/**
* Carry out the syscall specified in the stub stack.
* @param proc the PCB of the process to execute the stub call
* @return the return value of the call
*/
static int
host_syscall_in_child (struct proc_struct *proc)
{
struct user_regs_struct regs;
int err, pid = proc->arch.host->host_pid;
err = syscall4 (__NR_ptrace, PTRACE_GETREGS, pid, 0, (long)®s);
if (err < 0) {
kprintf ("host_syscall_in_child: cannot get regs\n");
return -1;
}
/* 'stub_exec_syscall' is the entry of all stub calls. */
regs.eip = STUB_CODE + (unsigned long)stub_exec_syscall - (unsigned long) &__syscall_stub_start;
err = syscall4 (__NR_ptrace, PTRACE_SETREGS, pid, 0, (long)®s);
if (err < 0) {
kprintf ("host_syscall_in_child: cannot set regs\n");
return -1;
}
err = syscall4 (__NR_ptrace, PTRACE_CONT, pid, 0, 0);
if (err < 0) {
kprintf ("host_syscall_in_child: cannot continue the child\n");
return -1;
}
err = wait_stub_done (pid);
if (err < 0) {
kprintf ("host_syscall_in_child: wait stub done failed with err = %d\n", err);
return -1;
}
err = current_stub_frame(proc->arch.host->stub_stack)->eax;
return err;
}
int peek_ipc_message( ipc_port_id port_id, uint32_t* code, size_t* size, uint64_t timeout ) {
return syscall4(
SYS_peek_ipc_message,
port_id,
( int )code,
( int )size,
( int )&timeout
);
}
int send_ipc_message( ipc_port_id port_id, uint32_t code, const void* data, size_t size ) {
return syscall4(
SYS_send_ipc_message,
port_id,
code,
( int )data,
size
);
}
ssize_t pread( int fd, void* buf, size_t count, off_t offset ) {
int error;
error = syscall4( SYS_pread, fd, ( int )buf, count, ( int )&offset );
if ( error < 0 ) {
errno = -error;
return -1;
}
return error;
}
off_t lseek( int fd, off_t offset, int whence ) {
int error;
off_t result;
error = syscall4( SYS_lseek, fd, ( int )&offset, whence, ( int )&result );
if ( error < 0 ) {
errno = -error;
return ( off_t )-1;
}
return result;
}
pid_t wait4( pid_t pid, int* status, int options, struct rusage* rusage ) {
int error;
error = syscall4(
SYS_wait4,
pid,
( int )status,
options,
( int )rusage
);
if ( error < 0 ) {
errno = -error;
return -1;
}
return error;
}
int createdev(const char *path,mode_t mode,uint type,uint ops) {
char apath[MAX_PATH_LEN];
return syscall4(SYSCALL_CRTDEV,(ulong)abspath(apath,sizeof(apath),path),mode,type,ops);
}
