apps/plugins/frotz/buffer.c

   1 /* buffer.c - Text buffering and word wrapping
   2  *      Copyright (c) 1995-1997 Stefan Jokisch
   3  *
   4  * This file is part of Frotz.
   5  *
   6  * Frotz is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * Frotz is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  19  */
  20
  21 #include "frotz.h"
  22
  23 extern void stream_char (zchar);
  24 extern void stream_word (const zchar *);
  25 extern void stream_new_line (void);
  26
  27 static zchar buffer[TEXT_BUFFER_SIZE];
  28 static int bufpos = 0;
  29
  30 static zchar prev_c = 0;
  31
  32 /*
  33  * flush_buffer
  34  *
  35  * Copy the contents of the text buffer to the output streams.
  36  *
  37  */
  38
  39 void flush_buffer (void)
  40 {
  41     static bool locked = FALSE;
  42
  43     /* Make sure we stop when flush_buffer is called from flush_buffer.
  44        Note that this is difficult to avoid as we might print a newline
  45        during flush_buffer, which might cause a newline interrupt, that
  46        might execute any arbitrary opcode, which might flush the buffer. */
  47
  48     if (locked || bufpos == 0)
  49         return;
  50
  51     /* Send the buffer to the output streams */
  52
  53     buffer[bufpos] = 0;
  54
  55
  56     locked = TRUE;
  57
  58     stream_word (buffer);
  59
  60 #ifdef SPEECH_OUTPUT
  61     os_speech_output(buffer);
  62 #endif
  63
  64     locked = FALSE;
  65
  66     /* Reset the buffer */
  67
  68     bufpos = 0;
  69     prev_c = 0;
  70
  71 }/* flush_buffer */
  72
  73 /*
  74  * print_char
  75  *
  76  * High level output function.
  77  *
  78  */
  79
  80 void print_char (zchar c)
  81 {
  82     static bool flag = FALSE;
  83
  84     if (message || ostream_memory || enable_buffering) {
  85
  86         if (!flag) {
  87
  88             /* Characters 0 and ZC_RETURN are special cases */
  89
  90             if (c == ZC_RETURN)
  91                 { new_line (); return; }
  92             if (c == 0)
  93                 return;
  94
  95             /* Flush the buffer before a whitespace or after a hyphen */
  96
  97             if (c == ' ' || c == ZC_INDENT || c == ZC_GAP || (prev_c == '-' && c != '-'))
  98
  99
 100                 flush_buffer ();
 101
 102             /* Set the flag if this is part one of a style or font change */
 103
 104             if (c == ZC_NEW_FONT || c == ZC_NEW_STYLE)
 105                 flag = TRUE;
 106
 107             /* Remember the current character code */
 108
 109             prev_c = c;
 110
 111         } else flag = FALSE;
 112
 113         /* Insert the character into the buffer */
 114
 115         buffer[bufpos++] = c;
 116
 117         if (bufpos == TEXT_BUFFER_SIZE)
 118             runtime_error (ERR_TEXT_BUF_OVF);
 119
 120     } else stream_char (c);
 121
 122 }/* print_char */
 123
 124 /*
 125  * new_line
 126  *
 127  * High level newline function.
 128  *
 129  */
 130
 131 void new_line (void)
 132 {
 133
 134     flush_buffer (); stream_new_line ();
 135
 136 }/* new_line */
 137
 138
 139 /*
 140  * init_buffer
 141  *
 142  * Initialize buffer variables.
 143  *
 144  */
 145
 146 void init_buffer(void)
 147 {
 148     memset(buffer, 0, sizeof (zchar) * TEXT_BUFFER_SIZE);
 149     bufpos = 0;
 150     prev_c = 0;
 151 }
 152