incubator-nuttx/include/nuttx/streams.h

277 lines
10 KiB
C

/****************************************************************************
* include/nuttx/streams.h
*
* Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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.
*
****************************************************************************/
#ifndef _INCLUDE_NUTTX_STREAMS_H
#define _INCLUDE_NUTTX_STREAMS_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdio.h>
/****************************************************************************
* Definitions
****************************************************************************/
/****************************************************************************
* Public Types
****************************************************************************/
/* These are the generic representations of a streams used by the NuttX */
struct lib_instream_s;
struct lib_outstream_s;
typedef int (*lib_getc_t)(FAR struct lib_instream_s *this);
typedef void (*lib_putc_t)(FAR struct lib_outstream_s *this, int ch);
typedef int (*lib_flush_t)(FAR struct lib_outstream_s *this);
struct lib_instream_s
{
lib_getc_t get; /* Pointer to function to get one character */
int nget; /* Total number of characters gotten. Written
* by get method, readable by user */
};
struct lib_outstream_s
{
lib_putc_t put; /* Pointer to function to put one character */
#ifdef CONFIG_STDIO_LINEBUFFER
lib_flush_t flush; /* Pointer to function flush buffered characters */
#endif
int nput; /* Total number of characters put. Written
* by put method, readable by user */
};
/* These are streams that operate on a fixed-sized block of memory */
struct lib_meminstream_s
{
struct lib_instream_s public;
FAR const char *buffer; /* Address of first byte in the buffer */
int buflen; /* Size of the buffer in bytes */
};
struct lib_memoutstream_s
{
struct lib_outstream_s public;
FAR char *buffer; /* Address of first byte in the buffer */
int buflen; /* Size of the buffer in bytes */
};
/* These are streams that operate on a FILE */
struct lib_stdinstream_s
{
struct lib_instream_s public;
FAR FILE *stream;
};
struct lib_stdoutstream_s
{
struct lib_outstream_s public;
FAR FILE *stream;
};
/* These are streams that operate on a file descriptor */
struct lib_rawoutstream_s
{
struct lib_outstream_s public;
int fd;
};
struct lib_rawinstream_s
{
struct lib_instream_s public;
int fd;
};
/****************************************************************************
* Public Variables
****************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
# define EXTERN extern "C"
extern "C"
{
#else
# define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: lib_meminstream, lib_memoutstream
*
* Description:
* Initializes a stream for use with a fixed-size memory buffer.
* Defined in lib/lib_meminstream.c and lib/lib_memoutstream.c
*
* Input parameters:
* meminstream - User allocated, uninitialized instance of struct
* lib_meminstream_s to be initialized.
* memoutstream - User allocated, uninitialized instance of struct
* lib_memoutstream_s to be initialized.
* bufstart - Address of the beginning of the fixed-size memory buffer
* buflen - Size of the fixed-sized memory buffer in bytes
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
EXTERN void lib_meminstream(FAR struct lib_meminstream_s *meminstream,
FAR const char *bufstart, int buflen);
EXTERN void lib_memoutstream(FAR struct lib_memoutstream_s *memoutstream,
FAR char *bufstart, int buflen);
/****************************************************************************
* Name: lib_stdinstream, lib_stdoutstream
*
* Description:
* Initializes a stream for use with a FILE instance.
* Defined in lib/lib_stdinstream.c and lib/lib_stdoutstream.c
*
* Input parameters:
* stdinstream - User allocated, uninitialized instance of struct
* lib_stdinstream_s to be initialized.
* stdoutstream - User allocated, uninitialized instance of struct
* lib_stdoutstream_s to be initialized.
* stream - User provided stream instance (must have been opened for
* the correct access).
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
EXTERN void lib_stdinstream(FAR struct lib_stdinstream_s *stdinstream,
FAR FILE *stream);
EXTERN void lib_stdoutstream(FAR struct lib_stdoutstream_s *stdoutstream,
FAR FILE *stream);
/****************************************************************************
* Name: lib_rawinstream, lib_rawoutstream
*
* Description:
* Initializes a stream for use with a file descriptor.
* Defined in lib/lib_rawinstream.c and lib/lib_rawoutstream.c
*
* Input parameters:
* rawinstream - User allocated, uninitialized instance of struct
* lib_rawinstream_s to be initialized.
* rawoutstream - User allocated, uninitialized instance of struct
* lib_rawoutstream_s to be initialized.
* fd - User provided file/socket descriptor (must have been opened
* for the correct access).
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
EXTERN void lib_rawinstream(FAR struct lib_rawinstream_s *rawinstream,
int fd);
EXTERN void lib_rawoutstream(FAR struct lib_rawoutstream_s *rawoutstream,
int fd);
/****************************************************************************
* Name: lib_lowinstream, lib_lowoutstream
*
* Description:
* Initializes a stream for use with low-level, architecture-specific I/O.
* Defined in lib/lib_lowinstream.c and lib/lib_lowoutstream.c
*
* Input parameters:
* lowinstream - User allocated, uninitialized instance of struct
* lib_lowinstream_s to be initialized.
* lowoutstream - User allocated, uninitialized instance of struct
* lib_lowoutstream_s to be initialized.
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
#ifdef CONFIG_ARCH_LOWGETC
EXTERN void lib_lowinstream(FAR struct lib_instream_s *lowinstream);
#endif
#ifdef CONFIG_ARCH_LOWPUTC
EXTERN void lib_lowoutstream(FAR struct lib_outstream_s *lowoutstream);
#endif
/****************************************************************************
* Name: lib_zeroinstream, lib_nullinstream, lib_nulloutstream
*
* Description:
* Initializes NULL streams:
*
* o The stream created by lib_zeroinstream will return an infinitely long
* stream of zeroes. Defined in lib/lib_zeroinstream.c
* o The stream created by lib_nullinstream will return only EOF.
* Defined in lib/lib_nullinstream.c
* o The stream created by lib_nulloutstream will write all data to the
* bit-bucket. Defined in lib/lib_nulloutstream.c
*
* Input parameters:
* zeroinstream - User allocated, uninitialized instance of struct
* lib_instream_s to be initialized.
* nullinstream - User allocated, uninitialized instance of struct
* lib_instream_s to be initialized.
* nulloutstream - User allocated, uninitialized instance of struct
* lib_outstream_s to be initialized.
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
EXTERN void lib_zeroinstream(FAR struct lib_instream_s *zeroinstream);
EXTERN void lib_nullinstream(FAR struct lib_instream_s *nullinstream);
EXTERN void lib_nulloutstream(FAR struct lib_outstream_s *nulloutstream);
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* _INCLUDE_NUTTX_STREAMS_H */