agent/src/os/bsd/MacosxDebuggerLocal.m

rev 4134 : 8008102: SA on OS X does not stop the attached process
Reviewed-by:

*** 36,45 ****
--- 36,47 ----
  #import <stdlib.h>
  #import <strings.h>
  #import <dlfcn.h>
  #import <limits.h>
  #import <errno.h>
+ #import <sys/types.h>
+ #import <sys/ptrace.h>
  
  jboolean debug = JNI_FALSE;
  
  static jfieldID symbolicatorID = 0; // set in _init0
  static jfieldID taskID = 0; // set in _init0
*** 444,462 ****
--- 446,485 ----
      debug = JNI_TRUE;
    else
      debug = JNI_FALSE;
    if (debug) printf("attach0 called for jpid=%d\n", (int)jpid);
    
+   // get the task from the pid
    kern_return_t result;
    task_t gTask = 0;
    result = task_for_pid(mach_task_self(), jpid, &gTask);
    if (result != KERN_SUCCESS) {
      fprintf(stderr, "attach: task_for_pid(%d) failed (%d)\n", (int)jpid, result);
      THROW_NEW_DEBUGGER_EXCEPTION("Can't attach to the process");
    }
    putTask(env, this_obj, gTask);
  
+   // use ptrace to stop the process
+   // on os x, ptrace only needs to be called on the process, not the individual threads
+   int res, status;  
+   res = ptrace(PT_ATTACH, jpid, 0, 0);
+   if (res < 0) {
+     fprintf(stderr, "attach: ptrace(PT_ATTACH, %d) failed (%d)\n", (int)jpid, res);
+     THROW_NEW_DEBUGGER_EXCEPTION("Can't attach to the process");
+   }
+   
+   res = waitpid(jpid, &status, 0);
+   if (res < 0) {
+     fprintf(stderr, "attach: waitpid(%d) failed (%d, %d)\n", (int)jpid, res, errno);
+     THROW_NEW_DEBUGGER_EXCEPTION("Can't attach to the process");
+   }
+   
+   if (! WIFSTOPPED(status)) {
+     fprintf(stderr, "attach: stopping the process failed %d\n", status);
+     THROW_NEW_DEBUGGER_EXCEPTION("Can't attach to the process");
+   }  
+ 
    id symbolicator = nil;
    id jrsSymbolicator = objc_lookUpClass("JRSSymbolicator");
    if (jrsSymbolicator != nil) {
      id (*dynamicCall)(id, SEL, pid_t) = (id (*)(id, SEL, pid_t))&objc_msgSend;
      symbolicator = dynamicCall(jrsSymbolicator, @selector(symbolicatorForPid:), (pid_t)jpid);
*** 484,493 ****
--- 507,531 ----
  {
  JNF_COCOA_ENTER(env);
    if (debug) printf("detach0 called\n");
  
    task_t gTask = getTask(env, this_obj);
+ 
+   // detach from the ptraced process causing it to resume execution
+   int pid;
+   kern_return_t k_res;
+   k_res = pid_for_task(gTask, &pid);
+   if (k_res != KERN_SUCCESS) {
+     fprintf(stderr, "detach: pid_for_task(%d) failed (%d)\n", pid, k_res);
+   }
+   else {
+     int res = ptrace(PT_DETACH, pid, 0, 0);
+     if (res < 0) {
+       fprintf(stderr, "detach: ptrace(PT_DETACH, %d) failed (%d)\n", pid, res);
+     }
+   }
+   
    mach_port_deallocate(mach_task_self(), gTask);
    id symbolicator = getSymbolicator(env, this_obj);
    if (symbolicator != nil) {
      CFRelease(symbolicator);
    }