/* $Id$ */
/** @file
* IPRT - Symbolic Links, POSIX.
*/
/*
* Copyright (C) 2010-2011 Oracle Corporation
*
* This file is part of VirtualBox Open Source Edition (OSE), as
* available from http://www.virtualbox.org. This file is free software;
* you can redistribute it and/or modify it under the terms of the GNU
* General Public License (GPL) as published by the Free Software
* Foundation, in version 2 as it comes in the "COPYING" file of the
* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
*
* The contents of this file may alternatively be used under the terms
* of the Common Development and Distribution License Version 1.0
* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
* VirtualBox OSE distribution, in which case the provisions of the
* CDDL are applicable instead of those of the GPL.
*
* You may elect to license modified versions of this file under the
* terms and conditions of either the GPL or the CDDL or both.
*/
/*******************************************************************************
* Header Files *
*******************************************************************************/
#define LOG_GROUP RTLOGGROUP_SYMLINK
#include <errno.h>
#include <sys/stat.h>
#include <unistd.h>
#include <iprt/symlink.h>
#include <iprt/assert.h>
#include <iprt/err.h>
#include <iprt/log.h>
#include <iprt/mem.h>
#include <iprt/string.h>
#include "internal/path.h"
RTDECL(bool) RTSymlinkExists(const char *pszSymlink)
{
bool fRc = false;
char const *pszNativeSymlink;
int rc = rtPathToNative(&pszNativeSymlink, pszSymlink, NULL);
if (RT_SUCCESS(rc))
{
struct stat s;
fRc = !lstat(pszNativeSymlink, &s)
&& S_ISLNK(s.st_mode);
rtPathFreeNative(pszNativeSymlink, pszSymlink);
}
LogFlow(("RTSymlinkExists(%p={%s}): returns %RTbool\n", pszSymlink, pszSymlink, fRc));
return fRc;
}
RTDECL(bool) RTSymlinkIsDangling(const char *pszSymlink)
{
bool fRc = false;
char const *pszNativeSymlink;
int rc = rtPathToNative(&pszNativeSymlink, pszSymlink, NULL);
if (RT_SUCCESS(rc))
{
struct stat s;
fRc = !lstat(pszNativeSymlink, &s)
&& S_ISLNK(s.st_mode);
if (fRc)
{
errno = 0;
fRc = stat(pszNativeSymlink, &s) != 0
&& ( errno == ENOENT
|| errno == ENOTDIR
|| errno == ELOOP);
}
rtPathFreeNative(pszNativeSymlink, pszSymlink);
}
LogFlow(("RTSymlinkIsDangling(%p={%s}): returns %RTbool\n", pszSymlink, pszSymlink, fRc));
return fRc;
}
RTDECL(int) RTSymlinkCreate(const char *pszSymlink, const char *pszTarget, RTSYMLINKTYPE enmType, uint32_t fCreate)
{
/*
* Validate the input.
*/
AssertReturn(enmType > RTSYMLINKTYPE_INVALID && enmType < RTSYMLINKTYPE_END, VERR_INVALID_PARAMETER);
AssertPtrReturn(pszSymlink, VERR_INVALID_POINTER);
AssertPtrReturn(pszTarget, VERR_INVALID_POINTER);
/*
* Convert the paths.
*/
char const *pszNativeSymlink;
int rc = rtPathToNative(&pszNativeSymlink, pszSymlink, NULL);
if (RT_SUCCESS(rc))
{
const char *pszNativeTarget;
rc = rtPathToNative(&pszNativeTarget, pszTarget, NULL);
if (RT_SUCCESS(rc))
{
/*
* Create the link.
*/
if (symlink(pszNativeTarget, pszNativeSymlink) == 0)
rc = VINF_SUCCESS;
else
rc = RTErrConvertFromErrno(errno);
rtPathFreeNative(pszNativeTarget, pszTarget);
}
rtPathFreeNative(pszNativeSymlink, pszSymlink);
}
LogFlow(("RTSymlinkCreate(%p={%s}, %p={%s}, %d, %#x): returns %Rrc\n", pszSymlink, pszSymlink, pszTarget, pszTarget, enmType, fCreate, rc));
return rc;
}
RTDECL(int) RTSymlinkDelete(const char *pszSymlink, uint32_t fDelete)
{
char const *pszNativeSymlink;
int rc = rtPathToNative(&pszNativeSymlink, pszSymlink, NULL);
if (RT_SUCCESS(rc))
{
struct stat s;
if (!lstat(pszNativeSymlink, &s))
{
if (S_ISLNK(s.st_mode))
{
if (unlink(pszNativeSymlink) == 0)
rc = VINF_SUCCESS;
else
rc = RTErrConvertFromErrno(errno);
}
else
rc = VERR_NOT_SYMLINK;
}
else
rc = RTErrConvertFromErrno(errno);
rtPathFreeNative(pszNativeSymlink, pszSymlink);
}
LogFlow(("RTSymlinkDelete(%p={%s}, #%x): returns %Rrc\n", pszSymlink, pszSymlink, fDelete, rc));
return rc;
}
RTDECL(int) RTSymlinkRead(const char *pszSymlink, char *pszTarget, size_t cbTarget, uint32_t fRead)
{
char *pszMyTarget;
int rc = RTSymlinkReadA(pszSymlink, &pszMyTarget);
if (RT_SUCCESS(rc))
{
rc = RTStrCopy(pszTarget, cbTarget, pszMyTarget);
RTStrFree(pszMyTarget);
}
LogFlow(("RTSymlinkRead(%p={%s}): returns %Rrc\n", pszSymlink, pszSymlink, rc));
return rc;
}
RTDECL(int) RTSymlinkReadA(const char *pszSymlink, char **ppszTarget)
{
AssertPtr(ppszTarget);
char const *pszNativeSymlink;
int rc = rtPathToNative(&pszNativeSymlink, pszSymlink, NULL);
if (RT_SUCCESS(rc))
{
/* Guess the initial buffer size. */
ssize_t cbBuf;
struct stat s;
if (!lstat(pszNativeSymlink, &s))
cbBuf = RT_MIN(RT_ALIGN_Z(s.st_size, 64), 64);
else
cbBuf = 1024;
/* Read loop that grows the buffer. */
char *pszBuf = NULL;
for (;;)
{
RTMemTmpFree(pszBuf);
pszBuf = (char *)RTMemTmpAlloc(cbBuf);
if (pszBuf)
{
ssize_t cbReturned = readlink(pszNativeSymlink, pszBuf, cbBuf);
if (cbReturned >= cbBuf)
{
/* Increase the buffer size and try again */
cbBuf *= 2;
continue;
}
if (cbReturned > 0)
{
pszBuf[cbReturned] = '\0';
rc = rtPathFromNativeDup(ppszTarget, pszBuf, pszSymlink);
}
else if (errno == EINVAL)
rc = VERR_NOT_SYMLINK;
else
rc = RTErrConvertFromErrno(errno);
}
else
rc = VERR_NO_TMP_MEMORY;
break;
} /* for loop */
RTMemTmpFree(pszBuf);
rtPathFreeNative(pszNativeSymlink, pszSymlink);
}
if (RT_SUCCESS(rc))
LogFlow(("RTSymlinkReadA(%p={%s},%p): returns %Rrc *ppszTarget=%p:{%s}\n", pszSymlink, pszSymlink, ppszTarget, rc, *ppszTarget, *ppszTarget));
else
LogFlow(("RTSymlinkReadA(%p={%s},%p): returns %Rrc\n", pszSymlink, pszSymlink, ppszTarget, rc));
return rc;
}