parseToken

This commit is contained in:
jaina heartles 2022-12-19 04:31:18 -08:00
parent e3f90f22ef
commit 4c661672c2

View file

@ -265,3 +265,87 @@ fn parseEncoding(encoding: ?[]const u8) !Encoding {
if (std.mem.eql(u8, encoding.?, "chunked")) return .chunked;
return error.UnsupportedMediaType;
}
fn isTokenChar(ch: u8) bool {
switch (ch) {
'"', '(', ')', '/', ':', ';', '<', '=', '>', '?', '@', '[', '\\', ']', '{', '}' => return false,
'!', '#', '$', '%', '&', '\'', '*', '+', '-', '.', '^', '_', '`', '|', '~' => return true,
else => return std.ascii.isAlphanumeric(ch),
}
}
fn parseToken(alloc: std.mem.Allocator, peek_stream: anytype) ![]const u8 {
var data = std.ArrayList(u8).init(alloc);
errdefer data.deinit();
const reader = peek_stream.reader();
while (reader.readByte()) |ch| {
if (!isTokenChar(ch)) {
try peek_stream.putBackByte(ch);
break;
}
try data.append(ch);
} else |err| if (err != error.EndOfStream) return err;
return data.toOwnedSlice();
}
test "parseToken" {
const testCase = struct {
fn func(data: []const u8, err: ?anyerror, expected: anyerror![]const u8, remaining: []const u8) !void {
var fbs = std.io.fixedBufferStream(data);
var stream = errorReader(err orelse error.EndOfStream, fbs.reader());
var peeker = std.io.peekStream(1, stream.reader());
const result = parseToken(std.testing.allocator, &peeker);
defer if (result) |v| std.testing.allocator.free(v) else |_| {};
if (expected) |val|
try std.testing.expectEqualStrings(val, try result)
else |expected_err|
try std.testing.expectError(expected_err, result);
try std.testing.expect(try peeker.reader().isBytes(remaining));
try std.testing.expectError(err orelse error.EndOfStream, peeker.reader().readByte());
}
}.func;
try testCase("abcdefg", null, "abcdefg", "");
try testCase("abc defg", null, "abc", " defg");
try testCase("abc;defg", null, "abc", ";defg");
try testCase("abc%defg$; ", null, "abc%defg$", "; ");
try testCase(" ", null, "", " ");
try testCase(";", null, "", ";");
try testCase("abcdefg", error.ClosedPipe, error.ClosedPipe, "");
}
fn ErrorReader(comptime E: type, comptime ReaderType: type) type {
return struct {
inner_reader: ReaderType,
err: E,
pub const Error = ReaderType.Error || E;
pub const Reader = std.io.Reader(*@This(), Error, read);
pub fn read(self: *@This(), dest: []u8) Error!usize {
const count = try self.inner_reader.readAll(dest);
if (count == 0) return self.err;
return dest.len;
}
pub fn reader(self: *@This()) Reader {
return .{ .context = self };
}
};
}
/// Returns the given error after the underlying stream is finished
fn errorReader(err: anytype, reader: anytype) ErrorReader(@TypeOf(err), @TypeOf(reader)) {
return .{
.inner_reader = reader,
.err = err,
};
}