stop using c++

msgpack · methane · May 4, 2024 · May 4, 2024 · May 4, 2024 · May 4, 2024
commit 1203eb79a8c86d4fdf32588b2bca8a596955f0e0
diff --git a/Makefile b/Makefile
@@ -22,7 +22,7 @@ pyupgrade:
 
 .PHONY: cython
 cython:
-	cython --cplus msgpack/_cmsgpack.pyx
+	cython msgpack/_cmsgpack.pyx
 
 .PHONY: test
 test: cython

diff --git a/msgpack/_unpacker.pyx b/msgpack/_unpacker.pyx
@@ -35,7 +35,7 @@ cdef extern from "unpack.h":
         PyObject* timestamp_t
         PyObject *giga;
         PyObject *utc;
-        char *unicode_errors
+        const char *unicode_errors
         Py_ssize_t max_str_len
         Py_ssize_t max_bin_len
         Py_ssize_t max_array_len

diff --git a/msgpack/unpack_container_header.h b/msgpack/unpack_container_header.h
@@ -0,0 +1,51 @@
+static inline int unpack_container_header(unpack_context* ctx, const char* data, Py_ssize_t len, Py_ssize_t* off)
+{
+    assert(len >= *off);
+    uint32_t size;
+    const unsigned char *const p = (unsigned char*)data + *off;
+
+#define inc_offset(inc) \
+    if (len - *off < inc) \
+        return 0; \
+    *off += inc;
+
+    switch (*p) {
+    case var_offset:
+        inc_offset(3);
+        size = _msgpack_load16(uint16_t, p + 1);
+        break;
+    case var_offset + 1:
+        inc_offset(5);
+        size = _msgpack_load32(uint32_t, p + 1);
+        break;
+#ifdef USE_CASE_RANGE
+    case fixed_offset + 0x0 ... fixed_offset + 0xf:
+#else
+    case fixed_offset + 0x0:
+    case fixed_offset + 0x1:
+    case fixed_offset + 0x2:
+    case fixed_offset + 0x3:
+    case fixed_offset + 0x4:
+    case fixed_offset + 0x5:
+    case fixed_offset + 0x6:
+    case fixed_offset + 0x7:
+    case fixed_offset + 0x8:
+    case fixed_offset + 0x9:
+    case fixed_offset + 0xa:
+    case fixed_offset + 0xb:
+    case fixed_offset + 0xc:
+    case fixed_offset + 0xd:
+    case fixed_offset + 0xe:
+    case fixed_offset + 0xf:
+#endif
+        ++*off;
+        size = ((unsigned int)*p) & 0x0f;
+        break;
+    default:
+        PyErr_SetString(PyExc_ValueError, "Unexpected type header on stream");
+        return -1;
+    }
+    unpack_callback_uint32(&ctx->user, size, &ctx->stack[0].obj);
+    return 1;
+}
+
diff --git a/msgpack/unpack_template.h b/msgpack/unpack_template.h
@@ -75,8 +75,7 @@ static inline void unpack_clear(unpack_context *ctx)
     Py_CLEAR(ctx->stack[0].obj);
 }
 
-template <bool construct>
-static inline int unpack_execute(unpack_context* ctx, const char* data, Py_ssize_t len, Py_ssize_t* off)
+static inline int unpack_execute(bool construct, unpack_context* ctx, const char* data, Py_ssize_t len, Py_ssize_t* off)
 {
     assert(len >= *off);
 
@@ -386,6 +385,7 @@ static inline int unpack_execute(unpack_context* ctx, const char* data, Py_ssize
 #undef construct_cb
 }
 
+#undef NEXT_CS
 #undef SWITCH_RANGE_BEGIN
 #undef SWITCH_RANGE
 #undef SWITCH_RANGE_DEFAULT
@@ -397,68 +397,27 @@ static inline int unpack_execute(unpack_context* ctx, const char* data, Py_ssize
 #undef again_fixed_trail_if_zero
 #undef start_container
 
-template <unsigned int fixed_offset, unsigned int var_offset>
-static inline int unpack_container_header(unpack_context* ctx, const char* data, Py_ssize_t len, Py_ssize_t* off)
-{
-    assert(len >= *off);
-    uint32_t size;
-    const unsigned char *const p = (unsigned char*)data + *off;
-
-#define inc_offset(inc) \
-    if (len - *off < inc) \
-        return 0; \
-    *off += inc;
-
-    switch (*p) {
-    case var_offset:
-        inc_offset(3);
-        size = _msgpack_load16(uint16_t, p + 1);
-        break;
-    case var_offset + 1:
-        inc_offset(5);
-        size = _msgpack_load32(uint32_t, p + 1);
-        break;
-#ifdef USE_CASE_RANGE
-    case fixed_offset + 0x0 ... fixed_offset + 0xf:
-#else
-    case fixed_offset + 0x0:
-    case fixed_offset + 0x1:
-    case fixed_offset + 0x2:
-    case fixed_offset + 0x3:
-    case fixed_offset + 0x4:
-    case fixed_offset + 0x5:
-    case fixed_offset + 0x6:
-    case fixed_offset + 0x7:
-    case fixed_offset + 0x8:
-    case fixed_offset + 0x9:
-    case fixed_offset + 0xa:
-    case fixed_offset + 0xb:
-    case fixed_offset + 0xc:
-    case fixed_offset + 0xd:
-    case fixed_offset + 0xe:
-    case fixed_offset + 0xf:
-#endif
-        ++*off;
-        size = ((unsigned int)*p) & 0x0f;
-        break;
-    default:
-        PyErr_SetString(PyExc_ValueError, "Unexpected type header on stream");
-        return -1;
-    }
-    unpack_callback_uint32(&ctx->user, size, &ctx->stack[0].obj);
-    return 1;
+static int unpack_construct(unpack_context *ctx, const char *data, Py_ssize_t len, Py_ssize_t *off) {
+    return unpack_execute(true, ctx, data, len, off);
+}
+static int unpack_skip(unpack_context *ctx, const char *data, Py_ssize_t len, Py_ssize_t *off) {
+    return unpack_execute(false, ctx, data, len, off);
 }
 
-#undef SWITCH_RANGE_BEGIN
-#undef SWITCH_RANGE
-#undef SWITCH_RANGE_DEFAULT
-#undef SWITCH_RANGE_END
-
-static const execute_fn unpack_construct = &unpack_execute<true>;
-static const execute_fn unpack_skip = &unpack_execute<false>;
-static const execute_fn read_array_header = &unpack_container_header<0x90, 0xdc>;
-static const execute_fn read_map_header = &unpack_container_header<0x80, 0xde>;
-
-#undef NEXT_CS
+#define unpack_container_header read_array_header
+#define fixed_offset 0x90
+#define var_offset 0xdc
+#include "unpack_container_header.h"
+#undef unpack_container_header
+#undef fixed_offset
+#undef var_offset
+
+#define unpack_container_header read_map_header
+#define fixed_offset 0x80
+#define var_offset 0xde
+#include "unpack_container_header.h"
+#undef unpack_container_header
+#undef fixed_offset
+#undef var_offset
 
 /* vim: set ts=4 sw=4 sts=4 expandtab  */
diff --git a/setup.py b/setup.py
@@ -1,23 +1,6 @@
 #!/usr/bin/env python
 import os
 import sys
-
-
-libraries = []
-macros = []
-
-if sys.platform == "win32":
-    libraries.append("ws2_32")
-    macros = [("__LITTLE_ENDIAN__", "1")]
-    cflags = os.environ.get("CXXFLAGS")
-    cxx20flag = "/std:c++20"
-    if cflags is None:
-        cflags = cxx20flag
-    elif cxx20flag not in cflags:
-        cflags += " " + cxx20flag
-    os.environ["CXXFLAGS"] = cflags
-
-
 from setuptools import setup, Extension
 from setuptools.command.build_ext import build_ext
 from setuptools.command.sdist import sdist
@@ -42,7 +25,7 @@ def cythonize(src):
     if not have_cython:
         raise Exception("Cython is required for building from checkout")
     sys.stderr.write(f"cythonize: {src!r}\n")
-    cython_compiler.compile([src], cplus=True)
+    cython_compiler.compile([src])
 
 
 def ensure_source(src):
@@ -66,12 +49,19 @@ def __init__(self, *args, **kwargs):
         sdist.__init__(self, *args, **kwargs)
 
 
+libraries = []
+macros = []
 ext_modules = []
+
+if sys.platform == "win32":
+    libraries.append("ws2_32")
+    macros = [("__LITTLE_ENDIAN__", "1")]
+
 if not PYPY and not os.environ.get("MSGPACK_PUREPYTHON"):
     ext_modules.append(
         Extension(
             "msgpack._cmsgpack",
-            sources=["msgpack/_cmsgpack.cpp"],
+            sources=["msgpack/_cmsgpack.c"],
             libraries=libraries,
             include_dirs=["."],
             define_macros=macros,