8351491: Add info from release file to hserr file

Reviewed-by: dholmes, lucy

src/hotspot/share/runtime/os.cpp

@@ -1534,6 +1534,56 @@ bool os::set_boot_path(char fileSep, char pathSep) {
   return false;
 }
 
+static char* _image_release_file_content = nullptr;
+
+void os::read_image_release_file() {
+  assert(_image_release_file_content == nullptr, "release file content must not be already set");
+  const char* home = Arguments::get_java_home();
+  stringStream ss;
+  ss.print("%s/release", home);
+
+  FILE* file = fopen(ss.base(), "rb");
+  if (file == nullptr) {
+    return;
+  }
+  fseek(file, 0, SEEK_END);
+  long sz = ftell(file);
+  if (sz == -1) {
+    return;
+  }
+  fseek(file, 0, SEEK_SET);
+
+  char* tmp = (char*) os::malloc(sz + 1, mtInternal);
+  if (tmp == nullptr) {
+    fclose(file);
+    return;
+  }
+
+  size_t elements_read = fread(tmp, 1, sz, file);
+  if (elements_read < (size_t)sz) {
+    tmp[elements_read] = '\0';
+  } else {
+    tmp[sz] = '\0';
+  }
+  // issues with \r in line endings on Windows, so better replace those
+  for (size_t i = 0; i < elements_read; i++) {
+    if (tmp[i] == '\r') {
+      tmp[i] = ' ';
+    }
+  }
+  Atomic::release_store(&_image_release_file_content, tmp);
+  fclose(file);
+}
+
+void os::print_image_release_file(outputStream* st) {
+  char* ifrc = Atomic::load_acquire(&_image_release_file_content);
+  if (ifrc != nullptr) {
+    st->print_cr("%s", ifrc);
+  } else {
+    st->print_cr("<release file has not been read>");
+  }
+}
+
 bool os::file_exists(const char* filename) {
   struct stat statbuf;
   if (filename == nullptr || strlen(filename) == 0) {

src/hotspot/share/runtime/os.hpp

@@ -670,6 +670,11 @@ class os: AllStatic {
   static FILE* fopen(const char* path, const char* mode);
   static jlong lseek(int fd, jlong offset, int whence);
   static bool file_exists(const char* file);
+
+  // read/store and print the release file of the image
+  static void read_image_release_file();
+  static void print_image_release_file(outputStream* st);
+
   // This function, on Windows, canonicalizes a given path (see os_windows.cpp for details).
   // On Posix, this function is a noop: it does not change anything and just returns
   // the input pointer.

src/hotspot/share/runtime/threads.cpp

@@ -425,6 +425,19 @@ void Threads::initialize_jsr292_core_classes(TRAPS) {
   }
 }
 
+// One-shot PeriodicTask subclass for reading the release file
+class ReadReleaseFileTask : public PeriodicTask {
+ public:
+  ReadReleaseFileTask() : PeriodicTask(100) {}
+
+  virtual void task() {
+    os::read_image_release_file();
+
+    // Reclaim our storage and disenroll ourself.
+    delete this;
+  }
+};
+
 jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) {
   extern void JDK_Version_init();
 
@@ -580,6 +593,10 @@ jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) {
     return status;
   }
 
+  // Have the WatcherThread read the release file in the background.
+  ReadReleaseFileTask* read_task = new ReadReleaseFileTask();
+  read_task->enroll();
+
   // Create WatcherThread as soon as we can since we need it in case
   // of hangs during error reporting.
   WatcherThread::start();

src/hotspot/share/utilities/vmError.cpp

@@ -1259,6 +1259,10 @@ void VMError::report(outputStream* st, bool _verbose) {
     LogConfiguration::describe_current_configuration(st);
     st->cr();
 
+  STEP_IF("printing release file content", _verbose)
+    st->print_cr("Release file:");
+    os::print_image_release_file(st);
+
   STEP_IF("printing all environment variables", _verbose)
     os::print_environment_variables(st, env_list);
     st->cr();
@@ -1439,6 +1443,10 @@ void VMError::print_vm_info(outputStream* st) {
   LogConfiguration::describe(st);
   st->cr();
 
+  // STEP("printing release file content")
+  st->print_cr("Release file:");
+  os::print_image_release_file(st);
+
   // STEP("printing all environment variables")
 
   os::print_environment_variables(st, env_list);