Name: stC104175 Date: 08/31/2000


[yw@ywlap cgi-bin]$ java -version
java version "1.3.0beta_refresh"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.0beta_refresh-b09)
Java HotSpot(TM) Client VM (build 1.3.0beta-b07, mixed mode)
[yw@ywlap cgi-bin]$

I try to embed JVM into Perl, and got this:
[yw@ywlap cgi-bin]$ perl t
Create Jvm!
#
# HotSpot Virtual Machine Error, Internal Error
# Please report this error at
# http://java.sun.com/cgi-bin/bugreport.cgi
#
# Error ID: 4F533F4C494E55580E4350500549
#
# Problematic Thread: Segmentation fault (core dumped)
[yw@ywlap cgi-bin]$

Basically, the perl script invokes C function, which load
$JDKHOME/jre/lib/i386/server/libjvm.so, and use JNI
to invoke Java VM API to access Java.

[yw@ywlap cgi-bin]$ cat t
#!/usr/bin/perl -w
use Jvm;
use Sybase::CTlib;

new Jvm();
[yw@ywlap cgi-bin]$


If take "use Sybase::CTlib" out, it works fine.
It's only has problem when use "Sybase::CTlib" module, which is from
the 3rd party. This module maybe load some other shared lib, and cause
the problem.(It can be downloaded from http://www.mbay.net/~mpeppler)

The "new Jvm()" is very simple, it's implemented in C:

JNIEnv* createJVM () {
    JNIEnv *env;
    JavaVM *jvm;
    /*JDK1_1InitArgs vm_args;*/
JavaVMInitArgs vm_args;
    jint res;
    jclass cls;
    jmethodID mid;
    jstring jstr;
    jobjectArray args;
    char classpath[1024];

    jint (JNICALL *JNI_DefaultArgs)(void*);
    jint (JNICALL *JNI_CreateVM)(const void*,const void*,void*);
    void * dl_handle;

    /* IMPORTANT: specify vm_args version # if you use JDK1.1.2 and beyond */
 
    /* vm_args.version = 0x00010002; */
    vm_args.version = JNI_VERSION_1_2;
    /* printf("ver %x\n", JNI_VERSION_1_2); */
    vm_args.ignoreUnrecognized = JNI_FALSE;
    /* vm_args.options = options; */
    vm_args.nOptions = 0;

    /*
    JNI_GetDefaultJavaVMInitArgs(&vm_args);
    */

    /* dl_handle = load_so("/home/pkgs/jdk1.3/jre/lib/i386/server/libjvm.so"); *
/
    dl_handle = load_so(g_libjvm);
    JNI_DefaultArgs = (jint (JNICALL *)(void*)) getsym (dl_handle, "JNI_GetDefau
ltJavaVMInitArgs");
    JNI_CreateVM = (jint (JNICALL *)(const void*,const void*,void*)) getsym (dl_
handle, "JNI_CreateJavaVM");

    (*JNI_DefaultArgs)(&vm_args);

    /* Create the Java VM */
    /* res = JNI_CreateJavaVM(&jvm,&env,&vm_args); */
    res = (*JNI_CreateVM)(&jvm,&env,&vm_args);
    if (res) {
        fprintf(stderr, "Can't create Java VM\n");
        exit(1);
    }

return env;
}
(Review ID: 109145)
======================================================================