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3398 lines (3014 loc) · 96.3 KB
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#include "Python.h"
#include "pycore_fileutils.h" // fileutils definitions
#include "pycore_runtime.h" // _PyRuntime
#include "pycore_pystate.h" // _Py_AssertHoldsTstate()
#include "pycore_unicodeobject.h" // _Py_MAX_UNICODE
#include "osdefs.h" // SEP
#include <stdlib.h> // mbstowcs()
#ifdef HAVE_UNISTD_H
# include <unistd.h> // getcwd()
#endif
#ifdef MS_WINDOWS
# include <malloc.h>
# include <windows.h>
# include <winioctl.h> // FILE_DEVICE_* constants
# include "pycore_fileutils_windows.h" // FILE_STAT_BASIC_INFORMATION
# if defined(MS_WINDOWS_GAMES) && !defined(MS_WINDOWS_DESKTOP)
# define PATHCCH_ALLOW_LONG_PATHS 0x01
# else
# include <pathcch.h> // PathCchCombineEx
# endif
extern int winerror_to_errno(int);
#endif
#ifdef HAVE_LANGINFO_H
# include <langinfo.h> // nl_langinfo(CODESET)
#endif
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#ifdef HAVE_NON_UNICODE_WCHAR_T_REPRESENTATION
# include <iconv.h> // iconv_open()
#endif
#ifdef HAVE_FCNTL_H
# include <fcntl.h> // fcntl(F_GETFD)
#endif
#ifdef O_CLOEXEC
/* Does open() support the O_CLOEXEC flag? Possible values:
-1: unknown
0: open() ignores O_CLOEXEC flag, ex: Linux kernel older than 2.6.23
1: open() supports O_CLOEXEC flag, close-on-exec is set
The flag is used by _Py_open(), _Py_open_noraise(), io.FileIO
and os.open(). */
int _Py_open_cloexec_works = -1;
#endif
// wcstombs() error
static const size_t ENCODE_ERROR = (size_t)-1;
// mbstowcs() and mbrtowc() errors
static const size_t DECODE_ERROR = (size_t)-1;
#ifdef HAVE_MBRTOWC
static const size_t INCOMPLETE_CHARACTER = (size_t)-2;
#endif
// Get the error handler as 'int surrogateescape'.
// Set '*surrogateescape' and return 0 on success.
// Return -1 if the error handler is not supported: other than "strict" and
// "surrogateescape".
static int
get_surrogateescape(_Py_error_handler errors, int *surrogateescape)
{
switch (errors)
{
case _Py_ERROR_STRICT:
*surrogateescape = 0;
return 0;
case _Py_ERROR_SURROGATEESCAPE:
*surrogateescape = 1;
return 0;
default:
return -1;
}
}
PyObject *
_Py_device_encoding(int fd)
{
#if defined(MS_WINDOWS) && defined(HAVE_WINDOWS_CONSOLE_IO)
HANDLE handle;
DWORD temp;
UINT cp = 0;
_Py_BEGIN_SUPPRESS_IPH
handle = (HANDLE)_get_osfhandle(fd);
_Py_END_SUPPRESS_IPH
if (handle == INVALID_HANDLE_VALUE) {
Py_RETURN_NONE;
}
Py_BEGIN_ALLOW_THREADS
if (GetFileType(handle) == FILE_TYPE_CHAR) {
/* GetConsoleMode() only succeeds for a console handle. */
if (!GetConsoleMode(handle, &temp)) {
/* Assume that access denied implies an output handle. */
if (GetLastError() == ERROR_ACCESS_DENIED) {
cp = GetConsoleOutputCP();
}
}
else if (GetNumberOfConsoleInputEvents(handle, &temp)) {
cp = GetConsoleCP();
}
else {
cp = GetConsoleOutputCP();
}
}
Py_END_ALLOW_THREADS
/* GetConsoleCP() and GetConsoleOutputCP() return 0 if the application
has no console */
if (cp == CP_UTF8) {
_Py_DECLARE_STR(utf_8, "utf-8");
return &_Py_STR(utf_8);
}
if (cp == 0) {
Py_RETURN_NONE;
}
return PyUnicode_FromFormat("cp%u", (unsigned int)cp);
#else
int valid;
Py_BEGIN_ALLOW_THREADS
_Py_BEGIN_SUPPRESS_IPH
valid = isatty(fd);
_Py_END_SUPPRESS_IPH
Py_END_ALLOW_THREADS
if (!valid) {
Py_RETURN_NONE;
}
#ifdef MS_WINDOWS
Py_RETURN_NONE;
#else
if (_PyRuntime.preconfig.utf8_mode) {
_Py_DECLARE_STR(utf_8, "utf-8");
return &_Py_STR(utf_8);
}
return _Py_GetLocaleEncodingObject();
#endif
#endif /* MS_WINDOWS && HAVE_WINDOWS_CONSOLE_IO */
}
static int
is_valid_wide_char(wchar_t ch)
{
#ifdef HAVE_NON_UNICODE_WCHAR_T_REPRESENTATION
/* Oracle Solaris doesn't use Unicode code points as wchar_t encoding
for non-Unicode locales, which makes values higher than _Py_MAX_UNICODE
possibly valid. */
return 1;
#endif
if (Py_UNICODE_IS_SURROGATE(ch)) {
// Reject lone surrogate characters
return 0;
}
#if SIZEOF_WCHAR_T > 2
if (ch > _Py_MAX_UNICODE) {
// bpo-35883: Reject characters outside [U+0000; U+10ffff] range.
// The glibc mbstowcs() UTF-8 decoder does not respect the RFC 3629,
// it creates characters outside the [U+0000; U+10ffff] range:
// https://sourceware.org/bugzilla/show_bug.cgi?id=2373
return 0;
}
#endif
return 1;
}
static size_t
_Py_mbstowcs(wchar_t *dest, const char *src, size_t n)
{
size_t count = mbstowcs(dest, src, n);
if (dest != NULL && count != DECODE_ERROR) {
for (size_t i=0; i < count; i++) {
wchar_t ch = dest[i];
if (!is_valid_wide_char(ch)) {
return DECODE_ERROR;
}
}
}
return count;
}
#ifdef HAVE_MBRTOWC
static size_t
_Py_mbrtowc(wchar_t *pwc, const char *str, size_t len, mbstate_t *pmbs)
{
assert(pwc != NULL);
size_t count = mbrtowc(pwc, str, len, pmbs);
if (count != 0 && count != DECODE_ERROR && count != INCOMPLETE_CHARACTER) {
if (!is_valid_wide_char(*pwc)) {
return DECODE_ERROR;
}
}
return count;
}
#endif
#if !defined(_Py_FORCE_UTF8_FS_ENCODING) && !defined(MS_WINDOWS)
#define USE_FORCE_ASCII
extern int _Py_normalize_encoding(const char *, char *, size_t, int);
/* Workaround FreeBSD and OpenIndiana locale encoding issue with the C locale
and POSIX locale. nl_langinfo(CODESET) announces an alias of the
ASCII encoding, whereas mbstowcs() and wcstombs() functions use the
ISO-8859-1 encoding. The problem is that os.fsencode() and os.fsdecode() use
locale.getpreferredencoding() codec. For example, if command line arguments
are decoded by mbstowcs() and encoded back by os.fsencode(), we get a
UnicodeEncodeError instead of retrieving the original byte string.
The workaround is enabled if setlocale(LC_CTYPE, NULL) returns "C",
nl_langinfo(CODESET) announces "ascii" (or an alias to ASCII), and at least
one byte in range 0x80-0xff can be decoded from the locale encoding. The
workaround is also enabled on error, for example if getting the locale
failed.
On HP-UX with the C locale or the POSIX locale, nl_langinfo(CODESET)
announces "roman8" but mbstowcs() uses Latin1 in practice. Force also the
ASCII encoding in this case.
Values of force_ascii:
1: the workaround is used: Py_EncodeLocale() uses
encode_ascii() and Py_DecodeLocale() uses decode_ascii()
0: the workaround is not used: Py_EncodeLocale() uses wcstombs() and
Py_DecodeLocale() uses mbstowcs()
-1: unknown, need to call check_force_ascii() to get the value
*/
#define force_ascii (_PyRuntime.fileutils.force_ascii)
static int
check_force_ascii(void)
{
char *loc = setlocale(LC_CTYPE, NULL);
if (loc == NULL) {
goto error;
}
if (strcmp(loc, "C") != 0 && strcmp(loc, "POSIX") != 0) {
/* the LC_CTYPE locale is different than C and POSIX */
return 0;
}
#if defined(HAVE_LANGINFO_H) && defined(CODESET)
const char *codeset = nl_langinfo(CODESET);
if (!codeset || codeset[0] == '\0') {
/* CODESET is not set or empty */
goto error;
}
char encoding[20]; /* longest name: "iso_646.irv_1991\0" */
if (!_Py_normalize_encoding(codeset, encoding, sizeof(encoding), 1)) {
goto error;
}
#ifdef __hpux
if (strcmp(encoding, "roman8") == 0) {
unsigned char ch;
wchar_t wch;
size_t res;
ch = (unsigned char)0xA7;
res = _Py_mbstowcs(&wch, (char*)&ch, 1);
if (res != DECODE_ERROR && wch == L'\xA7') {
/* On HP-UX with C locale or the POSIX locale,
nl_langinfo(CODESET) announces "roman8", whereas mbstowcs() uses
Latin1 encoding in practice. Force ASCII in this case.
Roman8 decodes 0xA7 to U+00CF. Latin1 decodes 0xA7 to U+00A7. */
return 1;
}
}
#else
const char* ascii_aliases[] = {
"ascii",
/* Aliases from Lib/encodings/aliases.py */
"646",
"ansi_x3.4_1968",
"ansi_x3.4_1986",
"ansi_x3_4_1968",
"cp367",
"csascii",
"ibm367",
"iso646_us",
"iso_646.irv_1991",
"iso_ir_6",
"us",
"us_ascii",
NULL
};
int is_ascii = 0;
for (const char **alias=ascii_aliases; *alias != NULL; alias++) {
if (strcmp(encoding, *alias) == 0) {
is_ascii = 1;
break;
}
}
if (!is_ascii) {
/* nl_langinfo(CODESET) is not "ascii" or an alias of ASCII */
return 0;
}
for (unsigned int i=0x80; i<=0xff; i++) {
char ch[1];
wchar_t wch[1];
size_t res;
unsigned uch = (unsigned char)i;
ch[0] = (char)uch;
res = _Py_mbstowcs(wch, ch, 1);
if (res != DECODE_ERROR) {
/* decoding a non-ASCII character from the locale encoding succeed:
the locale encoding is not ASCII, force ASCII */
return 1;
}
}
/* None of the bytes in the range 0x80-0xff can be decoded from the locale
encoding: the locale encoding is really ASCII */
#endif /* !defined(__hpux) */
return 0;
#else
/* nl_langinfo(CODESET) is not available: always force ASCII */
return 1;
#endif /* defined(HAVE_LANGINFO_H) && defined(CODESET) */
error:
/* if an error occurred, force the ASCII encoding */
return 1;
}
int
_Py_GetForceASCII(void)
{
if (force_ascii == -1) {
force_ascii = check_force_ascii();
}
return force_ascii;
}
void
_Py_ResetForceASCII(void)
{
force_ascii = -1;
}
// Encode a wide string to the ASCII encoding. If errors is
// _Py_ERROR_SURROGATEESCAPE, handle non-ASCII character using the
// surrogateescape error handler. In that case, the output is non-ASCII.
//
// Set *str to a newly allocated string on success.
// Return a negative number on error: _Py_CODEC_MEMORY_ERROR,
// _Py_CODEC_ENCODE_ERROR or _Py_CODEC_UNSUPPORTED_ERROR_HANDLER.
//
// str and output_length must not be NULL
static int
encode_ascii(const wchar_t *text, char **str, size_t *output_length,
size_t *error_pos, int raw_malloc, _Py_error_handler errors)
{
assert(str != NULL);
assert(output_length != NULL);
int surrogateescape;
if (get_surrogateescape(errors, &surrogateescape) < 0) {
// Only support "strict" and "surrogateescape"
return _Py_CODEC_UNSUPPORTED_ERROR_HANDLER;
}
size_t len = wcslen(text);
*output_length = len;
/* +1 for NULL byte */
char *result;
result = raw_malloc ? PyMem_RawMalloc(len + 1) : PyMem_Malloc(len + 1);
if (result == NULL) {
return _Py_CODEC_MEMORY_ERROR;
}
char *out = result;
for (size_t i=0; i < len; i++) {
wchar_t ch = text[i];
if (ch <= 0x7f) {
/* ASCII character */
*out++ = (char)ch;
}
else if (surrogateescape && 0xdc80 <= ch && ch <= 0xdcff) {
/* UTF-8b surrogate */
*out++ = (char)(ch - 0xdc00);
}
else {
if (raw_malloc) {
PyMem_RawFree(result);
}
else {
PyMem_Free(result);
}
if (error_pos != NULL) {
*error_pos = i;
}
return _Py_CODEC_ENCODE_ERROR;
}
}
*out++ = '\0';
assert((size_t)(out - result) == (*output_length + 1));
*str = result;
return 0;
}
#else
int
_Py_GetForceASCII(void)
{
return 0;
}
void
_Py_ResetForceASCII(void)
{
/* nothing to do */
}
#endif /* defined(_Py_FORCE_UTF8_FS_ENCODING) || defined(MS_WINDOWS) */
#if !defined(HAVE_MBRTOWC) || defined(USE_FORCE_ASCII)
// Decode a bytes string from the ASCII encoding. If 'errors' is
// "surrogateescape", decode non-ASCII bytes with "surrogateescape" error
// handler and so the output is non-ASCII.
//
// On success, set *wstr and *wlen (if set) and return 0.
// On error, return a negative number: _Py_CODEC_MEMORY_ERROR,
// _Py_CODEC_DECODE_ERROR or _Py_CODEC_UNSUPPORTED_ERROR_HANDLER.
// On decode, set *wlen (if set).
static int
decode_ascii(const char *arg, wchar_t **wstr, size_t *wlen,
_Py_error_handler errors)
{
assert(arg != NULL);
assert(wstr != NULL);
wchar_t *res;
unsigned char *in;
wchar_t *out;
size_t argsize = strlen(arg) + 1;
int surrogateescape;
if (get_surrogateescape(errors, &surrogateescape) < 0) {
// Only support "strict" and "surrogateescape"
return _Py_CODEC_UNSUPPORTED_ERROR_HANDLER;
}
if (argsize > PY_SSIZE_T_MAX / sizeof(wchar_t)) {
return _Py_CODEC_MEMORY_ERROR;
}
res = PyMem_RawMalloc(argsize * sizeof(wchar_t));
if (!res) {
return _Py_CODEC_MEMORY_ERROR;
}
out = res;
for (in = (unsigned char*)arg; *in; in++) {
unsigned char ch = *in;
if (ch <= 127) {
*out++ = ch;
}
else {
if (!surrogateescape) {
PyMem_RawFree(res);
if (wlen) {
*wlen = in - (unsigned char*)arg;
}
return _Py_CODEC_DECODE_ERROR;
}
*out++ = 0xdc00 + ch;
}
}
*out = 0;
if (wlen != NULL) {
*wlen = out - res;
}
*wstr = res;
return 0;
}
#endif /* !HAVE_MBRTOWC */
// Decode a bytes string from the current locale encoding.
// On success, set *wstr and *wlen (if set) and return 0.
// On error, return a negative number: _Py_CODEC_MEMORY_ERROR,
// _Py_CODEC_DECODE_ERROR or _Py_CODEC_UNSUPPORTED_ERROR_HANDLER.
// On decode, set *wlen (if set).
static int
decode_current_locale(const char* arg, wchar_t **wstr, size_t *wlen,
_Py_error_handler errors)
{
assert(arg != NULL);
assert(wstr != NULL);
int surrogateescape;
if (get_surrogateescape(errors, &surrogateescape) < 0) {
// Only support "strict" and "surrogateescape"
return _Py_CODEC_UNSUPPORTED_ERROR_HANDLER;
}
#ifdef HAVE_BROKEN_MBSTOWCS
/* Some platforms have a broken implementation of
* mbstowcs which does not count the characters that
* would result from conversion. Use an upper bound.
*/
size_t argsize = strlen(arg);
#else
size_t argsize = _Py_mbstowcs(NULL, arg, 0);
#endif
wchar_t *res;
if (argsize != DECODE_ERROR) {
if (argsize > PY_SSIZE_T_MAX / sizeof(wchar_t) - 1) {
return _Py_CODEC_MEMORY_ERROR;
}
res = (wchar_t *)PyMem_RawMalloc((argsize + 1) * sizeof(wchar_t));
if (!res) {
return _Py_CODEC_MEMORY_ERROR;
}
// +1 to write also the trailing NUL character
size_t count = _Py_mbstowcs(res, arg, argsize + 1);
if (count != DECODE_ERROR) {
// String decoded successfully.
// gh-158893: This assertion can fail if the input string was
// mutated during this function call. For example, the assertion
// fails on decoding strerror() result if another thread mutated
// the string in-place by calling strerror() in parallel.
assert(count == argsize);
*wstr = res;
if (wlen != NULL) {
*wlen = count;
}
return 0;
}
PyMem_RawFree(res);
}
/* Conversion failed. Fall back to escaping with surrogateescape. */
#ifdef HAVE_MBRTOWC
/* Try conversion with mbrtwoc (C99), and escape non-decodable bytes. */
/* Overallocate; as multi-byte characters are in the argument, the
actual output could use less memory. */
argsize = strlen(arg) + 1;
if (argsize > PY_SSIZE_T_MAX / sizeof(wchar_t)) {
return _Py_CODEC_MEMORY_ERROR;
}
res = (wchar_t*)PyMem_RawMalloc(argsize * sizeof(wchar_t));
if (!res) {
return _Py_CODEC_MEMORY_ERROR;
}
unsigned char *in = (unsigned char*)arg;
wchar_t *out = res;
mbstate_t mbs;
memset(&mbs, 0, sizeof mbs);
while (argsize) {
size_t converted = _Py_mbrtowc(out, (char*)in, argsize, &mbs);
if (converted == 0) {
/* Reached end of string; null char stored. */
break;
}
if (converted == DECODE_ERROR || converted == INCOMPLETE_CHARACTER) {
if (!surrogateescape) {
goto decode_error;
}
/* Decoding error. Escape as UTF-8b, and start over in the initial
shift state. */
*out++ = 0xdc00 + *in++;
argsize--;
memset(&mbs, 0, sizeof mbs);
continue;
}
// _Py_mbrtowc() reject lone surrogate characters
assert(!Py_UNICODE_IS_SURROGATE(*out));
/* successfully converted some bytes */
in += converted;
argsize -= converted;
out++;
}
if (wlen != NULL) {
*wlen = out - res;
assert(res[*wlen] == 0);
}
*wstr = res;
return 0;
decode_error:
PyMem_RawFree(res);
if (wlen) {
*wlen = in - (unsigned char*)arg;
}
return _Py_CODEC_DECODE_ERROR;
#else /* HAVE_MBRTOWC */
/* Cannot use C locale for escaping; manually escape as if charset
is ASCII (i.e. escape all bytes > 128. This will still roundtrip
correctly in the locale's charset, which must be an ASCII superset. */
return decode_ascii(arg, wstr, wlen, errors);
#endif /* HAVE_MBRTOWC */
}
static int
decode_locale_impl(const char* arg, wchar_t **wstr, size_t *wlen,
int current_locale, _Py_error_handler errors)
{
if (current_locale) {
#ifdef _Py_FORCE_UTF8_LOCALE
return _Py_DecodeUTF8(arg, strlen(arg), wstr, wlen, errors);
#else
return decode_current_locale(arg, wstr, wlen, errors);
#endif
}
#ifdef _Py_FORCE_UTF8_FS_ENCODING
return _Py_DecodeUTF8(arg, strlen(arg), wstr, wlen, errors);
#else
int use_utf8 = (_PyRuntime.preconfig.utf8_mode >= 1);
#ifdef MS_WINDOWS
use_utf8 |= (_PyRuntime.preconfig.legacy_windows_fs_encoding == 0);
#endif
if (use_utf8) {
return _Py_DecodeUTF8(arg, strlen(arg), wstr, wlen, errors);
}
#ifdef USE_FORCE_ASCII
if (force_ascii == -1) {
force_ascii = check_force_ascii();
}
if (force_ascii) {
/* force ASCII encoding to workaround mbstowcs() issue */
return decode_ascii(arg, wstr, wlen, errors);
}
#endif
return decode_current_locale(arg, wstr, wlen, errors);
#endif /* !_Py_FORCE_UTF8_FS_ENCODING */
}
// Decode a byte string from the locale encoding.
//
// Supported error handlers are _Py_ERROR_STRICT and _Py_ERROR_SURROGATEESCAPE.
// The UTF-8 decoder also supports _Py_ERROR_SURROGATEPASS.
//
// If errors is _Py_ERROR_SURROGATEESCAPE, undecodable bytes are decoded as
// characters in range U+DC80..U+DCFF. If a byte sequence can be decoded as a
// surrogate character, escape the bytes using the surrogateescape error
// handler instead of decoding them.
//
// On success, return 0 and write the newly allocated wide character string into
// *wstr (use PyMem_RawFree() to free the memory). If wlen is not NULL, write
// the number of wide characters excluding the null character into *wlen.
//
// On error, return a negative number.
//
// On memory allocation failure, return _Py_CODEC_MEMORY_ERROR.
//
// On decoding error, return _Py_CODEC_DECODE_ERROR. If wlen is not NULL,
// write the start of invalid byte sequence in the input string into *wlen. If
// reason is not NULL, write the decoding error message into *reason.
//
// Return _Py_CODEC_UNSUPPORTED_ERROR_HANDLER if the 'errors' error
// handler is not supported: other than "strict" and "surrogateescape".
//
// Use the _Py_EncodeLocale() function to encode the character string back to
// a byte string.
//
// arg and wstr must not be NULL.
int
_Py_DecodeLocale(const char* arg, wchar_t **wstr, size_t *wlen,
int current_locale, _Py_error_handler errors)
{
assert(arg != NULL);
assert(wstr != NULL);
#ifdef Py_DEBUG
size_t arglen = strlen(arg);
size_t wlen_canary = (size_t)-2;
if (wlen) {
*wlen = wlen_canary;
}
#endif
int res = decode_locale_impl(arg, wstr, wlen, current_locale, errors);
if (res < 0) {
// Error
*wstr = NULL;
if (res == _Py_CODEC_DECODE_ERROR) {
#ifdef Py_DEBUG
assert(wlen == NULL || *wlen != wlen_canary);
#endif
}
else {
if (wlen) {
*wlen = 0;
}
}
}
else {
// Success
assert(*wstr != NULL);
#ifdef Py_DEBUG
// gh-158893: Detect if the input string was mutated during the
// function call. For example, the assertion fails on decoding
// strerror() result if another thread mutated the string in-place by
// calling strerror() in parallel.
assert(strlen(arg) == arglen);
if (wlen != NULL) {
assert(*wlen == wcslen(*wstr));
}
#endif
}
return res;
}
// Decode a byte string from the locale encoding with the
// surrogateescape error handler. Undecodable bytes are decoded as characters
// in range U+DC80..U+DCFF. If a byte sequence can be decoded as a surrogate
// character, escape the bytes using the surrogateescape error handler instead
// of decoding them.
//
// Return a pointer to a newly allocated wide character string, use
// PyMem_RawFree() to free the memory. If size is not NULL, write the number of
// wide characters excluding the null character into *size.
//
// On memory allocation failure, set *size to (size_t)-1 and return NULL.
//
// On decode error, set *size to (size_t)-2 and return NULL.
// Decoding errors should never happen, unless there is a bug in the C library.
//
// Use the Py_EncodeLocale() function to encode the character string back to a
// byte string.
wchar_t*
Py_DecodeLocale(const char* arg, size_t *size)
{
wchar_t *wstr;
int res = _Py_DecodeLocale(arg, &wstr, size, 0, _Py_ERROR_SURROGATEESCAPE);
if (res != 0) {
assert(res == _Py_CODEC_MEMORY_ERROR || res == _Py_CODEC_DECODE_ERROR);
if (size != NULL) {
*size = (size_t)res;
}
return NULL;
}
return wstr;
}
// If bytes is NULL, compute the length in 'bytes' of the encoded string.
// Otherwise, encode the wide string into 'bytes', decrements 'size', and
// return 0 on success.
// On encoding error, set 'error_pos' (if set) and return ENCODE_ERROR.
static size_t
encode_current_locale_impl(const wchar_t *text, const size_t len,
int surrogateescape,
char *bytes, size_t size,
size_t *error_pos)
{
wchar_t buf[2];
// The second character is always the NUL character
buf[1] = 0;
for (size_t i=0; i < len; i++) {
wchar_t c = text[i];
if (c >= 0xdc80 && c <= 0xdcff) {
if (!surrogateescape) {
if (error_pos != NULL) {
*error_pos = i;
}
return ENCODE_ERROR;
}
/* UTF-8b surrogate */
if (bytes != NULL) {
*bytes++ = c - 0xdc00;
size--;
}
else {
size++;
}
}
else {
// Encode a single character using wcstombs()
buf[0] = c;
size_t converted;
if (bytes != NULL) {
converted = wcstombs(bytes, buf, size);
}
else {
converted = wcstombs(NULL, buf, 0);
}
if (converted == ENCODE_ERROR) {
if (error_pos != NULL) {
*error_pos = i;
}
return ENCODE_ERROR;
}
if (bytes != NULL) {
bytes += converted;
size -= converted;
}
else {
size += converted;
}
}
}
if (bytes) {
*bytes = '\0';
}
// Sanity check, it cannot happen in practice
assert(size != ENCODE_ERROR);
return size;
}
// Encode a wide string to the current locale encoding.
// Set *str to a newly allocated string on success.
// Return a negative number on error: _Py_CODEC_MEMORY_ERROR,
// _Py_CODEC_ENCODE_ERROR or _Py_CODEC_UNSUPPORTED_ERROR_HANDLER.
//
// str and output_length must not be NULL
static int
encode_current_locale(const wchar_t *text, char **str, size_t *output_length,
size_t *error_pos, int raw_malloc,
_Py_error_handler errors)
{
assert(str != NULL);
assert(output_length != NULL);
int surrogateescape;
if (get_surrogateescape(errors, &surrogateescape) < 0) {
// Only support "strict" and "surrogateescape"
return _Py_CODEC_UNSUPPORTED_ERROR_HANDLER;
}
// First, compute the output length
const size_t len = wcslen(text);
// Sanity check, it cannot happen in practice
assert(len != ENCODE_ERROR);
size_t size = encode_current_locale_impl(text, len, surrogateescape,
NULL, 0, error_pos);
if (size == ENCODE_ERROR) {
return _Py_CODEC_ENCODE_ERROR;
}
*output_length = size;
char *result;
result = raw_malloc ? PyMem_RawMalloc(size + 1) : PyMem_Malloc(size + 1);
if (result == NULL) {
return _Py_CODEC_MEMORY_ERROR;
}
// Second, encode characters
size = encode_current_locale_impl(text, len, surrogateescape,
result, size, error_pos);
if (size == ENCODE_ERROR) {
if (raw_malloc) {
PyMem_RawFree(result);
}
else {
PyMem_Free(result);
}
return _Py_CODEC_ENCODE_ERROR;
}
assert(size == 0);
*str = result;
return 0;
}
static int
encode_locale_inner(const wchar_t *text, char **str, size_t *output_length,
size_t *error_pos, int raw_malloc,
int current_locale, _Py_error_handler errors)
{
if (current_locale) {
#ifdef _Py_FORCE_UTF8_LOCALE
return _Py_EncodeUTF8(text, str, output_length,
error_pos, raw_malloc, errors);
#else
return encode_current_locale(text, str, output_length,
error_pos, raw_malloc, errors);
#endif
}
#ifdef _Py_FORCE_UTF8_FS_ENCODING
return _Py_EncodeUTF8(text, str, output_length,
error_pos, raw_malloc, errors);
#else
int use_utf8 = (_PyRuntime.preconfig.utf8_mode >= 1);
#ifdef MS_WINDOWS
use_utf8 |= (_PyRuntime.preconfig.legacy_windows_fs_encoding == 0);
#endif
if (use_utf8) {
return _Py_EncodeUTF8(text, str, output_length,
error_pos, raw_malloc, errors);
}
#ifdef USE_FORCE_ASCII
if (force_ascii == -1) {
force_ascii = check_force_ascii();
}
if (force_ascii) {
return encode_ascii(text, str, output_length,
error_pos, raw_malloc, errors);
}
#endif
return encode_current_locale(text, str, output_length,
error_pos, raw_malloc, errors);
#endif /* _Py_FORCE_UTF8_FS_ENCODING */
}
// Encode a wide string to the locale encoding.
//
// Parameters:
//
// * raw_malloc: if non-zero, allocate memory using PyMem_RawMalloc() instead
// of PyMem_Malloc().
// * current_locale: if non-zero, use the current LC_CTYPE, otherwise use
// Python filesystem encoding.
// * errors: supported error handlers are _Py_ERROR_STRICT and
// _Py_ERROR_SURROGATEESCAPE. The UTF-8 encoder also supports
// _Py_ERROR_SURROGATEPASS.
//
// Set *str to a newly allocated decoded string and return 0 on success.
// Return a negative result on error:
//
// * _Py_CODEC_MEMORY_ERROR: memory allocation failure
// * _Py_CODEC_ENCODE_ERROR: encoding error, set *error_pos.
// * _Py_CODEC_UNSUPPORTED_ERROR_HANDLER: the 'errors' error handler
// is not supported.
//
// text, str and output_length must not be NULL.
static int
encode_locale_impl(const wchar_t *text, char **str, size_t *output_length,
size_t *error_pos, int raw_malloc,
int current_locale, _Py_error_handler errors)
{
assert(text != NULL);
assert(str != NULL);
assert(output_length != NULL);
int res = encode_locale_inner(text, str, output_length,
error_pos, raw_malloc,
current_locale, errors);
if (res < 0) {
// Error
*str = NULL;
*output_length = 0;
if (res != _Py_CODEC_ENCODE_ERROR) {
if (error_pos) {
*error_pos = 0;
}
}
}
else {
assert(*str != NULL);
assert(*output_length == strlen(*str));
// *error_pos is left unchanged
}
return res;
}
static char*
encode_locale(const wchar_t *text, size_t *error_pos,
int raw_malloc, int current_locale)
{
char *str;
size_t unused_output_length;
int res = encode_locale_impl(text, &str, &unused_output_length,