DRYer

setup/extensions.json

@@ -116,6 +116,7 @@
     },
     {
         "name": "fast_css_transform",
+        "headers": "calibre/utils/cpp_binding.h",
         "sources": "calibre/srv/fast_css_transform.cpp",
 		"inc_dirs": "perfect-hashing",
 		"needs_c++14": true
@@ -145,7 +146,7 @@
     {
         "name": "winutil",
         "only": "windows",
-        "headers": "calibre/utils/windows/common.h",
+        "headers": "calibre/utils/cpp_binding.h calibre/utils/windows/common.h",
         "sources": "calibre/utils/windows/winutil.cpp",
         "libraries": "shell32 wininet advapi32",
         "cflags": "/X"
@@ -153,7 +154,7 @@
     {
         "name": "winsapi",
         "only": "windows",
-        "headers": "calibre/utils/windows/common.h",
+        "headers": "calibre/utils/cpp_binding.h calibre/utils/windows/common.h",
         "sources": "calibre/utils/windows/winsapi.cpp",
         "libraries": "SAPI Ole32",
         "cflags": "/X"
@@ -162,7 +163,7 @@
         "name": "wpd",
         "only": "windows",
         "sources": "calibre/devices/mtp/windows/utils.cpp calibre/devices/mtp/windows/device_enumeration.cpp calibre/devices/mtp/windows/content_enumeration.cpp calibre/devices/mtp/windows/device.cpp calibre/devices/mtp/windows/wpd.cpp",
-        "headers": "calibre/devices/mtp/windows/global.h calibre/utils/windows/common.h",
+        "headers": "calibre/utils/cpp_binding.h calibre/devices/mtp/windows/global.h calibre/utils/windows/common.h",
         "libraries": "ole32 oleaut32 portabledeviceguids user32",
         "cflags": "/X"
     },

src/calibre/devices/mtp/windows/device_enumeration.cpp

@@ -127,7 +127,7 @@ get_storage_info(IPortableDevice *device) { // {{{
         Py_END_ALLOW_THREADS;
         if (SUCCEEDED(hr)) {
 			com_wchar_raii cleanup[arraysz(object_ids)];
-            for (i = 0; i < arraysz(object_ids); i++) { cleanup[i].set_ptr(object_ids[i]); };
+            for (i = 0; i < arraysz(object_ids); i++) { cleanup[i].attach(object_ids[i]); };
             for(i = 0; i < fetched; i++) {
 				CComPtr<IPortableDeviceValues> values;
                 Py_BEGIN_ALLOW_THREADS;

src/calibre/srv/fast_css_transform.cpp

@@ -24,6 +24,7 @@
 #include <codecvt>
 #include <frozen/unordered_map.h>
 #include <frozen/string.h>
+#include "../utils/cpp_binding.h"
 
 // character classes {{{
 static inline bool
@@ -78,25 +79,6 @@ class python_error : public std::runtime_error {
 		python_error(const char *msg) : std::runtime_error(msg) {}
 };
 
-class pyobject_raii {
-	private:
-		PyObject *handle;
-		pyobject_raii( const pyobject_raii & ) ;
-		pyobject_raii & operator=( const pyobject_raii & ) ;
-
-	public:
-		pyobject_raii() : handle(NULL) {}
-		pyobject_raii(PyObject* h, bool incref=false) : handle(h) { if (incref && handle) Py_INCREF(handle); }
-
-		~pyobject_raii() { Py_CLEAR(handle); }
-
-		PyObject *ptr() { return handle; }
-		void set_ptr(PyObject *val) { handle = val; }
-		PyObject **address() { return &handle; }
-		explicit operator bool() const { return handle != NULL; }
-        PyObject *detach() { PyObject *ans = handle; handle = NULL; return ans; }
-};
-
 // Parse numbers {{{
 
 typedef long long integer_type;
@@ -670,9 +652,10 @@ class TokenQueue {
 		}
 
     public:
-        TokenQueue(const size_t src_sz, PyObject *url_callback=NULL) :
+        TokenQueue(const size_t src_sz, PyObject *url_callback_pointer=NULL) :
-			pool(), queue(), out(), scratch(), scratch2(), url_callback(url_callback, true) {
+			pool(), queue(), out(), scratch(), scratch2(), url_callback(url_callback_pointer) {
 				out.reserve(src_sz * 2); scratch.reserve(16); scratch2.reserve(16);
+				Py_XINCREF(url_callback.ptr());
 			}
 
 		void rewind_output() { out.pop_back(); }

src/calibre/utils/cpp_binding.h

@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2021 Kovid Goyal <kovid at kovidgoyal.net>
+ *
+ * Distributed under terms of the GPL3 license.
+ */
+
+#pragma once
+
+#define PY_SSIZE_T_CLEAN
+#define UNICODE
+#define _UNICODE
+#include <Python.h>
+#include <wchar.h>
+
+#define arraysz(x) (sizeof(x)/sizeof(x[0]))
+
+template<typename T, void free_T(void*), T null=reinterpret_cast<T>(NULL)>
+class generic_raii {
+	private:
+		T handle;
+		generic_raii( const generic_raii & ) ;
+		generic_raii & operator=( const generic_raii & ) ;
+
+	public:
+		explicit generic_raii(T h = null) : handle(h) {}
+		~generic_raii() { release(); }
+
+		void release() {
+			if (handle != null) {
+				free_T(handle);
+				handle = null;
+			}
+		}
+
+		T ptr() { return handle; }
+		T detach() { T ans = handle; handle = null; return ans; }
+		void attach(T val) { release(); handle = val; }
+		T* address() { return &handle; }
+		explicit operator bool() const { return handle != null; }
+		T* operator &() { return &handle; }
+};
+
+typedef generic_raii<wchar_t*, PyMem_Free> wchar_raii;
+static inline void python_object_destructor(void *p) { PyObject *x = reinterpret_cast<PyObject*>(p); Py_XDECREF(x); }
+typedef generic_raii<PyObject*, python_object_destructor> pyobject_raii;
+
+
+static inline int
+py_to_wchar(PyObject *obj, wchar_raii *output) {
+	if (!PyUnicode_Check(obj)) {
+		if (obj == Py_None) { return 1; }
+		PyErr_SetString(PyExc_TypeError, "unicode object expected");
+		return 0;
+	}
+    wchar_t *buf = PyUnicode_AsWideCharString(obj, NULL);
+    if (!buf) { PyErr_NoMemory(); return 0; }
+	output->attach(buf);
+	return 1;
+}
+
+static inline int
+py_to_wchar_no_none(PyObject *obj, wchar_raii *output) {
+	if (!PyUnicode_Check(obj)) {
+		PyErr_SetString(PyExc_TypeError, "unicode object expected");
+		return 0;
+	}
+    wchar_t *buf = PyUnicode_AsWideCharString(obj, NULL);
+    if (!buf) { PyErr_NoMemory(); return 0; }
+	output->attach(buf);
+	return 1;
+}

src/calibre/utils/windows/common.h

@@ -11,7 +11,7 @@
 #include <Windows.h>
 #include <Python.h>
 #include <comdef.h>
-#define arraysz(x) (sizeof(x)/sizeof(x[0]))
+#include "../cpp_binding.h"
 
 static inline PyObject*
 set_error_from_hresult(PyObject *exc_type, const char *file, const int line, const HRESULT hr, const char *prefix="", PyObject *name=NULL) {
@@ -24,61 +24,6 @@ set_error_from_hresult(PyObject *exc_type, const char *file, const int line, con
 }
 #define error_from_hresult(hr, ...) set_error_from_hresult(PyExc_OSError, __FILE__, __LINE__, hr, __VA_ARGS__)
 
-template<typename T, void free_T(void*), T null>
-class generic_raii {
-	private:
-		T handle;
-		generic_raii( const generic_raii & ) ;
-		generic_raii & operator=( const generic_raii & ) ;
-
-	public:
-		explicit generic_raii(T h = null) : handle(h) {}
-		~generic_raii() { release(); }
-
-		void release() {
-			if (handle != null) {
-				free_T(handle);
-				handle = null;
-			}
-		}
-
-		T ptr() { return handle; }
-		T detach() { T ans = handle; handle = null; return ans; }
-		void set_ptr(T val) { handle = val; }
-		T* address() { return &handle; }
-		explicit operator bool() const { return handle != null; }
-		T* operator &() { return &handle; }
-};
-
-typedef generic_raii<wchar_t*, PyMem_Free, NULL> wchar_raii;
 typedef generic_raii<wchar_t*, CoTaskMemFree, NULL> com_wchar_raii;
-static inline void python_object_destructor(void *p) { PyObject *x = reinterpret_cast<PyObject*>(p); Py_XDECREF(x); }
-typedef generic_raii<PyObject*, python_object_destructor, NULL> pyobject_raii;
 static inline void handle_destructor(HANDLE p) { CloseHandle(p); }
 typedef generic_raii<HANDLE, handle_destructor, INVALID_HANDLE_VALUE> handle_raii;
-
-
-static int
-py_to_wchar(PyObject *obj, wchar_raii *output) {
-	if (!PyUnicode_Check(obj)) {
-		if (obj == Py_None) { return 1; }
-		PyErr_SetString(PyExc_TypeError, "unicode object expected");
-		return 0;
-	}
-    wchar_t *buf = PyUnicode_AsWideCharString(obj, NULL);
-    if (!buf) { PyErr_NoMemory(); return 0; }
-	output->set_ptr(buf);
-	return 1;
-}
-
-static int
-py_to_wchar_no_none(PyObject *obj, wchar_raii *output) {
-	if (!PyUnicode_Check(obj)) {
-		PyErr_SetString(PyExc_TypeError, "unicode object expected");
-		return 0;
-	}
-    wchar_t *buf = PyUnicode_AsWideCharString(obj, NULL);
-    if (!buf) { PyErr_NoMemory(); return 0; }
-	output->set_ptr(buf);
-	return 1;
-}

src/calibre/utils/windows/winutil.cpp

@@ -832,8 +832,7 @@ get_long_path_name(PyObject *self, PyObject *args) {
     Py_END_ALLOW_THREADS
     if (needed_size >= current_size - 32) {
         current_size = needed_size + 32;
-        PyMem_Free(buf.ptr());
+        buf.attach((wchar_t*)PyMem_Malloc(current_size * sizeof(wchar_t)));
-        buf.set_ptr((wchar_t*)PyMem_Malloc(current_size * sizeof(wchar_t)));
         if (!buf) return PyErr_NoMemory();
         Py_BEGIN_ALLOW_THREADS
         needed_size = GetLongPathNameW(path.ptr(), buf.ptr(), current_size);