diff options
Diffstat (limited to '')
| -rw-r--r-- | gl/lib/utime.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/gl/lib/utime.c b/gl/lib/utime.c new file mode 100644 index 0000000..c35eb16 --- /dev/null +++ b/gl/lib/utime.c @@ -0,0 +1,262 @@ +/* Work around platform bugs in utime. + Copyright (C) 2017-2020 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* Written by Bruno Haible. */ + +#include <config.h> + +/* Specification. */ +#include <utime.h> + +#if defined _WIN32 && ! defined __CYGWIN__ + +# include <errno.h> +# include <stdbool.h> +# include <windows.h> +# include "filename.h" +# include "malloca.h" + +/* Don't assume that UNICODE is not defined. */ +# undef CreateFile +# define CreateFile CreateFileA +# undef GetFileAttributes +# define GetFileAttributes GetFileAttributesA + +int +_gl_utimens_windows (const char *name, struct timespec ts[2]) +{ + /* POSIX <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13> + specifies: "More than two leading <slash> characters shall be treated as + a single <slash> character." */ + if (ISSLASH (name[0]) && ISSLASH (name[1]) && ISSLASH (name[2])) + { + name += 2; + while (ISSLASH (name[1])) + name++; + } + + size_t len = strlen (name); + size_t drive_prefix_len = (HAS_DEVICE (name) ? 2 : 0); + + /* Remove trailing slashes (except the very first one, at position + drive_prefix_len), but remember their presence. */ + size_t rlen; + bool check_dir = false; + + rlen = len; + while (rlen > drive_prefix_len && ISSLASH (name[rlen-1])) + { + check_dir = true; + if (rlen == drive_prefix_len + 1) + break; + rlen--; + } + + const char *rname; + char *malloca_rname; + if (rlen == len) + { + rname = name; + malloca_rname = NULL; + } + else + { + malloca_rname = malloca (rlen + 1); + if (malloca_rname == NULL) + { + errno = ENOMEM; + return -1; + } + memcpy (malloca_rname, name, rlen); + malloca_rname[rlen] = '\0'; + rname = malloca_rname; + } + + DWORD error; + + /* Open a handle to the file. + CreateFile + <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-createfilea> + <https://docs.microsoft.com/en-us/windows/desktop/FileIO/creating-and-opening-files> */ + HANDLE handle = + CreateFile (rname, + FILE_READ_ATTRIBUTES | FILE_WRITE_ATTRIBUTES, + FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, + NULL, + OPEN_EXISTING, + /* FILE_FLAG_POSIX_SEMANTICS (treat file names that differ only + in case as different) makes sense only when applied to *all* + filesystem operations. */ + FILE_FLAG_BACKUP_SEMANTICS /* | FILE_FLAG_POSIX_SEMANTICS */, + NULL); + if (handle == INVALID_HANDLE_VALUE) + { + error = GetLastError (); + goto failed; + } + + if (check_dir) + { + /* GetFileAttributes + <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-getfileattributesa> */ + DWORD attributes = GetFileAttributes (rname); + if (attributes == INVALID_FILE_ATTRIBUTES) + { + error = GetLastError (); + CloseHandle (handle); + goto failed; + } + if ((attributes & FILE_ATTRIBUTE_DIRECTORY) == 0) + { + CloseHandle (handle); + if (malloca_rname != NULL) + freea (malloca_rname); + errno = ENOTDIR; + return -1; + } + } + + { + /* Use SetFileTime(). See + <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-setfiletime> + <https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ns-minwinbase-filetime> */ + FILETIME last_access_time; + FILETIME last_write_time; + if (ts == NULL) + { + /* GetSystemTimeAsFileTime is the same as + GetSystemTime followed by SystemTimeToFileTime. + <https://docs.microsoft.com/en-us/windows/desktop/api/sysinfoapi/nf-sysinfoapi-getsystemtimeasfiletime>. + It would be overkill to use + GetSystemTimePreciseAsFileTime + <https://docs.microsoft.com/en-us/windows/desktop/api/sysinfoapi/nf-sysinfoapi-getsystemtimepreciseasfiletime>. */ + FILETIME current_time; + GetSystemTimeAsFileTime (¤t_time); + last_access_time = current_time; + last_write_time = current_time; + } + else + { + { + ULONGLONG time_since_16010101 = + (ULONGLONG) ts[0].tv_sec * 10000000 + ts[0].tv_nsec / 100 + 116444736000000000LL; + last_access_time.dwLowDateTime = (DWORD) time_since_16010101; + last_access_time.dwHighDateTime = time_since_16010101 >> 32; + } + { + ULONGLONG time_since_16010101 = + (ULONGLONG) ts[1].tv_sec * 10000000 + ts[1].tv_nsec / 100 + 116444736000000000LL; + last_write_time.dwLowDateTime = (DWORD) time_since_16010101; + last_write_time.dwHighDateTime = time_since_16010101 >> 32; + } + } + if (SetFileTime (handle, NULL, &last_access_time, &last_write_time)) + { + CloseHandle (handle); + if (malloca_rname != NULL) + freea (malloca_rname); + return 0; + } + else + { + #if 0 + DWORD sft_error = GetLastError (); + fprintf (stderr, "utimens SetFileTime error 0x%x\n", (unsigned int) sft_error); + #endif + CloseHandle (handle); + if (malloca_rname != NULL) + freea (malloca_rname); + errno = EINVAL; + return -1; + } + } + + failed: + { + #if 0 + fprintf (stderr, "utimens CreateFile/GetFileAttributes error 0x%x\n", (unsigned int) error); + #endif + if (malloca_rname != NULL) + freea (malloca_rname); + + switch (error) + { + /* Some of these errors probably cannot happen with the specific flags + that we pass to CreateFile. But who knows... */ + case ERROR_FILE_NOT_FOUND: /* The last component of rname does not exist. */ + case ERROR_PATH_NOT_FOUND: /* Some directory component in rname does not exist. */ + case ERROR_BAD_PATHNAME: /* rname is such as '\\server'. */ + case ERROR_BAD_NETPATH: /* rname is such as '\\nonexistentserver\share'. */ + case ERROR_BAD_NET_NAME: /* rname is such as '\\server\nonexistentshare'. */ + case ERROR_INVALID_NAME: /* rname contains wildcards, misplaced colon, etc. */ + case ERROR_DIRECTORY: + errno = ENOENT; + break; + + case ERROR_ACCESS_DENIED: /* rname is such as 'C:\System Volume Information\foo'. */ + case ERROR_SHARING_VIOLATION: /* rname is such as 'C:\pagefile.sys'. */ + errno = (ts != NULL ? EPERM : EACCES); + break; + + case ERROR_OUTOFMEMORY: + errno = ENOMEM; + break; + + case ERROR_WRITE_PROTECT: + errno = EROFS; + break; + + case ERROR_WRITE_FAULT: + case ERROR_READ_FAULT: + case ERROR_GEN_FAILURE: + errno = EIO; + break; + + case ERROR_BUFFER_OVERFLOW: + case ERROR_FILENAME_EXCED_RANGE: + errno = ENAMETOOLONG; + break; + + case ERROR_DELETE_PENDING: /* XXX map to EACCES or EPERM? */ + errno = EPERM; + break; + + default: + errno = EINVAL; + break; + } + + return -1; + } +} + +int +utime (const char *name, const struct utimbuf *ts) +{ + if (ts == NULL) + return _gl_utimens_windows (name, NULL); + else + { + struct timespec ts_with_nanoseconds[2]; + ts_with_nanoseconds[0].tv_sec = ts->actime; + ts_with_nanoseconds[0].tv_nsec = 0; + ts_with_nanoseconds[1].tv_sec = ts->modtime; + ts_with_nanoseconds[1].tv_nsec = 0; + return _gl_utimens_windows (name, ts_with_nanoseconds); + } +} + +#endif |