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Diff for /gforth/engine/io.c between versions 1.32 and 1.36

version 1.32, 2007/12/31 18:40:25 version 1.36, 2009/06/29 20:21:28
Line 1 Line 1
 /* direct key io driver  /* direct key io driver
   
   Copyright (C) 1995,1996,1997,1998,1999,2002,2003,2006,2007 Free Software Foundation, Inc.    Copyright (C) 1995,1996,1997,1998,1999,2002,2003,2006,2007,2008 Free Software Foundation, Inc.
   
   This file is part of Gforth.    This file is part of Gforth.
   
Line 39 Line 39
 typedef unsigned int uint32_t;  typedef unsigned int uint32_t;
 #endif  #endif
   
   #include <stdlib.h>
 #include <stdio.h>  #include <stdio.h>
 #include <signal.h>  #include <signal.h>
 #include <string.h>  #include <string.h>
Line 617  void deprep_terminal () Line 618  void deprep_terminal ()
 }  }
 #endif  /* NEW_TTY_DRIVER */  #endif  /* NEW_TTY_DRIVER */
   
 long key_avail (FILE * stream)  /* an ungetc() variant where we can know that there is a character waiting:
      gf_ungetc: like ungetc
      gf_regetc: call when reading a char, but does not get the character
      gf_ungottenc: true if there is a char waiting
   
      Implementation: just an array containing all the FILEs with ungotten chars.
      Sequential search for membership checking (there should not be many elements)
   */
   
   static FILE **ungotten_files = NULL;
   static size_t n_ungotten = 0; /* actual number */
   static size_t max_ungotten = 0; /* buffer size */
   
   int gf_ungetc(int c, FILE *stream)
   /* like ungetc, but works with the others */
   {
     if (n_ungotten>=max_ungotten) {
       max_ungotten = max_ungotten*2+1;
       ungotten_files = realloc(ungotten_files, max_ungotten*sizeof(FILE *));
     }
     ungotten_files[n_ungotten++] = stream;
     return ungetc(c, stream);
   }
   
   static long search_ungotten(FILE *stream)
   {
     long i;
     for (i=0; i<n_ungotten; i++)
       if (ungotten_files[i] == stream)
         return i;
     return -1;
   }
   
   void gf_regetc(FILE *stream)
   /* remove STREAM from ungotten_files */
   {
     long i = search_ungotten(stream);
     if (i>=0)
       ungotten_files[i] = ungotten_files[--n_ungotten];
   }
   
   int gf_ungottenc(FILE *stream)
   /* true if stream has been ungotten */
   {
     return search_ungotten(stream)>=0;
   }
   
   long key_avail (FILE *stream)
 {  {
   int tty = fileno (stream);    int tty = fileno (stream);
   fd_set selin;    fd_set selin;
   static struct timespec now = { 0 , 0 };    static struct timeval now = { 0 , 0 };
   int res;    int chars_avail;
   
   setvbuf(stream, NULL, _IONBF, 0);    setvbuf(stream, NULL, _IONBF, 0);
   if(!terminal_prepped && stream == stdin)    if(!terminal_prepped && stream == stdin)
     prep_terminal();      prep_terminal();
     if (gf_ungottenc(stream))
       return 1;
   
   FD_ZERO(&selin);    FD_ZERO(&selin);
   FD_SET(tty, &selin);    FD_SET(tty, &selin);
   return select(1, &selin, NULL, NULL, &now);    chars_avail = select(1, &selin, NULL, NULL, &now);
     if (chars_avail > 0) {
       /* getc won't block */
       int c = getc(stream);
       if (c==EOF)
         return 0;
       gf_ungetc(c, stream);
     }
     return (chars_avail == -1) ? 0 : chars_avail;
 }  }
   
 /* Get a key from the buffer of characters to be read.  /* Get a key from the buffer of characters to be read.
Removed from v.1.32  
changed lines
  Added in v.1.36

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