FILE * fp, rdf_headerbuf * h)
{
int32_t l, l2;
fwrite(RDOFFId, 1, strlen(RDOFFId), fp);
l = membuflength(h->buf);
l2 = l + 14 + 10 * h->nsegments + h->seglength;
l = translateint32_t(l);
l2 = translateint32_t(l2);
fwrite(&l2, 4, 1, fp); /* object length */
fwrite(&l, 4, 1, fp); /* header length */
membufdump(h->buf, fp);
return 0; /* no error handling in here... CHANGE THIS! */
}
void rdfdoneheader(rdf_headerbuf * h)
{
freemembuf(h->buf);
free(h);
}
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