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#include "user.h"
#include "fcntl.h"
char buf[2048];
// simple fork and pipe read/write
void
pipe1(void)
{
int fds[2], pid;
int seq = 0, i, n, cc, total;
pipe(fds);
pid = fork();
if(pid == 0){
close(fds[0]);
for(n = 0; n < 5; n++){
for(i = 0; i < 1033; i++)
buf[i] = seq++;
if(write(fds[1], buf, 1033) != 1033){
printf(1, "pipe1 oops 1\n");
exit();
}
}
exit();
} else {
close(fds[1]);
total = 0;
cc = 1;
while((n = read(fds[0], buf, cc)) > 0){
for(i = 0; i < n; i++){
if((buf[i] & 0xff) != (seq++ & 0xff)){
printf(1, "pipe1 oops 2\n");
return;
}
}
total += n;
cc = cc * 2;
if(cc > sizeof(buf))
cc = sizeof(buf);
}
if(total != 5 * 1033)
printf(1, "pipe1 oops 3\n");
close(fds[0]);
wait();
}
puts("pipe1 ok\n");
}
// meant to be run w/ at most two CPUs
void
preempt(void)
{
int pid1, pid2, pid3;
int pfds[2];
pid1 = fork();
if(pid1 == 0)
for(;;)
;
pid2 = fork();
if(pid2 == 0)
for(;;)
;
pipe(pfds);
pid3 = fork();
if(pid3 == 0){
close(pfds[0]);
if(write(pfds[1], "x", 1) != 1)
printf(1, "preempt write error");
close(pfds[1]);
for(;;)
;
}
close(pfds[1]);
if(read(pfds[0], buf, sizeof(buf)) != 1){
printf(1, "preempt read error");
return;
}
close(pfds[0]);
kill(pid1);
kill(pid2);
kill(pid3);
wait();
wait();
wait();
puts("preempt ok\n");
}
// try to find any races between exit and wait
void
exitwait(void)
{
int i, pid;
for(i = 0; i < 100; i++){
pid = fork();
if(pid < 0){
printf(1, "fork failed\n");
return;
}
if(pid){
if(wait() != pid){
printf(1, "wait wrong pid\n");
return;
}
} else {
exit();
}
}
puts("exitwait ok\n");
}
// two processes write to the same file descriptor
// is the offset shared? does inode locking work?
void
sharedfd()
{
int fd, pid, i, n, nc, np;
char buf[10];
unlink("sharedfd");
fd = open("sharedfd", O_CREATE|O_RDWR);
if(fd < 0){
printf(1, "usertests: cannot open sharedfd for writing");
return;
}
pid = fork();
memset(buf, pid==0?'c':'p', sizeof(buf));
for(i = 0; i < 100; i++){
if(write(fd, buf, sizeof(buf)) != sizeof(buf)){
printf(1, "usertests: write sharedfd failed\n");
break;
}
}
if(pid == 0)
exit();
else
wait();
close(fd);
fd = open("sharedfd", 0);
if(fd < 0){
printf(1, "usertests: cannot open sharedfd for reading\n");
return;
}
nc = np = 0;
while((n = read(fd, buf, sizeof(buf))) > 0){
for(i = 0; i < sizeof(buf); i++){
if(buf[i] == 'c')
nc++;
if(buf[i] == 'p')
np++;
}
}
close(fd);
if(nc == 1000 && np == 1000)
printf(1, "sharedfd ok\n");
else
printf(1, "sharedfd oops %d %d\n", nc, np);
}
// two processes write two different files at the same
// time, to test block allocation.
void
twofiles()
{
int fd, pid, i, j, n, total;
char *fname;
unlink("f1");
unlink("f2");
pid = fork();
if(pid < 0){
puts("fork failed\n");
return;
}
fname = pid ? "f1" : "f2";
fd = open(fname, O_CREATE | O_RDWR);
if(fd < 0){
puts("create failed\n");
exit();
}
memset(buf, pid?'p':'c', 512);
for(i = 0; i < 12; i++){
if((n = write(fd, buf, 500)) != 500){
printf(1, "write failed %d\n", n);
exit();
}
}
close(fd);
if(pid)
wait();
else
exit();
for(i = 0; i < 2; i++){
fd = open(i?"f1":"f2", 0);
total = 0;
while((n = read(fd, buf, sizeof(buf))) > 0){
for(j = 0; j < n; j++){
if(buf[j] != (i?'p':'c')){
puts("wrong char\n");
exit();
}
}
total += n;
}
close(fd);
if(total != 12*500){
printf(1, "wrong length %d\n", total);
exit();
}
}
puts("twofiles ok\n");
}
int
main(int argc, char *argv[])
{
puts("usertests starting\n");
twofiles();
sharedfd();
pipe1();
preempt();
exitwait();
puts("usertests finished\n");
exit();
}
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