const std = @import("../std.zig");
const builtin = @import("builtin");
const io = std.io;
pub const StreamSource = union(enum) {
const has_file = (builtin.os.tag != .freestanding);
buffer: io.FixedBufferStream([]u8),
const_buffer: io.FixedBufferStream([]const u8),
file: if (has_file) std.fs.File else void,
pub const ReadError = io.FixedBufferStream([]u8).ReadError || (if (has_file) std.fs.File.ReadError else error{});
pub const WriteError = error{AccessDenied} || io.FixedBufferStream([]u8).WriteError || (if (has_file) std.fs.File.WriteError else error{});
pub const SeekError = io.FixedBufferStream([]u8).SeekError || (if (has_file) std.fs.File.SeekError else error{});
pub const GetSeekPosError = io.FixedBufferStream([]u8).GetSeekPosError || (if (has_file) std.fs.File.GetSeekPosError else error{});
pub const Reader = io.Reader(*StreamSource, ReadError, read);
pub const Writer = io.Writer(*StreamSource, WriteError, write);
pub const SeekableStream = io.SeekableStream(
*StreamSource,
SeekError,
GetSeekPosError,
seekTo,
seekBy,
getPos,
getEndPos,
);
pub fn read(self: *StreamSource, dest: []u8) ReadError!usize {
switch (self.*) {
.buffer => |*x| return x.read(dest),
.const_buffer => |*x| return x.read(dest),
.file => |x| if (!has_file) unreachable else return x.read(dest),
}
}
pub fn write(self: *StreamSource, bytes: []const u8) WriteError!usize {
switch (self.*) {
.buffer => |*x| return x.write(bytes),
.const_buffer => return error.AccessDenied,
.file => |x| if (!has_file) unreachable else return x.write(bytes),
}
}
pub fn seekTo(self: *StreamSource, pos: u64) SeekError!void {
switch (self.*) {
.buffer => |*x| return x.seekTo(pos),
.const_buffer => |*x| return x.seekTo(pos),
.file => |x| if (!has_file) unreachable else return x.seekTo(pos),
}
}
pub fn seekBy(self: *StreamSource, amt: i64) SeekError!void {
switch (self.*) {
.buffer => |*x| return x.seekBy(amt),
.const_buffer => |*x| return x.seekBy(amt),
.file => |x| if (!has_file) unreachable else return x.seekBy(amt),
}
}
pub fn getEndPos(self: *StreamSource) GetSeekPosError!u64 {
switch (self.*) {
.buffer => |*x| return x.getEndPos(),
.const_buffer => |*x| return x.getEndPos(),
.file => |x| if (!has_file) unreachable else return x.getEndPos(),
}
}
pub fn getPos(self: *StreamSource) GetSeekPosError!u64 {
switch (self.*) {
.buffer => |*x| return x.getPos(),
.const_buffer => |*x| return x.getPos(),
.file => |x| if (!has_file) unreachable else return x.getPos(),
}
}
pub fn reader(self: *StreamSource) Reader {
return .{ .context = self };
}
pub fn writer(self: *StreamSource) Writer {
return .{ .context = self };
}
pub fn seekableStream(self: *StreamSource) SeekableStream {
return .{ .context = self };
}
};
test "StreamSource (refs)" {
std.testing.refAllDecls(StreamSource);
}
test "StreamSource (mutable buffer)" {
var buffer: [64]u8 = undefined;
var source = StreamSource{ .buffer = std.io.fixedBufferStream(&buffer) };
var writer = source.writer();
try writer.writeAll("Hello, World!");
try std.testing.expectEqualStrings("Hello, World!", source.buffer.getWritten());
}
test "StreamSource (const buffer)" {
const buffer: [64]u8 = "Hello, World!".* ++ ([1]u8{0xAA} ** 51);
var source = StreamSource{ .const_buffer = std.io.fixedBufferStream(&buffer) };
var reader = source.reader();
var dst_buffer: [13]u8 = undefined;
try reader.readNoEof(&dst_buffer);
try std.testing.expectEqualStrings("Hello, World!", &dst_buffer);
}