90 
  91   // Prints a one-line description of a combination of sigaction.sa_flags.
  92   static void print_sa_flags(outputStream* st, int flags);
  93 
  94   static address ucontext_get_pc(const ucontext_t* ctx);
  95   // Set PC into context. Needed for continuation after signal.
  96   static void ucontext_set_pc(ucontext_t* ctx, address pc);
  97 
  98   // Helper function; describes pthread attributes as short string. String is written
  99   // to buf with len buflen; buf is returned.
 100   static char* describe_pthread_attr(char* buf, size_t buflen, const pthread_attr_t* attr);
 101 
 102   // A safe implementation of realpath which will not cause a buffer overflow if the resolved path
 103   //   is longer than PATH_MAX.
 104   // On success, returns 'outbuf', which now contains the path.
 105   // On error, it will return NULL and set errno. The content of 'outbuf' is undefined.
 106   // On truncation error ('outbuf' too small), it will return NULL and set errno to ENAMETOOLONG.
 107   static char* realpath(const char* filename, char* outbuf, size_t outbuflen);
 108 };
 109 





 110 /*
 111  * Crash protection for the watcher thread. Wrap the callback
 112  * with a sigsetjmp and in case of a SIGSEGV/SIGBUS we siglongjmp
 113  * back.
 114  * To be able to use this - don't take locks, don't rely on destructors,
 115  * don't make OS library calls, don't allocate memory, don't print,
 116  * don't call code that could leave the heap / memory in an inconsistent state,
 117  * or anything else where we are not in control if we suddenly jump out.
 118  */
 119 class WatcherThreadCrashProtection : public StackObj {
 120 public:
 121   WatcherThreadCrashProtection();
 122   bool call(os::CrashProtectionCallback& cb);
 123 
 124   static void check_crash_protection(int signal, Thread* thread);
 125 private:
 126   void restore();
 127   sigjmp_buf _jmpbuf;
 128 };
 129 

  90 
  91   // Prints a one-line description of a combination of sigaction.sa_flags.
  92   static void print_sa_flags(outputStream* st, int flags);
  93 
  94   static address ucontext_get_pc(const ucontext_t* ctx);
  95   // Set PC into context. Needed for continuation after signal.
  96   static void ucontext_set_pc(ucontext_t* ctx, address pc);
  97 
  98   // Helper function; describes pthread attributes as short string. String is written
  99   // to buf with len buflen; buf is returned.
 100   static char* describe_pthread_attr(char* buf, size_t buflen, const pthread_attr_t* attr);
 101 
 102   // A safe implementation of realpath which will not cause a buffer overflow if the resolved path
 103   //   is longer than PATH_MAX.
 104   // On success, returns 'outbuf', which now contains the path.
 105   // On error, it will return NULL and set errno. The content of 'outbuf' is undefined.
 106   // On truncation error ('outbuf' too small), it will return NULL and set errno to ENAMETOOLONG.
 107   static char* realpath(const char* filename, char* outbuf, size_t outbuflen);
 108 };
 109 
 110 // On POSIX platforms the signal handler is global so we just do the write.
 111 static void write_memory_serialize_page_with_handler(JavaThread* thread) {
 112   write_memory_serialize_page(thread);
 113 }
 114 
 115 /*
 116  * Crash protection for the watcher thread. Wrap the callback
 117  * with a sigsetjmp and in case of a SIGSEGV/SIGBUS we siglongjmp
 118  * back.
 119  * To be able to use this - don't take locks, don't rely on destructors,
 120  * don't make OS library calls, don't allocate memory, don't print,
 121  * don't call code that could leave the heap / memory in an inconsistent state,
 122  * or anything else where we are not in control if we suddenly jump out.
 123  */
 124 class WatcherThreadCrashProtection : public StackObj {
 125 public:
 126   WatcherThreadCrashProtection();
 127   bool call(os::CrashProtectionCallback& cb);
 128 
 129   static void check_crash_protection(int signal, Thread* thread);
 130 private:
 131   void restore();
 132   sigjmp_buf _jmpbuf;
 133 };
 134