fix usertests to correctly test what happens when you call

exec() with arguments that don't fit on a single page.
This commit is contained in:
Robert Morris 2011-09-01 12:02:49 -04:00
parent 15997d5849
commit 5a23692444
4 changed files with 26 additions and 13 deletions

View file

@ -54,10 +54,10 @@ entry:
# Set up the stack pointer.
movl $(stack + STACK), %esp
# Call main(), which switches to executing at
# Jump to main(), and switch to executing at
# high addresses. The indirect call is needed because
# the assembler produces a PC-relative instruction
# for a direct call.
# for a direct jump.
mov $main, %eax
jmp *%eax

2
proc.c
View file

@ -49,7 +49,7 @@ found:
p->pid = nextpid++;
release(&ptable.lock);
// Allocate kernel stack if possible.
// Allocate kernel stack.
if((p->kstack = kalloc()) == 0){
p->state = UNUSED;
return 0;

View file

@ -1508,30 +1508,41 @@ bsstest(void)
printf(stdout, "bss test ok\n");
}
// does exec do something sensible if the arguments
// are larger than a page?
// does exec return an error if the arguments
// are larger than a page? or does it write
// below the stack and wreck the instructions/data?
void
bigargtest(void)
{
int pid, ppid;
int pid, ppid, fd;
unlink("bigarg-ok");
ppid = getpid();
pid = fork();
if(pid == 0){
char *args[32+1];
static char *args[MAXARG];
int i;
for(i = 0; i < 32; i++)
args[i] = "bigargs test: failed\n ";
args[32] = 0;
printf(stdout, "bigarg test\n");
for(i = 0; i < MAXARG-1; i++)
args[i] = "bigargs test: failed\n ";
args[MAXARG-1] = 0;
printf(stdout, "bigarg test %d\n", (MAXARG-1)*strlen(args[0]));
exec("echo", args);
printf(stdout, "bigarg test ok\n");
fd = open("bigarg-ok", O_CREATE);
close(fd);
exit();
} else if(pid < 0){
printf(stdout, "bigargtest: fork failed\n");
exit();
}
wait();
fd = open("bigarg-ok", 0);
if(fd < 0){
printf(stdout, "bigarg test failed!\n");
exit();
}
close(fd);
unlink("bigarg-ok");
}
// what happens when the file system runs out of blocks?
@ -1606,6 +1617,7 @@ main(int argc, char *argv[])
}
close(open("usertests.ran", O_CREATE));
bigargtest();
bigwrite();
bigargtest();
bsstest();

5
vm.c
View file

@ -68,7 +68,8 @@ walkpgdir(pde_t *pgdir, const void *va, char* (*alloc)(void))
// physical addresses starting at pa. va and size might not
// be page-aligned.
static int
mappages(pde_t *pgdir, void *va, uint size, uint pa, int perm, char* (*alloc)(void))
mappages(pde_t *pgdir, void *va, uint size, uint pa,
int perm, char* (*alloc)(void))
{
char *a, *last;
pte_t *pte;
@ -343,7 +344,7 @@ copyout(pde_t *pgdir, uint va, void *p, uint len)
{
char *buf, *pa0;
uint n, va0;
buf = (char*)p;
while(len > 0){
va0 = (uint)PGROUNDDOWN(va);