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#include "fitz.h"
#include "mupdf.h"
/*
* create xref structure.
* needs to be initialized by initxref, openxref or repairxref.
*/
pdf_xref *
pdf_newxref(void)
{
pdf_xref *xref;
xref = fz_malloc(sizeof(pdf_xref));
memset(xref, 0, sizeof(pdf_xref));
pdf_logxref("newxref %p\n", xref);
xref->file = nil;
xref->version = 13;
xref->startxref = 0;
xref->crypt = nil;
xref->trailer = nil;
xref->root = nil;
xref->info = nil;
xref->store = nil;
xref->cap = 0;
xref->len = 0;
xref->table = nil;
xref->store = nil; /* you need to create this if you want to render */
return xref;
}
void
pdf_closexref(pdf_xref *xref)
{
pdf_logxref("closexref %p\n", xref);
/* don't touch the pdf_store module ... we don't want that dependency here */
if (xref->store)
fz_warn("someone forgot to empty the store before freeing xref!");
if (xref->table)
{
pdf_flushxref(xref, 1);
fz_free(xref->table);
}
if (xref->file)
fz_dropstream(xref->file);
if (xref->trailer)
fz_dropobj(xref->trailer);
if (xref->root)
fz_dropobj(xref->root);
if (xref->info)
fz_dropobj(xref->info);
if (xref->crypt)
pdf_freecrypt(xref->crypt);
fz_free(xref);
}
fz_error
pdf_initxref(pdf_xref *xref)
{
xref->table = fz_malloc(sizeof(pdf_xrefentry) * 128);
xref->cap = 128;
xref->len = 1;
xref->crypt = nil;
xref->table[0].type = 'f';
xref->table[0].ofs = 0;
xref->table[0].gen = 65535;
xref->table[0].stmofs = 0;
xref->table[0].obj = nil;
return fz_okay;
}
void
pdf_flushxref(pdf_xref *xref, int force)
{
int i;
pdf_logxref("flushxref %p (%d)\n", xref, force);
for (i = 0; i < xref->len; i++)
{
if (force)
{
if (xref->table[i].obj)
{
fz_dropobj(xref->table[i].obj);
xref->table[i].obj = nil;
}
}
else
{
if (xref->table[i].obj && xref->table[i].obj->refs == 1)
{
fz_dropobj(xref->table[i].obj);
xref->table[i].obj = nil;
}
}
}
}
void
pdf_debugxref(pdf_xref *xref)
{
int i;
printf("xref\n0 %d\n", xref->len);
for (i = 0; i < xref->len; i++)
{
printf("%010d %05d %c (ref=%d, ofs=%d)\n",
xref->table[i].ofs,
xref->table[i].gen,
xref->table[i].type,
xref->table[i].obj ? xref->table[i].obj->refs : 0,
xref->table[i].stmofs);
}
}
fz_error
pdf_decryptxref(pdf_xref *xref)
{
fz_error error;
fz_obj *encrypt;
fz_obj *id;
encrypt = fz_dictgets(xref->trailer, "Encrypt");
id = fz_dictgets(xref->trailer, "ID");
if (encrypt)
{
if (fz_isnull(encrypt))
return fz_okay;
error = pdf_newcrypt(&xref->crypt, encrypt, id);
if (error)
return fz_rethrow(error, "cannot create decrypter");
}
return fz_okay;
}
/*
* object loading
*/
fz_error
pdf_cacheobject(pdf_xref *xref, int oid, int gen)
{
char buf[65536]; /* yeowch! */
fz_error error;
pdf_xrefentry *x;
int roid, rgen;
if (oid < 0 || oid >= xref->len)
return fz_throw("object out of range (%d %d R); xref size %d", oid, gen, xref->len);
x = &xref->table[oid];
if (x->obj)
return fz_okay;
if (x->type == 'f' || x->type == 'd')
{
x->obj = fz_newnull();
return fz_okay;
}
if (x->type == 'n')
{
error = fz_seek(xref->file, x->ofs, 0);
if (error)
return fz_rethrow(error, "cannot seek to object (%d %d R) offset %d", oid, gen, x->ofs);
error = pdf_parseindobj(&x->obj, xref, xref->file, buf, sizeof buf, &roid, &rgen, &x->stmofs);
if (error)
return fz_rethrow(error, "cannot parse object (%d %d R)", oid, gen);
if (roid != oid)
return fz_throw("found object (%d %d R) instead of (%d %d R)", roid, rgen, oid, gen);
if (xref->crypt)
pdf_cryptobj(xref->crypt, x->obj, oid, gen);
}
else if (x->type == 'o')
{
if (!x->obj)
{
error = pdf_loadobjstm(xref, x->ofs, 0, buf, sizeof buf);
if (error)
return fz_rethrow(error, "cannot load object stream containing object (%d %d R)", oid, gen);
}
}
return fz_okay;
}
fz_error
pdf_loadobject(fz_obj **objp, pdf_xref *xref, int oid, int gen)
{
fz_error error;
error = pdf_cacheobject(xref, oid, gen);
if (error)
return fz_rethrow(error, "cannot load object (%d %d R) into cache", oid, gen);
if (xref->table[oid].obj)
*objp = fz_keepobj(xref->table[oid].obj);
else
{
fz_warn("cannot load missing object (%d %d R), assuming null object", oid, gen);
xref->table[oid].obj = fz_newnull();
}
return fz_okay;
}
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