-/*
- * Generic uart / rs232/ serial port library
- *
- * Copyright (c) 2013, Roel Verdult
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the copyright holders nor the
- * names of its contributors may be used to endorse or promote products
- * derived from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- * @file uart.c
- * @brief
- *
- */
-
-#include "uart.h"
-
-// Test if we are dealing with unix operating systems
-#ifndef _WIN32
-
-#include <termios.h>
-typedef struct termios term_info;
-typedef struct {
- int fd; // Serial port file descriptor
- term_info tiOld; // Terminal info before using the port
- term_info tiNew; // Terminal info during the transaction
-} serial_port_unix;
-
-// Set time-out on 30 miliseconds
-const struct timeval timeout = {
- .tv_sec = 0, // 0 second
- .tv_usec = 30000 // 30000 micro seconds
-};
-
-serial_port uart_open(const char* pcPortName)
-{
- serial_port_unix* sp = malloc(sizeof(serial_port_unix));
- if (sp == 0) return INVALID_SERIAL_PORT;
-
- sp->fd = open(pcPortName, O_RDWR | O_NOCTTY | O_NDELAY | O_NONBLOCK);
- if(sp->fd == -1) {
- uart_close(sp);
- return INVALID_SERIAL_PORT;
- }
-
- // Finally figured out a way to claim a serial port interface under unix
- // We just try to set a (advisory) lock on the file descriptor
- struct flock fl;
- fl.l_type = F_WRLCK;
- fl.l_whence = SEEK_SET;
- fl.l_start = 0;
- fl.l_len = 0;
- fl.l_pid = getpid();
-
- // Does the system allows us to place a lock on this file descriptor
- if (fcntl(sp->fd, F_SETLK, &fl) == -1) {
- // A conflicting lock is held by another process
- free(sp);
- return CLAIMED_SERIAL_PORT;
- }
-
- // Try to retrieve the old (current) terminal info struct
- if(tcgetattr(sp->fd,&sp->tiOld) == -1) {
- uart_close(sp);
- return INVALID_SERIAL_PORT;
- }
-
- // Duplicate the (old) terminal info struct
- sp->tiNew = sp->tiOld;
-
- // Configure the serial port
- sp->tiNew.c_cflag = CS8 | CLOCAL | CREAD;
- sp->tiNew.c_iflag = IGNPAR;
- sp->tiNew.c_oflag = 0;
- sp->tiNew.c_lflag = 0;
-
- // Block until n bytes are received
- sp->tiNew.c_cc[VMIN] = 0;
- // Block until a timer expires (n * 100 mSec.)
- sp->tiNew.c_cc[VTIME] = 0;
-
- // Try to set the new terminal info struct
- if(tcsetattr(sp->fd,TCSANOW,&sp->tiNew) == -1) {
- uart_close(sp);
- return INVALID_SERIAL_PORT;
- }
-
- // Flush all lingering data that may exist
- tcflush(sp->fd, TCIOFLUSH);
-
- return sp;
-}
-
-void uart_close(const serial_port sp) {
- serial_port_unix* spu = (serial_port_unix*)sp;
- tcflush(spu->fd,TCIOFLUSH);
- tcsetattr(spu->fd,TCSANOW,&(spu->tiOld));
- struct flock fl;
- fl.l_type = F_UNLCK;
- fl.l_whence = SEEK_SET;
- fl.l_start = 0;
- fl.l_len = 0;
- fl.l_pid = getpid();
- fcntl(spu->fd, F_SETLK, &fl);
- close(spu->fd);
- free(sp);
-}
-
-bool uart_set_speed(serial_port sp, const uint32_t uiPortSpeed) {
- const serial_port_unix* spu = (serial_port_unix*)sp;
- speed_t stPortSpeed;
- switch (uiPortSpeed) {
- case 0: stPortSpeed = B0; break;
- case 50: stPortSpeed = B50; break;
- case 75: stPortSpeed = B75; break;
- case 110: stPortSpeed = B110; break;
- case 134: stPortSpeed = B134; break;
- case 150: stPortSpeed = B150; break;
- case 300: stPortSpeed = B300; break;
- case 600: stPortSpeed = B600; break;
- case 1200: stPortSpeed = B1200; break;
- case 1800: stPortSpeed = B1800; break;
- case 2400: stPortSpeed = B2400; break;
- case 4800: stPortSpeed = B4800; break;
- case 9600: stPortSpeed = B9600; break;
- case 19200: stPortSpeed = B19200; break;
- case 38400: stPortSpeed = B38400; break;
-# ifdef B57600
- case 57600: stPortSpeed = B57600; break;
-# endif
-# ifdef B115200
- case 115200: stPortSpeed = B115200; break;
-# endif
-# ifdef B230400
- case 230400: stPortSpeed = B230400; break;
-# endif
-# ifdef B460800
- case 460800: stPortSpeed = B460800; break;
-# endif
-# ifdef B921600
- case 921600: stPortSpeed = B921600; break;
-# endif
- default: return false;
- };
- struct termios ti;
- if (tcgetattr(spu->fd,&ti) == -1) return false;
- // Set port speed (Input and Output)
- cfsetispeed(&ti,stPortSpeed);
- cfsetospeed(&ti,stPortSpeed);
- return (tcsetattr(spu->fd,TCSANOW,&ti) != -1);
-}
-
-uint32_t uart_get_speed(const serial_port sp) {
- struct termios ti;
- uint32_t uiPortSpeed;
- const serial_port_unix* spu = (serial_port_unix*)sp;
- if (tcgetattr(spu->fd,&ti) == -1) return 0;
- // Set port speed (Input)
- speed_t stPortSpeed = cfgetispeed(&ti);
- switch (stPortSpeed) {
- case B0: uiPortSpeed = 0; break;
- case B50: uiPortSpeed = 50; break;
- case B75: uiPortSpeed = 75; break;
- case B110: uiPortSpeed = 110; break;
- case B134: uiPortSpeed = 134; break;
- case B150: uiPortSpeed = 150; break;
- case B300: uiPortSpeed = 300; break;
- case B600: uiPortSpeed = 600; break;
- case B1200: uiPortSpeed = 1200; break;
- case B1800: uiPortSpeed = 1800; break;
- case B2400: uiPortSpeed = 2400; break;
- case B4800: uiPortSpeed = 4800; break;
- case B9600: uiPortSpeed = 9600; break;
- case B19200: uiPortSpeed = 19200; break;
- case B38400: uiPortSpeed = 38400; break;
-# ifdef B57600
- case B57600: uiPortSpeed = 57600; break;
-# endif
-# ifdef B115200
- case B115200: uiPortSpeed = 115200; break;
-# endif
-# ifdef B230400
- case B230400: uiPortSpeed = 230400; break;
-# endif
-# ifdef B460800
- case B460800: uiPortSpeed = 460800; break;
-# endif
-# ifdef B921600
- case B921600: uiPortSpeed = 921600; break;
-# endif
- default: return 0;
- };
- return uiPortSpeed;
-}
-
-bool uart_set_parity(serial_port sp, serial_port_parity spp) {
- struct termios ti;
- const serial_port_unix* spu = (serial_port_unix*)sp;
- if (tcgetattr(spu->fd,&ti) == -1) return false;
- switch(spp) {
- case SP_INVALID: return false;
- case SP_NONE: ti.c_cflag &= ~(PARENB | PARODD); break;
- case SP_EVEN: ti.c_cflag |= PARENB; ti.c_cflag &= ~(PARODD); break;
- case SP_ODD: ti.c_cflag |= PARENB | PARODD; break;
- }
- return (tcsetattr(spu->fd,TCSANOW,&ti) != -1);
-}
-
-serial_port_parity uart_get_parity(const serial_port sp) {
- struct termios ti;
- const serial_port_unix* spu = (serial_port_unix*)sp;
- if (tcgetattr(spu->fd,&ti) == -1) return SP_INVALID;
-
- if (ti.c_cflag & PARENB) {
- if (ti.c_cflag & PARODD) {
- return SP_ODD;
- } else {
- return SP_EVEN;
- }
- } else {
- return SP_NONE;
- }
-}
-
-bool uart_cts(const serial_port sp) {
- char status;
- if (ioctl(((serial_port_unix*)sp)->fd,TIOCMGET,&status) < 0) return false;
- return (status & TIOCM_CTS);
-}
-
-bool uart_receive(const serial_port sp, byte_t* pbtRx, size_t* pszRxLen) {
-
- int res;
- int byteCount;
- fd_set rfds;
- struct timeval tv;
-
- // Reset the output count
- *pszRxLen = 0;
-
- do {
- // Reset file descriptor
- FD_ZERO(&rfds);
- FD_SET(((serial_port_unix*)sp)->fd,&rfds);
- tv = timeout;
- res = select(((serial_port_unix*)sp)->fd+1, &rfds, NULL, NULL, &tv);
-
- // Read error
- if (res < 0) {
- return false;
- }
-
- // Read time-out
- if (res == 0) {
- if (*pszRxLen == 0) {
- // Error, we received no data
- return false;
- } else {
- // We received some data, but nothing more is available
- return true;
- }
- }
-
- // Retrieve the count of the incoming bytes
- res = ioctl(((serial_port_unix*)sp)->fd, FIONREAD, &byteCount);
- if (res < 0) return false;
-
- // There is something available, read the data
- res = read(((serial_port_unix*)sp)->fd,pbtRx+(*pszRxLen),byteCount);
-
- // Stop if the OS has some troubles reading the data
- if (res <= 0) return false;
-
- *pszRxLen += res;
-
- if(res==byteCount)
- return true;
-
- } while (byteCount);
-
- return true;
-}
-
-bool uart_send(const serial_port sp, const byte_t* pbtTx, const size_t szTxLen) {
- int32_t res;
- size_t szPos = 0;
- fd_set rfds;
- struct timeval tv;
-
- while (szPos < szTxLen) {
- // Reset file descriptor
- FD_ZERO(&rfds);
- FD_SET(((serial_port_unix*)sp)->fd,&rfds);
- tv = timeout;
- res = select(((serial_port_unix*)sp)->fd+1, NULL, &rfds, NULL, &tv);
-
- // Write error
- if (res < 0) {
- return false;
- }
-
- // Write time-out
- if (res == 0) {
- return false;
- }
-
- // Send away the bytes
- res = write(((serial_port_unix*)sp)->fd,pbtTx+szPos,szTxLen-szPos);
-
- // Stop if the OS has some troubles sending the data
- if (res <= 0) return false;
-
- szPos += res;
- }
- return true;
-}
-
-#else
-// The windows serial port implementation
-
-typedef struct {
- HANDLE hPort; // Serial port handle
- DCB dcb; // Device control settings
- COMMTIMEOUTS ct; // Serial port time-out configuration
-} serial_port_windows;
-
-void upcase(char *p) {
- while(*p != '\0') {
- if(*p >= 97 && *p <= 122) {
- *p -= 32;
- }
- ++p;
- }
-}
-
-serial_port uart_open(const char* pcPortName) {
- char acPortName[255];
- serial_port_windows* sp = malloc(sizeof(serial_port_windows));
-
- // Copy the input "com?" to "\\.\COM?" format
- sprintf(acPortName,"\\\\.\\%s",pcPortName);
- upcase(acPortName);
-
- // Try to open the serial port
- sp->hPort = CreateFileA(acPortName,GENERIC_READ|GENERIC_WRITE,0,NULL,OPEN_EXISTING,0,NULL);
- if (sp->hPort == INVALID_HANDLE_VALUE) {
- uart_close(sp);
- return INVALID_SERIAL_PORT;
- }
-
- // Prepare the device control
- memset(&sp->dcb, 0, sizeof(DCB));
- sp->dcb.DCBlength = sizeof(DCB);
- if(!BuildCommDCBA("baud=9600 data=8 parity=N stop=1",&sp->dcb)) {
- uart_close(sp);
- return INVALID_SERIAL_PORT;
- }
-
- // Update the active serial port
- if(!SetCommState(sp->hPort,&sp->dcb)) {
- uart_close(sp);
- return INVALID_SERIAL_PORT;
- }
-
- sp->ct.ReadIntervalTimeout = 0;
- sp->ct.ReadTotalTimeoutMultiplier = 0;
- sp->ct.ReadTotalTimeoutConstant = 30;
- sp->ct.WriteTotalTimeoutMultiplier = 0;
- sp->ct.WriteTotalTimeoutConstant = 30;
-
- if(!SetCommTimeouts(sp->hPort,&sp->ct)) {
- uart_close(sp);
- return INVALID_SERIAL_PORT;
- }
-
- PurgeComm(sp->hPort, PURGE_RXABORT | PURGE_RXCLEAR);
-
- return sp;
-}
-
-void uart_close(const serial_port sp) {
- CloseHandle(((serial_port_windows*)sp)->hPort);
- free(sp);
-}
-
-bool uart_set_speed(serial_port sp, const uint32_t uiPortSpeed) {
- serial_port_windows* spw;
- spw = (serial_port_windows*)sp;
- spw->dcb.BaudRate = uiPortSpeed;
- return SetCommState(spw->hPort, &spw->dcb);
-}
-
-uint32_t uart_get_speed(const serial_port sp) {
- const serial_port_windows* spw = (serial_port_windows*)sp;
- if (!GetCommState(spw->hPort, (serial_port)&spw->dcb)) {
- return spw->dcb.BaudRate;
- }
- return 0;
-}
-
-bool uart_receive(const serial_port sp, byte_t* pbtRx, size_t* pszRxLen) {
- ReadFile(((serial_port_windows*)sp)->hPort,pbtRx,*pszRxLen,(LPDWORD)pszRxLen,NULL);
- return (*pszRxLen != 0);
-}
-
-bool uart_send(const serial_port sp, const byte_t* pbtTx, const size_t szTxLen) {
- DWORD dwTxLen = 0;
- return WriteFile(((serial_port_windows*)sp)->hPort,pbtTx,szTxLen,&dwTxLen,NULL);
- return (dwTxLen != 0);
-}
-
-#endif