1.1 --- a/agent/src/os/bsd/MacosxDebuggerLocal.m Thu Feb 14 14:33:35 2013 -0500
1.2 +++ b/agent/src/os/bsd/MacosxDebuggerLocal.m Fri Feb 15 08:54:12 2013 +0100
1.3 @@ -38,6 +38,8 @@
1.4 #import <dlfcn.h>
1.5 #import <limits.h>
1.6 #import <errno.h>
1.7 +#import <sys/types.h>
1.8 +#import <sys/ptrace.h>
1.9
1.10 jboolean debug = JNI_FALSE;
1.11
1.12 @@ -430,6 +432,73 @@
1.13 return (jint) usable_tid;
1.14 }
1.15
1.16 +
1.17 +static bool ptrace_continue(pid_t pid, int signal) {
1.18 + // pass the signal to the process so we don't swallow it
1.19 + int res;
1.20 + if ((res = ptrace(PT_CONTINUE, pid, (caddr_t)1, signal)) < 0) {
1.21 + fprintf(stderr, "attach: ptrace(PT_CONTINUE, %d) failed with %d\n", pid, res);
1.22 + return false;
1.23 + }
1.24 + return true;
1.25 +}
1.26 +
1.27 +// waits until the ATTACH has stopped the process
1.28 +// by signal SIGSTOP
1.29 +static bool ptrace_waitpid(pid_t pid) {
1.30 + int ret;
1.31 + int status;
1.32 + while (true) {
1.33 + // Wait for debuggee to stop.
1.34 + ret = waitpid(pid, &status, 0);
1.35 + if (ret >= 0) {
1.36 + if (WIFSTOPPED(status)) {
1.37 + // Any signal will stop the thread, make sure it is SIGSTOP. Otherwise SIGSTOP
1.38 + // will still be pending and delivered when the process is DETACHED and the process
1.39 + // will go to sleep.
1.40 + if (WSTOPSIG(status) == SIGSTOP) {
1.41 + // Debuggee stopped by SIGSTOP.
1.42 + return true;
1.43 + }
1.44 + if (!ptrace_continue(pid, WSTOPSIG(status))) {
1.45 + fprintf(stderr, "attach: Failed to correctly attach to VM. VM might HANG! [PTRACE_CONT failed, stopped by %d]\n", WSTOPSIG(status));
1.46 + return false;
1.47 + }
1.48 + } else {
1.49 + fprintf(stderr, "attach: waitpid(): Child process exited/terminated (status = 0x%x)\n", status);
1.50 + return false;
1.51 + }
1.52 + } else {
1.53 + switch (errno) {
1.54 + case EINTR:
1.55 + continue;
1.56 + break;
1.57 + case ECHILD:
1.58 + fprintf(stderr, "attach: waitpid() failed. Child process pid (%d) does not exist \n", pid);
1.59 + break;
1.60 + case EINVAL:
1.61 + fprintf(stderr, "attach: waitpid() failed. Invalid options argument.\n");
1.62 + break;
1.63 + default:
1.64 + fprintf(stderr, "attach: waitpid() failed. Unexpected error %d\n",errno);
1.65 + break;
1.66 + }
1.67 + return false;
1.68 + }
1.69 + }
1.70 +}
1.71 +
1.72 +// attach to a process/thread specified by "pid"
1.73 +static bool ptrace_attach(pid_t pid) {
1.74 + int res;
1.75 + if ((res = ptrace(PT_ATTACH, pid, 0, 0)) < 0) {
1.76 + fprintf(stderr, "ptrace(PT_ATTACH, %d) failed with %d\n", pid, res);
1.77 + return false;
1.78 + } else {
1.79 + return ptrace_waitpid(pid);
1.80 + }
1.81 +}
1.82 +
1.83 /*
1.84 * Class: sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal
1.85 * Method: attach0
1.86 @@ -445,7 +514,8 @@
1.87 else
1.88 debug = JNI_FALSE;
1.89 if (debug) printf("attach0 called for jpid=%d\n", (int)jpid);
1.90 -
1.91 +
1.92 + // get the task from the pid
1.93 kern_return_t result;
1.94 task_t gTask = 0;
1.95 result = task_for_pid(mach_task_self(), jpid, &gTask);
1.96 @@ -455,6 +525,13 @@
1.97 }
1.98 putTask(env, this_obj, gTask);
1.99
1.100 + // use ptrace to stop the process
1.101 + // on os x, ptrace only needs to be called on the process, not the individual threads
1.102 + if (ptrace_attach(jpid) != true) {
1.103 + mach_port_deallocate(mach_task_self(), gTask);
1.104 + THROW_NEW_DEBUGGER_EXCEPTION("Can't attach to the process");
1.105 + }
1.106 +
1.107 id symbolicator = nil;
1.108 id jrsSymbolicator = objc_lookUpClass("JRSSymbolicator");
1.109 if (jrsSymbolicator != nil) {
1.110 @@ -486,6 +563,21 @@
1.111 if (debug) printf("detach0 called\n");
1.112
1.113 task_t gTask = getTask(env, this_obj);
1.114 +
1.115 + // detach from the ptraced process causing it to resume execution
1.116 + int pid;
1.117 + kern_return_t k_res;
1.118 + k_res = pid_for_task(gTask, &pid);
1.119 + if (k_res != KERN_SUCCESS) {
1.120 + fprintf(stderr, "detach: pid_for_task(%d) failed (%d)\n", pid, k_res);
1.121 + }
1.122 + else {
1.123 + int res = ptrace(PT_DETACH, pid, 0, 0);
1.124 + if (res < 0) {
1.125 + fprintf(stderr, "detach: ptrace(PT_DETACH, %d) failed (%d)\n", pid, res);
1.126 + }
1.127 + }
1.128 +
1.129 mach_port_deallocate(mach_task_self(), gTask);
1.130 id symbolicator = getSymbolicator(env, this_obj);
1.131 if (symbolicator != nil) {
