Remove strdup/strndup when cloning Go strings.

c_expr.go

@@ -1438,9 +1438,8 @@ func (e *SliceExpr) HasSideEffects() bool {
 	return false
 }
 
-func (e *SliceExpr) CType(types.Type) types.Type {
-	arr := types.Unwrap(e.Expr.CType(nil)).(types.ArrayType)
-	return types.SliceT(arr.Elem())
+func (e *SliceExpr) CType(exp types.Type) types.Type {
+	return e.Expr.CType(exp)
 }
 
 func (e *SliceExpr) AsExpr() GoExpr {

funcs.go

@@ -143,6 +143,20 @@ func (g *translator) NewCCallExpr(fnc FuncExpr, args []Expr) Expr {
 					}
 				}
 			}
+		case g.env.C().StrdupFunc():
+			// strdup(string) -> string
+			if len(args) == 1 {
+				if args[0].CType(nil) == g.env.Go().String() {
+					return args[0]
+				}
+			}
+		case g.env.C().StrndupFunc():
+			// strndup(string, n) -> string[:n]
+			if len(args) == 2 {
+				if args[0].CType(nil) == g.env.Go().String() {
+					return &SliceExpr{Expr: args[0], High: args[1]}
+				}
+			}
 		case g.env.Go().SliceFunc():
 			// _slice(arr, -1, 1) -> arr[:1]
 			if len(args) == 3 || len(args) == 4 {

libs/builtin.go

@@ -187,6 +187,8 @@ void* malloc(_cxgo_go_int);
 			c.C().MemmoveFunc(),
 			c.C().MemcpyFunc(),
 			c.C().MemsetFunc(),
+			c.C().StrdupFunc(),
+			c.C().StrndupFunc(),
 			c.NewIdent("_cxgo_func_name", "libc.FuncName", libc.FuncName, c.FuncTT(c.Go().String())),
 			c.NewIdent("__builtin_strcpy", "libc.StrCpy", libc.StrCpy, c.FuncTT(charP, charP, charP)),
 			c.NewIdent("__sync_lock_test_and_set", "atomic.SwapInt32", atomic.SwapInt32, c.FuncTT(int32T, c.PtrT(int32T), int32T)),

libs/string.go

@@ -35,8 +35,6 @@ func init() {
 				"strtok":      c.NewIdent("strtok", "libc.StrTok", libc.StrTok, c.FuncTT(cstrT, cstrT, cstrT)),
 				"strspn":      c.NewIdent("strspn", "libc.StrSpn", libc.StrSpn, c.FuncTT(gintT, cstrT, cstrT)),
 				"strcspn":     c.NewIdent("strcspn", "libc.StrCSpn", libc.StrCSpn, c.FuncTT(gintT, cstrT, cstrT)),
-				"strdup":      c.NewIdent("strdup", "libc.StrDup", libc.StrDup, c.FuncTT(cstrT, cstrT)),
-				"strndup":     c.NewIdent("strndup", "libc.StrNDup", libc.StrNDup, c.FuncTT(cstrT, cstrT, gintT)),
 			},
 			Header: `
 #include <` + BuiltinH + `>
@@ -59,15 +57,15 @@ _cxgo_go_int      strcoll(const char *, const char *);
 //int      strcoll_l(const char *, const char *, locale_t);
 char    *strcpy(char *restrict, const char *restrict);
 _cxgo_go_int   strcspn(const char *, const char *);
-char    *strdup(const char *);
+#define strdup __builtin_strdup
+#define strndup __builtin_strndup
 char    *strerror(int);
 //char    *strerror_l(int, locale_t);
 int      strerror_r(int, char *, size_t);
 _cxgo_go_int   strlen(const char *);
 char    *strncat(char *restrict, const char *restrict, _cxgo_go_int);
 _cxgo_go_int      strncmp(const char *, const char *, _cxgo_go_int);
 char    *strncpy(char *restrict, const char *restrict, _cxgo_go_int);
-char    *strndup(const char *, _cxgo_go_int);
 _cxgo_go_int   strnlen(const char *, _cxgo_go_int);
 char    *strpbrk(const char *, const char *);
 char    *strrchr(const char *, _cxgo_go_byte);

types/env_c.go

@@ -16,6 +16,8 @@ type C struct {
 	memmoveF *Ident
 	memcpyF  *Ident
 	memsetF  *Ident
+	strdupF  *Ident
+	strndupF *Ident
 }
 
 // C returns a package containing builtin C types.
@@ -60,12 +62,15 @@ func (c *C) init() {
 	c.pkg.NewAlias("_QWORD", "", UintT(8))
 
 	unsafePtr := g.UnsafePtr()
+	cstring := c.String()
 	c.mallocF = NewIdentGo("__builtin_malloc", "libc.Malloc", c.e.FuncTT(unsafePtr, g.Int()))
 	c.freeF = NewIdentGo("free", "libc.Free", c.e.FuncTT(nil, unsafePtr))
 	c.callocF = NewIdentGo("calloc", "libc.Calloc", c.e.FuncTT(unsafePtr, g.Int(), g.Int()))
 	c.memmoveF = NewIdentGo("__builtin_memmove", "libc.MemMove", c.e.FuncTT(unsafePtr, unsafePtr, unsafePtr, g.Int()))
 	c.memcpyF = NewIdentGo("__builtin_memcpy", "libc.MemCpy", c.e.FuncTT(unsafePtr, unsafePtr, unsafePtr, g.Int()))
 	c.memsetF = NewIdentGo("__builtin_memset", "libc.MemSet", c.e.FuncTT(unsafePtr, unsafePtr, g.Byte(), g.Int()))
+	c.strdupF = NewIdentGo("__builtin_strdup", "libc.StrDup", c.e.FuncTT(cstring, cstring))
+	c.strndupF = NewIdentGo("__builtin_strndup", "libc.StrNDup", c.e.FuncTT(cstring, cstring, g.Int()))
 }
 
 func (c *C) WCharSize() int {
@@ -234,3 +239,13 @@ func (c *C) MemcpyFunc() *Ident {
 func (c *C) MemsetFunc() *Ident {
 	return c.memsetF
 }
+
+// StrdupFunc returns C strdup function ident.
+func (c *C) StrdupFunc() *Ident {
+	return c.strdupF
+}
+
+// StrndupFunc returns C strndup function ident.
+func (c *C) StrndupFunc() *Ident {
+	return c.strndupF
+}