]> sigrok.org Git - libserialport.git/commitdiff
Initial version. Builds for Linux and Windows.
authorMartin Ling <redacted>
Sat, 27 Apr 2013 22:35:45 +0000 (23:35 +0100)
committerMartin Ling <redacted>
Sun, 27 Oct 2013 10:56:22 +0000 (10:56 +0000)
serialport.c [new file with mode: 0644]
serialport.h [new file with mode: 0644]

diff --git a/serialport.c b/serialport.c
new file mode 100644 (file)
index 0000000..c89f44e
--- /dev/null
@@ -0,0 +1,568 @@
+/*
+ * This file is part of the libserialport project.
+ *
+ * Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
+ * Copyright (C) 2010-2012 Uwe Hermann <uwe@hermann-uwe.de>
+ * Copyright (C) 2013 Martin Ling <martin-libserialport@earth.li>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#ifdef _WIN32
+#include <windows.h>
+#else
+#include <glob.h>
+#include <termios.h>
+#include <sys/ioctl.h>
+#endif
+#include <stdlib.h>
+#include <errno.h>
+
+#include "serialport.h"
+
+static int sp_validate_port(struct sp_port *port)
+{
+       if (port == NULL)
+               return 0;
+#ifdef _WIN32
+       if (port->hdl == INVALID_HANDLE_VALUE)
+               return 0;
+#else
+       if (port->fd < 0)
+               return 0;
+#endif
+       return 1;
+}
+
+#define CHECK_PORT() do { if (!sp_validate_port(port)) return SP_ERR_ARG; } while (0)
+
+/**
+ * Open the specified serial port.
+ *
+ * @param port Pointer to empty port structure allocated by caller.
+ * @param portname Name of port to open.
+ * @param flags Flags to use when opening the serial port. Possible flags
+ *              are: SP_MODE_RDWR, SP_MODE_RDONLY, SP_MODE_NONBLOCK.
+ *
+ * @return SP_OK on success, SP_ERR_FAIL on failure,
+ *         or SP_ERR_ARG if an invalid port or name is passed.
+ */
+int sp_open(struct sp_port *port, char *portname, int flags)
+{
+       if (!port)
+               return SP_ERR_ARG;
+
+       if (!portname)
+               return SP_ERR_ARG;
+
+       port->name = portname;
+
+#ifdef _WIN32
+       DWORD desired_access = 0, flags_and_attributes = 0;
+       /* Map 'flags' to the OS-specific settings. */
+       desired_access |= GENERIC_READ;
+       flags_and_attributes = FILE_ATTRIBUTE_NORMAL;
+       if (flags & SP_MODE_RDWR)
+               desired_access |= GENERIC_WRITE;
+       if (flags & SP_MODE_NONBLOCK)
+               flags_and_attributes |= FILE_FLAG_OVERLAPPED;
+
+       port->hdl = CreateFile(port->name, desired_access, 0, 0,
+                        OPEN_EXISTING, flags_and_attributes, 0);
+       if (port->hdl == INVALID_HANDLE_VALUE)
+               return SP_ERR_FAIL;
+#else
+       int flags_local = 0;
+       /* Map 'flags' to the OS-specific settings. */
+       if (flags & SP_MODE_RDWR)
+               flags_local |= O_RDWR;
+       if (flags & SP_MODE_RDONLY)
+               flags_local |= O_RDONLY;
+       if (flags & SP_MODE_NONBLOCK)
+               flags_local |= O_NONBLOCK;
+
+       if ((port->fd = open(port->name, flags_local)) < 0)
+               return SP_ERR_FAIL;
+#endif
+
+       return SP_OK;
+}
+
+/**
+ * Close the specified serial port.
+ *
+ * @param port Pointer to port structure.
+ *
+ * @return SP_OK on success, SP_ERR_FAIL on failure,
+ *         or SP_ERR_ARG if an invalid port is passed.
+ */
+int sp_close(struct sp_port *port)
+{
+       CHECK_PORT();
+
+#ifdef _WIN32
+       /* Returns non-zero upon success, 0 upon failure. */
+       if (CloseHandle(port->hdl) == 0)
+               return SP_ERR_FAIL;
+#else
+       /* Returns 0 upon success, -1 upon failure. */
+       if (close(port->fd) == -1)
+               return SP_ERR_FAIL;
+#endif
+
+       return SP_OK;
+}
+
+/**
+ * Flush serial port buffers.
+ *
+ * @param port Pointer to port structure.
+ *
+ * @return SP_OK on success, SP_ERR_FAIL on failure,
+ *         or SP_ERR_ARG if an invalid port is passed.
+ */
+int sp_flush(struct sp_port *port)
+{
+       CHECK_PORT();
+
+#ifdef _WIN32
+       /* Returns non-zero upon success, 0 upon failure. */
+       if (PurgeComm(port->hdl, PURGE_RXCLEAR | PURGE_TXCLEAR) == 0)
+               return SP_ERR_FAIL;
+#else
+       /* Returns 0 upon success, -1 upon failure. */
+       if (tcflush(port->fd, TCIOFLUSH) < 0)
+               return SP_ERR_FAIL;
+#endif
+       return SP_OK;
+}
+
+/**
+ * Write a number of bytes to the specified serial port.
+ *
+ * @param port Pointer to port structure.
+ * @param buf Buffer containing the bytes to write.
+ * @param count Number of bytes to write.
+ *
+ * @return The number of bytes written, SP_ERR_FAIL on failure,
+ *         or SP_ERR_ARG if an invalid port is passed.
+ */
+int sp_write(struct sp_port *port, const void *buf, size_t count)
+{
+       CHECK_PORT();
+
+       if (!buf)
+               return SP_ERR_ARG;
+
+#ifdef _WIN32
+       DWORD written = 0;
+       /* Returns non-zero upon success, 0 upon failure. */
+       if (WriteFile(port->hdl, buf, count, &written, NULL) == 0)
+               return SP_ERR_FAIL;
+       return written;
+#else
+       /* Returns the number of bytes written, or -1 upon failure. */
+       ssize_t written = write(port->fd, buf, count);
+       if (written < 0)
+               return SP_ERR_FAIL;
+       else
+               return written;;
+#endif
+}
+
+/**
+ * Read a number of bytes from the specified serial port.
+ *
+ * @param port Pointer to port structure.
+ * @param buf Buffer where to store the bytes that are read.
+ * @param count The number of bytes to read.
+ *
+ * @return The number of bytes read, SP_ERR_FAIL on failure,
+ *         or SP_ERR_ARG if an invalid port is passed.
+ */
+int sp_read(struct sp_port *port, void *buf, size_t count)
+{
+       CHECK_PORT();
+
+       if (!buf)
+               return SP_ERR_ARG;
+
+#ifdef _WIN32
+       DWORD bytes_read = 0;
+       /* Returns non-zero upon success, 0 upon failure. */
+       if (ReadFile(port->hdl, buf, count, &bytes_read, NULL) == 0)
+               return SP_ERR_FAIL;
+       return bytes_read;
+#else
+       ssize_t bytes_read;
+       /* Returns the number of bytes read, or -1 upon failure. */
+       if ((bytes_read = read(port->fd, buf, count)) < 0)
+               return SP_ERR_FAIL;
+       return bytes_read;
+#endif
+}
+
+/**
+ * Set serial parameters for the specified serial port.
+ *
+ * @param port Pointer to port structure.
+ * @param baudrate The baudrate to set.
+ * @param bits The number of data bits to use.
+ * @param parity The parity setting to use (0 = none, 1 = even, 2 = odd).
+ * @param stopbits The number of stop bits to use (1 or 2).
+ * @param flowcontrol The flow control settings to use (0 = none, 1 = RTS/CTS,
+ *                    2 = XON/XOFF).
+ *
+ * @return The number of bytes read, SP_ERR_FAIL on failure,
+ *         or SP_ERR_ARG if an invalid argument is passed.
+ */
+int sp_set_params(struct sp_port *port, int baudrate,
+                             int bits, int parity, int stopbits,
+                             int flowcontrol, int rts, int dtr)
+{
+       CHECK_PORT();
+
+#ifdef _WIN32
+       DCB dcb;
+
+       if (!GetCommState(port->hdl, &dcb))
+               return SP_ERR_FAIL;
+
+       switch (baudrate) {
+       /*
+        * The baudrates 50/75/134/150/200/1800/230400/460800 do not seem to
+        * have documented CBR_* macros.
+        */
+       case 110:
+               dcb.BaudRate = CBR_110;
+               break;
+       case 300:
+               dcb.BaudRate = CBR_300;
+               break;
+       case 600:
+               dcb.BaudRate = CBR_600;
+               break;
+       case 1200:
+               dcb.BaudRate = CBR_1200;
+               break;
+       case 2400:
+               dcb.BaudRate = CBR_2400;
+               break;
+       case 4800:
+               dcb.BaudRate = CBR_4800;
+               break;
+       case 9600:
+               dcb.BaudRate = CBR_9600;
+               break;
+       case 14400:
+               dcb.BaudRate = CBR_14400; /* Not available on Unix? */
+               break;
+       case 19200:
+               dcb.BaudRate = CBR_19200;
+               break;
+       case 38400:
+               dcb.BaudRate = CBR_38400;
+               break;
+       case 57600:
+               dcb.BaudRate = CBR_57600;
+               break;
+       case 115200:
+               dcb.BaudRate = CBR_115200;
+               break;
+       case 128000:
+               dcb.BaudRate = CBR_128000; /* Not available on Unix? */
+               break;
+       case 256000:
+               dcb.BaudRate = CBR_256000; /* Not available on Unix? */
+               break;
+       default:
+               return SP_ERR_ARG;
+       }
+
+       switch (stopbits) {
+       /* Note: There's also ONE5STOPBITS == 1.5 (unneeded so far). */
+       case 1:
+               dcb.StopBits = ONESTOPBIT;
+               break;
+       case 2:
+               dcb.StopBits = TWOSTOPBITS;
+               break;
+       default:
+               return SP_ERR_ARG;
+       }
+
+       switch (parity) {
+       /* Note: There's also SPACEPARITY, MARKPARITY (unneeded so far). */
+       case SP_PARITY_NONE:
+               dcb.Parity = NOPARITY;
+               break;
+       case SP_PARITY_EVEN:
+               dcb.Parity = EVENPARITY;
+               break;
+       case SP_PARITY_ODD:
+               dcb.Parity = ODDPARITY;
+               break;
+       default:
+               return SP_ERR_ARG;
+       }
+
+       if (rts != -1) {
+               if (rts)
+                       dcb.fRtsControl = RTS_CONTROL_ENABLE;
+               else
+                       dcb.fRtsControl = RTS_CONTROL_DISABLE;
+       }
+
+       if (dtr != -1) {
+               if (dtr)
+                       dcb.fDtrControl = DTR_CONTROL_ENABLE;
+               else
+                       dcb.fDtrControl = DTR_CONTROL_DISABLE;
+       }
+
+       if (!SetCommState(port->hdl, &dcb))
+               return SP_ERR_FAIL;
+#else
+       struct termios term;
+       speed_t baud;
+       int controlbits;
+
+       if (tcgetattr(port->fd, &term) < 0)
+               return SP_ERR_FAIL;
+
+       switch (baudrate) {
+       case 50:
+               baud = B50;
+               break;
+       case 75:
+               baud = B75;
+               break;
+       case 110:
+               baud = B110;
+               break;
+       case 134:
+               baud = B134;
+               break;
+       case 150:
+               baud = B150;
+               break;
+       case 200:
+               baud = B200;
+               break;
+       case 300:
+               baud = B300;
+               break;
+       case 600:
+               baud = B600;
+               break;
+       case 1200:
+               baud = B1200;
+               break;
+       case 1800:
+               baud = B1800;
+               break;
+       case 2400:
+               baud = B2400;
+               break;
+       case 4800:
+               baud = B4800;
+               break;
+       case 9600:
+               baud = B9600;
+               break;
+       case 19200:
+               baud = B19200;
+               break;
+       case 38400:
+               baud = B38400;
+               break;
+       case 57600:
+               baud = B57600;
+               break;
+       case 115200:
+               baud = B115200;
+               break;
+       case 230400:
+               baud = B230400;
+               break;
+#if !defined(__APPLE__) && !defined(__OpenBSD__)
+       case 460800:
+               baud = B460800;
+               break;
+#endif
+       default:
+               return SP_ERR_ARG;
+       }
+
+       if (cfsetospeed(&term, baud) < 0)
+               return SP_ERR_FAIL;
+
+       if (cfsetispeed(&term, baud) < 0)
+               return SP_ERR_FAIL;
+
+       term.c_cflag &= ~CSIZE;
+       switch (bits) {
+       case 8:
+               term.c_cflag |= CS8;
+               break;
+       case 7:
+               term.c_cflag |= CS7;
+               break;
+       default:
+               return SP_ERR_ARG;
+       }
+
+       term.c_cflag &= ~CSTOPB;
+       switch (stopbits) {
+       case 1:
+               term.c_cflag &= ~CSTOPB;
+               break;
+       case 2:
+               term.c_cflag |= CSTOPB;
+               break;
+       default:
+               return SP_ERR_ARG;
+       }
+
+       term.c_iflag &= ~(IXON | IXOFF);
+       term.c_cflag &= ~CRTSCTS;
+       switch (flowcontrol) {
+       case 0:
+               /* No flow control. */
+               break;
+       case 1:
+               term.c_cflag |= CRTSCTS;
+               break;
+       case 2:
+               term.c_iflag |= IXON | IXOFF;
+               break;
+       default:
+               return SP_ERR_ARG;
+       }
+
+       term.c_iflag &= ~IGNPAR;
+       term.c_cflag &= ~(PARODD | PARENB);
+       switch (parity) {
+       case SP_PARITY_NONE:
+               term.c_iflag |= IGNPAR;
+               break;
+       case SP_PARITY_EVEN:
+               term.c_cflag |= PARENB;
+               break;
+       case SP_PARITY_ODD:
+               term.c_cflag |= PARENB | PARODD;
+               break;
+       default:
+               return SP_ERR_ARG;
+       }
+
+       /* Turn off all serial port cooking. */
+       term.c_iflag &= ~(ISTRIP | INLCR | ICRNL);
+       term.c_oflag &= ~(ONLCR | OCRNL | ONOCR);
+#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
+       term.c_oflag &= ~OFILL;
+#endif
+
+       /* Disable canonical mode, and don't echo input characters. */
+       term.c_lflag &= ~(ICANON | ECHO);
+
+       /* Write the configured settings. */
+       if (tcsetattr(port->fd, TCSADRAIN, &term) < 0)
+               return SP_ERR_FAIL;
+
+       if (rts != -1) {
+               controlbits = TIOCM_RTS;
+               if (ioctl(port->fd, rts ? TIOCMBIS : TIOCMBIC,
+                               &controlbits) < 0)
+                       return SP_ERR_FAIL;
+       }
+
+       if (dtr != -1) {
+               controlbits = TIOCM_DTR;
+               if (ioctl(port->fd, dtr ? TIOCMBIS : TIOCMBIC,
+                               &controlbits) < 0)
+                       return SP_ERR_FAIL;
+       }
+#endif
+
+       return SP_OK;
+}
+
+/**
+ * Get error code for failed operation.
+ *
+ * In order to obtain the correct result, this function should be called
+ * straight after the failure, before executing any other system operations.
+ *
+ * @return The system's numeric code for the error that caused the last
+ *         operation to fail.
+ */
+int sp_last_error_code(void)
+{
+#ifdef _WIN32
+       return GetLastError();
+#else
+       return errno;
+#endif
+}
+
+/**
+ * Get error message for failed operation.
+ *
+ * In order to obtain the correct result, this function should be called
+ * straight after the failure, before executing other system operations.
+ *
+ * @return The system's message for the error that caused the last
+ *         operation to fail. This string may be allocated by the function,
+ *         and can be freed after use by calling sp_free_error_message.
+ */
+char *sp_last_error_message(void)
+{
+#ifdef _WIN32
+       LPVOID message;
+       DWORD error = GetLastError();
+
+       FormatMessage(
+               FORMAT_MESSAGE_ALLOCATE_BUFFER |
+               FORMAT_MESSAGE_FROM_SYSTEM |
+               FORMAT_MESSAGE_IGNORE_INSERTS,
+               NULL,
+               error,
+               MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+               (LPTSTR) &message,
+               0, NULL );
+
+       return message;
+#else
+       return strerror(errno);
+#endif
+}
+
+/**
+ * Free error message.
+ *
+ * This function can be used to free a string returned by the
+ * sp_last_error_message function.
+ */
+void sp_free_error_message(char *message)
+{
+#ifdef _WIN32
+       LocalFree(message);
+#endif
+}
diff --git a/serialport.h b/serialport.h
new file mode 100644 (file)
index 0000000..dc3e22d
--- /dev/null
@@ -0,0 +1,76 @@
+/*
+ * This file is part of the libserialport project.
+ *
+ * Copyright (C) 2013 Martin Ling <martin-libserialport@earth.li>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stddef.h>
+#ifdef _WIN32
+#include <windows.h>
+#endif
+
+/* A serial port. */
+struct sp_port {
+       /* Name used to open the port */
+       char *name;
+       /* OS-specific port handle */
+#ifdef _WIN32
+       HANDLE hdl;
+#else
+       int fd;
+#endif
+};
+
+/* Return values. */
+enum {
+       /* Operation completed successfully. */
+       SP_OK = 0,
+       /* A system error occured while executing the operation. */
+       SP_ERR_FAIL = -1,
+       /* Invalid arguments were passed to the function. */
+       SP_ERR_ARG = -2
+};
+
+/* Port access modes. */
+enum {
+       /* Open port for read/write access. */
+       SP_MODE_RDWR = 1,
+       /* Open port for read access only. */
+       SP_MODE_RDONLY = 2,
+       /* Open port in non-blocking mode. */
+       SP_MODE_NONBLOCK = 4
+};
+
+/* Parity settings. */
+enum {
+       /* No parity. */
+       SP_PARITY_NONE = 0,
+       /* Even parity. */
+       SP_PARITY_EVEN = 1,
+       /* Odd parity. */
+       SP_PARITY_ODD = 2
+};
+
+int sp_open(struct sp_port *port, char *portname, int flags);
+int sp_close(struct sp_port *port);
+int sp_flush(struct sp_port *port);
+int sp_write(struct sp_port *port, const void *buf, size_t count);
+int sp_read(struct sp_port *port, void *buf, size_t count);
+int sp_set_params(struct sp_port *port, int baudrate, int bits, int parity,
+               int stopbits, int flowcontrol, int rts, int dtr);
+int sp_last_error_code(void);
+char *sp_last_error_message(void);
+void sp_free_error_message(char *message);