Merge 46cc281099bfad78ee697e700330314307235695 into 71f06c4ff1c80e015c3da7b97da439815ca0c80f

Adds an optional open_file callback to py_Callbacks, consulted before
script-reachable file operations:

  - io.FileIO(path, mode): called with the fopen mode string before the open
  - os.remove(path): called with the literal "delete"

Returning false rejects the operation and raises OSError; returning true
(or leaving the callback NULL, which is the default) allows it. Existing
embedders are unaffected -- the default is NULL and behavior is unchanged.

This lets an embedder enforce its own path policy using its own
canonicalization instead of reimplementing path checks inside the VM.

.github/workflows/main.yml

@@ -56,11 +56,11 @@ jobs:
     - name: Setup Clang
       uses: egor-tensin/setup-clang@v1
       with:
-        version: 17
+        version: 19
         platform: x64
     - name: Run Sanitizers
       run: |
-        sudo apt-get install -y libclang-rt-17-dev
+        sudo apt-get install -y libclang-rt-19-dev
         bash build_g.sh
         bash run_tests.sh
         rm -rf ./main

include/pocketpy/objects/base.h

@@ -4,7 +4,7 @@
 
 typedef struct PyObject PyObject;
 typedef struct VM VM;
-extern _Thread_local VM* pk_current_vm;
+extern PK_THREAD_LOCAL VM* pk_current_vm;
 
 typedef struct py_TValue {
     py_Type type;

include/pocketpy/pocketpy.h

@@ -78,6 +78,13 @@ typedef struct py_Callbacks {
     PY_MAYBENULL void (*gc_mark)(void (*f)(py_Ref val, void* ctx), void* ctx);
     /// Used by `PRINT_EXPR` bytecode.
     PY_MAYBENULL bool (*displayhook)(py_Ref val) PY_RAISE;
+    // open_file hook contributed by fdtd.io (Hector), 2026.
+    /// Consulted before a script-reachable file operation. `path` is the target path;
+    /// `mode` is the fopen mode string for `io.FileIO`, or the literal "delete" for
+    /// `os.remove`. Return true to allow the operation, false to reject it (the binding
+    /// then raises OSError). NULL (the default) allows everything, so existing embedders
+    /// are unaffected. Lets an embedder enforce its own path policy.
+    PY_MAYBENULL bool (*open_file)(const char* path, const char* mode);
 } py_Callbacks;
 
 /// A struct contains the application-level callbacks.

run_tests.sh

@@ -17,7 +17,7 @@ rm -rf .coverage
 mkdir .coverage
 
 UNITS=$(find ./ -name "*.gcno")
-llvm-cov-17 gcov ${UNITS} -r -s include/ -r -s src/ >> .coverage/coverage.txt
+llvm-cov-19 gcov ${UNITS} -r -s include/ -r -s src/ >> .coverage/coverage.txt
 
 mv *.gcov .coverage
 rm *.gcda

src/compiler/lexer.c

@@ -189,8 +189,8 @@ static Error* LexerError(Lexer* self, const char* fmt, ...) {
     err->src = self->src;
     PK_INCREF(self->src);
     err->lineno = self->current_line;
-    const char* end = self->src->source->data + self->src->source->size;
+    const char* p_end = self->src->source->data + self->src->source->size;
-    if(self->curr_char <= end && *self->curr_char == '\n') { err->lineno--; }
+    if(self->curr_char <= p_end && *self->curr_char == '\n') { err->lineno--; }
     va_list args;
     va_start(args, fmt);
     vsnprintf(err->msg, sizeof(err->msg), fmt, args);
@@ -282,9 +282,16 @@ static Error* _eat_string(Lexer* self, c11_sbuf* buff, char quote, enum StringTy
                 case 'b': c11_sbuf__write_char(buff, '\b'); break;
                 case 'f': c11_sbuf__write_char(buff, '\f'); break;
                 case 'v': c11_sbuf__write_char(buff, '\v'); break;
-                // Special case for the often used \0 while we don't have full support for octal literals.
+                // Special case for the often used \0 while we don't have full support for octal
+                // literals.
                 case '0': c11_sbuf__write_char(buff, '\0'); break;
                 case 'x': {
+                    // check there are at least 2 chars can read
+                    const char* p_end = self->src->source->data + self->src->source->size;
+                    if(p_end - self->curr_char < 2) {
+                        return LexerError(self, "invalid hex escape");
+                    }
+
                     char hex[3] = {eatchar(self), eatchar(self), '\0'};
                     int code;
                     if(sscanf(hex, "%x", &code) != 1 || code > 0xFF) {

src/interpreter/vm.c

@@ -92,6 +92,7 @@ void VM__ctor(VM* self) {
     self->callbacks.print = pk_default_print;
     self->callbacks.flush = pk_default_flush;
     self->callbacks.getchr = pk_default_getchr;
+    self->callbacks.open_file = NULL;
 
     self->last_retval = *py_NIL();
     self->unhandled_exc = *py_NIL();
@@ -579,8 +580,9 @@ FrameResult VM__vectorcall(VM* self, uint16_t argc, uint16_t kwargc, bool opcall
     }
 
     if(p0->type == tp_type) {
+        py_Type p0_type = py_totype(p0);
         // [cls, NULL, args..., kwargs...]
-        py_Ref new_f = py_tpfindmagic(py_totype(p0), __new__);
+        py_Ref new_f = py_tpfindmagic(p0_type, __new__);
         assert(new_f && py_isnil(p0 + 1));
         bool is_default_new = new_f->type == tp_nativefunc && new_f->_cfunc == pk__object_new;
 
@@ -598,14 +600,16 @@ FrameResult VM__vectorcall(VM* self, uint16_t argc, uint16_t kwargc, bool opcall
         // NOTE: previously we use `get_unbound_method` but here we just use `tpfindmagic`
         // >> [cls, NULL, args..., kwargs...]
         // >> py_retval() is the new instance
-        py_Ref init_f = py_tpfindmagic(py_totype(p0), __init__);
+        py_Ref init_f = py_tpfindmagic(p0_type, __init__);
         if(init_f) {
+            if(py_isinstance(py_retval(), p0_type)) {
                 // do an inplace patch
                 *p0 = *init_f;              // __init__
                 p0[1] = self->last_retval;  // self
                 // [__init__, self, args..., kwargs...]
                 if(VM__vectorcall(self, argc, kwargc, false) == RES_ERROR) return RES_ERROR;
                 *py_retval() = p0[1];  // restore the new instance
+            }
         } else {
             if(is_default_new) {
                 if(argc != 0 || kwargc != 0) {
@@ -713,8 +717,16 @@ void ManagedHeap__mark(ManagedHeap* self) {
             }
         }
 
+        if(obj->type > tp_object) {
+            // NOTE: `defaultdict` -> `dict` -> `object`
+            // NOTE: native types must extend from `object`.
+            py_TypeInfo* ti = pk_typeinfo(obj->type);
+            while(ti->base != tp_object) {
+                ti = ti->base_ti;
+            }
+
             void* ud = PyObject__userdata(obj);
-        switch(obj->type) {
+            switch(ti->index) {
                 case tp_list: {
                     List* self = ud;
                     for(int i = 0; i < self->length; i++) {
@@ -763,4 +775,5 @@ void ManagedHeap__mark(ManagedHeap* self) {
                 }
             }
         }
+    }
 }

src/modules/os.c

@@ -71,6 +71,10 @@ static bool os_remove(int argc, py_Ref argv) {
     PY_CHECK_ARGC(1);
     PY_CHECK_ARG_TYPE(0, tp_str);
     const char* path = py_tostr(py_arg(0));
+    // open_file policy hook: "delete" pseudo-mode for os.remove.
+    if(pk_current_vm->callbacks.open_file && !pk_current_vm->callbacks.open_file(path, "delete")) {
+        return OSError("os.remove not permitted: '%s'", path);
+    }
     int code = remove(path);
     if(code != 0) {
         const char* msg = strerror(errno);
@@ -111,6 +115,11 @@ static bool io_FileIO__new__(int argc, py_Ref argv) {
     io_FileIO* ud = py_newobject(py_retval(), cls, 0, sizeof(io_FileIO));
     ud->path = py_tostr(py_arg(1));
     ud->mode = py_tostr(py_arg(2));
+    // open_file policy hook: consulted with the fopen mode string before the open.
+    if(pk_current_vm->callbacks.open_file &&
+       !pk_current_vm->callbacks.open_file(ud->path, ud->mode)) {
+        return OSError("file open not permitted: '%s' (mode '%s')", ud->path, ud->mode);
+    }
     ud->file = fopen(ud->path, ud->mode);
     if(ud->file == NULL) {
         const char* msg = strerror(errno);

src/public/GlobalSetup.c

@@ -5,7 +5,7 @@
 #include "pocketpy/common/name.h"
 #include "pocketpy/interpreter/vm.h"
 
-_Thread_local VM* pk_current_vm;
+PK_THREAD_LOCAL VM* pk_current_vm;
 
 static bool pk_initialized;
 static bool pk_finalized;

tests/410_class_ex.py

@@ -168,3 +168,13 @@ class DerivedClass(BaseClass):
 
     
 assert DerivedClass.f() == 'BaseClass'
+
+# bad __init__
+class A:
+    def __new__(cls, *args, **kwargs):
+        return 1
+
+    def __init__(self):
+        assert False
+
+A()