1 /*        $NetBSD: output.c,v 1.8 2009/01/24 13:58:21 tsutsui Exp $   */
2 
3 /*
4  * Copyright (c) 1988 Mark Nudelman
5  * Copyright (c) 1988, 1993
6  *        The Regents of the University of California.  All rights reserved.
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 #include <sys/cdefs.h>
34 #ifndef lint
35 #if 0
36 static char sccsid[] = "@(#)output.c    8.2 (Berkeley) 4/27/95";
37 #else
38 __RCSID("$NetBSD: output.c,v 1.8 2009/01/24 13:58:21 tsutsui Exp $");
39 #endif
40 #endif /* not lint */
41 
42 /*
43  * High level routines dealing with the output to the screen.
44  */
45 
46 #include <stdio.h>
47 #include <string.h>
48 #include <unistd.h>
49 #include <stdlib.h>
50 
51 #include "less.h"
52 #include "extern.h"
53 
54 int errmsgs;        /* Count of messages displayed by error() */
55 
56 /* display the line which is in the line buffer. */
57 void
put_line()58 put_line()
59 {
60           char *p;
61           int c;
62           int column;
63 
64           if (sigs)
65           {
66                     /*
67                      * Don't output if a signal is pending.
68                      */
69                     screen_trashed = 1;
70                     return;
71           }
72 
73           if (line == NULL)
74                     line = "";
75 
76           column = 0;
77           for (p = line;  *p != '\0';  p++)
78           {
79                     switch (c = *p)
80                     {
81                     case UL_CHAR:
82                               ul_enter();
83                               column += ul_width +1;
84                               break;
85                     case UE_CHAR:
86                               ul_exit();
87                               column += ue_width;
88                               break;
89                     case BO_CHAR:
90                               bo_enter();
91                               column += bo_width +1;
92                               break;
93                     case BE_CHAR:
94                               bo_exit();
95                               column += be_width;
96                               break;
97                     case '\t':
98                               do
99                               {
100                                         putchr(' ');
101                                         column++;
102                               } while ((column % tabstop) != 0);
103                               break;
104                     case '\b':
105                               putbs();
106                               column--;
107                               break;
108                     default:
109                               if (c & 0200)
110                               {
111                                         /*
112                                          * Control characters arrive here as the
113                                          * normal character [CARAT_CHAR(c)] with
114                                          * the 0200 bit set.  See pappend().
115                                          */
116                                         putchr('^');
117                                         putchr(c & 0177);
118                                         column += 2;
119                               } else
120                               {
121                                         putchr(c);
122                                         column++;
123                               }
124                     }
125           }
126           if (column < sc_width || !auto_wrap || ignaw)
127                     putchr('\n');
128 }
129 
130 static char obuf[1024];
131 static char *ob = obuf;
132 
133 /*
134  * Flush buffered output.
135  */
136 void
flush()137 flush()
138 {
139           int n;
140 
141           n = ob - obuf;
142           if (n == 0)
143                     return;
144           if (write(1, obuf, n) != n)
145                     screen_trashed = 1;
146           ob = obuf;
147 }
148 
149 /*
150  * Purge any pending output.
151  */
152 void
purge()153 purge()
154 {
155 
156           ob = obuf;
157 }
158 
159 /*
160  * Output a character.
161  */
162 int
putchr(c)163 putchr(c)
164           int c;
165 {
166           if (ob >= &obuf[sizeof(obuf)])
167                     flush();
168           *ob++ = c;
169           return c;
170 }
171 
172 /*
173  * Output a string.
174  */
175 void
putstr(s)176 putstr(s)
177           char *s;
178 {
179           while (*s != '\0')
180                     putchr(*s++);
181 }
182 
183 int cmdstack;
184 static char return_to_continue[] = "(press RETURN)";
185 
186 /*
187  * Output a message in the lower left corner of the screen
188  * and wait for carriage return.
189  */
190 void
error(s)191 error(s)
192           char *s;
193 {
194           int ch;
195 
196           ++errmsgs;
197           if (!any_display) {
198                     /*
199                      * Nothing has been displayed yet.  Output this message on
200                      * error output (file descriptor 2) and don't wait for a
201                      * keystroke to continue.
202                      *
203                      * This has the desirable effect of producing all error
204                      * messages on error output if standard output is directed
205                      * to a file.  It also does the same if we never produce
206                      * any real output; for example, if the input file(s) cannot
207                      * be opened.  If we do eventually produce output, code in
208                      * edit() makes sure these messages can be seen before they
209                      * are overwritten or scrolled away.
210                      */
211                     if (s != NULL) {
212                               (void)write(2, s, strlen(s));
213                               (void)write(2, "\n", 1);
214                     }
215                     return;
216           }
217 
218           lower_left();
219           clear_eol();
220           so_enter();
221           if (s != NULL) {
222                     putstr(s);
223                     putstr("  ");
224           }
225           putstr(return_to_continue);
226           so_exit();
227 
228           if ((ch = getchr()) != '\n') {
229                     if (ch == 'q')
230                               quit();
231                     cmdstack = ch;
232           }
233           lower_left();
234 
235           if ((s != NULL ? strlen(s) : 0) + sizeof(return_to_continue) +
236                     so_width + se_width + 1 > sc_width)
237                     /*
238                      * Printing the message has probably scrolled the screen.
239                      * {{ Unless the terminal doesn't have auto margins,
240                      *    in which case we just hammered on the right margin. }}
241                      */
242                     repaint();
243           flush();
244 }
245 
246 static char intr_to_abort[] = "... (interrupt to abort)";
247 
248 void
ierror(s)249 ierror(s)
250           char *s;
251 {
252           lower_left();
253           clear_eol();
254           so_enter();
255           putstr(s);
256           putstr(intr_to_abort);
257           so_exit();
258           flush();
259 }
260