Fixed several corner case issues on os.stat/os.lstat related to reparse

points. (Windows)

- Set S_IEXEC via final path name not link name.
- Set S_IFLNK also via FindFirstFile (when CreateFile fails)
This commit is contained in:
Hirokazu Yamamoto 2010-12-04 10:16:05 +00:00
parent b4162305bb
commit 427d3149eb
2 changed files with 116 additions and 96 deletions

View File

@ -10,6 +10,9 @@ What's New in Python 3.2 Beta 1?
Core and Builtins
-----------------
- Fixed several corner case issues on os.stat/os.lstat related to reparse
points. (Windows)
- PEP 384 (Defining a Stable ABI) is implemented.
- Issue #2690: Range objects support negative indices and slicing

View File

@ -477,7 +477,7 @@ typedef struct _REPARSE_DATA_BUFFER {
#define MAXIMUM_REPARSE_DATA_BUFFER_SIZE ( 16 * 1024 )
static int
_Py_ReadLink(HANDLE reparse_point_handle, ULONG *reparse_tag, wchar_t **target_path)
win32_read_link(HANDLE reparse_point_handle, ULONG *reparse_tag, wchar_t **target_path)
{
char target_buffer[MAXIMUM_REPARSE_DATA_BUFFER_SIZE];
REPARSE_DATA_BUFFER *rdb = (REPARSE_DATA_BUFFER *)target_buffer;
@ -493,7 +493,7 @@ _Py_ReadLink(HANDLE reparse_point_handle, ULONG *reparse_tag, wchar_t **target_p
target_buffer, sizeof(target_buffer),
&n_bytes_returned,
NULL)) /* we're not using OVERLAPPED_IO */
return 0;
return -1;
if (reparse_tag)
*reparse_tag = rdb->ReparseTag;
@ -513,12 +513,12 @@ _Py_ReadLink(HANDLE reparse_point_handle, ULONG *reparse_tag, wchar_t **target_p
break;
default:
SetLastError(ERROR_REPARSE_TAG_MISMATCH); /* XXX: Proper error code? */
return 0;
return -1;
}
buf = (wchar_t *)malloc(sizeof(wchar_t)*(len+1));
if (!buf) {
SetLastError(ERROR_OUTOFMEMORY);
return 0;
return -1;
}
wcsncpy(buf, ptr, len);
buf[len] = L'\0';
@ -527,7 +527,7 @@ _Py_ReadLink(HANDLE reparse_point_handle, ULONG *reparse_tag, wchar_t **target_p
*target_path = buf;
}
return 1;
return 0;
}
#endif /* MS_WINDOWS */
@ -1028,7 +1028,7 @@ attributes_to_mode(DWORD attr)
}
static int
attribute_data_to_stat(BY_HANDLE_FILE_INFORMATION *info, struct win32_stat *result)
attribute_data_to_stat(BY_HANDLE_FILE_INFORMATION *info, ULONG reparse_tag, struct win32_stat *result)
{
memset(result, 0, sizeof(*result));
result->st_mode = attributes_to_mode(info->dwFileAttributes);
@ -1038,12 +1038,18 @@ attribute_data_to_stat(BY_HANDLE_FILE_INFORMATION *info, struct win32_stat *resu
FILE_TIME_to_time_t_nsec(&info->ftLastAccessTime, &result->st_atime, &result->st_atime_nsec);
result->st_nlink = info->nNumberOfLinks;
result->st_ino = (((__int64)info->nFileIndexHigh)<<32) + info->nFileIndexLow;
if (reparse_tag == IO_REPARSE_TAG_SYMLINK) {
/* first clear the S_IFMT bits */
result->st_mode ^= (result->st_mode & 0170000);
/* now set the bits that make this a symlink */
result->st_mode |= 0120000;
}
return 0;
}
static BOOL
attributes_from_dir(LPCSTR pszFile, BY_HANDLE_FILE_INFORMATION *info)
attributes_from_dir(LPCSTR pszFile, BY_HANDLE_FILE_INFORMATION *info, ULONG *reparse_tag)
{
HANDLE hFindFile;
WIN32_FIND_DATAA FileData;
@ -1052,6 +1058,7 @@ attributes_from_dir(LPCSTR pszFile, BY_HANDLE_FILE_INFORMATION *info)
return FALSE;
FindClose(hFindFile);
memset(info, 0, sizeof(*info));
*reparse_tag = 0;
info->dwFileAttributes = FileData.dwFileAttributes;
info->ftCreationTime = FileData.ftCreationTime;
info->ftLastAccessTime = FileData.ftLastAccessTime;
@ -1059,11 +1066,13 @@ attributes_from_dir(LPCSTR pszFile, BY_HANDLE_FILE_INFORMATION *info)
info->nFileSizeHigh = FileData.nFileSizeHigh;
info->nFileSizeLow = FileData.nFileSizeLow;
/* info->nNumberOfLinks = 1; */
if (FileData.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT)
*reparse_tag = FileData.dwReserved0;
return TRUE;
}
static BOOL
attributes_from_dir_w(LPCWSTR pszFile, BY_HANDLE_FILE_INFORMATION *info)
attributes_from_dir_w(LPCWSTR pszFile, BY_HANDLE_FILE_INFORMATION *info, ULONG *reparse_tag)
{
HANDLE hFindFile;
WIN32_FIND_DATAW FileData;
@ -1072,6 +1081,7 @@ attributes_from_dir_w(LPCWSTR pszFile, BY_HANDLE_FILE_INFORMATION *info)
return FALSE;
FindClose(hFindFile);
memset(info, 0, sizeof(*info));
*reparse_tag = 0;
info->dwFileAttributes = FileData.dwFileAttributes;
info->ftCreationTime = FileData.ftCreationTime;
info->ftLastAccessTime = FileData.ftLastAccessTime;
@ -1079,6 +1089,8 @@ attributes_from_dir_w(LPCWSTR pszFile, BY_HANDLE_FILE_INFORMATION *info)
info->nFileSizeHigh = FileData.nFileSizeHigh;
info->nFileSizeLow = FileData.nFileSizeLow;
/* info->nNumberOfLinks = 1; */
if (FileData.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT)
*reparse_tag = FileData.dwReserved0;
return TRUE;
}
@ -1087,16 +1099,23 @@ attributes_from_dir_w(LPCWSTR pszFile, BY_HANDLE_FILE_INFORMATION *info)
#endif
static int
win32_xstat_for_handle(HANDLE hFile, struct win32_stat *result, BOOL traverse, int depth);
win32_xstat_impl_w(const wchar_t *path, struct win32_stat *result, BOOL traverse, int depth);
static int
win32_xstat(const char *path, struct win32_stat *result, BOOL traverse, int depth)
win32_xstat_impl(const char *path, struct win32_stat *result, BOOL traverse, int depth)
{
int code;
HANDLE hFile;
BY_HANDLE_FILE_INFORMATION info;
ULONG reparse_tag = 0;
wchar_t *target_path;
const char *dot;
if (depth > SYMLOOP_MAX) {
SetLastError(ERROR_CANT_RESOLVE_FILENAME); /* XXX: ELOOP? */
return -1;
}
hFile = CreateFileA(
path,
0, /* desired access */
@ -1107,32 +1126,43 @@ win32_xstat(const char *path, struct win32_stat *result, BOOL traverse, int dept
FILE_ATTRIBUTE_NORMAL|FILE_FLAG_BACKUP_SEMANTICS|FILE_FLAG_OPEN_REPARSE_POINT,
NULL);
if(hFile == INVALID_HANDLE_VALUE) {
if (hFile == INVALID_HANDLE_VALUE) {
/* Either the target doesn't exist, or we don't have access to
get a handle to it. If the former, we need to return an error.
If the latter, we can use attributes_from_dir. */
if (GetLastError() != ERROR_SHARING_VIOLATION)
goto err;
else {
/* Could not get attributes on open file. Fall back to
reading the directory. */
if (!attributes_from_dir(path, &info))
/* Very strange. This should not fail now */
goto err;
if (traverse && (info.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
/* Should traverse, but cannot open reparse point handle */
return -1;
/* Could not get attributes on open file. Fall back to
reading the directory. */
if (!attributes_from_dir(path, &info, &reparse_tag))
/* Very strange. This should not fail now */
return -1;
if (info.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
if (traverse) {
/* Should traverse, but could not open reparse point handle */
SetLastError(ERROR_SHARING_VIOLATION);
goto err;
return -1;
}
}
} else {
if (!GetFileInformationByHandle(hFile, &info)) {
CloseHandle(hFile);
return -1;;
}
if (info.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
code = win32_read_link(hFile, &reparse_tag, traverse ? &target_path : NULL);
CloseHandle(hFile);
if (code < 0)
return code;
if (traverse) {
code = win32_xstat_impl_w(target_path, result, traverse, depth + 1);
free(target_path);
return code;
}
attribute_data_to_stat(&info, result);
}
}
else {
code = win32_xstat_for_handle(hFile, result, traverse, depth);
CloseHandle(hFile);
if (code != 0)
return code;
}
attribute_data_to_stat(&info, reparse_tag, result);
/* Set S_IEXEC if it is an .exe, .bat, ... */
dot = strrchr(path, '.');
@ -1142,22 +1172,23 @@ win32_xstat(const char *path, struct win32_stat *result, BOOL traverse, int dept
result->st_mode |= 0111;
}
return 0;
err:
/* Protocol violation: we explicitly clear errno, instead of
setting it to a POSIX error. Callers should use GetLastError. */
errno = 0;
return -1;
}
static int
win32_xstat_w(const wchar_t *path, struct win32_stat *result, BOOL traverse, int depth)
win32_xstat_impl_w(const wchar_t *path, struct win32_stat *result, BOOL traverse, int depth)
{
int code;
HANDLE hFile;
BY_HANDLE_FILE_INFORMATION info;
ULONG reparse_tag = 0;
wchar_t *target_path;
const wchar_t *dot;
if (depth > SYMLOOP_MAX) {
SetLastError(ERROR_CANT_RESOLVE_FILENAME); /* XXX: ELOOP? */
return -1;
}
hFile = CreateFileW(
path,
0, /* desired access */
@ -1168,32 +1199,43 @@ win32_xstat_w(const wchar_t *path, struct win32_stat *result, BOOL traverse, int
FILE_ATTRIBUTE_NORMAL|FILE_FLAG_BACKUP_SEMANTICS|FILE_FLAG_OPEN_REPARSE_POINT,
NULL);
if(hFile == INVALID_HANDLE_VALUE) {
if (hFile == INVALID_HANDLE_VALUE) {
/* Either the target doesn't exist, or we don't have access to
get a handle to it. If the former, we need to return an error.
If the latter, we can use attributes_from_dir. */
if (GetLastError() != ERROR_SHARING_VIOLATION)
goto err;
else {
/* Could not get attributes on open file. Fall back to
reading the directory. */
if (!attributes_from_dir_w(path, &info))
/* Very strange. This should not fail now */
goto err;
if (traverse && (info.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
/* Should traverse, but cannot open reparse point handle */
return -1;
/* Could not get attributes on open file. Fall back to
reading the directory. */
if (!attributes_from_dir_w(path, &info, &reparse_tag))
/* Very strange. This should not fail now */
return -1;
if (info.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
if (traverse) {
/* Should traverse, but could not open reparse point handle */
SetLastError(ERROR_SHARING_VIOLATION);
goto err;
return -1;
}
}
} else {
if (!GetFileInformationByHandle(hFile, &info)) {
CloseHandle(hFile);
return -1;;
}
if (info.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
code = win32_read_link(hFile, &reparse_tag, traverse ? &target_path : NULL);
CloseHandle(hFile);
if (code < 0)
return code;
if (traverse) {
code = win32_xstat_impl_w(target_path, result, traverse, depth + 1);
free(target_path);
return code;
}
attribute_data_to_stat(&info, result);
}
}
else {
code = win32_xstat_for_handle(hFile, result, traverse, depth);
CloseHandle(hFile);
if (code != 0)
return code;
}
attribute_data_to_stat(&info, reparse_tag, result);
/* Set S_IEXEC if it is an .exe, .bat, ... */
dot = wcsrchr(path, '.');
@ -1203,51 +1245,26 @@ win32_xstat_w(const wchar_t *path, struct win32_stat *result, BOOL traverse, int
result->st_mode |= 0111;
}
return 0;
err:
/* Protocol violation: we explicitly clear errno, instead of
setting it to a POSIX error. Callers should use GetLastError. */
errno = 0;
return -1;
}
static int
win32_xstat_for_handle(HANDLE hFile, struct win32_stat *result, BOOL traverse, int depth)
win32_xstat(const char *path, struct win32_stat *result, BOOL traverse)
{
int code;
BOOL reparse_tag;
wchar_t *target_path;
BY_HANDLE_FILE_INFORMATION info;
/* Protocol violation: we explicitly clear errno, instead of
setting it to a POSIX error. Callers should use GetLastError. */
int code = win32_xstat_impl(path, result, traverse, 0);
errno = 0;
return code;
}
if (!GetFileInformationByHandle(hFile, &info))
return -1;
if (info.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
if (traverse) {
if (depth + 1 > SYMLOOP_MAX) {
SetLastError(ERROR_CANT_RESOLVE_FILENAME); /* XXX: ELOOP? */
return -1;
}
if (!_Py_ReadLink(hFile, NULL, &target_path))
return -1;
code = win32_xstat_w(target_path, result, traverse, depth + 1);
free(target_path);
return code;
} else {
if (!_Py_ReadLink(hFile, &reparse_tag, NULL))
return -1;
attribute_data_to_stat(&info, result);
if (reparse_tag == IO_REPARSE_TAG_SYMLINK) {
/* first clear the S_IFMT bits */
result->st_mode ^= (result->st_mode & 0170000);
/* now set the bits that make this a symlink */
result->st_mode |= 0120000;
}
}
} else {
attribute_data_to_stat(&info, result);
}
return 0;
static int
win32_xstat_w(const wchar_t *path, struct win32_stat *result, BOOL traverse)
{
/* Protocol violation: we explicitly clear errno, instead of
setting it to a POSIX error. Callers should use GetLastError. */
int code = win32_xstat_impl_w(path, result, traverse, 0);
errno = 0;
return code;
}
/* About the following functions: win32_lstat, win32_lstat_w, win32_stat,
@ -1267,25 +1284,25 @@ win32_xstat_for_handle(HANDLE hFile, struct win32_stat *result, BOOL traverse, i
static int
win32_lstat(const char* path, struct win32_stat *result)
{
return win32_xstat(path, result, FALSE, 0);
return win32_xstat(path, result, FALSE);
}
static int
win32_lstat_w(const wchar_t* path, struct win32_stat *result)
{
return win32_xstat_w(path, result, FALSE, 0);
return win32_xstat_w(path, result, FALSE);
}
static int
win32_stat(const char* path, struct win32_stat *result)
{
return win32_xstat(path, result, TRUE, 0);
return win32_xstat(path, result, TRUE);
}
static int
win32_stat_w(const wchar_t* path, struct win32_stat *result)
{
return win32_xstat_w(path, result, TRUE, 0);
return win32_xstat_w(path, result, TRUE);
}
static int
@ -1330,7 +1347,7 @@ win32_fstat(int file_number, struct win32_stat *result)
return -1;
}
attribute_data_to_stat(&info, result);
attribute_data_to_stat(&info, 0, result);
/* specific to fstat() */
result->st_ino = (((__int64)info.nFileIndexHigh)<<32) + info.nFileIndexLow;
return 0;