usr/src/lib/libast/common/port/astquery.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                   Phong Vo <kpv@research.att.com>                    *
  20 *                                                                      *
  21 ***********************************************************************/
  22 #pragma prototyped
  23 /*
  24  * AT&T Research
  25  *
  26  * output printf prompt and read response
  27  * if format==0 then verify that interaction is possible
  28  *
  29  * return:
  30  *
  31  *      0       [1yY+]
  32  *      -1      [qQ] or EOF
  33  *      1       otherwise
  34  *
  35  * if (quit&ERROR_PROMPT) then tty forced for IO
  36  * if quit>=0 then [qQ] or EOF calls exit(quit)
  37  */
  38
  39 #include <ast.h>
  40 #include <error.h>
  41
  42 int
  43 astquery(int quit, const char* format, ...)
  44 {
  45         va_list         ap;
  46         register int    n;
  47         register int    c;
  48         Sfio_t*         ip;
  49         Sfio_t*         op;
  50
  51         static Sfio_t*  rfp;
  52         static Sfio_t*  wfp;
  53
  54         va_start(ap, format);
  55         if (!format)
  56                 return 0;
  57         if (!rfp)
  58         {
  59                 c = errno;
  60                 if (isatty(sffileno(sfstdin)))
  61                         rfp = sfstdin;
  62                 else if (!(rfp = sfopen(NiL, "/dev/tty", "r")))
  63                         return -1;
  64                 if (isatty(sffileno(sfstderr)))
  65                         wfp = sfstderr;
  66                 else if (!(wfp = sfopen(NiL, "/dev/tty", "w")))
  67                         return -1;
  68                 errno = c;
  69         }
  70         if (quit & ERROR_PROMPT)
  71         {
  72                 quit &= ~ERROR_PROMPT;
  73                 ip = rfp;
  74                 op = wfp;
  75         }
  76         else
  77         {
  78                 ip = sfstdin;
  79                 op = sfstderr;
  80         }
  81         sfsync(sfstdout);
  82         sfvprintf(op, format, ap);
  83         sfsync(op);
  84         for (n = c = sfgetc(ip);; c = sfgetc(ip))
  85                 switch (c)
  86                 {
  87                 case EOF:
  88                         n = c;
  89                         /*FALLTHROUGH*/
  90                 case '\n':
  91                         switch (n)
  92                         {
  93                         case EOF:
  94                         case 'q':
  95                         case 'Q':
  96                                 if (quit >= 0)
  97                                         exit(quit);
  98                                 return -1;
  99                         case '1':
 100                         case 'y':
 101                         case 'Y':
 102                         case '+':
 103                                 return 0;
 104                         }
 105                         return 1;
 106                 }
 107         va_end(ap);
 108         /*NOTREACHED*/
 109 }