lib/libc/stdio/priv_stdio.h

   1 /*-
   2  * Copyright (c) 1990, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 2005 Joerg Sonnenberger <joerg@bec.de>.  All rights reserved.
   5  *
   6  * This code is derived from software contributed to Berkeley by
   7  * Chris Torek.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * $DragonFly: src/lib/libc/stdio/priv_stdio.h,v 1.3 2005/08/02 00:44:39 joerg Exp $
  34  */
  35
  36 #ifndef _LIBC_PRIV_STDIO_H_
  37 #define _LIBC_PRIV_STDIO_H_
  38
  39 #include <pthread.h>
  40
  41 #include "wcio.h"
  42
  43 /*
  44  * NB: to fit things in six character monocase externals, the stdio
  45  * code uses the prefix `__s' for stdio objects, typically followed
  46  * by a three-character attempt at a mnemonic.
  47  */
  48
  49 /* stdio buffers */
  50 struct __sbuf {
  51         unsigned char *_base;
  52         int     _size;
  53 };
  54
  55 /*
  56  * _ub, _up, and _ur are used when ungetc() pushes back more characters
  57  * than fit in the current _bf, or when ungetc() pushes back a character
  58  * that does not match the previous one in _bf.  When this happens,
  59  * _ub._base becomes non-nil (i.e., a stream has ungetc() data iff
  60  * _ub._base!=NULL) and _up and _ur save the current values of _p and _r.
  61  */
  62
  63 struct __FILE {
  64         struct __FILE_public    pub;
  65         struct  __sbuf _bf;     /* the buffer (at least 1 byte, if !NULL) */
  66
  67         /* operations */
  68         void    *_cookie;       /* cookie passed to io functions */
  69         int     (*_close)(void *);
  70         int     (*_read)(void *, char *, int);
  71         fpos_t  (*_seek)(void *, fpos_t, int);
  72         int     (*_write)(void *, const char *, int);
  73
  74         /* separate buffer for long sequences of ungetc() */
  75         struct  __sbuf _ub;     /* ungetc buffer */
  76         int     _ur;            /* saved _r when _r is counting ungetc data */
  77
  78         /* tricks to meet minimum requirements even when malloc() fails */
  79         unsigned char _ubuf[3]; /* guarantee an ungetc() buffer */
  80         unsigned char _nbuf[1]; /* guarantee a getc() buffer */
  81
  82         /* separate buffer for fgetln() when line crosses buffer boundary */
  83         struct  __sbuf _lb;     /* buffer for fgetln() */
  84
  85         /* Unix stdio files get aligned to block boundaries on fseek() */
  86         int     _blksize;       /* stat.st_blksize (may be != _bf._size) */
  87         fpos_t  _offset;        /* current lseek offset (see WARNING) */
  88
  89         unsigned char   *_up;   /* saved _p when _p is doing ungetc data */
  90         pthread_mutex_t _fl_mutex;      /* used for MT-safety */
  91         pthread_t       _fl_owner;      /* current owner */
  92         int             _fl_count;      /* recursive lock count */
  93
  94         struct wchar_io_data _wcio;
  95 };
  96
  97 /*
  98  * I/O descriptors for __sfvwrite().
  99  */
 100 struct __siov {
 101         void    *iov_base;
 102         size_t  iov_len;
 103 };
 104 struct __suio {
 105         struct  __siov *uio_iov;
 106         int     uio_iovcnt;
 107         int     uio_resid;
 108 };
 109
 110 /*
 111  * The first few FILEs are statically allocated; others are dynamically
 112  * allocated and linked in via this glue structure.
 113  */
 114 struct glue {
 115         struct  glue *next;
 116         int     niobs;
 117         FILE    *iobs;
 118 };
 119
 120 extern struct glue __sglue;
 121
 122 __BEGIN_DECLS
 123 int     __sfvwrite(FILE *, struct __suio *);
 124 int     __fflush(FILE *);
 125 int     __ungetc(int, FILE *);
 126 __END_DECLS
 127
 128 #endif /* _LIBC_PRIV_STDIO_H_ */