///|
fn pdf_cursor_finish_stream_object(
cursor : @core.ByteCursor,
prefix : @syntax.PdfParsedIndirectObject,
) -> @syntax.PdfParsedIndirectObject raise @core.PdfError {
let length_result : Result[Int, Error] = try
pdf_stream_length(prefix.object)
catch {
err => Err(err)
} noraise {
value => Ok(value)
}
match length_result {
Ok(length) =>
pdf_cursor_finish_stream_object_with_length(cursor, prefix, length)
Err(_) => pdf_cursor_finish_malformed_stream_object(cursor, prefix)
}
}
///|
fn pdf_cursor_finish_stream_object_with_length(
cursor : @core.ByteCursor,
prefix : @syntax.PdfParsedIndirectObject,
length : Int,
defer_stream_data? : Bool = false,
) -> @syntax.PdfParsedIndirectObject raise @core.PdfError {
let stream_keyword_position = cursor.absolute_position()
@reader.pdf_cursor_consume_ascii(
cursor,
[115, 116, 114, 101, 97, 109],
ParseStreamExpected,
)
pdf_cursor_consume_stream_start_line_break(cursor)
let data_position = cursor.position()
if cursor.absolute_position() + length > cursor.length() {
raise EndOfInput
}
let stream_data = if defer_stream_data {
cursor.seek_absolute(cursor.absolute_position() + length)
@syntax.StreamToGet(
@syntax.stream_to_get(cursor.deep_copy(), data_position, length),
)
} else {
StreamGot(cursor.read_bytes(length))
}
if !pdf_reader_stream_end_marker_at(cursor.view(), cursor.absolute_position()) {
cursor.seek_absolute(stream_keyword_position)
pdf_cursor_finish_malformed_stream_object(cursor, prefix)
} else {
pdf_cursor_consume_stream_line_break(cursor)
@syntax.pdf_cursor_drop_whitespace(cursor)
@reader.pdf_cursor_consume_ascii(
cursor,
[101, 110, 100, 115, 116, 114, 101, 97, 109],
ParseEndStreamExpected,
)
@syntax.pdf_cursor_drop_whitespace(cursor)
@reader.pdf_cursor_consume_ascii(
cursor,
[101, 110, 100, 111, 98, 106],
ParseEndObjectExpected,
)
{
number: prefix.number,
generation: prefix.generation,
object: @syntax.pdf_stream(prefix.object, stream_data),
}
}
}
///|
fn pdf_cursor_finish_malformed_stream_object(
cursor : @core.ByteCursor,
prefix : @syntax.PdfParsedIndirectObject,
) -> @syntax.PdfParsedIndirectObject raise @core.PdfError {
@reader.pdf_cursor_consume_ascii(
cursor,
[115, 116, 114, 101, 97, 109],
ParseStreamExpected,
)
pdf_cursor_consume_stream_start_line_break(cursor)
let data_start = cursor.absolute_position()
let endstream = @core.pdf_find_ascii_from(cursor.view(), data_start, [
101, 110, 100, 115, 116, 114, 101, 97, 109,
])
if endstream < 0 {
raise ParseEndStreamExpected
}
let data_end = pdf_reader_stream_data_end_before_marker(
cursor.view(),
endstream,
)
let stream_data = cursor
.view_at_absolute(data_start, data_end - data_start)
.to_owned()
cursor.seek_absolute(endstream + 9)
@syntax.pdf_cursor_drop_whitespace(cursor)
@reader.pdf_cursor_consume_ascii(
cursor,
[101, 110, 100, 111, 98, 106],
ParseEndObjectExpected,
)
{
number: prefix.number,
generation: prefix.generation,
object: @syntax.pdf_stream(
prefix.object.add_dict_entry(
@reader.pdf_length_name(),
PdfInteger(stream_data.length()),
),
StreamGot(stream_data),
),
}
}
///|
/// Parse a single indirect stream object from owned bytes.
///
/// The input should contain one indirect-object header, a stream dictionary,
/// stream data, `endstream`, and `endobj`.
pub fn pdf_parse_stream_object_from_bytes(
data : @core.PdfBytes,
) -> @syntax.PdfParsedIndirectObject raise @core.PdfError {
pdf_parse_stream_object_from_view(data)
}
///|
/// Parse a single indirect stream object from a borrowed byte view.
///
/// Malformed `/Length` values are recovered by scanning to `endstream` when
/// possible, matching the stream recovery used by the primitive reader.
pub fn pdf_parse_stream_object_from_view(
data : BytesView,
) -> @syntax.PdfParsedIndirectObject raise @core.PdfError {
let cursor = @core.byte_cursor_of_view(data)
let prefix = @syntax.pdf_parse_indirect_object_prefix_lexemes(
@syntax.pdf_cursor_lex_tokens(cursor),
)
pdf_cursor_finish_stream_object(cursor, prefix)
}