1/*
2 * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#include "precompiled.hpp"
26#include "prims/jvm.h"
27#include "runtime/arguments.hpp"
28#include "runtime/os.hpp"
29#include "decoder_windows.hpp"
30#include "windbghelp.hpp"
31
32WindowsDecoder::WindowsDecoder() {
33  _can_decode_in_vm = true;
34  _decoder_status = no_error;
35  initialize();
36}
37
38void WindowsDecoder::initialize() {
39  if (!has_error()) {
40    HANDLE hProcess = ::GetCurrentProcess();
41    WindowsDbgHelp::symSetOptions(SYMOPT_UNDNAME | SYMOPT_DEFERRED_LOADS | SYMOPT_EXACT_SYMBOLS);
42    if (!WindowsDbgHelp::symInitialize(hProcess, NULL, TRUE)) {
43      _decoder_status = helper_init_error;
44      return;
45    }
46
47    // set pdb search paths
48    char paths[MAX_PATH];
49    int  len = sizeof(paths);
50    if (!WindowsDbgHelp::symGetSearchPath(hProcess, paths, len)) {
51      paths[0] = '\0';
52    } else {
53      // available spaces in path buffer
54      len -= (int)strlen(paths);
55    }
56
57    char tmp_path[MAX_PATH];
58    DWORD dwSize;
59    HMODULE hJVM = ::GetModuleHandle("jvm.dll");
60    tmp_path[0] = '\0';
61    // append the path where jvm.dll is located
62    if (hJVM != NULL && (dwSize = ::GetModuleFileName(hJVM, tmp_path, sizeof(tmp_path))) > 0) {
63      while (dwSize > 0 && tmp_path[dwSize] != '\\') {
64        dwSize --;
65      }
66
67      tmp_path[dwSize] = '\0';
68
69      if (dwSize > 0 && len > (int)dwSize + 1) {
70        strncat(paths, os::path_separator(), 1);
71        strncat(paths, tmp_path, dwSize);
72        len -= dwSize + 1;
73      }
74    }
75
76    // append $JRE/bin. Arguments::get_java_home actually returns $JRE
77    // path
78    char *p = Arguments::get_java_home();
79    assert(p != NULL, "empty java home");
80    size_t java_home_len = strlen(p);
81    if (len > (int)java_home_len + 5) {
82      strncat(paths, os::path_separator(), 1);
83      strncat(paths, p, java_home_len);
84      strncat(paths, "\\bin", 4);
85      len -= (int)(java_home_len + 5);
86    }
87
88    // append $JDK/bin path if it exists
89    assert(java_home_len < MAX_PATH, "Invalid path length");
90    // assume $JRE is under $JDK, construct $JDK/bin path and
91    // see if it exists or not
92    if (strncmp(&p[java_home_len - 3], "jre", 3) == 0) {
93      strncpy(tmp_path, p, java_home_len - 3);
94      tmp_path[java_home_len - 3] = '\0';
95      strncat(tmp_path, "bin", 3);
96
97      // if the directory exists
98      DWORD dwAttrib = GetFileAttributes(tmp_path);
99      if (dwAttrib != INVALID_FILE_ATTRIBUTES &&
100          (dwAttrib & FILE_ATTRIBUTE_DIRECTORY)) {
101        // tmp_path should have the same length as java_home_len, since we only
102        // replaced 'jre' with 'bin'
103        if (len > (int)java_home_len + 1) {
104          strncat(paths, os::path_separator(), 1);
105          strncat(paths, tmp_path, java_home_len);
106        }
107      }
108    }
109
110    WindowsDbgHelp::symSetSearchPath(hProcess, paths);
111
112    // find out if jvm.dll contains private symbols, by decoding
113    // current function and comparing the result
114    address addr = (address)Decoder::demangle;
115    char buf[MAX_PATH];
116    if (decode(addr, buf, sizeof(buf), NULL, NULL, true /* demangle */)) {
117      _can_decode_in_vm = !strcmp(buf, "Decoder::demangle");
118    }
119  }
120}
121
122void WindowsDecoder::uninitialize() {}
123
124bool WindowsDecoder::can_decode_C_frame_in_vm() const {
125  return  (!has_error() && _can_decode_in_vm);
126}
127
128
129bool WindowsDecoder::decode(address addr, char *buf, int buflen, int* offset, const char* modulepath, bool demangle_name)  {
130  if (!has_error()) {
131    PIMAGEHLP_SYMBOL64 pSymbol;
132    char symbolInfo[MAX_PATH + sizeof(IMAGEHLP_SYMBOL64)];
133    pSymbol = (PIMAGEHLP_SYMBOL64)symbolInfo;
134    pSymbol->MaxNameLength = MAX_PATH;
135    pSymbol->SizeOfStruct = sizeof(IMAGEHLP_SYMBOL64);
136    DWORD64 displacement;
137    if (WindowsDbgHelp::symGetSymFromAddr64(::GetCurrentProcess(), (DWORD64)addr, &displacement, pSymbol)) {
138      if (buf != NULL) {
139        if (!(demangle_name && demangle(pSymbol->Name, buf, buflen))) {
140          jio_snprintf(buf, buflen, "%s", pSymbol->Name);
141        }
142      }
143      if(offset != NULL) *offset = (int)displacement;
144      return true;
145    }
146  }
147  if (buf != NULL && buflen > 0) buf[0] = '\0';
148  if (offset != NULL) *offset = -1;
149  return false;
150}
151
152bool WindowsDecoder::demangle(const char* symbol, char *buf, int buflen) {
153  if (!has_error()) {
154    return WindowsDbgHelp::unDecorateSymbolName(symbol, buf, buflen, UNDNAME_COMPLETE) > 0;
155  }
156  return false;
157}
158
159