Files
bun.sh/src/string/StringBuilder.zig
Jarred Sumner f34a04d80a here
2025-06-18 14:48:20 -07:00

274 lines
8.6 KiB
Zig

const StringBuilder = @This();
const std = @import("std");
const bun = @import("bun");
const Allocator = std.mem.Allocator;
const Environment = bun.Environment;
const assert = bun.assert;
len: usize = 0,
cap: usize = 0,
ptr: ?[*]u8 = null,
pub fn initCapacity(
allocator: std.mem.Allocator,
cap: usize,
) Allocator.Error!StringBuilder {
return StringBuilder{
.cap = cap,
.len = 0,
.ptr = (try allocator.alloc(u8, cap)).ptr,
};
}
pub fn countZ(this: *StringBuilder, slice: []const u8) void {
this.cap += slice.len + 1;
}
pub fn count(this: *StringBuilder, slice: []const u8) void {
this.cap += slice.len;
}
pub fn allocate(this: *StringBuilder, allocator: Allocator) Allocator.Error!void {
const slice = try allocator.alloc(u8, this.cap);
this.ptr = slice.ptr;
this.len = 0;
}
/// Allocates a null-terminated slice in a single allocation.
pub fn createNullDelimited(allocator: Allocator, args: anytype) Allocator.Error!struct { [*:null]?[*:0]const u8, []u8 } {
var this = bun.StringBuilder{};
for (args) |arg| {
this.countZ(arg);
}
const byte_len = this.cap + ((args.len + 1) * @sizeOf([*:0]const u8));
// Slice of:
// ptrs: [*:null][*:0]const u8
// bytes: [*]u8
const raw_bytes = allocator.rawAlloc(
byte_len,
.@"8",
@returnAddress(),
) orelse return error.OutOfMemory;
const allocated_bytes = raw_bytes[0..byte_len];
const ptrs: [*:null]?[*:0]const u8 = @alignCast(@ptrCast(allocated_bytes.ptr));
const bytes: []u8 = allocated_bytes[((args.len + 1) * @sizeOf([*:0]const u8))..];
this.ptr = bytes.ptr;
for (ptrs[0..args.len], args) |*ptr, arg| {
ptr.* = this.appendZ(arg).ptr;
}
ptrs[args.len] = null;
return .{ ptrs, bytes };
}
pub fn deinit(this: *StringBuilder, allocator: Allocator) void {
if (this.ptr == null or this.cap == 0) return;
allocator.free(this.ptr.?[0..this.cap]);
}
pub fn count16(this: *StringBuilder, slice: []const u16) void {
const result = bun.simdutf.length.utf8.from.utf16.le(slice);
this.cap += result;
}
pub fn count16Z(this: *StringBuilder, slice: [:0]const u16) void {
const result = bun.strings.elementLengthUTF16IntoUTF8([:0]const u16, slice);
this.cap += result + 1;
}
pub fn append16(this: *StringBuilder, slice: []const u16, fallback_allocator: std.mem.Allocator) ?[:0]u8 {
var buf = this.writable();
if (slice.len == 0) {
buf[0] = 0;
this.len += 1;
return buf[0..0 :0];
}
const result = bun.simdutf.convert.utf16.to.utf8.with_errors.le(slice, buf);
if (result.status == .success) {
this.len += result.count + 1;
buf[result.count] = 0;
return buf[0..result.count :0];
} else {
var list = std.ArrayList(u8).init(fallback_allocator);
var out = bun.strings.toUTF8ListWithTypeBun(&list, []const u16, slice, false) catch return null;
out.append(0) catch return null;
return list.items[0 .. list.items.len - 1 :0];
}
}
pub fn appendZ(this: *StringBuilder, slice: []const u8) [:0]const u8 {
if (comptime Environment.allow_assert) {
assert(this.len + 1 <= this.cap); // didn't count everything
assert(this.ptr != null); // must call allocate first
}
bun.copy(u8, this.ptr.?[this.len..this.cap], slice);
this.ptr.?[this.len + slice.len] = 0;
const result = this.ptr.?[this.len..this.cap][0..slice.len :0];
this.len += slice.len + 1;
if (comptime Environment.allow_assert) assert(this.len <= this.cap);
return result;
}
pub fn appendStr(this: *StringBuilder, str: bun.String) []const u8 {
const slice = str.toUTF8(bun.default_allocator);
defer slice.deinit();
return this.append(slice.slice());
}
pub fn append(this: *StringBuilder, slice: []const u8) []const u8 {
if (comptime Environment.allow_assert) {
assert(this.len <= this.cap); // didn't count everything
assert(this.ptr != null); // must call allocate first
}
bun.copy(u8, this.ptr.?[this.len..this.cap], slice);
const result = this.ptr.?[this.len..this.cap][0..slice.len];
this.len += slice.len;
if (comptime Environment.allow_assert) assert(this.len <= this.cap);
return result;
}
pub fn addConcat(this: *StringBuilder, slices: []const []const u8) bun.StringPointer {
var remain = this.allocatedSlice()[this.len..];
var len: usize = 0;
for (slices) |slice| {
@memcpy(remain[0..slice.len], slice);
remain = remain[slice.len..];
len += slice.len;
}
return this.add(len);
}
pub fn add(this: *StringBuilder, len: usize) bun.StringPointer {
if (comptime Environment.allow_assert) {
assert(this.len <= this.cap); // didn't count everything
assert(this.ptr != null); // must call allocate first
}
const start = this.len;
this.len += len;
if (comptime Environment.allow_assert) assert(this.len <= this.cap);
return bun.StringPointer{ .offset = @as(u32, @truncate(start)), .length = @as(u32, @truncate(len)) };
}
pub fn appendCount(this: *StringBuilder, slice: []const u8) bun.StringPointer {
if (comptime Environment.allow_assert) {
assert(this.len <= this.cap); // didn't count everything
assert(this.ptr != null); // must call allocate first
}
const start = this.len;
bun.copy(u8, this.ptr.?[this.len..this.cap], slice);
const result = this.ptr.?[this.len..this.cap][0..slice.len];
_ = result;
this.len += slice.len;
if (comptime Environment.allow_assert) assert(this.len <= this.cap);
return bun.StringPointer{ .offset = @as(u32, @truncate(start)), .length = @as(u32, @truncate(slice.len)) };
}
pub fn appendCountZ(this: *StringBuilder, slice: []const u8) bun.StringPointer {
if (comptime Environment.allow_assert) {
assert(this.len <= this.cap); // didn't count everything
assert(this.ptr != null); // must call allocate first
}
const start = this.len;
bun.copy(u8, this.ptr.?[this.len..this.cap], slice);
this.ptr.?[this.len + slice.len] = 0;
const result = this.ptr.?[this.len..this.cap][0..slice.len];
_ = result;
this.len += slice.len;
this.len += 1;
if (comptime Environment.allow_assert) assert(this.len <= this.cap);
return bun.StringPointer{ .offset = @as(u32, @truncate(start)), .length = @as(u32, @truncate(slice.len)) };
}
pub fn fmt(this: *StringBuilder, comptime str: []const u8, args: anytype) []const u8 {
if (comptime Environment.allow_assert) {
assert(this.len <= this.cap); // didn't count everything
assert(this.ptr != null); // must call allocate first
}
const buf = this.ptr.?[this.len..this.cap];
const out = std.fmt.bufPrint(buf, str, args) catch unreachable;
this.len += out.len;
if (comptime Environment.allow_assert) assert(this.len <= this.cap);
return out;
}
pub fn fmtAppendCount(this: *StringBuilder, comptime str: []const u8, args: anytype) bun.StringPointer {
if (comptime Environment.allow_assert) {
assert(this.len <= this.cap); // didn't count everything
assert(this.ptr != null); // must call allocate first
}
const buf = this.ptr.?[this.len..this.cap];
const out = std.fmt.bufPrint(buf, str, args) catch unreachable;
const off = this.len;
this.len += out.len;
if (comptime Environment.allow_assert) assert(this.len <= this.cap);
return bun.StringPointer{
.offset = @as(u32, @truncate(off)),
.length = @as(u32, @truncate(out.len)),
};
}
pub fn fmtAppendCountZ(this: *StringBuilder, comptime str: []const u8, args: anytype) bun.StringPointer {
if (comptime Environment.allow_assert) {
assert(this.len <= this.cap); // didn't count everything
assert(this.ptr != null); // must call allocate first
}
const buf = this.ptr.?[this.len..this.cap];
const out = std.fmt.bufPrintZ(buf, str, args) catch unreachable;
const off = this.len;
this.len += out.len;
this.len += 1;
if (comptime Environment.allow_assert) assert(this.len <= this.cap);
return bun.StringPointer{
.offset = @as(u32, @truncate(off)),
.length = @as(u32, @truncate(out.len)),
};
}
pub fn fmtCount(this: *StringBuilder, comptime str: []const u8, args: anytype) void {
this.cap += std.fmt.count(str, args);
}
pub fn allocatedSlice(this: *StringBuilder) []u8 {
var ptr = this.ptr orelse return &[_]u8{};
if (comptime Environment.allow_assert) {
assert(this.cap > 0);
}
return ptr[0..this.cap];
}
pub fn writable(this: *StringBuilder) []u8 {
var ptr = this.ptr orelse return &[_]u8{};
if (comptime Environment.allow_assert) {
assert(this.cap > 0);
}
return ptr[this.len..this.cap];
}