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#include "fitz.h"
#include "mupdf.h"
/* we need to combine all sub-streams into one for the content stream interpreter */
static fz_error
pdf_load_page_contents_array(fz_buffer **bigbufp, pdf_xref *xref, fz_obj *list)
{
fz_error error;
fz_buffer *big;
fz_buffer *one;
int i;
pdf_log_page("multiple content streams: %d\n", fz_array_len(list));
/* TODO: openstream, read, close into big buffer at once */
big = fz_new_buffer(32 * 1024);
for (i = 0; i < fz_array_len(list); i++)
{
fz_obj *stm = fz_array_get(list, i);
error = pdf_load_stream(&one, xref, fz_to_num(stm), fz_to_gen(stm));
if (error)
{
fz_drop_buffer(big);
return fz_rethrow(error, "cannot load content stream part %d/%d (%d %d R)", i + 1, fz_array_len(list), fz_to_num(stm), fz_to_gen(stm));
}
if (big->len + one->len + 1 > big->cap)
fz_resize_buffer(big, big->len + one->len + 1);
memcpy(big->data + big->len, one->data, one->len);
big->data[big->len + one->len] = ' ';
big->len += one->len + 1;
fz_drop_buffer(one);
}
*bigbufp = big;
return fz_okay;
}
static fz_error
pdf_load_page_contents(fz_buffer **bufp, pdf_xref *xref, fz_obj *obj)
{
fz_error error;
if (fz_is_array(obj))
{
error = pdf_load_page_contents_array(bufp, xref, obj);
if (error)
return fz_rethrow(error, "cannot load content stream array (%d 0 R)", fz_to_num(obj));
}
else if (pdf_is_stream(xref, fz_to_num(obj), fz_to_gen(obj)))
{
error = pdf_load_stream(bufp, xref, fz_to_num(obj), fz_to_gen(obj));
if (error)
return fz_rethrow(error, "cannot load content stream (%d 0 R)", fz_to_num(obj));
}
else
{
fz_warn("page contents missing, leaving page blank");
*bufp = fz_new_buffer(0);
}
return fz_okay;
}
/* We need to know whether to install a page-level transparency group */
static int pdf_resources_use_blending(fz_obj *rdb);
static int
pdf_extgstate_uses_blending(fz_obj *dict)
{
fz_obj *obj;
obj = fz_dict_gets(dict, "BM");
if (fz_is_name(obj) && strcmp(fz_to_name(obj), "Normal"))
return 1;
return 0;
}
static int
pdf_pattern_uses_blending(fz_obj *dict)
{
fz_obj *obj;
obj = fz_dict_gets(dict, "Resources");
if (fz_is_dict(obj) && pdf_resources_use_blending(obj))
return 1;
obj = fz_dict_gets(dict, "ExtGState");
if (fz_is_dict(obj) && pdf_extgstate_uses_blending(obj))
return 1;
return 0;
}
static int
pdf_xobject_uses_blending(fz_obj *dict)
{
fz_obj *obj;
obj = fz_dict_gets(dict, "Resources");
if (fz_is_dict(obj) && pdf_resources_use_blending(obj))
return 1;
return 0;
}
static int
pdf_resources_use_blending(fz_obj *rdb)
{
fz_obj *dict;
fz_obj *tmp;
int i;
/* stop on cyclic resource dependencies */
if (fz_dict_gets(rdb, ".useBM"))
return fz_to_bool(fz_dict_gets(rdb, ".useBM"));
tmp = fz_new_bool(0);
fz_dict_puts(rdb, ".useBM", tmp);
fz_drop_obj(tmp);
dict = fz_dict_gets(rdb, "ExtGState");
for (i = 0; i < fz_dict_len(dict); i++)
if (pdf_extgstate_uses_blending(fz_dict_get_val(dict, i)))
goto found;
dict = fz_dict_gets(rdb, "Pattern");
for (i = 0; i < fz_dict_len(dict); i++)
if (pdf_pattern_uses_blending(fz_dict_get_val(dict, i)))
goto found;
dict = fz_dict_gets(rdb, "XObject");
for (i = 0; i < fz_dict_len(dict); i++)
if (pdf_xobject_uses_blending(fz_dict_get_val(dict, i)))
goto found;
return 0;
found:
tmp = fz_new_bool(1);
fz_dict_puts(rdb, ".useBM", tmp);
fz_drop_obj(tmp);
return 1;
}
fz_error
pdf_load_page(pdf_page **pagep, pdf_xref *xref, fz_obj *dict)
{
fz_error error;
pdf_page *page;
fz_obj *obj;
fz_bbox bbox;
pdf_log_page("load page {\n");
// TODO: move this to a more appropriate place
/* Ensure that we have a store for resource objects */
if (!xref->store)
xref->store = pdf_new_store();
page = fz_malloc(sizeof(pdf_page));
page->resources = NULL;
page->contents = NULL;
page->transparency = 0;
page->links = NULL;
page->annots = NULL;
obj = fz_dict_gets(dict, "MediaBox");
bbox = fz_round_rect(pdf_to_rect(obj));
if (fz_is_empty_rect(pdf_to_rect(obj)))
{
fz_warn("cannot find page bounds, guessing page bounds.");
bbox.x0 = 0;
bbox.y0 = 0;
bbox.x1 = 612;
bbox.y1 = 792;
}
obj = fz_dict_gets(dict, "CropBox");
if (fz_is_array(obj))
{
fz_bbox cropbox = fz_round_rect(pdf_to_rect(obj));
bbox = fz_intersect_bbox(bbox, cropbox);
}
page->mediabox.x0 = MIN(bbox.x0, bbox.x1);
page->mediabox.y0 = MIN(bbox.y0, bbox.y1);
page->mediabox.x1 = MAX(bbox.x0, bbox.x1);
page->mediabox.y1 = MAX(bbox.y0, bbox.y1);
if (page->mediabox.x1 - page->mediabox.x0 < 1 || page->mediabox.y1 - page->mediabox.y0 < 1)
return fz_throw("invalid page size");
page->rotate = fz_to_int(fz_dict_gets(dict, "Rotate"));
pdf_log_page("bbox [%d %d %d %d]\n", bbox.x0, bbox.y0, bbox.x1, bbox.y1);
pdf_log_page("rotate %d\n", page->rotate);
obj = fz_dict_gets(dict, "Annots");
if (obj)
{
pdf_load_links(&page->links, xref, obj);
pdf_load_annots(&page->annots, xref, obj);
}
page->resources = fz_dict_gets(dict, "Resources");
if (page->resources)
fz_keep_obj(page->resources);
obj = fz_dict_gets(dict, "Contents");
error = pdf_load_page_contents(&page->contents, xref, obj);
if (error)
{
pdf_free_page(page);
return fz_rethrow(error, "cannot load page contents (%d %d R)", fz_to_num(obj), fz_to_gen(obj));
}
if (page->resources && pdf_resources_use_blending(page->resources))
page->transparency = 1;
pdf_log_page("} %p\n", page);
*pagep = page;
return fz_okay;
}
void
pdf_free_page(pdf_page *page)
{
pdf_log_page("drop page %p\n", page);
if (page->resources)
fz_drop_obj(page->resources);
if (page->contents)
fz_drop_buffer(page->contents);
if (page->links)
pdf_free_link(page->links);
if (page->annots)
pdf_free_annot(page->annots);
fz_free(page);
}
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