1 /*
2 * Copyright (c) 2015, 2025, Oracle and/or its affiliates. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * - Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * - Neither the name of Oracle nor the names of its
16 * contributors may be used to endorse or promote products derived
17 * from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
20 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
21 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
26 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
27 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
28 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
29 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <string.h>
33
34 #include "jimage.hpp"
35
36 #include "imageFile.hpp"
37
38 #include "jni_util.h"
39
40 /*
41 * Declare jimage library specific JNI_Onload entry for static build.
42 */
43 extern "C" {
44 DEF_STATIC_JNI_OnLoad
45 }
46
47 /*
48 * JImageOpen - Given the supplied full path file name, open an image file. This
49 * function will also initialize tables and retrieve meta-data necessary to
50 * satisfy other functions in the API. If the image file has been previously
51 * open, a new open request will share memory and resources used by the previous
52 * open. A call to JImageOpen should be balanced by a call to JImageClose, to
53 * release memory and resources used. If the image file is not found or cannot
54 * be open, then NULL is returned and error will contain a reason for the
55 * failure; a positive value for a system error number, negative for a jimage
56 * specific error (see JImage Error Codes.)
57 *
58 * Ex.
59 * jint error;
60 * JImageFile* jimage = (*JImageOpen)(JAVA_HOME "lib/modules", &error);
61 * if (image == NULL) {
62 * tty->print_cr("JImage failed to open: %d", error);
63 * ...
64 * }
65 * ...
66 */
67 extern "C" JNIEXPORT JImageFile*
68 JIMAGE_Open(const char *name, jint* error) {
69 // TODO - return a meaningful error code
70 *error = 0;
71 ImageFileReader* jfile = ImageFileReader::open(name);
72 return (JImageFile*) jfile;
73 }
74
75 /*
76 * JImageClose - Given the supplied open image file (see JImageOpen), release
77 * memory and resources used by the open file and close the file. If the image
78 * file is shared by other uses, release and close is deferred until the last use
79 * is also closed.
80 *
81 * Ex.
82 * (*JImageClose)(image);
83 */
84 extern "C" JNIEXPORT void
85 JIMAGE_Close(JImageFile* image) {
86 ImageFileReader::close((ImageFileReader*) image);
87 }
88
89 /*
90 * JImageFindResource - Given an open image file (see JImageOpen), a module
91 * name, a version string and the name of a class/resource, return location
92 * information describing the resource and its size. If no resource is found, the
93 * function returns JIMAGE_NOT_FOUND and the value of size is undefined.
94 * The version number should be "9.0" and is not used in locating the resource.
95 * The resulting location does/should not have to be released.
96 * All strings are utf-8, zero byte terminated.
97 *
98 * Ex.
99 * jlong size;
100 * JImageLocationRef location = (*JImageFindResource)(image,
101 * "java.base", "9.0", "java/lang/String.class", &size);
102 */
103 extern "C" JNIEXPORT JImageLocationRef
104 JIMAGE_FindResource(JImageFile* image,
105 const char* module_name, const char* version, const char* name,
106 jlong* size) {
107 // Concatenate to get full path
108 char fullpath[IMAGE_MAX_PATH];
109 size_t moduleNameLen = strlen(module_name);
110 size_t nameLen = strlen(name);
111 size_t index;
112
113 // TBD: assert(moduleNameLen > 0 && "module name must be non-empty");
114 assert(nameLen > 0 && "name must non-empty");
115
116 // If the concatenated string is too long for the buffer, return not found
117 if (1 + moduleNameLen + 1 + nameLen + 1 > IMAGE_MAX_PATH) {
118 return 0L;
119 }
120
121 index = 0;
122 fullpath[index++] = '/';
123 memcpy(&fullpath[index], module_name, moduleNameLen);
124 index += moduleNameLen;
125 fullpath[index++] = '/';
126 memcpy(&fullpath[index], name, nameLen);
127 index += nameLen;
128 fullpath[index++] = '\0';
129
130 JImageLocationRef loc =
131 (JImageLocationRef) ((ImageFileReader*) image)->find_location_index(fullpath, (u8*) size);
132 return loc;
133 }
134
135 /*
136 * JImageGetResource - Given an open image file (see JImageOpen), a resource's
137 * location information (see JImageFindResource), a buffer of appropriate
138 * size and the size, retrieve the bytes associated with the
139 * resource. If the size is less than the resource size then the read is truncated.
140 * If the size is greater than the resource size then the remainder of the buffer
141 * is zero filled. The function will return the actual size of the resource.
142 *
143 * Ex.
144 * jlong size;
145 * JImageLocationRef location = (*JImageFindResource)(image,
146 * "java.base", "9.0", "java/lang/String.class", &size);
147 * char* buffer = new char[size];
148 * (*JImageGetResource)(image, location, buffer, size);
149 */
150 extern "C" JNIEXPORT jlong
151 JIMAGE_GetResource(JImageFile* image, JImageLocationRef location,
152 char* buffer, jlong size) {
153 ((ImageFileReader*) image)->get_resource((u4) location, (u1*) buffer);
154 return size;
155 }
156
157 /*
158 * JImageResourceIterator - Given an open image file (see JImageOpen), a visitor
159 * function and a visitor argument, iterator through each of the image's resources.
160 * The visitor function is called with the image file, the module name, the
161 * package name, the base name, the extension and the visitor argument. The return
162 * value of the visitor function should be true, unless an early iteration exit is
163 * required. All strings are utf-8, zero byte terminated.file.
164 *
165 * Ex.
166 * bool ctw_visitor(JImageFile* jimage, const char* module_name, const char* version,
167 * const char* package, const char* name, const char* extension, void* arg) {
168 * if (strcmp(extension, "class") == 0) {
169 * char path[JIMAGE_MAX_PATH];
170 * Thread* THREAD = Thread::current();
171 * jio_snprintf(path, JIMAGE_MAX_PATH - 1, "/%s/%s", package, name);
172 * ClassLoader::compile_the_world_in(path, (Handle)arg, THREAD);
173 * return !HAS_PENDING_EXCEPTION;
174 * }
175 * return true;
176 * }
177 * (*JImageResourceIterator)(image, ctw_visitor, loader);
178 */
179 extern "C" JNIEXPORT void
180 JIMAGE_ResourceIterator(JImageFile* image,
181 JImageResourceVisitor_t visitor, void* arg) {
182 ImageFileReader* imageFile = (ImageFileReader*) image;
183 u4 nEntries = imageFile->table_length();
184 const ImageStrings strings = imageFile->get_strings();
185 for (u4 i = 0; i < nEntries; i++) {
186 ImageLocation location(imageFile->get_location_data(i));
187
188 u4 moduleOffset = (u4) location.get_attribute(ImageLocation::ATTRIBUTE_MODULE);
189 if (moduleOffset == 0) {
190 continue; // skip non-modules
191 }
192 const char *module = strings.get(moduleOffset);
193 if (strcmp(module, "modules") == 0
194 || strcmp(module, "packages") == 0) {
195 continue; // always skip
196 }
197
198 u4 parentOffset = (u4) location.get_attribute(ImageLocation::ATTRIBUTE_PARENT);
199 const char *parent = strings.get(parentOffset);
200 u4 baseOffset = (u4) location.get_attribute(ImageLocation::ATTRIBUTE_BASE);
201 const char *base = strings.get(baseOffset);
202 u4 extOffset = (u4) location.get_attribute(ImageLocation::ATTRIBUTE_EXTENSION);
203 const char *extension = strings.get(extOffset);
204
205 if (!(*visitor)(image, module, "9", parent, base, extension, arg)) {
206 break;
207 }
208 }
209 }