mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-12-13 18:27:35 +00:00
97 lines
2.8 KiB
C++
97 lines
2.8 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
|
|
* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
#if defined(XP_UNIX)
|
|
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#elif defined(XP_WIN)
|
|
#include <windows.h>
|
|
#elif defined(XP_OS2)
|
|
#define INCL_DOSFILEMGR
|
|
#include <os2.h>
|
|
#endif
|
|
|
|
#include "nscore.h"
|
|
#include "private/pprio.h"
|
|
#include "mozilla/FileUtils.h"
|
|
|
|
bool
|
|
mozilla::fallocate(PRFileDesc *aFD, int64_t aLength)
|
|
{
|
|
#if defined(HAVE_POSIX_FALLOCATE)
|
|
return posix_fallocate(PR_FileDesc2NativeHandle(aFD), 0, aLength) == 0;
|
|
#elif defined(XP_WIN)
|
|
int64_t oldpos = PR_Seek64(aFD, 0, PR_SEEK_CUR);
|
|
if (oldpos == -1)
|
|
return false;
|
|
|
|
if (PR_Seek64(aFD, aLength, PR_SEEK_SET) != aLength)
|
|
return false;
|
|
|
|
bool retval = (0 != SetEndOfFile((HANDLE)PR_FileDesc2NativeHandle(aFD)));
|
|
|
|
PR_Seek64(aFD, oldpos, PR_SEEK_SET);
|
|
return retval;
|
|
#elif defined(XP_OS2)
|
|
return aLength <= UINT32_MAX
|
|
&& 0 == DosSetFileSize(PR_FileDesc2NativeHandle(aFD), (uint32_t)aLength);
|
|
#elif defined(XP_MACOSX)
|
|
int fd = PR_FileDesc2NativeHandle(aFD);
|
|
fstore_t store = {F_ALLOCATECONTIG, F_PEOFPOSMODE, 0, aLength};
|
|
// Try to get a continous chunk of disk space
|
|
int ret = fcntl(fd, F_PREALLOCATE, &store);
|
|
if (-1 == ret) {
|
|
// OK, perhaps we are too fragmented, allocate non-continuous
|
|
store.fst_flags = F_ALLOCATEALL;
|
|
ret = fcntl(fd, F_PREALLOCATE, &store);
|
|
if (-1 == ret)
|
|
return false;
|
|
}
|
|
return 0 == ftruncate(fd, aLength);
|
|
#elif defined(XP_UNIX)
|
|
// The following is copied from fcntlSizeHint in sqlite
|
|
/* If the OS does not have posix_fallocate(), fake it. First use
|
|
** ftruncate() to set the file size, then write a single byte to
|
|
** the last byte in each block within the extended region. This
|
|
** is the same technique used by glibc to implement posix_fallocate()
|
|
** on systems that do not have a real fallocate() system call.
|
|
*/
|
|
int64_t oldpos = PR_Seek64(aFD, 0, PR_SEEK_CUR);
|
|
if (oldpos == -1)
|
|
return false;
|
|
|
|
struct stat buf;
|
|
int fd = PR_FileDesc2NativeHandle(aFD);
|
|
if (fstat(fd, &buf))
|
|
return false;
|
|
|
|
if (buf.st_size >= aLength)
|
|
return false;
|
|
|
|
const int nBlk = buf.st_blksize;
|
|
|
|
if (!nBlk)
|
|
return false;
|
|
|
|
if (ftruncate(fd, aLength))
|
|
return false;
|
|
|
|
int nWrite; // Return value from write()
|
|
int64_t iWrite = ((buf.st_size + 2 * nBlk - 1) / nBlk) * nBlk - 1; // Next offset to write to
|
|
while (iWrite < aLength) {
|
|
nWrite = 0;
|
|
if (PR_Seek64(aFD, iWrite, PR_SEEK_SET) == iWrite)
|
|
nWrite = PR_Write(aFD, "", 1);
|
|
if (nWrite != 1) break;
|
|
iWrite += nBlk;
|
|
}
|
|
|
|
PR_Seek64(aFD, oldpos, PR_SEEK_SET);
|
|
return nWrite == 1;
|
|
#endif
|
|
return false;
|
|
}
|