bpo-32030: Add _Py_FindEnvConfigValue() (#4963)

Add a new _Py_FindEnvConfigValue() function: code shared between
Windows and Unix implementations of _PyPathConfig_Calculate() to read
the pyenv.cfg file.

_Py_FindEnvConfigValue() now uses _Py_DecodeUTF8_surrogateescape()
instead of using a Python Unicode string, the Python API must not be
used early during Python initialization. Same change in Unix
search_for_exec_prefix(): use _Py_DecodeUTF8_surrogateescape().

Cleanup also encode_current_locale(): PyMem_RawFree/PyMem_Free can be
called with NULL.

Fix also "NUL byte" => "NULL byte" typo.
This commit is contained in:
Victor Stinner 2017-12-21 16:49:13 +01:00 committed by GitHub
parent 9dd762013f
commit 9bee329130
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
6 changed files with 80 additions and 135 deletions

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@ -19,6 +19,13 @@ PyAPI_FUNC(char*) _Py_EncodeLocaleRaw(
size_t *error_pos);
#endif
#ifdef Py_BUILD_CORE
PyAPI_FUNC(wchar_t*) _Py_DecodeUTF8_surrogateescape(
const char *s,
Py_ssize_t size,
size_t *p_wlen);
#endif
#ifndef Py_LIMITED_API
PyAPI_FUNC(PyObject *) _Py_device_encoding(int);

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@ -118,6 +118,11 @@ PyAPI_FUNC(wchar_t *) Py_GetPath(void);
#ifdef Py_BUILD_CORE
PyAPI_FUNC(_PyInitError) _PyPathConfig_Init(const _PyCoreConfig *core_config);
PyAPI_FUNC(PyObject*) _PyPathConfig_ComputeArgv0(int argc, wchar_t **argv);
PyAPI_FUNC(int) _Py_FindEnvConfigValue(
FILE *env_file,
const wchar_t *key,
wchar_t *value,
size_t value_size);
#endif
PyAPI_FUNC(void) Py_SetPath(const wchar_t *);
#ifdef MS_WINDOWS

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@ -296,62 +296,6 @@ absolutize(wchar_t *path)
}
/* search for a prefix value in an environment file. If found, copy it
to the provided buffer, which is expected to be no more than MAXPATHLEN
bytes long.
*/
static int
find_env_config_value(FILE * env_file, const wchar_t * key, wchar_t * value)
{
int result = 0; /* meaning not found */
char buffer[MAXPATHLEN*2+1]; /* allow extra for key, '=', etc. */
fseek(env_file, 0, SEEK_SET);
while (!feof(env_file)) {
char * p = fgets(buffer, MAXPATHLEN*2, env_file);
wchar_t tmpbuffer[MAXPATHLEN*2+1];
PyObject * decoded;
int n;
if (p == NULL) {
break;
}
n = strlen(p);
if (p[n - 1] != '\n') {
/* line has overflowed - bail */
break;
}
if (p[0] == '#') {
/* Comment - skip */
continue;
}
decoded = PyUnicode_DecodeUTF8(buffer, n, "surrogateescape");
if (decoded != NULL) {
Py_ssize_t k;
wchar_t * state;
k = PyUnicode_AsWideChar(decoded,
tmpbuffer, MAXPATHLEN * 2);
Py_DECREF(decoded);
if (k >= 0) {
wchar_t * tok = wcstok(tmpbuffer, L" \t\r\n", &state);
if ((tok != NULL) && !wcscmp(tok, key)) {
tok = wcstok(NULL, L" \t", &state);
if ((tok != NULL) && !wcscmp(tok, L"=")) {
tok = wcstok(NULL, L"\r\n", &state);
if (tok != NULL) {
wcsncpy(value, tok, MAXPATHLEN);
result = 1;
break;
}
}
}
}
}
}
return result;
}
/* search_for_prefix requires that argv0_path be no more than MAXPATHLEN
bytes long.
*/
@ -501,24 +445,17 @@ search_for_exec_prefix(const _PyCoreConfig *core_config,
}
else {
char buf[MAXPATHLEN+1];
PyObject *decoded;
wchar_t rel_builddir_path[MAXPATHLEN+1];
wchar_t *rel_builddir_path;
n = fread(buf, 1, MAXPATHLEN, f);
buf[n] = '\0';
fclose(f);
decoded = PyUnicode_DecodeUTF8(buf, n, "surrogateescape");
if (decoded != NULL) {
Py_ssize_t k;
k = PyUnicode_AsWideChar(decoded,
rel_builddir_path, MAXPATHLEN);
Py_DECREF(decoded);
if (k >= 0) {
rel_builddir_path[k] = L'\0';
wcsncpy(exec_prefix, calculate->argv0_path, MAXPATHLEN);
exec_prefix[MAXPATHLEN] = L'\0';
joinpath(exec_prefix, rel_builddir_path);
return -1;
}
rel_builddir_path = _Py_DecodeUTF8_surrogateescape(buf, n, NULL);
if (rel_builddir_path != NULL) {
wcsncpy(exec_prefix, calculate->argv0_path, MAXPATHLEN);
exec_prefix[MAXPATHLEN] = L'\0';
joinpath(exec_prefix, rel_builddir_path);
PyMem_RawFree(rel_builddir_path );
return -1;
}
}
}
@ -784,7 +721,7 @@ calculate_read_pyenv(PyCalculatePath *calculate)
}
/* Look for a 'home' variable and set argv0_path to it, if found */
if (find_env_config_value(env_file, L"home", tmpbuffer)) {
if (_Py_FindEnvConfigValue(env_file, L"home", tmpbuffer, MAXPATHLEN)) {
wcscpy(calculate->argv0_path, tmpbuffer);
}
fclose(env_file);

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@ -564,58 +564,6 @@ done:
}
static int
find_env_config_value(FILE * env_file, const wchar_t * key, wchar_t * value)
{
int result = 0; /* meaning not found */
char buffer[MAXPATHLEN*2+1]; /* allow extra for key, '=', etc. */
fseek(env_file, 0, SEEK_SET);
while (!feof(env_file)) {
char * p = fgets(buffer, MAXPATHLEN*2, env_file);
wchar_t tmpbuffer[MAXPATHLEN*2+1];
PyObject * decoded;
size_t n;
if (p == NULL) {
break;
}
n = strlen(p);
if (p[n - 1] != '\n') {
/* line has overflowed - bail */
break;
}
if (p[0] == '#') {
/* Comment - skip */
continue;
}
decoded = PyUnicode_DecodeUTF8(buffer, n, "surrogateescape");
if (decoded != NULL) {
Py_ssize_t k;
k = PyUnicode_AsWideChar(decoded,
tmpbuffer, MAXPATHLEN * 2);
Py_DECREF(decoded);
if (k >= 0) {
wchar_t * context = NULL;
wchar_t * tok = wcstok_s(tmpbuffer, L" \t\r\n", &context);
if ((tok != NULL) && !wcscmp(tok, key)) {
tok = wcstok_s(NULL, L" \t", &context);
if ((tok != NULL) && !wcscmp(tok, L"=")) {
tok = wcstok_s(NULL, L"\r\n", &context);
if (tok != NULL) {
wcsncpy(value, tok, MAXPATHLEN);
result = 1;
break;
}
}
}
}
}
}
return result;
}
static int
read_pth_file(_PyPathConfig *config, wchar_t *prefix, const wchar_t *path,
int *isolated, int *nosite)
@ -765,9 +713,11 @@ calculate_pyvenv_file(PyCalculatePath *calculate)
FILE *env_file = _Py_wfopen(envbuffer, L"r");
if (env_file == NULL) {
errno = 0;
reduce(envbuffer);
reduce(envbuffer);
join(envbuffer, env_cfg);
env_file = _Py_wfopen(envbuffer, L"r");
if (env_file == NULL) {
errno = 0;
@ -780,7 +730,7 @@ calculate_pyvenv_file(PyCalculatePath *calculate)
/* Look for a 'home' variable and set argv0_path to it, if found */
wchar_t tmpbuffer[MAXPATHLEN+1];
if (find_env_config_value(env_file, L"home", tmpbuffer)) {
if (_Py_FindEnvConfigValue(env_file, L"home", tmpbuffer, MAXPATHLEN)) {
wcscpy_s(calculate->argv0_path, MAXPATHLEN+1, tmpbuffer);
}
fclose(env_file);

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@ -20,8 +20,6 @@ extern int winerror_to_errno(int);
#include <fcntl.h>
#endif /* HAVE_FCNTL_H */
extern wchar_t* _Py_DecodeUTF8_surrogateescape(const char *s, Py_ssize_t size,
size_t *p_wlen);
extern char* _Py_EncodeUTF8_surrogateescape(const wchar_t *text,
size_t *error_pos, int raw_malloc);
@ -194,7 +192,7 @@ encode_ascii_surrogateescape(const wchar_t *text, size_t *error_pos, int raw_mal
len = wcslen(text);
/* +1 for NUL byte */
/* +1 for NULL byte */
if (raw_malloc) {
result = PyMem_RawMalloc(len + 1);
}
@ -467,13 +465,11 @@ encode_current_locale(const wchar_t *text, size_t *error_pos, int raw_malloc)
else
converted = wcstombs(NULL, buf, 0);
if (converted == (size_t)-1) {
if (result != NULL) {
if (raw_malloc) {
PyMem_RawFree(result);
}
else {
PyMem_Free(result);
}
if (raw_malloc) {
PyMem_RawFree(result);
}
else {
PyMem_Free(result);
}
if (error_pos != NULL)
*error_pos = i;

View File

@ -354,6 +354,56 @@ _PyPathConfig_ComputeArgv0(int argc, wchar_t **argv)
return PyUnicode_FromWideChar(argv0, n);
}
/* Search for a prefix value in an environment file (pyvenv.cfg).
If found, copy it into the provided buffer. */
int
_Py_FindEnvConfigValue(FILE *env_file, const wchar_t *key,
wchar_t *value, size_t value_size)
{
int result = 0; /* meaning not found */
char buffer[MAXPATHLEN*2+1]; /* allow extra for key, '=', etc. */
fseek(env_file, 0, SEEK_SET);
while (!feof(env_file)) {
char * p = fgets(buffer, MAXPATHLEN*2, env_file);
wchar_t *tmpbuffer;
int n;
if (p == NULL) {
break;
}
n = strlen(p);
if (p[n - 1] != '\n') {
/* line has overflowed - bail */
break;
}
if (p[0] == '#') {
/* Comment - skip */
continue;
}
tmpbuffer = _Py_DecodeUTF8_surrogateescape(buffer, n, NULL);
if (tmpbuffer != NULL) {
wchar_t * state;
wchar_t * tok = wcstok(tmpbuffer, L" \t\r\n", &state);
if ((tok != NULL) && !wcscmp(tok, key)) {
tok = wcstok(NULL, L" \t", &state);
if ((tok != NULL) && !wcscmp(tok, L"=")) {
tok = wcstok(NULL, L"\r\n", &state);
if (tok != NULL) {
wcsncpy(value, tok, MAXPATHLEN);
result = 1;
PyMem_RawFree(tmpbuffer);
break;
}
}
}
PyMem_RawFree(tmpbuffer);
}
}
return result;
}
#ifdef __cplusplus
}
#endif