1/*
2 * Copyright (c) 2015, 2016, 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/*
39 * JImageOpen - Given the supplied full path file name, open an image file. This
40 * function will also initialize tables and retrieve meta-data necessary to
41 * satisfy other functions in the API. If the image file has been previously
42 * open, a new open request will share memory and resources used by the previous
43 * open. A call to JImageOpen should be balanced by a call to JImageClose, to
44 * release memory and resources used. If the image file is not found or cannot
45 * be open, then NULL is returned and error will contain a reason for the
46 * failure; a positive value for a system error number, negative for a jimage
47 * specific error (see JImage Error Codes.)
48 *
49 *  Ex.
50 *   jint error;
51 *   JImageFile* jimage = (*JImageOpen)(JAVA_HOME "lib/modules", &error);
52 *   if (image == NULL) {
53 *     tty->print_cr("JImage failed to open: %d", error);
54 *     ...
55 *   }
56 *   ...
57 */
58extern "C" JImageFile* JIMAGE_Open(const char *name, jint* error) {
59    // TODO - return a meaningful error code
60    *error = 0;
61    ImageFileReader* jfile = ImageFileReader::open(name);
62    return (JImageFile*) jfile;
63}
64
65/*
66 * JImageClose - Given the supplied open image file (see JImageOpen), release
67 * memory and resources used by the open file and close the file. If the image
68 * file is shared by other uses, release and close is deferred until the last use
69 * is also closed.
70 *
71 * Ex.
72 *  (*JImageClose)(image);
73 */
74extern "C" void JIMAGE_Close(JImageFile* image) {
75    ImageFileReader::close((ImageFileReader*) image);
76}
77
78/*
79 * JImagePackageToModule - Given an open image file (see JImageOpen) and the name
80 * of a package, return the name of module where the package resides. If the
81 * package does not exist in the image file, the function returns NULL.
82 * The resulting string does/should not have to be released. All strings are
83 * utf-8, zero byte terminated.
84 *
85 * Ex.
86 *  const char* package = (*JImagePackageToModule)(image, "java/lang");
87 *  tty->print_cr(package);
88 *  -> java.base
89 */
90extern "C" const char* JIMAGE_PackageToModule(JImageFile* image, const char* package_name) {
91    return ((ImageFileReader*) image)->get_image_module_data()->package_to_module(package_name);
92}
93
94/*
95 * JImageFindResource - Given an open image file (see JImageOpen), a module
96 * name, a version string and the name of a class/resource, return location
97 * information describing the resource and its size. If no resource is found, the
98 * function returns JIMAGE_NOT_FOUND and the value of size is undefined.
99 * The version number should be "9.0" and is not used in locating the resource.
100 * The resulting location does/should not have to be released.
101 * All strings are utf-8, zero byte terminated.
102 *
103 *  Ex.
104 *   jlong size;
105 *   JImageLocationRef location = (*JImageFindResource)(image,
106 *                                 "java.base", "9.0", "java/lang/String.class", &size);
107 */
108extern "C" JImageLocationRef JIMAGE_FindResource(JImageFile* image,
109        const char* module_name, const char* version, const char* name,
110        jlong* size) {
111    // Concatenate to get full path
112    char fullpath[IMAGE_MAX_PATH];
113    size_t moduleNameLen = strlen(module_name);
114    size_t nameLen = strlen(name);
115    size_t index;
116
117    // TBD:   assert(moduleNameLen > 0 && "module name must be non-empty");
118    assert(nameLen > 0 && "name must non-empty");
119
120    // If the concatenated string is too long for the buffer, return not found
121    if (1 + moduleNameLen + 1 + nameLen + 1 > IMAGE_MAX_PATH) {
122        return 0L;
123    }
124
125    index = 0;
126    fullpath[index++] = '/';
127    memcpy(&fullpath[index], module_name, moduleNameLen);
128    index += moduleNameLen;
129    fullpath[index++] = '/';
130    memcpy(&fullpath[index], name, nameLen);
131    index += nameLen;
132    fullpath[index++] = '\0';
133
134    JImageLocationRef loc =
135            (JImageLocationRef) ((ImageFileReader*) image)->find_location_index(fullpath, (u8*) size);
136    return loc;
137}
138
139/*
140 * JImageGetResource - Given an open image file (see JImageOpen), a resource's
141 * location information (see JImageFindResource), a buffer of appropriate
142 * size and the size, retrieve the bytes associated with the
143 * resource. If the size is less than the resource size then the read is truncated.
144 * If the size is greater than the resource size then the remainder of the buffer
145 * is zero filled.  The function will return the actual size of the resource.
146 *
147 * Ex.
148 *  jlong size;
149 *   JImageLocationRef location = (*JImageFindResource)(image,
150 *                                 "java.base", "9.0", "java/lang/String.class", &size);
151 *  char* buffer = new char[size];
152 *  (*JImageGetResource)(image, location, buffer, size);
153 */
154extern "C" jlong JIMAGE_GetResource(JImageFile* image, JImageLocationRef location,
155        char* buffer, jlong size) {
156    ((ImageFileReader*) image)->get_resource((u4) location, (u1*) buffer);
157    return size;
158}
159
160/*
161 * JImageResourceIterator - Given an open image file (see JImageOpen), a visitor
162 * function and a visitor argument, iterator through each of the image's resources.
163 * The visitor function is called with the image file, the module name, the
164 * package name, the base name, the extension and the visitor argument. The return
165 * value of the visitor function should be true, unless an early iteration exit is
166 * required. All strings are utf-8, zero byte terminated.file.
167 *
168 * Ex.
169 *   bool ctw_visitor(JImageFile* jimage, const char* module_name, const char* version,
170 *                  const char* package, const char* name, const char* extension, void* arg) {
171 *     if (strcmp(extension, "class") == 0) {
172 *       char path[JIMAGE_MAX_PATH];
173 *       Thread* THREAD = Thread::current();
174 *       jio_snprintf(path, JIMAGE_MAX_PATH - 1, "/%s/%s", package, name);
175 *       ClassLoader::compile_the_world_in(path, (Handle)arg, THREAD);
176 *       return !HAS_PENDING_EXCEPTION;
177 *     }
178 *     return true;
179 *   }
180 *   (*JImageResourceIterator)(image, ctw_visitor, loader);
181 */
182extern "C" void JIMAGE_ResourceIterator(JImageFile* image,
183        JImageResourceVisitor_t visitor, void* arg) {
184    ImageFileReader* imageFile = (ImageFileReader*) image;
185    u4 nEntries = imageFile->table_length();
186    const ImageStrings strings = imageFile->get_strings();
187    for (u4 i = 0; i < nEntries; i++) {
188        ImageLocation location(imageFile->get_location_data(i));
189
190        u4 moduleOffset = (u4) location.get_attribute(ImageLocation::ATTRIBUTE_MODULE);
191        if (moduleOffset == 0) {
192            continue; // skip non-modules
193        }
194        const char *module = strings.get(moduleOffset);
195        if (strcmp(module, "modules") == 0
196            || strcmp(module, "packages") == 0) {
197            continue; // always skip
198        }
199
200        u4 parentOffset = (u4) location.get_attribute(ImageLocation::ATTRIBUTE_PARENT);
201        const char *parent = strings.get(parentOffset);
202        u4 baseOffset = (u4) location.get_attribute(ImageLocation::ATTRIBUTE_BASE);
203        const char *base = strings.get(baseOffset);
204        u4 extOffset = (u4) location.get_attribute(ImageLocation::ATTRIBUTE_EXTENSION);
205        const char *extension = strings.get(extOffset);
206
207        if (!(*visitor)(image, module, "9", parent, base, extension, arg)) {
208            break;
209        }
210    }
211}
212
213/*
214 * JIMAGE_ResourcePath- Given an open image file, a location reference, a buffer
215 * and a maximum buffer size, copy the path of the resource into the buffer.
216 * Returns false if not a valid location reference.
217 *
218 * Ex.
219 *   JImageLocationRef location = ...
220 *   char path[JIMAGE_MAX_PATH];
221 *    (*JImageResourcePath)(image, location, path, JIMAGE_MAX_PATH);
222 */
223extern "C" bool JIMAGE_ResourcePath(JImageFile* image, JImageLocationRef locationRef,
224                                    char* path, size_t max) {
225    ImageFileReader* imageFile = (ImageFileReader*) image;
226
227    u4 offset = (u4) locationRef;
228    if (offset >= imageFile->locations_size()) {
229        return false;
230    }
231
232    ImageLocation location(imageFile->get_location_offset_data(offset));
233    imageFile->location_path(location, path, max);
234
235    return true;
236}
237