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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 16:58:41 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 16:58:41 +0000
commite1908ae95dd4c9d19ee4dfabfc8bf8a7f85943fe (patch)
treef5cc731bedcac0fb7fe14d952e4581e749f8bb87 /lib/ftruncate.c
parentInitial commit. (diff)
downloadcoreutils-upstream.tar.xz
coreutils-upstream.zip
Adding upstream version 9.4.upstream/9.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/ftruncate.c')
-rw-r--r--lib/ftruncate.c195
1 files changed, 195 insertions, 0 deletions
diff --git a/lib/ftruncate.c b/lib/ftruncate.c
new file mode 100644
index 0000000..b662523
--- /dev/null
+++ b/lib/ftruncate.c
@@ -0,0 +1,195 @@
+/* ftruncate emulations for native Windows.
+ Copyright (C) 1992-2023 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, 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/>. */
+
+#include <config.h>
+
+/* Specification. */
+#include <unistd.h>
+
+#if HAVE__CHSIZE
+/* A native Windows platform. */
+
+# include <errno.h>
+
+# if _GL_WINDOWS_64_BIT_OFF_T
+
+/* Large File Support: off_t is 64-bit, but _chsize() takes only a 32-bit
+ argument. So, define a 64-bit safe SetFileSize function ourselves. */
+
+/* Ensure that <windows.h> declares GetFileSizeEx. */
+# if !defined _WIN32_WINNT || (_WIN32_WINNT < _WIN32_WINNT_WIN2K)
+# undef _WIN32_WINNT
+# define _WIN32_WINNT _WIN32_WINNT_WIN2K
+# endif
+
+/* Get declarations of the native Windows API functions. */
+# define WIN32_LEAN_AND_MEAN
+# include <windows.h>
+
+/* Get _get_osfhandle. */
+# if GNULIB_MSVC_NOTHROW
+# include "msvc-nothrow.h"
+# else
+# include <io.h>
+# endif
+
+static BOOL
+SetFileSize (HANDLE h, LONGLONG size)
+{
+ LARGE_INTEGER old_size;
+
+ if (!GetFileSizeEx (h, &old_size))
+ return FALSE;
+
+ if (size != old_size.QuadPart)
+ {
+ /* Duplicate the handle, so we are free to modify its file position. */
+ HANDLE curr_process = GetCurrentProcess ();
+ HANDLE tmph;
+
+ if (!DuplicateHandle (curr_process, /* SourceProcessHandle */
+ h, /* SourceHandle */
+ curr_process, /* TargetProcessHandle */
+ (PHANDLE) &tmph, /* TargetHandle */
+ (DWORD) 0, /* DesiredAccess */
+ FALSE, /* InheritHandle */
+ DUPLICATE_SAME_ACCESS)) /* Options */
+ return FALSE;
+
+ if (size < old_size.QuadPart)
+ {
+ /* Reduce the size. */
+ LONG size_hi = (LONG) (size >> 32);
+ if (SetFilePointer (tmph, (LONG) size, &size_hi, FILE_BEGIN)
+ == INVALID_SET_FILE_POINTER
+ && GetLastError() != NO_ERROR)
+ {
+ CloseHandle (tmph);
+ return FALSE;
+ }
+ if (!SetEndOfFile (tmph))
+ {
+ CloseHandle (tmph);
+ return FALSE;
+ }
+ }
+ else
+ {
+ /* Increase the size by adding zero bytes at the end. */
+ static char zero_bytes[1024];
+ LONG pos_hi = 0;
+ LONG pos_lo = SetFilePointer (tmph, (LONG) 0, &pos_hi, FILE_END);
+ LONGLONG pos;
+ if (pos_lo == INVALID_SET_FILE_POINTER
+ && GetLastError() != NO_ERROR)
+ {
+ CloseHandle (tmph);
+ return FALSE;
+ }
+ pos = ((LONGLONG) pos_hi << 32) | (ULONGLONG) (ULONG) pos_lo;
+ while (pos < size)
+ {
+ DWORD written;
+ LONGLONG count = size - pos;
+ if (count > sizeof (zero_bytes))
+ count = sizeof (zero_bytes);
+ if (!WriteFile (tmph, zero_bytes, (DWORD) count, &written, NULL)
+ || written == 0)
+ {
+ CloseHandle (tmph);
+ return FALSE;
+ }
+ pos += (ULONGLONG) (ULONG) written;
+ }
+ }
+ /* Close the handle. */
+ CloseHandle (tmph);
+ }
+ return TRUE;
+}
+
+int
+ftruncate (int fd, off_t length)
+{
+ HANDLE handle = (HANDLE) _get_osfhandle (fd);
+
+ if (handle == INVALID_HANDLE_VALUE)
+ {
+ errno = EBADF;
+ return -1;
+ }
+ if (length < 0)
+ {
+ errno = EINVAL;
+ return -1;
+ }
+ if (!SetFileSize (handle, length))
+ {
+ switch (GetLastError ())
+ {
+ case ERROR_ACCESS_DENIED:
+ errno = EACCES;
+ break;
+ case ERROR_HANDLE_DISK_FULL:
+ case ERROR_DISK_FULL:
+ case ERROR_DISK_TOO_FRAGMENTED:
+ errno = ENOSPC;
+ break;
+ default:
+ errno = EIO;
+ break;
+ }
+ return -1;
+ }
+ return 0;
+}
+
+# else
+
+# include <io.h>
+
+# if HAVE_MSVC_INVALID_PARAMETER_HANDLER
+# include "msvc-inval.h"
+static int
+chsize_nothrow (int fd, long length)
+{
+ int result;
+
+ TRY_MSVC_INVAL
+ {
+ result = _chsize (fd, length);
+ }
+ CATCH_MSVC_INVAL
+ {
+ result = -1;
+ errno = EBADF;
+ }
+ DONE_MSVC_INVAL;
+
+ return result;
+}
+# else
+# define chsize_nothrow _chsize
+# endif
+
+int
+ftruncate (int fd, off_t length)
+{
+ return chsize_nothrow (fd, length);
+}
+
+# endif
+#endif