iklam@7089: /*
ccheung@8184:  * Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved.
iklam@7089:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
iklam@7089:  *
iklam@7089:  * This code is free software; you can redistribute it and/or modify it
iklam@7089:  * under the terms of the GNU General Public License version 2 only, as
iklam@7089:  * published by the Free Software Foundation.
iklam@7089:  *
iklam@7089:  * This code is distributed in the hope that it will be useful, but WITHOUT
iklam@7089:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
iklam@7089:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
iklam@7089:  * version 2 for more details (a copy is included in the LICENSE file that
iklam@7089:  * accompanied this code).
iklam@7089:  *
iklam@7089:  * You should have received a copy of the GNU General Public License version
iklam@7089:  * 2 along with this work; if not, write to the Free Software Foundation,
iklam@7089:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
iklam@7089:  *
iklam@7089:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
iklam@7089:  * or visit www.oracle.com if you need additional information or have any
iklam@7089:  * questions.
iklam@7089:  *
iklam@7089:  */
iklam@7089: 
iklam@7089: #ifndef SHARE_VM_CLASSFILE_SHAREDPATHSMISCINFO_HPP
iklam@7089: #define SHARE_VM_CLASSFILE_SHAREDPATHSMISCINFO_HPP
iklam@7089: 
iklam@7089: #include "runtime/os.hpp"
iklam@7089: 
iklam@7089: // During dumping time, when processing class paths, we build up the dump-time
iklam@7089: // classpath. The JAR files that exist are stored in the list ClassLoader::_first_entry.
iklam@7089: // However, we need to store other "misc" information for run-time checking, such as
iklam@7089: //
iklam@7089: // + The values of Arguments::get_sysclasspath() used during dumping.
iklam@7089: //
iklam@7089: // + The meta-index file(s) used during dumping (incl modification time and size)
iklam@7089: //
iklam@7089: // + The class path elements specified during dumping but did not exist --
iklam@7089: //   these elements must also be specified at run time, and they also must not
iklam@7089: //   exist at run time.
iklam@7089: //
iklam@7089: // These misc items are stored in a linear buffer in SharedPathsMiscInfo.
iklam@7089: // The storage format is stream oriented to minimize its size.
iklam@7089: //
iklam@7089: // When writing the information to the archive file, SharedPathsMiscInfo is stored in
iklam@7089: // the archive file header. At run-time, this information is used only during initialization
iklam@7089: // (accessed using read() instead of mmap()), and is deallocated afterwards to save space.
iklam@7089: //
iklam@7089: // The SharedPathsMiscInfo class is used for both creating the the information (during
iklam@7089: // dumping time) and validation (at run time). Different constructors are used in the
iklam@7089: // two situations. See below.
iklam@7089: 
iklam@7089: class SharedPathsMiscInfo : public CHeapObj<mtClass> {
iklam@7089: protected:
iklam@7089:   char* _buf_start;
iklam@7089:   char* _cur_ptr;
iklam@7089:   char* _end_ptr;
iklam@7089:   int   _buf_size;
iklam@7089:   bool  _allocated;   // was _buf_start allocated by me?
iklam@7089:   void ensure_size(size_t needed_bytes);
iklam@7089:   void add_path(const char* path, int type);
iklam@7089: 
iklam@7089:   void write(const void* ptr, size_t size);
iklam@7089:   bool read(void* ptr, size_t size);
iklam@7089: 
iklam@7089:   static void trace_class_path(const char* msg, const char* name = NULL) {
ccheung@8184:     ClassLoader::trace_class_path(tty, msg, name);
iklam@7089:   }
iklam@7089: protected:
iklam@7089:   static bool fail(const char* msg, const char* name = NULL);
iklam@7089:   virtual bool check(jint type, const char* path);
iklam@7089: 
iklam@7089: public:
iklam@7089:   enum {
iklam@7089:     INITIAL_BUF_SIZE = 128
iklam@7089:   };
iklam@7089:   // This constructor is used when creating the misc information (during dump)
iklam@7089:   SharedPathsMiscInfo() {
iklam@7089:     _buf_size = INITIAL_BUF_SIZE;
iklam@7089:     _cur_ptr = _buf_start = NEW_C_HEAP_ARRAY(char, _buf_size, mtClass);
iklam@7089:     _allocated = true;
iklam@7089:   }
iklam@7089:   // This constructor is used when validating the misc info (during run time)
iklam@7089:   SharedPathsMiscInfo(char *buff, int size) {
iklam@7089:     _cur_ptr = _buf_start = buff;
iklam@7089:     _end_ptr = _buf_start + size;
iklam@7089:     _buf_size = size;
iklam@7089:     _allocated = false;
iklam@7089:   }
iklam@7089:   ~SharedPathsMiscInfo() {
iklam@7089:     if (_allocated) {
iklam@7089:       FREE_C_HEAP_ARRAY(char, _buf_start, mtClass);
iklam@7089:     }
iklam@7089:   }
iklam@7089:   int get_used_bytes() {
iklam@7089:     return _cur_ptr - _buf_start;
iklam@7089:   }
iklam@7089:   void* buffer() {
iklam@7089:     return _buf_start;
iklam@7089:   }
iklam@7089: 
iklam@7089:   // writing --
iklam@7089: 
iklam@7089:   // The path must not exist at run-time
iklam@7089:   void add_nonexist_path(const char* path) {
iklam@7089:     add_path(path, NON_EXIST);
iklam@7089:   }
iklam@7089: 
iklam@7089:   // The path must exist and have required size and modification time
iklam@7089:   void add_required_file(const char* path) {
iklam@7089:     add_path(path, REQUIRED);
iklam@7089: 
iklam@7089:     struct stat st;
iklam@7089:     if (os::stat(path, &st) != 0) {
iklam@7089:       assert(0, "sanity");
iklam@7089:       ClassLoader::exit_with_path_failure("failed to os::stat(%s)", path); // should not happen
iklam@7089:     }
iklam@7089:     write_time(st.st_mtime);
iklam@7089:     write_long(st.st_size);
iklam@7089:   }
iklam@7089: 
iklam@7089:   // The path must exist, and must contain exactly <num_entries> files/dirs
iklam@7089:   void add_boot_classpath(const char* path) {
iklam@7089:     add_path(path, BOOT);
iklam@7089:   }
iklam@7089:   int write_jint(jint num) {
iklam@7089:     write(&num, sizeof(num));
iklam@7089:     return 0;
iklam@7089:   }
iklam@7089:   void write_time(time_t t) {
iklam@7089:     write(&t, sizeof(t));
iklam@7089:   }
iklam@7089:   void write_long(long l) {
iklam@7089:     write(&l, sizeof(l));
iklam@7089:   }
iklam@7089: 
iklam@7089:   bool dump_to_file(int fd) {
iklam@7089:     int n = get_used_bytes();
iklam@7089:     return (os::write(fd, _buf_start, n) == (size_t)n);
iklam@7089:   }
iklam@7089: 
iklam@7089:   // reading --
iklam@7089: 
iklam@7089:   enum {
iklam@7089:     BOOT      = 1,
iklam@7089:     NON_EXIST = 2,
iklam@7089:     REQUIRED  = 3
iklam@7089:   };
iklam@7089: 
iklam@7089:   virtual const char* type_name(int type) {
iklam@7089:     switch (type) {
iklam@7089:     case BOOT:      return "BOOT";
iklam@7089:     case NON_EXIST: return "NON_EXIST";
iklam@7089:     case REQUIRED:  return "REQUIRED";
iklam@7089:     default:        ShouldNotReachHere(); return "?";
iklam@7089:     }
iklam@7089:   }
iklam@7089: 
iklam@7089:   virtual void print_path(outputStream* out, int type, const char* path) {
iklam@7089:     switch (type) {
iklam@7089:     case BOOT:
iklam@7089:       out->print("Expecting -Dsun.boot.class.path=%s", path);
iklam@7089:       break;
iklam@7089:     case NON_EXIST:
iklam@7089:       out->print("Expecting that %s does not exist", path);
iklam@7089:       break;
iklam@7089:     case REQUIRED:
iklam@7090:       out->print("Expecting that file %s must exist and is not altered", path);
iklam@7089:       break;
iklam@7089:     default:
iklam@7089:       ShouldNotReachHere();
iklam@7089:     }
iklam@7089:   }
iklam@7089: 
iklam@7089:   bool check();
iklam@7089:   bool read_jint(jint *ptr) {
iklam@7089:     return read(ptr, sizeof(jint));
iklam@7089:   }
iklam@7089:   bool read_long(long *ptr) {
iklam@7089:     return read(ptr, sizeof(long));
iklam@7089:   }
iklam@7089:   bool read_time(time_t *ptr) {
iklam@7089:     return read(ptr, sizeof(time_t));
iklam@7089:   }
iklam@7089: };
iklam@7089: 
iklam@7089: #endif // SHARE_VM_CLASSFILE_SHAREDPATHSMISCINFO_HPP