DrvChar.cpp@ 55747

Last change on this file since 55747 was 45061, checked in by vboxsync, 12 years ago
Review of PDM driver destructors making sure that variables they use are correctly initialized in the constructor. Found several RTFileClose(0) cases.
Property svn:eol-style set to `native` Property svn:keywords set to `Author Date Id Revision`
File size: 14.6 KB

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1	/* $Id: DrvChar.cpp 45061 2013-03-18 14:09:03Z vboxsync $ */
2	/** @file
3	* Driver that adapts PDMISTREAM into PDMICHARCONNECTOR / PDMICHARPORT.
4	*
5	* Converts synchronous calls (PDMICHARCONNECTOR::pfnWrite, PDMISTREAM::pfnRead)
6	* into asynchronous ones.
7	*
8	* Note that we don't use a send buffer here to be able to handle
9	* dropping of bytes for xmit at device level.
10	*/
11
12	/*
13	* Copyright (C) 2006-2012 Oracle Corporation
14	*
15	* This file is part of VirtualBox Open Source Edition (OSE), as
16	* available from http://www.virtualbox.org. This file is free software;
17	* you can redistribute it and/or modify it under the terms of the GNU
18	* General Public License (GPL) as published by the Free Software
19	* Foundation, in version 2 as it comes in the "COPYING" file of the
20	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
21	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
22	*/
23
24
25	/*******************************************************************************
26	* Header Files *
27	*******************************************************************************/
28	#define LOG_GROUP LOG_GROUP_DRV_CHAR
29	#include <VBox/vmm/pdmdrv.h>
30	#include <iprt/asm.h>
31	#include <iprt/assert.h>
32	#include <iprt/stream.h>
33	#include <iprt/semaphore.h>
34	#include <iprt/uuid.h>
35
36	#include "VBoxDD.h"
37
38
39	/*******************************************************************************
40	* Defined Constants And Macros *
41	*******************************************************************************/
42	/** Converts a pointer to DRVCHAR::ICharConnector to a PDRVCHAR. */
43	#define PDMICHAR_2_DRVCHAR(pInterface) RT_FROM_MEMBER(pInterface, DRVCHAR, ICharConnector)
44
45
46	/*******************************************************************************
47	* Structures and Typedefs *
48	*******************************************************************************/
49	/**
50	* Char driver instance data.
51	*
52	* @implements PDMICHARCONNECTOR
53	*/
54	typedef struct DRVCHAR
55	{
56	/** Pointer to the driver instance structure. */
57	PPDMDRVINS pDrvIns;
58	/** Pointer to the char port interface of the driver/device above us. */
59	PPDMICHARPORT pDrvCharPort;
60	/** Pointer to the stream interface of the driver below us. */
61	PPDMISTREAM pDrvStream;
62	/** Our char interface. */
63	PDMICHARCONNECTOR ICharConnector;
64	/** Flag to notify the receive thread it should terminate. */
65	volatile bool fShutdown;
66	/** Receive thread ID. */
67	RTTHREAD ReceiveThread;
68	/** Send thread ID. */
69	RTTHREAD SendThread;
70	/** Send event semaphore */
71	RTSEMEVENT SendSem;
72
73	/** Internal send FIFO queue */
74	uint8_t volatile u8SendByte;
75	bool volatile fSending;
76	uint8_t Alignment[2];
77
78	/** Read/write statistics */
79	STAMCOUNTER StatBytesRead;
80	STAMCOUNTER StatBytesWritten;
81	} DRVCHAR, *PDRVCHAR;
82	AssertCompileMemberAlignment(DRVCHAR, StatBytesRead, 8);
83
84
85
86
87	/* -=-=-=-=- IBase -=-=-=-=- */
88
89	/**
90	* @interface_method_impl{PDMIBASE,pfnQueryInterface}
91	*/
92	static DECLCALLBACK(void ) drvCharQueryInterface(PPDMIBASE pInterface, const char pszIID)
93	{
94	PPDMDRVINS pDrvIns = PDMIBASE_2_PDMDRV(pInterface);
95	PDRVCHAR pThis = PDMINS_2_DATA(pDrvIns, PDRVCHAR);
96
97	PDMIBASE_RETURN_INTERFACE(pszIID, PDMIBASE, &pDrvIns->IBase);
98	PDMIBASE_RETURN_INTERFACE(pszIID, PDMICHARCONNECTOR, &pThis->ICharConnector);
99	return NULL;
100	}
101
102
103	/* -=-=-=-=- ICharConnector -=-=-=-=- */
104
105	/** @copydoc PDMICHARCONNECTOR::pfnWrite */
106	static DECLCALLBACK(int) drvCharWrite(PPDMICHARCONNECTOR pInterface, const void *pvBuf, size_t cbWrite)
107	{
108	PDRVCHAR pThis = PDMICHAR_2_DRVCHAR(pInterface);
109	const char pbBuffer = (const char )pvBuf;
110
111	LogFlow(("%s: pvBuf=%#p cbWrite=%d\n", __FUNCTION__, pvBuf, cbWrite));
112
113	for (uint32_t i = 0; i < cbWrite; i++)
114	{
115	if (ASMAtomicXchgBool(&pThis->fSending, true))
116	return VERR_BUFFER_OVERFLOW;
117
118	pThis->u8SendByte = pbBuffer[i];
119	RTSemEventSignal(pThis->SendSem);
120	STAM_COUNTER_INC(&pThis->StatBytesWritten);
121	}
122	return VINF_SUCCESS;
123	}
124
125	/** @copydoc PDMICHARCONNECTOR::pfnSetParameters */
126	static DECLCALLBACK(int) drvCharSetParameters(PPDMICHARCONNECTOR pInterface, unsigned Bps, char chParity, unsigned cDataBits, unsigned cStopBits)
127	{
128	/PDRVCHAR pThis = PDMICHAR_2_DRVCHAR(pInterface); - unused/
129
130	LogFlow(("%s: Bps=%u chParity=%c cDataBits=%u cStopBits=%u\n", __FUNCTION__, Bps, chParity, cDataBits, cStopBits));
131	return VINF_SUCCESS;
132	}
133
134
135	/* -=-=-=-=- receive thread -=-=-=-=- */
136
137	/**
138	* Send thread loop - pushes data down thru the driver chain.
139	*
140	* @returns 0 on success.
141	* @param ThreadSelf Thread handle to this thread.
142	* @param pvUser User argument.
143	*/
144	static DECLCALLBACK(int) drvCharSendLoop(RTTHREAD ThreadSelf, void *pvUser)
145	{
146	PDRVCHAR pThis = (PDRVCHAR)pvUser;
147
148	int rc = VINF_SUCCESS;
149	while (!pThis->fShutdown)
150	{
151	RTMSINTERVAL cMillies = (rc == VERR_TIMEOUT) ? 50 : RT_INDEFINITE_WAIT;
152	rc = RTSemEventWait(pThis->SendSem, cMillies);
153	if ( RT_FAILURE(rc)
154	&& rc != VERR_TIMEOUT)
155	break;
156
157	/*
158	* Write the character to the attached stream (if present).
159	*/
160	if ( pThis->fShutdown
161	\|\| !pThis->pDrvStream)
162	break;
163
164	size_t cbProcessed = 1;
165	uint8_t ch = pThis->u8SendByte;
166	rc = pThis->pDrvStream->pfnWrite(pThis->pDrvStream, &ch, &cbProcessed);
167	if (RT_SUCCESS(rc))
168	{
169	ASMAtomicXchgBool(&pThis->fSending, false);
170	Assert(cbProcessed == 1);
171	}
172	else if (rc == VERR_TIMEOUT)
173	{
174	/* Normal case, just means that the stream didn't accept a new
175	* character before the timeout elapsed. Just retry. */
176
177	/* do not change the rc status here, otherwise the (rc == VERR_TIMEOUT) branch
178	* in the wait above will never get executed */
179	/* rc = VINF_SUCCESS; */
180	}
181	else
182	{
183	LogRel(("Write failed with %Rrc; skipping\n", rc));
184	break;
185	}
186	}
187
188	return VINF_SUCCESS;
189	}
190
191	/* -=-=-=-=- receive thread -=-=-=-=- */
192
193	/**
194	* Receive thread loop.
195	*
196	* @returns 0 on success.
197	* @param ThreadSelf Thread handle to this thread.
198	* @param pvUser User argument.
199	*/
200	static DECLCALLBACK(int) drvCharReceiveLoop(RTTHREAD ThreadSelf, void *pvUser)
201	{
202	PDRVCHAR pThis = (PDRVCHAR)pvUser;
203	char abBuffer[256];
204	char *pbRemaining = abBuffer;
205	size_t cbRemaining = 0;
206	int rc;
207
208	while (!pThis->fShutdown)
209	{
210	if (!cbRemaining)
211	{
212	/* Get block of data from stream driver. */
213	if (pThis->pDrvStream)
214	{
215	pbRemaining = abBuffer;
216	cbRemaining = sizeof(abBuffer);
217	rc = pThis->pDrvStream->pfnRead(pThis->pDrvStream, abBuffer, &cbRemaining);
218	if (RT_FAILURE(rc))
219	{
220	LogFlow(("Read failed with %Rrc\n", rc));
221	break;
222	}
223	}
224	else
225	RTThreadSleep(100);
226	}
227	else
228	{
229	/* Send data to guest. */
230	size_t cbProcessed = cbRemaining;
231	rc = pThis->pDrvCharPort->pfnNotifyRead(pThis->pDrvCharPort, pbRemaining, &cbProcessed);
232	if (RT_SUCCESS(rc))
233	{
234	Assert(cbProcessed);
235	pbRemaining += cbProcessed;
236	cbRemaining -= cbProcessed;
237	STAM_COUNTER_ADD(&pThis->StatBytesRead, cbProcessed);
238	}
239	else if (rc == VERR_TIMEOUT)
240	{
241	/* Normal case, just means that the guest didn't accept a new
242	* character before the timeout elapsed. Just retry. */
243	rc = VINF_SUCCESS;
244	}
245	else
246	{
247	LogFlow(("NotifyRead failed with %Rrc\n", rc));
248	break;
249	}
250	}
251	}
252
253	return VINF_SUCCESS;
254	}
255
256	/**
257	* Set the modem lines.
258	*
259	* @returns VBox status code
260	* @param pInterface Pointer to the interface structure.
261	* @param RequestToSend Set to true if this control line should be made active.
262	* @param DataTerminalReady Set to true if this control line should be made active.
263	*/
264	static DECLCALLBACK(int) drvCharSetModemLines(PPDMICHARCONNECTOR pInterface, bool RequestToSend, bool DataTerminalReady)
265	{
266	/* Nothing to do here. */
267	return VINF_SUCCESS;
268	}
269
270	/**
271	* Sets the TD line into break condition.
272	*
273	* @returns VBox status code.
274	* @param pInterface Pointer to the interface structure containing the called function pointer.
275	* @param fBreak Set to true to let the device send a break false to put into normal operation.
276	* @thread Any thread.
277	*/
278	static DECLCALLBACK(int) drvCharSetBreak(PPDMICHARCONNECTOR pInterface, bool fBreak)
279	{
280	/* Nothing to do here. */
281	return VINF_SUCCESS;
282	}
283
284	/* -=-=-=-=- driver interface -=-=-=-=- */
285
286	/**
287	* Destruct a char driver instance.
288	*
289	* Most VM resources are freed by the VM. This callback is provided so that
290	* any non-VM resources can be freed correctly.
291	*
292	* @param pDrvIns The driver instance data.
293	*/
294	static DECLCALLBACK(void) drvCharDestruct(PPDMDRVINS pDrvIns)
295	{
296	PDRVCHAR pThis = PDMINS_2_DATA(pDrvIns, PDRVCHAR);
297	LogFlow(("%s: iInstance=%d\n", __FUNCTION__, pDrvIns->iInstance));
298	PDMDRV_CHECK_VERSIONS_RETURN_VOID(pDrvIns);
299
300	/*
301	* Tell the threads to shut down.
302	*/
303	pThis->fShutdown = true;
304	if (pThis->SendSem != NIL_RTSEMEVENT)
305	{
306	RTSemEventSignal(pThis->SendSem);
307	pThis->SendSem = NIL_RTSEMEVENT;
308	}
309
310	/*
311	* Wait for the threads.
312	* ASSUMES that PDM destroys the driver chain from the bottom and up.
313	*/
314	if (pThis->ReceiveThread != NIL_RTTHREAD)
315	{
316	int rc = RTThreadWait(pThis->ReceiveThread, 30000, NULL);
317	if (RT_SUCCESS(rc))
318	pThis->ReceiveThread = NIL_RTTHREAD;
319	else
320	LogRel(("Char%d: receive thread did not terminate (%Rrc)\n", pDrvIns->iInstance, rc));
321	}
322
323	if (pThis->SendThread != NIL_RTTHREAD)
324	{
325	int rc = RTThreadWait(pThis->SendThread, 30000, NULL);
326	if (RT_SUCCESS(rc))
327	pThis->SendThread = NIL_RTTHREAD;
328	else
329	LogRel(("Char%d: send thread did not terminate (%Rrc)\n", pDrvIns->iInstance, rc));
330	}
331
332	if (pThis->SendSem != NIL_RTSEMEVENT)
333	{
334	RTSemEventDestroy(pThis->SendSem);
335	pThis->SendSem = NIL_RTSEMEVENT;
336	}
337	}
338
339
340	/**
341	* Construct a char driver instance.
342	*
343	* @copydoc FNPDMDRVCONSTRUCT
344	*/
345	static DECLCALLBACK(int) drvCharConstruct(PPDMDRVINS pDrvIns, PCFGMNODE pCfg, uint32_t fFlags)
346	{
347	PDRVCHAR pThis = PDMINS_2_DATA(pDrvIns, PDRVCHAR);
348	LogFlow(("%s: iInstance=%d\n", __FUNCTION__, pDrvIns->iInstance));
349	PDMDRV_CHECK_VERSIONS_RETURN(pDrvIns);
350
351	/*
352	* Init basic data members and interfaces.
353	*/
354	pThis->fShutdown = false;
355	pThis->ReceiveThread = NIL_RTTHREAD;
356	pThis->SendThread = NIL_RTTHREAD;
357	pThis->SendSem = NIL_RTSEMEVENT;
358	/* IBase. */
359	pDrvIns->IBase.pfnQueryInterface = drvCharQueryInterface;
360	/* ICharConnector. */
361	pThis->ICharConnector.pfnWrite = drvCharWrite;
362	pThis->ICharConnector.pfnSetParameters = drvCharSetParameters;
363	pThis->ICharConnector.pfnSetModemLines = drvCharSetModemLines;
364	pThis->ICharConnector.pfnSetBreak = drvCharSetBreak;
365
366	/*
367	* Get the ICharPort interface of the above driver/device.
368	*/
369	pThis->pDrvCharPort = PDMIBASE_QUERY_INTERFACE(pDrvIns->pUpBase, PDMICHARPORT);
370	if (!pThis->pDrvCharPort)
371	return PDMDrvHlpVMSetError(pDrvIns, VERR_PDM_MISSING_INTERFACE_ABOVE, RT_SRC_POS, N_("Char#%d has no char port interface above"), pDrvIns->iInstance);
372
373	/*
374	* Attach driver below and query its stream interface.
375	*/
376	PPDMIBASE pBase;
377	int rc = PDMDrvHlpAttach(pDrvIns, fFlags, &pBase);
378	if (RT_FAILURE(rc))
379	return rc; /* Don't call PDMDrvHlpVMSetError here as we assume that the driver already set an appropriate error */
380	pThis->pDrvStream = PDMIBASE_QUERY_INTERFACE(pBase, PDMISTREAM);
381	if (!pThis->pDrvStream)
382	return PDMDrvHlpVMSetError(pDrvIns, VERR_PDM_MISSING_INTERFACE_BELOW, RT_SRC_POS, N_("Char#%d has no stream interface below"), pDrvIns->iInstance);
383
384	/*
385	* Don't start the receive thread if the driver doesn't support reading
386	*/
387	if (pThis->pDrvStream->pfnRead)
388	{
389	rc = RTThreadCreate(&pThis->ReceiveThread, drvCharReceiveLoop, (void *)pThis, 0,
390	RTTHREADTYPE_IO, RTTHREADFLAGS_WAITABLE, "CharRecv");
391	if (RT_FAILURE(rc))
392	return PDMDrvHlpVMSetError(pDrvIns, rc, RT_SRC_POS, N_("Char#%d cannot create receive thread"), pDrvIns->iInstance);
393	}
394
395	rc = RTSemEventCreate(&pThis->SendSem);
396	AssertRCReturn(rc, rc);
397
398	rc = RTThreadCreate(&pThis->SendThread, drvCharSendLoop, (void *)pThis, 0,
399	RTTHREADTYPE_IO, RTTHREADFLAGS_WAITABLE, "CharSend");
400	if (RT_FAILURE(rc))
401	return PDMDrvHlpVMSetError(pDrvIns, rc, RT_SRC_POS, N_("Char#%d cannot create send thread"), pDrvIns->iInstance);
402
403
404	PDMDrvHlpSTAMRegisterF(pDrvIns, &pThis->StatBytesWritten, STAMTYPE_COUNTER, STAMVISIBILITY_USED, STAMUNIT_BYTES, "Nr of bytes written", "/Devices/Char%d/Written", pDrvIns->iInstance);
405	PDMDrvHlpSTAMRegisterF(pDrvIns, &pThis->StatBytesRead, STAMTYPE_COUNTER, STAMVISIBILITY_USED, STAMUNIT_BYTES, "Nr of bytes read", "/Devices/Char%d/Read", pDrvIns->iInstance);
406
407	return VINF_SUCCESS;
408	}
409
410
411	/**
412	* Char driver registration record.
413	*/
414	const PDMDRVREG g_DrvChar =
415	{
416	/* u32Version */
417	PDM_DRVREG_VERSION,
418	/* szName */
419	"Char",
420	/* szRCMod */
421	"",
422	/* szR0Mod */
423	"",
424	/* pszDescription */
425	"Generic char driver.",
426	/* fFlags */
427	PDM_DRVREG_FLAGS_HOST_BITS_DEFAULT,
428	/* fClass. */
429	PDM_DRVREG_CLASS_CHAR,
430	/* cMaxInstances */
431	~0U,
432	/* cbInstance */
433	sizeof(DRVCHAR),
434	/* pfnConstruct */
435	drvCharConstruct,
436	/* pfnDestruct */
437	drvCharDestruct,
438	/* pfnRelocate */
439	NULL,
440	/* pfnIOCtl */
441	NULL,
442	/* pfnPowerOn */
443	NULL,
444	/* pfnReset */
445	NULL,
446	/* pfnSuspend */
447	NULL,
448	/* pfnResume */
449	NULL,
450	/* pfnAttach */
451	NULL,
452	/* pfnDetach */
453	NULL,
454	/* pfnPowerOff */
455	NULL,
456	/* pfnSoftReset */
457	NULL,
458	/* u32EndVersion */
459	PDM_DRVREG_VERSION
460	};

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source: vbox/trunk/src/VBox/Devices/Serial/DrvChar.cpp@ 55747

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