// Copyright 2020 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
library zx;

type stream_seek_origin = strict enum : uint32 {
    START = 0;
    CURRENT = 1;
    END = 2;
};

@transport("Syscall")
protocol stream {
    /// Create a stream from a VMO.
    stream_create(resource struct {
        options uint32;
        vmo handle:VMO;
        seek off;
    }) -> (resource struct {
        status status;
        out_stream handle:STREAM;
    });

    /// Write data to a stream at the current seek offset.
    /// Rights: handle must be of type ZX_OBJ_TYPE_STREAM and have ZX_RIGHT_WRITE.
    @blocking
    stream_writev(resource struct {
        handle handle:STREAM;
        options uint32;
        vector vector_iovec;
    }) -> (struct {
        status status;
        actual optional_usize;
    });

    /// Write data to a stream at the given offset.
    /// Rights: handle must be of type ZX_OBJ_TYPE_STREAM and have ZX_RIGHT_WRITE.
    @blocking
    stream_writev_at(resource struct {
        handle handle:STREAM;
        options uint32;
        offset off;
        vector vector_iovec;
    }) -> (struct {
        status status;
        actual optional_usize;
    });

    /// Read data from a stream at the current seek offset.
    /// Rights: handle must be of type ZX_OBJ_TYPE_STREAM and have ZX_RIGHT_READ.
    @blocking
    stream_readv(resource struct {
        handle handle:STREAM;
        options uint32;
    }) -> (struct {
        status status;
        vector vector_iovec;
        actual optional_usize;
    });

    /// Read data from a stream at the given offset.
    /// Rights: handle must be of type ZX_OBJ_TYPE_STREAM and have ZX_RIGHT_READ.
    @blocking
    stream_readv_at(resource struct {
        handle handle:STREAM;
        options uint32;
        offset off;
    }) -> (struct {
        status status;
        vector vector_iovec;
        actual optional_usize;
    });

    /// Modify the seek offset.
    /// Rights: handle must be of type ZX_OBJ_TYPE_STREAM and have ZX_RIGHT_READ or have ZX_RIGHT_WRITE.
    stream_seek(resource struct {
        handle handle:STREAM;
        whence stream_seek_origin;
        offset int64;
    }) -> (struct {
        status status;
        out_seek optional_off;
    });
};