Function sys_ptrace

freebsd/kern/sys_process.c:461–568

#endif

int
sys_ptrace(struct thread *td, struct ptrace_args *uap)
{
	/*
	 * XXX this obfuscation is to reduce stack usage, but the register
	 * structs may be too large to put on the stack anyway.
	 */
	union {
		struct ptrace_io_desc piod;
		struct ptrace_lwpinfo pl;
		struct ptrace_vm_entry pve;
		struct dbreg dbreg;
		struct fpreg fpreg;
		struct reg reg;
		char args[sizeof(td->td_sa.args)];
		struct ptrace_sc_ret psr;
		int ptevents;
	} r;
	void *addr;
	int error = 0;

	AUDIT_ARG_PID(uap->pid);
	AUDIT_ARG_CMD(uap->req);
	AUDIT_ARG_VALUE(uap->data);
	addr = &r;
	switch (uap->req) {
	case PT_GET_EVENT_MASK:
	case PT_LWPINFO:
	case PT_GET_SC_ARGS:
	case PT_GET_SC_RET:
		break;
	case PT_GETREGS:
		bzero(&r.reg, sizeof(r.reg));
		break;
	case PT_GETFPREGS:
		bzero(&r.fpreg, sizeof(r.fpreg));
		break;
	case PT_GETDBREGS:
		bzero(&r.dbreg, sizeof(r.dbreg));
		break;
	case PT_SETREGS:
		error = copyin(uap->addr, &r.reg, sizeof(r.reg));
		break;
	case PT_SETFPREGS:
		error = copyin(uap->addr, &r.fpreg, sizeof(r.fpreg));
		break;
	case PT_SETDBREGS:
		error = copyin(uap->addr, &r.dbreg, sizeof(r.dbreg));
		break;
	case PT_SET_EVENT_MASK:
		if (uap->data != sizeof(r.ptevents))
			error = EINVAL;
		else
			error = copyin(uap->addr, &r.ptevents, uap->data);
		break;
	case PT_IO:
		error = copyin(uap->addr, &r.piod, sizeof(r.piod));
		break;