diff options
| -rw-r--r-- | indra/llcommon/llfile.cpp | 154 | ||||
| -rw-r--r-- | indra/llcommon/llfile.h | 46 |
2 files changed, 123 insertions, 77 deletions
diff --git a/indra/llcommon/llfile.cpp b/indra/llcommon/llfile.cpp index a24524d699..492c7c690b 100644 --- a/indra/llcommon/llfile.cpp +++ b/indra/llcommon/llfile.cpp @@ -48,15 +48,18 @@ static std::string empty; // variants of strerror() to report errors. #if LL_WINDOWS +// For the situations where we directly call into Windows API functions we need to translate +// the Windows error codes into errno values namespace { struct errentry { - unsigned long oserr; // OS return value + unsigned long oserr; // Windows OS error value int errcode; // System V error code }; } +// translation table between Windows OS error value and System V errno code static errentry const errtable[] { { ERROR_INVALID_FUNCTION, EINVAL }, // 1 @@ -106,20 +109,17 @@ static errentry const errtable[] { ERROR_NOT_ENOUGH_QUOTA, ENOMEM } // 1816 }; -// Number of elements in the error translation table -#define ERRTABLECOUNT (sizeof(errtable) / sizeof(errtable[0])) - static int set_errno_from_oserror(unsigned long oserr) { if (!oserr) return 0; - // Check the table for the OS error code - for (unsigned i{0}; i < ERRTABLECOUNT; ++i) + // Check the table for the Windows OS error code + for (const struct errentry &entry : errtable) { - if (oserr == errtable[i].oserr) + if (oserr == entry.oserr) { - _set_errno(errtable[i].errcode); + _set_errno(entry.errcode); return -1; } } @@ -156,40 +156,46 @@ static std::wstring utf8path_to_wstring(const std::string& utf8path) return ll_convert<std::wstring>(utf8path); } -static unsigned short get_fileattr(const std::wstring& utf16path) +static unsigned short get_fileattr(const std::wstring& utf16path, bool dontFollowSymLink = false) { - unsigned short st_mode = 0; - HANDLE file_handle = CreateFileW(utf16path.c_str(), FILE_READ_ATTRIBUTES, - FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE, nullptr, - OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, nullptr); - if (file_handle == INVALID_HANDLE_VALUE) + unsigned long flags = FILE_FLAG_BACKUP_SEMANTICS; + if (dontFollowSymLink) { - set_errno_from_oserror(GetLastError()); - return 0; + flags |= FILE_FLAG_OPEN_REPARSE_POINT; } - - FILE_ATTRIBUTE_TAG_INFO attribute_info; - if (GetFileInformationByHandleEx(file_handle, FileAttributeTagInfo, &attribute_info, sizeof(attribute_info))) + HANDLE file_handle = CreateFileW(utf16path.c_str(), FILE_READ_ATTRIBUTES, + FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE, + nullptr, OPEN_EXISTING, flags, nullptr); + if (file_handle != INVALID_HANDLE_VALUE) { - // A volume path alone (only drive letter) is not recognized as directory while it technically is - bool is_directory = (attribute_info.FileAttributes & FILE_ATTRIBUTE_DIRECTORY) || - (iswalpha(utf16path[0]) && utf16path[1] == ':' && - (!utf16path[2] || (is_slash(utf16path[2]) && !utf16path[3]))); - st_mode |= is_directory ? S_IFDIR : S_IFREG; - st_mode |= (attribute_info.FileAttributes & FILE_ATTRIBUTE_READONLY) ? S_IREAD : S_IREAD | S_IWRITE; - // we do not try to guess executable flag - - // propagate user bits to group/other fields: - st_mode |= (st_mode & 0700) >> 3; - st_mode |= (st_mode & 0700) >> 6; + FILE_ATTRIBUTE_TAG_INFO attribute_info; + if (GetFileInformationByHandleEx(file_handle, FileAttributeTagInfo, &attribute_info, sizeof(attribute_info))) + { + // A volume path alone (only drive letter) is not recognized as directory while it technically is + bool is_directory = (attribute_info.FileAttributes & FILE_ATTRIBUTE_DIRECTORY) || + (iswalpha(utf16path[0]) && utf16path[1] == ':' && + (!utf16path[2] || (is_slash(utf16path[2]) && !utf16path[3]))); + unsigned short st_mode = is_directory ? S_IFDIR : + (attribute_info.FileAttributes & FILE_ATTRIBUTE_REPARSE_POINT ? S_IFLNK : S_IFREG); + st_mode |= (attribute_info.FileAttributes & FILE_ATTRIBUTE_READONLY) ? S_IREAD : S_IREAD | S_IWRITE; + // we do not try to guess executable flag + + // propagate user bits to group/other fields: + st_mode |= (st_mode & 0700) >> 3; + st_mode |= (st_mode & 0700) >> 6; + + CloseHandle(file_handle); + return st_mode; + } } - else + // Retrieve last error and set errno before calling CloseHandle() + set_errno_from_oserror(GetLastError()); + + if (file_handle != INVALID_HANDLE_VALUE) { - // Retrieve last error before calling CloseHandle() - set_errno_from_oserror(GetLastError()); + CloseHandle(file_handle); } - CloseHandle(file_handle); - return st_mode; + return 0; } #else @@ -241,7 +247,7 @@ std::string strerr(int errn) } #endif // ! LL_WINDOWS -int warnif(const std::string& desc, const std::string& filename, int rc, int accept = 0) +static int warnif(const std::string& desc, const std::string& filename, int rc, int accept = 0) { if (rc < 0) { @@ -333,7 +339,7 @@ int LLFile::mkdir(const std::string& dirname, int perms) } // static -int LLFile::rmdir(const std::string& dirname, int supress_error) +int LLFile::rmdir(const std::string& dirname, int suppress_error) { #if LL_WINDOWS std::wstring utf16dirname = utf8path_to_wstring(dirname); @@ -341,21 +347,22 @@ int LLFile::rmdir(const std::string& dirname, int supress_error) #else int rc = ::rmdir(dirname.c_str()); #endif - return warnif("rmdir", dirname, rc, supress_error); + return warnif("rmdir", dirname, rc, suppress_error); } // static -LLFILE* LLFile::fopen(const std::string& filename, const char* mode) /* Flawfinder: ignore */ +LLFILE* LLFile::fopen(const std::string& filename, const char* mode) { #if LL_WINDOWS std::wstring utf16filename = utf8path_to_wstring(filename); std::wstring utf16mode = ll_convert<std::wstring>(std::string(mode)); return _wfopen(utf16filename.c_str(), utf16mode.c_str()); #else - return ::fopen(filename.c_str(),mode); /* Flawfinder: ignore */ + return ::fopen(filename.c_str(),mode); #endif } +// static int LLFile::close(LLFILE * file) { int ret_value = 0; @@ -366,9 +373,10 @@ int LLFile::close(LLFILE * file) return ret_value; } +// static std::string LLFile::getContents(const std::string& filename) { - LLFILE* fp = fopen(filename, "rb"); /* Flawfinder: ignore */ + LLFILE* fp = LLFile::fopen(filename, "rb"); if (fp) { fseek(fp, 0, SEEK_END); @@ -385,7 +393,8 @@ std::string LLFile::getContents(const std::string& filename) return LLStringUtil::null; } -int LLFile::remove(const std::string& filename, int supress_error) +// static +int LLFile::remove(const std::string& filename, int suppress_error) { #if LL_WINDOWS // Posix remove() works on both files and directories although on Windows @@ -393,8 +402,7 @@ int LLFile::remove(const std::string& filename, int supress_error) // as its siblings unlink() and _wunlink(). // If we really only want to support files we should instead use // unlink() in the non-Windows part below too - int rc = 0; - ; + int rc = -1; std::wstring utf16filename = utf8path_to_wstring(filename); unsigned short st_mode = get_fileattr(utf16filename); if (S_ISDIR(st_mode)) @@ -405,17 +413,25 @@ int LLFile::remove(const std::string& filename, int supress_error) { rc = _wunlink(utf16filename.c_str()); } - else + else if (st_mode) { + // it is something else than a file or directory + // this should not really happen as long as we do not allow for symlink + // detection in the optional parameter to get_fileattr() rc = set_errno_from_oserror(ERROR_INVALID_PARAMETER); } + else + { + // get_filattr() failed and already set errno, preserve it for correct error reporting + } #else int rc = ::remove(filename.c_str()); #endif - return warnif("remove", filename, rc, supress_error); + return warnif("remove", filename, rc, suppress_error); } -int LLFile::rename(const std::string& filename, const std::string& newname, int supress_error) +// static +int LLFile::rename(const std::string& filename, const std::string& newname, int suppress_error) { #if LL_WINDOWS // Posix rename() will gladly overwrite a file at newname if it exists, the Windows @@ -431,25 +447,26 @@ int LLFile::rename(const std::string& filename, const std::string& newname, int #else int rc = ::rename(filename.c_str(),newname.c_str()); #endif - return warnif(STRINGIZE("rename to '" << newname << "' from"), filename, rc, supress_error); + return warnif(STRINGIZE("rename to '" << newname << "' from"), filename, rc, suppress_error); } // Make this a define rather than using magic numbers multiple times in the code #define LLFILE_COPY_BUFFER_SIZE 16384 +// static bool LLFile::copy(const std::string& from, const std::string& to) { bool copied = false; - LLFILE* in = fopen(from, "rb"); /* Flawfinder: ignore */ + LLFILE* in = LLFile::fopen(from, "rb"); if (in) { - LLFILE* out = fopen(to, "wb"); /* Flawfinder: ignore */ + LLFILE* out = LLFile::fopen(to, "wb"); if (out) { - char buf[LLFILE_COPY_BUFFER_SIZE]; /* Flawfinder: ignore */ + char buf[LLFILE_COPY_BUFFER_SIZE]; size_t readbytes; bool write_ok = true; - while (write_ok && (readbytes = fread(buf, 1, LLFILE_COPY_BUFFER_SIZE, in))) /* Flawfinder: ignore */ + while (write_ok && (readbytes = fread(buf, 1, LLFILE_COPY_BUFFER_SIZE, in))) { if (fwrite(buf, 1, readbytes, out) != readbytes) { @@ -468,7 +485,8 @@ bool LLFile::copy(const std::string& from, const std::string& to) return copied; } -int LLFile::stat(const std::string& filename, llstat* filestatus, int supress_error) +// static +int LLFile::stat(const std::string& filename, llstat* filestatus, int suppress_error) { #if LL_WINDOWS std::wstring utf16filename = utf8path_to_wstring(filename); @@ -476,24 +494,25 @@ int LLFile::stat(const std::string& filename, llstat* filestatus, int supress_er #else int rc = ::stat(filename.c_str(), filestatus); #endif - return warnif("stat", filename, rc, supress_error); + return warnif("stat", filename, rc, suppress_error); } -// _wstat() is a bit heavyweight on Windows, use a more lightweight API -// to just get the attributes -unsigned short LLFile::getattr(const std::string& filename, int suppress_error) +// static +unsigned short LLFile::getattr(const std::string& filename, bool dontFollowSymLink, int suppress_error) { #if LL_WINDOWS - int rc = -1; + // _wstat64() is a bit heavyweight on Windows, use a more lightweight API + // to just get the attributes + int rc = -1; std::wstring utf16filename = utf8path_to_wstring(filename); - unsigned short st_mode = get_fileattr(utf16filename); + unsigned short st_mode = get_fileattr(utf16filename, dontFollowSymLink); if (st_mode) { return st_mode; } #else llstat filestatus; - int rc = ::stat(filename.c_str(), &filestatus); + int rc = dontFollowSymLink ? ::lstat(filename.c_str(), &filestatus) : ::stat(filename.c_str(), &filestatus); if (rc == 0) { return filestatus.st_mode; @@ -503,18 +522,25 @@ unsigned short LLFile::getattr(const std::string& filename, int suppress_error) return 0; } +// static bool LLFile::isdir(const std::string& filename) { - // Don't spam the log if the subject pathname doesn't exist. - return S_ISDIR(getattr(filename, ENOENT)); + return S_ISDIR(getattr(filename)); } +// static bool LLFile::isfile(const std::string& filename) { - // Don't spam the log if the subject pathname doesn't exist. - return S_ISREG(getattr(filename, ENOENT)); + return S_ISREG(getattr(filename)); +} + +// static +bool LLFile::islink(const std::string& filename) +{ + return S_ISLNK(getattr(filename, true)); } +// static const char *LLFile::tmpdir() { static std::string utf8path; diff --git a/indra/llcommon/llfile.h b/indra/llcommon/llfile.h index 9747bb67d8..04a2946ac4 100644 --- a/indra/llcommon/llfile.h +++ b/indra/llcommon/llfile.h @@ -41,8 +41,9 @@ typedef FILE LLFILE; #include <sys/stat.h> #if LL_WINDOWS -// windows version of stat function and stat data structure are called _statxx -typedef struct _stat64 llstat; +// The Windows version of stat function and stat data structure are called _stat64 +// We use _stat64 here to support 64-bit st_size and time_t values +typedef struct _stat64 llstat; #else typedef struct stat llstat; #include <sys/types.h> @@ -56,6 +57,16 @@ typedef struct stat llstat; # define S_ISDIR(x) (((x) & S_IFMT) == S_IFDIR) #endif +// Windows C runtime library does not define this and does not support symlink detection in the +// stat functions but we do in our getattr() function +#ifndef S_IFLNK +#define S_IFLNK 0xA000 /* symlink */ +#endif + +#ifndef S_ISLNK +#define S_ISLNK(x) (((x) & S_IFMT) == S_IFLNK) +#endif + #include "llstring.h" // safe char* -> std::string conversion /// LLFile is a class of static functions operating on paths @@ -96,39 +107,44 @@ public: /// @returns 0 on success and -1 on failure. //// remove a directory - static int rmdir(const std::string& filename, int supress_error = 0); - ///< pass ENOENT in the optional 'supress_error' parameter + static int rmdir(const std::string& filename, int suppress_error = 0); + ///< pass ENOENT in the optional 'suppress_error' parameter /// if you don't want a warning in the log when the directory does not exist /// @returns 0 on success and -1 on failure. /// remove a file or directory - static int remove(const std::string& filename, int supress_error = 0); - ///< pass ENOENT in the optional 'supress_error' parameter + static int remove(const std::string& filename, int suppress_error = 0); + ///< pass ENOENT in the optional 'suppress_error' parameter /// if you don't want a warning in the log when the directory does not exist /// @returns 0 on success and -1 on failure. /// rename a file - static int rename(const std::string& filename, const std::string& newname, int supress_error = 0); + static int rename(const std::string& filename, const std::string& newname, int suppress_error = 0); ///< it will silently overwrite newname if it exists without returning an error + /// Posix guarantees that if newname already exists, then there will be no moment + /// in which for other processes newname does not exist. There is no such guarantee + /// under Windows at this time. It may do it in the same way but the used Windows API + /// does not make such guarantees. /// @returns 0 on success and -1 on failure. - // copy the contents of file from 'from' to 'to' filename + /// copy the contents of file from 'from' to 'to' filename static bool copy(const std::string& from, const std::string& to); ///< @returns true on success and false on failure. /// return the file stat structure for filename - static int stat(const std::string& filename, llstat* file_status, int supress_error = ENOENT); + static int stat(const std::string& filename, llstat* file_status, int suppress_error = ENOENT); ///< for compatibility with existing uses of LL_File::stat() we use ENOENT as default in the - /// optional 'supress_error' parameter to avoid spamming the log with warnings when the API + /// optional 'suppress_error' parameter to avoid spamming the log with warnings when the API /// is used to detect if a file exists /// @returns 0 on success and -1 on failure. /// get the file or directory attributes for filename - static unsigned short getattr(const std::string& filename, int supress_error = 0); + static unsigned short getattr(const std::string& filename, bool dontFollowSymLink = false, int suppress_error = ENOENT); ///< a more lightweight function on Windows to stat, that just returns the file attribute flags - /// pass ENOENT in the optional 'supress_error' parameter if you don't want a warning - /// in the log when the file or directory does not exist + /// dontFollowSymLinks set to true returns the attributes of the symlink if it is one, rather than resolving it + /// we pass by default ENOENT in the optional 'suppress_error' parameter to not spam the log with + /// warnings when the file or directory does not exist /// @returns 0 on failure and a st_mode value with either S_IFDIR or S_IFREG set otherwise /// together with the three access bits which under Windows only the write bit is relevant. @@ -140,6 +156,10 @@ public: static bool isfile(const std::string& filename); ///< @returns true if the path is for an existing file + /// check if filename is a symlink + static bool islink(const std::string& filename); + ///< @returns true if the path is pointing at a symlink + /// return a path to the temporary directory on the system static const char * tmpdir(); }; |