incubator-nuttx/include/nuttx/streams.h

467 lines
16 KiB
C

/****************************************************************************
* include/nuttx/streams.h
*
* Copyright (C) 2009, 2011-2012, 2014-2016 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.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_STREAMS_H
#define __INCLUDE_NUTTX_STREAMS_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdio.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Public Types
****************************************************************************/
/* These are the generic representations of a streams used by the NuttX */
struct lib_instream_s;
typedef int (*lib_getc_t)(FAR struct lib_instream_s *this);
struct lib_outstream_s;
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; /* Get one character from the instream */
int nget; /* Total number of characters gotten. Written
* by get method, readable by user */
};
struct lib_outstream_s
{
lib_putc_t put; /* Put one character to the outstream */
lib_flush_t flush; /* Flush any buffered characters in the outstream */
int nput; /* Total number of characters put. Written
* by put method, readable by user */
};
/* Seek-able streams */
struct lib_sistream_s;
typedef int (*lib_sigetc_t)(FAR struct lib_sistream_s *this);
typedef off_t (*lib_siseek_t)(FAR struct lib_sistream_s *this, off_t offset,
int whence);
struct lib_sostream_s;
typedef void (*lib_soputc_t)(FAR struct lib_sostream_s *this, int ch);
typedef int (*lib_soflush_t)(FAR struct lib_sostream_s *this);
typedef off_t (*lib_soseek_t)(FAR struct lib_sostream_s *this, off_t offset,
int whence);
struct lib_sistream_s
{
lib_sigetc_t get; /* Get one character from the instream */
lib_siseek_t seek; /* Seek to a position in the instream */
int nget; /* Total number of characters gotten. Written
* by get method, readable by user */
};
struct lib_sostream_s
{
lib_soputc_t put; /* Put one character to the outstream */
lib_soflush_t flush; /* Flush any buffered characters in the outstream */
lib_soseek_t seek; /* Seek a position in the output stream */
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 */
size_t 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 */
size_t buflen; /* Size of the buffer in bytes */
};
struct lib_memsistream_s
{
struct lib_sistream_s public;
FAR const char *buffer; /* Address of first byte in the buffer */
size_t offset; /* Current buffer offset in bytes */
size_t buflen; /* Size of the buffer in bytes */
};
struct lib_memsostream_s
{
struct lib_sostream_s public;
FAR char *buffer; /* Address of first byte in the buffer */
size_t offset; /* Current buffer offset in bytes */
size_t 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;
};
struct lib_stdsistream_s
{
struct lib_sistream_s public;
FAR FILE *stream;
};
struct lib_stdsostream_s
{
struct lib_sostream_s public;
FAR FILE *stream;
};
/* These are streams that operate on a file descriptor */
struct lib_rawinstream_s
{
struct lib_instream_s public;
int fd;
};
struct lib_rawoutstream_s
{
struct lib_outstream_s public;
int fd;
};
struct lib_rawsistream_s
{
struct lib_sistream_s public;
int fd;
};
struct lib_rawsostream_s
{
struct lib_sostream_s public;
int fd;
};
/* This is a special stream that does buffered character I/O. NOTE that is
* CONFIG_SYSLOG_BUFFER is not defined, it is the same as struct
* lib_outstream_s
*/
struct iob_s; /* Forward reference */
struct lib_syslogstream_s
{
struct lib_outstream_s public;
#ifdef CONFIG_SYSLOG_BUFFER
FAR struct iob_s *iob;
#endif
};
/****************************************************************************
* Public Data
****************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
# define EXTERN extern "C"
extern "C"
{
#else
# define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: lib_meminstream, lib_memoutstream, lib_memsistream, lib_memsostream
*
* Description:
* Initializes a stream for use with a fixed-size memory buffer.
* Defined in lib/stdio/lib_meminstream.c and lib/stdio/lib_memoutstream.c.
* Seekable versions are defined in lib/stdio/lib_memsistream.c and
* lib/stdio/lib_memsostream.c.
*
* Input parameters:
* memstream - User allocated, uninitialized instance of struct
* lib_meminstream_s to be initialized.
* memstream - 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).
*
****************************************************************************/
void lib_meminstream(FAR struct lib_meminstream_s *instream,
FAR const char *bufstart, int buflen);
void lib_memoutstream(FAR struct lib_memoutstream_s *outstream,
FAR char *bufstart, int buflen);
void lib_memsistream(FAR struct lib_memsistream_s *instream,
FAR const char *bufstart, int buflen);
void lib_memsostream(FAR struct lib_memsostream_s *outstream,
FAR char *bufstart, int buflen);
/****************************************************************************
* Name: lib_stdinstream, lib_stdoutstream
*
* Description:
* Initializes a stream for use with a FILE instance.
* Defined in lib/stdio/lib_stdinstream.c and lib/stdio/lib_stdoutstream.c
*
* Input parameters:
* instream - User allocated, uninitialized instance of struct
* lib_stdinstream_s to be initialized.
* outstream - 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).
*
****************************************************************************/
void lib_stdinstream(FAR struct lib_stdinstream_s *instream,
FAR FILE *stream);
void lib_stdoutstream(FAR struct lib_stdoutstream_s *outstream,
FAR FILE *stream);
void lib_stdsistream(FAR struct lib_stdsistream_s *instream,
FAR FILE *stream);
void lib_stdsostream(FAR struct lib_stdsostream_s *outstream,
FAR FILE *stream);
/****************************************************************************
* Name: lib_rawinstream, lib_rawoutstream, lib_rawsistream, and
* lib_rawsostream,
*
* Description:
* Initializes a stream for use with a file descriptor.
* Defined in lib/stdio/lib_rawinstream.c and lib/stdio/lib_rawoutstream.c.
* Seekable versions are defined in lib/stdio/lib_rawsistream.c and
* lib/stdio/lib_rawsostream.c
*
* Input parameters:
* instream - User allocated, uninitialized instance of struct
* lib_rawinstream_s to be initialized.
* outstream - 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).
*
****************************************************************************/
void lib_rawinstream(FAR struct lib_rawinstream_s *instream, int fd);
void lib_rawoutstream(FAR struct lib_rawoutstream_s *outstream, int fd);
void lib_rawsistream(FAR struct lib_rawsistream_s *instream, int fd);
void lib_rawsostream(FAR struct lib_rawsostream_s *outstream, int fd);
/****************************************************************************
* Name: lib_lowoutstream
*
* Description:
* Initializes a stream for use with low-level, architecture-specific output.
* Defined in ib/stdio/lib_lowoutstream.c
*
* Input parameters:
* lowoutstream - User allocated, uninitialized instance of struct
* lib_lowoutstream_s to be initialized.
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
#ifdef CONFIG_ARCH_LOWPUTC
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/stdio/lib_zeroinstream.c
* o The stream created by lib_nullinstream will return only EOF.
* Defined in lib/stdio/lib_nullinstream.c
* o The stream created by lib_nulloutstream will write all data to the
* bit-bucket. Defined in lib/stdio/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).
*
****************************************************************************/
void lib_zeroinstream(FAR struct lib_instream_s *zeroinstream);
void lib_nullinstream(FAR struct lib_instream_s *nullinstream);
void lib_nulloutstream(FAR struct lib_outstream_s *nulloutstream);
/****************************************************************************
* Name: syslogstream_create
*
* Description:
* Initializes a stream for use with the configured syslog interface.
* Only accessible from with the OS SYSLOG logic.
*
* Input parameters:
* stream - User allocated, uninitialized instance of struct
* lib_lowoutstream_s to be initialized.
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
void syslogstream_create(FAR struct lib_syslogstream_s *stream);
/****************************************************************************
* Name: syslogstream_destroy
*
* Description:
* Free resources held by the syslog stream.
*
* Input parameters:
* stream - User allocated, uninitialized instance of struct
* lib_lowoutstream_s to be initialized.
*
* Returned Value:
* None (Resources freed).
*
****************************************************************************/
#ifdef CONFIG_SYSLOG_BUFFER
void syslogstream_destroy(FAR struct lib_syslogstream_s *stream);
#else
# define syslogstream_destroy(s)
#endif
/****************************************************************************
* Name: emergstream
*
* Description:
* Initializes a stream for use with the configured emergency syslog
* interface. Only accessible from with the OS SYSLOG logic.
*
* Input parameters:
* stream - User allocated, uninitialized instance of struct
* lib_lowoutstream_s to be initialized.
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
void emergstream(FAR struct lib_outstream_s *stream);
/****************************************************************************
* Name: lib_noflush
*
* Description:
* lib_noflush() provides a common, dummy flush method for output streams
* that are not flushable.
*
* Return:
* Always returns OK
*
****************************************************************************/
int lib_noflush(FAR struct lib_outstream_s *stream);
/****************************************************************************
* Name: lib_snoflush
*
* Description:
* lib_snoflush() provides a common, dummy flush method for seekable output
* streams that are not flushable.
* is selected.
*
* Return:
* Always returns OK
*
****************************************************************************/
int lib_snoflush(FAR struct lib_sostream_s *this);
/****************************************************************************
* Name: lib_sprintf and lib_vsprintf
*
* Description:
* Stream-oriented versions of sprintf and vsprintf.
*
****************************************************************************/
int lib_sprintf(FAR struct lib_outstream_s *obj,
FAR const IPTR char *fmt, ...);
int lib_vsprintf(FAR struct lib_outstream_s *obj,
FAR const IPTR char *src, va_list ap);
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __INCLUDE_NUTTX_STREAMS_H */