94 lines
2.5 KiB
Go
94 lines
2.5 KiB
Go
/*
|
|
* Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
package runtime
|
|
|
|
import (
|
|
"unsafe"
|
|
|
|
"github.com/goplus/llgo/internal/runtime/c"
|
|
)
|
|
|
|
// -----------------------------------------------------------------------------
|
|
|
|
// String is the runtime representation of a string.
|
|
// It cannot be used safely or portably and its representation may
|
|
// change in a later release.
|
|
//
|
|
// Unlike reflect.StringHeader, its Data field is sufficient to guarantee the
|
|
// data it references will not be garbage collected.
|
|
type String struct {
|
|
data unsafe.Pointer
|
|
len int
|
|
}
|
|
|
|
// EmptyString returns an empty string.
|
|
func EmptyString() String {
|
|
return String{nil, 0}
|
|
}
|
|
|
|
// NewString creates a new string.
|
|
func NewString(data unsafe.Pointer, len int) String {
|
|
return String{data, len}
|
|
}
|
|
|
|
// StringLen returns the length of a string.
|
|
func StringLen(s String) int {
|
|
return s.len
|
|
}
|
|
|
|
// StringData returns the data pointer of a string.
|
|
func StringData(s String) unsafe.Pointer {
|
|
return s.data
|
|
}
|
|
|
|
// StringCat concatenates two strings.
|
|
func StringCat(a, b String) String {
|
|
n := a.len + b.len
|
|
dest := AllocU(uintptr(n))
|
|
c.Memcpy(dest, a.data, uintptr(a.len))
|
|
c.Memcpy(c.Advance(dest, a.len), b.data, uintptr(b.len))
|
|
return String{dest, n}
|
|
}
|
|
|
|
// -----------------------------------------------------------------------------
|
|
|
|
// CStrCopy copies a Go string to a C string buffer and returns it.
|
|
func CStrCopy(dest unsafe.Pointer, s String) *int8 {
|
|
n := s.len
|
|
c.Memcpy(dest, s.data, uintptr(n))
|
|
arr := (*[1 << 30]int8)(dest)
|
|
arr[n] = 0
|
|
return (*int8)(dest)
|
|
}
|
|
|
|
func CStrDup(s String) *int8 {
|
|
dest := AllocU(uintptr(s.len + 1))
|
|
return CStrCopy(dest, s)
|
|
}
|
|
|
|
func NewStringSlice(base String, i, j int) String {
|
|
if i < 0 || j < i || j > base.len {
|
|
panic("string slice index out of bounds")
|
|
}
|
|
if i < base.len {
|
|
return String{c.Advance(base.data, i), j - i}
|
|
}
|
|
return String{nil, 0}
|
|
}
|
|
|
|
// -----------------------------------------------------------------------------
|