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#include <stdio.h>
#include <stdlib.h>
#include <ucontext.h>
#include "tests/sys_mman.h"
#include "valgrind.h"
#define STACK_SIZE (10 * 4096)
// This test is checking the libc context calls (setcontext, etc.) and
// checks that Valgrind notices their stack changes properly.
typedef struct ucontext mycontext;
mycontext ctx1, ctx2, oldc;
int count;
void hello(mycontext *newc)
{
printf("hello, world: %d\n", count);
if (count++ == 2)
newc = &oldc;
setcontext(newc);
}
int init_context(mycontext *uc)
{
void *stack;
int ret;
if (getcontext(uc) == -1) {
//perror("getcontext");
printf("getcontext() doesn't seem to work\n");
exit(1);
}
stack = (void *)mmap(0, STACK_SIZE, PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
if (stack == (void*)-1) {
perror("mmap");
exit(1);
}
ret = VALGRIND_STACK_REGISTER(stack, stack + STACK_SIZE);
uc->uc_link = NULL;
uc->uc_stack.ss_sp = stack;
uc->uc_stack.ss_size = STACK_SIZE;
uc->uc_stack.ss_flags = 0;
return ret;
}
int main(int argc, char **argv)
{
int c1 = init_context(&ctx1);
int c2 = init_context(&ctx2);
makecontext(&ctx1, (void (*)()) hello, 1, &ctx2);
makecontext(&ctx2, (void (*)()) hello, 1, &ctx1);
swapcontext(&oldc, &ctx1);
VALGRIND_STACK_DEREGISTER(c1);
//free(ctx1.uc_stack.ss_sp);
VALGRIND_STACK_DEREGISTER(c2);
//free(ctx2.uc_stack.ss_sp);
return 0;
}
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