libGetNamedModuleTest.c revision 12723:afedee84773e 
1/*
2 * Copyright (c) 2016, 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#include <stdio.h>
25#include <string.h>
26#include "jvmti.h"
27
28#ifdef __cplusplus
29extern "C" {
30#endif
31
32#ifndef JNI_ENV_ARG
33
34#ifdef __cplusplus
35#define JNI_ENV_ARG(x, y) y
36#define JNI_ENV_PTR(x) x
37#else
38#define JNI_ENV_ARG(x,y) x, y
39#define JNI_ENV_PTR(x) (*x)
40#endif
41
42#endif
43
44#define TranslateError(err) "JVMTI error"
45
46#define PASSED 0
47#define FAILED 2
48
49static const char *EXC_CNAME = "java/lang/Exception";
50static const char* MOD_CNAME = "Ljava/lang/Module;";
51
52static jvmtiEnv *jvmti = NULL;
53static jint result = PASSED;
54static jboolean printdump = JNI_FALSE;
55
56static jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved);
57
58JNIEXPORT
59jint JNICALL Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
60    return Agent_Initialize(jvm, options, reserved);
61}
62
63JNIEXPORT
64jint JNICALL Agent_OnAttach(JavaVM *jvm, char *options, void *reserved) {
65    return Agent_Initialize(jvm, options, reserved);
66}
67
68JNIEXPORT
69jint JNICALL JNI_OnLoad(JavaVM *jvm, void *reserved) {
70    return JNI_VERSION_1_8;
71}
72
73static
74jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
75    jint res;
76
77    if (options != NULL && strcmp(options, "printdump") == 0) {
78        printdump = JNI_TRUE;
79    }
80
81    res = JNI_ENV_PTR(jvm)->GetEnv(JNI_ENV_ARG(jvm, (void **) &jvmti),
82        JVMTI_VERSION_9);
83    if (res != JNI_OK || jvmti == NULL) {
84        printf("    Error: wrong result of a valid call to GetEnv!\n");
85        return JNI_ERR;
86    }
87
88    return JNI_OK;
89}
90
91static
92jint throw_exc(JNIEnv *env, char *msg) {
93    jclass exc_class = JNI_ENV_PTR(env)->FindClass(JNI_ENV_ARG(env, EXC_CNAME));
94
95    if (exc_class == NULL) {
96        printf("throw_exc: Error in FindClass(env, %s)\n", EXC_CNAME);
97        return -1;
98    }
99    return JNI_ENV_PTR(env)->ThrowNew(JNI_ENV_ARG(env, exc_class), msg);
100}
101
102static
103jobject get_class_loader(jclass cls) {
104    jvmtiError err = JVMTI_ERROR_NONE;
105    jobject loader = NULL;
106
107    if (printdump == JNI_TRUE) {
108        printf(">>> getting class loader ...\n");
109    }
110    err = (*jvmti)->GetClassLoader(jvmti, cls, &loader);
111    if (err != JVMTI_ERROR_NONE) {
112        printf("    Error in GetClassLoader: %s (%d)\n", TranslateError(err), err);
113    }
114    return loader;
115}
116
117static
118jclass jlM(JNIEnv *env) {
119    jclass cls = NULL;
120
121    cls = JNI_ENV_PTR(env)->FindClass(JNI_ENV_ARG(env, MOD_CNAME));
122    if (cls == NULL) {
123        printf("    Error in JNI FindClass: %s\n", MOD_CNAME);
124    }
125    return cls;
126}
127
128jmethodID
129get_method(JNIEnv *env, jclass clazz, const char * name, const char *sig) {
130    jmethodID method = NULL;
131
132    method = JNI_ENV_PTR(env)->GetMethodID(JNI_ENV_ARG(env, clazz), name, sig);
133    if (method == NULL) {
134        printf("    Error in JNI GetMethodID %s with signature %s", name, sig);
135    }
136    return method;
137}
138
139static
140jobject get_module_loader(JNIEnv *env, jobject module) {
141    static jmethodID cl_method = NULL;
142    jobject loader = NULL;
143
144    if (cl_method == NULL) {
145        cl_method = get_method(env, jlM(env), "getClassLoader", "()Ljava/lang/ClassLoader;");
146    }
147    loader = (jobject)JNI_ENV_PTR(env)->CallObjectMethod(JNI_ENV_ARG(env, module), cl_method);
148    return loader;
149}
150
151static
152const char* get_module_name(JNIEnv *env, jobject module) {
153    static jmethodID method = NULL;
154    jobject loader = NULL;
155    jstring jstr = NULL;
156    const char *name = NULL;
157    const char *nstr = NULL;
158
159    if (method == NULL) {
160        method = get_method(env, jlM(env), "getName", "()Ljava/lang/String;");
161    }
162    jstr = (jstring)JNI_ENV_PTR(env)->CallObjectMethod(JNI_ENV_ARG(env, module), method);
163    if (jstr != NULL) {
164        name = JNI_ENV_PTR(env)->GetStringUTFChars(JNI_ENV_ARG(env, jstr), NULL);
165    }
166    loader = get_module_loader(env, module);
167    nstr = (name == NULL) ? "<UNNAMED>" : name;
168    printf("    loader: %p, module: %p, name: %s\n", loader, module, nstr);
169    return name;
170}
171
172static
173jvmtiError get_module(JNIEnv *env,
174                      jobject loader,
175                      const char* pkg_name,
176                      jobject* module_ptr,
177                      const char** mod_name_ptr) {
178    jvmtiError err = JVMTI_ERROR_NONE;
179    const char* name = (pkg_name == NULL) ? "<NULL>" : pkg_name;
180
181    printf(">>> getting module by loader %p and package \"%s\"\n", loader, name);
182    *mod_name_ptr = NULL;
183    err = (*jvmti)->GetNamedModule(jvmti, loader, pkg_name, module_ptr);
184    if (err != JVMTI_ERROR_NONE) {
185        printf("    Error in GetNamedModule for package \"%s\": %s (%d)\n",
186               name, TranslateError(err), err);
187        return err;
188    }
189    printf("    returned module: %p\n", *module_ptr);
190    if (*module_ptr == NULL) { // named module was not found
191        return err;
192    }
193    *mod_name_ptr = get_module_name(env, *module_ptr);
194    return err;
195}
196
197static
198jint get_all_modules(JNIEnv *env) {
199    jvmtiError err;
200    jint cnt = -1;
201    jint idx = 0;
202    jobject* modules;
203
204    printf(">>> Inspecting modules with GetAllModules\n");
205    err = (*jvmti)->GetAllModules(jvmti, &cnt, &modules);
206    if (err != JVMTI_ERROR_NONE) {
207        printf("Error in GetAllModules: %d\n", err);
208        return -1;
209    }
210    for (idx = 0; idx < cnt; ++idx) {
211        get_module_name(env, modules[idx]);
212    }
213    return cnt;
214}
215
216static
217jint check_bad_loader(JNIEnv *env, jobject loader) {
218    jvmtiError err = JVMTI_ERROR_NONE;
219    jobject module = NULL;
220    const char* mod_name = NULL;
221
222    err = get_module(env, loader, "", &module, &mod_name);
223    if (err != JVMTI_ERROR_ILLEGAL_ARGUMENT) {
224        return FAILED;
225    }
226    printf("    got expected JVMTI_ERROR_ILLEGAL_ARGUMENT for bad loader\n");
227    return PASSED;
228}
229
230static
231jint check_system_loader(JNIEnv *env, jobject loader) {
232    jvmtiError err = JVMTI_ERROR_NONE;
233    jobject module = NULL;
234    const char* exp_name = NULL;
235    const char* mod_name = NULL;
236
237    // NULL pointer for package name
238    err = get_module(env, loader, NULL, &module, &mod_name);
239    if (err != JVMTI_ERROR_NULL_POINTER) {
240        throw_exc(env, "check #SN1: failed to return JVMTI_ERROR_NULL_POINTER for NULL package");
241        return FAILED;
242    }
243
244    // NULL pointer for module_ptr
245    err = (*jvmti)->GetNamedModule(jvmti, loader, "", NULL);
246    if (err != JVMTI_ERROR_NULL_POINTER) {
247        throw_exc(env, "check #SN2: failed to return JVMTI_ERROR_NULL_POINTER for NULL module_ptr");
248        return FAILED;
249    }
250
251    // Unnamed/default package ""
252    err = get_module(env, loader, "", &module, &mod_name);
253    if (err != JVMTI_ERROR_NONE) {
254        throw_exc(env, "check #S1: failed to return JVMTI_ERROR_NONE for default package");
255        return FAILED;
256    }
257    if (module != NULL || mod_name != NULL) {
258        throw_exc(env, "check #S2: failed to return NULL-module for default package");
259        return FAILED;
260    }
261
262    // Test package: MyPackage
263    err = get_module(env, loader, "MyPackage", &module, &mod_name);
264    if (err != JVMTI_ERROR_NONE) {
265        throw_exc(env, "check #S3: failed to return JVMTI_ERROR_NONE for MyPackage");
266        return FAILED;
267    }
268    if (module != NULL || mod_name != NULL) {
269        throw_exc(env, "check #S4: failed to return NULL-module for MyPackage");
270        return FAILED;
271    }
272
273    // Package: com/sun/jdi
274    exp_name = "jdk.jdi";
275    err = get_module(env, loader, "com/sun/jdi", &module, &mod_name);
276    if (err != JVMTI_ERROR_NONE) {
277        throw_exc(env, "check #S5: failed to return JVMTI_ERROR_NONE for test package");
278        return FAILED;
279    }
280    if (module == NULL || mod_name == NULL) {
281        throw_exc(env, "check #S6: failed to return named module for com/sun/jdi package");
282        return FAILED;
283    }
284    if (strcmp(mod_name, exp_name) != 0) {
285        printf("check #S7: failed to return right module, expected: %s, returned: %s\n",
286               exp_name, mod_name);
287        throw_exc(env, "check #S7: failed to return jdk.jdi module for com/sun/jdi package");
288        return FAILED;
289    }
290
291    // Non-existing package: "bad/package/name"
292    err = get_module(env, loader, "bad/package/name", &module, &mod_name);
293    if (err != JVMTI_ERROR_NONE) {
294        throw_exc(env, "check #S8: failed to return JVMTI_ERROR_NONE for bad package");
295        return FAILED;
296    }
297    if (module != NULL || mod_name != NULL) {
298        throw_exc(env, "check #S9: failed to return NULL-module for bad package");
299        return FAILED;
300    }
301    return PASSED;
302}
303
304static
305jint check_bootstrap_loader(JNIEnv *env, jobject loader) {
306    jvmtiError err = JVMTI_ERROR_NONE;
307    jobject module = NULL;
308    const char* exp_name = NULL;
309    const char* mod_name = NULL;
310
311    // NULL pointer for package name
312    err = get_module(env, loader, NULL, &module, &mod_name);
313    if (err != JVMTI_ERROR_NULL_POINTER) {
314        throw_exc(env, "check #BN1: failed to return JVMTI_ERROR_NULL_POINTER for NULL package");
315        return FAILED;
316    }
317
318    // NULL pointer for module_ptr
319    err = (*jvmti)->GetNamedModule(jvmti, loader, "", NULL);
320    if (err != JVMTI_ERROR_NULL_POINTER) {
321        throw_exc(env, "check #BN2: failed to return JVMTI_ERROR_NULL_POINTER for NULL module_ptr");
322        return FAILED;
323    }
324
325    // Unnamed/default package ""
326    err = get_module(env, loader, "", &module, &mod_name);
327    if (err != JVMTI_ERROR_NONE) {
328        throw_exc(env, "check #B1: failed to return JVMTI_ERROR_NONE for default package");
329        return FAILED;
330    }
331    if (module != NULL || mod_name != NULL) {
332        throw_exc(env, "check #B2: failed to return NULL-module for default package");
333        return FAILED;
334    }
335
336    // Normal package from java.base module: "java/lang"
337    exp_name = "java.base";
338    err = get_module(env, loader, "java/lang", &module, &mod_name);
339    if (err != JVMTI_ERROR_NONE) {
340        throw_exc(env, "check #B3: failed to return JVMTI_ERROR_NONE for java/lang package");
341        return FAILED;
342    }
343    if (module == NULL || mod_name == NULL) {
344        throw_exc(env, "check #B4: failed to return named module for java/lang package");
345        return FAILED;
346    }
347    if (strcmp(exp_name, mod_name) != 0) {
348        printf("check #B5: failed to return right module, expected: %s, returned: %s\n",
349               exp_name, mod_name);
350        throw_exc(env, "check #B5: failed to return expected module for java/lang package");
351        return FAILED;
352    }
353
354    // Non-existing package: "bad/package/name"
355    err = get_module(env, loader, "bad/package/name", &module, &mod_name);
356    if (err != JVMTI_ERROR_NONE) {
357        throw_exc(env, "check #B6: failed to return JVMTI_ERROR_NONE for bad package");
358        return FAILED;
359    }
360    if (module != NULL || mod_name != NULL) {
361        throw_exc(env, "check #B7: failed to return NULL-module for bad package");
362        return FAILED;
363    }
364    return PASSED;
365}
366
367JNIEXPORT jint JNICALL
368Java_MyPackage_GetNamedModuleTest_check(JNIEnv *env, jclass cls) {
369    jobject loader = NULL;
370
371    if (jvmti == NULL) {
372        throw_exc(env, "JVMTI client was not properly loaded!\n");
373        return FAILED;
374    }
375
376    get_all_modules(env);
377
378    printf("\n*** Check for bad ClassLoader ***\n\n");
379    result = check_bad_loader(env, (jobject)cls);
380    if (result != PASSED) {
381        throw_exc(env, "check #L1: failed to return JVMTI_ERROR_ILLEGAL_ARGUMENT for bad loader");
382        return result;
383    }
384
385    loader = get_class_loader(cls);
386    if (loader == NULL) {
387        throw_exc(env, "check #L2: failed to return non-NULL loader for valid test class");
388        return FAILED;
389    }
390
391    printf("\n*** Checks for System ClassLoader ***\n\n");
392    result = check_system_loader(env, loader);
393    if (result != PASSED) {
394        return result;
395    }
396
397    printf("\n*** Checks for Bootstrap ClassLoader ***\n\n");
398    result = check_bootstrap_loader(env, NULL);
399
400    return result;
401}
402
403#ifdef __cplusplus
404}
405#endif
406