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#include <stdio.h>
#include <comedilib.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <getopt.h>
#include <ctype.h>
#include <math.h>
#include <sys/time.h>
#include <string.h>
#include <sys/mman.h>
#include <signal.h>
#include <setjmp.h>
#include <stdlib.h>
#include "comedi_test.h"
/* XXX this should come from elsewhere */
#define PAGE_SIZE 4096
#define N_SAMPLES 10000
sigjmp_buf jump_env;
void segv_handler(int num)
{
siglongjmp(jump_env,1);
}
int test_segfault(void *memptr)
{
int ret;
struct sigaction act;
struct sigaction oldact;
memset(&act,0,sizeof(act));
act.sa_handler=&segv_handler;
ret = sigaction(SIGSEGV,&act,&oldact);
if(ret)
{
fprintf(stderr, "sigaction failed\n");
return 0;
}
ret=sigsetjmp(jump_env, 1);
if(!ret) *((volatile char *)(memptr));
sigaction(SIGSEGV,&oldact,NULL);
return ret;
}
int test_mmap(void)
{
comedi_cmd cmd;
unsigned char *buf;
unsigned int chanlist[1];
int go;
int fails;
int total=0;
int ret;
void *b;
unsigned char *adr;
unsigned char *map;
unsigned int flags;
int i;
unsigned sample_size;
unsigned map_len;
flags = comedi_get_subdevice_flags(device,subdevice);
/* attempt to make subdevice the current 'read' subdevice */
if(flags&SDF_CMD_READ) comedi_set_read_subdevice(device,subdevice);
if(!(flags&SDF_CMD) || (comedi_get_read_subdevice(device)!=subdevice)){
printf("not applicable\n");
return 0;
}
if(flags & SDF_LSAMPL) sample_size = sizeof(lsampl_t);
else sample_size = sizeof(sampl_t);
map_len = sample_size * N_SAMPLES;
if(comedi_get_cmd_generic_timed(device, subdevice, &cmd, 1, 1)<0){
printf("E: comedi_get_cmd_generic_timed failed\n");
return 0;
}
buf=malloc(sample_size * N_SAMPLES);
map = mmap(NULL, map_len,PROT_READ, MAP_SHARED, comedi_fileno(device),0);
if(!map){
printf("E: mmap() failed\n");
return 0;
}
/* test readability */
for(adr = map; adr < map + map_len; adr += PAGE_SIZE){
ret=test_segfault(adr);
if(ret){
printf("E: %p failed\n",adr);
}else{
printf("%p ok\n",adr);
}
}
if(realtime)cmd.flags |= TRIG_RT;
cmd.chanlist = chanlist;
cmd.scan_end_arg = 1;
cmd.stop_arg = N_SAMPLES;
cmd.chanlist_len = 1;
chanlist[0] = CR_PACK(0,0,0);
comedi_command(device,&cmd);
go=1;
b=buf;
while(go){
ret = read(comedi_fileno(device), b,
(N_SAMPLES * sample_size) - total);
if(ret<0){
if(errno==EAGAIN){
usleep(10000);
}else{
go = 0;
perror("read");
}
}else if(ret==0){
go = 0;
}else{
total += ret;
b += ret;
if(verbose) printf("read %d %d\n",ret,total);
if(total >= (N_SAMPLES * sample_size)){
go = 0;
}
}
}
fails = 0;
for(i=0;i<total;i++){
if(buf[i]!=map[i]){
if(fails==0)printf("E: mmap compare failed\n");
printf("offset %d (read=%02x mmap=%02x)\n",i,
buf[i], map[i]);
fails++;
if(fails>10)break;
}
}
if(fails==0) printf("compare ok\n");
munmap(map, map_len);
/* test if area is really unmapped */
for(adr = map; adr < map + map_len; adr += PAGE_SIZE){
ret=test_segfault(adr);
if(ret){
printf("%p segfaulted (ok)\n",adr);
}else{
printf("E: %p still mapped\n",adr);
}
}
free(buf);
return 0;
}
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