1 /*
   2  * Copyright (c) 1998, 2012, 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 /*
  27  * Adapted from JDK 1.2 linker_md.c v1.37. Note that we #define
  28  * NATIVE here, whether or not we're running solaris native threads.
  29  * Outside the VM, it's unclear how we can do the locking that is
  30  * done in the green threads version of the code below.
  31  */
  32 #define NATIVE
  33 
  34 /*
  35  * Machine Dependent implementation of the dynamic linking support
  36  * for java.  This routine is Solaris specific.
  37  */
  38 
  39 #include <stdio.h>
  40 #include <dlfcn.h>
  41 #include <unistd.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44 
  45 #include "path_md.h"
  46 #ifndef NATIVE
  47 #include "iomgr.h"
  48 #include "threads_md.h"
  49 #endif
  50 
  51 #ifdef __APPLE__
  52 #define LIB_SUFFIX "dylib"
  53 #else
  54 #define LIB_SUFFIX "so"
  55 #endif
  56 
  57 static void dll_build_name(char* buffer, size_t buflen,
  58                            const char* pname, const char* fname) {
  59     // Based on os_solaris.cpp
  60 
  61     char *path_sep = PATH_SEPARATOR;
  62     char *pathname = (char *)pname;
  63     *buffer = '\0';
  64     while (strlen(pathname) > 0) {
  65         char *p = strchr(pathname, *path_sep);
  66         if (p == NULL) {
  67             p = pathname + strlen(pathname);
  68         }
  69         /* check for NULL path */
  70         if (p == pathname) {
  71             continue;
  72         }
  73         (void)snprintf(buffer, buflen, "%.*s/lib%s." LIB_SUFFIX, (int)(p - pathname),
  74                        pathname, fname);
  75 
  76         if (access(buffer, F_OK) == 0) {
  77             break;
  78         }
  79         if (*p == '\0') {
  80             pathname = p;
  81         } else {
  82             pathname = p + 1;
  83         }
  84         *buffer = '\0';
  85     }
  86 }
  87 
  88 /*
  89  * create a string for the JNI native function name by adding the
  90  * appropriate decorations.
  91  */
  92 int
  93 dbgsysBuildFunName(char *name, int nameLen, int args_size, int encodingIndex)
  94 {
  95   /* On Solaris, there is only one encoding method. */
  96     if (encodingIndex == 0)
  97         return 1;
  98     return 0;
  99 }
 100 
 101 /*
 102  * create a string for the dynamic lib open call by adding the
 103  * appropriate pre and extensions to a filename and the path
 104  */
 105 void
 106 dbgsysBuildLibName(char *holder, int holderlen, char *pname, char *fname)
 107 {
 108     const int pnamelen = pname ? strlen(pname) : 0;
 109 
 110     *holder = '\0';
 111     /* Quietly truncate on buffer overflow.  Should be an error. */
 112     if (pnamelen + (int)strlen(fname) + 10 > holderlen) {
 113         return;
 114     }
 115 
 116     if (pnamelen == 0) {
 117         (void)snprintf(holder, holderlen, "lib%s." LIB_SUFFIX, fname);
 118     } else {
 119       dll_build_name(holder, holderlen, pname, fname);
 120     }
 121 }
 122 
 123 #ifndef NATIVE
 124 extern int thr_main(void);
 125 #endif
 126 
 127 void *
 128 dbgsysLoadLibrary(const char *name, char *err_buf, int err_buflen)
 129 {
 130     void * result;
 131 #ifdef NATIVE
 132     result = dlopen(name, RTLD_LAZY);
 133 #else
 134     sysMonitorEnter(greenThreadSelf(), &_dl_lock);
 135     result = dlopen(name, RTLD_NOW);
 136     sysMonitorExit(greenThreadSelf(), &_dl_lock);
 137     /*
 138      * This is a bit of bulletproofing to catch the commonly occurring
 139      * problem of people loading a library which depends on libthread into
 140      * the VM.  thr_main() should always return -1 which means that libthread
 141      * isn't loaded.
 142      */
 143     if (thr_main() != -1) {
 144          VM_CALL(panic)("libthread loaded into green threads");
 145     }
 146 #endif
 147     if (result == NULL) {
 148         (void)strncpy(err_buf, dlerror(), err_buflen-2);
 149         err_buf[err_buflen-1] = '\0';
 150     }
 151     return result;
 152 }
 153 
 154 void dbgsysUnloadLibrary(void *handle)
 155 {
 156 #ifndef NATIVE
 157     sysMonitorEnter(greenThreadSelf(), &_dl_lock);
 158 #endif
 159     (void)dlclose(handle);
 160 #ifndef NATIVE
 161     sysMonitorExit(greenThreadSelf(), &_dl_lock);
 162 #endif
 163 }
 164 
 165 void * dbgsysFindLibraryEntry(void *handle, const char *name)
 166 {
 167     void * sym;
 168 #ifndef NATIVE
 169     sysMonitorEnter(greenThreadSelf(), &_dl_lock);
 170 #endif
 171     sym =  dlsym(handle, name);
 172 #ifndef NATIVE
 173     sysMonitorExit(greenThreadSelf(), &_dl_lock);
 174 #endif
 175     return sym;
 176 }