authorgravatar for rohlemF@gmail.comRohlem <rohlemF@gmail.com> 2020-12-23 02:39:02+01:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2021-01-11 17:48:18-07:00
logcb205039903868a6273b9f9d65916e943675d540
treebe53c9c8e421fe65bc7756340390ac3705f94382
parent64c5f4979e99b35ef8a2a2c200c095b4d8917328

std.os.windows.GetFinalPathNameByHandle: address non-structural review comments

5 files changed, 80 insertions(+), 87 deletions(-)

lib/std/os/windows.zig+59-58
......@@ -29,7 +29,8 @@ pub const gdi32 = @import("windows/gdi32.zig");
2929pub usingnamespace @import("windows/bits.zig");
3030
3131//version detection
32usingnamespace std.zig.system.windows;
32const version = std.zig.system.windows;
33const WindowsVersion = version.WindowsVersion;
3334
3435pub const self_process_handle = @intToPtr(HANDLE, maxInt(usize));
3536
......@@ -963,42 +964,44 @@ pub fn QueryObjectName(
963964 var full_buffer: [@sizeOf(OBJECT_NAME_INFORMATION) + PATH_MAX_WIDE * 2]u8 align(@alignOf(OBJECT_NAME_INFORMATION)) = undefined;
964965 var info = @ptrCast(*OBJECT_NAME_INFORMATION, &full_buffer);
965966 //buffer size is specified in bytes
966 const full_buffer_length = @intCast(ULONG, @sizeOf(OBJECT_NAME_INFORMATION) + std.math.min(PATH_MAX_WIDE, (out_buffer.len + 1) * 2));
967967 //last argument would return the length required for full_buffer, not exposed here
968 const rc = ntdll.NtQueryObject(handle, .ObjectNameInformation, full_buffer[0..], full_buffer_length, null);
969 return switch (rc) {
970 .SUCCESS => if (@ptrCast(?[*]WCHAR, info.Name.Buffer)) |buffer| blk: {
968 const rc = ntdll.NtQueryObject(handle, .ObjectNameInformation, &full_buffer, full_buffer.len, null);
969 switch (rc) {
970 .SUCCESS => {
971 // info.Name.Buffer from ObQueryNameString is documented to be null (and MaximumLength == 0)
972 // if the object was "unnamed", not sure if this can happen for file handles
973 if (info.Name.MaximumLength == 0) return error.Unexpected;
971974 //resulting string length is specified in bytes
972975 const path_length_unterminated = @divExact(info.Name.Length, 2);
973976 if (out_buffer.len < path_length_unterminated) {
974977 return error.NameTooLong;
975978 }
976 std.mem.copy(WCHAR, out_buffer[0..path_length_unterminated], buffer[0..path_length_unterminated :0]);
977 break :blk out_buffer[0..path_length_unterminated];
978 } else error.Unexpected,
979 .ACCESS_DENIED => error.AccessDenied,
980 .INVALID_HANDLE => error.InvalidHandle,
981 .BUFFER_OVERFLOW, .BUFFER_TOO_SMALL => error.NameTooLong,
979 mem.copy(WCHAR, out_buffer[0..path_length_unterminated], info.Name.Buffer[0..path_length_unterminated]);
980 return out_buffer[0..path_length_unterminated];
981 },
982 .ACCESS_DENIED => return error.AccessDenied,
983 .INVALID_HANDLE => return error.InvalidHandle,
984 .BUFFER_OVERFLOW, .BUFFER_TOO_SMALL => return error.NameTooLong,
982985 //name_buffer.len >= @sizeOf(OBJECT_NAME_INFORMATION) holds statically
983986 .INFO_LENGTH_MISMATCH => unreachable,
984 else => |e| unexpectedStatus(e),
985 };
987 else => |e| return unexpectedStatus(e),
988 }
986989}
987990test "QueryObjectName" {
988991 if (comptime builtin.os.tag != .windows)
989992 return;
990993
991994 //any file will do; canonicalization works on NTFS junctions and symlinks, hardlinks remain separate paths.
992 const file = try std.fs.openSelfExe(.{});
993 defer file.close();
994 //make this large enough for the test runner exe path
995 var out_buffer align(16) = std.mem.zeroes([1 << 10]u16);
995 var tmp = std.testing.tmpDir(.{});
996 defer tmp.cleanup();
997 const handle = tmp.dir.fd;
998 var out_buffer: [PATH_MAX_WIDE]u16 = undefined;
996999
997 var result_path = try QueryObjectName(file.handle, out_buffer[0..]);
1000 var result_path = try QueryObjectName(handle, &out_buffer);
9981001 //insufficient size
999 std.testing.expectError(error.NameTooLong, QueryObjectName(file.handle, out_buffer[0 .. result_path.len - 1]));
1002 std.testing.expectError(error.NameTooLong, QueryObjectName(handle, out_buffer[0 .. result_path.len - 1]));
10001003 //exactly-sufficient size
1001 _ = try QueryObjectName(file.handle, out_buffer[0..result_path.len]);
1004 _ = try QueryObjectName(handle, out_buffer[0..result_path.len]);
10021005}
10031006
10041007pub const GetFinalPathNameByHandleError = error{
......@@ -1030,16 +1033,16 @@ pub fn GetFinalPathNameByHandle(
10301033 fmt: GetFinalPathNameByHandleFormat,
10311034 out_buffer: []u16,
10321035) GetFinalPathNameByHandleError![]u16 {
1033 var path_buffer: [std.math.max(@sizeOf(FILE_NAME_INFORMATION), @sizeOf(OBJECT_NAME_INFORMATION)) + PATH_MAX_WIDE * 2]u8 align(@alignOf(FILE_NAME_INFORMATION)) = undefined;
1036 var path_buffer: [math.max(@sizeOf(FILE_NAME_INFORMATION), @sizeOf(OBJECT_NAME_INFORMATION)) + PATH_MAX_WIDE * 2]u8 align(@alignOf(FILE_NAME_INFORMATION)) = undefined;
10341037 var volume_buffer: [@sizeOf(FILE_NAME_INFORMATION) + MAX_PATH]u8 align(@alignOf(FILE_NAME_INFORMATION)) = undefined; // MAX_PATH bytes should be enough since it's Windows-defined name
10351038
10361039 var file_name_u16: []const u16 = undefined;
10371040 var volume_name_u16: []const u16 = undefined;
1038 if ((comptime (targetVersionIsAtLeast(WindowsVersion.win10_rs4) != true)) //need explicit comptime, because error returns affect return type
1039 and !runtimeVersionIsAtLeast(WindowsVersion.win10_rs4))
1040 {
1041 const final_path = QueryObjectName(hFile, std.mem.bytesAsSlice(u16, path_buffer[0..])) catch |err| return switch (err) {
1042 error.InvalidHandle => error.FileNotFound, //close enough?
1041 if ((comptime (std.builtin.os.version_range.windows.isAtLeast(WindowsVersion.win10_rs4) != true)) and !version.detectRuntimeVersion().isAtLeast(WindowsVersion.win10_rs4)) {
1042 const final_path = QueryObjectName(hFile, mem.bytesAsSlice(u16, &path_buffer)) catch |err| return switch (err) {
1043 // we assume InvalidHandle is close enough to FileNotFound in semantics
1044 // to not further complicate the error set
1045 error.InvalidHandle => error.FileNotFound,
10431046 else => |e| e,
10441047 };
10451048
......@@ -1047,39 +1050,40 @@ pub fn GetFinalPathNameByHandle(
10471050 if (out_buffer.len < final_path.len) {
10481051 return error.NameTooLong;
10491052 }
1050 std.mem.copy(u16, out_buffer[0..], final_path[0..]);
1051 return final_path; //we can directly return the slice we received
1053 mem.copy(u16, out_buffer, final_path);
1054 return out_buffer[0..final_path.len];
10521055 }
10531056
10541057 //otherwise we need to parse the string for volume path for the .Dos logic below to work
10551058 const expected_prefix = std.unicode.utf8ToUtf16LeStringLiteral("\\Device\\");
1056 if (!std.mem.eql(u16, expected_prefix, final_path[0..expected_prefix.len])) {
1057 //TODO find out if this can occur, and if we need to handle it differently
1058 //(i.e. how to determine the end of a volume name)
1059 return error.BadPathName;
1060 }
1061 const index = std.mem.indexOfPos(u16, final_path, expected_prefix.len, &[_]u16{'\\'}) orelse unreachable;
1059
1060 // TODO find out if a path can start with something besides `\Device\<volume name>`,
1061 // and if we need to handle it differently
1062 // (i.e. how to determine the start and end of the volume name in that case)
1063 if (!mem.eql(u16, expected_prefix, final_path[0..expected_prefix.len])) return error.Unexpected;
1064
1065 const index = mem.indexOfPos(u16, final_path, expected_prefix.len, &[_]u16{'\\'}) orelse unreachable;
10621066 volume_name_u16 = final_path[0..index];
10631067 file_name_u16 = final_path[index..];
10641068
10651069 //fallthrough for fmt.volume_name != .Nt
10661070 } else {
10671071 // Get normalized path; doesn't include volume name though.
1068 try QueryInformationFile(hFile, .FileNormalizedNameInformation, path_buffer[0..]);
1069 const file_name = @ptrCast(*const FILE_NAME_INFORMATION, &path_buffer[0]);
1070 file_name_u16 = @ptrCast([*]const u16, &file_name.FileName[0])[0..@divExact(file_name.FileNameLength, 2)];
1072 try QueryInformationFile(hFile, .FileNormalizedNameInformation, &path_buffer);
1073 const file_name = @ptrCast(*const FILE_NAME_INFORMATION, &path_buffer);
1074 file_name_u16 = @ptrCast([*]const u16, &file_name.FileName)[0..@divExact(file_name.FileNameLength, 2)];
10711075
10721076 // Get NT volume name.
1073 try QueryInformationFile(hFile, .FileVolumeNameInformation, volume_buffer[0..]);
1074 const volume_name_info = @ptrCast(*const FILE_NAME_INFORMATION, &volume_buffer[0]);
1075 volume_name_u16 = @ptrCast([*]const u16, &volume_name_info.FileName[0])[0..@divExact(volume_name_info.FileNameLength, 2)];
1077 try QueryInformationFile(hFile, .FileVolumeNameInformation, &volume_buffer);
1078 const volume_name_info = @ptrCast(*const FILE_NAME_INFORMATION, &volume_buffer);
1079 volume_name_u16 = @ptrCast([*]const u16, &volume_name_info.FileName)[0..@divExact(volume_name_info.FileNameLength, 2)];
10761080
10771081 if (fmt.volume_name == .Nt) {
10781082 // Nothing to do, we simply copy the bytes to the user-provided buffer.
10791083 if (out_buffer.len < volume_name_u16.len + file_name_u16.len) return error.NameTooLong;
10801084
1081 std.mem.copy(u16, out_buffer[0..], volume_name_u16);
1082 std.mem.copy(u16, out_buffer[volume_name_u16.len..], file_name_u16);
1085 mem.copy(u16, out_buffer, volume_name_u16);
1086 mem.copy(u16, out_buffer[volume_name_u16.len..], file_name_u16);
10831087
10841088 return out_buffer[0 .. volume_name_u16.len + file_name_u16.len];
10851089 }
......@@ -1124,7 +1128,7 @@ pub fn GetFinalPathNameByHandle(
11241128 input_struct.DeviceNameLength = @intCast(USHORT, volume_name_u16.len * 2);
11251129 @memcpy(input_buf[@sizeOf(MOUNTMGR_MOUNT_POINT)..], @ptrCast([*]const u8, volume_name_u16.ptr), volume_name_u16.len * 2);
11261130
1127 DeviceIoControl(mgmt_handle, IOCTL_MOUNTMGR_QUERY_POINTS, input_buf[0..], output_buf[0..]) catch |err| switch (err) {
1131 DeviceIoControl(mgmt_handle, IOCTL_MOUNTMGR_QUERY_POINTS, &input_buf, &output_buf) catch |err| switch (err) {
11281132 error.AccessDenied => unreachable,
11291133 else => |e| return e,
11301134 };
......@@ -1144,22 +1148,20 @@ pub fn GetFinalPathNameByHandle(
11441148
11451149 // Look for `\DosDevices\` prefix. We don't really care if there are more than one symlinks
11461150 // with traditional DOS drive letters, so pick the first one available.
1147 const prefix_u8 = "\\DosDevices\\";
1148 var prefix_buf_u16: [prefix_u8.len]u16 = undefined;
1149 const prefix_len_u16 = std.unicode.utf8ToUtf16Le(prefix_buf_u16[0..], prefix_u8[0..]) catch unreachable;
1150 const prefix = prefix_buf_u16[0..prefix_len_u16];
1151 var prefix_buf = std.unicode.utf8ToUtf16LeStringLiteral("\\DosDevices\\");
1152 const prefix = prefix_buf[0..prefix_buf.len];
11511153
1152 if (std.mem.startsWith(u16, symlink, prefix)) {
1154 if (mem.startsWith(u16, symlink, prefix)) {
11531155 const drive_letter = symlink[prefix.len..];
11541156
11551157 if (out_buffer.len < drive_letter.len + file_name_u16.len) return error.NameTooLong;
11561158
1157 std.mem.copy(u16, out_buffer[0..], drive_letter);
1158 std.mem.copy(u16, out_buffer[drive_letter.len..], file_name_u16);
1159 mem.copy(u16, out_buffer, drive_letter);
1160 mem.copy(u16, out_buffer[drive_letter.len..], file_name_u16);
11591161 const total_len = drive_letter.len + file_name_u16.len;
11601162
11611163 // Validate that DOS does not contain any spurious nul bytes.
1162 if (std.mem.indexOfScalar(u16, out_buffer[0..total_len], 0)) |_| {
1164 if (mem.indexOfScalar(u16, out_buffer[0..total_len], 0)) |_| {
11631165 return error.BadPathName;
11641166 }
11651167
......@@ -1179,15 +1181,14 @@ test "GetFinalPathNameByHandle" {
11791181 return;
11801182
11811183 //any file will do
1182 const file = try std.fs.openSelfExe(.{});
1183 defer file.close();
1184 const handle = file.handle;
1185 //make this large enough for the test runner exe path
1186 var buffer = std.mem.zeroes([1 << 10]u16);
1184 var tmp = std.testing.tmpDir(.{});
1185 defer tmp.cleanup();
1186 const handle = tmp.dir.fd;
1187 var buffer: [PATH_MAX_WIDE]u16 = undefined;
11871188
11881189 //check with sufficient size
1189 const nt_length = (try GetFinalPathNameByHandle(handle, .{ .volume_name = .Nt }, buffer[0..])).len;
1190 const dos_length = (try GetFinalPathNameByHandle(handle, .{ .volume_name = .Dos }, buffer[0..])).len;
1190 const nt_length = (try GetFinalPathNameByHandle(handle, .{ .volume_name = .Nt }, &buffer)).len;
1191 const dos_length = (try GetFinalPathNameByHandle(handle, .{ .volume_name = .Dos }, &buffer)).len;
11911192
11921193 //check with insufficient size
11931194 std.testing.expectError(error.NameTooLong, GetFinalPathNameByHandle(handle, .{ .volume_name = .Nt }, buffer[0 .. nt_length - 1]));
lib/std/os/windows/bits.zig-1
......@@ -66,7 +66,6 @@ pub const SIZE_T = usize;
6666pub const TCHAR = if (UNICODE) WCHAR else u8;
6767pub const UINT = c_uint;
6868pub const ULONG_PTR = usize;
69pub const PULONG = *ULONG;
7069pub const LONG_PTR = isize;
7170pub const DWORD_PTR = ULONG_PTR;
7271pub const UNICODE = false;
lib/std/os/windows/ntdll.zig+1-1
......@@ -119,5 +119,5 @@ pub extern "NtDll" fn NtQueryObject(
119119 ObjectInformationClass: OBJECT_INFORMATION_CLASS,
120120 ObjectInformation: PVOID,
121121 ObjectInformationLength: ULONG,
122 ReturnLength: ?PULONG,
122 ReturnLength: ?*ULONG,
123123) callconv(WINAPI) NTSTATUS;
lib/std/target.zig+20-11
......@@ -95,7 +95,7 @@ pub const Target = struct {
9595 win7 = 0x06010000,
9696 win8 = 0x06020000,
9797 win8_1 = 0x06030000,
98 win10 = 0x0A000000,
98 win10 = 0x0A000000, //aka win10_th1
9999 win10_th2 = 0x0A000001,
100100 win10_rs1 = 0x0A000002,
101101 win10_rs2 = 0x0A000003,
......@@ -103,26 +103,35 @@ pub const Target = struct {
103103 win10_rs4 = 0x0A000005,
104104 win10_rs5 = 0x0A000006,
105105 win10_19h1 = 0x0A000007,
106 win10_20h1 = 0x0A000008,
106 win10_vb = 0x0A000008, //aka win10_19h2
107 win10_mn = 0x0A000009, //aka win10_20h1
108 win10_fe = 0x0A00000A, //aka win10_20h2
107109 _,
108110
109111 /// Latest Windows version that the Zig Standard Library is aware of
110 pub const latest = WindowsVersion.win10_20h1;
112 pub const latest = WindowsVersion.win10_fe;
111113
112114 /// Compared against build numbers reported by the runtime to distinguish win10 versions,
113115 /// where 0x0A000000 + index corresponds to the WindowsVersion u32 value.
114116 pub const known_win10_build_numbers = [_]u32{
115 10240, //win10
117 10240, //win10 aka win10_th1
116118 10586, //win10_th2
117 14393, //win_rs1
118 15063, //win_rs2
119 16299, //win_rs3
120 17134, //win_rs4
121 17763, //win_rs5
122 18362, //win_19h1
123 19041, //win_20h1
119 14393, //win10_rs1
120 15063, //win10_rs2
121 16299, //win10_rs3
122 17134, //win10_rs4
123 17763, //win10_rs5
124 18362, //win10_19h1
125 18363, //win10_vb aka win10_19h2
126 19041, //win10_mn aka win10_20h1
127 19042, //win10_fe aka win10_20h2
124128 };
125129
130 /// Returns whether the first version `self` is newer (greater) than or equal to the second version `ver`.
131 pub fn isAtLeast(self: WindowsVersion, ver: WindowsVersion) bool {
132 return @enumToInt(self) >= @enumToInt(ver);
133 }
134
126135 pub const Range = struct {
127136 min: WindowsVersion,
128137 max: WindowsVersion,
lib/std/zig/system/windows.zig-16
......@@ -43,19 +43,3 @@ pub fn detectRuntimeVersion() WindowsVersion {
4343
4444 return @intToEnum(WindowsVersion, version);
4545}
46
47/// Returns whether the target os versions are uniformly at least as new as the argument:
48/// true/false if this holds for the entire target range, null if it only holds for some.
49pub fn targetVersionIsAtLeast(requested_version: WindowsVersion) ?bool {
50 const requested = @enumToInt(requested_version);
51 const version_range = std.builtin.os.version_range.windows;
52 const target_min = @enumToInt(version_range.min);
53 const target_max = @enumToInt(version_range.max);
54 return if (target_max < requested) false else if (target_min >= requested) true else null;
55}
56
57/// Returns whether the runtime os version is at least as new as the argument.
58pub fn runtimeVersionIsAtLeast(requested_version: WindowsVersion) bool {
59 return targetVersionIsAtLeast(requested_version) orelse
60 (@enumToInt(detectRuntimeVersion()) >= @enumToInt(requested_version));
61}