int main(int argc, char **argv) {
struct stat buf;
DIR *dir_pointer;
struct dirent *dp;
if (chdir(PLAYERS_STUFF)) {
perror(FAN_ERR_PLAY_STUFF);
exit(-1);
}
if ((dir_pointer = opendir(".")) == NULL) {
perror(FAN_ERR_PLAY_STUFF);
exit(-1);
}
for (dp = readdir(dir_pointer); dp != NULL; dp = readdir(dir_pointer)) {
if (stat(dp->d_name,&buf) == -1) {
perror(FAN_ERR_PLAY_STUFF);
exit(-1);
}
if (S_ISREG(buf.st_mode)) unlink(dp->d_name);
}
if (closedir(dir_pointer)) {
perror(FAN_ERR_PLAY_STUFF);
exit(-1);
}
if (chdir(FANTASY_ETC)) {
perror(FAN_ERR_ETC);
exit(-1);
}
if (system("tar xf initial_world.tar") == -1) {
perror(FAN_ERR_WORLD);
exit(-1);
}
if (set_current_location(PLAYERS_LOCATION,STARTING_LOCATION) == -1) {
perror(FAN_ERR_START);
exit(-1);
}
if (set_current_location(DRAGONS_LOCATION,DRAGONS_LAIR) == -1) {
perror(FAN_ERR_LAIR);
exit(-1);
}
/*commented out - to be re-introduced when Practical Sheet 9 is done*/
if (system("dragon") == -1)
perror(FAN_WARN_DRAGON);
if (system("look") == -1) {
perror(FAN_ERR_LOOK);
exit(-1);
}
exit(0);
}
void JvmtiEnvThreadState::reset_current_location(jvmtiEvent event_type, bool enabled) {
assert(event_type == JVMTI_EVENT_SINGLE_STEP || event_type == JVMTI_EVENT_BREAKPOINT,
"must be single-step or breakpoint event");
// Current location is used to detect the following:
// 1) a breakpoint event followed by single-stepping to the same bci
// 2) single-step to a bytecode that will be transformed to a fast version
// We skip to avoid posting the duplicate single-stepping event.
// If single-stepping is disabled, clear current location so that
// single-stepping to the same method and bcp at a later time will be
// detected if single-stepping is enabled at that time (see 4388912).
// If single-stepping is enabled, set the current location to the
// current method and bcp. This covers the following type of case,
// e.g., the debugger stepi command:
// - bytecode single stepped
// - SINGLE_STEP event posted and SINGLE_STEP event disabled
// - SINGLE_STEP event reenabled
// - bytecode rewritten to fast version
// If breakpoint event is disabled, clear current location only if
// single-stepping is not enabled. Otherwise, keep the thread location
// to detect any duplicate events.
if (enabled) {
// If enabling breakpoint, no need to reset.
// Can't do anything if empty stack.
if (event_type == JVMTI_EVENT_SINGLE_STEP && _thread->has_last_Java_frame()) {
jmethodID method_id;
int bci;
// The java thread stack may not be walkable for a running thread
// so get current location at safepoint.
VM_GetCurrentLocation op(_thread);
VMThread::execute(&op);
op.get_current_location(&method_id, &bci);
set_current_location(method_id, bci);
}
} else if (event_type == JVMTI_EVENT_SINGLE_STEP || !is_enabled(JVMTI_EVENT_SINGLE_STEP)) {
// If this is to disable breakpoint, also check if single-step is not enabled
clear_current_location();
}
}
// Given that a new (potential) event has come in,
// maintain the current JVMTI location on a per-thread per-env basis
// and use it to filter out duplicate events:
// - instruction rewrites
// - breakpoint followed by single step
// - single step at a breakpoint
void JvmtiEnvThreadState::compare_and_set_current_location(Method* new_method,
address new_location, jvmtiEvent event) {
int new_bci = new_location - new_method->code_base();
// The method is identified and stored as a jmethodID which is safe in this
// case because the class cannot be unloaded while a method is executing.
jmethodID new_method_id = new_method->jmethod_id();
// the last breakpoint or single step was at this same location
if (_current_bci == new_bci && _current_method_id == new_method_id) {
switch (event) {
case JVMTI_EVENT_BREAKPOINT:
// Repeat breakpoint is complicated. If we previously posted a breakpoint
// event at this location and if we also single stepped at this location
// then we skip the duplicate breakpoint.
_breakpoint_posted = _breakpoint_posted && _single_stepping_posted;
break;
case JVMTI_EVENT_SINGLE_STEP:
// Repeat single step is easy: just don't post it again.
// If step is pending for popframe then it may not be
// a repeat step. The new_bci and method_id is same as current_bci
// and current method_id after pop and step for recursive calls.
// This has been handled by clearing the location
_single_stepping_posted = true;
break;
default:
assert(false, "invalid event value passed");
break;
}
return;
}
set_current_location(new_method_id, new_bci);
_breakpoint_posted = false;
_single_stepping_posted = false;
}
