Edit File: jas_stream.h
/* * Copyright (c) 1999-2000 Image Power, Inc. and the University of * British Columbia. * Copyright (c) 2001-2003 Michael David Adams. * All rights reserved. */ /* __START_OF_JASPER_LICENSE__ * * JasPer License Version 2.0 * * Copyright (c) 2001-2006 Michael David Adams * Copyright (c) 1999-2000 Image Power, Inc. * Copyright (c) 1999-2000 The University of British Columbia * * All rights reserved. * * Permission is hereby granted, free of charge, to any person (the * "User") obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without restriction, * including without limitation the rights to use, copy, modify, merge, * publish, distribute, and/or sell copies of the Software, and to permit * persons to whom the Software is furnished to do so, subject to the * following conditions: * * 1. The above copyright notices and this permission notice (which * includes the disclaimer below) shall be included in all copies or * substantial portions of the Software. * * 2. The name of a copyright holder shall not be used to endorse or * promote products derived from the Software without specific prior * written permission. * * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS * LICENSE. NO USE OF THE SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER * THIS DISCLAIMER. THE SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS * "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL * INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. NO ASSURANCES ARE * PROVIDED BY THE COPYRIGHT HOLDERS THAT THE SOFTWARE DOES NOT INFRINGE * THE PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OF ANY OTHER ENTITY. * EACH COPYRIGHT HOLDER DISCLAIMS ANY LIABILITY TO THE USER FOR CLAIMS * BROUGHT BY ANY OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL * PROPERTY RIGHTS OR OTHERWISE. AS A CONDITION TO EXERCISING THE RIGHTS * GRANTED HEREUNDER, EACH USER HEREBY ASSUMES SOLE RESPONSIBILITY TO SECURE * ANY OTHER INTELLECTUAL PROPERTY RIGHTS NEEDED, IF ANY. THE SOFTWARE * IS NOT FAULT-TOLERANT AND IS NOT INTENDED FOR USE IN MISSION-CRITICAL * SYSTEMS, SUCH AS THOSE USED IN THE OPERATION OF NUCLEAR FACILITIES, * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL * SYSTEMS, DIRECT LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH * THE FAILURE OF THE SOFTWARE OR SYSTEM COULD LEAD DIRECTLY TO DEATH, * PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH * RISK ACTIVITIES"). THE COPYRIGHT HOLDERS SPECIFICALLY DISCLAIM ANY * EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES. * * __END_OF_JASPER_LICENSE__ */ /* * I/O Stream Class * * $Id$ */ #ifndef JAS_STREAM_H #define JAS_STREAM_H /******************************************************************************\ * Includes. \******************************************************************************/ #include <jasper/jas_config.h> #include <stdio.h> #if defined(HAVE_FCNTL_H) #include <fcntl.h> #endif #include <string.h> #if defined(HAVE_UNISTD_H) #include <unistd.h> #endif #include <jasper/jas_types.h> #ifdef __cplusplus extern "C" { #endif /******************************************************************************\ * Constants. \******************************************************************************/ /* On most UNIX systems, we probably need to define O_BINARY ourselves. */ #ifndef O_BINARY #define O_BINARY 0 #endif /* * Stream open flags. */ /* The stream was opened for reading. */ #define JAS_STREAM_READ 0x0001 /* The stream was opened for writing. */ #define JAS_STREAM_WRITE 0x0002 /* The stream was opened for appending. */ #define JAS_STREAM_APPEND 0x0004 /* The stream was opened in binary mode. */ #define JAS_STREAM_BINARY 0x0008 /* The stream should be created/truncated. */ #define JAS_STREAM_CREATE 0x0010 /* * Stream buffering flags. */ /* The stream is unbuffered. */ #define JAS_STREAM_UNBUF 0x0000 /* The stream is line buffered. */ #define JAS_STREAM_LINEBUF 0x0001 /* The stream is fully buffered. */ #define JAS_STREAM_FULLBUF 0x0002 /* The buffering mode mask. */ #define JAS_STREAM_BUFMODEMASK 0x000f /* The memory associated with the buffer needs to be deallocated when the stream is destroyed. */ #define JAS_STREAM_FREEBUF 0x0008 /* The buffer is currently being used for reading. */ #define JAS_STREAM_RDBUF 0x0010 /* The buffer is currently being used for writing. */ #define JAS_STREAM_WRBUF 0x0020 /* * Stream error flags. */ /* The end-of-file has been encountered (on reading). */ #define JAS_STREAM_EOF 0x0001 /* An I/O error has been encountered on the stream. */ #define JAS_STREAM_ERR 0x0002 /* The read/write limit has been exceeded. */ #define JAS_STREAM_RWLIMIT 0x0004 /* The error mask. */ #define JAS_STREAM_ERRMASK \ (JAS_STREAM_EOF | JAS_STREAM_ERR | JAS_STREAM_RWLIMIT) /* * Other miscellaneous constants. */ /* The default buffer size (for fully-buffered operation). */ #define JAS_STREAM_BUFSIZE 8192 /* The default permission mask for file creation. */ #define JAS_STREAM_PERMS 0666 /* The maximum number of characters that can always be put back on a stream. */ #define JAS_STREAM_MAXPUTBACK 16 /******************************************************************************\ * Types. \******************************************************************************/ /* * Generic file object. */ typedef void jas_stream_obj_t; /* * Generic file object operations. */ typedef struct { /* Read characters from a file object. */ int (*read_)(jas_stream_obj_t *obj, char *buf, int cnt); /* Write characters to a file object. */ int (*write_)(jas_stream_obj_t *obj, char *buf, int cnt); /* Set the position for a file object. */ long (*seek_)(jas_stream_obj_t *obj, long offset, int origin); /* Close a file object. */ int (*close_)(jas_stream_obj_t *obj); } jas_stream_ops_t; /* * Stream object. */ typedef struct { /* The mode in which the stream was opened. */ int openmode_; /* The buffering mode. */ int bufmode_; /* The stream status. */ int flags_; /* The start of the buffer area to use for reading/writing. */ uchar *bufbase_; /* The start of the buffer area excluding the extra initial space for character putback. */ uchar *bufstart_; /* The buffer size. */ int bufsize_; /* The current position in the buffer. */ uchar *ptr_; /* The number of characters that must be read/written before the buffer needs to be filled/flushed. */ int cnt_; /* A trivial buffer to be used for unbuffered operation. */ uchar tinybuf_[JAS_STREAM_MAXPUTBACK + 1]; /* The operations for the underlying stream file object. */ jas_stream_ops_t *ops_; /* The underlying stream file object. */ jas_stream_obj_t *obj_; /* The number of characters read/written. */ long rwcnt_; /* The maximum number of characters that may be read/written. */ long rwlimit_; } jas_stream_t; /* * Regular file object. */ /* * File descriptor file object. */ typedef struct { int fd; int flags; char pathname[L_tmpnam + 1]; } jas_stream_fileobj_t; #define JAS_STREAM_FILEOBJ_DELONCLOSE 0x01 #define JAS_STREAM_FILEOBJ_NOCLOSE 0x02 /* * Memory file object. */ typedef struct { /* The data associated with this file. */ uchar *buf_; /* The allocated size of the buffer for holding file data. */ int bufsize_; /* The length of the file. */ int_fast32_t len_; /* The seek position. */ int_fast32_t pos_; /* Is the buffer growable? */ int growable_; /* Was the buffer allocated internally? */ int myalloc_; } jas_stream_memobj_t; /******************************************************************************\ * Macros/functions for opening and closing streams. \******************************************************************************/ /* Open a file as a stream. */ jas_stream_t *jas_stream_fopen(const char *filename, const char *mode); /* Open a memory buffer as a stream. */ jas_stream_t *jas_stream_memopen(char *buf, int bufsize); /* Open a file descriptor as a stream. */ jas_stream_t *jas_stream_fdopen(int fd, const char *mode); /* Open a stdio stream as a stream. */ jas_stream_t *jas_stream_freopen(const char *path, const char *mode, FILE *fp); /* Open a temporary file as a stream. */ jas_stream_t *jas_stream_tmpfile(void); /* Close a stream. */ int jas_stream_close(jas_stream_t *stream); /******************************************************************************\ * Macros/functions for getting/setting the stream state. \******************************************************************************/ /* Get the EOF indicator for a stream. */ #define jas_stream_eof(stream) \ (((stream)->flags_ & JAS_STREAM_EOF) != 0) /* Get the error indicator for a stream. */ #define jas_stream_error(stream) \ (((stream)->flags_ & JAS_STREAM_ERR) != 0) /* Clear the error indicator for a stream. */ #define jas_stream_clearerr(stream) \ ((stream)->flags_ &= ~(JAS_STREAM_ERR | JAS_STREAM_EOF)) /* Get the read/write limit for a stream. */ #define jas_stream_getrwlimit(stream) \ (((const jas_stream_t *)(stream))->rwlimit_) /* Set the read/write limit for a stream. */ int jas_stream_setrwlimit(jas_stream_t *stream, long rwlimit); /* Get the read/write count for a stream. */ #define jas_stream_getrwcount(stream) \ (((const jas_stream_t *)(stream))->rwcnt_) /* Set the read/write count for a stream. */ long jas_stream_setrwcount(jas_stream_t *stream, long rwcnt); /******************************************************************************\ * Macros/functions for I/O. \******************************************************************************/ /* Read a character from a stream. */ #if defined(DEBUG) #define jas_stream_getc(stream) jas_stream_getc_func(stream) #else #define jas_stream_getc(stream) jas_stream_getc_macro(stream) #endif /* Write a character to a stream. */ #if defined(DEBUG) #define jas_stream_putc(stream, c) jas_stream_putc_func(stream, c) #else #define jas_stream_putc(stream, c) jas_stream_putc_macro(stream, c) #endif /* Read characters from a stream into a buffer. */ int jas_stream_read(jas_stream_t *stream, void *buf, int cnt); /* Write characters from a buffer to a stream. */ int jas_stream_write(jas_stream_t *stream, const void *buf, int cnt); /* Write formatted output to a stream. */ int jas_stream_printf(jas_stream_t *stream, const char *fmt, ...); /* Write a string to a stream. */ int jas_stream_puts(jas_stream_t *stream, const char *s); /* Read a line of input from a stream. */ char *jas_stream_gets(jas_stream_t *stream, char *buf, int bufsize); /* Look at the next character to be read from a stream without actually removing it from the stream. */ #define jas_stream_peekc(stream) \ (((stream)->cnt_ <= 0) ? jas_stream_fillbuf(stream, 0) : \ ((int)(*(stream)->ptr_))) /* Put a character back on a stream. */ int jas_stream_ungetc(jas_stream_t *stream, int c); /******************************************************************************\ * Macros/functions for getting/setting the stream position. \******************************************************************************/ /* Is it possible to seek on this stream? */ int jas_stream_isseekable(jas_stream_t *stream); /* Set the current position within the stream. */ long jas_stream_seek(jas_stream_t *stream, long offset, int origin); /* Get the current position within the stream. */ long jas_stream_tell(jas_stream_t *stream); /* Seek to the beginning of a stream. */ int jas_stream_rewind(jas_stream_t *stream); /******************************************************************************\ * Macros/functions for flushing. \******************************************************************************/ /* Flush any pending output to a stream. */ int jas_stream_flush(jas_stream_t *stream); /******************************************************************************\ * Miscellaneous macros/functions. \******************************************************************************/ /* Copy data from one stream to another. */ int jas_stream_copy(jas_stream_t *dst, jas_stream_t *src, int n); /* Display stream contents (for debugging purposes). */ int jas_stream_display(jas_stream_t *stream, FILE *fp, int n); /* Consume (i.e., discard) characters from stream. */ int jas_stream_gobble(jas_stream_t *stream, int n); /* Write a character multiple times to a stream. */ int jas_stream_pad(jas_stream_t *stream, int n, int c); /* Get the size of the file associated with the specified stream. The specified stream must be seekable. */ long jas_stream_length(jas_stream_t *stream); /******************************************************************************\ * Internal functions. \******************************************************************************/ /* The following functions are for internal use only! If you call them directly, you will die a horrible, miserable, and painful death! */ /* Read a character from a stream. */ #define jas_stream_getc_macro(stream) \ ((!((stream)->flags_ & (JAS_STREAM_ERR | JAS_STREAM_EOF | \ JAS_STREAM_RWLIMIT))) ? \ (((stream)->rwlimit_ >= 0 && (stream)->rwcnt_ >= (stream)->rwlimit_) ? \ (stream->flags_ |= JAS_STREAM_RWLIMIT, EOF) : \ jas_stream_getc2(stream)) : EOF) #define jas_stream_getc2(stream) \ ((--(stream)->cnt_ < 0) ? jas_stream_fillbuf(stream, 1) : \ (++(stream)->rwcnt_, (int)(*(stream)->ptr_++))) /* Write a character to a stream. */ #define jas_stream_putc_macro(stream, c) \ ((!((stream)->flags_ & (JAS_STREAM_ERR | JAS_STREAM_EOF | \ JAS_STREAM_RWLIMIT))) ? \ (((stream)->rwlimit_ >= 0 && (stream)->rwcnt_ >= (stream)->rwlimit_) ? \ (stream->flags_ |= JAS_STREAM_RWLIMIT, EOF) : \ jas_stream_putc2(stream, c)) : EOF) #define jas_stream_putc2(stream, c) \ (((stream)->bufmode_ |= JAS_STREAM_WRBUF, --(stream)->cnt_ < 0) ? \ jas_stream_flushbuf((stream), (uchar)(c)) : \ (++(stream)->rwcnt_, (int)(*(stream)->ptr_++ = (c)))) /* These prototypes need to be here for the sake of the stream_getc and stream_putc macros. */ int jas_stream_fillbuf(jas_stream_t *stream, int getflag); int jas_stream_flushbuf(jas_stream_t *stream, int c); int jas_stream_getc_func(jas_stream_t *stream); int jas_stream_putc_func(jas_stream_t *stream, int c); #ifdef __cplusplus } #endif #endif