1 /*
2 * Copyright (c) 2012, 2013, 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
25 #include "sun_jvm_hotspot_asm_Disassembler.h"
26
27 /*
28 * This file implements a binding between Java and the hsdis
29 * dissasembler. It should compile on Linux/Solaris and Windows.
30 * The only platform dependent pieces of the code for doing
31 * dlopen/dlsym to find the entry point in hsdis. All the rest is
32 * standard JNI code.
33 */
34
35 #ifdef _WINDOWS
36 // Disable CRT security warning against _snprintf
37 #pragma warning (disable : 4996)
38
39 #define snprintf _snprintf
40 #define vsnprintf _vsnprintf
41
42 #include <windows.h>
43 #include <sys/types.h>
44 #include <sys/stat.h>
45 #ifdef _DEBUG
46 #include <crtdbg.h>
47 #endif
48
49 #else
50
51 #include <string.h>
52 #include <dlfcn.h>
53
54 #ifndef __APPLE__
55 #include <link.h>
56 #endif
57
58 #endif
59
60 #include <limits.h>
61 #include <stdio.h>
62 #include <stdarg.h>
63 #include <stdlib.h>
64 #include <errno.h>
65
66 #ifdef _WINDOWS
67 static int getLastErrorString(char *buf, size_t len)
68 {
69 long errval;
70
71 if ((errval = GetLastError()) != 0)
72 {
73 /* DOS error */
74 size_t n = (size_t)FormatMessage(
75 FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS,
76 NULL,
77 errval,
78 0,
79 buf,
80 (DWORD)len,
81 NULL);
82 if (n > 3) {
83 /* Drop final '.', CR, LF */
84 if (buf[n - 1] == '\n') n--;
85 if (buf[n - 1] == '\r') n--;
86 if (buf[n - 1] == '.') n--;
87 buf[n] = '\0';
88 }
89 return (int)n;
90 }
91
92 if (errno != 0)
93 {
94 /* C runtime error that has no corresponding DOS error code */
95 strerror_s(buf, len, errno);
96 return strlen(buf);
97 }
98 return 0;
99 }
100 #endif /* _WINDOWS */
101
102 /*
103 * Class: sun_jvm_hotspot_asm_Disassembler
104 * Method: load_library
105 * Signature: (Ljava/lang/String;)L
106 */
107 JNIEXPORT jlong JNICALL Java_sun_jvm_hotspot_asm_Disassembler_load_1library(JNIEnv * env,
108 jclass disclass,
109 jstring jrepath_s,
110 jstring libname_s) {
111 uintptr_t func = 0;
112 const char *error_message = NULL;
113 const char *jrepath = NULL;
114 const char *libname = NULL;
115 char buffer[128];
116
117 #ifdef _WINDOWS
118 HINSTANCE hsdis_handle = (HINSTANCE) NULL;
119 #else
120 void* hsdis_handle = NULL;
121 #endif
122
123 jrepath = (*env)->GetStringUTFChars(env, jrepath_s, NULL); // like $JAVA_HOME/jre/lib/sparc/
124 if (jrepath == NULL || (*env)->ExceptionOccurred(env)) {
125 return 0;
126 }
127
128 libname = (*env)->GetStringUTFChars(env, libname_s, NULL);
129 if (libname == NULL || (*env)->ExceptionOccurred(env)) {
130 (*env)->ReleaseStringUTFChars(env, jrepath_s, jrepath);
131 return 0;
132 }
133
134 /* Load the hsdis library */
135 #ifdef _WINDOWS
136 hsdis_handle = LoadLibrary(libname);
137 if (hsdis_handle == NULL) {
138 snprintf(buffer, sizeof(buffer), "%s%s", jrepath, libname);
139 hsdis_handle = LoadLibrary(buffer);
140 }
141 if (hsdis_handle != NULL) {
142 func = (uintptr_t)GetProcAddress(hsdis_handle, "decode_instructions_virtual");
143 }
144 if (func == 0) {
145 getLastErrorString(buffer, sizeof(buffer));
146 error_message = buffer;
147 }
148 #else
149 hsdis_handle = dlopen(libname, RTLD_LAZY | RTLD_GLOBAL);
150 if (hsdis_handle == NULL) {
151 snprintf(buffer, sizeof(buffer), "%s%s", jrepath, libname);
152 hsdis_handle = dlopen(buffer, RTLD_LAZY | RTLD_GLOBAL);
153 }
154 if (hsdis_handle != NULL) {
155 func = (uintptr_t)dlsym(hsdis_handle, "decode_instructions_virtual");
156 }
157 if (func == 0) {
158 error_message = dlerror();
159 }
160 #endif
161
162 (*env)->ReleaseStringUTFChars(env, libname_s, libname);
163 (*env)->ReleaseStringUTFChars(env, jrepath_s, jrepath);
164
165 if (func == 0) {
166 /* Couldn't find entry point. error_message should contain some
167 * platform dependent error message.
168 */
169 jclass eclass = (*env)->FindClass(env, "sun/jvm/hotspot/debugger/DebuggerException");
170 if ((*env)->ExceptionOccurred(env)) {
171 /* Can't throw exception, probably OOM, so silently return 0 */
172 return (jlong) 0;
173 }
174
175 (*env)->ThrowNew(env, eclass, error_message);
176 }
177 return (jlong)func;
178 }
179
180 /* signature of decode_instructions_virtual from hsdis.h */
181 typedef void* (*decode_func)(uintptr_t start_va, uintptr_t end_va,
182 unsigned char* start, uintptr_t length,
183 void* (*event_callback)(void*, const char*, void*),
184 void* event_stream,
185 int (*printf_callback)(void*, const char*, ...),
186 void* printf_stream,
187 const char* options,
188 int newline);
189
190 /* container for call back state when decoding instructions */
191 typedef struct {
192 JNIEnv* env;
193 jobject dis;
194 jobject visitor;
195 jmethodID handle_event;
196 jmethodID raw_print;
197 char buffer[4096];
198 } decode_env;
199
200
201 /* event callback binding to Disassembler.handleEvent */
202 static void* event_to_env(void* env_pv, const char* event, void* arg) {
203 jlong result = 0;
204 decode_env* denv = (decode_env*)env_pv;
205 JNIEnv* env = denv->env;
206 jstring event_string = (*env)->NewStringUTF(env, event);
207 if ((*env)->ExceptionOccurred(env)) {
208 return NULL;
209 }
210
211 result = (*env)->CallLongMethod(env, denv->dis, denv->handle_event, denv->visitor,
212 event_string, (jlong) (uintptr_t)arg);
213 if ((*env)->ExceptionOccurred(env)) {
214 /* ignore exceptions for now */
215 (*env)->ExceptionClear(env);
216 return NULL;
217 }
218
219 return (void*)(uintptr_t)result;
220 }
221
222 /* printing callback binding to Disassembler.rawPrint */
223 static int printf_to_env(void* env_pv, const char* format, ...) {
224 jstring output;
225 va_list ap;
226 int cnt;
227 decode_env* denv = (decode_env*)env_pv;
228 JNIEnv* env = denv->env;
229 size_t flen = strlen(format);
230 const char* raw = NULL;
231
232 if (flen == 0) return 0;
233 if (flen < 2 ||
234 strchr(format, '%') == NULL) {
235 raw = format;
236 } else if (format[0] == '%' && format[1] == '%' &&
237 strchr(format+2, '%') == NULL) {
238 // happens a lot on machines with names like %foo
239 flen--;
240 raw = format+1;
241 }
242 if (raw != NULL) {
243 jstring output = (*env)->NewStringUTF(env, raw);
244 if (!(*env)->ExceptionOccurred(env)) {
245 /* make sure that UTF allocation doesn't cause OOM */
246 (*env)->CallVoidMethod(env, denv->dis, denv->raw_print, denv->visitor, output);
247 }
248 if ((*env)->ExceptionOccurred(env)) {
249 /* ignore exceptions for now */
250 (*env)->ExceptionClear(env);
251 }
252 return (int) flen;
253 }
254 va_start(ap, format);
255 cnt = vsnprintf(denv->buffer, sizeof(denv->buffer), format, ap);
256 va_end(ap);
257
258 output = (*env)->NewStringUTF(env, denv->buffer);
259 if (!(*env)->ExceptionOccurred(env)) {
260 /* make sure that UTF allocation doesn't cause OOM */
261 (*env)->CallVoidMethod(env, denv->dis, denv->raw_print, denv->visitor, output);
262 }
263
264 if ((*env)->ExceptionOccurred(env)) {
265 /* ignore exceptions for now */
266 (*env)->ExceptionClear(env);
267 }
268
269 return cnt;
270 }
271
272 /*
273 * Class: sun_jvm_hotspot_asm_Disassembler
274 * Method: decode
275 * Signature: (Lsun/jvm/hotspot/asm/InstructionVisitor;J[BLjava/lang/String;J)V
276 */
277 JNIEXPORT void JNICALL Java_sun_jvm_hotspot_asm_Disassembler_decode(JNIEnv * env,
278 jobject dis,
279 jobject visitor,
280 jlong startPc,
281 jbyteArray code,
282 jstring options_s,
283 jlong decode_instructions_virtual) {
284 jbyte *start = NULL;
285 jbyte *end = NULL;
286 jclass disclass = NULL;
287 const char *options = NULL;
288 decode_env denv;
289
290 start = (*env)->GetByteArrayElements(env, code, NULL);
291 if ((*env)->ExceptionOccurred(env)) {
292 return;
293 }
294 end = start + (*env)->GetArrayLength(env, code);
295 options = (*env)->GetStringUTFChars(env, options_s, NULL);
296 if ((*env)->ExceptionOccurred(env)) {
297 (*env)->ReleaseByteArrayElements(env, code, start, JNI_ABORT);
298 return;
299 }
300 disclass = (*env)->GetObjectClass(env, dis);
301
302 denv.env = env;
303 denv.dis = dis;
304 denv.visitor = visitor;
305
306 /* find Disassembler.handleEvent callback */
307 denv.handle_event = (*env)->GetMethodID(env, disclass, "handleEvent",
308 "(Lsun/jvm/hotspot/asm/InstructionVisitor;Ljava/lang/String;J)J");
309 if ((*env)->ExceptionOccurred(env)) {
310 (*env)->ReleaseByteArrayElements(env, code, start, JNI_ABORT);
311 (*env)->ReleaseStringUTFChars(env, options_s, options);
312 return;
313 }
314
315 /* find Disassembler.rawPrint callback */
316 denv.raw_print = (*env)->GetMethodID(env, disclass, "rawPrint",
317 "(Lsun/jvm/hotspot/asm/InstructionVisitor;Ljava/lang/String;)V");
318 if ((*env)->ExceptionOccurred(env)) {
319 (*env)->ReleaseByteArrayElements(env, code, start, JNI_ABORT);
320 (*env)->ReleaseStringUTFChars(env, options_s, options);
321 return;
322 }
323
324 /* decode the buffer */
325 (*(decode_func)(uintptr_t)decode_instructions_virtual)((uintptr_t) startPc,
326 startPc + end - start,
327 (unsigned char*)start,
328 end - start,
329 &event_to_env, (void*) &denv,
330 &printf_to_env, (void*) &denv,
331 options, 0 /* newline */);
332
333 /* cleanup */
334 (*env)->ReleaseByteArrayElements(env, code, start, JNI_ABORT);
335 (*env)->ReleaseStringUTFChars(env, options_s, options);
336 }