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/* SPDX-License-Identifier: BSD-2-Clause */
/*
* COPYRIGHT (c) 1989-2011.
* On-Line Applications Research Corporation (OAR).
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 OWNER OR CONTRIBUTORS 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "test_support.h"
#include "tmacros.h"
#include <unistd.h>
#include <rtems/bspIo.h>
#include <rtems/counter.h>
static rtems_id locked_print_semaphore; /* synchronisation semaphore */
static int locked_printf_plugin(void *context, const char *fmt, va_list ap)
{
(void) context;
return locked_vprintf(fmt, ap);
}
void locked_print_initialize(void)
{
rtems_status_code sc;
static bool initted = false;
if ( initted )
return;
initted = true;
/* Create/verify synchronisation semaphore */
sc = rtems_semaphore_create(
rtems_build_name ('S', 'E', 'M', '1'),
1,
RTEMS_LOCAL |
RTEMS_BINARY_SEMAPHORE |
RTEMS_PRIORITY_CEILING |
RTEMS_PRIORITY,
1,
&locked_print_semaphore
);
directive_failed( sc, "rtems_semaphore_create" );
/*
* Set up the printer to use the locked printf printer.
*/
rtems_test_printer.context = NULL;
rtems_test_printer.printer = locked_printf_plugin;
}
int locked_vprintf(const char *fmt, va_list ap)
{
int rv;
rtems_status_code sc;
locked_print_initialize();
/* Lock semaphore without releasing the cpu */
sc = rtems_semaphore_obtain( locked_print_semaphore, RTEMS_NO_WAIT, 0 );
if ( sc != RTEMS_SUCCESSFUL ) {
uint8_t e;
rtems_counter_ticks w;
/* Use exponential backoff to avoid a livelock */
getentropy( &e, sizeof( e ) );
w = e + 1;
do {
rtems_counter_delay_ticks( w );
w *= 2;
sc = rtems_semaphore_obtain( locked_print_semaphore, RTEMS_NO_WAIT, 0 );
} while (sc != RTEMS_SUCCESSFUL );
}
rv = vprintk(fmt, ap);
/* Release the semaphore */
rtems_semaphore_release( locked_print_semaphore );
return rv;
}
int locked_printf(const char *fmt, ...)
{
int rv;
va_list ap; /* points to each unnamed argument in turn */
va_start(ap, fmt); /* make ap point to 1st unnamed arg */
rv = locked_vprintf(fmt, ap);
va_end(ap); /* clean up when done */
return rv;
}
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