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
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
|
/********************************************************************
* Description: sampler_usr.c
* User space part of "sampler", a HAL component that
* can be used to sample data from HAL pins and write
* it to a file at a specific realtime sample rate.
*
* Author: John Kasunich <jmkasunich at sourceforge dot net>
* License: GPL Version 2
*
* Copyright (c) 2006 All rights reserved.
*
********************************************************************/
/** This file, 'sampler_usr.c', is the user part of a HAL component
that allows values to be sampled from HAL pins at a uniform
realtime sample rate, and writes them to a stdout (from which
they can be redirected to a file). When the realtime module
is loaded, it creates a stream in shared memory and begins capturing
samples to the stream. Then, the user space program 'hal_sampler'
is invoked to read from the stream and print to stdout.
Invoking:
halsampler [-c chan_num] [-n num_samples] [-t]
'chan_num', if present, specifies the sampler channel to use.
The default is channel zero.
'num_samples', if present, specifies the number of samples
to be printed, after which the program will exit. If omitted
it will print continuously until killed.
'-t' tells sampler to print the sample number at the start
of each line.
*/
/** This program is free software; you can redistribute it and/or
modify it under the terms of version 2 of the GNU General
Public License as published by the Free Software Foundation.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
THE AUTHORS OF THIS LIBRARY ACCEPT ABSOLUTELY NO LIABILITY FOR
ANY HARM OR LOSS RESULTING FROM ITS USE. IT IS _EXTREMELY_ UNWISE
TO RELY ON SOFTWARE ALONE FOR SAFETY. Any machinery capable of
harming persons must have provisions for completely removing power
from all motors, etc, before persons enter any danger area. All
machinery must be designed to comply with local and national safety
codes, and the authors of this software can not, and do not, take
any responsibility for such compliance.
This code was written as part of the EMC HAL project. For more
information, go to www.linuxcnc.org.
*/
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "rtapi.h" /* RTAPI realtime OS API */
#include "hal.h" /* HAL public API decls */
#include "streamer.h"
/***********************************************************************
* LOCAL FUNCTION DECLARATIONS *
************************************************************************/
/***********************************************************************
* GLOBAL VARIABLES *
************************************************************************/
int comp_id = -1; /* -1 means hal_init() not called yet */
int shmem_id = -1;
int exitval = 1; /* program return code - 1 means error */
int ignore_sig = 0; /* used to flag critical regions */
char comp_name[HAL_NAME_LEN+1]; /* name for this instance of sampler */
/***********************************************************************
* MAIN PROGRAM *
************************************************************************/
/* signal handler */
static sig_atomic_t stop;
static void quit(int sig)
{
if ( ignore_sig ) {
return;
}
stop = 1;
}
#define BUF_SIZE 4000
int main(int argc, char **argv)
{
int n, channel, tag;
long int samples;
unsigned this_sample, last_sample=0;
char *cp, *cp2;
hal_stream_t stream;
/* set return code to "fail", clear it later if all goes well */
exitval = 1;
channel = 0;
tag = 0;
samples = -1; /* -1 means run forever */
/* FIXME - if I wasn't so lazy I'd learn how to use getopt() here */
for ( n = 1 ; n < argc ; n++ ) {
cp = argv[n];
if ( *cp != '-' ) {
break;
}
switch ( *(++cp) ) {
case 'c':
if (( *(++cp) == '\0' ) && ( ++n < argc )) {
cp = argv[n];
}
channel = strtol(cp, &cp2, 10);
if (( *cp2 ) || ( channel < 0 ) || ( channel >= MAX_SAMPLERS )) {
fprintf(stderr,"ERROR: invalid channel number '%s'\n", cp );
exit(1);
}
break;
case 'n':
if (( *(++cp) == '\0' ) && ( ++n < argc )) {
cp = argv[n];
}
samples = strtol(cp, &cp2, 10);
if (( *cp2 ) || ( samples < 0 )) {
fprintf(stderr, "ERROR: invalid sample count '%s'\n", cp );
exit(1);
}
break;
case 't':
tag = 1;
break;
default:
fprintf(stderr,"ERROR: unknown option '%s'\n", cp );
exit(1);
break;
}
}
if(n < argc) {
int fd;
if(argc > n+1) {
fprintf(stderr, "ERROR: At most one filename may be specified\n");
exit(1);
}
// make stdout be the named file
fd = open(argv[n], O_WRONLY | O_CREAT | O_TRUNC, 0666);
close(1);
dup2(fd, 1);
}
/* register signal handlers - if the process is killed
we need to call hal_exit() to free the shared memory */
signal(SIGINT, quit);
signal(SIGTERM, quit);
signal(SIGPIPE, quit);
/* connect to HAL */
/* create a unique module name, to allow for multiple samplers */
snprintf(comp_name, sizeof(comp_name), "halsampler%d", getpid());
/* connect to the HAL */
ignore_sig = 1;
comp_id = hal_init(comp_name);
ignore_sig = 0;
/* check result */
if (comp_id < 0) {
fprintf(stderr, "ERROR: hal_init() failed: %d\n", comp_id );
goto out;
}
hal_ready(comp_id);
int res = hal_stream_attach(&stream, comp_id, SAMPLER_SHMEM_KEY+channel, 0);
if (res < 0) {
errno = -res;
perror("hal_stream_attach");
goto out;
}
int num_pins = hal_stream_element_count(&stream);
while ( samples != 0 ) {
union hal_stream_data buf[num_pins];
hal_stream_wait_readable(&stream, &stop);
if(stop) break;
int res = hal_stream_read(&stream, buf, &this_sample);
if (res < 0) {
errno = -res;
perror("hal_stream_read");
goto out;
}
++last_sample;
if ( this_sample != last_sample ) {
printf ( "overrun\n");
last_sample = this_sample;
}
if ( tag ) {
printf ( "%d ", this_sample-1 );
}
for ( n = 0 ; n < num_pins; n++ ) {
switch ( hal_stream_element_type(&stream, n) ) {
case HAL_FLOAT:
printf ( "%f ", buf[n].f);
break;
case HAL_BIT:
if ( buf[n].b ) {
printf ( "1 " );
} else {
printf ( "0 " );
}
break;
case HAL_U32:
printf ( "%lu ", (unsigned long)buf[n].u);
break;
case HAL_S32:
printf ( "%ld ", (long)buf[n].s);
break;
default:
/* better not happen */
goto out;
}
}
printf ( "\n" );
if ( samples > 0 ) {
samples--;
}
}
/* run was successful */
exitval = 0;
out:
ignore_sig = 1;
hal_stream_detach(&stream);
if ( comp_id >= 0 ) {
hal_exit(comp_id);
}
return exitval;
}
|
