src/pl/plpython/plpython_system.h

/*-------------------------------------------------------------------------
 *
 * plpython_system.h - pull in Python's system header files
 *
 * We break this out as a separate header file to precisely control
 * the scope of the "system_header" pragma.  No Postgres-specific
 * declarations should be put here.  However, we do include some stuff
 * that is meant to prevent conflicts between our code and Python.
 *
 * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/pl/plpython/plpython_system.h
 *
 *-------------------------------------------------------------------------
 */
#ifndef PLPYTHON_SYSTEM_H
#define PLPYTHON_SYSTEM_H

/*
 * Newer versions of the Python headers trigger a lot of warnings with our
 * preferred compiler flags (at least -Wdeclaration-after-statement is known
 * to be problematic). The system_header pragma hides warnings from within
 * the rest of this file, if supported.
 */
#ifdef HAVE_PRAGMA_GCC_SYSTEM_HEADER
#pragma GCC system_header
#endif

/*
 * Undefine some things that get (re)defined in the Python headers. They aren't
 * used by the PL/Python code, and all PostgreSQL headers should be included
 * earlier, so this should be pretty safe.
 */
#undef _POSIX_C_SOURCE
#undef _XOPEN_SOURCE

/*
 * Sometimes python carefully scribbles on our *printf macros.
 * So we undefine them here and redefine them after it's done its dirty deed.
 */
#undef vsnprintf
#undef snprintf
#undef vsprintf
#undef sprintf
#undef vfprintf
#undef fprintf
#undef vprintf
#undef printf

#if defined(_MSC_VER) && defined(_DEBUG)
/* Python uses #pragma to bring in a non-default libpython on VC++ if
 * _DEBUG is defined */
#undef _DEBUG
/* Also hide away errcode, since we load Python.h before postgres.h */
#define errcode __msvc_errcode
#include <Python.h>
#undef errcode
#define _DEBUG
#elif defined (_MSC_VER)
#define errcode __msvc_errcode
#include <Python.h>
#undef errcode
#else
#include <Python.h>
#endif

/*
 * Python 2/3 strings/unicode/bytes handling.  Python 2 has strings
 * and unicode, Python 3 has strings, which are unicode on the C
 * level, and bytes.  The porting convention, which is similarly used
 * in Python 2.6, is that "Unicode" is always unicode, and "Bytes" are
 * bytes in Python 3 and strings in Python 2.  Since we keep
 * supporting Python 2 and its usual strings, we provide a
 * compatibility layer for Python 3 that when asked to convert a C
 * string to a Python string it converts the C string from the
 * PostgreSQL server encoding to a Python Unicode object.
 */
#if PY_MAJOR_VERSION >= 3
#define PyString_Check(x) 0
#define PyString_AsString(x) PLyUnicode_AsString(x)
#define PyString_FromString(x) PLyUnicode_FromString(x)
#define PyString_FromStringAndSize(x, size) PLyUnicode_FromStringAndSize(x, size)
#endif

/*
 * Python 3 only has long.
 */
#if PY_MAJOR_VERSION >= 3
#define PyInt_FromLong(x) PyLong_FromLong(x)
#define PyInt_AsLong(x) PyLong_AsLong(x)
#endif

/* Python 3 removed the Py_TPFLAGS_HAVE_ITER flag */
#if PY_MAJOR_VERSION >= 3
#define Py_TPFLAGS_HAVE_ITER 0
#endif

/* put back our *printf macros ... this must match src/include/port.h */
#ifdef vsnprintf
#undef vsnprintf
#endif
#ifdef snprintf
#undef snprintf
#endif
#ifdef vsprintf
#undef vsprintf
#endif
#ifdef sprintf
#undef sprintf
#endif
#ifdef vfprintf
#undef vfprintf
#endif
#ifdef fprintf
#undef fprintf
#endif
#ifdef vprintf
#undef vprintf
#endif
#ifdef printf
#undef printf
#endif

#define vsnprintf		pg_vsnprintf
#define snprintf		pg_snprintf
#define vsprintf		pg_vsprintf
#define sprintf			pg_sprintf
#define vfprintf		pg_vfprintf
#define fprintf			pg_fprintf
#define vprintf			pg_vprintf
#define printf(...)		pg_printf(__VA_ARGS__)

#endif							/* PLPYTHON_SYSTEM_H */