/*

 * Copyright (c) 2014, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "classfile/classLoader.hpp"

#include "classfile/sharedPathsMiscInfo.hpp"

#include "logging/log.hpp"

#include "logging/logStream.hpp"

#include "memory/allocation.inline.hpp"

#include "memory/filemap.hpp"

#include "memory/metaspaceShared.hpp"

#include "memory/resourceArea.hpp"

#include "runtime/arguments.hpp"

#include "runtime/os.inline.hpp"

#include "utilities/ostream.hpp"

SharedPathsMiscInfo::SharedPathsMiscInfo() {

  _app_offset = 0;

  _buf_size = INITIAL_BUF_SIZE;

  _cur_ptr = _buf_start = NEW_C_HEAP_ARRAY(char, _buf_size, mtClass);

  _allocated = true;

}

SharedPathsMiscInfo::~SharedPathsMiscInfo() {

  if (_allocated) {

    FREE_C_HEAP_ARRAY(char, _buf_start);

  }

}

void SharedPathsMiscInfo::add_path(const char* path, int type) {

  log_info(class, path)("type=%s ", type_name(type));

  ClassLoader::trace_class_path("add misc shared path ", path);

  write(path, strlen(path) + 1);

  write_jint(jint(type));

}

void SharedPathsMiscInfo::ensure_size(size_t needed_bytes) {

  assert(_allocated, "cannot modify buffer during validation.");

  int used = get_used_bytes();

  int target = used + int(needed_bytes);

  if (target > _buf_size) {

    _buf_size = _buf_size * 2 + (int)needed_bytes;

    _buf_start = REALLOC_C_HEAP_ARRAY(char, _buf_start, _buf_size, mtClass);

    _cur_ptr = _buf_start + used;

    _end_ptr = _buf_start + _buf_size;

  }

}

void SharedPathsMiscInfo::write(const void* ptr, size_t size) {

  ensure_size(size);

  memcpy(_cur_ptr, ptr, size);

  _cur_ptr += size;

}

bool SharedPathsMiscInfo::read(void* ptr, size_t size) {

  if (_cur_ptr + size <= _end_ptr) {

    memcpy(ptr, _cur_ptr, size);

    _cur_ptr += size;

    return true;

  }

  return false;

}

bool SharedPathsMiscInfo::fail(const char* msg, const char* name) {

  ClassLoader::trace_class_path(msg, name);

  MetaspaceShared::set_archive_loading_failed();

  return false;

}

void SharedPathsMiscInfo::print_path(outputStream* out, int type, const char* path) {

  switch (type) {

  case BOOT_PATH:

    out->print("Expecting BOOT path=%s", path);

    break;

  case NON_EXIST:

    out->print("Expecting that %s does not exist", path);

    break;

  case APP_PATH:

    ClassLoader::trace_class_path("Expecting -Djava.class.path=", path);

    break;

  default:

    ShouldNotReachHere();

  }

}

bool SharedPathsMiscInfo::check() {

  // The whole buffer must be 0 terminated so that we can use strlen and strcmp

  // without fear.

  _end_ptr -= sizeof(jint);

  if (_cur_ptr >= _end_ptr) {

    return fail("Truncated archive file header");

  }

  if (*_end_ptr != 0) {

    return fail("Corrupted archive file header");

  }

  while (_cur_ptr < _end_ptr) {

    jint type;

    const char* path = _cur_ptr;

    _cur_ptr += strlen(path) + 1;

    if (!read_jint(&type)) {

      return fail("Corrupted archive file header");

    }

    LogTarget(Info, class, path) lt;

    if (lt.is_enabled()) {

      lt.print("type=%s ", type_name(type));

      LogStream ls(lt);

      print_path(&ls, type, path);

      ls.cr();

    }

    if (!check(type, path)) {

      if (!PrintSharedArchiveAndExit) {

        return false;

      }

    } else {

      ClassLoader::trace_class_path("ok");

    }

  }

  return true;

}

char* skip_first_path_entry(const char* path) {

  size_t path_sep_len = strlen(os::path_separator());

  char* p = strstr((char*)path, os::path_separator());

  if (p != NULL) {

    debug_only( {

      size_t image_name_len = strlen(MODULES_IMAGE_NAME);

      assert(strncmp(p - image_name_len, MODULES_IMAGE_NAME, image_name_len) == 0,

             "first entry must be the modules image");

    } );

    p += path_sep_len;

  } else {

    debug_only( {

      assert(ClassLoader::string_ends_with(path, MODULES_IMAGE_NAME),

             "first entry must be the modules image");

    } );

  }

  return p;

}

bool SharedPathsMiscInfo::check(jint type, const char* path) {

  assert(UseSharedSpaces, "runtime only");

  switch (type) {

  case BOOT_PATH:

    {

      //

      // - Archive contains boot classes only - relaxed boot path check:

      //   Extra path elements appended to the boot path at runtime are allowed.

      //

      // - Archive contains application or platform classes - strict boot path check:

      //   Validate the entire runtime boot path, which must be compactible

      //   with the dump time boot path. Appending boot path at runtime is not

      //   allowed.

      //

      // The first entry in boot path is the modules_image (guaranteed by

      // ClassLoader::setup_boot_search_path()). Skip the first entry. The

      // path of the runtime modules_image may be different from the dump

      // time path (e.g. the JDK image is copied to a different location

      // after generating the shared archive), which is acceptable. For most

      // common cases, the dump time boot path might contain modules_image only.

      char* runtime_boot_path = Arguments::get_sysclasspath();

      char* rp = skip_first_path_entry(runtime_boot_path);

      char* dp = skip_first_path_entry(path);

      bool relaxed_check = !FileMapInfo::current_info()->header()->has_platform_or_app_classes();

      if (dp == NULL && rp == NULL) {

        break;   // ok, both runtime and dump time boot paths have modules_images only

      } else if (dp == NULL && rp != NULL && relaxed_check) {

        break;   // ok, relaxed check, runtime has extra boot append path entries

      } else if (dp != NULL && rp != NULL) {

        size_t num;

        size_t dp_len = strlen(dp);

        size_t rp_len = strlen(rp);

        if (rp_len >= dp_len) {

          if (relaxed_check) {

            // only check the leading entries in the runtime boot path, up to

            // the length of the dump time boot path

            num = dp_len;

          } else {

            // check the full runtime boot path, must match with dump time

            num = rp_len;

          }

          if (os::file_name_strncmp(dp, rp, num) == 0) {

            // make sure it is the end of an entry in the runtime boot path

            if (rp[dp_len] == '\0' || rp[dp_len] == os::path_separator()[0]) {

              break; // ok, runtime and dump time paths match

            }

          }

        }

      }

      // The paths are different

      return fail("[BOOT classpath mismatch, actual =", runtime_boot_path);

    }

    break;

  case NON_EXIST:

    {

      struct stat st;

      if (os::stat(path, &st) == 0) {

        // The file actually exists

        // But we want it to not exist -> fail

        return fail("File must not exist");

      }

    }

    break;

  case APP_PATH:

    {

      size_t len = strlen(path);

      const char *appcp = Arguments::get_appclasspath();

      assert(appcp != NULL, "NULL app classpath");

      size_t appcp_len = strlen(appcp);

      if (appcp_len < len) {

        return fail("Run time APP classpath is shorter than the one at dump time: ", appcp);

      }

      // Prefix is OK: E.g., dump with -cp foo.jar, but run with -cp foo.jar:bar.jar.

      if (os::file_name_strncmp(path, appcp, len) != 0) {

        return fail("[APP classpath mismatch, actual: -Djava.class.path=", appcp);

      }

      if (appcp[len] != '\0' && appcp[len] != os::path_separator()[0]) {

        return fail("Dump time APP classpath is not a proper prefix of run time APP classpath: ", appcp);

      }

    }

    break;

  default:

    return fail("Corrupted archive file header");

  }

  return true;

}