std.tz: update to new Reader API

This commit is contained in:
Andrew Kelley 2025-08-26 23:44:25 -07:00
parent 9860dd475a
commit e9a271cba3

View file

@ -1,6 +1,9 @@
const std = @import("std.zig");
const builtin = @import("builtin");
const std = @import("std.zig");
const Reader = std.Io.Reader;
const Allocator = std.mem.Allocator;
pub const Transition = struct {
ts: i64,
timetype: *Timetype,
@ -34,7 +37,7 @@ pub const Leapsecond = struct {
};
pub const Tz = struct {
allocator: std.mem.Allocator,
allocator: Allocator,
transitions: []const Transition,
timetypes: []const Timetype,
leapseconds: []const Leapsecond,
@ -54,8 +57,8 @@ pub const Tz = struct {
},
};
pub fn parse(allocator: std.mem.Allocator, reader: anytype) !Tz {
var legacy_header = try reader.readStruct(Header);
pub fn parse(allocator: Allocator, reader: *Reader) !Tz {
var legacy_header = try reader.takeStruct(Header, .little);
if (!std.mem.eql(u8, &legacy_header.magic, "TZif")) return error.BadHeader;
if (legacy_header.version != 0 and legacy_header.version != '2' and legacy_header.version != '3') return error.BadVersion;
@ -68,9 +71,9 @@ pub const Tz = struct {
} else {
// If the format is modern, just skip over the legacy data
const skipv = legacy_header.counts.timecnt * 5 + legacy_header.counts.typecnt * 6 + legacy_header.counts.charcnt + legacy_header.counts.leapcnt * 8 + legacy_header.counts.isstdcnt + legacy_header.counts.isutcnt;
try reader.skipBytes(skipv, .{});
try reader.discardAll(skipv);
var header = try reader.readStruct(Header);
var header = try reader.takeStruct(Header, .little);
if (!std.mem.eql(u8, &header.magic, "TZif")) return error.BadHeader;
if (header.version != '2' and header.version != '3') return error.BadVersion;
if (builtin.target.cpu.arch.endian() != std.builtin.Endian.big) {
@ -81,7 +84,7 @@ pub const Tz = struct {
}
}
fn parseBlock(allocator: std.mem.Allocator, reader: anytype, header: Header, legacy: bool) !Tz {
fn parseBlock(allocator: Allocator, reader: *Reader, header: Header, legacy: bool) !Tz {
if (header.counts.isstdcnt != 0 and header.counts.isstdcnt != header.counts.typecnt) return error.Malformed; // rfc8536: isstdcnt [...] MUST either be zero or equal to "typecnt"
if (header.counts.isutcnt != 0 and header.counts.isutcnt != header.counts.typecnt) return error.Malformed; // rfc8536: isutcnt [...] MUST either be zero or equal to "typecnt"
if (header.counts.typecnt == 0) return error.Malformed; // rfc8536: typecnt [...] MUST NOT be zero
@ -98,12 +101,12 @@ pub const Tz = struct {
// Parse transition types
var i: usize = 0;
while (i < header.counts.timecnt) : (i += 1) {
transitions[i].ts = if (legacy) try reader.readInt(i32, .big) else try reader.readInt(i64, .big);
transitions[i].ts = if (legacy) try reader.takeInt(i32, .big) else try reader.takeInt(i64, .big);
}
i = 0;
while (i < header.counts.timecnt) : (i += 1) {
const tt = try reader.readByte();
const tt = try reader.takeByte();
if (tt >= timetypes.len) return error.Malformed; // rfc8536: Each type index MUST be in the range [0, "typecnt" - 1]
transitions[i].timetype = &timetypes[tt];
}
@ -111,11 +114,11 @@ pub const Tz = struct {
// Parse time types
i = 0;
while (i < header.counts.typecnt) : (i += 1) {
const offset = try reader.readInt(i32, .big);
const offset = try reader.takeInt(i32, .big);
if (offset < -2147483648) return error.Malformed; // rfc8536: utoff [...] MUST NOT be -2**31
const dst = try reader.readByte();
const dst = try reader.takeByte();
if (dst != 0 and dst != 1) return error.Malformed; // rfc8536: (is)dst [...] The value MUST be 0 or 1.
const idx = try reader.readByte();
const idx = try reader.takeByte();
if (idx > header.counts.charcnt - 1) return error.Malformed; // rfc8536: (desig)idx [...] Each index MUST be in the range [0, "charcnt" - 1]
timetypes[i] = .{
.offset = offset,
@ -128,7 +131,7 @@ pub const Tz = struct {
}
var designators_data: [256 + 6]u8 = undefined;
try reader.readNoEof(designators_data[0..header.counts.charcnt]);
try reader.readSliceAll(designators_data[0..header.counts.charcnt]);
const designators = designators_data[0..header.counts.charcnt];
if (designators[designators.len - 1] != 0) return error.Malformed; // rfc8536: charcnt [...] includes the trailing NUL (0x00) octet
@ -144,12 +147,12 @@ pub const Tz = struct {
// Parse leap seconds
i = 0;
while (i < header.counts.leapcnt) : (i += 1) {
const occur: i64 = if (legacy) try reader.readInt(i32, .big) else try reader.readInt(i64, .big);
const occur: i64 = if (legacy) try reader.takeInt(i32, .big) else try reader.takeInt(i64, .big);
if (occur < 0) return error.Malformed; // rfc8536: occur [...] MUST be nonnegative
if (i > 0 and leapseconds[i - 1].occurrence + 2419199 > occur) return error.Malformed; // rfc8536: occur [...] each later value MUST be at least 2419199 greater than the previous value
if (occur > std.math.maxInt(i48)) return error.Malformed; // Unreasonably far into the future
const corr = try reader.readInt(i32, .big);
const corr = try reader.takeInt(i32, .big);
if (i == 0 and corr != -1 and corr != 1) return error.Malformed; // rfc8536: The correction value in the first leap-second record, if present, MUST be either one (1) or minus one (-1)
if (i > 0 and leapseconds[i - 1].correction != corr + 1 and leapseconds[i - 1].correction != corr - 1) return error.Malformed; // rfc8536: The correction values in adjacent leap-second records MUST differ by exactly one (1)
if (corr > std.math.maxInt(i16)) return error.Malformed; // Unreasonably large correction
@ -163,7 +166,7 @@ pub const Tz = struct {
// Parse standard/wall indicators
i = 0;
while (i < header.counts.isstdcnt) : (i += 1) {
const stdtime = try reader.readByte();
const stdtime = try reader.takeByte();
if (stdtime == 1) {
timetypes[i].flags |= 0x02;
}
@ -172,7 +175,7 @@ pub const Tz = struct {
// Parse UT/local indicators
i = 0;
while (i < header.counts.isutcnt) : (i += 1) {
const ut = try reader.readByte();
const ut = try reader.takeByte();
if (ut == 1) {
timetypes[i].flags |= 0x04;
if (!timetypes[i].standardTimeIndicator()) return error.Malformed; // rfc8536: standard/wall value MUST be one (1) if the UT/local value is one (1)
@ -182,9 +185,8 @@ pub const Tz = struct {
// Footer
var footer: ?[]u8 = null;
if (!legacy) {
if ((try reader.readByte()) != '\n') return error.Malformed; // An rfc8536 footer must start with a newline
var footerdata_buf: [128]u8 = undefined;
const footer_mem = reader.readUntilDelimiter(&footerdata_buf, '\n') catch |err| switch (err) {
if ((try reader.takeByte()) != '\n') return error.Malformed; // An rfc8536 footer must start with a newline
const footer_mem = reader.takeSentinel('\n') catch |err| switch (err) {
error.StreamTooLong => return error.OverlargeFooter, // Read more than 128 bytes, much larger than any reasonable POSIX TZ string
else => return err,
};
@ -194,7 +196,7 @@ pub const Tz = struct {
}
errdefer if (footer) |ft| allocator.free(ft);
return Tz{
return .{
.allocator = allocator,
.transitions = transitions,
.timetypes = timetypes,
@ -215,9 +217,9 @@ pub const Tz = struct {
test "slim" {
const data = @embedFile("tz/asia_tokyo.tzif");
var in_stream = std.io.fixedBufferStream(data);
var in_stream: Reader = .fixed(data);
var tz = try std.Tz.parse(std.testing.allocator, in_stream.reader());
var tz = try std.Tz.parse(std.testing.allocator, &in_stream);
defer tz.deinit();
try std.testing.expectEqual(tz.transitions.len, 9);
@ -228,9 +230,9 @@ test "slim" {
test "fat" {
const data = @embedFile("tz/antarctica_davis.tzif");
var in_stream = std.io.fixedBufferStream(data);
var in_stream: Reader = .fixed(data);
var tz = try std.Tz.parse(std.testing.allocator, in_stream.reader());
var tz = try std.Tz.parse(std.testing.allocator, &in_stream);
defer tz.deinit();
try std.testing.expectEqual(tz.transitions.len, 8);
@ -241,9 +243,9 @@ test "fat" {
test "legacy" {
// Taken from Slackware 8.0, from 2001
const data = @embedFile("tz/europe_vatican.tzif");
var in_stream = std.io.fixedBufferStream(data);
var in_stream: Reader = .fixed(data);
var tz = try std.Tz.parse(std.testing.allocator, in_stream.reader());
var tz = try std.Tz.parse(std.testing.allocator, &in_stream);
defer tz.deinit();
try std.testing.expectEqual(tz.transitions.len, 170);