snprintf/various.h

   1 /*-
   2  * Copyright (c) 1990 The Regents of the University of California.
   3  * All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Chris Torek.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #ifndef UST_SNPRINTF_VARIOUS_H
  34 #define UST_SNPRINTF_VARIOUS_H
  35
  36 #include <stdarg.h>
  37 #include <stddef.h>
  38 #include <stdio.h>
  39 #include <wchar.h>
  40
  41 struct __lttng_ust_sbuf {
  42         unsigned char *_base;
  43         int     _size;
  44 };
  45
  46 /*
  47  * stdio state variables.
  48  *
  49  * The following always hold:
  50  *
  51  *      if (_flags&(__SLBF|__SWR)) == (__SLBF|__SWR),
  52  *              _lbfsize is -_bf._size, else _lbfsize is 0
  53  *      if _flags&__SRD, _w is 0
  54  *      if _flags&__SWR, _r is 0
  55  *
  56  * This ensures that the getc and putc macros (or inline functions) never
  57  * try to write or read from a file that is in `read' or `write' mode.
  58  * (Moreover, they can, and do, automatically switch from read mode to
  59  * write mode, and back, on "r+" and "w+" files.)
  60  *
  61  * _lbfsize is used only to make the inline line-buffered output stream
  62  * code as compact as possible.
  63  *
  64  * _ub, _up, and _ur are used when ungetc() pushes back more characters
  65  * than fit in the current _bf, or when ungetc() pushes back a character
  66  * that does not match the previous one in _bf.  When this happens,
  67  * _ub._base becomes non-nil (i.e., a stream has ungetc() data iff
  68  * _ub._base!=NULL) and _up and _ur save the current values of _p and _r.
  69  */
  70 typedef struct __lttng_ust_sFILE {
  71         unsigned char *_p;      /* current position in (some) buffer */
  72         int     _r;             /* read space left for getc() */
  73         int     _w;             /* write space left for putc() */
  74         short   _flags;         /* flags, below; this FILE is free if 0 */
  75         short   _file;          /* fileno, if Unix descriptor, else -1 */
  76         struct  __lttng_ust_sbuf _bf;     /* the buffer (at least 1 byte, if !NULL) */
  77         int     _lbfsize;       /* 0 or -_bf._size, for inline putc */
  78
  79         /* operations */
  80         void    *_cookie;       /* cookie passed to io functions */
  81         int     (*_close)(void *);
  82         int     (*_read)(void *, char *, int);
  83         fpos_t  (*_seek)(void *, fpos_t, int);
  84         int     (*_write)(void *, const char *, int);
  85
  86         /* extension data, to avoid further ABI breakage */
  87         struct  __lttng_ust_sbuf _ext;
  88         /* data for long sequences of ungetc() */
  89         unsigned char *_up;     /* saved _p when _p is doing ungetc data */
  90         int     _ur;            /* saved _r when _r is counting ungetc data */
  91
  92         /* tricks to meet minimum requirements even when malloc() fails */
  93         unsigned char _ubuf[3]; /* guarantee an ungetc() buffer */
  94         unsigned char _nbuf[1]; /* guarantee a getc() buffer */
  95
  96         /* separate buffer for fgetln() when line crosses buffer boundary */
  97         struct  __lttng_ust_sbuf _lb;     /* buffer for fgetln() */
  98
  99         /* Unix stdio files get aligned to block boundaries on fseek() */
 100         int     _blksize;       /* stat.st_blksize (may be != _bf._size) */
 101         fpos_t  _offset;        /* current lseek offset */
 102 } LTTNG_UST_LFILE;
 103
 104 #define __SLBF  0x0001          /* line buffered */
 105 #define __SNBF  0x0002          /* unbuffered */
 106 #define __SRD   0x0004          /* OK to read */
 107 #define __SWR   0x0008          /* OK to write */
 108         /* RD and WR are never simultaneously asserted */
 109 #define __SRW   0x0010          /* open for reading & writing */
 110 #define __SEOF  0x0020          /* found EOF */
 111 #define __SERR  0x0040          /* found error */
 112 #define __SMBF  0x0080          /* _buf is from malloc */
 113 #define __SAPP  0x0100          /* fdopen()ed in append mode */
 114 #define __SSTR  0x0200          /* this is an sprintf/snprintf string */
 115 #define __SOPT  0x0400          /* do fseek() optimisation */
 116 #define __SNPT  0x0800          /* do not do fseek() optimisation */
 117 #define __SOFF  0x1000          /* set iff _offset is in fact correct */
 118 #define __SMOD  0x2000          /* true => fgetln modified _p text */
 119 #define __SALC  0x4000          /* allocate string space dynamically */
 120
 121 #define __sferror(p)    (((p)->_flags & __SERR) != 0)
 122
 123 extern int ust_safe_fflush(LTTNG_UST_LFILE *fp);
 124 extern int ust_safe_vfprintf(LTTNG_UST_LFILE *fp, const char *fmt0, va_list ap);
 125
 126 extern size_t ust_safe_mbrtowc(wchar_t *pwc, const char *s, size_t n, mbstate_t *ps);
 127
 128 #endif /* UST_SNPRINTF_VARIOUS_H */