authorgravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2020-03-01 13:53:13-05:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2020-03-01 13:53:13-05:00
log3c1432701129bacf95b944f0f86af2d96ae72c69
treed05e7ddf19d709975f432e60f5a2321309078517
parentb99c6d56da3d2db995c268fb07f48548ea6d1148
parentef3d761da545a3a72928ed0e0ba3b749a4cb74d8
signaturelock-open Commit is signed but in an unrecognized format.

Merge branch 'daurnimator-fmt-sentinel-pointers'

closes #3972

11 files changed, 171 insertions(+), 27 deletions(-)

lib/std/builtin.zig+2
......@@ -185,6 +185,7 @@ pub const TypeInfo = union(enum) {
185185 child: type,
186186 is_allowzero: bool,
187187
188 /// This field is an optional type.
188189 /// The type of the sentinel is the element type of the pointer, which is
189190 /// the value of the `child` field in this struct. However there is no way
190191 /// to refer to that type here, so we use `var`.
......@@ -206,6 +207,7 @@ pub const TypeInfo = union(enum) {
206207 len: comptime_int,
207208 child: type,
208209
210 /// This field is an optional type.
209211 /// The type of the sentinel is the element type of the array, which is
210212 /// the value of the `child` field in this struct. However there is no way
211213 /// to refer to that type here, so we use `var`.
lib/std/cstr.zig+1-1
......@@ -28,7 +28,7 @@ test "cstr fns" {
2828
2929fn testCStrFnsImpl() void {
3030 testing.expect(cmp("aoeu", "aoez") == -1);
31 testing.expect(mem.len(u8, "123456789") == 9);
31 testing.expect(mem.len("123456789") == 9);
3232}
3333
3434/// Returns a mutable, null-terminated slice with the same length as `slice`.
lib/std/fmt.zig+4-2
......@@ -441,10 +441,12 @@ pub fn formatType(
441441 else => return format(context, Errors, output, "{}@{x}", .{ @typeName(T.Child), @ptrToInt(value) }),
442442 },
443443 .Many, .C => {
444 if (ptr_info.sentinel) |sentinel| {
445 return formatType(mem.span(value), fmt, options, context, Errors, output, max_depth);
446 }
444447 if (ptr_info.child == u8) {
445448 if (fmt.len > 0 and fmt[0] == 's') {
446 const len = mem.len(u8, value);
447 return formatText(value[0..len], fmt, options, context, Errors, output);
449 return formatText(mem.span(value), fmt, options, context, Errors, output);
448450 }
449451 }
450452 return format(context, Errors, output, "{}@{x}", .{ @typeName(T.Child), @ptrToInt(value) });
lib/std/mem.zig+126-12
......@@ -333,8 +333,20 @@ pub fn zeroes(comptime T: type) T {
333333 }
334334 return array;
335335 },
336 .Vector, .ErrorUnion, .ErrorSet, .Union, .Fn, .BoundFn, .Type, .NoReturn, .Undefined, .Opaque, .Frame, .AnyFrame, => {
337 @compileError("Can't set a "++ @typeName(T) ++" to zero.");
336 .Vector,
337 .ErrorUnion,
338 .ErrorSet,
339 .Union,
340 .Fn,
341 .BoundFn,
342 .Type,
343 .NoReturn,
344 .Undefined,
345 .Opaque,
346 .Frame,
347 .AnyFrame,
348 => {
349 @compileError("Can't set a " ++ @typeName(T) ++ " to zero.");
338350 },
339351 }
340352}
......@@ -470,18 +482,115 @@ pub fn eql(comptime T: type, a: []const T, b: []const T) bool {
470482 return true;
471483}
472484
473pub fn len(comptime T: type, ptr: [*:0]const T) usize {
474 var count: usize = 0;
475 while (ptr[count] != 0) : (count += 1) {}
476 return count;
477}
478
485/// Deprecated. Use `span`.
479486pub fn toSliceConst(comptime T: type, ptr: [*:0]const T) [:0]const T {
480 return ptr[0..len(T, ptr) :0];
487 return ptr[0..len(ptr) :0];
481488}
482489
490/// Deprecated. Use `span`.
483491pub fn toSlice(comptime T: type, ptr: [*:0]T) [:0]T {
484 return ptr[0..len(T, ptr) :0];
492 return ptr[0..len(ptr) :0];
493}
494
495/// Takes a pointer to an array, a sentinel-terminated pointer, or a slice, and
496/// returns a slice. If there is a sentinel on the input type, there will be a
497/// sentinel on the output type. The constness of the output type matches
498/// the constness of the input type. `[*c]` pointers are assumed to be 0-terminated,
499/// and assumed to not allow null.
500pub fn Span(comptime T: type) type {
501 var ptr_info = @typeInfo(T).Pointer;
502 switch (ptr_info.size) {
503 .One => switch (@typeInfo(ptr_info.child)) {
504 .Array => |info| {
505 ptr_info.child = info.child;
506 ptr_info.sentinel = info.sentinel;
507 },
508 else => @compileError("invalid type given to std.mem.Span"),
509 },
510 .C => {
511 ptr_info.sentinel = 0;
512 ptr_info.is_allowzero = false;
513 },
514 .Many, .Slice => {},
515 }
516 ptr_info.size = .Slice;
517 return @Type(std.builtin.TypeInfo{ .Pointer = ptr_info });
518}
519
520test "Span" {
521 testing.expect(Span(*[5]u16) == []u16);
522 testing.expect(Span(*const [5]u16) == []const u16);
523 testing.expect(Span([]u16) == []u16);
524 testing.expect(Span([]const u8) == []const u8);
525 testing.expect(Span([:1]u16) == [:1]u16);
526 testing.expect(Span([:1]const u8) == [:1]const u8);
527 testing.expect(Span([*:1]u16) == [:1]u16);
528 testing.expect(Span([*:1]const u8) == [:1]const u8);
529 testing.expect(Span([*c]u16) == [:0]u16);
530 testing.expect(Span([*c]const u8) == [:0]const u8);
531}
532
533/// Takes a pointer to an array, a sentinel-terminated pointer, or a slice, and
534/// returns a slice. If there is a sentinel on the input type, there will be a
535/// sentinel on the output type. The constness of the output type matches
536/// the constness of the input type.
537pub fn span(ptr: var) Span(@TypeOf(ptr)) {
538 const Result = Span(@TypeOf(ptr));
539 const l = len(ptr);
540 if (@typeInfo(Result).Pointer.sentinel) |s| {
541 return ptr[0..l :s];
542 } else {
543 return ptr[0..l];
544 }
545}
546
547test "span" {
548 var array: [5]u16 = [_]u16{ 1, 2, 3, 4, 5 };
549 const ptr = array[0..2 :3].ptr;
550 testing.expect(eql(u16, span(ptr), &[_]u16{ 1, 2 }));
551 testing.expect(eql(u16, span(&array), &[_]u16{ 1, 2, 3, 4, 5 }));
552}
553
554/// Takes a pointer to an array, an array, a sentinel-terminated pointer,
555/// or a slice, and returns the length.
556pub fn len(ptr: var) usize {
557 return switch (@typeInfo(@TypeOf(ptr))) {
558 .Array => |info| info.len,
559 .Pointer => |info| switch (info.size) {
560 .One => switch (@typeInfo(info.child)) {
561 .Array => |x| x.len,
562 else => @compileError("invalid type given to std.mem.length"),
563 },
564 .Many => if (info.sentinel) |sentinel|
565 indexOfSentinel(info.child, sentinel, ptr)
566 else
567 @compileError("length of pointer with no sentinel"),
568 .C => indexOfSentinel(info.child, 0, ptr),
569 .Slice => ptr.len,
570 },
571 else => @compileError("invalid type given to std.mem.length"),
572 };
573}
574
575test "len" {
576 testing.expect(len("aoeu") == 4);
577
578 {
579 var array: [5]u16 = [_]u16{ 1, 2, 3, 4, 5 };
580 testing.expect(len(&array) == 5);
581 testing.expect(len(array[0..3]) == 3);
582 array[2] = 0;
583 const ptr = array[0..2 :0].ptr;
584 testing.expect(len(ptr) == 2);
585 }
586}
587
588pub fn indexOfSentinel(comptime Elem: type, comptime sentinel: Elem, ptr: [*:sentinel]const Elem) usize {
589 var i: usize = 0;
590 while (ptr[i] != sentinel) {
591 i += 1;
592 }
593 return i;
485594}
486595
487596/// Returns true if all elements in a slice are equal to the scalar value provided
......@@ -1753,8 +1862,13 @@ fn SubArrayPtrReturnType(comptime T: type, comptime length: usize) type {
17531862 return *[length]meta.Child(meta.Child(T));
17541863}
17551864
1756///Given a pointer to an array, returns a pointer to a portion of that array, preserving constness.
1757pub fn subArrayPtr(ptr: var, comptime start: usize, comptime length: usize) SubArrayPtrReturnType(@TypeOf(ptr), length) {
1865/// Given a pointer to an array, returns a pointer to a portion of that array, preserving constness.
1866/// TODO this will be obsoleted by https://github.com/ziglang/zig/issues/863
1867pub fn subArrayPtr(
1868 ptr: var,
1869 comptime start: usize,
1870 comptime length: usize,
1871) SubArrayPtrReturnType(@TypeOf(ptr), length) {
17581872 assert(start + length <= ptr.*.len);
17591873
17601874 const ReturnType = SubArrayPtrReturnType(@TypeOf(ptr), length);
lib/std/meta.zig+26
......@@ -115,6 +115,32 @@ test "std.meta.Child" {
115115 testing.expect(Child(?u8) == u8);
116116}
117117
118/// Given a type with a sentinel e.g. `[:0]u8`, returns the sentinel
119pub fn Sentinel(comptime T: type) Child(T) {
120 // comptime asserts that ptr has a sentinel
121 switch (@typeInfo(T)) {
122 .Array => |arrayInfo| {
123 return comptime arrayInfo.sentinel.?;
124 },
125 .Pointer => |ptrInfo| {
126 switch (ptrInfo.size) {
127 .Many, .Slice => {
128 return comptime ptrInfo.sentinel.?;
129 },
130 else => {},
131 }
132 },
133 else => {},
134 }
135 @compileError("not a sentinel type, found '" ++ @typeName(T) ++ "'");
136}
137
138test "std.meta.Sentinel" {
139 testing.expectEqual(@as(u8, 0), Sentinel([:0]u8));
140 testing.expectEqual(@as(u8, 0), Sentinel([*:0]u8));
141 testing.expectEqual(@as(u8, 0), Sentinel([5:0]u8));
142}
143
118144pub fn containerLayout(comptime T: type) TypeInfo.ContainerLayout {
119145 return switch (@typeInfo(T)) {
120146 .Struct => |info| info.layout,
lib/std/net.zig+1-1
......@@ -352,7 +352,7 @@ pub const Address = extern union {
352352 unreachable;
353353 }
354354
355 const path_len = std.mem.len(u8, @ptrCast([*:0]const u8, &self.un.path));
355 const path_len = std.mem.len(@ptrCast([*:0]const u8, &self.un.path));
356356 return @intCast(os.socklen_t, @sizeOf(os.sockaddr_un) - self.un.path.len + path_len);
357357 },
358358 else => unreachable,
lib/std/os.zig+1-1
......@@ -1095,7 +1095,7 @@ pub fn createNullDelimitedEnvMap(allocator: *mem.Allocator, env_map: *const std.
10951095
10961096pub fn freeNullDelimitedEnvMap(allocator: *mem.Allocator, envp_buf: []?[*:0]u8) void {
10971097 for (envp_buf) |env| {
1098 const env_buf = if (env) |ptr| ptr[0 .. mem.len(u8, ptr) + 1] else break;
1098 const env_buf = if (env) |ptr| ptr[0 .. mem.len(ptr) + 1] else break;
10991099 allocator.free(env_buf);
11001100 }
11011101 allocator.free(envp_buf);
lib/std/special/c.zig+1-1
......@@ -47,7 +47,7 @@ fn strcmp(s1: [*:0]const u8, s2: [*:0]const u8) callconv(.C) c_int {
4747}
4848
4949fn strlen(s: [*:0]const u8) callconv(.C) usize {
50 return std.mem.len(u8, s);
50 return std.mem.len(s);
5151}
5252
5353fn strncmp(_l: [*:0]const u8, _r: [*:0]const u8, _n: usize) callconv(.C) c_int {
src-self-hosted/main.zig+7-7
......@@ -792,7 +792,7 @@ async fn fmtPath(fmt: *Fmt, file_path_ref: []const u8, check_mode: bool) FmtErro
792792}
793793
794794fn cmdVersion(allocator: *Allocator, args: []const []const u8) !void {
795 try stdout.print("{}\n", .{std.mem.toSliceConst(u8, c.ZIG_VERSION_STRING)});
795 try stdout.print("{}\n", .{c.ZIG_VERSION_STRING});
796796}
797797
798798fn cmdHelp(allocator: *Allocator, args: []const []const u8) !void {
......@@ -863,12 +863,12 @@ fn cmdInternalBuildInfo(allocator: *Allocator, args: []const []const u8) !void {
863863 \\ZIG_DIA_GUIDS_LIB {}
864864 \\
865865 , .{
866 std.mem.toSliceConst(u8, c.ZIG_CMAKE_BINARY_DIR),
867 std.mem.toSliceConst(u8, c.ZIG_CXX_COMPILER),
868 std.mem.toSliceConst(u8, c.ZIG_LLD_INCLUDE_PATH),
869 std.mem.toSliceConst(u8, c.ZIG_LLD_LIBRARIES),
870 std.mem.toSliceConst(u8, c.ZIG_LLVM_CONFIG_EXE),
871 std.mem.toSliceConst(u8, c.ZIG_DIA_GUIDS_LIB),
866 c.ZIG_CMAKE_BINARY_DIR,
867 c.ZIG_CXX_COMPILER,
868 c.ZIG_LLD_INCLUDE_PATH,
869 c.ZIG_LLD_LIBRARIES,
870 c.ZIG_LLVM_CONFIG_EXE,
871 c.ZIG_DIA_GUIDS_LIB,
872872 });
873873}
874874
src-self-hosted/translate_c.zig+1-1
......@@ -4849,7 +4849,7 @@ fn transPreprocessorEntities(c: *Context, unit: *ZigClangASTUnit) Error!void {
48494849 }
48504850
48514851 const begin_c = ZigClangSourceManager_getCharacterData(c.source_manager, begin_loc);
4852 const slice = begin_c[0..mem.len(u8, begin_c)];
4852 const slice = begin_c[0..mem.len(begin_c)];
48534853
48544854 tok_list.shrink(0);
48554855 var tokenizer = std.c.Tokenizer{
test/stage1/behavior/misc.zig+1-1
......@@ -335,7 +335,7 @@ test "string concatenation" {
335335 comptime expect(@TypeOf(a) == *const [12:0]u8);
336336 comptime expect(@TypeOf(b) == *const [12:0]u8);
337337
338 const len = mem.len(u8, b);
338 const len = mem.len(b);
339339 const len_with_null = len + 1;
340340 {
341341 var i: u32 = 0;