incubator-nuttx/libs/libc/syslog/lib_setlogmask.c

108 lines
4.3 KiB
C

/****************************************************************************
* lib/syslog/lib_setlogmask.c
*
* Copyright (C) 2007-2009, 2011-2012, 2016 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <syslog.h>
#include <nuttx/irq.h>
#include "syslog/syslog.h"
/****************************************************************************
* Public Data
****************************************************************************/
/* The currently enabled set of syslog priorities */
uint8_t g_syslog_mask = LOG_ALL;
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: setlogmask
*
* Description:
* The setlogmask() function sets the logmask and returns the previous
* mask. If the mask argument is 0, the current logmask is not modified.
*
* The SYSLOG priorities are: LOG_EMERG, LOG_ALERT, LOG_CRIT, LOG_ERR,
* LOG_WARNING, LOG_NOTICE, LOG_INFO, and LOG_DEBUG. The bit corresponding
* to a priority p is LOG_MASK(p); LOG_UPTO(p) provides the mask of all
* priorities in the above list up to and including p.
*
* Per OpenGroup.org "If the maskpri argument is 0, the current log mask
* is not modified." In this implementation, the value zero is permitted
* in order to disable all syslog levels.
*
* REVISIT: Per POSIX the syslog mask should be a per-process value but in
* NuttX, the scope of the mask is dependent on the nature of the build:
*
* Flat Build: There is one, global SYSLOG mask that controls all output.
* Protected Build: There are two SYSLOG masks. One within the kernel
* that controls only kernel output. And one in user-space that controls
* only user SYSLOG output.
* Kernel Build: The kernel build is compliant with the POSIX requirement:
* There will be one mask for each user process, controlling the SYSLOG
* output only form that process. There will be a separate mask
* accessible only in the kernel code to control kernel SYSLOG output.
*
****************************************************************************/
int setlogmask(int mask)
{
uint8_t oldmask;
irqstate_t flags;
/* These operations must be exclusive with respect to other threads as well
* as interrupts.
*/
flags = enter_critical_section();
oldmask = g_syslog_mask;
g_syslog_mask = (uint8_t)mask;
leave_critical_section(flags);
return oldmask;
}