JasPer  2.0.32
jas_stream.h
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1 /*
2  * Copyright (c) 1999-2000 Image Power, Inc. and the University of
3  * British Columbia.
4  * Copyright (c) 2001-2003 Michael David Adams.
5  * All rights reserved.
6  */
7 
8 /* __START_OF_JASPER_LICENSE__
9  *
10  * JasPer License Version 2.0
11  *
12  * Copyright (c) 2001-2006 Michael David Adams
13  * Copyright (c) 1999-2000 Image Power, Inc.
14  * Copyright (c) 1999-2000 The University of British Columbia
15  *
16  * All rights reserved.
17  *
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19  * "User") obtaining a copy of this software and associated documentation
20  * files (the "Software"), to deal in the Software without restriction,
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23  * persons to whom the Software is furnished to do so, subject to the
24  * following conditions:
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32  * written permission.
33  *
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36  * THIS DISCLAIMER. THE SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS
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58  * RISK ACTIVITIES"). THE COPYRIGHT HOLDERS SPECIFICALLY DISCLAIM ANY
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60  *
61  * __END_OF_JASPER_LICENSE__
62  */
63 
69 #ifndef JAS_STREAM_H
70 #define JAS_STREAM_H
71 
72 /******************************************************************************\
73 * Includes.
74 \******************************************************************************/
75 
76 /* The configuration header file should be included first. */
77 #include <jasper/jas_config.h> /* IWYU pragma: export */
78 
79 #include <stdio.h>
80 #include <limits.h>
81 #if defined(JAS_HAVE_FCNTL_H)
82 #include <fcntl.h>
83 #endif
84 #include <jasper/jas_types.h>
85 
86 #ifdef __cplusplus
87 extern "C" {
88 #endif
89 
95 /******************************************************************************\
96 * Constants.
97 \******************************************************************************/
98 
99 /* On most UNIX systems, we probably need to define O_BINARY ourselves. */
100 #ifndef O_BINARY
101 #define O_BINARY 0
102 #endif
103 
104 #ifdef PATH_MAX
105 #define JAS_PATH_MAX PATH_MAX
106 #else
107 #define JAS_PATH_MAX 4096
108 #endif
109 
110 /*
111  * Stream open flags.
112  */
113 
114 /* The stream was opened for reading. */
115 #define JAS_STREAM_READ 0x0001
116 /* The stream was opened for writing. */
117 #define JAS_STREAM_WRITE 0x0002
118 /* The stream was opened for appending. */
119 #define JAS_STREAM_APPEND 0x0004
120 /* The stream was opened in binary mode. */
121 #define JAS_STREAM_BINARY 0x0008
122 /* The stream should be created/truncated. */
123 #define JAS_STREAM_CREATE 0x0010
124 
125 /*
126  * Stream buffering flags.
127  */
128 
129 /* The stream is unbuffered. */
130 #define JAS_STREAM_UNBUF 0x0000
131 /* The stream is line buffered. */
132 #define JAS_STREAM_LINEBUF 0x0001
133 /* The stream is fully buffered. */
134 #define JAS_STREAM_FULLBUF 0x0002
135 /* The buffering mode mask. */
136 #define JAS_STREAM_BUFMODEMASK 0x000f
137 
138 /* The memory associated with the buffer needs to be deallocated when the
139  stream is destroyed. */
140 #define JAS_STREAM_FREEBUF 0x0008
141 /* The buffer is currently being used for reading. */
142 #define JAS_STREAM_RDBUF 0x0010
143 /* The buffer is currently being used for writing. */
144 #define JAS_STREAM_WRBUF 0x0020
145 
146 /*
147  * Stream error flags.
148  */
149 
150 /* The end-of-file has been encountered (on reading). */
151 #define JAS_STREAM_EOF 0x0001
152 /* An I/O error has been encountered on the stream. */
153 #define JAS_STREAM_ERR 0x0002
154 /* The read/write limit has been exceeded. */
155 #define JAS_STREAM_RWLIMIT 0x0004
156 /* The error mask. */
157 #define JAS_STREAM_ERRMASK \
158  (JAS_STREAM_EOF | JAS_STREAM_ERR | JAS_STREAM_RWLIMIT)
159 
160 /*
161  * Other miscellaneous constants.
162  */
163 
164 /* The default buffer size (for fully-buffered operation). */
165 #define JAS_STREAM_BUFSIZE 8192
166 /* The default permission mask for file creation. */
167 #define JAS_STREAM_PERMS 0666
168 
169 /* The maximum number of characters that can always be put back on a stream. */
170 #define JAS_STREAM_MAXPUTBACK 16
171 
172 /******************************************************************************\
173 * Types.
174 \******************************************************************************/
175 
176 /*
177  * Generic file object.
178  */
179 
180 typedef void jas_stream_obj_t;
181 
182 /*
183  * Generic file object operations.
184  */
185 
186 typedef struct {
187 
188  /* Read characters from a file object. */
189  int (*read_)(jas_stream_obj_t *obj, char *buf, unsigned cnt);
190 
191  /* Write characters to a file object. */
192  int (*write_)(jas_stream_obj_t *obj, const char *buf, unsigned cnt);
193 
194  /* Set the position for a file object. */
195  long (*seek_)(jas_stream_obj_t *obj, long offset, int origin);
196 
197  /* Close a file object. */
198  int (*close_)(jas_stream_obj_t *obj);
199 
200 } jas_stream_ops_t;
201 
202 /*
203  * Stream object.
204  */
205 
206 typedef struct {
207 
208  /* The mode in which the stream was opened. */
209  int openmode_;
210 
211  /* The buffering mode. */
212  int bufmode_;
213 
214  /* The stream status. */
215  int flags_;
216 
217  /* The start of the buffer area to use for reading/writing. */
218  jas_uchar *bufbase_;
219 
220  /* The start of the buffer area excluding the extra initial space for
221  character putback. */
222  jas_uchar *bufstart_;
223 
224  /* The buffer size. */
225  int bufsize_;
226 
227  /* The current position in the buffer. */
228  jas_uchar *ptr_;
229 
230  /* The number of characters that must be read/written before
231  the buffer needs to be filled/flushed. */
232  int cnt_;
233 
234  /* A trivial buffer to be used for unbuffered operation. */
235  jas_uchar tinybuf_[JAS_STREAM_MAXPUTBACK + 1];
236 
237  /* The operations for the underlying stream file object. */
238  const jas_stream_ops_t *ops_;
239 
240  /* The underlying stream file object. */
241  jas_stream_obj_t *obj_;
242 
243  /* The number of characters read/written. */
244  long rwcnt_;
245 
246  /* The maximum number of characters that may be read/written. */
247  long rwlimit_;
248 
249 } jas_stream_t;
250 
251 /*
252  * Regular file object.
253  */
254 
255 /*
256  * File descriptor file object.
257  */
258 typedef struct {
259  int fd;
260  int flags;
261  char pathname[JAS_PATH_MAX + 1];
262 } jas_stream_fileobj_t;
263 
264 /* Delete underlying file object upon stream close. */
265 #define JAS_STREAM_FILEOBJ_DELONCLOSE 0x01
266 /* Do not close underlying file object upon stream close. */
267 #define JAS_STREAM_FILEOBJ_NOCLOSE 0x02
268 
269 /*
270  * Memory file object.
271  */
272 
273 typedef struct {
274 
275  /* The data associated with this file. */
276  jas_uchar *buf_;
277 
278  /* The allocated size of the buffer for holding file data. */
279  size_t bufsize_;
280 
281  /* The length of the file. */
282  uint_fast32_t len_;
283 
284  /* The seek position. */
285  uint_fast32_t pos_;
286 
287  /* Is the buffer growable? */
288  int growable_;
289 
290  /* Was the buffer allocated internally? */
291  int myalloc_;
292 
293 } jas_stream_memobj_t;
294 
295 /******************************************************************************\
296 * Macros/functions for opening and closing streams.
297 \******************************************************************************/
298 
313 JAS_DLLEXPORT
314 jas_stream_t *jas_stream_fopen(const char *filename, const char *mode);
315 
350 JAS_DLLEXPORT
351 jas_stream_t *jas_stream_memopen(char *buffer, int buffer_size);
352 
358 JAS_DLLEXPORT
359 jas_stream_t *jas_stream_memopen2(char *buffer, size_t buffer_size);
360 
375 JAS_DLLEXPORT
376 jas_stream_t *jas_stream_fdopen(int fd, const char *mode);
377 
400 JAS_DLLEXPORT
401 jas_stream_t *jas_stream_freopen(const char *path, const char *mode, FILE *fp);
402 
417 JAS_DLLEXPORT jas_stream_t *jas_stream_tmpfile(void);
418 
437 JAS_DLLEXPORT
438 int jas_stream_close(jas_stream_t *stream);
439 
440 /******************************************************************************\
441 * Macros/functions for getting/setting the stream state.
442 \******************************************************************************/
443 
454 #define jas_stream_eof(stream) \
455  (((stream)->flags_ & JAS_STREAM_EOF) != 0)
456 
467 #define jas_stream_error(stream) \
468  (((stream)->flags_ & JAS_STREAM_ERR) != 0)
469 
478 #define jas_stream_clearerr(stream) \
479  ((stream)->flags_ &= ~(JAS_STREAM_ERR | JAS_STREAM_EOF))
480 
491 #define jas_stream_getrwlimit(stream) \
492  (((const jas_stream_t *)(stream))->rwlimit_)
493 
508 JAS_DLLEXPORT long jas_stream_setrwlimit(jas_stream_t *stream, long rwlimit);
509 
520 #define jas_stream_getrwcount(stream) \
521  (((const jas_stream_t *)(stream))->rwcnt_)
522 
535 JAS_DLLEXPORT long jas_stream_setrwcount(jas_stream_t *stream, long rw_count);
536 
537 /******************************************************************************\
538 * Macros/functions for I/O.
539 \******************************************************************************/
540 
541 /* Read a character from a stream. */
542 #ifndef NDEBUG
547 #define jas_stream_getc(stream) jas_stream_getc_func(stream)
548 #else
549 #define jas_stream_getc(stream) jas_stream_getc_macro(stream)
550 #endif
551 
552 /* Write a character to a stream. */
553 #ifndef NDEBUG
558 #define jas_stream_putc(stream, c) jas_stream_putc_func(stream, c)
559 #else
560 #define jas_stream_putc(stream, c) jas_stream_putc_macro(stream, c)
561 #endif
562 
600 JAS_DLLEXPORT
601 unsigned jas_stream_read(jas_stream_t *stream, void *buffer, unsigned count);
602 
626 JAS_DLLEXPORT
627 unsigned jas_stream_peek(jas_stream_t *stream, void *buffer, size_t count);
628 
660 JAS_DLLEXPORT
661 unsigned jas_stream_write(jas_stream_t *stream, const void *buffer,
662  unsigned count);
663 
685 JAS_DLLEXPORT
686 int jas_stream_printf(jas_stream_t *stream, const char *format, ...);
687 
703 JAS_DLLEXPORT int jas_stream_puts(jas_stream_t *stream, const char *s);
704 
726 JAS_DLLEXPORT char *
727 jas_stream_gets(jas_stream_t *stream, char *buffer, int buffer_size);
728 
747 #define jas_stream_peekc(stream) \
748  (((stream)->cnt_ <= 0) ? jas_stream_fillbuf(stream, 0) : \
749  ((int)(*(stream)->ptr_)))
750 
774 JAS_DLLEXPORT int
775 jas_stream_ungetc(jas_stream_t *stream, int c);
776 
777 /******************************************************************************\
778 * Macros/functions for getting/setting the stream position.
779 \******************************************************************************/
780 
796 JAS_ATTRIBUTE_PURE JAS_DLLEXPORT
797 int jas_stream_isseekable(jas_stream_t *stream);
798 
818 JAS_DLLEXPORT
819 long jas_stream_seek(jas_stream_t *stream, long offset, int origin);
820 
833 JAS_ATTRIBUTE_PURE JAS_DLLEXPORT
834 long jas_stream_tell(jas_stream_t *stream);
835 
848 JAS_DLLEXPORT int jas_stream_rewind(jas_stream_t *stream);
849 
850 /******************************************************************************\
851 * Macros/functions for flushing.
852 \******************************************************************************/
853 
864 JAS_DLLEXPORT int jas_stream_flush(jas_stream_t *stream);
865 
866 /******************************************************************************\
867 * Miscellaneous macros/functions.
868 \******************************************************************************/
869 
890 JAS_DLLEXPORT int jas_stream_copy(jas_stream_t *destination, jas_stream_t *source, int count);
891 
914 JAS_DLLEXPORT
915 int jas_stream_display(jas_stream_t *stream, FILE *fp, int count);
916 
939 JAS_DLLEXPORT int jas_stream_gobble(jas_stream_t *stream, int count);
940 
965 JAS_DLLEXPORT int jas_stream_pad(jas_stream_t *stream, int count, int value);
966 
984 JAS_ATTRIBUTE_PURE JAS_DLLEXPORT
985 long jas_stream_length(jas_stream_t *stream);
986 
987 /******************************************************************************\
988 * Internal functions.
989 \******************************************************************************/
990 
991 /* The following functions are for internal use only! If you call them
992 directly, you will die a horrible, miserable, and painful death! */
993 
994 /* These prototypes need to be here for the sake of the stream_getc and
995 stream_putc macros. */
996 /* Library users must not invoke these functions directly. */
997 JAS_DLLEXPORT int jas_stream_fillbuf(jas_stream_t *stream, int getflag);
998 JAS_DLLEXPORT int jas_stream_flushbuf(jas_stream_t *stream, int c);
999 JAS_DLLEXPORT int jas_stream_getc_func(jas_stream_t *stream);
1000 JAS_DLLEXPORT int jas_stream_putc_func(jas_stream_t *stream, int c);
1001 
1002 /* Read a character from a stream. */
1003 static inline int jas_stream_getc2(jas_stream_t *stream)
1004 {
1005  if (--stream->cnt_ < 0)
1006  return jas_stream_fillbuf(stream, 1);
1007 
1008  ++stream->rwcnt_;
1009  return (int)(*stream->ptr_++);
1010 }
1011 
1012 static inline int jas_stream_getc_macro(jas_stream_t *stream)
1013 {
1014  if (stream->flags_ & (JAS_STREAM_ERR | JAS_STREAM_EOF | JAS_STREAM_RWLIMIT))
1015  return EOF;
1016 
1017  if (stream->rwlimit_ >= 0 && stream->rwcnt_ >= stream->rwlimit_) {
1018  stream->flags_ |= JAS_STREAM_RWLIMIT;
1019  return EOF;
1020  }
1021 
1022  return jas_stream_getc2(stream);
1023 }
1024 
1025 /* Write a character to a stream. */
1026 static inline int jas_stream_putc2(jas_stream_t *stream, jas_uchar c)
1027 {
1028  stream->bufmode_ |= JAS_STREAM_WRBUF;
1029 
1030  if (--stream->cnt_ < 0)
1031  return jas_stream_flushbuf(stream, c);
1032  else {
1033  ++stream->rwcnt_;
1034  return (int)(*stream->ptr_++ = c);
1035  }
1036 }
1037 
1038 static inline int jas_stream_putc_macro(jas_stream_t *stream, jas_uchar c)
1039 {
1040  if (stream->flags_ & (JAS_STREAM_ERR | JAS_STREAM_EOF | JAS_STREAM_RWLIMIT))
1041  return EOF;
1042 
1043  if (stream->rwlimit_ >= 0 && stream->rwcnt_ >= stream->rwlimit_) {
1044  stream->flags_ |= JAS_STREAM_RWLIMIT;
1045  return EOF;
1046  }
1047 
1048  return jas_stream_putc2(stream, c);
1049 }
1050 
1055 #ifdef __cplusplus
1056 }
1057 #endif
1058 
1059 #endif
JAS_DLLEXPORT int jas_stream_flush(jas_stream_t *stream)
Flush any pending output to a stream.
Definition: jas_stream.c:1001
JAS_DLLEXPORT int jas_stream_pad(jas_stream_t *stream, int count, int value)
Write a fill character multiple times to a stream.
Definition: jas_stream.c:850
JAS_DLLEXPORT unsigned jas_stream_peek(jas_stream_t *stream, void *buffer, size_t count)
Attempt to retrieve one or more pending characters of input from a stream into a buffer without actua...
Definition: jas_stream.c:720
JAS_DLLEXPORT long jas_stream_seek(jas_stream_t *stream, long offset, int origin)
Set the current position within the stream.
Definition: jas_stream.c:891
JAS_ATTRIBUTE_PURE JAS_DLLEXPORT long jas_stream_tell(jas_stream_t *stream)
Get the current position within the stream.
Definition: jas_stream.c:926
JAS_DLLEXPORT char * jas_stream_gets(jas_stream_t *stream, char *buffer, int buffer_size)
Read a line of input from a stream.
Definition: jas_stream.c:807
JAS_ATTRIBUTE_PURE JAS_DLLEXPORT int jas_stream_isseekable(jas_stream_t *stream)
Determine if stream supports seeking.
Definition: jas_stream.c:871
JAS_DLLEXPORT jas_stream_t * jas_stream_tmpfile(void)
Open a temporary file as a stream.
Definition: jas_stream.c:490
JAS_DLLEXPORT int jas_stream_printf(jas_stream_t *stream, const char *format,...)
Write formatted output to a stream.
Definition: jas_stream.c:781
JAS_DLLEXPORT int jas_stream_ungetc(jas_stream_t *stream, int c)
Put a character back on a stream.
Definition: jas_stream.c:652
JAS_DLLEXPORT int jas_stream_puts(jas_stream_t *stream, const char *s)
Write a string to a stream.
Definition: jas_stream.c:794
JAS_DLLEXPORT jas_stream_t * jas_stream_memopen(char *buffer, int buffer_size)
Open a memory buffer as a stream.
Definition: jas_stream.c:276
JAS_DLLEXPORT jas_stream_t * jas_stream_fopen(const char *filename, const char *mode)
Open a file as a stream.
Definition: jas_stream.c:301
JAS_DLLEXPORT unsigned jas_stream_write(jas_stream_t *stream, const void *buffer, unsigned count)
Write characters from a buffer to a stream.
Definition: jas_stream.c:735
JAS_DLLEXPORT jas_stream_t * jas_stream_freopen(const char *path, const char *mode, FILE *fp)
Open a stdio (i.e., C standard library) stream as a stream.
Definition: jas_stream.c:368
JAS_ATTRIBUTE_PURE JAS_DLLEXPORT long jas_stream_length(jas_stream_t *stream)
Get the size of the file associated with the specified stream.
Definition: jas_stream.c:1225
JAS_DLLEXPORT long jas_stream_setrwlimit(jas_stream_t *stream, long rwlimit)
Set the read/write limit for a stream.
Definition: jas_stream.c:1164
JAS_DLLEXPORT jas_stream_t * jas_stream_memopen2(char *buffer, size_t buffer_size)
Definition: jas_stream.c:189
JAS_DLLEXPORT int jas_stream_gobble(jas_stream_t *stream, int count)
Consume (i.e., discard) characters from stream.
Definition: jas_stream.c:831
JAS_DLLEXPORT int jas_stream_close(jas_stream_t *stream)
Close a stream.
Definition: jas_stream.c:610
JAS_DLLEXPORT unsigned jas_stream_read(jas_stream_t *stream, void *buffer, unsigned count)
Read characters from a stream into a buffer.
Definition: jas_stream.c:670
JAS_DLLEXPORT jas_stream_t * jas_stream_fdopen(int fd, const char *mode)
Open a file descriptor as a stream.
Definition: jas_stream.c:540
JAS_DLLEXPORT long jas_stream_setrwcount(jas_stream_t *stream, long rw_count)
Set the read/write count for a stream.
Definition: jas_stream.c:1154
JAS_DLLEXPORT int jas_stream_rewind(jas_stream_t *stream)
Seek to the beginning of a stream.
Definition: jas_stream.c:885
JAS_DLLEXPORT int jas_stream_display(jas_stream_t *stream, FILE *fp, int count)
Print a hex dump of data read from a stream.
Definition: jas_stream.c:1174
JAS_DLLEXPORT int jas_stream_copy(jas_stream_t *destination, jas_stream_t *source, int count)
Copy data from one stream to another.
Definition: jas_stream.c:1129
Primitive Types.