From 65540b205445edffe8ca75e7d797ea2f3d9ab41d Mon Sep 17 00:00:00 2001 From: reinelt <> Date: Fri, 7 Apr 2000 05:42:20 +0000 Subject: [lcd4linux @ 2000-04-07 05:42:20 by reinelt] UUCP style lockfiles for the serial port --- Makefile.am | 1 + Makefile.in | 12 ++--- MatrixOrbital.c | 34 ++++++++++-- lcd4linux.c | 40 +++++++++++--- lock.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ lock.h | 37 +++++++++++++ 6 files changed, 266 insertions(+), 17 deletions(-) create mode 100644 lock.c create mode 100644 lock.h diff --git a/Makefile.am b/Makefile.am index 1889b16..62d720e 100644 --- a/Makefile.am +++ b/Makefile.am @@ -14,6 +14,7 @@ endif lcd4linux_SOURCES = \ lcd4linux.c \ cfg.c cfg.h \ +lock.c lock.h \ parser.c parser.h \ processor.c processor.h \ system.c system.h \ diff --git a/Makefile.in b/Makefile.in index ccdca34..722390e 100644 --- a/Makefile.in +++ b/Makefile.in @@ -73,7 +73,7 @@ AM_CFLAGS = $(X_CFLAGS) -Wall lcd4linux_LDFLAGS = $(X_LIBS) @WITH_X_TRUE@lcd4linux_LDADD = -lX11 -lcd4linux_SOURCES = lcd4linux.c cfg.c cfg.h parser.c parser.h processor.c processor.h system.c system.h isdn.c isdn.h filter.c filter.h display.c display.h pixmap.c pixmap.h fontmap.c fontmap.h Skeleton.c MatrixOrbital.c Raster.c XWindow.c +lcd4linux_SOURCES = lcd4linux.c cfg.c cfg.h lock.c lock.h parser.c parser.h processor.c processor.h system.c system.h isdn.c isdn.h filter.c filter.h display.c display.h pixmap.c pixmap.h fontmap.c fontmap.h Skeleton.c MatrixOrbital.c Raster.c XWindow.c ACLOCAL_M4 = $(top_srcdir)/aclocal.m4 mkinstalldirs = $(SHELL) $(top_srcdir)/mkinstalldirs @@ -89,9 +89,9 @@ X_CFLAGS = @X_CFLAGS@ X_LIBS = @X_LIBS@ X_EXTRA_LIBS = @X_EXTRA_LIBS@ X_PRE_LIBS = @X_PRE_LIBS@ -lcd4linux_OBJECTS = lcd4linux.o cfg.o parser.o processor.o system.o \ -isdn.o filter.o display.o pixmap.o fontmap.o Skeleton.o MatrixOrbital.o \ -Raster.o XWindow.o +lcd4linux_OBJECTS = lcd4linux.o cfg.o lock.o parser.o processor.o \ +system.o isdn.o filter.o display.o pixmap.o fontmap.o Skeleton.o \ +MatrixOrbital.o Raster.o XWindow.o @WITH_X_TRUE@lcd4linux_DEPENDENCIES = CFLAGS = @CFLAGS@ COMPILE = $(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) @@ -107,8 +107,8 @@ TAR = tar GZIP_ENV = --best DEP_FILES = .deps/MatrixOrbital.P .deps/Raster.P .deps/Skeleton.P \ .deps/XWindow.P .deps/cfg.P .deps/display.P .deps/filter.P \ -.deps/fontmap.P .deps/isdn.P .deps/lcd4linux.P .deps/parser.P \ -.deps/pixmap.P .deps/processor.P .deps/system.P +.deps/fontmap.P .deps/isdn.P .deps/lcd4linux.P .deps/lock.P \ +.deps/parser.P .deps/pixmap.P .deps/processor.P .deps/system.P SOURCES = $(lcd4linux_SOURCES) OBJECTS = $(lcd4linux_OBJECTS) diff --git a/MatrixOrbital.c b/MatrixOrbital.c index 833c794..fd77b85 100644 --- a/MatrixOrbital.c +++ b/MatrixOrbital.c @@ -1,4 +1,4 @@ -/* $Id: MatrixOrbital.c,v 1.12 2000/03/26 18:46:28 reinelt Exp $ +/* $Id: MatrixOrbital.c,v 1.13 2000/04/07 05:42:20 reinelt Exp $ * * driver for Matrix Orbital serial display modules * @@ -20,6 +20,10 @@ * * * $Log: MatrixOrbital.c,v $ + * Revision 1.13 2000/04/07 05:42:20 reinelt + * + * UUCP style lockfiles for the serial port + * * Revision 1.12 2000/03/26 18:46:28 reinelt * * bug in pixmap.c that leaded to empty bars fixed @@ -76,13 +80,15 @@ #include #include +#include +#include #include +#include #include #include -#include -#include #include "cfg.h" +#include "lock.h" #include "display.h" #define SPEED 19200 @@ -122,8 +128,16 @@ static SEGMENT Segment[128] = {{ len1:0, len2:0, type:255, used:0, ascii:32 static int MO_open (void) { int fd; + pid_t pid; struct termios portset; + if ((pid=lock_port(Port))!=0) { + if (pid==-1) + fprintf (stderr, "MatrixOrbital: port %s could not be locked\n", Port); + else + fprintf (stderr, "MatrixOrbital: port %s is locked by process %d\n", Port, pid); + return -1; + } fd = open(Port, O_RDWR | O_NOCTTY | O_NDELAY); if (fd==-1) { fprintf (stderr, "MatrixOrbital: open(%s) failed: %s\n", Port, strerror(errno)); @@ -349,6 +363,8 @@ int MO_clear (void) return 0; } +static void MO_quit (int signal); //forward decvlaration + int MO_init (LCD *Self) { char *port; @@ -391,6 +407,10 @@ int MO_init (LCD *Self) Device=MO_open(); if (Device==-1) return -1; + signal(SIGINT, MO_quit); + signal(SIGQUIT, MO_quit); + signal(SIGTERM, MO_quit); + MO_clear(); MO_contrast(); @@ -522,6 +542,14 @@ int MO_flush (void) return 0; } +static void MO_quit (int signal) +{ + MO_clear(); + MO_flush(); + close (Device); + unlock_port(Port); + exit (0); +} LCD MatrixOrbital[] = { { "LCD0821", 2, 8, XRES, YRES, BARS, MO_init, MO_clear, MO_put, MO_bar, MO_flush }, diff --git a/lcd4linux.c b/lcd4linux.c index 974f8eb..6963609 100644 --- a/lcd4linux.c +++ b/lcd4linux.c @@ -1,4 +1,4 @@ -/* $Id: lcd4linux.c,v 1.17 2000/04/03 17:31:52 reinelt Exp $ +/* $Id: lcd4linux.c,v 1.18 2000/04/07 05:42:20 reinelt Exp $ * * LCD4Linux * @@ -20,6 +20,10 @@ * * * $Log: lcd4linux.c,v $ + * Revision 1.18 2000/04/07 05:42:20 reinelt + * + * UUCP style lockfiles for the serial port + * * Revision 1.17 2000/04/03 17:31:52 reinelt * * suppress welcome message if display is smaller than 20x2 @@ -120,11 +124,35 @@ static void usage(void) printf ("usage: lcd4linux [-h] [-l] [-c key=value] [-f config-file] [-o output-file]\n"); } +static int hello (void) +{ + int x, y; + + lcd_query (&y, &x, NULL, NULL, NULL); + + if (x>=20) { + lcd_put (1, 1, "* LCD4Linux V" VERSION " *"); + lcd_put (2, 1, " (c) 2000 M.Reinelt"); + } else if (x >=16) { + lcd_put (1, 1, "LCD4Linux " VERSION); + lcd_put (2, 1, "(c) M.Reinelt"); + } else if (x >=9) { + lcd_put (1, 1, "LCD4Linux"); + } else if (x>=7) { + lcd_put (1, 1, "L4Linux"); + } else return 0; + + lcd_put (1, 1, "* LCD4Linux V" VERSION " *"); + lcd_put (2, 1, " (c) 2000 M.Reinelt"); + lcd_flush(); + return 1; +} + int main (int argc, char *argv[]) { char *cfg="/etc/lcd4linux.conf"; char *driver; - int c, x, y, smooth; + int c, smooth; while ((c=getopt (argc, argv, "c:f:hlo:"))!=EOF) { switch (c) { @@ -182,15 +210,11 @@ int main (int argc, char *argv[]) process_init(); lcd_clear(); - lcd_query (&y, &x, NULL, NULL, NULL); - if (x>=20 && y>=2) { - lcd_put (1, 1, "* LCD4Linux V" VERSION " *"); - lcd_put (2, 1, " (c) 2000 M.Reinelt"); - lcd_flush(); + if (hello()) { sleep (3); lcd_clear(); } - + smooth=0; while (1) { process (smooth); diff --git a/lock.c b/lock.c new file mode 100644 index 0000000..dc83a10 --- /dev/null +++ b/lock.c @@ -0,0 +1,159 @@ +/* $Id: lock.c,v 1.1 2000/04/07 05:42:20 reinelt Exp $ + * + * UUCP style locking + * + * Copyright 1999, 2000 by Michael Reinelt (reinelt@eunet.at) + * + * This program 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. + * + * 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 General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * + * $Log: lock.c,v $ + * Revision 1.1 2000/04/07 05:42:20 reinelt + * + * UUCP style lockfiles for the serial port + * + */ + +/* + * exported functions: + * + * pid_t lock_port (char *port) + * returns 0 if port could be successfully locked + * otherwise returns PID of the process holding the lock + * + * pid_t unlock_port (char *port) + * returns 0 if port could be successfully unlocked + * otherwise returns PID of the process holding the lock + * + */ + + +#include +#include +#include +#include +#include +#include +#include +#include +#include + + +#include "lock.h" + + +pid_t lock_port (char *port) +{ + char lockfile[256]; + char tempfile[256]; + char buffer[16]; + char *p; + int fd, len, pid; + + if ((p=strrchr (port, '/'))==NULL) + p=port; + else + p++; + + snprintf(lockfile, sizeof(lockfile), LOCK, p); + snprintf(tempfile, sizeof(tempfile), LOCK, "TMP.XXXXXX"); + + if (mktemp(tempfile)==NULL) { + fprintf(stderr, "mktemp(%s) failed.\n", tempfile); + return -1; + } + + if ((fd=creat(tempfile, 0664))==-1) { + fprintf(stderr, "creat(%s) failed: %s\n", tempfile, strerror(errno)); + return -1; + } + + snprintf (buffer, sizeof(buffer), "%10d\n", (int)getpid()); + if (write(fd, buffer, strlen(buffer))!=strlen(buffer)) { + fprintf(stderr, "write(%s) failed: %s\n", tempfile, strerror(errno)); + close(fd); + unlink(tempfile); + return -1; + } + close (fd); + + + while (link(tempfile, lockfile)==-1) { + + if (errno!=EEXIST) { + fprintf(stderr, "link(%s, %s) failed: %s\n", tempfile, lockfile, strerror(errno)); + unlink(tempfile); + return -1; + } + + if ((fd=open(lockfile, O_RDONLY))==-1) { + if (errno==ENOENT) continue; // lockfile disappared + fprintf (stderr, "open(%s) failed: %s\n", lockfile, strerror(errno)); + unlink (tempfile); + return -1; + } + + len=read(fd, buffer, sizeof(buffer)-1); + if (len<0) { + fprintf (stderr, "read(%s) failed: %s\n", lockfile, strerror(errno)); + unlink (tempfile); + return -1; + } + + buffer[len]='\0'; + if (sscanf(buffer, "%d", &pid)!=1 || pid==0) { + fprintf (stderr, "scan(%s) failed.\n", lockfile); + unlink (tempfile); + return -1; + } + + if (pid==getpid()) { + fprintf (stderr, "%s already locked by us. uh-oh...\n", lockfile); + unlink(tempfile); + return 0; + } + + if ((kill(pid, 0)==-1) && errno==ESRCH) { + fprintf (stderr, "removing stale lockfile %s\n", lockfile); + if (unlink(lockfile)==-1 && errno!=ENOENT) { + fprintf (stderr, "unlink(%s) failed: %s\n", lockfile, strerror(errno)); + unlink(tempfile); + return pid; + } + continue; + } + unlink (tempfile); + return pid; + } + + unlink (tempfile); + return 0; +} + + +pid_t unlock_port (char *port) +{ + char lockfile[256]; + char *p; + + if ((p=strrchr (port, '/'))==NULL) + p=port; + else + p++; + + snprintf(lockfile, sizeof(lockfile), LOCK, p); + unlink (lockfile); + return 0; +} diff --git a/lock.h b/lock.h new file mode 100644 index 0000000..649cbfe --- /dev/null +++ b/lock.h @@ -0,0 +1,37 @@ +/* $Id: lock.h,v 1.1 2000/04/07 05:42:20 reinelt Exp $ + * + * UUCP style port locking + * + * Copyright 1999, 2000 by Michael Reinelt (reinelt@eunet.at) + * + * This program 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. + * + * 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 General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * + * $Log: lock.h,v $ + * Revision 1.1 2000/04/07 05:42:20 reinelt + * + * UUCP style lockfiles for the serial port + * + */ + +#ifndef _LOCK_H_ +#define _LOCK_H_ + +#define LOCK "/var/lock/LCK..%s" + +pid_t lock_port (char *port); +pid_t unlock_port (char *port); + +#endif -- cgit v1.2.3