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authorJörg Frings-Fürst <debian@jff-webhosting.net>2014-12-02 20:17:04 +0100
committerJörg Frings-Fürst <debian@jff-webhosting.net>2014-12-02 20:17:04 +0100
commit7d8191b83e163d76bb05e13b373638e4eeb7da95 (patch)
treefe29c36a3cb4ef2267b2253da4dde8ce360b3cb5 /sanei/sanei_thread.c
Initial import of sane-frontends version 1.0.14-9
Diffstat (limited to 'sanei/sanei_thread.c')
-rw-r--r--sanei/sanei_thread.c425
1 files changed, 425 insertions, 0 deletions
diff --git a/sanei/sanei_thread.c b/sanei/sanei_thread.c
new file mode 100644
index 0000000..0c95fdb
--- /dev/null
+++ b/sanei/sanei_thread.c
@@ -0,0 +1,425 @@
+/* sane - Scanner Access Now Easy.
+ Copyright (C) 1998-2001 Yuri Dario
+ Copyright (C) 2003-2004 Gerhard Jaeger (pthread/process support)
+ This file is part of the SANE package.
+
+ 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 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 General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ MA 02111-1307, USA.
+
+ As a special exception, the authors of SANE give permission for
+ additional uses of the libraries contained in this release of SANE.
+
+ The exception is that, if you link a SANE library with other files
+ to produce an executable, this does not by itself cause the
+ resulting executable to be covered by the GNU General Public
+ License. Your use of that executable is in no way restricted on
+ account of linking the SANE library code into it.
+
+ This exception does not, however, invalidate any other reasons why
+ the executable file might be covered by the GNU General Public
+ License.
+
+ If you submit changes to SANE to the maintainers to be included in
+ a subsequent release, you agree by submitting the changes that
+ those changes may be distributed with this exception intact.
+
+ If you write modifications of your own for SANE, it is your choice
+ whether to permit this exception to apply to your modifications.
+ If you do not wish that, delete this exception notice.
+
+ OS/2
+ Helper functions for the OS/2 port (using threads instead of forked
+ processes). Don't use them in the backends, they are used automatically by
+ macros.
+
+ Other OS:
+ use this lib, if you intend to let run your reader function within its own
+ task (thread or process). Depending on the OS and/or the configure settings
+ pthread or fork is used to achieve this goal.
+*/
+
+#include "sane/config.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <signal.h>
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+#ifdef HAVE_OS2_H
+# define INCL_DOSPROCESS
+# include <os2.h>
+#endif
+#if !defined USE_PTHREAD && !defined HAVE_OS2_H
+# include <sys/wait.h>
+#endif
+#if defined USE_PTHREAD
+# include <pthread.h>
+#endif
+
+#define BACKEND_NAME sanei_thread /**< name of this module for debugging */
+
+#include <sane/sane.h>
+#include "../include/sane/sanei_debug.h"
+#include "../include/sane/sanei_thread.h"
+
+#ifndef _VAR_NOT_USED
+# define _VAR_NOT_USED(x) ((x)=(x))
+#endif
+
+typedef struct {
+
+ int (*func)( void* );
+ SANE_Status status;
+ void *func_data;
+
+} ThreadDataDef, *pThreadDataDef;
+
+static ThreadDataDef td;
+
+/** for init issues - here only for the debug output
+ */
+void
+sanei_thread_init( void )
+{
+ DBG_INIT();
+
+ memset( &td, 0, sizeof(ThreadDataDef));
+ td.status = SANE_STATUS_GOOD;
+}
+
+SANE_Bool
+sanei_thread_is_forked( void )
+{
+#if defined USE_PTHREAD || defined HAVE_OS2_H
+ return SANE_FALSE;
+#else
+ return SANE_TRUE;
+#endif
+}
+
+int
+sanei_thread_kill( int pid )
+{
+ DBG(2, "sanei_thread_kill() will kill %d\n", (int)pid);
+#ifdef USE_PTHREAD
+#if defined (__APPLE__) && defined (__MACH__)
+ return pthread_kill((pthread_t)pid, SIGUSR2);
+#else
+ return pthread_cancel((pthread_t)pid);
+#endif
+#elif defined HAVE_OS2_H
+ return DosKillThread(pid);
+#else
+ return kill( pid, SIGTERM );
+#endif
+}
+
+#ifdef HAVE_OS2_H
+
+static void
+local_thread( void *arg )
+{
+ pThreadDataDef ltd = (pThreadDataDef)arg;
+
+ DBG( 2, "thread started, calling func() now...\n" );
+ ltd->status = ltd->func( ltd->func_data );
+
+ DBG( 2, "func() done - status = %d\n", ltd->status );
+ _endthread();
+}
+
+/*
+ * starts a new thread or process
+ * parameters:
+ * star address of reader function
+ * args pointer to scanner data structure
+ *
+ */
+int
+sanei_thread_begin( int (*func)(void *args), void* args )
+{
+ int pid;
+
+ td.func = func;
+ td.func_data = args;
+
+ pid = _beginthread( local_thread, NULL, 1024*1024, (void*)&td );
+ if ( pid == -1 ) {
+ DBG( 1, "_beginthread() failed\n" );
+ return -1;
+ }
+
+ DBG( 2, "_beginthread() created thread %d\n", pid );
+ return pid;
+}
+
+int
+sanei_thread_waitpid( int pid, int *status )
+{
+ if (status)
+ *status = 0;
+ return pid; /* DosWaitThread( (TID*) &pid, DCWW_WAIT);*/
+}
+
+int
+sanei_thread_sendsig( int pid, int sig )
+{
+ return 0;
+}
+
+#else /* HAVE_OS2_H */
+
+#ifdef USE_PTHREAD
+
+/* seems to be undefined in MacOS X */
+#ifndef PTHREAD_CANCELED
+# define PTHREAD_CANCELED ((void *) -1)
+#endif
+
+/**
+ */
+#if defined (__APPLE__) && defined (__MACH__)
+static void
+thread_exit_handler( int signo )
+{
+ DBG( 2, "signal(%i) caught, calling pthread_exit now...\n", signo );
+ pthread_exit( PTHREAD_CANCELED );
+}
+#endif
+
+
+static void*
+local_thread( void *arg )
+{
+ static int status;
+ pThreadDataDef ltd = (pThreadDataDef)arg;
+
+#if defined (__APPLE__) && defined (__MACH__)
+ struct sigaction act;
+
+ sigemptyset(&(act.sa_mask));
+ act.sa_flags = 0;
+ act.sa_handler = thread_exit_handler;
+ sigaction( SIGUSR2, &act, 0 );
+#else
+ int old;
+
+ pthread_setcancelstate( PTHREAD_CANCEL_ENABLE, &old );
+ pthread_setcanceltype ( PTHREAD_CANCEL_ASYNCHRONOUS, &old );
+#endif
+
+ DBG( 2, "thread started, calling func() now...\n" );
+
+ status = ltd->func( ltd->func_data );
+
+ /* so sanei_thread_get_status() will work correctly... */
+ ltd->status = status;
+
+ DBG( 2, "func() done - status = %d\n", status );
+
+ /* return the status, so pthread_join is able to get it*/
+ pthread_exit((void*)&status );
+}
+
+/**
+ */
+static void
+restore_sigpipe( void )
+{
+ struct sigaction act;
+
+ if( sigaction( SIGPIPE, NULL, &act ) == 0 ) {
+
+ if( act.sa_handler == SIG_IGN ) {
+ sigemptyset( &act.sa_mask );
+ act.sa_flags = 0;
+ act.sa_handler = SIG_DFL;
+
+ DBG( 2, "restoring SIGPIPE to SIG_DFL\n" );
+ sigaction( SIGPIPE, &act, NULL );
+ }
+ }
+}
+
+#else /* the process stuff */
+
+static int
+eval_wp_result( int pid, int wpres, int pf )
+{
+ int retval = SANE_STATUS_IO_ERROR;
+
+ if( wpres == pid ) {
+
+ if( WIFEXITED(pf)) {
+ retval = WEXITSTATUS(pf);
+ } else {
+
+ if( !WIFSIGNALED(pf)) {
+ retval = SANE_STATUS_GOOD;
+ } else {
+ DBG( 1, "Child terminated by signal %d\n", WTERMSIG(pf));
+ if( WTERMSIG(pf) == SIGTERM )
+ retval = SANE_STATUS_GOOD;
+ }
+ }
+ }
+ return retval;
+}
+#endif
+
+int
+sanei_thread_begin( int (func)(void *args), void* args )
+{
+ int pid;
+#ifdef USE_PTHREAD
+ struct sigaction act;
+ pthread_t thread;
+
+ /* if signal handler for SIGPIPE is SIG_DFL, replace by SIG_IGN */
+ if( sigaction( SIGPIPE, NULL, &act ) == 0 ) {
+
+ if( act.sa_handler == SIG_DFL ) {
+ sigemptyset( &act.sa_mask );
+ act.sa_flags = 0;
+ act.sa_handler = SIG_IGN;
+
+ DBG( 2, "setting SIGPIPE to SIG_IGN\n" );
+ sigaction( SIGPIPE, &act, NULL );
+ }
+ }
+
+ td.func = func;
+ td.func_data = args;
+
+ pid = pthread_create( &thread, NULL, local_thread, &td );
+ usleep( 1 );
+
+ if ( pid != 0 ) {
+ DBG( 1, "pthread_create() failed with %d\n", pid );
+ return -1;
+ }
+
+ DBG( 2, "pthread_create() created thread %d\n", (int)thread );
+ return (int)thread;
+#else
+ pid = fork();
+ if( pid < 0 ) {
+ DBG( 1, "fork() failed\n" );
+ return -1;
+ }
+
+ if( pid == 0 ) {
+
+ /* run in child context... */
+ int status = func( args );
+
+ /* don't use exit() since that would run the atexit() handlers */
+ _exit( status );
+ }
+
+ /* parents return */
+ return pid;
+#endif
+}
+
+int
+sanei_thread_sendsig( int pid, int sig )
+{
+#ifdef USE_PTHREAD
+ DBG(2, "sanei_thread_sendsig() %d to thread(id=%d)\n", sig, pid);
+ return pthread_kill((pthread_t)pid, sig );
+#else
+ DBG(2, "sanei_thread_sendsig() %d to process (id=%d)\n", sig, pid);
+ return kill( pid, sig );
+#endif
+}
+
+int
+sanei_thread_waitpid( int pid, int *status )
+{
+#ifdef USE_PTHREAD
+ int *ls;
+#else
+ int ls;
+#endif
+ int result, stat;
+
+ stat = 0;
+
+ DBG(2, "sanei_thread_waitpid() - %d\n", pid);
+#ifdef USE_PTHREAD
+ result = pthread_join((pthread_t)pid, (void*)&ls );
+
+ if( 0 == result ) {
+ if( PTHREAD_CANCELED == ls ) {
+ DBG(2, "* thread has been canceled!\n" );
+ stat = SANE_STATUS_GOOD;
+ } else {
+ stat = *ls;
+ }
+ DBG(2, "* result = %d (%p)\n", stat, (void*)status );
+ result = pid;
+ }
+ /* call detach in any case to make sure that the thread resources
+ * will be freed, when the thread has terminated
+ */
+ DBG(2, "* detaching thread(%d)\n", pid );
+ pthread_detach((pthread_t)pid);
+ if (status)
+ *status = stat;
+
+ restore_sigpipe();
+#else
+ result = waitpid( pid, &ls, 0 );
+ if((result < 0) && (errno == ECHILD)) {
+ stat = SANE_STATUS_GOOD;
+ result = pid;
+ } else {
+ stat = eval_wp_result( pid, result, ls );
+ DBG(2, "* result = %d (%p)\n", stat, (void*)status );
+ }
+ if( status )
+ *status = stat;
+#endif
+ return result;
+}
+
+#endif /* HAVE_OS2_H */
+
+SANE_Status
+sanei_thread_get_status( int pid )
+{
+#if defined USE_PTHREAD || defined HAVE_OS2_H
+ _VAR_NOT_USED( pid );
+
+ return td.status;
+#else
+ int ls, stat, result;
+
+ stat = SANE_STATUS_IO_ERROR;
+ if( pid > 0 ) {
+
+ result = waitpid( pid, &ls, WNOHANG );
+
+ stat = eval_wp_result( pid, result, ls );
+ }
+ return stat;
+#endif
+}
+
+/* END sanei_thread.c .......................................................*/