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#include "fitz.h"
#include "mupdf.h"
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->crypt)
pdf_freecrypt(xref->crypt);
fz_free(xref);
}
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);
}
}
/*
* compressed object streams
*/
static fz_error
pdf_loadobjstm(pdf_xref *xref, int num, int gen, char *buf, int cap)
{
fz_error error;
fz_stream *stm;
fz_obj *objstm;
int *numbuf;
int *ofsbuf;
fz_obj *obj;
int first;
int count;
int i, n;
pdf_token_e tok;
pdf_logxref("loadobjstm (%d %d R)\n", num, gen);
error = pdf_loadobject(&objstm, xref, num, gen);
if (error)
return fz_rethrow(error, "cannot load object stream object (%d %d R)", num, gen);
count = fz_toint(fz_dictgets(objstm, "N"));
first = fz_toint(fz_dictgets(objstm, "First"));
pdf_logxref(" count %d\n", count);
numbuf = fz_malloc(count * sizeof(int));
ofsbuf = fz_malloc(count * sizeof(int));
error = pdf_openstream(&stm, xref, num, gen);
if (error)
{
error = fz_rethrow(error, "cannot open object stream (%d %d R)", num, gen);
goto cleanupbuf;
}
for (i = 0; i < count; i++)
{
error = pdf_lex(&tok, stm, buf, cap, &n);
if (error || tok != PDF_TINT)
{
error = fz_rethrow(error, "corrupt object stream (%d %d R)", num, gen);
goto cleanupstm;
}
numbuf[i] = atoi(buf);
error = pdf_lex(&tok, stm, buf, cap, &n);
if (error || tok != PDF_TINT)
{
error = fz_rethrow(error, "corrupt object stream (%d %d R)", num, gen);
goto cleanupstm;
}
ofsbuf[i] = atoi(buf);
}
error = fz_seek(stm, first, 0);
if (error)
{
error = fz_rethrow(error, "cannot seek in object stream (%d %d R)", num, gen);
goto cleanupstm;
}
for (i = 0; i < count; i++)
{
/* FIXME: seek to first + ofsbuf[i] */
error = pdf_parsestmobj(&obj, xref, stm, buf, cap);
if (error)
{
error = fz_rethrow(error, "cannot parse object %d in stream (%d %d R)", i, num, gen);
goto cleanupstm;
}
if (numbuf[i] < 1 || numbuf[i] >= xref->len)
{
fz_dropobj(obj);
error = fz_throw("object id (%d 0 R) out of range (0..%d)", numbuf[i], xref->len - 1);
goto cleanupstm;
}
if (xref->table[numbuf[i]].type == 'o' && xref->table[numbuf[i]].ofs == num)
{
if (xref->table[numbuf[i]].obj)
fz_dropobj(xref->table[numbuf[i]].obj);
xref->table[numbuf[i]].obj = obj;
}
else
{
fz_dropobj(obj);
}
}
fz_dropstream(stm);
fz_free(ofsbuf);
fz_free(numbuf);
fz_dropobj(objstm);
return fz_okay;
cleanupstm:
fz_dropstream(stm);
cleanupbuf:
fz_free(ofsbuf);
fz_free(numbuf);
fz_dropobj(objstm);
return error; /* already rethrown */
}
/*
* object loading
*/
fz_error
pdf_cacheobject(pdf_xref *xref, int num, int gen)
{
fz_error error;
pdf_xrefentry *x;
int rnum, rgen;
if (num < 0 || num >= xref->len)
return fz_throw("object out of range (%d %d R); xref size %d", num, gen, xref->len);
x = &xref->table[num];
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", num, gen, x->ofs);
error = pdf_parseindobj(&x->obj, xref, xref->file, xref->scratch, sizeof xref->scratch,
&rnum, &rgen, &x->stmofs);
if (error)
return fz_rethrow(error, "cannot parse object (%d %d R)", num, gen);
if (rnum != num)
return fz_throw("found object (%d %d R) instead of (%d %d R)", rnum, rgen, num, gen);
if (xref->crypt)
pdf_cryptobj(xref->crypt, x->obj, num, gen);
}
else if (x->type == 'o')
{
if (!x->obj)
{
error = pdf_loadobjstm(xref, x->ofs, 0, xref->scratch, sizeof xref->scratch);
if (error)
return fz_rethrow(error, "cannot load object stream containing object (%d %d R)", num, gen);
}
}
return fz_okay;
}
fz_error
pdf_loadobject(fz_obj **objp, pdf_xref *xref, int num, int gen)
{
fz_error error;
error = pdf_cacheobject(xref, num, gen);
if (error)
return fz_rethrow(error, "cannot load object (%d %d R) into cache", num, gen);
if (xref->table[num].obj)
*objp = fz_keepobj(xref->table[num].obj);
else
{
fz_warn("cannot load missing object (%d %d R), assuming null object", num, gen);
xref->table[num].obj = fz_newnull();
*objp = fz_keepobj(xref->table[num].obj);
}
return fz_okay;
}
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