/* SPDX-License-Identifier: BSD-2-Clause */
/**
* @file
*
* @brief User print interface to the bspIO print plug in.
*
* This include file defines the user interface to kernel print methods.
*/
/*
* Copyright (c) 2016 Chris Johns <chrisj@rtems.org>
* All rights reserved.
*
* 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.
*/
#ifndef _RTEMS_PRINTER_H
#define _RTEMS_PRINTER_H
#include <rtems/print.h>
#include <rtems/chain.h>
#include <rtems/rtems/intr.h>
#include <rtems/rtems/tasks.h>
#include <stdio.h>
#include <string.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @addtogroup RTEMSPrintSupport
*
* @{
*/
/**
* Type definition for function which can be plugged in to certain reporting
* routines to redirect the output.
*
* Use the RTEMS Print interface to call these functions. Do not directly use
* them.
*
* If the user provides their own printer, then they may redirect those reports
* as they see fit.
*/
typedef int (*rtems_print_printer)(void *, const char *format, va_list ap);
/**
* Type definition for the printer structure used to access the kernel print
* support.
*/
struct rtems_printer {
void *context;
rtems_print_printer printer;
};
/**
* @brief check if the printer is valid.
*
* @param[in] printer Pointer to the printer structure.
*
* @return true The printer is valid else false is returned.
*/
static inline bool rtems_print_printer_valid(const rtems_printer *printer)
{
return printer != NULL && printer->printer != NULL;
}
/**
* @brief Initializes the printer to print nothing.
*
* An empty printer prints nothing. You can use this to implement an enable and
* disable type print implementation.
*
* @param[in] printer Pointer to the printer structure.
*/
static inline void rtems_print_printer_empty(rtems_printer *printer)
{
printer->context = NULL;
printer->printer = NULL;
}
/**
* @brief Initializes the printer to print via printk().
*
* @param[in] printer Pointer to the printer structure.
*/
void rtems_print_printer_printk(rtems_printer *printer);
/**
* @brief Initializes the printer to print via printf().
*
* @param[in] printer Pointer to the printer structure.
*/
void rtems_print_printer_printf(rtems_printer *printer);
/**
* @brief Initializes the printer to print via fprintf() using the specified
* file stream.
*
* @param[in] printer Pointer to the printer structure.
*/
void rtems_print_printer_fprintf(rtems_printer *printer, FILE *file);
/**
* @brief Initializes the printer to print via fprintf() using an unbuffered
* FILE stream with output through rtems_putc().
*
* @param[in] printer Pointer to the printer structure.
*/
void rtems_print_printer_fprintf_putc(rtems_printer *printer);
typedef struct {
rtems_id task;
RTEMS_INTERRUPT_LOCK_MEMBER( lock )
rtems_chain_control free_buffers;
rtems_chain_control todo_buffers;
size_t task_stack_size;
rtems_task_priority task_priority;
int fd;
void *buffer_table;
size_t buffer_count;
size_t buffer_size;
} rtems_printer_task_context;
static inline void rtems_printer_task_initialize(
rtems_printer_task_context *context
)
{
/*
* Some C++ compiler think that the structure is complex enough to need a
* proper constructor. Cast to void * to silence a warning.
*/
memset( (void *) context, 0, sizeof( *context ) );
}
static inline void rtems_printer_task_set_stack_size(
rtems_printer_task_context *context,
size_t stack_size
)
{
context->task_stack_size = stack_size;
}
static inline void rtems_printer_task_set_priority(
rtems_printer_task_context *context,
rtems_task_priority priority
)
{
context->task_priority = priority;
}
static inline void rtems_printer_task_set_file_descriptor(
rtems_printer_task_context *context,
int fd
)
{
context->fd = fd;
}
static inline void rtems_printer_task_set_buffer_table(
rtems_printer_task_context *context,
void *buffer_table
)
{
context->buffer_table = buffer_table;
}
static inline void rtems_printer_task_set_buffer_count(
rtems_printer_task_context *context,
size_t buffer_count
)
{
context->buffer_count = buffer_count;
}
static inline void rtems_printer_task_set_buffer_size(
rtems_printer_task_context *context,
size_t buffer_size
)
{
context->buffer_size = buffer_size;
}
/**
* @brief Creates a printer task.
*
* Print requests via rtems_printf() or rtems_vprintf() using a printer task
* printer are output to a buffer and then placed on a work queue in FIFO
* order. The work queue is emptied by the printer task. The printer task
* writes the buffer content to the file descriptor specified by the context.
* Buffers are allocated from a pool of buffers as specified by the context.
*
* @param[in] printer Pointer to the printer structure.
* @param[in] context The initialized printer task context.
*
* @retval 0 Successful operation.
* @retval EINVAL Invalid context parameters.
* @retval ENOMEM Not enough resources.
*/
int rtems_print_printer_task(
rtems_printer *printer,
rtems_printer_task_context *context
);
/**
* @brief Drains the work queue of the printer task.
*
* Waits until all output buffers in the work queue at the time of this
* function call are written to the file descriptor and an fsync() completed.
*
* The printer task must be successfully started via rtems_print_printer_task()
* before this function can be used. Otherwise, the behaviour is undefined.
*
* @param[in] context The printer task context of a successfully started
* printer task.
*/
void rtems_printer_task_drain(rtems_printer_task_context *context);
/** @} */
#ifdef __cplusplus
}
#endif
#endif /* _RTEMS_PRINTER_H */
