Module reader 

Endianness

PSD is big-endian. Upstream calls DataView.getInt16/getUint16/getInt32/ getUint32/getFloat32/getFloat64 with the littleEndian argument either omitted or explicitly false (e.g. getInt16(off, false)), which means big-endian. The few *LE variants pass true. This port reproduces that: all default readers use from_be_bytes, the _le variants use from_le_bytes.

Error strategy

Upstream throws Error in a handful of places (checkSignature, readSection overflow, warnOrThrow when strict, the >100MB guard in readBytes). It also reads past the end of a slice in some “broken file” recovery paths. We model fallible operations as Result<T, ReadError> with a small crate-local ReadError enum, returned consistently from every primitive that can fail. This is preferred over panicking because callers (the future document orchestration) need to distinguish recoverable from fatal conditions, mirroring upstream’s strict/warnOrThrow split.

Structs

DecodeTarget

Pixel storage backing a PixelData during decode, tracking bit depth so the channel codecs can write at the correct stride.

PsdReader

Состояние низкоуровневого ридера (зеркало TS interface PsdReader extends ReadOptions).

Enums

ReadError

Ошибки низкоуровневого ридера (зеркало throw new Error(...) из upstream).

Functions

check_signature

Зеркало checkSignature(reader, a, b?).

peek_uint8

Зеркало peekUint8 — читает без сдвига курсора.

peek_uint32

Хелпер peekUint32 — задача упоминает его наличие; в upstream отдельной функции нет, но peek-семантика (чтение без сдвига курсора) полезна и согласуется с peekUint8. Big-endian.

read_ascii_string

Зеркало readAsciiString(reader, length).

read_bytes

Зеркало readBytes(reader, length).

read_bytes_slice

Zero-copy вариант чтения байтов: возвращает под-срез исходного буфера.

read_color

Consolidated readColor. NOTE (see report): effects_helpers, image_resources, additional_info::adjustment_keys, and additional_info::misc_keys each keep a LOCAL copy of this function (they cannot reach reader-internal helpers). Those should switch to this in a later cleanup task; not edited now.

read_data_raw

Mirror readDataRaw. Down-converts 16/32-bit samples to 8-bit (top byte).

read_data_rle

Mirror readDataRLE (PackBits). Writes one byte per sample to the 8-bit RGBA target. For >8 bit depths the source is still byte-stream PackBits, so we keep upstream’s byte semantics (the upstream RLE path also writes bytes).

read_data_zip

Mirror readDataZip (zlib via flate2).

read_fixed_point32

Зеркало readFixedPoint32 — 32-битное число с фиксированной точкой 16.16.

read_fixed_point_path32

Зеркало readFixedPointPath32 — 32-битное число с фиксированной точкой 8.24.

read_float32

read_float64

read_int8

Upstream имеет readInt8? Нет отдельной функции, но задание просит её — реализуем через интерпретацию байта как знакового (DataView.getInt8).

read_int16

read_int32

read_int32_le

Зеркало readInt32LE (little-endian).

read_pascal_string

Зеркало readPascalString(reader, padTo).

read_pattern

Consolidated readPattern. NOTE (see report): abr.rs and smart_object_keys.rs hold local copies; they should switch to this later.

read_psd

High-level entry point. Mirror of upstream readPsd(reader, readOptions), but takes a byte slice + options and builds a PsdReader internally.

read_psd_from_reader

Mirror of upstream readPsd operating on an existing reader (options must already be set on the reader, as upstream does via Object.assign).

read_section

Зеркало readSection<T>(reader, round, func, skipEmpty = true, eightBytes = false).

read_short_string

Зеркало приватной readShortString(reader, length).

read_signature

Зеркало readSignature(reader) — 4-байтовая подпись.

read_uint8

read_uint16

read_uint32

read_uint16_le

Зеркало readUint16LE (little-endian).

read_unicode_string

Зеркало readUnicodeString(reader) — uint32 длина (в code unit’ах), затем строка.

read_unicode_string_with_length

Зеркало readUnicodeStringWithLength(reader, length) (big-endian uint16 code units).

read_unicode_string_with_length_le

Зеркало readUnicodeStringWithLengthLE (little-endian uint16 code units).

skip_bytes

Зеркало skipBytes(reader, count).

valid_signature_at

Зеркало validSignatureAt(reader, offset) — 8BIM/8B64 по абсолютному offset.

warn_or_throw

Зеркало warnOrThrow(reader, message).

Type Aliases

ReadResult

Результат операций ридера.