std.time: Make Instant.since() work on UEFI

This commit is contained in:
Linus Groh 2025-03-02 22:31:47 +00:00
parent 1a03b8c899
commit 3bea47883a

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@ -135,7 +135,7 @@ pub const Instant = struct {
const clock_id = switch (builtin.os.tag) { const clock_id = switch (builtin.os.tag) {
.windows => { .windows => {
// QPC on windows doesn't fail on >= XP/2000 and includes time suspended. // QPC on windows doesn't fail on >= XP/2000 and includes time suspended.
return Instant{ .timestamp = windows.QueryPerformanceCounter() }; return .{ .timestamp = windows.QueryPerformanceCounter() };
}, },
.wasi => { .wasi => {
var ns: std.os.wasi.timestamp_t = undefined; var ns: std.os.wasi.timestamp_t = undefined;
@ -147,7 +147,7 @@ pub const Instant = struct {
var value: std.os.uefi.Time = undefined; var value: std.os.uefi.Time = undefined;
const status = std.os.uefi.system_table.runtime_services.getTime(&value, null); const status = std.os.uefi.system_table.runtime_services.getTime(&value, null);
if (status != .success) return error.Unsupported; if (status != .success) return error.Unsupported;
return Instant{ .timestamp = value.toEpoch() }; return .{ .timestamp = value.toEpoch() };
}, },
// On darwin, use UPTIME_RAW instead of MONOTONIC as it ticks while // On darwin, use UPTIME_RAW instead of MONOTONIC as it ticks while
// suspended. // suspended.
@ -185,7 +185,8 @@ pub const Instant = struct {
/// This assumes that the `earlier` Instant represents a moment in time before or equal to `self`. /// This assumes that the `earlier` Instant represents a moment in time before or equal to `self`.
/// This also assumes that the time that has passed between both Instants fits inside a u64 (~585 yrs). /// This also assumes that the time that has passed between both Instants fits inside a u64 (~585 yrs).
pub fn since(self: Instant, earlier: Instant) u64 { pub fn since(self: Instant, earlier: Instant) u64 {
if (builtin.os.tag == .windows) { switch (builtin.os.tag) {
.windows => {
// We don't need to cache QPF as it's internally just a memory read to KUSER_SHARED_DATA // We don't need to cache QPF as it's internally just a memory read to KUSER_SHARED_DATA
// (a read-only page of info updated and mapped by the kernel to all processes): // (a read-only page of info updated and mapped by the kernel to all processes):
// https://docs.microsoft.com/en-us/windows-hardware/drivers/ddi/ntddk/ns-ntddk-kuser_shared_data // https://docs.microsoft.com/en-us/windows-hardware/drivers/ddi/ntddk/ns-ntddk-kuser_shared_data
@ -204,17 +205,18 @@ pub const Instant = struct {
const scale = @as(u64, std.time.ns_per_s << 32) / @as(u32, @intCast(qpf)); const scale = @as(u64, std.time.ns_per_s << 32) / @as(u32, @intCast(qpf));
const result = (@as(u96, qpc) * scale) >> 32; const result = (@as(u96, qpc) * scale) >> 32;
return @as(u64, @truncate(result)); return @as(u64, @truncate(result));
} },
.uefi, .wasi => {
// WASI timestamps are directly in nanoseconds // UEFI and WASI timestamps are directly in nanoseconds
if (builtin.os.tag == .wasi) {
return self.timestamp - earlier.timestamp; return self.timestamp - earlier.timestamp;
} },
else => {
// Convert timespec diff to ns // Convert timespec diff to ns
const seconds = @as(u64, @intCast(self.timestamp.sec - earlier.timestamp.sec)); const seconds = @as(u64, @intCast(self.timestamp.sec - earlier.timestamp.sec));
const elapsed = (seconds * ns_per_s) + @as(u32, @intCast(self.timestamp.nsec)); const elapsed = (seconds * ns_per_s) + @as(u32, @intCast(self.timestamp.nsec));
return elapsed - @as(u32, @intCast(earlier.timestamp.nsec)); return elapsed - @as(u32, @intCast(earlier.timestamp.nsec));
},
}
} }
}; };