comedilib/testing/mmap.c
2002-03-18 21:48:14 +00:00

158 lines
2.6 KiB
C

#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
#define BUFSZ N_SAMPLES*sizeof(sampl_t)
#define MAPLEN 20480
jmp_buf jump_env;
void segv_handler(int num)
{
longjmp(jump_env,1);
}
int test_segfault(void *memptr)
{
volatile char tmp;
int ret;
ret=setjmp(jump_env);
if(!ret) tmp = *((char *)(memptr));
return ret;
}
void setup_segfaulter(void)
{
struct sigaction act;
memset(&act,0,sizeof(act));
act.sa_handler=&segv_handler;
sigaction(SIGSEGV,&act,NULL);
}
int test_mmap(void)
{
comedi_cmd cmd;
char *buf;
unsigned int chanlist[1];
int go;
int total=0;
int ret;
void *b, *adr;
sampl_t *map;
unsigned int flags;
int i;
flags = comedi_get_subdevice_flags(device,subdevice);
if(!(flags&SDF_CMD) || flags&SDF_WRITEABLE){
printf("not applicable\n");
return 0;
}
if(comedi_get_cmd_generic_timed(device,subdevice,&cmd,1)<0){
printf("E: comedi_get_cmd_generic_timed failed\n");
return 0;
}
setup_segfaulter();
buf=malloc(BUFSZ);
map=mmap(NULL,MAPLEN,PROT_READ,MAP_SHARED,comedi_fileno(device),0);
if(!map){
printf("E: mmap() failed\n");
return 0;
}
/* test readability */
for(adr=map;adr<(void *)map+MAPLEN;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,BUFSZ);
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);
}
}
go = 1;
for(i=0;i<total;i++){
if(buf[i]!=((char *)map)[i]){
printf("E: mmap compare failed\n");
printf("offset %d (read=%02x mmap=%02x)\n",i,
buf[i], ((char *)map)[i]);
go = 0;
break;
}
}
if(go) printf("compare ok\n");
munmap(map,MAPLEN);
/* test if area is really unmapped */
for(adr=map;adr<(void *)map+MAPLEN;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;
}