1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
/*-
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* Simple paged-output and paged-viewing functions
*/
#include "stand.h"
#include <string.h>
static int p_maxlines = -1;
static int p_freelines;
static char *pager_prompt1 = " --more-- <space> page down <enter> line down <q> quit ";
static char *pager_blank = " ";
/*
* 'open' the pager
*/
void
pager_open(void)
{
int nlines;
char *cp, *lp;
nlines = 24; /* sensible default */
if ((cp = getenv("LINES")) != NULL) {
nlines = strtol(cp, &lp, 0);
}
p_maxlines = nlines - 1;
if (p_maxlines < 1)
p_maxlines = 1;
p_freelines = p_maxlines;
}
/*
* 'close' the pager
*/
void
pager_close(void)
{
p_maxlines = -1;
}
/*
* Emit lines to the pager; may not return until the user
* has responded to the prompt.
*
* Will return nonzero if the user enters 'q' or 'Q' at the prompt.
*
* XXX note that this watches outgoing newlines (and eats them), but
* does not handle wrap detection (req. count of columns).
*/
int
pager_output(const char *cp)
{
int action;
if (cp == NULL)
return(0);
for (;;) {
if (*cp == 0)
return(0);
putchar(*cp); /* always emit character */
if (*(cp++) == '\n') { /* got a newline? */
p_freelines--;
if (p_freelines <= 0) {
printf(pager_prompt1);
action = 0;
while (action == 0) {
switch(getchar()) {
case '\r':
case '\n':
p_freelines = 1;
action = 1;
break;
case ' ':
p_freelines = p_maxlines;
action = 1;
break;
case 'q':
case 'Q':
action = 2;
break;
default:
break;
}
}
printf("\r%s\r", pager_blank);
if (action == 2)
return(1);
}
}
}
}
/*
* Display from (fd).
*/
int
pager_file(const char *fname)
{
char buf[80];
size_t hmuch;
int fd;
int result;
if ((fd = open(fname, O_RDONLY)) == -1) {
printf("can't open '%s': %s\n", fname, strerror(errno));
return(-1);
}
for (;;) {
hmuch = read(fd, buf, sizeof(buf) - 1);
if (hmuch == -1) {
result = -1;
break;
}
if (hmuch == 0) {
result = 0;
break;
}
buf[hmuch] = 0;
if (pager_output(buf)) {
result = 1;
break;
}
}
close(fd);
return(result);
}
|
