1 // Copyright 2001,2007 Alan Donovan. All rights reserved. 2 // 3 // Author: Alan Donovan <adonovan (at) google.com> 4 // 5 // Licensed under the Apache License, Version 2.0 (the "License"); 6 // you may not use this file except in compliance with the License. 7 // You may obtain a copy of the License at 8 // 9 // http://www.apache.org/licenses/LICENSE-2.0 10 // 11 // Unless required by applicable law or agreed to in writing, software 12 // distributed under the License is distributed on an "AS IS" BASIS, 13 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 // See the License for the specific language governing permissions and 15 // limitations under the License. 16 // 17 // ijar.cpp -- .jar -> _interface.jar tool. 18 // 19 20 #include <stdio.h> 21 #include <string.h> 22 #include <stdlib.h> 23 #include <limits.h> 24 #include <errno.h> 25 #include <memory> 26 27 #include "zip.h" 28 29 namespace devtools_ijar { 30 31 bool verbose = false; 32 33 // Reads a JVM class from classdata_in (of the specified length), and 34 // writes out a simplified class to classdata_out, advancing the 35 // pointer. 36 void StripClass(u1 *&classdata_out, const u1 *classdata_in, size_t in_length); 37 38 const char* CLASS_EXTENSION = ".class"; 39 const size_t CLASS_EXTENSION_LENGTH = strlen(CLASS_EXTENSION); 40 41 // ZipExtractorProcessor that select only .class file and use 42 // StripClass to generate an interface class, storing as a new file 43 // in the specified ZipBuilder. 44 class JarStripperProcessor : public ZipExtractorProcessor { 45 public: 46 JarStripperProcessor() {} 47 virtual ~JarStripperProcessor() {} 48 49 virtual void Process(const char* filename, const u4 attr, 50 const u1* data, const size_t size); 51 virtual bool Accept(const char* filename, const u4 attr); 52 53 private: 54 // Not owned by JarStripperProcessor, see SetZipBuilder(). 55 ZipBuilder* builder; 56 57 public: 58 // Set the ZipBuilder to add the ijar class to the output zip file. 59 // This pointer should not be deleted while this class is still in use and 60 // it should be set before any call to the Process() method. 61 void SetZipBuilder(ZipBuilder* builder) { 62 this->builder = builder; 63 } 64 }; 65 66 bool JarStripperProcessor::Accept(const char* filename, const u4) { 67 ssize_t offset = strlen(filename) - CLASS_EXTENSION_LENGTH; 68 if (offset >= 0) { 69 return strcmp(filename + offset, CLASS_EXTENSION) == 0; 70 } 71 return false; 72 } 73 74 void JarStripperProcessor::Process(const char* filename, const u4, 75 const u1* data, const size_t size) { 76 if (verbose) { 77 fprintf(stderr, "INFO: StripClass: %s\n", filename); 78 } 79 u1 *q = builder->NewFile(filename, 0); 80 u1 *classdata_out = q; 81 StripClass(q, data, size); // actually process it 82 size_t out_length = q - classdata_out; 83 builder->FinishFile(out_length); 84 } 85 86 // Opens "file_in" (a .jar file) for reading, and writes an interface 87 // .jar to "file_out". 88 void OpenFilesAndProcessJar(const char *file_out, const char *file_in) { 89 JarStripperProcessor processor; 90 std::unique_ptr<ZipExtractor> in(ZipExtractor::Create(file_in, &processor)); 91 if (in.get() == NULL) { 92 fprintf(stderr, "Unable to open Zip file %s: %s\n", file_in, 93 strerror(errno)); 94 abort(); 95 } 96 u8 output_length = in->CalculateOutputLength(); 97 std::unique_ptr<ZipBuilder> out(ZipBuilder::Create(file_out, output_length)); 98 if (out.get() == NULL) { 99 fprintf(stderr, "Unable to open output file %s: %s\n", file_out, 100 strerror(errno)); 101 abort(); 102 } 103 processor.SetZipBuilder(out.get()); 104 105 // Process all files in the zip 106 if (in->ProcessAll() < 0) { 107 fprintf(stderr, "%s\n", in->GetError()); 108 abort(); 109 } 110 111 // Add dummy file, since javac doesn't like truly empty jars. 112 if (out->GetNumberFiles() == 0) { 113 out->WriteEmptyFile("dummy"); 114 } 115 // Finish writing the output file 116 if (out->Finish() < 0) { 117 fprintf(stderr, "%s\n", out->GetError()); 118 abort(); 119 } 120 // Get all file size 121 size_t in_length = in->GetSize(); 122 size_t out_length = out->GetSize(); 123 if (verbose) { 124 fprintf(stderr, "INFO: produced interface jar: %s -> %s (%d%%).\n", 125 file_in, file_out, 126 static_cast<int>(100.0 * out_length / in_length)); 127 } 128 } 129 130 } // namespace devtools_ijar 131 132 // 133 // main method 134 // 135 static void usage() { 136 fprintf(stderr, "Usage: ijar [-v] x.jar [x_interface.jar>]\n"); 137 fprintf(stderr, "Creates an interface jar from the specified jar file.\n"); 138 exit(1); 139 } 140 141 int main(int argc, char **argv) { 142 const char *filename_in = NULL; 143 const char *filename_out = NULL; 144 145 for (int ii = 1; ii < argc; ++ii) { 146 if (strcmp(argv[ii], "-v") == 0) { 147 devtools_ijar::verbose = true; 148 } else if (filename_in == NULL) { 149 filename_in = argv[ii]; 150 } else if (filename_out == NULL) { 151 filename_out = argv[ii]; 152 } else { 153 usage(); 154 } 155 } 156 157 if (filename_in == NULL) { 158 usage(); 159 } 160 161 // Guess output filename from input: 162 char filename_out_buf[PATH_MAX]; 163 if (filename_out == NULL) { 164 size_t len = strlen(filename_in); 165 if (len > 4 && strncmp(filename_in + len - 4, ".jar", 4) == 0) { 166 strcpy(filename_out_buf, filename_in); 167 strcpy(filename_out_buf + len - 4, "-interface.jar"); 168 filename_out = filename_out_buf; 169 } else { 170 fprintf(stderr, "Can't determine output filename since input filename " 171 "doesn't end with '.jar'.\n"); 172 return 1; 173 } 174 } 175 176 if (devtools_ijar::verbose) { 177 fprintf(stderr, "INFO: writing to '%s'.\n", filename_out); 178 } 179 180 devtools_ijar::OpenFilesAndProcessJar(filename_out, filename_in); 181 return 0; 182 } 183
