diff options
Diffstat (limited to 'src/VBox/Runtime/r3/posix/serialport-posix.cpp')
-rw-r--r-- | src/VBox/Runtime/r3/posix/serialport-posix.cpp | 1228 |
1 files changed, 1228 insertions, 0 deletions
diff --git a/src/VBox/Runtime/r3/posix/serialport-posix.cpp b/src/VBox/Runtime/r3/posix/serialport-posix.cpp new file mode 100644 index 00000000..b2cc25e0 --- /dev/null +++ b/src/VBox/Runtime/r3/posix/serialport-posix.cpp @@ -0,0 +1,1228 @@ +/* $Id: serialport-posix.cpp $ */ +/** @file + * IPRT - Serial Port API, POSIX Implementation. + */ + +/* + * Copyright (C) 2017-2019 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 * +*********************************************************************************************************************************/ +#include <iprt/serialport.h> +#include "internal/iprt.h" + +#include <iprt/asm.h> +#include <iprt/assert.h> +#include <iprt/cdefs.h> +#include <iprt/err.h> +#include <iprt/mem.h> +#include <iprt/string.h> +#include <iprt/thread.h> +#include <iprt/time.h> +#include "internal/magics.h" + +#include <errno.h> +#ifdef RT_OS_SOLARIS +# include <sys/termios.h> +#else +# include <termios.h> +#endif +#include <sys/types.h> +#include <fcntl.h> +#include <string.h> +#include <unistd.h> +#ifdef RT_OS_DARWIN +# include <sys/poll.h> +#else +# include <sys/poll.h> +#endif +#include <sys/ioctl.h> +#include <pthread.h> + +#ifdef RT_OS_LINUX +/* + * TIOCM_LOOP is not defined in the above header files for some reason but in asm/termios.h. + * But inclusion of this file however leads to compilation errors because of redefinition of some + * structs. That's why it is defined here until a better solution is found. + */ +# ifndef TIOCM_LOOP +# define TIOCM_LOOP 0x8000 +# endif +/* For linux custom baudrate code we also need serial_struct */ +# include <linux/serial.h> +#endif /* linux */ + +/** Define fallback if not supported. */ +#if !defined(CMSPAR) +# define CMSPAR 0 +#endif + + +/********************************************************************************************************************************* +* Structures and Typedefs * +*********************************************************************************************************************************/ + +/** + * Internal serial port state. + */ +typedef struct RTSERIALPORTINTERNAL +{ + /** Magic value (RTSERIALPORT_MAGIC). */ + uint32_t u32Magic; + /** Flags given while opening the serial port. */ + uint32_t fOpenFlags; + /** The file descriptor of the serial port. */ + int iFd; + /** The status line monitor thread if enabled. */ + RTTHREAD hMonThrd; + /** Flag whether the monitoring thread should shutdown. */ + volatile bool fMonThrdShutdown; + /** Reading end of wakeup pipe. */ + int iFdPipeR; + /** Writing end of wakeup pipe. */ + int iFdPipeW; + /** Event pending mask. */ + volatile uint32_t fEvtsPending; + /** Flag whether we are in blocking or non blocking mode. */ + bool fBlocking; + /** The current active config (we assume no one changes this behind our back). */ + struct termios PortCfg; + /** Flag whether a custom baud rate was chosen (for hosts supporting this.). */ + bool fBaudrateCust; + /** The custom baud rate. */ + uint32_t uBaudRateCust; +} RTSERIALPORTINTERNAL; +/** Pointer to the internal serial port state. */ +typedef RTSERIALPORTINTERNAL *PRTSERIALPORTINTERNAL; + + +/** + * Baud rate conversion table descriptor. + */ +typedef struct RTSERIALPORTBRATECONVDESC +{ + /** The platform independent baud rate used by the RTSerialPort* API. */ + uint32_t uBaudRateCfg; + /** The speed identifier used in the termios structure. */ + speed_t iSpeedTermios; +} RTSERIALPORTBRATECONVDESC; +/** Pointer to a baud rate converions table descriptor. */ +typedef RTSERIALPORTBRATECONVDESC *PRTSERIALPORTBRATECONVDESC; +/** Pointer to a const baud rate conversion table descriptor. */ +typedef const RTSERIALPORTBRATECONVDESC *PCRTSERIALPORTBRATECONVDESC; + + +/********************************************************************************************************************************* +* Defined Constants And Macros * +*********************************************************************************************************************************/ + +/** The event poller was woken up due to an external interrupt. */ +#define RTSERIALPORT_WAKEUP_PIPE_REASON_INTERRUPT 0x0 +/** The event poller was woken up due to a change in the monitored status lines. */ +#define RTSERIALPORT_WAKEUP_PIPE_REASON_STS_LINE_CHANGED 0x1 +/** The monitor thread encoutnered repeating errors querying the status lines and terminated. */ +#define RTSERIALPORT_WAKEUP_PIPE_REASON_STS_LINE_MONITOR_FAILED 0x2 + + +/********************************************************************************************************************************* +* Global variables * +*********************************************************************************************************************************/ + +/** The baud rate conversion table. */ +static const RTSERIALPORTBRATECONVDESC s_rtSerialPortBaudrateConv[] = +{ + { 50, B50 }, + { 75, B75 }, + { 110, B110 }, + { 134, B134 }, + { 150, B150 }, + { 200, B200 }, + { 300, B300 }, + { 600, B600 }, + { 1200, B1200 }, + { 1800, B1800 }, + { 2400, B2400 }, + { 4800, B4800 }, + { 9600, B9600 }, + { 19200, B19200 }, + { 38400, B38400 }, + { 57600, B57600 }, + { 115200, B115200 } +}; + + + +/********************************************************************************************************************************* +* Internal Functions * +*********************************************************************************************************************************/ + +/** + * Converts the given termios speed identifier to the baud rate used in the API. + * + * @returns Baud rate or 0 if not a standard baud rate + */ +DECLINLINE(uint32_t) rtSerialPortGetBaudrateFromTermiosSpeed(speed_t enmSpeed) +{ + for (unsigned i = 0; i < RT_ELEMENTS(s_rtSerialPortBaudrateConv); i++) + { + if (s_rtSerialPortBaudrateConv[i].iSpeedTermios == enmSpeed) + return s_rtSerialPortBaudrateConv[i].uBaudRateCfg; + } + + return 0; +} + + +/** + * Converts the given baud rate to proper termios speed identifier. + * + * @returns Speed identifier if available or B0 if no matching speed for the baud rate + * could be found. + * @param uBaudRate The baud rate to convert. + * @param pfBaudrateCust Where to store the flag whether a custom baudrate was selected. + */ +DECLINLINE(speed_t) rtSerialPortGetTermiosSpeedFromBaudrate(uint32_t uBaudRate, bool *pfBaudrateCust) +{ + *pfBaudrateCust = false; + + for (unsigned i = 0; i < RT_ELEMENTS(s_rtSerialPortBaudrateConv); i++) + { + if (s_rtSerialPortBaudrateConv[i].uBaudRateCfg == uBaudRate) + return s_rtSerialPortBaudrateConv[i].iSpeedTermios; + } + +#ifdef RT_OS_LINUX + *pfBaudrateCust = true; + return B38400; +#else + return B0; +#endif +} + + +/** + * Tries to set the default config on the given serial port. + * + * @returns IPRT status code. + * @param pThis The internal serial port instance data. + */ +static int rtSerialPortSetDefaultCfg(PRTSERIALPORTINTERNAL pThis) +{ + pThis->fBaudrateCust = false; + pThis->uBaudRateCust = 0; + pThis->PortCfg.c_iflag = INPCK; /* Input parity checking. */ + cfsetispeed(&pThis->PortCfg, B9600); + cfsetospeed(&pThis->PortCfg, B9600); + pThis->PortCfg.c_cflag |= CS8 | CLOCAL; /* 8 data bits, ignore modem control lines. */ + if (pThis->fOpenFlags & RTSERIALPORT_OPEN_F_READ) + pThis->PortCfg.c_cflag |= CREAD; /* Enable receiver. */ + + /* Set to raw input mode. */ + pThis->PortCfg.c_lflag &= ~(ICANON | ECHO | ECHOE | ECHONL | ECHOK | ISIG | IEXTEN); + pThis->PortCfg.c_cc[VMIN] = 0; /* Achieve non-blocking behavior. */ + pThis->PortCfg.c_cc[VTIME] = 0; + + int rc = VINF_SUCCESS; + int rcPsx = tcflush(pThis->iFd, TCIOFLUSH); + if (!rcPsx) + { + rcPsx = tcsetattr(pThis->iFd, TCSANOW, &pThis->PortCfg); + if (rcPsx == -1) + rc = RTErrConvertFromErrno(errno); + + if (RT_SUCCESS(rc)) + { +#ifdef RT_OS_LINUX + if (pThis->fOpenFlags & RTSERIALPORT_OPEN_F_ENABLE_LOOPBACK) + { + int fTiocmSet = TIOCM_LOOP; + rcPsx = ioctl(pThis->iFd, TIOCMBIS, &fTiocmSet); + if (rcPsx == -1) + rc = RTErrConvertFromErrno(errno); + } + else + { + /* Make sure it is clear. */ + int fTiocmClear = TIOCM_LOOP; + rcPsx = ioctl(pThis->iFd, TIOCMBIC, &fTiocmClear); + if (rcPsx == -1 && errno != EINVAL) /* Pseudo terminals don't support loopback mode so ignore an error here. */ + rc = RTErrConvertFromErrno(errno); + } +#else + if (pThis->fOpenFlags & RTSERIALPORT_OPEN_F_ENABLE_LOOPBACK) + return VERR_NOT_SUPPORTED; +#endif + } + } + else + rc = RTErrConvertFromErrno(errno); + + return rc; +} + + +/** + * Converts the given serial port config to the appropriate termios counterpart. + * + * @returns IPRT status code. + * @param pThis The internal serial port instance data. + * @param pCfg Pointer to the serial port config descriptor. + * @param pTermios Pointer to the termios structure to fill. + * @param pfBaudrateCust Where to store the flag whether a custom baudrate was selected. + * @param pErrInfo Additional error to be set when the conversion fails. + */ +static int rtSerialPortCfg2Termios(PRTSERIALPORTINTERNAL pThis, PCRTSERIALPORTCFG pCfg, struct termios *pTermios, + bool *pfBaudrateCust, PRTERRINFO pErrInfo) +{ + RT_NOREF(pErrInfo); /** @todo Make use of the error info. */ + speed_t enmSpeed = rtSerialPortGetTermiosSpeedFromBaudrate(pCfg->uBaudRate, pfBaudrateCust); + if (enmSpeed != B0) + { + tcflag_t const fCFlagMask = (CS5 | CS6 | CS7 | CS8 | CSTOPB | PARENB | PARODD | CMSPAR); + tcflag_t fCFlagNew = 0; + + switch (pCfg->enmDataBitCount) + { + case RTSERIALPORTDATABITS_5BITS: + fCFlagNew |= CS5; + break; + case RTSERIALPORTDATABITS_6BITS: + fCFlagNew |= CS6; + break; + case RTSERIALPORTDATABITS_7BITS: + fCFlagNew |= CS7; + break; + case RTSERIALPORTDATABITS_8BITS: + fCFlagNew |= CS8; + break; + default: + AssertFailed(); + return VERR_INVALID_PARAMETER; + } + + switch (pCfg->enmParity) + { + case RTSERIALPORTPARITY_NONE: + break; + case RTSERIALPORTPARITY_EVEN: + fCFlagNew |= PARENB; + break; + case RTSERIALPORTPARITY_ODD: + fCFlagNew |= PARENB | PARODD; + break; +#if CMSPAR != 0 + case RTSERIALPORTPARITY_MARK: + fCFlagNew |= PARENB | CMSPAR | PARODD; + break; + case RTSERIALPORTPARITY_SPACE: + fCFlagNew |= PARENB | CMSPAR; + break; +#else + case RTSERIALPORTPARITY_MARK: + case RTSERIALPORTPARITY_SPACE: + return VERR_NOT_SUPPORTED; +#endif + default: + AssertFailed(); + return VERR_INVALID_PARAMETER; + } + + switch (pCfg->enmStopBitCount) + { + case RTSERIALPORTSTOPBITS_ONE: + break; + case RTSERIALPORTSTOPBITS_ONEPOINTFIVE: + if (pCfg->enmDataBitCount == RTSERIALPORTDATABITS_5BITS) + fCFlagNew |= CSTOPB; + else + return VERR_NOT_SUPPORTED; + break; + case RTSERIALPORTSTOPBITS_TWO: + if (pCfg->enmDataBitCount != RTSERIALPORTDATABITS_5BITS) + fCFlagNew |= CSTOPB; + else + return VERR_NOT_SUPPORTED; + break; + default: + AssertFailed(); + return VERR_INVALID_PARAMETER; + } + + /* Assign new flags. */ + if (pThis->fOpenFlags & RTSERIALPORT_OPEN_F_READ) + pTermios->c_cflag |= CREAD; /* Enable receiver. */ + pTermios->c_cflag = (pTermios->c_cflag & ~fCFlagMask) | fCFlagNew; + pTermios->c_lflag &= ~(ICANON | ECHO | ECHOE | ECHONL | ECHOK | ISIG | IEXTEN); + pTermios->c_iflag = INPCK; /* Input parity checking. */ + pTermios->c_cc[VMIN] = 0; /* Achieve non-blocking behavior. */ + pTermios->c_cc[VTIME] = 0; + cfsetispeed(pTermios, enmSpeed); + cfsetospeed(pTermios, enmSpeed); + } + else + return VERR_SERIALPORT_INVALID_BAUDRATE; + + return VINF_SUCCESS; +} + + +/** + * Converts the given termios structure to an appropriate serial port config. + * + * @returns IPRT status code. + * @param pThis The internal serial port instance data. + * @param pTermios The termios structure to convert. + * @param pCfg The serial port config to fill in. + */ +static int rtSerialPortTermios2Cfg(PRTSERIALPORTINTERNAL pThis, struct termios *pTermios, PRTSERIALPORTCFG pCfg) +{ + int rc = VINF_SUCCESS; + bool f5DataBits = false; + speed_t enmSpeedIn = cfgetispeed(pTermios); + Assert(enmSpeedIn == cfgetospeed(pTermios)); /* Should always be the same. */ + + if (!pThis->fBaudrateCust) + { + pCfg->uBaudRate = rtSerialPortGetBaudrateFromTermiosSpeed(enmSpeedIn); + if (!pCfg->uBaudRate) + rc = VERR_SERIALPORT_INVALID_BAUDRATE; + } + else + pCfg->uBaudRate = pThis->uBaudRateCust; + + switch (pTermios->c_cflag & CSIZE) + { + case CS5: + pCfg->enmDataBitCount = RTSERIALPORTDATABITS_5BITS; + f5DataBits = true; + break; + case CS6: + pCfg->enmDataBitCount = RTSERIALPORTDATABITS_6BITS; + break; + case CS7: + pCfg->enmDataBitCount = RTSERIALPORTDATABITS_7BITS; + break; + case CS8: + pCfg->enmDataBitCount = RTSERIALPORTDATABITS_8BITS; + break; + default: + AssertFailed(); /* Should not happen. */ + pCfg->enmDataBitCount = RTSERIALPORTDATABITS_INVALID; + rc = RT_FAILURE(rc) ? rc : VERR_INVALID_PARAMETER; + } + + /* Convert parity. */ + if (pTermios->c_cflag & PARENB) + { + /* + * CMSPAR is not supported on all systems, especially OS X. As configuring + * mark/space parity there is not supported and we start from a known config + * when opening the serial port it is not required to check for this here. + */ +#if CMSPAR == 0 + bool fCmsParSet = RT_BOOL(pTermios->c_cflag & CMSPAR); +#else + bool fCmsParSet = false; +#endif + if (pTermios->c_cflag & PARODD) + pCfg->enmParity = fCmsParSet ? RTSERIALPORTPARITY_MARK : RTSERIALPORTPARITY_ODD; + else + pCfg->enmParity = fCmsParSet ? RTSERIALPORTPARITY_SPACE: RTSERIALPORTPARITY_EVEN; + } + else + pCfg->enmParity = RTSERIALPORTPARITY_NONE; + + /* + * 1.5 stop bits are used with a data count of 5 bits when a UART derived from the 8250 + * is used. + */ + if (pTermios->c_cflag & CSTOPB) + pCfg->enmStopBitCount = f5DataBits ? RTSERIALPORTSTOPBITS_ONEPOINTFIVE : RTSERIALPORTSTOPBITS_TWO; + else + pCfg->enmStopBitCount = RTSERIALPORTSTOPBITS_ONE; + + return rc; +} + + +/** + * Wakes up any thread polling for a serial port event with the given reason. + * + * @returns IPRT status code. + * @param pThis The internal serial port instance data. + * @param bWakeupReason The wakeup reason to pass to the event poller. + */ +DECLINLINE(int) rtSerialPortWakeupEvtPoller(PRTSERIALPORTINTERNAL pThis, uint8_t bWakeupReason) +{ + int rcPsx = write(pThis->iFdPipeW, &bWakeupReason, 1); + if (rcPsx != 1) + return RTErrConvertFromErrno(errno); + + return VINF_SUCCESS; +} + + +/** + * The status line monitor thread worker. + * + * @returns IPRT status code. + * @param ThreadSelf Thread handle to this thread. + * @param pvUser User argument. + */ +static DECLCALLBACK(int) rtSerialPortStsLineMonitorThrd(RTTHREAD hThreadSelf, void *pvUser) +{ + RT_NOREF(hThreadSelf); + PRTSERIALPORTINTERNAL pThis = (PRTSERIALPORTINTERNAL)pvUser; + unsigned long const fStsLinesChk = TIOCM_CAR | TIOCM_RNG | TIOCM_DSR | TIOCM_CTS; + int rc = VINF_SUCCESS; + uint32_t fStsLinesOld = 0; + uint32_t cStsLineGetErrors = 0; +#ifdef RT_OS_LINUX + bool fPoll = false; +#endif + + RTThreadUserSignal(hThreadSelf); + + int rcPsx = ioctl(pThis->iFd, TIOCMGET, &fStsLinesOld); + if (rcPsx == -1) + { + ASMAtomicXchgBool(&pThis->fMonThrdShutdown, true); + return RTErrConvertFromErrno(errno); + } + + while ( !pThis->fMonThrdShutdown + && RT_SUCCESS(rc)) + { +# ifdef RT_OS_LINUX + /* + * Wait for status line change. + * + * XXX In Linux, if a thread calls tcsetattr while the monitor thread is + * waiting in ioctl for a modem status change then 8250.c wrongly disables + * modem irqs and so the monitor thread never gets released. The workaround + * is to send a signal after each tcsetattr. + * + * TIOCMIWAIT doesn't work for the DSR line with TIOCM_DSR set + * (see http://lxr.linux.no/#linux+v4.7/drivers/usb/class/cdc-acm.c#L949) + * However as it is possible to query the line state we will not just clear + * the TIOCM_DSR bit from the lines to check but resort to the polling + * approach just like on other hosts. + */ + if (!fPoll) + { + rcPsx = ioctl(pThis->iFd, TIOCMIWAIT, fStsLinesChk); + if (!rcPsx) + { + rc = rtSerialPortWakeupEvtPoller(pThis, RTSERIALPORT_WAKEUP_PIPE_REASON_STS_LINE_CHANGED); + if (RT_FAILURE(rc)) + break; + } + else if (rcPsx == -1 && errno != EINTR) + fPoll = true; + } + else +#endif + { + uint32_t fStsLines = 0; + rcPsx = ioctl(pThis->iFd, TIOCMGET, &fStsLines); + if (!rcPsx) + { + cStsLineGetErrors = 0; /* Reset the error counter once we had one successful query. */ + + if (((fStsLines ^ fStsLinesOld) & fStsLinesChk)) + { + rc = rtSerialPortWakeupEvtPoller(pThis, RTSERIALPORT_WAKEUP_PIPE_REASON_STS_LINE_CHANGED); + if (RT_FAILURE(rc)) + break; + + fStsLinesOld = fStsLines; + } + else /* No change, sleep for a bit. */ + RTThreadSleep(100 /*ms*/); + } + else if (rcPsx == -1 && errno != EINTR) + { + /* + * If querying the status line fails too often we have to shut down the + * thread and notify the user of the serial port. + */ + if (cStsLineGetErrors++ >= 10) + { + rc = RTErrConvertFromErrno(errno); + rtSerialPortWakeupEvtPoller(pThis, RTSERIALPORT_WAKEUP_PIPE_REASON_STS_LINE_MONITOR_FAILED); + break; + } + + RTThreadSleep(100 /*ms*/); + } + } + } + + ASMAtomicXchgBool(&pThis->fMonThrdShutdown, true); + return rc; +} + + +/** + * Creates the status line monitoring thread. + * + * @returns IPRT status code. + * @param pThis The internal serial port instance data. + */ +static int rtSerialPortMonitorThreadCreate(PRTSERIALPORTINTERNAL pThis) +{ + int rc = VINF_SUCCESS; + + /* + * Check whether querying the status lines is supported at all, pseudo terminals + * don't support it so an error returned in that case. + */ + uint32_t fStsLines = 0; + int rcPsx = ioctl(pThis->iFd, TIOCMGET, &fStsLines); + if (!rcPsx) + { + pThis->fMonThrdShutdown = false; + rc = RTThreadCreate(&pThis->hMonThrd, rtSerialPortStsLineMonitorThrd, pThis, 0 /*cbStack*/, + RTTHREADTYPE_IO, RTTHREADFLAGS_WAITABLE, "IPRT-SerPortMon"); + if (RT_SUCCESS(rc)) + { + /* Wait for the thread to start up. */ + rc = RTThreadUserWait(pThis->hMonThrd, 20*RT_MS_1SEC); + if ( rc == VERR_TIMEOUT + || pThis->fMonThrdShutdown) + { + /* Startup failed, try to reap the thread. */ + int rcThrd; + rc = RTThreadWait(pThis->hMonThrd, 20*RT_MS_1SEC, &rcThrd); + if (RT_SUCCESS(rc)) + rc = rcThrd; + else + rc = VERR_INTERNAL_ERROR; + /* The thread is lost otherwise. */ + } + } + } + else if (errno == ENOTTY || errno == EINVAL) + rc = VERR_NOT_SUPPORTED; + else + rc = RTErrConvertFromErrno(errno); + + return rc; +} + + +/** + * Shuts down the status line monitor thread. + * + * @returns nothing. + * @param pThis The internal serial port instance data. + */ +static void rtSerialPortMonitorThreadShutdown(PRTSERIALPORTINTERNAL pThis) +{ + bool fShutDown = ASMAtomicXchgBool(&pThis->fMonThrdShutdown, true); + if (!fShutDown) + { + int rc = RTThreadPoke(pThis->hMonThrd); + AssertRC(rc); + } + + int rcThrd = VINF_SUCCESS; + int rc = RTThreadWait(pThis->hMonThrd, 20*RT_MS_1SEC, &rcThrd); + AssertRC(rc); + AssertRC(rcThrd); +} + + +/** + * The slow path of rtSerialPortSwitchBlockingMode that does the actual switching. + * + * @returns IPRT status code. + * @param pThis The internal serial port instance data. + * @param fBlocking The desired mode of operation. + * @remarks Do not call directly. + */ +static int rtSerialPortSwitchBlockingModeSlow(PRTSERIALPORTINTERNAL pThis, bool fBlocking) +{ + int fFlags = fcntl(pThis->iFd, F_GETFL, 0); + if (fFlags == -1) + return RTErrConvertFromErrno(errno); + + if (fBlocking) + fFlags &= ~O_NONBLOCK; + else + fFlags |= O_NONBLOCK; + if (fcntl(pThis->iFd, F_SETFL, fFlags) == -1) + return RTErrConvertFromErrno(errno); + + pThis->fBlocking = fBlocking; + return VINF_SUCCESS; +} + + +/** + * Switches the serial port to the desired blocking mode if necessary. + * + * @returns IPRT status code. + * @param pThis The internal serial port instance data. + * @param fBlocking The desired mode of operation. + */ +DECLINLINE(int) rtSerialPortSwitchBlockingMode(PRTSERIALPORTINTERNAL pThis, bool fBlocking) +{ + if (pThis->fBlocking != fBlocking) + return rtSerialPortSwitchBlockingModeSlow(pThis, fBlocking); + return VINF_SUCCESS; +} + + +RTDECL(int) RTSerialPortOpen(PRTSERIALPORT phSerialPort, const char *pszPortAddress, uint32_t fFlags) +{ + AssertPtrReturn(phSerialPort, VERR_INVALID_POINTER); + AssertReturn(VALID_PTR(pszPortAddress) && *pszPortAddress != '\0', VERR_INVALID_PARAMETER); + AssertReturn(!(fFlags & ~RTSERIALPORT_OPEN_F_VALID_MASK), VERR_INVALID_PARAMETER); + AssertReturn((fFlags & RTSERIALPORT_OPEN_F_READ) || (fFlags & RTSERIALPORT_OPEN_F_WRITE), + VERR_INVALID_PARAMETER); + + int rc = VINF_SUCCESS; + PRTSERIALPORTINTERNAL pThis = (PRTSERIALPORTINTERNAL)RTMemAllocZ(sizeof(*pThis)); + if (pThis) + { + int fPsxFlags = O_NOCTTY | O_NONBLOCK; + + if ((fFlags & RTSERIALPORT_OPEN_F_READ) && !(fFlags & RTSERIALPORT_OPEN_F_WRITE)) + fPsxFlags |= O_RDONLY; + else if (!(fFlags & RTSERIALPORT_OPEN_F_READ) && (fFlags & RTSERIALPORT_OPEN_F_WRITE)) + fPsxFlags |= O_WRONLY; + else + fPsxFlags |= O_RDWR; + + pThis->u32Magic = RTSERIALPORT_MAGIC; + pThis->fOpenFlags = fFlags; + pThis->fEvtsPending = 0; + pThis->iFd = open(pszPortAddress, fPsxFlags); + pThis->fBlocking = false; + if (pThis->iFd != -1) + { + /* Create wakeup pipe for the event API. */ + int aPipeFds[2]; + int rcPsx = pipe(&aPipeFds[0]); + if (!rcPsx) + { + /* Make the pipes close on exec. */ + pThis->iFdPipeR = aPipeFds[0]; + pThis->iFdPipeW = aPipeFds[1]; + + if (fcntl(pThis->iFdPipeR, F_SETFD, FD_CLOEXEC)) + rc = RTErrConvertFromErrno(errno); + + if ( RT_SUCCESS(rc) + && fcntl(pThis->iFdPipeW, F_SETFD, FD_CLOEXEC)) + rc = RTErrConvertFromErrno(errno); + + if (RT_SUCCESS(rc)) + { + rc = rtSerialPortSetDefaultCfg(pThis); + if ( RT_SUCCESS(rc) + && (fFlags & RTSERIALPORT_OPEN_F_SUPPORT_STATUS_LINE_MONITORING)) + rc = rtSerialPortMonitorThreadCreate(pThis); + + if (RT_SUCCESS(rc)) + { + *phSerialPort = pThis; + return VINF_SUCCESS; + } + } + + close(pThis->iFdPipeR); + close(pThis->iFdPipeW); + } + else + rc = RTErrConvertFromErrno(errno); + + close(pThis->iFd); + } + else + rc = RTErrConvertFromErrno(errno); + + RTMemFree(pThis); + } + else + rc = VERR_NO_MEMORY; + + return rc; +} + + +RTDECL(int) RTSerialPortClose(RTSERIALPORT hSerialPort) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + if (pThis == NIL_RTSERIALPORT) + return VINF_SUCCESS; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + + /* + * Do the cleanup. + */ + AssertReturn(ASMAtomicCmpXchgU32(&pThis->u32Magic, RTSERIALPORT_MAGIC_DEAD, RTSERIALPORT_MAGIC), VERR_INVALID_HANDLE); + + if (pThis->fOpenFlags & RTSERIALPORT_OPEN_F_SUPPORT_STATUS_LINE_MONITORING) + rtSerialPortMonitorThreadShutdown(pThis); + + close(pThis->iFd); + close(pThis->iFdPipeR); + close(pThis->iFdPipeW); + RTMemFree(pThis); + return VINF_SUCCESS; +} + + +RTDECL(RTHCINTPTR) RTSerialPortToNative(RTSERIALPORT hSerialPort) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, -1); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, -1); + + return pThis->iFd; +} + + +RTDECL(int) RTSerialPortRead(RTSERIALPORT hSerialPort, void *pvBuf, size_t cbToRead, size_t *pcbRead) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + AssertPtrReturn(pvBuf, VERR_INVALID_POINTER); + AssertReturn(cbToRead > 0, VERR_INVALID_PARAMETER); + + int rc = rtSerialPortSwitchBlockingMode(pThis, true); + if (RT_SUCCESS(rc)) + { + /* + * Attempt read. + */ + ssize_t cbRead = read(pThis->iFd, pvBuf, cbToRead); + if (cbRead >= 0) + { + if (pcbRead) + /* caller can handle partial read. */ + *pcbRead = cbRead; + else + { + /* Caller expects all to be read. */ + while ((ssize_t)cbToRead > cbRead) + { + ssize_t cbReadPart = read(pThis->iFd, (uint8_t *)pvBuf + cbRead, cbToRead - cbRead); + if (cbReadPart < 0) + return RTErrConvertFromErrno(errno); + + cbRead += cbReadPart; + } + } + } + else + rc = RTErrConvertFromErrno(errno); + } + + return rc; +} + + +RTDECL(int) RTSerialPortReadNB(RTSERIALPORT hSerialPort, void *pvBuf, size_t cbToRead, size_t *pcbRead) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + AssertPtrReturn(pvBuf, VERR_INVALID_POINTER); + AssertReturn(cbToRead > 0, VERR_INVALID_PARAMETER); + AssertPtrReturn(pcbRead, VERR_INVALID_POINTER); + + *pcbRead = 0; + + int rc = rtSerialPortSwitchBlockingMode(pThis, false); + if (RT_SUCCESS(rc)) + { + ssize_t cbThisRead = read(pThis->iFd, pvBuf, cbToRead); + if (cbThisRead > 0) + { + /* + * The read data needs to be scanned for the BREAK condition marker encoded in the data stream, + * if break detection was enabled during open. + */ + if (pThis->fOpenFlags & RTSERIALPORT_OPEN_F_DETECT_BREAK_CONDITION) + { /** @todo */ } + + *pcbRead = cbThisRead; + } + else if (cbThisRead == 0 || errno == EAGAIN || errno == EWOULDBLOCK) + rc = VINF_TRY_AGAIN; + else + rc = RTErrConvertFromErrno(errno); + } + + return rc; +} + + +RTDECL(int) RTSerialPortWrite(RTSERIALPORT hSerialPort, const void *pvBuf, size_t cbToWrite, size_t *pcbWritten) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + AssertPtrReturn(pvBuf, VERR_INVALID_POINTER); + AssertReturn(cbToWrite > 0, VERR_INVALID_PARAMETER); + + int rc = rtSerialPortSwitchBlockingMode(pThis, true); + if (RT_SUCCESS(rc)) + { + /* + * Attempt write. + */ + ssize_t cbWritten = write(pThis->iFd, pvBuf, cbToWrite); + if (cbWritten >= 0) + { + if (pcbWritten) + /* caller can handle partial write. */ + *pcbWritten = cbWritten; + else + { + /* Caller expects all to be written. */ + while ((ssize_t)cbToWrite > cbWritten) + { + ssize_t cbWrittenPart = write(pThis->iFd, (const uint8_t *)pvBuf + cbWritten, cbToWrite - cbWritten); + if (cbWrittenPart < 0) + return RTErrConvertFromErrno(errno); + cbWritten += cbWrittenPart; + } + } + } + } + + return rc; +} + + +RTDECL(int) RTSerialPortWriteNB(RTSERIALPORT hSerialPort, const void *pvBuf, size_t cbToWrite, size_t *pcbWritten) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + AssertPtrReturn(pvBuf, VERR_INVALID_POINTER); + AssertReturn(cbToWrite > 0, VERR_INVALID_PARAMETER); + AssertPtrReturn(pcbWritten, VERR_INVALID_POINTER); + + *pcbWritten = 0; + + int rc = rtSerialPortSwitchBlockingMode(pThis, false); + if (RT_SUCCESS(rc)) + { + ssize_t cbThisWrite = write(pThis->iFd, pvBuf, cbToWrite); + if (cbThisWrite > 0) + *pcbWritten = cbThisWrite; + else if (cbThisWrite == 0 || errno == EAGAIN || errno == EWOULDBLOCK) + rc = VINF_TRY_AGAIN; + else + rc = RTErrConvertFromErrno(errno); + } + + return rc; +} + + +RTDECL(int) RTSerialPortCfgQueryCurrent(RTSERIALPORT hSerialPort, PRTSERIALPORTCFG pCfg) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + + return rtSerialPortTermios2Cfg(pThis, &pThis->PortCfg, pCfg); +} + + +RTDECL(int) RTSerialPortCfgSet(RTSERIALPORT hSerialPort, PCRTSERIALPORTCFG pCfg, PRTERRINFO pErrInfo) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + + struct termios PortCfgNew; RT_ZERO(PortCfgNew); + bool fBaudrateCust = false; + int rc = rtSerialPortCfg2Termios(pThis, pCfg, &PortCfgNew, &fBaudrateCust, pErrInfo); + if (RT_SUCCESS(rc)) + { + int rcPsx = tcflush(pThis->iFd, TCIOFLUSH); + if (!rcPsx) + { +#ifdef RT_OS_LINUX + if (fBaudrateCust) + { + struct serial_struct SerLnx; + rcPsx = ioctl(pThis->iFd, TIOCGSERIAL, &SerLnx); + if (!rcPsx) + { + SerLnx.custom_divisor = SerLnx.baud_base / pCfg->uBaudRate; + if (!SerLnx.custom_divisor) + SerLnx.custom_divisor = 1; + SerLnx.flags &= ~ASYNC_SPD_MASK; + SerLnx.flags |= ASYNC_SPD_CUST; + rcPsx = ioctl(pThis->iFd, TIOCSSERIAL, &SerLnx); + } + } +#else /* !RT_OS_LINUX */ + /* Hosts not supporting custom baud rates should already fail in rtSerialPortCfg2Termios(). */ + AssertMsgFailed(("Should not get here!\n")); +#endif /* !RT_OS_LINUX */ + pThis->fBaudrateCust = fBaudrateCust; + pThis->uBaudRateCust = pCfg->uBaudRate; + + if (!rcPsx) + rcPsx = tcsetattr(pThis->iFd, TCSANOW, &PortCfgNew); + if (rcPsx == -1) + rc = RTErrConvertFromErrno(errno); + else + memcpy(&pThis->PortCfg, &PortCfgNew, sizeof(struct termios)); + +#ifdef RT_OS_LINUX + /* + * XXX In Linux, if a thread calls tcsetattr while the monitor thread is + * waiting in ioctl for a modem status change then 8250.c wrongly disables + * modem irqs and so the monitor thread never gets released. The workaround + * is to send a signal after each tcsetattr. + */ + if (pThis->fOpenFlags & RTSERIALPORT_OPEN_F_SUPPORT_STATUS_LINE_MONITORING) + RTThreadPoke(pThis->hMonThrd); +#endif + } + else + rc = RTErrConvertFromErrno(errno); + } + + return rc; +} + + +RTDECL(int) RTSerialPortEvtPoll(RTSERIALPORT hSerialPort, uint32_t fEvtMask, uint32_t *pfEvtsRecv, + RTMSINTERVAL msTimeout) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + AssertReturn(!(fEvtMask & ~RTSERIALPORT_EVT_F_VALID_MASK), VERR_INVALID_PARAMETER); + AssertPtrReturn(pfEvtsRecv, VERR_INVALID_POINTER); + + *pfEvtsRecv = 0; + + fEvtMask |= RTSERIALPORT_EVT_F_STATUS_LINE_MONITOR_FAILED; /* This will be reported always, no matter what the caller wants. */ + + /* Return early if there are events pending from previous calls which weren't fetched yet. */ + for (;;) + { + uint32_t fEvtsPending = ASMAtomicReadU32(&pThis->fEvtsPending); + if (fEvtsPending & fEvtMask) + { + *pfEvtsRecv = fEvtsPending & fEvtMask; + /* Write back, repeat the whole procedure if someone else raced us. */ + if (ASMAtomicCmpXchgU32(&pThis->fEvtsPending, fEvtsPending & ~fEvtMask, fEvtsPending)) + return VINF_SUCCESS; + } + else + break; + } + + int rc = rtSerialPortSwitchBlockingMode(pThis, false); + if (RT_SUCCESS(rc)) + { + struct pollfd aPollFds[2]; RT_ZERO(aPollFds); + aPollFds[0].fd = pThis->iFd; + aPollFds[0].events = POLLERR | POLLHUP; + aPollFds[0].revents = 0; + if ( (pThis->fOpenFlags & RTSERIALPORT_OPEN_F_READ) + && (fEvtMask & RTSERIALPORT_EVT_F_DATA_RX)) + aPollFds[0].events |= POLLIN; + if ( (pThis->fOpenFlags & RTSERIALPORT_OPEN_F_WRITE) + && (fEvtMask & RTSERIALPORT_EVT_F_DATA_TX)) + aPollFds[0].events |= POLLOUT; + + aPollFds[1].fd = pThis->iFdPipeR; + aPollFds[1].events = POLLIN | POLLERR | POLLHUP; + aPollFds[1].revents = 0; + + int rcPsx = 0; + int msTimeoutLeft = msTimeout == RT_INDEFINITE_WAIT ? -1 : msTimeout; + while (msTimeoutLeft != 0) + { + uint64_t tsPollStart = RTTimeMilliTS(); + + rcPsx = poll(&aPollFds[0], RT_ELEMENTS(aPollFds), msTimeoutLeft); + if (rcPsx != -1 || errno != EINTR) + break; + /* Restart when getting interrupted. */ + if (msTimeoutLeft > -1) + { + uint64_t tsPollEnd = RTTimeMilliTS(); + uint64_t tsPollSpan = tsPollEnd - tsPollStart; + msTimeoutLeft -= RT_MIN(tsPollSpan, (uint32_t)msTimeoutLeft); + } + } + + uint32_t fEvtsPending = 0; + if (rcPsx < 0 && errno != EINTR) + rc = RTErrConvertFromErrno(errno); + else if (rcPsx > 0) + { + if (aPollFds[0].revents != 0) + { + fEvtsPending |= (aPollFds[0].revents & POLLIN) ? RTSERIALPORT_EVT_F_DATA_RX : 0; + fEvtsPending |= (aPollFds[0].revents & POLLOUT) ? RTSERIALPORT_EVT_F_DATA_TX : 0; + /** @todo BREAK condition detection. */ + } + + if (aPollFds[1].revents != 0) + { + AssertReturn(!(aPollFds[1].revents & (POLLHUP | POLLERR | POLLNVAL)), VERR_INTERNAL_ERROR); + Assert(aPollFds[1].revents & POLLIN); + + uint8_t bWakeupReason = 0; + ssize_t cbRead = read(pThis->iFdPipeR, &bWakeupReason, 1); + if (cbRead == 1) + { + switch (bWakeupReason) + { + case RTSERIALPORT_WAKEUP_PIPE_REASON_INTERRUPT: + rc = VERR_INTERRUPTED; + break; + case RTSERIALPORT_WAKEUP_PIPE_REASON_STS_LINE_CHANGED: + fEvtsPending |= RTSERIALPORT_EVT_F_STATUS_LINE_CHANGED; + break; + case RTSERIALPORT_WAKEUP_PIPE_REASON_STS_LINE_MONITOR_FAILED: + fEvtsPending |= RTSERIALPORT_EVT_F_STATUS_LINE_MONITOR_FAILED; + break; + default: + AssertFailed(); + rc = VERR_INTERNAL_ERROR; + } + } + else + rc = VERR_INTERNAL_ERROR; + } + } + else + rc = VERR_TIMEOUT; + + *pfEvtsRecv = fEvtsPending & fEvtMask; + fEvtsPending &= ~fEvtMask; + ASMAtomicOrU32(&pThis->fEvtsPending, fEvtsPending); + } + + return rc; +} + + +RTDECL(int) RTSerialPortEvtPollInterrupt(RTSERIALPORT hSerialPort) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + + return rtSerialPortWakeupEvtPoller(pThis, RTSERIALPORT_WAKEUP_PIPE_REASON_INTERRUPT); +} + + +RTDECL(int) RTSerialPortChgBreakCondition(RTSERIALPORT hSerialPort, bool fSet) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + + int rc = VINF_SUCCESS; + int rcPsx = ioctl(pThis->iFd, fSet ? TIOCSBRK : TIOCCBRK); + if (rcPsx == -1) + rc = RTErrConvertFromErrno(errno); + + return rc; +} + + +RTDECL(int) RTSerialPortChgStatusLines(RTSERIALPORT hSerialPort, uint32_t fClear, uint32_t fSet) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + + int rc = VINF_SUCCESS; + int fTiocmSet = 0; + int fTiocmClear = 0; + + if (fClear & RTSERIALPORT_CHG_STS_LINES_F_RTS) + fTiocmClear |= TIOCM_RTS; + if (fClear & RTSERIALPORT_CHG_STS_LINES_F_DTR) + fTiocmClear |= TIOCM_DTR; + + if (fSet & RTSERIALPORT_CHG_STS_LINES_F_RTS) + fTiocmSet |= TIOCM_RTS; + if (fSet & RTSERIALPORT_CHG_STS_LINES_F_DTR) + fTiocmSet |= TIOCM_DTR; + + int rcPsx = ioctl(pThis->iFd, TIOCMBIS, &fTiocmSet); + if (!rcPsx) + { + rcPsx = ioctl(pThis->iFd, TIOCMBIC, &fTiocmClear); + if (rcPsx == -1) + rc = RTErrConvertFromErrno(errno); + } + return rc; +} + + +RTDECL(int) RTSerialPortQueryStatusLines(RTSERIALPORT hSerialPort, uint32_t *pfStsLines) +{ + PRTSERIALPORTINTERNAL pThis = hSerialPort; + AssertPtrReturn(pThis, VERR_INVALID_PARAMETER); + AssertReturn(pThis->u32Magic == RTSERIALPORT_MAGIC, VERR_INVALID_HANDLE); + AssertPtrReturn(pfStsLines, VERR_INVALID_POINTER); + + *pfStsLines = 0; + + int rc = VINF_SUCCESS; + int fStsLines = 0; + int rcPsx = ioctl(pThis->iFd, TIOCMGET, &fStsLines); + if (!rcPsx) + { + /* This resets the status line event pending flag. */ + for (;;) + { + uint32_t fEvtsPending = ASMAtomicReadU32(&pThis->fEvtsPending); + if (ASMAtomicCmpXchgU32(&pThis->fEvtsPending, fEvtsPending & ~RTSERIALPORT_EVT_F_STATUS_LINE_CHANGED, fEvtsPending)) + break; + } + + *pfStsLines |= (fStsLines & TIOCM_CAR) ? RTSERIALPORT_STS_LINE_DCD : 0; + *pfStsLines |= (fStsLines & TIOCM_RNG) ? RTSERIALPORT_STS_LINE_RI : 0; + *pfStsLines |= (fStsLines & TIOCM_DSR) ? RTSERIALPORT_STS_LINE_DSR : 0; + *pfStsLines |= (fStsLines & TIOCM_CTS) ? RTSERIALPORT_STS_LINE_CTS : 0; + } + else + rc = RTErrConvertFromErrno(errno); + + return rc; +} + |