Commit 39a98dc426
Changed files (1)
lib
std
lib/std/tar.zig
@@ -48,7 +48,7 @@ pub const Header = struct {
/// Return value may point into Header buffer, or might point into the
/// argument buffer.
/// TODO: check against "../" and other nefarious things
- pub fn fullFileName(header: Header, buffer: *[255]u8) ![]const u8 {
+ pub fn fullFileName(header: Header, buffer: *[std.fs.MAX_PATH_BYTES]u8) ![]const u8 {
const n = name(header);
if (!is_ustar(header))
return n;
@@ -83,6 +83,44 @@ pub const Header = struct {
}
};
+const Buffer = struct {
+ buffer: [512 * 8]u8 = undefined,
+ start: usize = 0,
+ end: usize = 0,
+
+ pub fn readChunk(b: *Buffer, reader: anytype, count: usize) ![]const u8 {
+ b.ensureCapacity(1024);
+
+ const ask = @min(b.buffer.len - b.end, count -| (b.end - b.start));
+ b.end += try reader.readAtLeast(b.buffer[b.end..], ask);
+
+ return b.buffer[b.start..b.end];
+ }
+
+ pub fn advance(b: *Buffer, count: usize) void {
+ b.start += count;
+ assert(b.start <= b.end);
+ }
+
+ pub fn skip(b: *Buffer, reader: anytype, count: usize) !void {
+ if (b.start + count > b.end) {
+ try reader.skipBytes(b.start + count - b.end, .{});
+ b.start = b.end;
+ } else {
+ b.advance(count);
+ }
+ }
+
+ inline fn ensureCapacity(b: *Buffer, count: usize) void {
+ if (b.buffer.len - b.start < count) {
+ const dest_end = b.end - b.start;
+ @memcpy(b.buffer[0..dest_end], b.buffer[b.start..b.end]);
+ b.end = dest_end;
+ b.start = 0;
+ }
+ }
+};
+
pub fn pipeToFileSystem(dir: std.fs.Dir, reader: anytype, options: Options) !void {
switch (options.mode_mode) {
.ignore => {},
@@ -95,30 +133,27 @@ pub fn pipeToFileSystem(dir: std.fs.Dir, reader: anytype, options: Options) !voi
@panic("TODO: unimplemented: tar ModeMode.executable_bit_only");
},
}
- var file_name_buffer: [255]u8 = undefined;
- var buffer: [512 * 8]u8 = undefined;
- var start: usize = 0;
- var end: usize = 0;
+ var file_name_buffer: [std.fs.MAX_PATH_BYTES]u8 = undefined;
+ var file_name_override_len: usize = 0;
+ var buffer: Buffer = .{};
header: while (true) {
- if (buffer.len - start < 1024) {
- const dest_end = end - start;
- @memcpy(buffer[0..dest_end], buffer[start..end]);
- end = dest_end;
- start = 0;
- }
- const ask_header = @min(buffer.len - end, 1024 -| (end - start));
- end += try reader.readAtLeast(buffer[end..], ask_header);
- switch (end - start) {
+ const chunk = try buffer.readChunk(reader, 1024);
+ switch (chunk.len) {
0 => return,
1...511 => return error.UnexpectedEndOfStream,
else => {},
}
- const header: Header = .{ .bytes = buffer[start..][0..512] };
- start += 512;
+ buffer.advance(512);
+
+ const header: Header = .{ .bytes = chunk[0..512] };
const file_size = try header.fileSize();
const rounded_file_size = std.mem.alignForward(u64, file_size, 512);
const pad_len = @as(usize, @intCast(rounded_file_size - file_size));
- const unstripped_file_name = try header.fullFileName(&file_name_buffer);
+ const unstripped_file_name = if (file_name_override_len > 0)
+ file_name_buffer[0..file_name_override_len]
+ else
+ try header.fullFileName(&file_name_buffer);
+ file_name_override_len = 0;
switch (header.fileType()) {
.directory => {
const file_name = try stripComponents(unstripped_file_name, options.strip_components);
@@ -138,36 +173,59 @@ pub fn pipeToFileSystem(dir: std.fs.Dir, reader: anytype, options: Options) !voi
var file_off: usize = 0;
while (true) {
- if (buffer.len - start < 1024) {
- const dest_end = end - start;
- @memcpy(buffer[0..dest_end], buffer[start..end]);
- end = dest_end;
- start = 0;
- }
- // Ask for the rounded up file size + 512 for the next header.
- // TODO: https://github.com/ziglang/zig/issues/14039
- const ask = @as(usize, @intCast(@min(
- buffer.len - end,
- rounded_file_size + 512 - file_off -| (end - start),
- )));
- end += try reader.readAtLeast(buffer[end..], ask);
- if (end - start < ask) return error.UnexpectedEndOfStream;
- // TODO: https://github.com/ziglang/zig/issues/14039
- const slice = buffer[start..@as(usize, @intCast(@min(file_size - file_off + start, end)))];
+ const temp = try buffer.readChunk(reader, @intCast(rounded_file_size + 512 - file_off));
+ if (temp.len == 0) return error.UnexpectedEndOfStream;
+ const slice = temp[0..@as(usize, @intCast(@min(file_size - file_off, temp.len)))];
try file.writeAll(slice);
+
file_off += slice.len;
- start += slice.len;
+ buffer.advance(slice.len);
if (file_off >= file_size) {
- start += pad_len;
- // Guaranteed since we use a buffer divisible by 512.
- assert(start <= end);
+ buffer.advance(pad_len);
continue :header;
}
}
},
- .global_extended_header, .extended_header => {
- if (start + rounded_file_size > end) return error.TarHeadersTooBig;
- start = @as(usize, @intCast(start + rounded_file_size));
+ .extended_header => {
+ if (file_size == 0) {
+ buffer.advance(@intCast(rounded_file_size));
+ continue;
+ }
+
+ const chunk_size: usize = @intCast(rounded_file_size + 512);
+ var data_off: usize = 0;
+ file_name_override_len = while (data_off < file_size) {
+ const slice = try buffer.readChunk(reader, chunk_size - data_off);
+ if (slice.len == 0) return error.UnexpectedEndOfStream;
+ const remaining_size: usize = @intCast(file_size - data_off);
+ const attr_info = try parsePaxAttribute(slice[0..@min(remaining_size, slice.len)], remaining_size);
+
+ if (std.mem.eql(u8, attr_info.key, "path")) {
+ if (attr_info.value_len > file_name_buffer.len) return error.NameTooLong;
+ buffer.advance(attr_info.value_off);
+ data_off += attr_info.value_off;
+ break attr_info.value_len;
+ }
+
+ try buffer.skip(reader, attr_info.size);
+ data_off += attr_info.size;
+ } else 0;
+
+ var i: usize = 0;
+ while (i < file_name_override_len) {
+ const slice = try buffer.readChunk(reader, chunk_size - data_off - i);
+ if (slice.len == 0) return error.UnexpectedEndOfStream;
+ const copy_size: usize = @intCast(@min(file_name_override_len - i, slice.len));
+ @memcpy(file_name_buffer[i .. i + copy_size], slice[0..copy_size]);
+ buffer.advance(copy_size);
+ i += copy_size;
+ }
+
+ try buffer.skip(reader, @intCast(rounded_file_size - data_off - file_name_override_len));
+ continue :header;
+ },
+ .global_extended_header => {
+ buffer.skip(reader, @intCast(rounded_file_size)) catch return error.TarHeadersTooBig;
},
.hard_link => return error.TarUnsupportedFileType,
.symbolic_link => return error.TarUnsupportedFileType,
@@ -196,5 +254,44 @@ test stripComponents {
try expectEqualStrings("c", try stripComponents("a/b/c", 2));
}
+const PaxAttributeInfo = struct {
+ size: usize,
+ key: []const u8,
+ value_off: usize,
+ value_len: usize,
+};
+
+fn parsePaxAttribute(data: []const u8, max_size: usize) !PaxAttributeInfo {
+ const pos_space = std.mem.indexOfScalar(u8, data, ' ') orelse return error.InvalidPaxAttribute;
+ const pos_equals = std.mem.indexOfScalarPos(u8, data, pos_space, '=') orelse return error.InvalidPaxAttribute;
+ const kv_size = try std.fmt.parseInt(usize, data[0..pos_space], 10);
+ if (kv_size > max_size) {
+ return error.InvalidPaxAttribute;
+ }
+ return .{
+ .size = kv_size,
+ .key = data[pos_space + 1 .. pos_equals],
+ .value_off = pos_equals + 1,
+ .value_len = kv_size - pos_equals - 2,
+ };
+}
+
+test parsePaxAttribute {
+ const expectEqual = std.testing.expectEqual;
+ const expectEqualStrings = std.testing.expectEqualStrings;
+ const expectError = std.testing.expectError;
+ const prefix = "1011 path=";
+ const file_name = "0123456789" ** 100;
+ const header = prefix ++ file_name ++ "\n";
+ const attr_info = try parsePaxAttribute(header, 1011);
+ try expectEqual(@as(usize, 1011), attr_info.size);
+ try expectEqualStrings("path", attr_info.key);
+ try expectEqual(prefix.len, attr_info.value_off);
+ try expectEqual(file_name.len, attr_info.value_len);
+ try expectEqual(attr_info, try parsePaxAttribute(header, 1012));
+ try expectError(error.InvalidPaxAttribute, parsePaxAttribute(header, 1010));
+ try expectError(error.InvalidPaxAttribute, parsePaxAttribute("", 0));
+}
+
const std = @import("std.zig");
const assert = std.debug.assert;