bpo-40302: Add pycore_byteswap.h header file (GH-19552)
Add a new internal pycore_byteswap.h header file with the following
functions:
* _Py_bswap16()
* _Py_bswap32()
* _Py_bswap64()
Use these functions in _ctypes, sha256 and sha512 modules,
and also use in the UTF-32 encoder.
sha256, sha512 and _ctypes modules are now built with the internal
C API.
diff --git a/Modules/Setup b/Modules/Setup
index 40266a1..9dcca13 100644
--- a/Modules/Setup
+++ b/Modules/Setup
@@ -247,8 +247,8 @@
# The _sha module implements the SHA checksum algorithms.
# (NIST's Secure Hash Algorithms.)
#_sha1 sha1module.c
-#_sha256 sha256module.c
-#_sha512 sha512module.c
+#_sha256 sha256module.c -DPy_BUILD_CORE_BUILTIN
+#_sha512 sha512module.c -DPy_BUILD_CORE_BUILTIN
#_sha3 _sha3/sha3module.c
# _blake module
diff --git a/Modules/_ctypes/cfield.c b/Modules/_ctypes/cfield.c
index 2060d15..a72682d 100644
--- a/Modules/_ctypes/cfield.c
+++ b/Modules/_ctypes/cfield.c
@@ -1,4 +1,5 @@
#include "Python.h"
+#include "pycore_byteswap.h" // _Py_bswap32()
#include <ffi.h>
#ifdef MS_WIN32
@@ -448,46 +449,32 @@
( ( (type)x & ~(BIT_MASK(type, size) << LOW_BIT(size)) ) | ( ((type)v & BIT_MASK(type, size)) << LOW_BIT(size) ) ) \
: (type)v)
-/* byte swapping macros */
-#define SWAP_2(v) \
- ( ( (v >> 8) & 0x00FF) | \
- ( (v << 8) & 0xFF00) )
-
-#define SWAP_4(v) \
- ( ( (v & 0x000000FF) << 24 ) | \
- ( (v & 0x0000FF00) << 8 ) | \
- ( (v & 0x00FF0000) >> 8 ) | \
- ( ((v >> 24) & 0xFF)) )
-
-#ifdef _MSC_VER
-#define SWAP_8(v) \
- ( ( (v & 0x00000000000000FFL) << 56 ) | \
- ( (v & 0x000000000000FF00L) << 40 ) | \
- ( (v & 0x0000000000FF0000L) << 24 ) | \
- ( (v & 0x00000000FF000000L) << 8 ) | \
- ( (v & 0x000000FF00000000L) >> 8 ) | \
- ( (v & 0x0000FF0000000000L) >> 24 ) | \
- ( (v & 0x00FF000000000000L) >> 40 ) | \
- ( ((v >> 56) & 0xFF)) )
+#if SIZEOF_SHORT == 2
+# define SWAP_SHORT _Py_bswap16
#else
-#define SWAP_8(v) \
- ( ( (v & 0x00000000000000FFLL) << 56 ) | \
- ( (v & 0x000000000000FF00LL) << 40 ) | \
- ( (v & 0x0000000000FF0000LL) << 24 ) | \
- ( (v & 0x00000000FF000000LL) << 8 ) | \
- ( (v & 0x000000FF00000000LL) >> 8 ) | \
- ( (v & 0x0000FF0000000000LL) >> 24 ) | \
- ( (v & 0x00FF000000000000LL) >> 40 ) | \
- ( ((v >> 56) & 0xFF)) )
+# error "unsupported short size"
#endif
-#define SWAP_INT SWAP_4
+#if SIZEOF_INT == 4
+# define SWAP_INT _Py_bswap32
+#else
+# error "unsupported int size"
+#endif
#if SIZEOF_LONG == 4
-# define SWAP_LONG SWAP_4
+# define SWAP_LONG _Py_bswap32
#elif SIZEOF_LONG == 8
-# define SWAP_LONG SWAP_8
+# define SWAP_LONG _Py_bswap64
+#else
+# error "unsupported long size"
#endif
+
+#if SIZEOF_LONG_LONG == 8
+# define SWAP_LONG_LONG _Py_bswap64
+#else
+# error "unsupported long long size"
+#endif
+
/*****************************************************************
* The setter methods return an object which must be kept alive, to keep the
* data valid which has been stored in the memory block. The ctypes object
@@ -569,12 +556,13 @@
{
long val;
short field;
- if (get_long(value, &val) < 0)
+ if (get_long(value, &val) < 0) {
return NULL;
+ }
memcpy(&field, ptr, sizeof(field));
- field = SWAP_2(field);
+ field = SWAP_SHORT(field);
field = SET(short, field, val, size);
- field = SWAP_2(field);
+ field = SWAP_SHORT(field);
memcpy(ptr, &field, sizeof(field));
_RET(value);
}
@@ -593,7 +581,7 @@
{
short val;
memcpy(&val, ptr, sizeof(val));
- val = SWAP_2(val);
+ val = SWAP_SHORT(val);
GET_BITFIELD(val, size);
return PyLong_FromLong(val);
}
@@ -616,12 +604,13 @@
{
unsigned long val;
unsigned short field;
- if (get_ulong(value, &val) < 0)
+ if (get_ulong(value, &val) < 0) {
return NULL;
+ }
memcpy(&field, ptr, sizeof(field));
- field = SWAP_2(field);
+ field = SWAP_SHORT(field);
field = SET(unsigned short, field, val, size);
- field = SWAP_2(field);
+ field = SWAP_SHORT(field);
memcpy(ptr, &field, sizeof(field));
_RET(value);
}
@@ -641,7 +630,7 @@
{
unsigned short val;
memcpy(&val, ptr, sizeof(val));
- val = SWAP_2(val);
+ val = SWAP_SHORT(val);
GET_BITFIELD(val, size);
return PyLong_FromLong(val);
}
@@ -664,8 +653,9 @@
{
long val;
int field;
- if (get_long(value, &val) < 0)
+ if (get_long(value, &val) < 0) {
return NULL;
+ }
memcpy(&field, ptr, sizeof(field));
field = SWAP_INT(field);
field = SET(int, field, val, size);
@@ -757,8 +747,9 @@
{
unsigned long val;
unsigned int field;
- if (get_ulong(value, &val) < 0)
+ if (get_ulong(value, &val) < 0) {
return NULL;
+ }
memcpy(&field, ptr, sizeof(field));
field = SWAP_INT(field);
field = SET(unsigned int, field, (unsigned int)val, size);
@@ -805,8 +796,9 @@
{
long val;
long field;
- if (get_long(value, &val) < 0)
+ if (get_long(value, &val) < 0) {
return NULL;
+ }
memcpy(&field, ptr, sizeof(field));
field = SWAP_LONG(field);
field = SET(long, field, val, size);
@@ -853,8 +845,9 @@
{
unsigned long val;
unsigned long field;
- if (get_ulong(value, &val) < 0)
+ if (get_ulong(value, &val) < 0) {
return NULL;
+ }
memcpy(&field, ptr, sizeof(field));
field = SWAP_LONG(field);
field = SET(unsigned long, field, val, size);
@@ -901,12 +894,13 @@
{
long long val;
long long field;
- if (get_longlong(value, &val) < 0)
+ if (get_longlong(value, &val) < 0) {
return NULL;
+ }
memcpy(&field, ptr, sizeof(field));
- field = SWAP_8(field);
+ field = SWAP_LONG_LONG(field);
field = SET(long long, field, val, size);
- field = SWAP_8(field);
+ field = SWAP_LONG_LONG(field);
memcpy(ptr, &field, sizeof(field));
_RET(value);
}
@@ -925,7 +919,7 @@
{
long long val;
memcpy(&val, ptr, sizeof(val));
- val = SWAP_8(val);
+ val = SWAP_LONG_LONG(val);
GET_BITFIELD(val, size);
return PyLong_FromLongLong(val);
}
@@ -948,12 +942,13 @@
{
unsigned long long val;
unsigned long long field;
- if (get_ulonglong(value, &val) < 0)
+ if (get_ulonglong(value, &val) < 0) {
return NULL;
+ }
memcpy(&field, ptr, sizeof(field));
- field = SWAP_8(field);
+ field = SWAP_LONG_LONG(field);
field = SET(unsigned long long, field, val, size);
- field = SWAP_8(field);
+ field = SWAP_LONG_LONG(field);
memcpy(ptr, &field, sizeof(field));
_RET(value);
}
@@ -972,7 +967,7 @@
{
unsigned long long val;
memcpy(&val, ptr, sizeof(val));
- val = SWAP_8(val);
+ val = SWAP_LONG_LONG(val);
GET_BITFIELD(val, size);
return PyLong_FromUnsignedLongLong(val);
}
diff --git a/Modules/_testinternalcapi.c b/Modules/_testinternalcapi.c
index 8352f6e..9330e26 100644
--- a/Modules/_testinternalcapi.c
+++ b/Modules/_testinternalcapi.c
@@ -9,6 +9,7 @@
#define PY_SSIZE_T_CLEAN
#include "Python.h"
+#include "pycore_byteswap.h" // _Py_bswap32()
#include "pycore_initconfig.h" // _Py_GetConfigsAsDict()
#include "pycore_gc.h" // PyGC_Head
@@ -21,7 +22,7 @@
static PyObject*
-get_recursion_depth(PyObject *self, PyObject *args)
+get_recursion_depth(PyObject *self, PyObject *Py_UNUSED(args))
{
PyThreadState *tstate = PyThreadState_Get();
@@ -30,9 +31,38 @@
}
+static PyObject*
+test_bswap(PyObject *self, PyObject *Py_UNUSED(args))
+{
+ uint16_t u16 = _Py_bswap16(UINT16_C(0x3412));
+ if (u16 != UINT16_C(0x1234)) {
+ PyErr_Format(PyExc_AssertionError,
+ "_Py_bswap16(0x3412) returns %u", u16);
+ return NULL;
+ }
+
+ uint32_t u32 = _Py_bswap32(UINT32_C(0x78563412));
+ if (u32 != UINT32_C(0x12345678)) {
+ PyErr_Format(PyExc_AssertionError,
+ "_Py_bswap32(0x78563412) returns %lu", u32);
+ return NULL;
+ }
+
+ uint64_t u64 = _Py_bswap64(UINT64_C(0xEFCDAB9078563412));
+ if (u64 != UINT64_C(0x1234567890ABCDEF)) {
+ PyErr_Format(PyExc_AssertionError,
+ "_Py_bswap64(0xEFCDAB9078563412) returns %llu", u64);
+ return NULL;
+ }
+
+ Py_RETURN_NONE;
+}
+
+
static PyMethodDef TestMethods[] = {
{"get_configs", get_configs, METH_NOARGS},
{"get_recursion_depth", get_recursion_depth, METH_NOARGS},
+ {"test_bswap", test_bswap, METH_NOARGS},
{NULL, NULL} /* sentinel */
};
diff --git a/Modules/sha256module.c b/Modules/sha256module.c
index 7310826..e0ff9b2 100644
--- a/Modules/sha256module.c
+++ b/Modules/sha256module.c
@@ -17,6 +17,7 @@
/* SHA objects */
#include "Python.h"
+#include "pycore_byteswap.h" // _Py_bswap32()
#include "structmember.h" // PyMemberDef
#include "hashlib.h"
#include "pystrhex.h"
@@ -30,12 +31,7 @@
/* Some useful types */
typedef unsigned char SHA_BYTE;
-
-#if SIZEOF_INT == 4
-typedef unsigned int SHA_INT32; /* 32-bit integer */
-#else
-/* not defined. compilation will die. */
-#endif
+typedef uint32_t SHA_INT32; /* 32-bit integer */
/* The SHA block size and message digest sizes, in bytes */
@@ -61,14 +57,9 @@
#if PY_LITTLE_ENDIAN
static void longReverse(SHA_INT32 *buffer, int byteCount)
{
- SHA_INT32 value;
-
byteCount /= sizeof(*buffer);
- while (byteCount--) {
- value = *buffer;
- value = ( ( value & 0xFF00FF00L ) >> 8 ) | \
- ( ( value & 0x00FF00FFL ) << 8 );
- *buffer++ = ( value << 16 ) | ( value >> 16 );
+ for (; byteCount--; buffer++) {
+ *buffer = _Py_bswap32(*buffer);
}
}
#endif
diff --git a/Modules/sha512module.c b/Modules/sha512module.c
index 38d303d..780f8e7 100644
--- a/Modules/sha512module.c
+++ b/Modules/sha512module.c
@@ -17,6 +17,7 @@
/* SHA objects */
#include "Python.h"
+#include "pycore_byteswap.h" // _Py_bswap32()
#include "structmember.h" // PyMemberDef
#include "hashlib.h"
#include "pystrhex.h"
@@ -30,13 +31,8 @@
/* Some useful types */
typedef unsigned char SHA_BYTE;
-
-#if SIZEOF_INT == 4
-typedef unsigned int SHA_INT32; /* 32-bit integer */
-typedef unsigned long long SHA_INT64; /* 64-bit integer */
-#else
-/* not defined. compilation will die. */
-#endif
+typedef uint32_t SHA_INT32; /* 32-bit integer */
+typedef uint64_t SHA_INT64; /* 64-bit integer */
/* The SHA block size and message digest sizes, in bytes */
@@ -62,22 +58,9 @@
#if PY_LITTLE_ENDIAN
static void longReverse(SHA_INT64 *buffer, int byteCount)
{
- SHA_INT64 value;
-
byteCount /= sizeof(*buffer);
- while (byteCount--) {
- value = *buffer;
-
- ((unsigned char*)buffer)[0] = (unsigned char)(value >> 56) & 0xff;
- ((unsigned char*)buffer)[1] = (unsigned char)(value >> 48) & 0xff;
- ((unsigned char*)buffer)[2] = (unsigned char)(value >> 40) & 0xff;
- ((unsigned char*)buffer)[3] = (unsigned char)(value >> 32) & 0xff;
- ((unsigned char*)buffer)[4] = (unsigned char)(value >> 24) & 0xff;
- ((unsigned char*)buffer)[5] = (unsigned char)(value >> 16) & 0xff;
- ((unsigned char*)buffer)[6] = (unsigned char)(value >> 8) & 0xff;
- ((unsigned char*)buffer)[7] = (unsigned char)(value ) & 0xff;
-
- buffer++;
+ for (; byteCount--; buffer++) {
+ *buffer = _Py_bswap64(*buffer);
}
}
#endif