diff --git a/lib/std/fs/File.zig b/lib/std/fs/File.zig index 2453370c91..2972c86722 100644 --- a/lib/std/fs/File.zig +++ b/lib/std/fs/File.zig @@ -1648,29 +1648,28 @@ pub const Writer = struct { }; } - pub fn drain(io_writer: *std.io.Writer, data: []const []const u8, splat: usize) std.io.Writer.Error!usize { - const w: *Writer = @fieldParentPtr("interface", io_writer); + pub fn drain(io_w: *std.io.Writer, data: []const []const u8, splat: usize) std.io.Writer.Error!usize { + const w: *Writer = @fieldParentPtr("interface", io_w); const handle = w.file.handle; - const buffered = io_writer.buffered(); - var splat_buffer: [256]u8 = undefined; + const buffered = io_w.buffered(); if (is_windows) { var i: usize = 0; while (i < buffered.len) { const n = windows.WriteFile(handle, buffered[i..], null) catch |err| { w.err = err; w.pos += i; - _ = io_writer.consume(i); + _ = io_w.consume(i); return error.WriteFailed; }; i += n; if (data.len > 0 and buffered.len - i < n) { w.pos += i; - return io_writer.consume(i); + return io_w.consume(i); } } if (i != 0 or data.len == 0 or (data.len == 1 and splat == 0)) { w.pos += i; - return io_writer.consume(i); + return io_w.consume(i); } const n = windows.WriteFile(handle, data[0], null) catch |err| { w.err = err; @@ -1679,19 +1678,6 @@ pub const Writer = struct { w.pos += n; return n; } - if (data.len == 0) { - var i: usize = 0; - while (i < buffered.len) { - i += std.posix.write(handle, buffered) catch |err| { - w.err = err; - w.pos += i; - _ = io_writer.consume(i); - return error.WriteFailed; - }; - } - w.pos += i; - return io_writer.consumeAll(); - } var iovecs: [max_buffers_len]std.posix.iovec_const = undefined; var len: usize = 0; if (buffered.len > 0) { @@ -1700,30 +1686,43 @@ pub const Writer = struct { } for (data) |d| { if (d.len == 0) continue; - if (iovecs.len - len == 0) break; iovecs[len] = .{ .base = d.ptr, .len = d.len }; len += 1; + if (iovecs.len - len == 0) break; } + if (len == 0) return 0; + const pattern = data[data.len - 1]; switch (splat) { - 0 => if (data[data.len - 1].len != 0) { + 0 => if (iovecs[len - 1].base == pattern.ptr) { len -= 1; }, 1 => {}, - else => switch (data[data.len - 1].len) { + else => switch (pattern.len) { 0 => {}, - 1 => { + 1 => memset: { + // Replace the 1-byte buffer with a bigger one. + if (iovecs[len - 1].base == pattern.ptr) len -= 1; + if (iovecs.len - len == 0) break :memset; + const splat_buffer_candidate = io_w.buffer[io_w.end..]; + var backup_buffer: [64]u8 = undefined; + const splat_buffer = if (splat_buffer_candidate.len >= backup_buffer.len) + splat_buffer_candidate + else + &backup_buffer; const memset_len = @min(splat_buffer.len, splat); const buf = splat_buffer[0..memset_len]; - @memset(buf, data[data.len - 1][0]); - iovecs[len - 1] = .{ .base = buf.ptr, .len = buf.len }; + @memset(buf, pattern[0]); + iovecs[len] = .{ .base = buf.ptr, .len = buf.len }; + len += 1; var remaining_splat = splat - buf.len; - while (remaining_splat > splat_buffer.len and len < iovecs.len) { - iovecs[len] = .{ .base = &splat_buffer, .len = splat_buffer.len }; - remaining_splat -= splat_buffer.len; + while (remaining_splat > splat_buffer.len and iovecs.len - len != 0) { + assert(buf.len == splat_buffer.len); + iovecs[len] = .{ .base = splat_buffer.ptr, .len = splat_buffer.len }; len += 1; + remaining_splat -= splat_buffer.len; } - if (remaining_splat > 0 and len < iovecs.len) { - iovecs[len] = .{ .base = &splat_buffer, .len = remaining_splat }; + if (remaining_splat > 0 and iovecs.len - len != 0) { + iovecs[len] = .{ .base = splat_buffer.ptr, .len = remaining_splat }; len += 1; } return std.posix.writev(handle, iovecs[0..len]) catch |err| { @@ -1733,7 +1732,7 @@ pub const Writer = struct { }, else => for (0..splat - 1) |_| { if (iovecs.len - len == 0) break; - iovecs[len] = .{ .base = data[data.len - 1].ptr, .len = data[data.len - 1].len }; + iovecs[len] = .{ .base = pattern.ptr, .len = pattern.len }; len += 1; }, }, @@ -1743,15 +1742,15 @@ pub const Writer = struct { return error.WriteFailed; }; w.pos += n; - return io_writer.consume(n); + return io_w.consume(n); } pub fn sendFile( - io_writer: *std.io.Writer, + io_w: *std.io.Writer, file_reader: *Reader, limit: std.io.Limit, ) std.io.Writer.FileError!usize { - const w: *Writer = @fieldParentPtr("interface", io_writer); + const w: *Writer = @fieldParentPtr("interface", io_w); const out_fd = w.file.handle; const in_fd = file_reader.file.handle; // TODO try using copy_file_range on FreeBSD @@ -1762,7 +1761,7 @@ pub const Writer = struct { if (w.sendfile_err != null) break :sf; // Linux sendfile does not support headers. const buffered = limit.slice(file_reader.interface.buffer); - if (io_writer.end != 0 or buffered.len != 0) return drain(io_writer, &.{buffered}, 1); + if (io_w.end != 0 or buffered.len != 0) return drain(io_w, &.{buffered}, 1); const max_count = 0x7ffff000; // Avoid EINVAL. var off: std.os.linux.off_t = undefined; const off_ptr: ?*std.os.linux.off_t, const count: usize = switch (file_reader.mode) { @@ -1813,7 +1812,7 @@ pub const Writer = struct { if (copy_file_range_fn) |copy_file_range| cfr: { if (w.copy_file_range_err != null) break :cfr; const buffered = limit.slice(file_reader.interface.buffer); - if (io_writer.end != 0 or buffered.len != 0) return drain(io_writer, &.{buffered}, 1); + if (io_w.end != 0 or buffered.len != 0) return drain(io_w, &.{buffered}, 1); var off_in: i64 = undefined; var off_out: i64 = undefined; const off_in_ptr: ?*i64 = switch (file_reader.mode) {