/* $Id: drv_generic_serial.c,v 1.17 2005/05/08 04:32:44 reinelt Exp $
*
* generic driver helper for serial and usbserial displays
*
* Copyright (C) 1999, 2000 Michael Reinelt <reinelt@eunet.at>
* Copyright (C) 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
*
* This file is part of LCD4Linux.
*
* LCD4Linux is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* LCD4Linux 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 General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*
* $Log: drv_generic_serial.c,v $
* Revision 1.17 2005/05/08 04:32:44 reinelt
* CodingStyle added and applied
*
* Revision 1.16 2005/01/18 06:30:23 reinelt
* added (C) to all copyright statements
*
* Revision 1.15 2004/06/26 12:04:59 reinelt
*
* uh-oh... the last CVS log message messed up things a lot...
*
* Revision 1.14 2004/06/26 09:27:21 reinelt
*
* added '-W' to CFLAGS
* changed all C++ comments to C ones
* cleaned up a lot of signed/unsigned mistakes
*
* Revision 1.13 2004/06/26 06:12:15 reinelt
*
* support for Beckmann+Egle Compact Terminals
* some mostly cosmetic changes in the MatrixOrbital and USBLCD driver
* added debugging to the generic serial driver
* fixed a bug in the generic text driver where icons could be drawn outside
* the display bounds
*
* Revision 1.12 2004/06/20 10:09:55 reinelt
*
* 'const'ified the whole source
*
* Revision 1.11 2004/06/01 06:45:30 reinelt
*
* some Fixme's processed
* documented some code
*
* Revision 1.10 2004/05/31 21:05:13 reinelt
*
* fixed lots of bugs in the Cwlinux driver
* do not emit EAGAIN error on the first retry
* made plugin_i2c_sensors a bit less 'chatty'
* moved init and exit functions to the bottom of plugin_pop3
*
* Revision 1.9 2004/05/28 13:51:42 reinelt
*
* ported driver for Beckmann+Egle Mini-Terminals
* added 'flags' parameter to serial_init()
*
* Revision 1.8 2004/03/03 04:44:16 reinelt
* changes (cosmetics?) to the big patch from Martin
* hash patch un-applied
*
* Revision 1.7 2004/03/03 03:47:04 reinelt
* big patch from Martin Hejl:
* - use qprintf() where appropriate
* - save CPU cycles on gettimeofday()
* - add quit() functions to free allocated memory
* - fixed lots of memory leaks
*
* Revision 1.6 2004/02/14 11:56:17 reinelt
* M50530 driver ported
* changed lots of 'char' to 'unsigned char'
*
* Revision 1.5 2004/02/04 19:10:51 reinelt
* Crystalfontz driver nearly finished
*
* Revision 1.4 2004/02/01 08:05:12 reinelt
* Crystalfontz 633 extensions (CRC checking and stuff)
* Models table for HD44780
* Noritake VFD BVrightness patch from Bill Paxton
*
* Revision 1.3 2004/01/29 04:40:02 reinelt
* every .c file includes "config.h" now
*
* Revision 1.2 2004/01/25 05:30:09 reinelt
* plugin_netdev for parsing /proc/net/dev added
*
* Revision 1.1 2004/01/20 14:26:09 reinelt
* moved drv_generic to drv_generic_serial
*
* Revision 1.2 2004/01/20 05:36:59 reinelt
* moved text-display-specific stuff to drv_generic_text
* moved all the bar stuff from drv_generic_bar to generic_text
*
* Revision 1.1 2004/01/20 04:51:39 reinelt
* moved generic stuff from drv_MatrixOrbital to drv_generic
* implemented new-stylish bars which are nearly finished
*
*/
/*
*
* exported fuctions:
*
* int drv_generic_serial_open (char *section, char *driver, unsigned int flags)
* opens the serial port
*
* int drv_generic_serial_poll (char *string, int len)
* reads from the serial or USB port
* without retry
*
* int drv_generic_serial_read (char *string, int len);
* reads from the serial or USB port
* with retry
*
* void drv_generic_serial_write (char *string, int len);
* writes to the serial or USB port
*
* int drv_generic_serial_close (void);
* closes the serial port
*
*/
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <termios.h>
#include <fcntl.h>
#include <time.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "debug.h"
#include "qprintf.h"
#include "cfg.h"
#include "drv_generic_serial.h"
static char *Section;
static char *Driver;
static char *Port;
static speed_t Speed;
static int Device = -1;
#define LOCK "/var/lock/LCK..%s"
/****************************************/
/*** generic serial/USB communication ***/
/****************************************/
static pid_t drv_generic_serial_lock_port(const char *Port)
{
char lockfile[256];
char tempfile[256];
char buffer[16];
char *port, *p;
int fd, len, pid;
if (strncmp(Port, "/dev/", 5) == 0) {
port = strdup(Port + 5);
} else {
port = strdup(Port);
}
while ((p = strchr(port, '/')) != NULL) {
*p = '_';
}
qprintf(lockfile, sizeof(lockfile), LOCK, port);
qprintf(tempfile, sizeof(tempfile), LOCK, "TMP.XXXXXX");
free(port);
if ((fd = mkstemp(tempfile)) == -1) {
error("mkstemp(%s) failed: %s", tempfile, strerror(errno));
return -1;
}
if (fchmod(fd, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH) == -1) {
error("fchmod(%s) failed: %s", tempfile, strerror(errno));
close(fd);
unlink(tempfile);
return -1;
}
snprintf(buffer, sizeof(buffer), "%10d\n", (int) getpid());
len = strlen(buffer);
if (write(fd, buffer, len) != len) {
error("write(%s) failed: %s", tempfile, strerror(errno));
close(fd);
unlink(tempfile);
return -1;
}
close(fd);
while (link(tempfile, lockfile) == -1) {
if (errno != EEXIST) {
error("link(%s, %s) failed: %s", tempfile, lockfile, strerror(errno));
unlink(tempfile);
return -1;
}
if ((fd = open(lockfile, O_RDONLY)) == -1) {
if (errno == ENOENT)
continue; /* lockfile disappared */
error("open(%s) failed: %s", lockfile, strerror(errno));
unlink(tempfile);
return -1;
}
len = read(fd, buffer, sizeof(buffer) - 1);
if (len < 0) {
error("read(%s) failed: %s", lockfile, strerror(errno));
unlink(tempfile);
return -1;
}
buffer[len] = '\0';
if (sscanf(buffer, "%d", &pid) != 1 || pid == 0) {
error("scan(%s) failed.", lockfile);
unlink(tempfile);
return -1;
}
if (pid == getpid()) {
error("%s already locked by us. uh-oh...", lockfile);
unlink(tempfile);
return 0;
}
if ((kill(pid, 0) == -1) && errno == ESRCH) {
error("removing stale lockfile %s", lockfile);
if (unlink(lockfile) == -1 && errno != ENOENT) {
error("unlink(%s) failed: %s", lockfile, strerror(errno));
unlink(tempfile);
return pid;
}
continue;
}
unlink(tempfile);
return pid;
}
unlink(tempfile);
return 0;
}
static pid_t drv_generic_serial_unlock_port(const char *Port)
{
char lockfile[256];
char *port, *p;
if (strncmp(Port, "/dev/", 5) == 0) {
port = strdup(Port + 5);
} else {
port = strdup(Port);
}
while ((p = strchr(port, '/')) != NULL) {
*p = '_';
}
qprintf(lockfile, sizeof(lockfile), LOCK, port);
unlink(lockfile);
free(port);
return 0;
}
int drv_generic_serial_open(const char *section, const char *driver, const unsigned int flags)
{
int i, fd;
pid_t pid;
struct termios portset;
Section = (char *) section;
Driver = (char *) driver;
Port = cfg_get(section, "Port", NULL);
if (Port == NULL || *Port == '\0') {
error("%s: no '%s.Port' entry from %s", Driver, section, cfg_source());
return -1;
}
if (cfg_number(section, "Speed", 19200, 1200, 115200, &i) < 0)
return -1;
switch (i) {
case 1200:
Speed = B1200;
break;
case 2400:
Speed = B2400;
break;
case 4800:
Speed = B4800;
break;
case 9600:
Speed = B9600;
break;
case 19200:
Speed = B19200;
break;
case 38400:
Speed = B38400;
break;
case 57600:
Speed = B57600;
break;
case 115200:
Speed = B115200;
break;
default:
error("%s: unsupported speed '%d' from %s", Driver, i, cfg_source());
return -1;
}
info("%s: using port '%s' at %d baud", Driver, Port, i);
if ((pid = drv_generic_serial_lock_port(Port)) != 0) {
if (pid == -1)
error("%s: port %s could not be locked", Driver, Port);
else
error("%s: port %s is locked by process %d", Driver, Port, pid);
return -1;
}
fd = open(Port, O_RDWR | O_NOCTTY | O_NDELAY);
if (fd == -1) {
error("%s: open(%s) failed: %s", Driver, Port, strerror(errno));
drv_generic_serial_unlock_port(Port);
return -1;
}
if (tcgetattr(fd, &portset) == -1) {
error("%s: tcgetattr(%s) failed: %s", Driver, Port, strerror(errno));
drv_generic_serial_unlock_port(Port);
return -1;
}
cfmakeraw(&portset);
portset.c_cflag |= flags;
cfsetispeed(&portset, Speed);
cfsetospeed(&portset, Speed);
if (tcsetattr(fd, TCSANOW, &portset) == -1) {
error("%s: tcsetattr(%s) failed: %s", Driver, Port, strerror(errno));
drv_generic_serial_unlock_port(Port);
return -1;
}
Device = fd;
return Device;
}
int drv_generic_serial_poll(char *string, const int len)
{
int ret;
if (Device == -1)
return -1;
ret = read(Device, string, len);
if (ret < 0 && errno != EAGAIN) {
error("%s: read(%s) failed: %s", Driver, Port, strerror(errno));
}
return ret;
}
int drv_generic_serial_read(char *string, const int len)
{
int count, run, ret;
count = len < 0 ? -len : len;
for (run = 0; run < 10; run++) {
ret = drv_generic_serial_poll(string, count);
if (ret >= 0 || errno != EAGAIN)
break;
info("%s: read(%s): EAGAIN", Driver, Port);
usleep(1000);
}
if (ret > 0 && ret != count && len > 0) {
error("%s: partial read(%s): len=%d ret=%d", Driver, Port, len, ret);
}
return ret;
}
void drv_generic_serial_write(const char *string, const int len)
{
int run, ret;
#if 0
int i;
for (i = 0; i < len; i++) {
int c = string[i];
debug("serial_write: %03d %03o 0x%02x %c", c, c, c, iscntrl(c) ? '*' : c);
}
#endif
if (Device == -1)
return;
for (run = 0; run < 10; run++) {
ret = write(Device, string, len);
if (ret >= 0 || errno != EAGAIN)
break;
if (run > 0)
info("%s: write(%s): EAGAIN #%d", Driver, Port, run);
usleep(1000);
}
if (ret < 0) {
error("%s: write(%s) failed: %s", Driver, Port, strerror(errno));
} else if (ret != len) {
error("%s: partial write(%s): len=%d ret=%d", Driver, Port, len, ret);
}
return;
}
int drv_generic_serial_close(void)
{
info("%s: closing port %s", Driver, Port);
close(Device);
drv_generic_serial_unlock_port(Port);
free(Port);
return 0;
}