ona/source/coral/io.zig

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const debug = @import("./debug.zig");
const math = @import("./math.zig");
pub const AllocationError = error {
OutOfMemory,
};
pub const Allocator = struct {
context: *anyopaque,
actions: *const struct {
deallocate: *const fn (context: *anyopaque, allocation: []Byte) void,
reallocate: *const fn (context: *anyopaque, return_address: usize, existing_allocation: ?[]Byte, size: usize) AllocationError![]Byte,
},
pub fn Actions(comptime State: type) type {
return struct {
deallocate: fn (state: *State, allocation: []Byte) void,
reallocate: fn (state: *State, return_address: usize, existing_allocation: ?[]Byte, size: usize) AllocationError![]Byte,
};
}
pub fn bind(comptime State: type, state: *State, comptime actions: Actions(State)) Allocator {
const is_zero_aligned = @alignOf(State) == 0;
const ErasedActions = struct {
fn deallocate(context: *anyopaque, allocation: []Byte) void {
if (is_zero_aligned) {
return actions.deallocator(@ptrCast(context), allocation);
}
return actions.deallocate(@ptrCast(@alignCast(context)), allocation);
}
fn reallocate(context: *anyopaque, return_address: usize, existing_allocation: ?[]Byte, size: usize) AllocationError![]Byte {
if (is_zero_aligned) {
return actions.reallocator(@ptrCast(context), return_address, existing_allocation, size);
}
return actions.reallocate(@ptrCast(@alignCast(context)), return_address, existing_allocation, size);
}
};
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return .{
.context = if (is_zero_aligned) state else @ptrCast(state),
.actions = &.{
.deallocate = ErasedActions.deallocate,
.reallocate = ErasedActions.reallocate,
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}
};
}
pub fn deallocate(self: Allocator, allocation: anytype) void {
switch (@typeInfo(@TypeOf(allocation))) {
.Pointer => |pointer| {
self.actions.deallocate(self.context, switch (pointer.size) {
.One => @as([*]Byte, @ptrCast(allocation))[0 .. @sizeOf(pointer.child)],
.Slice => @as([*]Byte, @ptrCast(allocation.ptr))[0 .. (@sizeOf(pointer.child) * allocation.len)],
.Many, .C => @compileError("length of allocation must be known to deallocate"),
});
},
else => @compileError("cannot deallocate " ++ allocation),
}
}
pub fn reallocate(self: Allocator, allocation: ?[]Byte, allocation_size: usize) AllocationError![]Byte {
return self.actions.reallocate(self.context, @returnAddress(), allocation, allocation_size);
}
};
pub const Byte = u8;
pub const FixedBuffer = struct {
bytes: []Byte,
pub fn as_writer(self: *FixedBuffer) Writer {
return Writer.bind(FixedBuffer, self, struct {
fn write(writable_memory: *FixedBuffer, data: []const Byte) ?usize {
return writable_memory.write(data);
}
}.write);
}
pub fn put(self: *FixedBuffer, byte: Byte) bool {
if (self.bytes.len == 0) {
return false;
}
self.bytes[0] = byte;
self.bytes = self.bytes[1 ..];
return true;
}
pub fn write(self: *FixedBuffer, bytes: []const Byte) usize {
const writable = math.min(self.bytes.len, bytes.len);
copy(self.bytes, bytes);
self.bytes = self.bytes[writable ..];
return writable;
}
};
pub fn Functor(comptime Output: type, comptime Input: type) type {
return struct {
context: *const anyopaque,
invoker: *const fn (capture: *const anyopaque, input: Input) Output,
const Self = @This();
pub fn bind(comptime State: type, state: *const State, comptime invoker: fn (capture: *const State, input: Input) Output) Self {
const is_zero_aligned = @alignOf(State) == 0;
return .{
.context = if (is_zero_aligned) state else @ptrCast(state),
.invoker = struct {
fn invoke(context: *const anyopaque, input: Input) Output {
if (is_zero_aligned) {
return invoker(@ptrCast(context), input);
}
return invoker(@ptrCast(@alignCast(context)), input);
}
}.invoke,
};
}
pub fn invoke(self: Self, input: Input) Output {
return self.invoker(self.context, input);
}
};
}
pub fn Generator(comptime Output: type, comptime Input: type) type {
return struct {
context: *anyopaque,
invoker: *const fn (capture: *anyopaque, input: Input) Output,
const Self = @This();
pub fn bind(comptime State: type, state: *State, comptime invoker: fn (capture: *State, input: Input) Output) Self {
const is_zero_aligned = @alignOf(State) == 0;
return .{
.context = if (is_zero_aligned) state else @ptrCast(state),
.invoker = struct {
fn invoke(context: *anyopaque, input: Input) Output {
if (is_zero_aligned) {
return invoker(@ptrCast(context), input);
}
return invoker(@ptrCast(@alignCast(context)), input);
}
}.invoke,
};
}
pub fn invoke(self: Self, input: Input) Output {
return self.invoker(self.context, input);
}
};
}
pub fn Tag(comptime Element: type) type {
return switch (@typeInfo(Element)) {
.Enum => |info| info.tag_type,
.Union => |info| info.tag_type orelse @compileError(@typeName(Element) ++ " has no tag type"),
else => @compileError("expected enum or union type, found '" ++ @typeName(Element) ++ "'"),
};
}
pub const Writer = Generator(?usize, []const Byte);
pub fn allocate_copy(allocator: Allocator, source: []const Byte) AllocationError![]Byte {
const allocation = try allocator.actions.reallocate(allocator.context, @returnAddress(), null, source.len);
copy(allocation, source);
return allocation;
}
pub fn allocate_one(allocator: Allocator, value: anytype) AllocationError!*@TypeOf(value) {
const Type = @TypeOf(value);
const typeSize = @sizeOf(Type);
if (typeSize == 0) {
@compileError("Cannot allocate memory for 0-byte sized type " ++ @typeName(Type));
}
const allocation = @as(*Type, @ptrCast(@alignCast(try allocator.actions.reallocate(
allocator.context,
@returnAddress(),
null,
typeSize))));
allocation.* = value;
return allocation;
}
pub fn bytes_of(value: anytype) []const Byte {
const pointer_info = @typeInfo(@TypeOf(value)).Pointer;
return switch (pointer_info.size) {
.One => @as([*]const Byte, @ptrCast(value))[0 .. @sizeOf(pointer_info.child)],
.Slice => @as([*]const Byte, @ptrCast(value.ptr))[0 .. @sizeOf(pointer_info.child) * value.len],
else => @compileError("`value` must be single-element pointer or slice type"),
};
}
pub fn copy(target: []Byte, source: []const Byte) void {
var index: usize = 0;
while (index < source.len) : (index += 1) {
target[index] = source[index];
}
}
pub fn ends_with(target: []const Byte, match: []const Byte) bool {
if (target.len < match.len) {
return false;
}
{
var index = @as(usize, 0);
while (index < match.len) : (index += 1) {
if (target[target.len - (1 + index)] != match[match.len - (1 + index)]) {
return false;
}
}
}
return true;
}
pub fn equals(target: []const Byte, match: []const Byte) bool {
if (target.len != match.len) {
return false;
}
for (0 .. target.len) |index| {
if (target[index] != match[index]) {
return false;
}
}
return true;
}
var null_context = @as(usize, 0);
pub const null_writer = Writer.bind(usize, &null_context, struct {
fn write(context: *usize, buffer: []const u8) ?usize {
debug.assert(context.* == 0);
return buffer.len;
}
}.write);
pub fn slice_sentineled(comptime sen: anytype, ptr: [*:sen]const @TypeOf(sen)) [:sen]const @TypeOf(sen) {
var len = @as(usize, 0);
while (ptr[len] != sen) {
len += 1;
}
return ptr[0 .. len:sen];
}
pub fn tag_of(comptime value: anytype) Tag(@TypeOf(value)) {
return @as(Tag(@TypeOf(value)), value);
}
pub fn zero(target: []Byte) void {
for (target) |*t| t.* = 0;
}