src/input.h

   1 /*-
   2  * Copyright (c) 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 1997-2005
   5  *      Herbert Xu <herbert@gondor.apana.org.au>.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Kenneth Almquist.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  *      @(#)input.h     8.2 (Berkeley) 5/4/95
  35  */
  36
  37 #include <limits.h>
  38 #include <stdbool.h>
  39
  40 #ifdef SMALL
  41 #define IS_DEFINED_SMALL 1
  42 #else
  43 #define IS_DEFINED_SMALL 0
  44 #endif
  45
  46 #define PUNGETC_MAX (MB_LEN_MAX > 16 ? MB_LEN_MAX : 16)
  47
  48 /* PEOF (the end of file marker) is defined in syntax.h */
  49 #define PEOA ((PEOF) - 1)
  50
  51 enum {
  52         INPUT_PUSH_FILE = 1,
  53         INPUT_NOFILE_OK = 2,
  54 };
  55
  56 struct alias;
  57
  58 struct strpush {
  59         struct strpush *prev;   /* preceding string on stack */
  60         char *prevstring;
  61         int prevnleft;
  62         struct alias *ap;       /* if push was associated with an alias */
  63         char *string;           /* remember the string since it may change */
  64
  65         /* Delay freeing so we can stop nested aliases. */
  66         struct strpush *spfree;
  67
  68         /* Number of outstanding calls to pungetc. */
  69         int unget;
  70 };
  71
  72 /*
  73  * The parsefile structure pointed to by the global variable parsefile
  74  * contains information about the current file being read.
  75  */
  76
  77 struct parsefile {
  78         struct parsefile *prev; /* preceding file on stack */
  79         int linno;              /* current line */
  80         int fd;                 /* file descriptor (or -1 if string) */
  81         int nleft;              /* number of chars left in this line */
  82 #ifndef SMALL
  83         int lleft;              /* number of chars left in this buffer */
  84 #endif
  85         char *nextc;            /* next char in buffer */
  86         char *buf;              /* input buffer */
  87         struct strpush *strpush; /* for pushing strings at this level */
  88         struct strpush basestrpush; /* so pushing one is fast */
  89
  90         /* Delay freeing so we can stop nested aliases. */
  91         struct strpush *spfree;
  92
  93         /* Number of outstanding calls to pungetc. */
  94         int unget;
  95 };
  96
  97 extern struct parsefile *parsefile;
  98 extern int stdin_istty;
  99
 100 /*
 101  * The input line number.  Input.c just defines this variable, and saves
 102  * and restores it when files are pushed and popped.  The user of this
 103  * package must set its value.
 104  */
 105 #define plinno (parsefile->linno)
 106
 107 int pgetc(void);
 108 int pgetc_eoa(void);
 109 void pungetc(void);
 110 void pungetn(int);
 111 void pushstring(char *, void *);
 112 int setinputfile(const char *, int);
 113 void setinputstring(char *);
 114 void pushstdin(void);
 115 void popfile(void);
 116 void unwindfiles(struct parsefile *);
 117 void popallfiles(void);
 118 void flush_input(void);
 119 void reset_input(void);
 120
 121 static inline int input_get_lleft(struct parsefile *pf)
 122 {
 123 #ifdef SMALL
 124         return 0;
 125 #else
 126         return pf->lleft;
 127 #endif
 128 }
 129
 130 static inline void input_set_lleft(struct parsefile *pf, int len)
 131 {
 132 #ifndef SMALL
 133         pf->lleft = len;
 134 #endif
 135 }