1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84

// Copyright 2018 astonbitecode
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
use std::os::raw::c_void;
use std::path::MAIN_SEPARATOR;

use java_locator::{get_jvm_dyn_lib_file_name, locate_jvm_dyn_library};
use jni_sys::{
    JavaVM,
    jclass,
    jint,
    JNIEnv,
    jsize,
};
use libloading;

use crate::{utils, errors};
use crate::errors::opt_to_res;

type JNIGetCreatedJavaVMs = unsafe extern "system" fn(vmBuf: *mut *mut JavaVM, bufLen: jsize, nVMs: *mut jsize) -> jint;

type JNICreateJavaVM = unsafe extern "system" fn(
    pvm: *mut *mut JavaVM,
    penv: *mut *mut c_void,
    args: *mut c_void,
) -> jint;

lazy_static! {
    static ref JVM_LIB: libloading::Library = {
        let full_path = format!("{}{}{}",
            locate_jvm_dyn_library().expect("Could find the jvm dynamic library"),
            MAIN_SEPARATOR,
            get_jvm_dyn_lib_file_name()
        );
        libloading::Library::new(full_path).expect("Could not load the jvm dynamic library")
    };

    static ref GET_CREATED_JVMS: libloading::Symbol<'static, JNIGetCreatedJavaVMs> = unsafe {
        JVM_LIB.get(b"JNI_GetCreatedJavaVMs").expect("Could not find symbol: JNI_GetCreatedJavaVMs")
    };

    static ref CREATE_JVM: libloading::Symbol<'static, JNICreateJavaVM> = unsafe {
        JVM_LIB.get(b"JNI_CreateJavaVM").expect("Could not find symbol: JNI_CreateJavaVM")
    };
}

pub(crate) fn get_created_java_vms(vm_buf: &mut Vec<*mut JavaVM>, buf_len: jsize, n_vms: *mut jsize) -> jint {
    unsafe {
        GET_CREATED_JVMS(vm_buf.as_mut_ptr(), buf_len, n_vms)
    }
}

pub(crate) fn create_java_vm(
    jvm: *mut *mut JavaVM,
    penv: *mut *mut c_void,
    args: *mut c_void,
) -> jint {
    unsafe {
        CREATE_JVM(jvm, penv, args)
    }
}

pub(crate) fn find_class(env: *mut JNIEnv, classname: &str) -> errors::Result<jclass> {
    unsafe {
        let cstr = utils::to_c_string(classname);
        let fc = opt_to_res((**env).FindClass)?;
        let jc = (fc)(
            env,
            cstr,
        );
        utils::drop_c_string(cstr);
        Ok(jc)
    }
}