X-Git-Url: https://wimlib.net/git/?a=blobdiff_plain;f=src%2Fwin32_replacements.c;h=3082255033b3123cec78f70d965df4cb16e9c39c;hb=acabf4f97fdf439d6f95ff7af1fa952e91fa483b;hp=4e9df0aee8a5a538676176fd74a3d20819222513;hpb=da295f258b60e1593de305385c0669eac4b76644;p=wimlib diff --git a/src/win32_replacements.c b/src/win32_replacements.c index 4e9df0ae..30822550 100644 --- a/src/win32_replacements.c +++ b/src/win32_replacements.c @@ -30,11 +30,12 @@ #include #include -#include /* for PathMatchSpecW() */ +#include /* for _get_osfhandle() */ +#include + #include "wimlib/win32_common.h" #include "wimlib/assert.h" -#include "wimlib/file_io.h" #include "wimlib/glob.h" #include "wimlib/error.h" #include "wimlib/util.h" @@ -57,7 +58,7 @@ err: return -1; } -/* Use the Win32 API to get the number of processors */ +/* Use the Win32 API to get the number of processors. */ unsigned win32_get_number_of_processors(void) { @@ -66,6 +67,17 @@ win32_get_number_of_processors(void) return sysinfo.dwNumberOfProcessors; } +/* Use the Win32 API to get the amount of available memory. */ +u64 +win32_get_avail_memory(void) +{ + MEMORYSTATUSEX status = { + .dwLength = sizeof(status), + }; + GlobalMemoryStatusEx(&status); + return status.ullTotalPhys; +} + /* Replacement for POSIX-2008 realpath(). Warning: partial functionality only * (resolved_path must be NULL). Also I highly doubt that GetFullPathName * really does the right thing under all circumstances. */ @@ -88,7 +100,7 @@ realpath(const wchar_t *path, wchar_t *resolved_path) ret = GetFullPathNameW(path, ret, resolved_path, NULL); if (!ret) { err = GetLastError(); - free(resolved_path); + FREE(resolved_path); resolved_path = NULL; goto fail_win32; } @@ -99,64 +111,88 @@ out: return resolved_path; } -/* rename() on Windows fails if the destination file exists. And we need to - * make it work on wide characters. Fix it. */ +/* A quick hack to get reasonable rename() semantics on Windows, in particular + * deleting the destination file instead of failing with ERROR_FILE_EXISTS and + * working around any processes that may have the destination file open. + * + * Note: This is intended to be called when overwriting a regular file with an + * updated copy and is *not* a fully POSIX compliant rename(). For that you may + * wish to take a look at Cygwin's implementation, but be prepared... + * + * Return 0 on success, -1 on regular error, or 1 if the destination file was + * deleted but the source could not be renamed and therefore should not be + * deleted. + */ int -win32_rename_replacement(const wchar_t *oldpath, const wchar_t *newpath) +win32_rename_replacement(const wchar_t *srcpath, const wchar_t *dstpath) { - if (MoveFileExW(oldpath, newpath, MOVEFILE_REPLACE_EXISTING)) { - return 0; - } else { - set_errno_from_GetLastError(); - return -1; - } -} + wchar_t *tmpname; -/* Replacement for POSIX fnmatch() (partial functionality only) */ -int -fnmatch(const wchar_t *pattern, const wchar_t *string, int flags) -{ - if (PathMatchSpecW(string, pattern)) + /* Normally, MoveFileExW() with the MOVEFILE_REPLACE_EXISTING flag does + * what we want. */ + + if (MoveFileExW(srcpath, dstpath, MOVEFILE_REPLACE_EXISTING)) return 0; - else - return FNM_NOMATCH; -} -/* truncate() replacement */ -int -win32_truncate_replacement(const wchar_t *path, off_t size) -{ - DWORD err = NO_ERROR; - LARGE_INTEGER liOffset; + /* MoveFileExW() failed. One way this can happen is if any process has + * the destination file open, in which case ERROR_ACCESS_DENIED is + * produced. This can commonly happen if there is a backup or antivirus + * program monitoring or scanning the files. This behavior is very + * different from the behavior of POSIX rename(), which simply unlinks + * the destination file and allows other processes to keep it open! */ - HANDLE h = win32_open_existing_file(path, GENERIC_WRITE); - if (h == INVALID_HANDLE_VALUE) - goto fail; + if (GetLastError() != ERROR_ACCESS_DENIED) + goto err_set_errno; + + /* We can work around the above-mentioned problem by renaming the + * destination file to yet another temporary file, then "deleting" it, + * which on Windows will in fact not actually delete it immediately but + * rather mark it for deletion when the last handle to it is closed. */ + { + static const wchar_t orig_suffix[5] = L".orig"; + const size_t num_rand_chars = 9; + wchar_t *p; + + size_t dstlen = wcslen(dstpath); + + tmpname = alloca(sizeof(wchar_t) * + (dstlen + ARRAY_LEN(orig_suffix) + num_rand_chars + 1)); + p = tmpname; + p = wmempcpy(p, dstpath, dstlen); + p = wmempcpy(p, orig_suffix, ARRAY_LEN(orig_suffix)); + randomize_char_array_with_alnum(p, num_rand_chars); + p += num_rand_chars; + *p = L'\0'; + } + + if (!MoveFile(dstpath, tmpname)) + goto err_set_errno; - liOffset.QuadPart = size; - if (!SetFilePointerEx(h, liOffset, NULL, FILE_BEGIN)) - goto fail_close_handle; + if (!DeleteFile(tmpname)) { + set_errno_from_GetLastError(); + WARNING_WITH_ERRNO("Failed to delete original file " + "(moved to \"%ls\")", tmpname); + } + + if (!MoveFile(srcpath, dstpath)) { + set_errno_from_GetLastError(); + WARNING_WITH_ERRNO("Atomic semantics not respected in " + "failed rename() (new file is at \"%ls\")", + srcpath); + return 1; + } - if (!SetEndOfFile(h)) - goto fail_close_handle; - CloseHandle(h); return 0; -fail_close_handle: - err = GetLastError(); - CloseHandle(h); -fail: - if (err == NO_ERROR) - err = GetLastError(); - set_errno_from_win32_error(err); +err_set_errno: + set_errno_from_GetLastError(); return -1; } - /* This really could be replaced with _wcserror_s, but this doesn't seem to * actually be available in MSVCRT.DLL on Windows XP (perhaps it's statically * linked in by Visual Studio...?). */ -extern int +int win32_strerror_r_replacement(int errnum, wchar_t *buf, size_t buflen) { static pthread_mutex_t strerror_lock = PTHREAD_MUTEX_INITIALIZER; @@ -234,61 +270,6 @@ pwrite(int fd, const void *buf, size_t count, off_t offset) return do_pread_or_pwrite(fd, (void*)buf, count, offset, true); } -/* Dumb Windows implementation of writev(). It writes the vectors one at a - * time. */ -ssize_t writev(int fd, const struct iovec *iov, int iovcnt) -{ - ssize_t total_bytes_written = 0; - - if (iovcnt <= 0) { - errno = EINVAL; - return -1; - } - for (int i = 0; i < iovcnt; i++) { - ssize_t bytes_written; - - bytes_written = write(fd, iov[i].iov_base, iov[i].iov_len); - if (bytes_written >= 0) - total_bytes_written += bytes_written; - if (bytes_written != iov[i].iov_len) { - if (total_bytes_written == 0) - total_bytes_written = -1; - break; - } - } - return total_bytes_written; -} - -int -win32_get_file_and_vol_ids(const wchar_t *path, u64 *ino_ret, u64 *dev_ret) -{ - HANDLE h; - BY_HANDLE_FILE_INFORMATION file_info; - int ret; - DWORD err; - - h = win32_open_existing_file(path, FILE_READ_ATTRIBUTES); - if (h == INVALID_HANDLE_VALUE) { - ret = WIMLIB_ERR_OPEN; - goto out; - } - - if (!GetFileInformationByHandle(h, &file_info)) { - ret = WIMLIB_ERR_STAT; - } else { - *ino_ret = ((u64)file_info.nFileIndexHigh << 32) | - (u64)file_info.nFileIndexLow; - *dev_ret = file_info.dwVolumeSerialNumber; - ret = 0; - } - err = GetLastError(); - CloseHandle(h); - SetLastError(err); -out: - set_errno_from_GetLastError(); - return ret; -} - /* Replacement for glob() in Windows native builds that operates on wide * characters. */ int @@ -301,6 +282,7 @@ win32_wglob(const wchar_t *pattern, int flags, HANDLE hFind; int ret; size_t nspaces; + int errno_save; const wchar_t *backslash, *end_slash; size_t prefix_len; @@ -330,9 +312,7 @@ win32_wglob(const wchar_t *pattern, int flags, errno = 0; return GLOB_NOMATCH; } else { - /* The other possible error codes for FindFirstFile() - * are undocumented. */ - errno = EIO; + set_errno_from_win32_error(err); return GLOB_ABORTED; } } @@ -366,22 +346,21 @@ win32_wglob(const wchar_t *pattern, int flags, } while (FindNextFileW(hFind, &dat)); err = GetLastError(); CloseHandle(hFind); - if (err == ERROR_NO_MORE_FILES) { - errno = 0; - return 0; - } else { - /* Other possible error codes for FindNextFile() are - * undocumented */ - errno = EIO; + if (err != ERROR_NO_MORE_FILES) { + set_errno_from_win32_error(err); ret = GLOB_ABORTED; goto fail_globfree; } + return 0; + oom: CloseHandle(hFind); errno = ENOMEM; ret = GLOB_NOSPACE; fail_globfree: + errno_save = errno; globfree(pglob); + errno = errno_save; return ret; } @@ -390,8 +369,37 @@ globfree(glob_t *pglob) { size_t i; for (i = 0; i < pglob->gl_pathc; i++) - free(pglob->gl_pathv[i]); - free(pglob->gl_pathv); + FREE(pglob->gl_pathv[i]); + FREE(pglob->gl_pathv); +} + +/* Replacement for fopen(path, "a") that doesn't prevent other processes from + * reading the file */ +FILE * +win32_open_logfile(const wchar_t *path) +{ + HANDLE h; + int fd; + FILE *fp; + + h = CreateFile(path, FILE_APPEND_DATA, FILE_SHARE_VALID_FLAGS, + NULL, OPEN_ALWAYS, 0, NULL); + if (h == INVALID_HANDLE_VALUE) + return NULL; + + fd = _open_osfhandle((intptr_t)h, O_APPEND); + if (fd < 0) { + CloseHandle(h); + return NULL; + } + + fp = fdopen(fd, "a"); + if (!fp) { + close(fd); + return NULL; + } + + return fp; } #endif /* __WIN32__ */