Imported from /home/lorry/working-area/delta_VirtualBox/VirtualBox-4.3.10.tar.bz2.HEADVirtualBox-4.3.10master

11 files changed, 82 insertions, 59 deletions

diff --git a/src/VBox/HostServices/SharedFolders/mappings.cpp b/src/VBox/HostServices/SharedFolders/mappings.cpp
index 166dd049..30310909 100644
--- a/src/VBox/HostServices/SharedFolders/mappings.cpp
+++ b/src/VBox/HostServices/SharedFolders/mappings.cpp
@@ -3,7 +3,7 @@
  */
 
 /*
- * Copyright (C) 2006-2007 Oracle Corporation
+ * Copyright (C) 2006-2012 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
  * available from http://www.virtualbox.org. This file is free software;
@@ -191,7 +191,7 @@ void testMappingsAdd(RTTEST hTest)
  * We are always executed from one specific HGCM thread. So thread safe.
  */
 int vbsfMappingsAdd(PSHFLSTRING pFolderName, PSHFLSTRING pMapName,
-                    bool fWritable, bool fAutoMount, bool fSymlinksCreate)
+                    bool fWritable, bool fAutoMount, bool fSymlinksCreate, bool fMissing)
 {
     unsigned i;
 
@@ -236,6 +236,7 @@ int vbsfMappingsAdd(PSHFLSTRING pFolderName, PSHFLSTRING pMapName,
             FolderMapping[i].fWritable       = fWritable;
             FolderMapping[i].fAutoMount      = fAutoMount;
             FolderMapping[i].fSymlinksCreate = fSymlinksCreate;
+            FolderMapping[i].fMissing        = fMissing;
 
             /* Check if the host file system is case sensitive */
             RTFSPROPERTIES prop;
@@ -317,6 +318,8 @@ const char* vbsfMappingsQueryHostRoot(SHFLROOT root)
 {
     MAPPING *pFolderMapping = vbsfMappingGetByRoot(root);
     AssertReturn(pFolderMapping, NULL);
+    if (pFolderMapping->fMissing)
+        return NULL;
     return pFolderMapping->pszFolderName;
 }
 
@@ -459,7 +462,8 @@ int vbsfMappingsQueryWritable(PSHFLCLIENTDATA pClient, SHFLROOT root, bool *fWri
     MAPPING *pFolderMapping = vbsfMappingGetByRoot(root);
     AssertReturn(pFolderMapping, VERR_INVALID_PARAMETER);
 
-    if (pFolderMapping->fValid == true)
+    if (   pFolderMapping->fValid
+        && !pFolderMapping->fMissing)
         *fWritable = pFolderMapping->fWritable;
     else
         rc = VERR_FILE_NOT_FOUND;
diff --git a/src/VBox/HostServices/SharedFolders/mappings.h b/src/VBox/HostServices/SharedFolders/mappings.h
index f920e617..c0a2989f 100644
--- a/src/VBox/HostServices/SharedFolders/mappings.h
+++ b/src/VBox/HostServices/SharedFolders/mappings.h
@@ -3,7 +3,7 @@
  */
 
 /*
- * Copyright (C) 2006-2010 Oracle Corporation
+ * Copyright (C) 2006-2012 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
  * available from http://www.virtualbox.org. This file is free software;
@@ -31,6 +31,8 @@ typedef struct
     bool        fWritable;            /**< folder is writable for the guest */
     bool        fAutoMount;           /**< folder will be auto-mounted by the guest */
     bool        fSymlinksCreate;      /**< guest is able to create symlinks */
+    bool        fMissing;             /**< mapping not invalid but host path does not exist.
+                                           Any guest operation on such a folder fails! */
 } MAPPING;
 /** Pointer to a MAPPING structure. */
 typedef MAPPING *PMAPPING;
@@ -40,7 +42,7 @@ void vbsfMappingInit(void);
 bool vbsfMappingQuery(uint32_t iMapping, PMAPPING *pMapping);
 
 int vbsfMappingsAdd(PSHFLSTRING pFolderName, PSHFLSTRING pMapName,
-                    bool fWritable, bool fAutoMount, bool fCreateSymlinks);
+                    bool fWritable, bool fAutoMount, bool fCreateSymlinks, bool fMissing);
 int vbsfMappingsRemove(PSHFLSTRING pMapName);
 
 int vbsfMappingsQuery(PSHFLCLIENTDATA pClient, PSHFLMAPPING pMappings, uint32_t *pcMappings);
diff --git a/src/VBox/HostServices/SharedFolders/service.cpp b/src/VBox/HostServices/SharedFolders/service.cpp
index bc390aeb..0c724f33 100644
--- a/src/VBox/HostServices/SharedFolders/service.cpp
+++ b/src/VBox/HostServices/SharedFolders/service.cpp
@@ -3,7 +3,7 @@
  */
 
 /*
- * Copyright (C) 2006-2010 Oracle Corporation
+ * Copyright (C) 2006-2012 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
  * available from http://www.virtualbox.org. This file is free software;
@@ -1313,18 +1313,20 @@ static DECLCALLBACK(int) svcHostCall (void *, uint32_t u32Function, uint32_t cPa
             }
             else
             {
-                LogRel(("    Host path '%ls', map name '%ls', %s, automount=%s, create_symlinks=%s\n",
+                LogRel(("    Host path '%ls', map name '%ls', %s, automount=%s, create_symlinks=%s, missing=%s\n",
                         ((SHFLSTRING *)paParms[0].u.pointer.addr)->String.ucs2,
                         ((SHFLSTRING *)paParms[1].u.pointer.addr)->String.ucs2,
                         RT_BOOL(fFlags & SHFL_ADD_MAPPING_F_WRITABLE) ? "writable" : "read-only",
                         RT_BOOL(fFlags & SHFL_ADD_MAPPING_F_AUTOMOUNT) ? "true" : "false",
-                        RT_BOOL(fFlags & SHFL_ADD_MAPPING_F_CREATE_SYMLINKS) ? "true" : "false"));
+                        RT_BOOL(fFlags & SHFL_ADD_MAPPING_F_CREATE_SYMLINKS) ? "true" : "false",
+                        RT_BOOL(fFlags & SHFL_ADD_MAPPING_F_MISSING) ? "true" : "false"));
 
                 /* Execute the function. */
                 rc = vbsfMappingsAdd(pFolderName, pMapName,
                                      RT_BOOL(fFlags & SHFL_ADD_MAPPING_F_WRITABLE),
                                      RT_BOOL(fFlags & SHFL_ADD_MAPPING_F_AUTOMOUNT),
-                                     RT_BOOL(fFlags & SHFL_ADD_MAPPING_F_CREATE_SYMLINKS));
+                                     RT_BOOL(fFlags & SHFL_ADD_MAPPING_F_CREATE_SYMLINKS),
+                                     RT_BOOL(fFlags & SHFL_ADD_MAPPING_F_MISSING));
                 if (RT_SUCCESS(rc))
                 {
                     /* Update parameters.*/
diff --git a/src/VBox/HostServices/SharedFolders/shflhandle.cpp b/src/VBox/HostServices/SharedFolders/shflhandle.cpp
index cd67057b..1a5f71bd 100644
--- a/src/VBox/HostServices/SharedFolders/shflhandle.cpp
+++ b/src/VBox/HostServices/SharedFolders/shflhandle.cpp
@@ -5,7 +5,7 @@
  */
 
 /*
- * Copyright (C) 2006-2007 Oracle Corporation
+ * Copyright (C) 2006-2011 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
  * available from http://www.virtualbox.org. This file is free software;
diff --git a/src/VBox/HostServices/SharedFolders/shflhandle.h b/src/VBox/HostServices/SharedFolders/shflhandle.h
index 625c0102..59638b91 100644
--- a/src/VBox/HostServices/SharedFolders/shflhandle.h
+++ b/src/VBox/HostServices/SharedFolders/shflhandle.h
@@ -5,7 +5,7 @@
  */
 
 /*
- * Copyright (C) 2006-2007 Oracle Corporation
+ * Copyright (C) 2006-2011 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
  * available from http://www.virtualbox.org. This file is free software;
diff --git a/src/VBox/HostServices/SharedFolders/testcase/Makefile.kmk b/src/VBox/HostServices/SharedFolders/testcase/Makefile.kmk
index a6f327ef..a2f6120d 100644
--- a/src/VBox/HostServices/SharedFolders/testcase/Makefile.kmk
+++ b/src/VBox/HostServices/SharedFolders/testcase/Makefile.kmk
@@ -54,12 +54,7 @@ tstShflCase_LIBS     = $(LIB_RUNTIME)
 # HGCM service testcase.
 #
 
-# As there are differences between the Windows build of the service and others,
-# we do an additional build with RT_OS_WINDOWS defined on non-Windows targets.
-PROGRAMS += \
-    tstSharedFolderService \
-    $(if $(eq $(KBUILD_TARGET),win),,tstSharedFolderService-win)
-
+PROGRAMS += tstSharedFolderService
 tstSharedFolderService_TEMPLATE = VBOXR3TSTEXE
 tstSharedFolderService_DEFS     = VBOX_WITH_HGCM UNITTEST
 tstSharedFolderService_INCS     = ..
@@ -73,6 +68,12 @@ tstSharedFolderService_LDFLAGS.darwin = \
 	-framework Carbon
 tstSharedFolderService_LIBS     = $(LIB_RUNTIME)
 
+if 0 # Cannot define two RT_OS_XXX macros!
+# As there are differences between the Windows build of the service and others,
+# we do an additional build with RT_OS_WINDOWS defined on non-Windows targets.
+PROGRAMS += \
+    tstSharedFolderService \
+    $(if $(eq $(KBUILD_TARGET),win),,tstSharedFolderService-win)
 tstSharedFolderService-win_TEMPLATE = $(tstSharedFolderService_TEMPLATE)
 tstSharedFolderService-win_DEFS     = \
     $(tstSharedFolderService_DEFS) \
@@ -82,6 +83,7 @@ tstSharedFolderService-win_SOURCES  = $(tstSharedFolderService_SOURCES)
 tstSharedFolderService-win_LDFLAGS.darwin = \
     $(tstSharedFolderService_LDFLAGS.darwin)
 tstSharedFolderService-win_LIBS     = $(tstSharedFolderService_LIBS)
+endif
 
 endif # VBOX_WITH_TESTCASES
 
diff --git a/src/VBox/HostServices/SharedFolders/testcase/tstSharedFolderService.cpp b/src/VBox/HostServices/SharedFolders/testcase/tstSharedFolderService.cpp
index b72e724b..1215090a 100644
--- a/src/VBox/HostServices/SharedFolders/testcase/tstSharedFolderService.cpp
+++ b/src/VBox/HostServices/SharedFolders/testcase/tstSharedFolderService.cpp
@@ -1,6 +1,5 @@
 /* $Id: tstSharedFolderService.cpp $ */
 /** @file
- *
  * Testcase for the shared folder service vbsf API.
  *
  * Note that this is still very threadbare (there is an awful lot which should
@@ -11,7 +10,7 @@
  */
 
 /*
- * Copyright (C) 2011 Oracle Corporation
+ * Copyright (C) 2011-2013 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
  * available from http://www.virtualbox.org. This file is free software;
@@ -39,17 +38,19 @@
 
 #include "teststubs.h"
 
+
 /******************************************************************************
 *   Global Variables                                                          *
 ******************************************************************************/
 static RTTEST g_hTest = NIL_RTTEST;
 
+
 /******************************************************************************
 *   Declarations                                                              *
 ******************************************************************************/
-
 extern "C" DECLCALLBACK(DECLEXPORT(int)) VBoxHGCMSvcLoad (VBOXHGCMSVCFNTABLE *ptable);
 
+
 /******************************************************************************
 *   Helpers                                                                   *
 ******************************************************************************/
@@ -102,14 +103,15 @@ static void bufferFromPath(void *pvDest, size_t cb, const char *pcszSrc)
 }
 
 #define ARRAY_FROM_PATH(a, b) \
-do { \
-    Assert((a) == (a)); /* Constant parameter */ \
-    Assert(sizeof((a)) > 0); \
-    bufferFromPath(a, sizeof(a), b); \
-} while(0)
+    do { \
+        Assert((a) == (a)); /* Constant parameter */ \
+        Assert(sizeof((a)) > 0); \
+        bufferFromPath(a, sizeof(a), b); \
+    } while (0)
+
 
 /******************************************************************************
-*   Stub functions                                                            *
+*   Stub functions and data                                                   *
 ******************************************************************************/
 
 static PRTDIR testRTDirClosepDir;
@@ -306,7 +308,7 @@ static uint64_t testRTFileSetFMode;
 extern int testRTFileSetMode(RTFILE File, RTFMODE fMode)
 {
  /* RTPrintf("%s: fMode=%llu\n", __PRETTY_FUNCTION__, LLUIFY(fMode)); */
-    testRTFileSetFMode = fMode; 
+    testRTFileSetFMode = fMode;
     return VINF_SUCCESS;
 }
 
@@ -369,7 +371,7 @@ extern int  testRTFileWrite(RTFILE File, const void *pvBuf, size_t cbToWrite,
         *pcbWritten = strlen(testRTFileWriteData) + 1;
     return VINF_SUCCESS;
 }
-                             
+
 extern int testRTFsQueryProperties(const char *pszFsPath,
                                       PRTFSPROPERTIES pProperties)
 {
@@ -383,7 +385,7 @@ extern int testRTFsQueryProperties(const char *pszFsPath,
 extern int testRTFsQuerySerial(const char *pszFsPath, uint32_t *pu32Serial)
 { RTPrintf("%s\n", __PRETTY_FUNCTION__); return 0; }
 extern int testRTFsQuerySizes(const char *pszFsPath, PRTFOFF pcbTotal,
-                                 RTFOFF *pcbFree, uint32_t *pcbBlock, 
+                                 RTFOFF *pcbFree, uint32_t *pcbBlock,
                                  uint32_t *pcbSector) { RTPrintf("%s\n", __PRETTY_FUNCTION__); return 0; }
 
 extern int testRTPathQueryInfoEx(const char *pszPath,
@@ -398,12 +400,13 @@ extern int testRTPathQueryInfoEx(const char *pszPath,
     return VINF_SUCCESS;
 }
 
-extern int testRTSymlinkDelete(const char *pszSymlink, uint32_t fDelete) 
+extern int testRTSymlinkDelete(const char *pszSymlink, uint32_t fDelete)
 { RTPrintf("%s\n", __PRETTY_FUNCTION__); return 0; }
 extern int testRTSymlinkRead(const char *pszSymlink, char *pszTarget,
                               size_t cbTarget, uint32_t fRead)
 { RTPrintf("%s\n", __PRETTY_FUNCTION__); return 0; }
 
+
 /******************************************************************************
 *   Tests                                                                     *
 ******************************************************************************/
@@ -484,13 +487,11 @@ struct TESTSHFLSTRING
 static void fillTestShflString(struct TESTSHFLSTRING *pDest,
                                const char *pcszSource)
 {
-    unsigned i;
-    
-    AssertRelease(  strlen(pcszSource) * 2 + 2 < sizeof(*pDest)
-                  - RT_UOFFSETOF(SHFLSTRING, String));
-    pDest->string.u16Size = (uint16_t)strlen(pcszSource) * 2 + 2;
-    pDest->string.u16Length = (uint16_t)strlen(pcszSource);
-    for (i = 0; i < strlen(pcszSource) + 1; ++i)
+    AssertRelease(  strlen(pcszSource) * 2 + 2
+                  < sizeof(*pDest) - RT_UOFFSETOF(SHFLSTRING, String));
+    pDest->string.u16Length = (uint16_t)(strlen(pcszSource) * sizeof(RTUTF16));
+    pDest->string.u16Size   = pDest->string.u16Length + sizeof(RTUTF16);
+    for (unsigned i = 0; i <= pDest->string.u16Length; ++i)
         pDest->string.String.ucs2[i] = (uint16_t)pcszSource[i];
 }
 
diff --git a/src/VBox/HostServices/SharedFolders/testcase/tstShflSizes.cpp b/src/VBox/HostServices/SharedFolders/testcase/tstShflSizes.cpp
index 96d27cfa..ce94fdb4 100644
--- a/src/VBox/HostServices/SharedFolders/testcase/tstShflSizes.cpp
+++ b/src/VBox/HostServices/SharedFolders/testcase/tstShflSizes.cpp
@@ -4,7 +4,7 @@
  */
 
 /*
- * Copyright (C) 2006-2007 Oracle Corporation
+ * Copyright (C) 2006-2010 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
  * available from http://www.virtualbox.org. This file is free software;
diff --git a/src/VBox/HostServices/SharedFolders/teststubs.h b/src/VBox/HostServices/SharedFolders/teststubs.h
index 3be52fcc..54c9ef4a 100644
--- a/src/VBox/HostServices/SharedFolders/teststubs.h
+++ b/src/VBox/HostServices/SharedFolders/teststubs.h
@@ -3,7 +3,7 @@
  */
 
 /*
- * Copyright (C) 2011 Oracle Corporation
+ * Copyright (C) 2011-2012 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
  * available from http://www.virtualbox.org. This file is free software;
diff --git a/src/VBox/HostServices/SharedFolders/vbsf.cpp b/src/VBox/HostServices/SharedFolders/vbsf.cpp
index 617239b8..935e94ce 100644
--- a/src/VBox/HostServices/SharedFolders/vbsf.cpp
+++ b/src/VBox/HostServices/SharedFolders/vbsf.cpp
@@ -4,7 +4,7 @@
  */
 
 /*
- * Copyright (C) 2006-2011 Oracle Corporation
+ * Copyright (C) 2006-2013 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
  * available from http://www.virtualbox.org. This file is free software;
@@ -183,15 +183,24 @@ end:
 }
 
 /**
- * Do a simple path check given by pUtf8Path. Verify that the path is within
- * the root directory of the mapping. Count '..' and other path components
- * and check that we do not go over the root.
+ * Check the given UTF-8 path for root escapes.
+ *
+ * Verify that the path is within the root directory of the mapping.  Count '..'
+ * and other path components and check that we do not go over the root.
+ *
+ * @returns VBox status code.
+ * @retval  VINF_SUCCESS
+ * @retval  VERR_INVALID_NAME
+ *
+ * @param   pUtf8Path   The path to check.
+ * @param   cchPath     The length of the path in chars (not code points, but
+ *                      the C type) excluding the string terminator.
  *
  * @remarks This function assumes that the path will be appended to the root
- * directory of the shared folder mapping. Keep that in mind when checking
- * absolute pathes!
+ *          directory of the shared folder mapping.  Keep that in mind when
+ *          checking absolute paths!
  */
-static int vbsfPathCheck(const char *pUtf8Path, size_t cbPath)
+static int vbsfPathCheck(const char *pUtf8Path, size_t cchPath)
 {
     int rc = VINF_SUCCESS;
 
@@ -202,42 +211,42 @@ static int vbsfPathCheck(const char *pUtf8Path, size_t cbPath)
     for (;;)
     {
         /* Skip leading path delimiters. */
-        while (   i < cbPath
+        while (   i < cchPath
                && (pUtf8Path[i] == '\\' || pUtf8Path[i] == '/'))
             i++;
 
-        if (i >= cbPath)
+        if (i >= cchPath)
             break;
 
         /* Check if that is a dot component. */
         int cDots = 0;
-        while (i < cbPath && pUtf8Path[i] == '.')
+        while (i < cchPath && pUtf8Path[i] == '.')
         {
             cDots++;
             i++;
         }
 
         if (   cDots >= 2 /* Consider all multidots sequences as a 'parent dir'. */
-            && (i >= cbPath || (pUtf8Path[i] == '\\' || pUtf8Path[i] == '/')))
+            && (i >= cchPath || (pUtf8Path[i] == '\\' || pUtf8Path[i] == '/')))
         {
             cParentDirs++;
         }
         else if (   cDots == 1
-                 && (i >= cbPath || (pUtf8Path[i] == '\\' || pUtf8Path[i] == '/')))
+                 && (i >= cchPath || (pUtf8Path[i] == '\\' || pUtf8Path[i] == '/')))
         {
             /* Single dot, nothing changes. */
         }
         else
         {
             /* Skip this component. */
-            while (   i < cbPath
+            while (   i < cchPath
                    && (pUtf8Path[i] != '\\' && pUtf8Path[i] != '/'))
                 i++;
 
             cComponents++;
         }
 
-        Assert(i >= cbPath || (pUtf8Path[i] == '\\' || pUtf8Path[i] == '/'));
+        Assert(i >= cchPath || (pUtf8Path[i] == '\\' || pUtf8Path[i] == '/'));
 
         /* Verify counters for every component. */
         if (cParentDirs > cComponents)
@@ -283,6 +292,7 @@ static int vbsfBuildFullPath(SHFLCLIENTDATA *pClient, SHFLROOT root, PSHFLSTRING
             }
             else
             {
+                /** @todo r-bird: Pardon me for asking, but who validates the UTF-8 encoding?*/
                 memcpy(utf8FullPath, pszRoot, cbRoot);
                 utf8FullPath[cbRoot] = '/';
                 memcpy(utf8FullPath + cbRoot + 1, &pPath->String.utf8[0], pPath->u16Length);
@@ -295,7 +305,7 @@ static int vbsfBuildFullPath(SHFLCLIENTDATA *pClient, SHFLROOT root, PSHFLSTRING
         }
         else
         {
-            Log(("vbsfBuildFullPath: RTUtf16ToUtf8 failed with %Rrc\n", rc));
+            Log(("vbsfBuildFullPath: vbsfPathCheck failed with %Rrc\n", rc));
         }
     }
     else
@@ -368,6 +378,7 @@ static int vbsfBuildFullPath(SHFLCLIENTDATA *pClient, SHFLROOT root, PSHFLSTRING
             if (pPath->u16Length)
             {
                 /* Convert and copy components. */
+                size_t   cwcSrc  = pPath->u16Length / sizeof(RTUTF16);
                 PRTUTF16 pwszSrc = &pPath->String.ucs2[0];
 
                 /* Correct path delimiters */
@@ -384,9 +395,12 @@ static int vbsfBuildFullPath(SHFLCLIENTDATA *pClient, SHFLROOT root, PSHFLSTRING
                     LogFlow(("Corrected string %ls\n", pwszSrc));
                 }
                 if (*pwszSrc == RTPATH_DELIMITER)
+                {
                     pwszSrc++;  /* we already appended a delimiter to the first part */
+                    cwcSrc--;
+                }
 
-                rc = RTUtf16ToUtf8Ex(pwszSrc, RTSTR_MAX, &pszDst, cb, NULL);
+                rc = RTUtf16ToUtf8Ex(pwszSrc, cwcSrc, &pszDst, cb, &cbDst);
                 if (RT_FAILURE(rc))
                 {
                     AssertFailed();
@@ -396,8 +410,7 @@ static int vbsfBuildFullPath(SHFLCLIENTDATA *pClient, SHFLROOT root, PSHFLSTRING
 #endif
                     return rc;
                 }
-
-                cbDst = (uint32_t)strlen(pszDst);
+                Assert(cbDst == strlen(pszDst));
 
                 /* Verify that the path is under the root directory. */
                 rc = vbsfPathCheck(pszDst, cbDst);
@@ -405,7 +418,6 @@ static int vbsfBuildFullPath(SHFLCLIENTDATA *pClient, SHFLROOT root, PSHFLSTRING
                 {
 #ifdef RT_OS_DARWIN
                     RTMemFree(pPath);
-                    pPath = pPathParameter;
 #endif
                     return rc;
                 }
diff --git a/src/VBox/HostServices/SharedFolders/vbsf.h b/src/VBox/HostServices/SharedFolders/vbsf.h
index 76979681..0151a223 100644
--- a/src/VBox/HostServices/SharedFolders/vbsf.h
+++ b/src/VBox/HostServices/SharedFolders/vbsf.h
@@ -3,7 +3,7 @@
  */
 
 /*
- * Copyright (C) 2006-2007 Oracle Corporation
+ * Copyright (C) 2006-2011 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
  * available from http://www.virtualbox.org. This file is free software;