Commit c6ef83efe54bd19d7cd5dfadff23678d6af10de9 | zig

author	Dominic <4678790+dweiller@users.noreply.github.com> 2023-02-21 14:31:02+11:00
committer	Dominic <4678790+dweiller@users.noreply.github.com> 2023-02-21 14:53:02+11:00
log	c6ef83efe54bd19d7cd5dfadff23678d6af10de9
tree	f505afd84ad546bc8858877601da95649950dedd
parent	c7c35bf9e61035ead3098d109dc894b285373622

std.compress.zstandard: clean up streaming API

1 files changed, 24 insertions(+), 13 deletions(-)

lib
- std
  - compress
    zstandard.zig

lib/std/compress/zstandard.zig+24-13

...	...	@@ -8,10 +8,14 @@ pub const compressed_block = types.compressed_block;
8	8
9	9	pub const decompress = @import("zstandard/decompress.zig");
10	10
	11	pub const DecompressStreamOptions = struct {
	12	verify_checksum: bool = true,
	13	window_size_max: usize = 1 << 23, // 8MiB default maximum window size,
	14	};
	15
11	16	pub fn DecompressStream(
12	17	comptime ReaderType: type,
13		comptime verify_checksum: bool,
14		comptime window_size_max: usize,
	18	comptime options: DecompressStreamOptions,
15	19	) type {
16	20	return struct {
17	21	const Self = @This();
...	...	@@ -27,7 +31,7 @@ pub fn DecompressStream(
27	31	offset_fse_buffer: []types.compressed_block.Table.Fse,
28	32	literals_buffer: []u8,
29	33	sequence_buffer: []u8,
30		checksum: if (verify_checksum) ?u32 else void,
	34	checksum: if (options.verify_checksum) ?u32 else void,
31	35	current_frame_decompressed_size: usize,
32	36
33	37	pub const Error = ReaderType.Error \|\| error{
...	...	@@ -69,8 +73,8 @@ pub fn DecompressStream(
69	73	const frame_context = context: {
70	74	break :context try decompress.FrameContext.init(
71	75	header,
72		window_size_max,
73		verify_checksum,
	76	options.window_size_max,
	77	options.verify_checksum,
74	78	);
75	79	};
76	80
...	...	@@ -99,10 +103,10 @@ pub fn DecompressStream(
99	103	);
100	104	const buffer = try RingBuffer.init(self.allocator, frame_context.window_size);
101	105
102		const literals_data = try self.allocator.alloc(u8, window_size_max);
	106	const literals_data = try self.allocator.alloc(u8, options.window_size_max);
103	107	errdefer self.allocator.free(literals_data);
104	108
105		const sequence_data = try self.allocator.alloc(u8, window_size_max);
	109	const sequence_data = try self.allocator.alloc(u8, options.window_size_max);
106	110	errdefer self.allocator.free(sequence_data);
107	111
108	112	self.literal_fse_buffer = literal_fse_buffer;
...	...	@@ -116,7 +120,7 @@ pub fn DecompressStream(
116	120	self.decode_state = decode_state;
117	121	self.frame_context = frame_context;
118	122
119		self.checksum = if (verify_checksum) null else {};
	123	self.checksum = if (options.verify_checksum) null else {};
120	124	self.current_frame_decompressed_size = 0;
121	125
122	126	self.state = .InFrame;
...	...	@@ -199,7 +203,7 @@ pub fn DecompressStream(
199	203	if (self.frame_context.has_checksum) {
200	204	const checksum = source_reader.readIntLittle(u32) catch
201	205	return error.MalformedFrame;
202		if (comptime verify_checksum) {
	206	if (comptime options.verify_checksum) {
203	207	if (self.frame_context.hasher_opt) \|*hasher\| {
204	208	if (checksum != decompress.computeChecksum(hasher))
205	209	return error.ChecksumFailure;
...	...	@@ -232,17 +236,24 @@ pub fn DecompressStream(
232	236	};
233	237	}
234	238
	239	pub fn decompressStreamOptions(
	240	allocator: Allocator,
	241	reader: anytype,
	242	comptime options: DecompressStreamOptions,
	243	) DecompressStream(@TypeOf(reader, options)) {
	244	return DecompressStream(@TypeOf(reader), options).init(allocator, reader);
	245	}
	246
235	247	pub fn decompressStream(
236	248	allocator: Allocator,
237	249	reader: anytype,
238		comptime window_size_max: usize,
239		) DecompressStream(@TypeOf(reader), true, window_size_max) {
240		return DecompressStream(@TypeOf(reader), true, 8 * (1 << 20)).init(allocator, reader);
	250	) DecompressStream(@TypeOf(reader), .{}) {
	251	return DecompressStream(@TypeOf(reader), .{}).init(allocator, reader);
241	252	}
242	253
243	254	fn testDecompress(data: []const u8) ![]u8 {
244	255	var in_stream = std.io.fixedBufferStream(data);
245		var zstd_stream = decompressStream(std.testing.allocator, in_stream.reader(), 1 << 23);
	256	var zstd_stream = decompressStream(std.testing.allocator, in_stream.reader());
246	257	defer zstd_stream.deinit();
247	258	const result = zstd_stream.reader().readAllAlloc(std.testing.allocator, std.math.maxInt(usize));
248	259	return result;