VBoxFUSE.cpp@ 45221

Last change on this file since 45221 was 44529, checked in by vboxsync, 12 years ago
header (C) fixes
Property svn:eol-style set to `native` Property svn:keywords set to `Author Date Id Revision`
File size: 44.3 KB

Line
1	/* $Id: VBoxFUSE.cpp 44529 2013-02-04 15:54:15Z vboxsync $ */
2	/** @file
3	* VBoxFUSE - Disk Image Flattening FUSE Program.
4	*/
5
6	/*
7	* Copyright (C) 2009-2012 Oracle Corporation
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License (GPL) as published by the Free Software
13	* Foundation, in version 2 as it comes in the "COPYING" file of the
14	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16	*/
17
18
19	/*******************************************************************************
20	* Header Files *
21	*******************************************************************************/
22	#define LOG_GROUP LOG_GROUP_DEFAULT /** @todo log group */
23	#include <iprt/types.h>
24
25	#if defined(RT_OS_DARWIN) \|\| defined(RT_OS_FREEBSD) \|\| defined(RT_OS_LINUX)
26	# include <sys/param.h>
27	# undef PVM /* Blasted old BSD mess still hanging around darwin. */
28	#endif
29	#define FUSE_USE_VERSION 27
30	#include <fuse.h>
31	#include <errno.h>
32	#include <fcntl.h>
33	#ifndef EDOOFUS
34	# ifdef EBADMACHO
35	# define EDOOFUS EBADMACHO
36	# elif defined(EPROTO)
37	# define EDOOFUS EPROTO /* What a boring lot. */
38	//# elif defined(EXYZ)
39	//# define EDOOFUS EXYZ
40	# else
41	# error "Choose an unlikely and (if possible) fun error number for EDOOFUS."
42	# endif
43	#endif
44
45	#include <VBox/vd.h>
46	#include <VBox/log.h>
47	#include <VBox/err.h>
48	#include <iprt/critsect.h>
49	#include <iprt/assert.h>
50	#include <iprt/asm.h>
51	#include <iprt/mem.h>
52	#include <iprt/string.h>
53	#include <iprt/initterm.h>
54	#include <iprt/stream.h>
55
56
57	/*******************************************************************************
58	* Structures and Typedefs *
59	*******************************************************************************/
60	/**
61	* Node type.
62	*/
63	typedef enum VBOXFUSETYPE
64	{
65	VBOXFUSETYPE_INVALID = 0,
66	VBOXFUSETYPE_DIRECTORY,
67	VBOXFUSETYPE_FLAT_IMAGE,
68	VBOXFUSETYPE_CONTROL_PIPE
69	} VBOXFUSETYPE;
70
71	/**
72	* Stuff common to both directories and files.
73	*/
74	typedef struct VBOXFUSENODE
75	{
76	/** The directory name. */
77	const char *pszName;
78	/** The name length. */
79	size_t cchName;
80	/** The node type. */
81	VBOXFUSETYPE enmType;
82	/** The number of references.
83	* The directory linking this node will always retain one. */
84	int32_t volatile cRefs;
85	/** Critical section serializing access to the node data. */
86	RTCRITSECT CritSect;
87	/** Pointer to the directory (parent). */
88	struct VBOXFUSEDIR *pDir;
89	/** The mode mask. */
90	RTFMODE fMode;
91	/** The User ID of the directory owner. */
92	RTUID Uid;
93	/** The Group ID of the directory. */
94	RTUID Gid;
95	/** The link count. */
96	uint32_t cLinks;
97	/** The inode number. */
98	RTINODE Ino;
99	/** The size of the primary stream. */
100	RTFOFF cbPrimary;
101	} VBOXFUSENODE;
102	typedef VBOXFUSENODE *PVBOXFUSENODE;
103
104	/**
105	* A flat image file.
106	*/
107	typedef struct VBOXFUSEFLATIMAGE
108	{
109	/** The standard bits. */
110	VBOXFUSENODE Node;
111	/** The virtual disk container. */
112	PVBOXHDD pDisk;
113	/** The format name. */
114	char *pszFormat;
115	/** The number of readers.
116	* Read only images will have this set to INT32_MAX/2 on creation. */
117	int32_t cReaders;
118	/** The number of writers. (Just 1 or 0 really.) */
119	int32_t cWriters;
120	} VBOXFUSEFLATIMAGE;
121	typedef VBOXFUSEFLATIMAGE *PVBOXFUSEFLATIMAGE;
122
123	/**
124	* A control pipe (file).
125	*/
126	typedef struct VBOXFUSECTRLPIPE
127	{
128	/** The standard bits. */
129	VBOXFUSENODE Node;
130	} VBOXFUSECTRLPIPE;
131	typedef VBOXFUSECTRLPIPE *PVBOXFUSECTRLPIPE;
132
133
134	/**
135	* A Directory.
136	*
137	* This is just a container of files and subdirectories, nothing special.
138	*/
139	typedef struct VBOXFUSEDIR
140	{
141	/** The standard bits. */
142	VBOXFUSENODE Node;
143	/** The number of directory entries. */
144	uint32_t cEntries;
145	/** Array of pointers to directory entries.
146	* Whether what's being pointed to is a file, directory or something else can be
147	* determined by the enmType field. */
148	PVBOXFUSENODE *paEntries;
149	} VBOXFUSEDIR;
150	typedef VBOXFUSEDIR *PVBOXFUSEDIR;
151
152	/** The number of elements to grow VBOXFUSEDIR::paEntries by. */
153	#define VBOXFUSE_DIR_GROW_BY 2 /* 32 */
154
155
156	/*******************************************************************************
157	* Global Variables *
158	*******************************************************************************/
159	/** The root of the file hierarchy. */
160	static VBOXFUSEDIR *g_pTreeRoot;
161	/** The next inode number. */
162	static RTINODE volatile g_NextIno = 1;
163
164
165	/*******************************************************************************
166	* Internal Functions *
167	*******************************************************************************/
168	static int vboxfuseTreeLookupParent(const char pszPath, const char ppszName, PVBOXFUSEDIR ppDir);
169	static int vboxfuseTreeLookupParentForInsert(const char pszPath, const char ppszName, PVBOXFUSEDIR ppDir);
170
171
172	/**
173	* Node destructor.
174	*
175	* @returns true.
176	* @param pNode The node.
177	* @param fLocked Whether it's locked.
178	*/
179	static bool vboxfuseNodeDestroy(PVBOXFUSENODE pNode, bool fLocked)
180	{
181	Assert(pNode->cRefs == 0);
182
183	/*
184	* Type specific cleanups.
185	*/
186	switch (pNode->enmType)
187	{
188	case VBOXFUSETYPE_DIRECTORY:
189	{
190	PVBOXFUSEDIR pDir = (PVBOXFUSEDIR)pNode;
191	RTMemFree(pDir->paEntries);
192	pDir->paEntries = NULL;
193	pDir->cEntries = 0;
194	break;
195	}
196
197	case VBOXFUSETYPE_FLAT_IMAGE:
198	{
199	PVBOXFUSEFLATIMAGE pFlatImage = (PVBOXFUSEFLATIMAGE)pNode;
200	if (pFlatImage->pDisk)
201	{
202	int rc2 = VDClose(pFlatImage->pDisk, false /* fDelete */); AssertRC(rc2);
203	pFlatImage->pDisk = NULL;
204	}
205	RTStrFree(pFlatImage->pszFormat);
206	pFlatImage->pszFormat = NULL;
207	break;
208	}
209
210	case VBOXFUSETYPE_CONTROL_PIPE:
211	break;
212
213	default:
214	AssertMsgFailed(("%d\n", pNode->enmType));
215	break;
216	}
217
218	/*
219	* Generic cleanup.
220	*/
221	pNode->enmType = VBOXFUSETYPE_INVALID;
222	pNode->pszName = NULL;
223
224	/*
225	* Unlock and destroy the lock, before we finally frees the node.
226	*/
227	if (fLocked)
228	RTCritSectLeave(&pNode->CritSect);
229	RTCritSectDelete(&pNode->CritSect);
230
231	RTMemFree(pNode);
232
233	return true;
234	}
235
236
237	/**
238	* Locks a FUSE node.
239	*
240	* @param pNode The node.
241	*/
242	static void vboxfuseNodeLock(PVBOXFUSENODE pNode)
243	{
244	int rc = RTCritSectEnter(&pNode->CritSect);
245	AssertRC(rc);
246	}
247
248
249	/**
250	* Unlocks a FUSE node.
251	*
252	* @param pNode The node.
253	*/
254	static void vboxfuseNodeUnlock(PVBOXFUSENODE pNode)
255	{
256	int rc = RTCritSectLeave(&pNode->CritSect);
257	AssertRC(rc);
258	}
259
260
261	/**
262	* Retain a VBoxFUSE node.
263	*
264	* @param pNode The node.
265	*/
266	static void vboxfuseNodeRetain(PVBOXFUSENODE pNode)
267	{
268	int32_t cNewRefs = ASMAtomicIncS32(&pNode->cRefs);
269	Assert(cNewRefs != 1);
270	}
271
272
273	/**
274	* Releases a VBoxFUSE node reference.
275	*
276	* @returns true if deleted, false if not.
277	* @param pNode The node.
278	*/
279	static bool vboxfuseNodeRelease(PVBOXFUSENODE pNode)
280	{
281	if (ASMAtomicDecS32(&pNode->cRefs) == 0)
282	return vboxfuseNodeDestroy(pNode, false /* fLocked */);
283	return false;
284	}
285
286
287	/**
288	* Locks and retains a VBoxFUSE node.
289	*
290	* @param pNode The node.
291	*/
292	static void vboxfuseNodeLockAndRetain(PVBOXFUSENODE pNode)
293	{
294	vboxfuseNodeLock(pNode);
295	vboxfuseNodeRetain(pNode);
296	}
297
298
299	/**
300	* Releases a VBoxFUSE node reference and unlocks it.
301	*
302	* @returns true if deleted, false if not.
303	* @param pNode The node.
304	*/
305	static bool vboxfuseNodeReleaseAndUnlock(PVBOXFUSENODE pNode)
306	{
307	if (ASMAtomicDecS32(&pNode->cRefs) == 0)
308	return vboxfuseNodeDestroy(pNode, true /* fLocked */);
309	vboxfuseNodeUnlock(pNode);
310	return false;
311	}
312
313
314	/**
315	* Creates stat info for a locked node.
316	*
317	* @param pNode The node (locked).
318	*/
319	static void vboxfuseNodeFillStat(PVBOXFUSENODE pNode, struct stat *pStat)
320	{
321	pStat->st_dev = 0; /* ignored */
322	pStat->st_ino = pNode->Ino; /* maybe ignored */
323	pStat->st_mode = pNode->fMode;
324	pStat->st_nlink = pNode->cLinks;
325	pStat->st_uid = pNode->Uid;
326	pStat->st_gid = pNode->Gid;
327	pStat->st_rdev = 0;
328	/** @todo file times */
329	pStat->st_atime = 0;
330	// pStat->st_atimensec = 0;
331	pStat->st_mtime = 0;
332	// pStat->st_mtimensec = 0;
333	pStat->st_ctime = 0;
334	// pStat->st_ctimensec = 0;
335	pStat->st_size = pNode->cbPrimary;
336	pStat->st_blocks = (pNode->cbPrimary + DEV_BSIZE - 1) / DEV_BSIZE;
337	pStat->st_blksize = 0x1000; /* ignored */
338	#ifndef RT_OS_LINUX
339	pStat->st_flags = 0;
340	pStat->st_gen = 0;
341	#endif
342	}
343
344
345	/**
346	* Allocates a new node and initialize the node part of it.
347	*
348	* The returned node has one reference.
349	*
350	* @returns VBox status code.
351	*
352	* @param cbNode The size of the node.
353	* @param pszName The name of the node.
354	* @param enmType The node type.
355	* @param pDir The directory (parent).
356	* @param ppNode Where to return the pointer to the node.
357	*/
358	static int vboxfuseNodeAlloc(size_t cbNode, const char *pszName, VBOXFUSETYPE enmType, PVBOXFUSEDIR pDir,
359	PVBOXFUSENODE *ppNode)
360	{
361	Assert(cbNode >= sizeof(VBOXFUSENODE));
362
363	/*
364	* Allocate the memory for it and init the critical section.
365	*/
366	size_t cchName = strlen(pszName);
367	PVBOXFUSENODE pNode = (PVBOXFUSENODE)RTMemAlloc(cchName + 1 + RT_ALIGN_Z(cbNode, 8));
368	if (!pNode)
369	return VERR_NO_MEMORY;
370
371	int rc = RTCritSectInit(&pNode->CritSect);
372	if (RT_FAILURE(rc))
373	{
374	RTMemFree(pNode);
375	return rc;
376	}
377
378	/*
379	* Initialize the members.
380	*/
381	pNode->pszName = (char )memcpy((uint8_t )pNode + RT_ALIGN_Z(cbNode, 8), pszName, cchName + 1);
382	pNode->cchName = cchName;
383	pNode->enmType = enmType;
384	pNode->cRefs = 1;
385	pNode->pDir = pDir;
386	#if 0
387	pNode->fMode = enmType == VBOXFUSETYPE_DIRECTORY ? S_IFDIR \| 0755 : S_IFREG \| 0644;
388	#else
389	pNode->fMode = enmType == VBOXFUSETYPE_DIRECTORY ? S_IFDIR \| 0777 : S_IFREG \| 0666;
390	#endif
391	pNode->Uid = 0;
392	pNode->Gid = 0;
393	pNode->cLinks = 0;
394	pNode->Ino = g_NextIno++; /** @todo make this safe! */
395	pNode->cbPrimary = 0;
396
397	*ppNode = pNode;
398	return VINF_SUCCESS;
399	}
400
401
402	/**
403	* Inserts a node into a directory
404	*
405	* The caller has locked and referenced the directory as well as checked that
406	* the name doesn't already exist within it. On success both the reference and
407	* and link counters will be incremented.
408	*
409	* @returns VBox status code.
410	*
411	* @param pDir The parent directory. Can be NULL when creating the root
412	* directory.
413	* @param pNode The node to insert.
414	*/
415	static int vboxfuseDirInsertChild(PVBOXFUSEDIR pDir, PVBOXFUSENODE pNode)
416	{
417	if (!pDir)
418	{
419	/*
420	* Special case: Root Directory.
421	*/
422	AssertReturn(!g_pTreeRoot, VERR_ALREADY_EXISTS);
423	AssertReturn(pNode->enmType == VBOXFUSETYPE_DIRECTORY, VERR_INTERNAL_ERROR);
424	g_pTreeRoot = (PVBOXFUSEDIR)pNode;
425	}
426	else
427	{
428	/*
429	* Common case.
430	*/
431	if (!(pDir->cEntries % VBOXFUSE_DIR_GROW_BY))
432	{
433	void pvNew = RTMemRealloc(pDir->paEntries, sizeof(pDir->paEntries) * (pDir->cEntries + VBOXFUSE_DIR_GROW_BY));
434	if (!pvNew)
435	return VERR_NO_MEMORY;
436	pDir->paEntries = (PVBOXFUSENODE *)pvNew;
437	}
438	pDir->paEntries[pDir->cEntries++] = pNode;
439	pDir->Node.cLinks++;
440	}
441
442	vboxfuseNodeRetain(pNode);
443	pNode->cLinks++;
444	return VINF_SUCCESS;
445	}
446
447
448	/**
449	* Create a directory node.
450	*
451	* @returns VBox status code.
452	* @param pszPath The path to the directory.
453	* @param ppDir Optional, where to return the new directory locked and
454	* referenced (making cRefs == 2).
455	*/
456	static int vboxfuseDirCreate(const char pszPath, PVBOXFUSEDIR ppDir)
457	{
458	/*
459	* Figure out where the directory is going.
460	*/
461	const char *pszName;
462	PVBOXFUSEDIR pParent;
463	int rc = vboxfuseTreeLookupParentForInsert(pszPath, &pszName, &pParent);
464	if (RT_FAILURE(rc))
465	return rc;
466
467	/*
468	* Allocate and initialize the new directory node.
469	*/
470	PVBOXFUSEDIR pNewDir;
471	rc = vboxfuseNodeAlloc(sizeof(pNewDir), pszName, VBOXFUSETYPE_DIRECTORY, pParent, (PVBOXFUSENODE )&pNewDir);
472	if (RT_SUCCESS(rc))
473	{
474	pNewDir->cEntries = 0;
475	pNewDir->paEntries = NULL;
476
477	/*
478	* Insert it.
479	*/
480	rc = vboxfuseDirInsertChild(pParent, &pNewDir->Node);
481	if ( RT_SUCCESS(rc)
482	&& ppDir)
483	{
484	vboxfuseNodeLockAndRetain(&pNewDir->Node);
485	*ppDir = pNewDir;
486	}
487	vboxfuseNodeRelease(&pNewDir->Node);
488	}
489	if (pParent)
490	vboxfuseNodeReleaseAndUnlock(&pParent->Node);
491	return rc;
492	}
493
494
495	/**
496	* Creates a flattened image
497	*
498	* @returns VBox status code.
499	* @param pszPath Where to create the flattened file in the FUSE file
500	* system.
501	* @param pszImage The image to flatten.
502	* @param ppFile Where to return the pointer to the instance.
503	* Optional.
504	*/
505	static int vboxfuseFlatImageCreate(const char pszPath, const char pszImage, PVBOXFUSEFLATIMAGE *ppFile)
506	{
507	/*
508	* Check that we can create this file.
509	*/
510	const char *pszName;
511	PVBOXFUSEDIR pParent;
512	int rc = vboxfuseTreeLookupParentForInsert(pszPath, &pszName, &pParent);
513	if (RT_FAILURE(rc))
514	return rc;
515	if (pParent)
516	vboxfuseNodeReleaseAndUnlock(&pParent->Node);
517
518	/*
519	* Try open the image file (without holding any locks).
520	*/
521	char *pszFormat;
522	VDTYPE enmType;
523	rc = VDGetFormat(NULL /* pVDIIfsDisk /, NULL / pVDIIfsImage*/, pszImage, &pszFormat, &enmType);
524	if (RT_FAILURE(rc))
525	{
526	LogRel(("VDGetFormat(%s,) failed, rc=%Rrc\n", pszImage, rc));
527	return rc;
528	}
529
530	PVBOXHDD pDisk = NULL;
531	rc = VDCreate(NULL /* pVDIIfsDisk */, enmType, &pDisk);
532	if (RT_SUCCESS(rc))
533	{
534	rc = VDOpen(pDisk, pszFormat, pszImage, 0, NULL /* pVDIfsImage */);
535	if (RT_FAILURE(rc))
536	{
537	LogRel(("VDCreate(,%s,%s,,,) failed, rc=%Rrc\n", pszFormat, pszImage, rc));
538	VDClose(pDisk, false /* fDeletes */);
539	}
540	}
541	else
542	Log(("VDCreate failed, rc=%Rrc\n", rc));
543	if (RT_FAILURE(rc))
544	{
545	RTStrFree(pszFormat);
546	return rc;
547	}
548
549	/*
550	* Allocate and initialize the new directory node.
551	*/
552	rc = vboxfuseTreeLookupParentForInsert(pszPath, &pszName, &pParent);
553	if (RT_SUCCESS(rc))
554	{
555	PVBOXFUSEFLATIMAGE pNewFlatImage;
556	rc = vboxfuseNodeAlloc(sizeof(pNewFlatImage), pszName, VBOXFUSETYPE_FLAT_IMAGE, pParent, (PVBOXFUSENODE )&pNewFlatImage);
557	if (RT_SUCCESS(rc))
558	{
559	pNewFlatImage->pDisk = pDisk;
560	pNewFlatImage->pszFormat = pszFormat;
561	pNewFlatImage->cReaders = VDIsReadOnly(pNewFlatImage->pDisk) ? INT32_MAX / 2 : 0;
562	pNewFlatImage->cWriters = 0;
563	pNewFlatImage->Node.cbPrimary = VDGetSize(pNewFlatImage->pDisk, 0 /* base */);
564
565	/*
566	* Insert it.
567	*/
568	rc = vboxfuseDirInsertChild(pParent, &pNewFlatImage->Node);
569	if ( RT_SUCCESS(rc)
570	&& ppFile)
571	{
572	vboxfuseNodeLockAndRetain(&pNewFlatImage->Node);
573	*ppFile = pNewFlatImage;
574	}
575	vboxfuseNodeRelease(&pNewFlatImage->Node);
576	pDisk = NULL;
577	}
578	if (pParent)
579	vboxfuseNodeReleaseAndUnlock(&pParent->Node);
580	}
581	if (RT_FAILURE(rc) && pDisk != NULL)
582	VDClose(pDisk, false /* fDelete */);
583	return rc;
584	}
585
586
587	//static int vboxfuseTreeMkCtrlPipe(const char pszPath, PVBOXFUSECTRLPIPE ppPipe)
588	//{
589	//}
590
591
592	/**
593	* Looks up a file in the tree.
594	*
595	* Upon successful return the returned node is both referenced and locked. The
596	* call will have to release and unlock it.
597	*
598	* @returns VBox status code
599	* @param pszPath The path to the file.
600	* @param ppNode Where to return the node.
601	*/
602	static int vboxfuseTreeLookup(const char pszPath, PVBOXFUSENODE ppNode)
603	{
604	/*
605	* Root first.
606	*/
607	const char *psz = pszPath;
608	if (*psz != '/')
609	return VERR_FILE_NOT_FOUND;
610
611	PVBOXFUSEDIR pDir = g_pTreeRoot;
612	vboxfuseNodeLockAndRetain(&pDir->Node);
613
614	do psz++;
615	while (*psz == '/');
616	if (!*psz)
617	{
618	/* looking for the root. */
619	*ppNode = &pDir->Node;
620	return VINF_SUCCESS;
621	}
622
623	/*
624	* Take it bit by bit from here on.
625	*/
626	for (;;)
627	{
628	/*
629	* Find the length of the current directory entry and check if it must be file.
630	*/
631	const char * const pszName = psz;
632	psz = strchr(psz, '/');
633	if (!psz)
634	psz = strchr(pszName, '\0');
635	size_t cchName = psz - pszName;
636
637	bool fMustBeDir = *psz == '/';
638	while (*psz == '/')
639	psz++;
640
641	/*
642	* Look it up.
643	* This is safe as the directory will hold a reference to each node
644	* so the nodes cannot possibly be destroyed while we're searching them.
645	*/
646	PVBOXFUSENODE pNode = NULL;
647	uint32_t i = pDir->cEntries;
648	PVBOXFUSENODE *paEntries = pDir->paEntries;
649	while (i-- > 0)
650	{
651	PVBOXFUSENODE pCur = paEntries[i];
652	if ( pCur->cchName == cchName
653	&& !memcmp(pCur->pszName, pszName, cchName))
654	{
655	pNode = pCur;
656	vboxfuseNodeLockAndRetain(pNode);
657	break;
658	}
659	}
660	vboxfuseNodeReleaseAndUnlock(&pDir->Node);
661
662	if (!pNode)
663	return *psz ? VERR_PATH_NOT_FOUND : VERR_FILE_NOT_FOUND;
664	if ( fMustBeDir
665	&& pNode->enmType != VBOXFUSETYPE_DIRECTORY)
666	{
667	vboxfuseNodeReleaseAndUnlock(pNode);
668	return VERR_NOT_A_DIRECTORY;
669	}
670
671	/*
672	* Are we done?
673	*/
674	if (!*psz)
675	{
676	*ppNode = pNode;
677	return VINF_SUCCESS;
678	}
679
680	/* advance */
681	pDir = (PVBOXFUSEDIR)pNode;
682	}
683	}
684
685
686	/**
687	* Errno conversion wrapper around vboxfuseTreeLookup().
688	*
689	* @returns 0 on success, negated errno on failure.
690	* @param pszPath The path to the file.
691	* @param ppNode Where to return the node.
692	*/
693	static int vboxfuseTreeLookupErrno(const char pszPath, PVBOXFUSENODE ppNode)
694	{
695	int rc = vboxfuseTreeLookup(pszPath, ppNode);
696	if (RT_SUCCESS(rc))
697	return 0;
698	return -RTErrConvertToErrno(rc);
699	}
700
701
702	/**
703	* Looks up a parent directory in the tree.
704	*
705	* Upon successful return the returned directory is both referenced and locked.
706	* The call will have to release and unlock it.
707	*
708	* @returns VBox status code.
709	*
710	* @param pszPath The path to the file which parent we seek.
711	* @param ppszName Where to return the pointer to the child's name within
712	* pszPath.
713	* @param ppDir Where to return the parent directory.
714	*/
715	static int vboxfuseTreeLookupParent(const char pszPath, const char ppszName, PVBOXFUSEDIR ppDir)
716	{
717	/*
718	* Root first.
719	*/
720	const char *psz = pszPath;
721	if (*psz != '/')
722	return VERR_INVALID_PARAMETER;
723	do psz++;
724	while (*psz == '/');
725	if (!*psz)
726	{
727	/* looking for the root. */
728	*ppszName = psz + 1;
729	*ppDir = NULL;
730	return VINF_SUCCESS;
731	}
732
733	/*
734	* Take it bit by bit from here on.
735	*/
736	PVBOXFUSEDIR pDir = g_pTreeRoot;
737	AssertReturn(pDir, VERR_WRONG_ORDER);
738	vboxfuseNodeLockAndRetain(&pDir->Node);
739	for (;;)
740	{
741	/*
742	* Find the length of the current directory entry and check if it must be file.
743	*/
744	const char * const pszName = psz;
745	psz = strchr(psz, '/');
746	if (!psz)
747	{
748	/* that's all folks.*/
749	*ppszName = pszName;
750	*ppDir = pDir;
751	return VINF_SUCCESS;
752	}
753	size_t cchName = psz - pszName;
754
755	bool fMustBeDir = *psz == '/';
756	while (*psz == '/')
757	psz++;
758
759	/* Trailing slashes are not allowed (because it's simpler without them). */
760	if (!*psz)
761	return VERR_INVALID_PARAMETER;
762
763	/*
764	* Look it up.
765	* This is safe as the directory will hold a reference to each node
766	* so the nodes cannot possibly be destroyed while we're searching them.
767	*/
768	PVBOXFUSENODE pNode = NULL;
769	uint32_t i = pDir->cEntries;
770	PVBOXFUSENODE *paEntries = pDir->paEntries;
771	while (i-- > 0)
772	{
773	PVBOXFUSENODE pCur = paEntries[i];
774	if ( pCur->cchName == cchName
775	&& !memcmp(pCur->pszName, pszName, cchName))
776	{
777	pNode = pCur;
778	vboxfuseNodeLockAndRetain(pNode);
779	break;
780	}
781	}
782	vboxfuseNodeReleaseAndUnlock(&pDir->Node);
783
784	if (!pNode)
785	return VERR_FILE_NOT_FOUND;
786	if ( fMustBeDir
787	&& pNode->enmType != VBOXFUSETYPE_DIRECTORY)
788	{
789	vboxfuseNodeReleaseAndUnlock(pNode);
790	return VERR_PATH_NOT_FOUND;
791	}
792
793	/* advance */
794	pDir = (PVBOXFUSEDIR)pNode;
795	}
796	}
797
798
799	/**
800	* Looks up a parent directory in the tree and checking that the specified child
801	* doesn't already exist.
802	*
803	* Upon successful return the returned directory is both referenced and locked.
804	* The call will have to release and unlock it.
805	*
806	* @returns VBox status code.
807	*
808	* @param pszPath The path to the file which parent we seek.
809	* @param ppszName Where to return the pointer to the child's name within
810	* pszPath.
811	* @param ppDir Where to return the parent directory.
812	*/
813	static int vboxfuseTreeLookupParentForInsert(const char pszPath, const char ppszName, PVBOXFUSEDIR ppDir)
814	{
815	/*
816	* Lookup the parent directory using vboxfuseTreeLookupParent first.
817	*/
818	const char *pszName;
819	PVBOXFUSEDIR pDir;
820	int rc = vboxfuseTreeLookupParent(pszPath, &pszName, &pDir);
821	if (RT_SUCCESS(rc))
822	{
823	/*
824	* Check that it doesn't exist already
825	*/
826	if (pDir)
827	{
828	size_t const cchName = strlen(pszName);
829	uint32_t i = pDir->cEntries;
830	PVBOXFUSENODE *paEntries = pDir->paEntries;
831	while (i-- > 0)
832	{
833	PVBOXFUSENODE pCur = paEntries[i];
834	if ( pCur->cchName == cchName
835	&& !memcmp(pCur->pszName, pszName, cchName))
836	{
837	vboxfuseNodeReleaseAndUnlock(&pDir->Node);
838	rc = VERR_ALREADY_EXISTS;
839	break;
840	}
841	}
842	}
843	if (RT_SUCCESS(rc))
844	{
845	*ppDir = pDir;
846	*ppszName = pszName;
847	}
848	}
849	return rc;
850	}
851
852
853
854
855
856	/** @copydoc fuse_operations::getattr */
857	static int vboxfuseOp_getattr(const char pszPath, struct stat pStat)
858	{
859	PVBOXFUSENODE pNode;
860	int rc = vboxfuseTreeLookupErrno(pszPath, &pNode);
861	if (!rc)
862	{
863	vboxfuseNodeFillStat(pNode, pStat);
864	vboxfuseNodeReleaseAndUnlock(pNode);
865	}
866	LogFlow(("vboxfuseOp_getattr: rc=%d \"%s\"\n", rc, pszPath));
867	return rc;
868	}
869
870
871	/** @copydoc fuse_operations::opendir */
872	static int vboxfuseOp_opendir(const char pszPath, struct fuse_file_info pInfo)
873	{
874	PVBOXFUSENODE pNode;
875	int rc = vboxfuseTreeLookupErrno(pszPath, &pNode);
876	if (!rc)
877	{
878	/*
879	* Check that it's a directory and that the caller should see it.
880	*/
881	if (pNode->enmType != VBOXFUSETYPE_DIRECTORY)
882	rc = -ENOTDIR;
883	/** @todo access checks. */
884	else
885	{
886	/** @todo update the accessed TS? */
887
888	/*
889	* Put a reference to the node in the fuse_file_info::fh member so
890	* we don't have to parse the path in readdir.
891	*/
892	pInfo->fh = (uintptr_t)pNode;
893	vboxfuseNodeUnlock(pNode);
894	}
895
896	/* cleanup */
897	if (rc)
898	vboxfuseNodeReleaseAndUnlock(pNode);
899	}
900	LogFlow(("vboxfuseOp_opendir: rc=%d \"%s\"\n", rc, pszPath));
901	return rc;
902	}
903
904
905	/** @copydoc fuse_operations::readdir */
906	static int vboxfuseOp_readdir(const char pszPath, void pvBuf, fuse_fill_dir_t pfnFiller,
907	off_t offDir, struct fuse_file_info *pInfo)
908	{
909	PVBOXFUSEDIR pDir = (PVBOXFUSEDIR)(uintptr_t)pInfo->fh;
910	AssertPtr(pDir);
911	Assert(pDir->Node.enmType == VBOXFUSETYPE_DIRECTORY);
912	vboxfuseNodeLock(&pDir->Node);
913	LogFlow(("vboxfuseOp_readdir: offDir=%llx \"%s\"\n", (uint64_t)offDir, pszPath));
914
915	#define VBOXFUSE_FAKE_DIRENT_SIZE 512
916
917	/*
918	* First the mandatory dot and dot-dot entries.
919	*/
920	struct stat st;
921	int rc = 0;
922	if (!offDir)
923	{
924	offDir += VBOXFUSE_FAKE_DIRENT_SIZE;
925	vboxfuseNodeFillStat(&pDir->Node, &st);
926	rc = pfnFiller(pvBuf, ".", &st, offDir);
927	}
928	if ( offDir == VBOXFUSE_FAKE_DIRENT_SIZE
929	&& !rc)
930	{
931	offDir += VBOXFUSE_FAKE_DIRENT_SIZE;
932	rc = pfnFiller(pvBuf, "..", NULL, offDir);
933	}
934
935	/*
936	* Convert the offset to a directory index and start/continue filling the buffer.
937	* The entries only needs locking since the directory already has a reference
938	* to each of them.
939	*/
940	Assert(offDir >= VBOXFUSE_FAKE_DIRENT_SIZE * 2 \|\| rc);
941	uint32_t i = offDir / VBOXFUSE_FAKE_DIRENT_SIZE - 2;
942	while ( !rc
943	&& i < pDir->cEntries)
944	{
945	PVBOXFUSENODE pNode = pDir->paEntries[i];
946	vboxfuseNodeLock(pNode);
947
948	vboxfuseNodeFillStat(pNode, &st);
949	offDir = (i + 3) * VBOXFUSE_FAKE_DIRENT_SIZE;
950	rc = pfnFiller(pvBuf, pNode->pszName, &st, offDir);
951
952	vboxfuseNodeUnlock(pNode);
953
954	/* next */
955	i++;
956	}
957
958	vboxfuseNodeUnlock(&pDir->Node);
959	LogFlow(("vboxfuseOp_readdir: returns offDir=%llx\n", (uint64_t)offDir));
960	return 0;
961	}
962
963
964	/** @copydoc fuse_operations::releasedir */
965	static int vboxfuseOp_releasedir(const char pszPath, struct fuse_file_info pInfo)
966	{
967	PVBOXFUSEDIR pDir = (PVBOXFUSEDIR)(uintptr_t)pInfo->fh;
968	AssertPtr(pDir);
969	Assert(pDir->Node.enmType == VBOXFUSETYPE_DIRECTORY);
970	pInfo->fh = 0;
971	vboxfuseNodeRelease(&pDir->Node);
972	LogFlow(("vboxfuseOp_releasedir: \"%s\"\n", pszPath));
973	return 0;
974	}
975
976
977	/** @copydoc fuse_operations::symlink */
978	static int vboxfuseOp_symlink(const char pszDst, const char pszPath)
979	{
980	/*
981	* "Interface" for mounting a image.
982	*/
983	int rc = vboxfuseFlatImageCreate(pszPath, pszDst, NULL);
984	if (RT_SUCCESS(rc))
985	{
986	Log(("vboxfuseOp_symlink: \"%s\" => \"%s\" SUCCESS!\n", pszPath, pszDst));
987	return 0;
988	}
989
990	LogFlow(("vboxfuseOp_symlink: \"%s\" => \"%s\" rc=%Rrc\n", pszPath, pszDst, rc));
991	return -RTErrConvertToErrno(rc);
992	}
993
994
995	/** @copydoc fuse_operations::open */
996	static int vboxfuseOp_open(const char pszPath, struct fuse_file_info pInfo)
997	{
998	LogFlow(("vboxfuseOp_open(\"%s\", .flags=%#x)\n", pszPath, pInfo->flags));
999
1000	/*
1001	* Validate incoming flags.
1002	*/
1003	#ifdef RT_OS_DARWIN
1004	if (pInfo->flags & (O_APPEND \| O_NONBLOCK \| O_SYMLINK \| O_NOCTTY \| O_SHLOCK \| O_EXLOCK \| O_ASYNC
1005	\| O_CREAT \| O_TRUNC \| O_EXCL \| O_EVTONLY))
1006	return -EINVAL;
1007	if ((pInfo->flags & O_ACCMODE) == O_ACCMODE)
1008	return -EINVAL;
1009	#elif defined(RT_OS_LINUX)
1010	if (pInfo->flags & ( O_APPEND \| O_ASYNC \| O_DIRECT /* \| O_LARGEFILE ? */
1011	\| O_NOATIME \| O_NOCTTY \| O_NOFOLLOW \| O_NONBLOCK
1012	/* \| O_SYNC ? */))
1013	return -EINVAL;
1014	if ((pInfo->flags & O_ACCMODE) == O_ACCMODE)
1015	return -EINVAL;
1016	#elif defined(RT_OS_FREEBSD)
1017	if (pInfo->flags & ( O_APPEND \| O_ASYNC \| O_DIRECT /* \| O_LARGEFILE ? */
1018	\| O_NOCTTY \| O_NOFOLLOW \| O_NONBLOCK
1019	/* \| O_SYNC ? */))
1020	return -EINVAL;
1021	if ((pInfo->flags & O_ACCMODE) == O_ACCMODE)
1022	return -EINVAL;
1023	#else
1024	# error "Port me"
1025	#endif
1026
1027	PVBOXFUSENODE pNode;
1028	int rc = vboxfuseTreeLookupErrno(pszPath, &pNode);
1029	if (!rc)
1030	{
1031	/*
1032	* Check flags and stuff.
1033	*/
1034	switch (pNode->enmType)
1035	{
1036	/* not expected here? */
1037	case VBOXFUSETYPE_DIRECTORY:
1038	AssertFailed();
1039	rc = -EISDIR;
1040	break;
1041
1042	case VBOXFUSETYPE_FLAT_IMAGE:
1043	{
1044	PVBOXFUSEFLATIMAGE pFlatImage = (PVBOXFUSEFLATIMAGE)pNode;
1045	#ifdef O_DIRECTORY
1046	if (pInfo->flags & O_DIRECTORY)
1047	rc = -ENOTDIR;
1048	#endif
1049	if ( (pInfo->flags & O_ACCMODE) == O_WRONLY
1050	\|\| (pInfo->flags & O_ACCMODE) == O_RDWR)
1051	{
1052	if ( pFlatImage->cWriters == 0
1053	&& pFlatImage->cReaders == 0)
1054	pFlatImage->cWriters++;
1055	else
1056	rc = -ETXTBSY;
1057	}
1058	else if ((pInfo->flags & O_ACCMODE) == O_RDONLY)
1059	{
1060	if (pFlatImage->cWriters == 0)
1061	{
1062	if (pFlatImage->cReaders + 1 < ( pFlatImage->cReaders < INT32_MAX / 2
1063	? INT32_MAX / 4
1064	: INT32_MAX / 2 + INT32_MAX / 4) )
1065	pFlatImage->cReaders++;
1066	else
1067	rc = -EMLINK;
1068	}
1069	else
1070	rc = -ETXTBSY;
1071	}
1072	break;
1073	}
1074
1075	case VBOXFUSETYPE_CONTROL_PIPE:
1076	rc = -ENOTSUP;
1077	break;
1078
1079	default:
1080	rc = -EDOOFUS;
1081	break;
1082	}
1083	if (!rc)
1084	{
1085	/*
1086	* Put a reference to the node in the fuse_file_info::fh member so
1087	* we don't have to parse the path in the other file methods.
1088	*/
1089	pInfo->fh = (uintptr_t)pNode;
1090	vboxfuseNodeUnlock(pNode);
1091	}
1092	else
1093	{
1094	/* cleanup */
1095	vboxfuseNodeReleaseAndUnlock(pNode);
1096	}
1097	}
1098	LogFlow(("vboxfuseOp_opendir: rc=%d \"%s\"\n", rc, pszPath));
1099	return rc;
1100	}
1101
1102
1103	/** @copydoc fuse_operations::release */
1104	static int vboxfuseOp_release(const char pszPath, struct fuse_file_info pInfo)
1105	{
1106	PVBOXFUSENODE pNode = (PVBOXFUSENODE)(uintptr_t)pInfo->fh;
1107	AssertPtr(pNode);
1108	pInfo->fh = 0;
1109
1110	switch (pNode->enmType)
1111	{
1112	case VBOXFUSETYPE_DIRECTORY:
1113	/* nothing to do */
1114	vboxfuseNodeRelease(pNode);
1115	break;
1116
1117	case VBOXFUSETYPE_FLAT_IMAGE:
1118	{
1119	PVBOXFUSEFLATIMAGE pFlatImage = (PVBOXFUSEFLATIMAGE)pNode;
1120	vboxfuseNodeLock(&pFlatImage->Node);
1121
1122	if ( (pInfo->flags & O_ACCMODE) == O_WRONLY
1123	\|\| (pInfo->flags & O_ACCMODE) == O_RDWR)
1124	{
1125	pFlatImage->cWriters--;
1126	Assert(pFlatImage->cWriters >= 0);
1127	}
1128	else if ((pInfo->flags & O_ACCMODE) == O_RDONLY)
1129	{
1130	pFlatImage->cReaders--;
1131	Assert(pFlatImage->cReaders >= 0);
1132	}
1133	else
1134	AssertFailed();
1135
1136	vboxfuseNodeReleaseAndUnlock(&pFlatImage->Node);
1137	break;
1138	}
1139
1140	case VBOXFUSETYPE_CONTROL_PIPE:
1141	/* nothing to do yet */
1142	vboxfuseNodeRelease(pNode);
1143	break;
1144
1145	default:
1146	AssertMsgFailed(("%s\n", pszPath));
1147	return -EDOOFUS;
1148	}
1149
1150	LogFlow(("vboxfuseOp_release: \"%s\"\n", pszPath));
1151	return 0;
1152	}
1153
1154	/** The VDRead/VDWrite block granularity. */
1155	#define VBOXFUSE_MIN_SIZE 512
1156	/** Offset mask corresponding to VBOXFUSE_MIN_SIZE. */
1157	#define VBOXFUSE_MIN_SIZE_MASK_OFF (0x1ff)
1158	/** Block mask corresponding to VBOXFUSE_MIN_SIZE. */
1159	#define VBOXFUSE_MIN_SIZE_MASK_BLK (~UINT64_C(0x1ff))
1160
1161	/** @copydoc fuse_operations::read */
1162	static int vboxfuseOp_read(const char pszPath, char pbBuf, size_t cbBuf,
1163	off_t offFile, struct fuse_file_info *pInfo)
1164	{
1165	/* paranoia */
1166	AssertReturn((int)cbBuf >= 0, -EINVAL);
1167	AssertReturn((unsigned)cbBuf == cbBuf, -EINVAL);
1168	AssertReturn(offFile >= 0, -EINVAL);
1169	AssertReturn((off_t)(offFile + cbBuf) >= offFile, -EINVAL);
1170
1171	PVBOXFUSENODE pNode = (PVBOXFUSENODE)(uintptr_t)pInfo->fh;
1172	AssertPtr(pNode);
1173	switch (pNode->enmType)
1174	{
1175	case VBOXFUSETYPE_DIRECTORY:
1176	return -ENOTSUP;
1177
1178	case VBOXFUSETYPE_FLAT_IMAGE:
1179	{
1180	PVBOXFUSEFLATIMAGE pFlatImage = (PVBOXFUSEFLATIMAGE)(uintptr_t)pInfo->fh;
1181	LogFlow(("vboxfuseOp_read: offFile=%#llx cbBuf=%#zx pszPath=\"%s\"\n", (uint64_t)offFile, cbBuf, pszPath));
1182	vboxfuseNodeLock(&pFlatImage->Node);
1183
1184	int rc;
1185	if ((off_t)(offFile + cbBuf) < offFile)
1186	rc = -EINVAL;
1187	else if (offFile >= pFlatImage->Node.cbPrimary)
1188	rc = 0;
1189	else if (!cbBuf)
1190	rc = 0;
1191	else
1192	{
1193	/* Adjust for EOF. */
1194	if ((off_t)(offFile + cbBuf) >= pFlatImage->Node.cbPrimary)
1195	cbBuf = pFlatImage->Node.cbPrimary - offFile;
1196
1197	/*
1198	* Aligned read?
1199	*/
1200	int rc2;
1201	if ( !(offFile & VBOXFUSE_MIN_SIZE_MASK_OFF)
1202	&& !(cbBuf & VBOXFUSE_MIN_SIZE_MASK_OFF))
1203	rc2 = VDRead(pFlatImage->pDisk, offFile, pbBuf, cbBuf);
1204	else
1205	{
1206	/*
1207	* Unaligned read - lots of extra work.
1208	*/
1209	uint8_t abBlock[VBOXFUSE_MIN_SIZE];
1210	if (((offFile + cbBuf) & VBOXFUSE_MIN_SIZE_MASK_BLK) == (offFile & VBOXFUSE_MIN_SIZE_MASK_BLK))
1211	{
1212	/* a single partial block. */
1213	rc2 = VDRead(pFlatImage->pDisk, offFile & VBOXFUSE_MIN_SIZE_MASK_BLK, abBlock, VBOXFUSE_MIN_SIZE);
1214	if (RT_SUCCESS(rc2))
1215	memcpy(pbBuf, &abBlock[offFile & VBOXFUSE_MIN_SIZE_MASK_OFF], cbBuf);
1216	}
1217	else
1218	{
1219	/* read unaligned head. */
1220	rc2 = VINF_SUCCESS;
1221	if (offFile & VBOXFUSE_MIN_SIZE_MASK_OFF)
1222	{
1223	rc2 = VDRead(pFlatImage->pDisk, offFile & VBOXFUSE_MIN_SIZE_MASK_BLK, abBlock, VBOXFUSE_MIN_SIZE);
1224	if (RT_SUCCESS(rc2))
1225	{
1226	size_t cbCopy = VBOXFUSE_MIN_SIZE - (offFile & VBOXFUSE_MIN_SIZE_MASK_OFF);
1227	memcpy(pbBuf, &abBlock[offFile & VBOXFUSE_MIN_SIZE_MASK_OFF], cbCopy);
1228	pbBuf += cbCopy;
1229	offFile += cbCopy;
1230	cbBuf -= cbCopy;
1231	}
1232	}
1233
1234	/* read the middle. */
1235	Assert(!(offFile & VBOXFUSE_MIN_SIZE_MASK_OFF));
1236	if (cbBuf >= VBOXFUSE_MIN_SIZE && RT_SUCCESS(rc2))
1237	{
1238	size_t cbRead = cbBuf & VBOXFUSE_MIN_SIZE_MASK_BLK;
1239	rc2 = VDRead(pFlatImage->pDisk, offFile, pbBuf, cbRead);
1240	if (RT_SUCCESS(rc2))
1241	{
1242	pbBuf += cbRead;
1243	offFile += cbRead;
1244	cbBuf -= cbRead;
1245	}
1246	}
1247
1248	/* unaligned tail read. */
1249	Assert(cbBuf < VBOXFUSE_MIN_SIZE);
1250	Assert(!(offFile & VBOXFUSE_MIN_SIZE_MASK_OFF));
1251	if (cbBuf && RT_SUCCESS(rc2))
1252	{
1253	rc2 = VDRead(pFlatImage->pDisk, offFile, abBlock, VBOXFUSE_MIN_SIZE);
1254	if (RT_SUCCESS(rc2))
1255	memcpy(pbBuf, &abBlock[0], cbBuf);
1256	}
1257	}
1258	}
1259
1260	/* convert the return code */
1261	if (RT_SUCCESS(rc2))
1262	rc = cbBuf;
1263	else
1264	rc = -RTErrConvertToErrno(rc2);
1265	}
1266
1267	vboxfuseNodeUnlock(&pFlatImage->Node);
1268	return rc;
1269	}
1270
1271	case VBOXFUSETYPE_CONTROL_PIPE:
1272	return -ENOTSUP;
1273
1274	default:
1275	AssertMsgFailed(("%s\n", pszPath));
1276	return -EDOOFUS;
1277	}
1278	}
1279
1280
1281	/** @copydoc fuse_operations::write */
1282	static int vboxfuseOp_write(const char pszPath, const char pbBuf, size_t cbBuf,
1283	off_t offFile, struct fuse_file_info *pInfo)
1284	{
1285	/* paranoia */
1286	AssertReturn((int)cbBuf >= 0, -EINVAL);
1287	AssertReturn((unsigned)cbBuf == cbBuf, -EINVAL);
1288	AssertReturn(offFile >= 0, -EINVAL);
1289	AssertReturn((off_t)(offFile + cbBuf) >= offFile, -EINVAL);
1290
1291	PVBOXFUSENODE pNode = (PVBOXFUSENODE)(uintptr_t)pInfo->fh;
1292	AssertPtr(pNode);
1293	switch (pNode->enmType)
1294	{
1295	case VBOXFUSETYPE_DIRECTORY:
1296	return -ENOTSUP;
1297
1298	case VBOXFUSETYPE_FLAT_IMAGE:
1299	{
1300	PVBOXFUSEFLATIMAGE pFlatImage = (PVBOXFUSEFLATIMAGE)(uintptr_t)pInfo->fh;
1301	LogFlow(("vboxfuseOp_write: offFile=%#llx cbBuf=%#zx pszPath=\"%s\"\n", (uint64_t)offFile, cbBuf, pszPath));
1302	vboxfuseNodeLock(&pFlatImage->Node);
1303
1304	int rc;
1305	if ((off_t)(offFile + cbBuf) < offFile)
1306	rc = -EINVAL;
1307	else if (offFile >= pFlatImage->Node.cbPrimary)
1308	rc = 0;
1309	else if (!cbBuf)
1310	rc = 0;
1311	else
1312	{
1313	/* Adjust for EOF. */
1314	if ((off_t)(offFile + cbBuf) >= pFlatImage->Node.cbPrimary)
1315	cbBuf = pFlatImage->Node.cbPrimary - offFile;
1316
1317	/*
1318	* Aligned write?
1319	*/
1320	int rc2;
1321	if ( !(offFile & VBOXFUSE_MIN_SIZE_MASK_OFF)
1322	&& !(cbBuf & VBOXFUSE_MIN_SIZE_MASK_OFF))
1323	rc2 = VDWrite(pFlatImage->pDisk, offFile, pbBuf, cbBuf);
1324	else
1325	{
1326	/*
1327	* Unaligned write - lots of extra work.
1328	*/
1329	uint8_t abBlock[VBOXFUSE_MIN_SIZE];
1330	if (((offFile + cbBuf) & VBOXFUSE_MIN_SIZE_MASK_BLK) == (offFile & VBOXFUSE_MIN_SIZE_MASK_BLK))
1331	{
1332	/* a single partial block. */
1333	rc2 = VDRead(pFlatImage->pDisk, offFile & VBOXFUSE_MIN_SIZE_MASK_BLK, abBlock, VBOXFUSE_MIN_SIZE);
1334	if (RT_SUCCESS(rc2))
1335	{
1336	memcpy(&abBlock[offFile & VBOXFUSE_MIN_SIZE_MASK_OFF], pbBuf, cbBuf);
1337	/* Update the block */
1338	rc2 = VDWrite(pFlatImage->pDisk, offFile & VBOXFUSE_MIN_SIZE_MASK_BLK, abBlock, VBOXFUSE_MIN_SIZE);
1339	}
1340	}
1341	else
1342	{
1343	/* read unaligned head. */
1344	rc2 = VINF_SUCCESS;
1345	if (offFile & VBOXFUSE_MIN_SIZE_MASK_OFF)
1346	{
1347	rc2 = VDRead(pFlatImage->pDisk, offFile & VBOXFUSE_MIN_SIZE_MASK_BLK, abBlock, VBOXFUSE_MIN_SIZE);
1348	if (RT_SUCCESS(rc2))
1349	{
1350	size_t cbCopy = VBOXFUSE_MIN_SIZE - (offFile & VBOXFUSE_MIN_SIZE_MASK_OFF);
1351	memcpy(&abBlock[offFile & VBOXFUSE_MIN_SIZE_MASK_OFF], pbBuf, cbCopy);
1352	pbBuf += cbCopy;
1353	offFile += cbCopy;
1354	cbBuf -= cbCopy;
1355	rc2 = VDWrite(pFlatImage->pDisk, offFile & VBOXFUSE_MIN_SIZE_MASK_BLK, abBlock, VBOXFUSE_MIN_SIZE);
1356	}
1357	}
1358
1359	/* write the middle. */
1360	Assert(!(offFile & VBOXFUSE_MIN_SIZE_MASK_OFF));
1361	if (cbBuf >= VBOXFUSE_MIN_SIZE && RT_SUCCESS(rc2))
1362	{
1363	size_t cbWrite = cbBuf & VBOXFUSE_MIN_SIZE_MASK_BLK;
1364	rc2 = VDWrite(pFlatImage->pDisk, offFile, pbBuf, cbWrite);
1365	if (RT_SUCCESS(rc2))
1366	{
1367	pbBuf += cbWrite;
1368	offFile += cbWrite;
1369	cbBuf -= cbWrite;
1370	}
1371	}
1372
1373	/* unaligned tail write. */
1374	Assert(cbBuf < VBOXFUSE_MIN_SIZE);
1375	Assert(!(offFile & VBOXFUSE_MIN_SIZE_MASK_OFF));
1376	if (cbBuf && RT_SUCCESS(rc2))
1377	{
1378	rc2 = VDRead(pFlatImage->pDisk, offFile, abBlock, VBOXFUSE_MIN_SIZE);
1379	if (RT_SUCCESS(rc2))
1380	{
1381	memcpy(&abBlock[0], pbBuf, cbBuf);
1382	rc2 = VDWrite(pFlatImage->pDisk, offFile, abBlock, VBOXFUSE_MIN_SIZE);
1383	}
1384	}
1385	}
1386	}
1387
1388	/* convert the return code */
1389	if (RT_SUCCESS(rc2))
1390	rc = cbBuf;
1391	else
1392	rc = -RTErrConvertToErrno(rc2);
1393	}
1394
1395	vboxfuseNodeUnlock(&pFlatImage->Node);
1396	return rc;
1397	}
1398
1399	case VBOXFUSETYPE_CONTROL_PIPE:
1400	return -ENOTSUP;
1401
1402	default:
1403	AssertMsgFailed(("%s\n", pszPath));
1404	return -EDOOFUS;
1405	}
1406	}
1407
1408
1409	/**
1410	* The FUSE operations.
1411	*
1412	* @remarks We'll initialize this manually since we cannot use C99 style
1413	* initialzer designations in C++ (yet).
1414	*/
1415	static struct fuse_operations g_vboxfuseOps;
1416
1417
1418
1419	int main(int argc, char **argv)
1420	{
1421	/*
1422	* Initialize the runtime and VD.
1423	*/
1424	int rc = RTR3InitExe(argc, &argv, 0);
1425	if (RT_FAILURE(rc))
1426	{
1427	RTStrmPrintf(g_pStdErr, "VBoxFUSE: RTR3InitExe failed, rc=%Rrc\n", rc);
1428	return 1;
1429	}
1430	RTPrintf("VBoxFUSE: Hello...\n");
1431	rc = VDInit();
1432	if (RT_FAILURE(rc))
1433	{
1434	RTStrmPrintf(g_pStdErr, "VBoxFUSE: VDInit failed, rc=%Rrc\n", rc);
1435	return 1;
1436	}
1437
1438	/*
1439	* Initializes the globals and populate the file hierarchy.
1440	*/
1441	rc = vboxfuseDirCreate("/", NULL);
1442	if (RT_SUCCESS(rc))
1443	rc = vboxfuseDirCreate("/FlattenedImages", NULL);
1444	if (RT_FAILURE(rc))
1445	{
1446	RTStrmPrintf(g_pStdErr, "VBoxFUSE: vboxfuseDirCreate failed, rc=%Rrc\n", rc);
1447	return 1;
1448	}
1449
1450	/*
1451	* Initialize the g_vboxfuseOps. (C++ sucks!)
1452	*/
1453	memset(&g_vboxfuseOps, 0, sizeof(g_vboxfuseOps));
1454	g_vboxfuseOps.getattr = vboxfuseOp_getattr;
1455	g_vboxfuseOps.opendir = vboxfuseOp_opendir;
1456	g_vboxfuseOps.readdir = vboxfuseOp_readdir;
1457	g_vboxfuseOps.releasedir = vboxfuseOp_releasedir;
1458	g_vboxfuseOps.symlink = vboxfuseOp_symlink;
1459	g_vboxfuseOps.open = vboxfuseOp_open;
1460	g_vboxfuseOps.read = vboxfuseOp_read;
1461	g_vboxfuseOps.write = vboxfuseOp_write;
1462	g_vboxfuseOps.release = vboxfuseOp_release;
1463
1464	/*
1465	* Hand control over to libfuse.
1466	*/
1467
1468	#if 0
1469	/** @todo multithreaded fun. */
1470	#else
1471	rc = fuse_main(argc, argv, &g_vboxfuseOps, NULL);
1472	#endif
1473	RTPrintf("VBoxFUSE: fuse_main -> %d\n", rc);
1474	return rc;
1475	}
1476

Note: See TracBrowser for help on using the repository browser.

source: vbox/trunk/src/VBox/ImageMounter/VBoxFUSE/VBoxFUSE.cpp@ 45221

Download in other formats: