llgo/ssa: allocaCStr; runtime: String

internal/runtime/z_string.go

@@ -18,6 +18,8 @@ package runtime
 
 import (
 	"unsafe"
+
+	"github.com/goplus/llgo/internal/runtime/c"
 )
 
 // -----------------------------------------------------------------------------
@@ -38,4 +40,28 @@ func EmptyString() String {
 	return String{nil, 0}
 }
 
+// StringLen returns the length of a string.
+func StringLen(s Slice) int {
+	return s.len
+}
+
+// StringData returns the data pointer of a string.
+func StringData(s String) unsafe.Pointer {
+	return s.data
+}
+
+// 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 := Alloc(uintptr(s.len + 1))
+	return CStrCopy(dest, s)
+}
+
 // -----------------------------------------------------------------------------