1 /*
   2  * Copyright (c) 2004, 2018, 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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <windows.h>
  29 #include <locale.h>
  30 
  31 #include "jni.h"
  32 #include "jni_util.h"
  33 
  34 static void getParent(const TCHAR *path, TCHAR *dest) {
  35     char* lastSlash = max(strrchr(path, '\\'), strrchr(path, '/'));
  36     if (lastSlash == NULL) {
  37         *dest = 0;
  38         return;
  39     }
  40     if (path != dest)
  41         strcpy(dest, path);
  42     *lastSlash = 0;
  43 }
  44 
  45 void* getProcessHandle() {
  46     return (void*)GetModuleHandle(NULL);
  47 }
  48 
  49 /*
  50  * Windows symbols can be simple like JNI_OnLoad or __stdcall format
  51  * like _JNI_OnLoad@8. We need to handle both.
  52  */
  53 void buildJniFunctionName(const char *sym, const char *cname,
  54                           char *jniEntryName) {
  55     if (cname != NULL) {
  56         char *p = strrchr(sym, '@');
  57         if (p != NULL && p != sym) {
  58             // sym == _JNI_OnLoad@8
  59             strncpy(jniEntryName, sym, (p - sym));
  60             jniEntryName[(p-sym)] = '\0';
  61             // jniEntryName == _JNI_OnLoad
  62             strcat(jniEntryName, "_");
  63             strcat(jniEntryName, cname);
  64             strcat(jniEntryName, p);
  65             //jniEntryName == _JNI_OnLoad_cname@8
  66         } else {
  67             strcpy(jniEntryName, sym);
  68             strcat(jniEntryName, "_");
  69             strcat(jniEntryName, cname);
  70         }
  71     } else {
  72         strcpy(jniEntryName, sym);
  73     }
  74     return;
  75 }
  76 
  77 JNIEXPORT size_t JNICALL
  78 getLastErrorString(char *utf8_jvmErrorMsg, size_t cbErrorMsg)
  79 {
  80     size_t n = 0;
  81     if (cbErrorMsg > 0) {
  82         BOOLEAN noError = FALSE;
  83         WCHAR *utf16_osErrorMsg = (WCHAR *)malloc(cbErrorMsg*sizeof(WCHAR));
  84         if (utf16_osErrorMsg == NULL) {
  85             // OOM accident
  86             strncpy(utf8_jvmErrorMsg, "Out of memory", cbErrorMsg);
  87             // truncate if too long
  88             utf8_jvmErrorMsg[cbErrorMsg - 1] = '\0';
  89             n = strlen(utf8_jvmErrorMsg);
  90         } else {
  91             DWORD errval = GetLastError();
  92             if (errval != 0) {
  93                 // WIN32 error
  94                 n = (size_t)FormatMessageW(
  95                     FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS,
  96                     NULL,
  97                     errval,
  98                     0,
  99                     utf16_osErrorMsg,
 100                     (DWORD)cbErrorMsg,
 101                     NULL);
 102                 if (n > 3) {
 103                     // Drop final '.', CR, LF
 104                     if (utf16_osErrorMsg[n - 1] == L'\n') --n;
 105                     if (utf16_osErrorMsg[n - 1] == L'\r') --n;
 106                     if (utf16_osErrorMsg[n - 1] == L'.') --n;
 107                     utf16_osErrorMsg[n] = L'\0';
 108                 }
 109             } else if (errno != 0) {
 110                 // C runtime error that has no corresponding WIN32 error code
 111                 int ret = _wcserror_s(utf16_osErrorMsg, cbErrorMsg, errno);
 112                 if (ret == 0)
 113                     n = wcslen(utf16_osErrorMsg);
 114             } else
 115                 noError = TRUE; //OS has no error to report
 116 
 117             if (!noError) {
 118                 if (n > 0) {
 119                     n = WideCharToMultiByte(
 120                         CP_UTF8,
 121                         0,
 122                         utf16_osErrorMsg,
 123                         (int)n,
 124                         utf8_jvmErrorMsg,
 125                         (int)cbErrorMsg,
 126                         NULL,
 127                         NULL);
 128 
 129                     // no way to die
 130                     if (n > 0)
 131                         utf8_jvmErrorMsg[min(cbErrorMsg - 1, n)] = '\0';
 132                 }
 133 
 134                 if (n <= 0) {
 135                     strncpy(utf8_jvmErrorMsg, "Secondary error while OS message extraction", cbErrorMsg);
 136                     // truncate if too long
 137                     utf8_jvmErrorMsg[cbErrorMsg - 1] = '\0';
 138                     n = strlen(utf8_jvmErrorMsg);
 139                 }
 140             }
 141             free(utf16_osErrorMsg);
 142         }
 143     }
 144     return n;
 145 }
 146 
 147 JNIEXPORT int JNICALL
 148 getErrorString(int err, char *buf, size_t len)
 149 {
 150     int ret = 0;
 151     if (err == 0 || len < 1) return 0;
 152     ret = strerror_s(buf, len, err);
 153     return ret;
 154 }