JCGO - Java source to C code translator                  ---------------------------------------                         version 1.16 (2014-04-29)                         -------------------------                               User's Guide                               ------------Copyright (C) 2001-2014 Ivan Maidanski <ivmai@mail.ru>Copyright 2010 IvMaiSoft LLC.http://www.ivmaisoft.comAll rights reserved.Disclaimer----------Use of this software is subject to license terms.This is free software distributed under the GPL license with the GNUClasspath exception. See LICENSE file for more details.Preface-------JCGO (pronounced as "j-c-go") is a software application which translates(converts) programs written in Java into platform-independent C code,which could, further, be compiled (by third-party tools) intohighly-optimized native code for the target platform and deployed.JCGO application is a powerful solution that enables your desktop,server-side and embedded/mobile/wireless Java applications to take fulladvantage of the underlying hardware. In addition, JCGO effectivelyprotects your intellectual property by making your programs whencompiled to native code as hard to reverse engineer as if they werewritten in C/C++.JCGO consists of the following parts: the translator executables (onefor every supported development platform), the JCGO-specific partof the Java runtime environment, the JCGO-specific part of a C runtimeenvironment, the precompiled libraries part, the supplementary andJCGO-specific auxiliary tools, miscellaneous and sample source files,and the accompanying documentation.Licensing, warranty and trademarks issues-----------------------------------------This software and its documentation have been tested and reviewed.Nevertheless, the author makes no warranty or representation, eitherexpress or implied, with respect to the software and documentationincluded with this application. In no event will the author be liable fordirect, indirect, special, incidental or consequential damagesresulting from any defect in the software or documentation includedwith this application.Java (tm) and all Java-based trademarks and logos are trademarksor registered trademarks of Sun Microsystems, Inc.All trademarks and copyrights mentioned in this documentation are theproperty of their respective holders.The rest of the JCGO is covered by GNU General Public License (GPL),version 2, with a special exception (so called "GNU Classpath exception"),which gives you the right to use it within any other software regardless ofthe license terms (see exact license information in the header of an opensource file).JCGO may contain a number of third-party open-source materials.Please read COPYING file carefully for the fulllicensing information. For any included third-party sources see thelicense information in the header of that files. For any includedlibraries in a binary form see licenses supplied in their sources andwith the corresponding C compilers.Official project web site-------------------------The JCGO project official web home page is:http://www.ivmaisoft.com/jcgo/The JCGO development repository web page is:https://github.com/ivmai/JCGOIntroduction------------Thank you for downloading JCGO application - the tool for creationof conventional native code applications using the Java programminglanguage. JCGO takes Java source files as input and translates theminto a set of files in the platform-independent C programming language,which is further compiled to a binary executable for your targetplatform by a standard ANSI C/C++ compiler.JCGO translator uses some optimization algorithms that allow, togetherwith optimizations performed by a C compiler, the resulting executablecode to reach better performance if compared with the traditional Javaimplementations (based on the Just-In-Time technology).The produced executable does not contain nor require a Java VirtualMachine to execute, so its resource requirements are smaller than thatrequired by a typical Java VM. This also simplifies the processof deployment and distribution of an application. In addition, theproduced native code is highly resistant to reverse engineering andtampering.JCGO at a glance----------------Producing a native executable file for your Java application is donein three steps with the JCGO application: generation of C codefiles from Java source files, compiling these C code files into one ormore machine-dependent object files, and linking them all together withC library into a binary executable file.The JCGO translator (which is, in other words, a "retargetable"optimizing Java-source-to-C static whole-program compiler) transformsthe Java source files of your application, the source files of all Javalibraries used by your application, the source files of the standardclass library (the Java Runtime Environment) and a number of theJCGO-specific Java files together (constituting the "translation set"of Java files) at once into a set of files with optimized (buthuman-readable) platform-independent ISO/ANSI C code. Thistransformation is performed on the developer's system, which may differfrom the target system of your application. If you need to pack anyresource files (only the standard Java property file) into yourapplication then you should convert these resource files into thecorresponding Java source files (a special stand-alone utilityis supplied within the JCGO application to automate thisconversion) beforehand and pass them too as an input to the JCGOtranslator.To create a native executable file for your application (processed withthe JCGO translator) you need a standard ISO/ANSI C compiler and linkerfor the target platform (the target hardware and operating system).Since JCGO generates platform-independent C code and uses only a smallcross-platform (portable) set of the standard C library functions,there is a large number of platforms supported - based on different CPUarchitectures (e.g., x86, amd64, ppc, ppc64, ia64, sparc, alpha, mips,i8086, arm, sh, xscale, etc.) and running different Operating Systems(e.g., Windows, FreeBSD, GNU/Linux, Mac OS X (Darwin), Solaris SunOS,OS/2, pure DOS, BeOS, PocketPC/WinMobile/WinCE, or even without OS,etc.).By using the desired C compiler toolkit, you compile the generatedC code files (all at once as a single compilation unit or each fileseparately) for your Java application together with the JCGO-specificC part of Java runtime. A lot of C macros are provided to customize thecompilation process and the resulting executable. Besides, a typicalC compiler offers a good set of options to control code optimizationand debugging support features.The linkage step for your application is done by the desired C compilertoolkit in the same way as for a normal C program except thata precompiled Garbage Collector library (either static or dynamic)is linked with it too.Java compliance and unsupported features----------------------------------------JCGO is compliant with the Java 2 Standard Edition (J2SE) v1.4platform. JCGO uses GNU Classpath v0.93 core class library.JCGO does not support Java exception stack tracing. JCGO does notsupport the features introduced in the 3rd version of the Java LanguageSpecification and J2SE v1.5 platform.JCGO optimization techniques----------------------------JCGO translator itself performs at least the following local and globaloptimizations:- unused class, methods and fields elimination;- marking suitable methods for inlining;- turning virtual calls into direct ones;- turning all interface method calls into either virtual or directones;- fields, local variables and parameters reordering;- runtime checks for null pointer, array index, cast type elimination;- on-the-stack object allocation;- performing class initialization at program start-up;- removing unused class meta-information for "Reflection" API;- packing characters of Latin-1 strings into byte arrays;- putting static arrays into program image data sections;- putting strings, classes and immutable arrays into program imageread-only section.The further optimizations of the code are done by the C compiler youuse.JCGO advantages and drawbacks-----------------------------JCGO employs the concept of the Ahead-of-Time (static) compilationon the developer's system which gives at least the following advantagesover the traditional Java VM runtime interpretation and Just-in-Time(JIT) compilation to the compiled programs:- faster execution and smaller memory footprint (no codeinterpretation, no unused class meta-information, large set of localand global optimization, runtime checks elimination, code and read-onlydata sharing across multiple running program instances);- shorter start-up time (no class load, no class verification, no JIT,functions and static data reordering for faster executable on-demandloading);- more performance tuning flexibility (you may choose less program sizeor more speed, more robustness or more speed);- native and easier program deployment (a single native executable,no stand-alone Java VM Runtime Environment needed, has own name in theprocess list, applicability of native code packers, code protectors andcustom installer creators);- better resistance to code decompilation and reverse engineering (thecompiled program is as hard to decompile as for a conventional C/C++program).These advantages identify, in fact, the goals that may be achievedby applying the JCGO to your application.The drawbacks of JCGO in respect to the Ahead-of-Time compilation are:- not cross-platform (native executable is created only for the targetsystem specified at compilation time);- no runtime-specific optimizations and profiling (all optimizationsare done at the developer's host and for the specified CPU model only);- no support for dynamic applications (all the classes comprising theapplication must be passed to JCGO and compiled to native code at thedeveloper's host, all functions and fields accessed through the Java"Reflection" API should be generally identified).JCGO translates Java source files instead of binary Java class filesof your application - this gives the following advantages:- some more optimizations are possible;- the produced C code is more human-readable;- no need to have a "javac" tool and to manually compile Java sourcefiles to Java class binary files.The drawback of this approach is:- full sources of the application and the used libraries are needed(you have to decompile Java class binary files if the required Javasource files are missing and, of course, if this is legal by theapplicable license).JCGO translates the sources of an application all at once and aC compiler processes the generated C files all at once. The advantagesof "all-at-once" translation and compilation are:- more global optimizations are possible;- only needed part of the Java VM runtime is compiled;- unused classes, methods, fields are all eliminated;- more methods are possible to inline.The drawbacks of the "all-at-once" approach are:- everything should be re-translated to C and recompiled if any Javasource is changed;- code duplication in every application executable file is present (forthe Java runtime code and used libraries);- the JCGO translator and a C compiler use a lot of system resources(CPU and RAM) to do the work.JCGO translates your Java application to a native executable in 3 steps(to C code first, then to object file, and then to executable file).The "through C" conversion model gives you the following advantagesover the direct Java-to-executable conversion model:- much more portability (JCGO has a wide range of the supported targetsystems);- allows you to treat Java application as a normal C one (this meansthat you have much more control over optimization and code tuning, youhave ability to look through, verify, adopt the code in C, have abilityto use verified and time-proven C/C++ compilers, and you have thepossibility to debug and profile your application with the standardC tools);- gives you flexibility in linking an application with the GarbageCollector and other third-party libraries (both static and dynamicmethods of linking are supported).The drawbacks of the "through C" approach are:- you need a C compiler for the target system to succeed;- the used C compiler (and/or linker) may contain bugs;- it is harder for you to compile an application (you should known theC programming language and have skills in C compilation and linking,you have to manually invoke the C compiler).Note, however, that while JCGO produces human-readable C code, thiscode does not contain comments and is not maintainable (i.e., youcannot really use JCGO for your project to migrate from Java to C).Note also, as an advantage, that JCGO contains and uses only free opensources (except when an AWT GUI application is translated - Sun J2SEv1.4.2 community sources could be used in this case).Scope of possible applicability-------------------------------JCGO is targeted mainly for the following user categories:- application software developers (to get higher performance, smallermemory footprint and smaller start-up time for an application,to protect the code as an intellectual property, to allowan application to execute on platforms without the Java VM support,to simplify deployment, distribution and installation of anapplication, to apply time-proven and well-known C/C++ compilation anddebugging tools to a Java application);- hardware device developers (to migrate from C device code to Java,to write new device code in Java with nearly the same performanceefficiency as in C, to use Java for 8- and 16-bit CPUs with ROM-ablecode and small amount of RAM, to reuse existing Java code for smalldevice programming);- software porting men (to execute existing applications on platformswithout a Java VM support);- software advanced users (to get higher performance for frequentlyused applications, to run an application in the 64-bit mode).Development system requirements-------------------------------At present the JCGO translator itself is built to be executed on any"x86" platform running GNU/Linux or Windows operating system.The minimal hardware requirements for the JCGO translator are:- Intel Pentium III 500 MHz CPU (or equivalent);- 1024 MiB RAM;- 200 MiB free disk space.The amount of available real RAM space is critical - you should haveat least 200 KiB per every class included in the "translation set"in average, otherwise the performance of the JCGO translatorsignificantly degrades.Operating System requirement for the JCGO translator is (one of):- Microsoft Windows 2000 or higher (to run "jcgo.exe" on Win32);- GNU/Linux OS based on Kernel 2.6 or higher (to run Linux versionof "jcgo");- Sun JRE 1.4 or higher (to run "jcgo.jar" as an alternative to Windowsand Linux native binary versions of the JCGO translator).Other development platforms and operating systems could be supportedin the future. Note also, that the target platformof a translated application does not depend of the development platformused to run the JCGO translator.Note about running "jcgo.jar": translation of a big applicationrequires a big stack, so please pass "-Xss" option to JVM witha reasonable value.Required knowledge and skills-----------------------------To use the JCGO translator successfully you should generallybe familiar with the C programming language and have adequate skillsin the compilation area with the C compiler you choose to use for thetarget platform.It is also supposed that you know the name of the class with the entrypoint of the application you translate, the names of all the classesaccessed dynamically from the application, the fully-qualified namesof all the methods and fields accessed from the application through theJava "Reflection" API.Downloading prerequisites-------------------------To start using the JCGO application you need to download the JCGOdistributive files and install it successfully.The following files constitutes "the JCGO distributive files":- jcgo-src-1_XX.tar.bz2 (the source files used by JCGO and by aC compiler);- jcgo-lib-1_XX.tar.gz (the auto-generated Java files used by JCGO,precompiled libraries and auxiliary executables for the supportedplatforms, as well as the JCGO translator executable for a Java VM);- jcgo-bin-win32-x86.zip (the JCGO translator executable for Windowsdevelopment host, optional file);- jcgo-bin-1_XX-linux-x86.tar.gz (the JCGO translator executable forLinux/x86 development host, optional file);- classpath-0.93.tar.gz (the GNU Classpath - Essential Libraries forJava).Note: version 0.93 of the GNU Classpath is the only supported version -its later versions are incompatible with JCGO currently.In addition, in case you need a custom-specific Garbage Collector (GC)library (e.g., for a specific target platform) which is not among theprecompiled libraries, then its sources should be downloaded too and,then, compiled manually as required. At present, only two GC librariesare supported:- Boehm-Demers-Weiser Conservative GC (BDWGC, BoehmGC) version 7.2 orlater (with built-in or external libatomic_ops library);- TinyGC (Tiny Garbage Collector) - a binary-compatible smallalternative to Boehm GC (normally, should be used only for targetswhere Boehm GC is not supported or is unappropriated).To manually compile the desired GC library, please downloadgc-7.2.tar.gz (or newer) for Boehm GC, or tinygc-2_5.tar.bz2 (or newer)for TinyGC.The exact links to the distributive files (and their exact names forthe current JCGO version) are provided at the JCGO official web homepage.To compile an SWT GUI application, you will need the corresponding(i.e., for the required target platform) SWT library sources (of version3.5 or newer - please refer to reflgen/swt.dat for the exact informationof the supported versions).To compile an application which uses Sun Javax Comm API, you will needeither RXTX library sources (version 2.2) or the original Sun JavaCommunications API library sources.To compile an application that accesses OS API via JNA, you will needJNA (Java Native Access) library sources (version 3.2.7).Note also, that you need some more distributive files to translatean AWT GUI application (e.g., with Sun Win32/X11 AWT back-ends) or anAWT/SWT application which uses Java Sound API, or an SQL applicationthat uses Sun JDBC-ODBC bridge:- jcgo-sunawt-lib-1_XX.tar.gz (the JCGO-SUNAWT auto-generated Javafiles used by the JCGO translator and precompiled import libraries);- jcgo-sunawt-linux-x86-1_00.tar.gz (JCGO-SUNAWT runtime binaryre-distributive pack for GNU Linux/x86 targets);- jcgo-sunawt-solaris-x86-1_00.tar.gz (JCGO-SUNAWT runtime binaryre-distributive pack for Solaris SunOS/x86 targets);- jcgo-sunawt-win32-x86-1_00.7z (JCGO-SUNAWT runtime binaryre-distributive pack for Windows/x86 targets);- j2sdk-1_4_2-src-scsl.zip (Sun J2SDK v1.4.2 SCSL sources);- src.zip from the Sun J2SE v1.4.2_19 SDK (Sun Java core API classsources).JCGO also supports SQLite database connectivity via SqliteJDBC library.Entirely for the purpose of the distributive files unpacking, you needsome tar+gz/bz2 unpacker tool (e.g., tar and ungzip/bzip2 for Unix-likeOS, or "7-Zip" for Windows).Installation procedure----------------------Before installing the current version of the JCGO, please completelyremove the previous one installation (if you have any).Then, please extract the JCGO distributive files (using an unpackertool of your choice) into the "JCGO home" (base) installation folderpreserving the directory structure. The recommended name for the JCGOhome is "C:\JCGO" on Windows ("/usr/share/JCGO" on Unix-like system),but you are free to use any other folder (directory) for it.For AWT GUI applications translation, as a special exception (for theabove unpacking rule), j2sdk-1_4_2-src-scsl.zip should be unpackedto the newly-created "contrib/j2sdk-1_4_2-src-scsl" folder (of the "JCGO"installation folder) and src.zip from the Sun J2SE v1.4.2_19 SDK - to"contrib/j2sdk1.4.2_19/src", respectively.Note: at the end of the installation process it is better to protectthe entire JCGO installation folder and all its contents froman accidental modification (never add, delete, or modify files withinthe JCGO application - if you need to use a modified version ofa source file then copy it to your project first), so please set"read-only" access to the entire JCGO installation folder and itssubfolders (if this protection mechanism is supported by the FileSystem).JCGO home folder contents-------------------------After you complete the JCGO installation process, the JCGO home foldercontents are as follows:- "auxbin" - the JCGO auxiliary tools ("GenRefl", "JPropJav" and"TraceJni" utilities);- "classpath-0.93" - the unpacked contents of the GNU Classpath("Essential Libraries for Java") distributive file;- "contrib" - folder for 3rd-party content used by JCGO (bdwgc, tinygc,swt, j2sdk-1_4_2-src-scsl, j2sdk1.4.2_19/src, etc.);- "dlls" - precompiled dynamic-link (shared object) libraries (for thesupported platforms);- "examples" - several simple Java samples (like "Hello world")to translate;- "goclsp" - a set of JCGO-specific partial replacements and fixes forGNU Classpath;- "include" - the JCGO C core runtime (compiled together with theoutput of the JCGO translator);- "jnidload" - the source for creating JCGO-specific static trampolineswith distinctive names for multiple dynamically-loaded "JNI_OnLoad" and"JNI_OnUnload" functions (for the case when these functions areresiding in multiple dynamic libraries but used together);- "jtrsrc" - the JCGO translator source;- "libs" - precompiled libraries (for "x86" and "amd64" platforms only,might be used by a C linker);- "minihdr" - minimal subset of the standard ISO/ANSI C compiler headerfiles sufficient to compile the JCGO C core runtime and nativeback-ends (useful only for non-standard C runtime environments);- "miscsrc" - miscellaneous C and Java sources ("JAWT" stub sharedlibrary source, "JPropJav" utility source, "T-PThread" library sourceand header, "WinMain" wrapper source);- "mkjcgo" - scripts to verify JCGO Java source (using JDK), generatecontents of "rflg_out", and rebuild "auxbin", "libs", jcgo.jar/exe;- "native" - the JCGO C native back-ends (file I/O, network I/O,process execution, OS-specific properties retrieval);- "reflgen" - JNI method and field reflection usage data and thesources of the JCGO tools for handling the reflection usage data;- "rflg_out" - the addendum Java source files used by the JCGOtranslator (generated automatically by "JPropJav" utility fromgoclsp/clsp_fix/resource, classpath-0.93/resource, and by "GenRefl"utility from reflgen/*.dat files);- "COPYING" - GNU General Public License;- "LICENSE" - JCGO software license agreement;- "README" - the JCGO "read me" and documentation (this file);- "README_QUICK.txt" - the JCGO quick start tips (for Windows and Linux);- "Samples" - C compilation samples;- "jcgo" - the JCGO translator executable (for GNU/Linux on x86 host);- "jcgo.exe" - the JCGO translator executable (for Win32 host);- "jcgo.jar" - the JCGO translator executable (for Java VM);- "stdpaths.in" - response file (containing the "core" source paths)for the JCGO translator;- "sawt_out" - the precompiled (generated) parts of the additional"JCGO-SUNAWT" pack (distributed separately);- "sunawt" - the sources of the additional "JCGO-SUNAWT" pack (optional)integrating the Sun J2SE v1.4.2 AWT/JSound/SQL front-ends.JCGO translator command-line arguments--------------------------------------The JCGO translator itself ("jcgo") is a command-line tool. It acceptsthe following arguments:- optional "verbose mode" switch (-v);- optional output existing folder name switch (-d <directory>) for thegenerated ".c" and ".h" files to put in (otherwise, "jcgo_Out" folderin the current folder is created and used);- the full name of the class with "main(String[])" method of theapplication to translate;- source paths list specifier switch (-sourcepath <pathlist> or -src<pathlist> for short) for the translator to get Java source files from(notes: the order of paths is important; it is possible to use "$~"as a path prefix meaning the JCGO home (installation) folder; thecurrent folder is always implicitly added to the end of the specifiedlist; it is also possible to use "conditional" paths, in the formof <path>/$%<packageOrClass>, meaning that the specified source pathshould be used only to search for the designated class or classeswithin the designated package);- optional additional full class names (for the classes useddynamically via "Class.forName()" calls or through the Java"Reflection" API, including Proxy classes);- optional command (-r<flags> <packageOrClass>) to force particularmembers reflection for a given class or for all classes (of the"translation set") inside a given package (flags specifier:[p|[[p]c][g|[p]m][[p]f]], where flag symbol 'c' means reflect allconstructors (if with 'p' prefix then only public entities),'g' - reflect all declared public non-static getter and setter methods,['p']'m' - reflect all declared [public] methods, ['p']'f' - reflectall declared [public] fields, single 'p' flag is equivalent to "pcpmpf"specifier, and the flags omission has the same meaning as "cmf" one);- optional "response" file (@<filename>) for user conveniencecontaining optional additional full class names (one per line),optional source paths list specifier switches ("$~" prefix couldbe used here too), and optional "-r" commands.Translating first sample application------------------------------------The sample conversion of "Hello world" application on Windows andUnix-like development hosts (for the same targets) is provided bellow.It is assumed that the JCGO software is installed into its recommendedfolder. It is also assumed that "C:\MyProject" ("/home/user/MyProject"on Unix) folder exists, in which the resulting "hello.exe" ("hello"on Unix) native executable file would be put.For Windows development host and target ("MinGW" C/C++ compiler is usedhere):cd C:\MyJcgoProjectsmkdir .\HelloC:\JCGO\jcgo -d .\Hello -sourcepath $~\examples\simple Hello @$~\stdpaths.ingcc -IC:\JCGO\include -IC:\JCGO\include\boehmgc -IC:\JCGO\native -DJCGO_FFDATA -o hello .\Hello\Main.c C:\JCGO\libs\x86\mingw\libgc.aFor Linux (on x86) development host and target:cd /home/user/MyJcgoProjectsmkdir ./Hello/usr/share/JCGO/jcgo -d ./Hello -sourcepath $~/examples/simple Hello \ @$~/stdpaths.ingcc -I /usr/share/JCGO/include -I /usr/share/JCGO/include/boehmgc \ -I /usr/share/JCGO/native -fwrapv -DJCGO_UNIX -D_IEEEFP_H \ -DJCGO_UNIFSYS -o hello Hello/Main.c -lm \ /usr/share/JCGO/libs/x86/linux/libgc.aAppendix A: The core source paths for the JCGO translator---------------------------------------------------------goclsp/clsp_asc - include only to use only Latin-1/UTF-8 in streams;goclsp/clsp_fix - normally should be included (Classpath fixes);goclsp/clsp_ldr - normally should be included;goclsp/clsp_pgk - include only to use Gtk GNU AWT back-end;goclsp/clsp_pqt - include only to use Qt GNU AWT back-end;goclsp/clsp_res - must be always included;goclsp/fpvm - include only to redirect Math to StrictMath methods;goclsp/vm - must be always included (VM-specific classes);goclsp/vm_str - normally should be included (packed strings support);rflg_out - normally should be included;classpath-0.93 - must be always included ("Java essential" classes);classpath-0.93/external/relaxngDatatype - normally should be included;classpath-0.93/external/sax - normally should be included;classpath-0.93/external/w3c_dom - normally should be included.Appendix B: Environment variables recognized by the JCGO runtime----------------------------------------------------------------LOGNAME or USER, or USERNAME - "user.name" property ("anonymous"by default);USERLANG - "user.language" property ("en" by default);USERCTRY - "user.region" property ("US" by default);CODEPAGE - "file.encoding" property ("ISO8859_1" by default);CONSOLE_CODEPAGE - alternate encoding for the console output(stdout/stderr);UNICODE_ENCODING - "sun.io.unicode.encoding" property (either"UnicodeLittle" or "UnicodeBig");PROCESSOR_ARCHITECTURE or MACHTYPE, or HOSTTYPE - "os.arch" property("x86" by default);NUMBER_OF_PROCESSORS - number of available processors (1 by default);HOME or HOMEPATH, or USERPROFILE - "user.home" property;TMP or TMPDIR, or TEMP - "java.io.tmpdir" property;PROG_JAVA_HOME - explicit (non-default) "java.home" property;CLASSPATH - for "java.class.path" property;CLASSPATH_HOME - "gnu.classpath.home" property;LD_LIBRARY_PATH and PATH - for "java.library.path" property;PATHEXT - pathlist of valid non-Unix program extensions (e.g.,".EXE;.BAT");TZ=zzz[+/-]d[d][lll] - time zone information (for "user.timezone"property);JAVA_PROPS - space-separated list of custom Java properties(-Dname=value);NO_TIME_HIGH_RESOLUTION - do not use Win32 system timer resolutionswitching;STDERROUT_LOGFILE - file name for the redirected stderr/stdout (ifturned on);USE_UNICODE_API - explicitly specify whether to use Unicode system APIwhere possible (if allowed) or use its ASCII (multibyte) variant ("0"to use ASCII).Appendix C: Environment variables recognized by the Garbage Collector---------------------------------------------------------------------GC_DONT_GC - turn off garbage collection;GC_ENABLE_INCREMENTAL - turn on incremental garbage collection mode(may not work correctly on some platforms);GC_DISABLE_INCREMENTAL - disable incremental garbage collection modeexplicitly turned on by an application;GC_PRINT_STATS - turn on statistic printing on every garbagecollection;GC_ALL_INTERIOR_POINTERS - turn on "all-interior-pointers" collectormode;GC_IGNORE_GCJ_INFO - ignore the GCJ-style type descriptors (ifsupported);GC_FORCE_UNMAP_ON_GCOLLECT - force immediate memory unmapping (ifsupported) on explicitly-initiated garbage collections;GC_INITIAL_HEAP_SIZE - set initial heap size (in bytes);GC_MAXIMUM_HEAP_SIZE - set maximum heap size (in bytes);GC_FREE_SPACE_DIVISOR - change the default trade-off between garbagecollection and heap growth;GC_PAUSE_TIME_TARGET - set the desired garbage collection maximal pausetime (incremental collection time limit, in milliseconds);GC_UNMAP_THRESHOLD - change the default "threshold" value (ifsupported) for the garbage collector free blocks unmapping ("0"to disable heap shrinking);GC_MARKERS - explicitly set the number of parallel "marker" threads (ifthe garbage collector supports parallel marking).Appendix D: C macros used to control compilation------------------------------------------------/* Include "config.h" file */#define HAVE_CONFIG_H/* Allow Win32 API usage where necessary */#define JCGO_WIN32/* Allow OS/2 platform API usage where necessary */#define JCGO_OS2/* Only if JCGO_THREADS is defined, and JCGO_OS2 and JCGO_WIN32 are not defined: use Solaris SunOS native threads (instead of POSIX threads) */#define JCGO_SOLTHR/* Only if JCGO_THREADS is defined: all threads are allowed to be running fully parallel (otherwise, the threads are non-preemptive except for I/O operations) */#define JCGO_PARALLEL/* Only if JCGO_THREADS and JCGO_PARALLEL are defined: do not use atomic fetch() and store() operations to access Java volatile fields (i.e., treat Java "volatile" access modifier as C one) */#define JCGO_CVOLATILE/* Only if JCGO_THREADS is defined: assume that the standard C library is not thread-safe (i.e., C system calls are non-reentrant ones) */#define JCGO_NOMTCLIB/* Only if JCGO_NOFP is not defined: floating-point variables have the reversed byte-order (the opposite to the order of bytes in an integer variable) */#define JCGO_REVFLOAT/* Only if JCGO_NOFP is not defined: allow advanced math functions (cbrt, expm1, floorf, fmodf, log1p) usage where necessary */#define JCGO_MATHEXT/* Only if JCGO_NOFP is not defined: assume that C floating-point division and comparison operations work exactly in accordance to the corresponding IEEE standard */#define JCGO_FPFAST/* Only if JCGO_NOFP is not defined: assume C math.h functions behavior match Java Math class methods specification */#define JCGO_FASTMATH/* Define (or allow to define if used for compiling C files of the JCGO "native" library) Unicode "wmain" function as the program entry point (instead of "main") */#define JCGO_WMAIN/* Only if JCGO_NATSEP is not defined: use Unicode (wchar_t) functions of the file API (of the standard C library) where appropriate (otherwise, only ASCII (multibyte) functions are used) */#define JCGO_SYSWCHAR/* Only if JCGO_NATSEP is not defined and JCGO_SYSWCHAR is defined: choose whether to use Unicode or ASCII (multibyte) functions of the file API (of the standard C library) at run-time (useful for Win32 platform) */#define JCGO_SYSDUALW/* Only if JCGO_NATSEP and JCGO_UTFWCTOMB are not defined: use mbstowcs() and wcstombs() (instead of mbtowc() and wctomb(), respectively) for the multibyte-to-Java and Java-to-multibyte string conversions (useful for WinCE platforms) */#define JCGO_DOWCSTOMBS/* Only if JCGO_NATSEP is not defined: assume native multi-byte encoding is UTF-8 (useful if mbtowc/wctomb and mbstowcs/wcstombs are missing) */#define JCGO_UTFWCTOMB/* Only if JCGO_NATSEP is not defined: get some Java system properties using Win32 API directly (useful for WinCE platforms) */#define JCGO_WINEXINFO/* Only if JCGO_NATSEP is not defined: use Win32 file I/O API directly (useful for WinCE platforms) */#define JCGO_WINFILE/* Use C "stdout" instead of "stderr" file descriptor for the Java "System.err" stream (and for fatal runtime errors outputting) */#define JCGO_ERRSTDOUT/* Only if JCGO_NOFILES is not defined: redirect (or allow to redirect if used for compiling C files of the JCGO "native" library) C "stderr" (and "stdout" if JCGO_ERRSTDOUT is defined too) stream to ".log" file (only if "STDERROUT_LOGFILE" environment variable is set specifying the log file name or if the executable-name-based log file already exists) */#define JCGO_ERRTOLOG/* Only if JCGO_ERRTOLOG is defined: force C "stderr" (and "stdout" if JCGO_ERRSTDOUT is defined too) stream redirection (the log file will be created at the program start-up) */#define JCGO_TOLOGFORCE/* Only if JCGO_NATSEP, JCGO_NOFILES and JCGO_WINFILE are not defined: use _findfirst/_findnext/_findclose with handle and _finddata_t data structure for directory scanning */#define JCGO_FFDATA/* Only if JCGO_NATSEP, JCGO_NOFILES and JCGO_WINFILE are not defined: use findfirst/findnext with ffblk data structure for directory scanning (otherwise, opendir/readdir/closedir are used if JCGO_FFDATA and JCGO_FFDOS are not defined) */#define JCGO_FFBLK/* Only if JCGO_NATSEP, JCGO_NOFILES and JCGO_WINFILE are not defined: use _dos_findfirst/_dos_findnext with find_t data structure for directory scanning (only if JCGO_FFDATA and JCGO_FFBLK are not defined) */#define JCGO_FFDOS/* Only if JCGO_NATSEP, JCGO_NOFILES and JCGO_WINFILE are not defined: use file I/O functions with large-file support */#define JCGO_LARGEFILE/* Only if JCGO_NATSEP, JCGO_NOFILES, JCGO_UNIX and JCGO_WINFILE are not defined, and JCGO_LARGEFILE is defined: use _chsize_s() file I/O API call (instead of chsize() or SetEndOfFile() ones) */#define JCGO_FCHSIZES/* Only if JCGO_NATSEP is not defined: use Unix-style file naming conventions (target for Unix platform) */#define JCGO_UNIFSYS/* Only if JCGO_NATSEP and JCGO_UNIFSYS are not defined: target for a single-root file system (required for WinCE platforms) */#define JCGO_ONEROOTFS/* Only if JCGO_NATSEP and JCGO_NOFILES are not defined, and JCGO_UNIFSYS is defined: target the JCGO "native" library for ancient Mac OS (Darwin) platforms */#define JCGO_MACOSX/* Only if JCGO_NATSEP and JCGO_WINFILE are not defined, and JCGO_EXEC is defined: use Unix process execution conventions (target for Unix platform) */#define JCGO_UNIPROC/* Only if JCGO_NATSEP is not defined: allow execution (spawning) of child processes */#define JCGO_EXEC/* Only if JCGO_NATSEP is not defined: allow Internet networking capabilities to be used */#define JCGO_INET/* Only if JCGO_NATSEP is not defined, and JCGO_INET and JCGO_WIN32 are defined: use old WinSock v1.1 interface (instead of WinSock v2.2) */#define JCGO_OLDWSOCK/* Only if JCGO_NATSEP and JCGO_WIN32 are not defined, and JCGO_INET is defined: use GNU-style (BSD) gethostbyaddr_r() and gethostbyname_r() reentrant functions (otherwise, non-reentrant variants of these functions are used if JCGO_SYSVNETDB is not defined) */#define JCGO_GNUNETDB/* Only if JCGO_NATSEP, JCGO_WIN32 and JCGO_GNUNETDB are not defined, and JCGO_INET is defined: use SysV-style (Solaris SunOS) gethostbyaddr_r() and gethostbyname_r() reentrant functions (otherwise, non-reentrant variants of these functions are used) */#define JCGO_SYSVNETDB/* Only if JCGO_NATSEP, JCGO_NOTIME and JCGO_WINFILE are not defined: use clock_gettime(CLOCK_MONOTONIC) to obtain nanoTime() value if possible; only if JCGO_THREADS is defined, and JCGO_WIN32 and JCGO_OS2 are not defined: use clock_gettime(CLOCK_REALTIME) instead of gettimeofday() for timed wait */#define JCGO_CLOCKGETTM/* Only if JCGO_NATSEP is not defined: do not use any C time-related functions */#define JCGO_NOTIME/* Only if JCGO_NATSEP is not defined: do not provide any access to the underlying file system */#define JCGO_NOFILES/* Only if JCGO_NATSEP and JCGO_NOFILES are not defined: assume the underlying file system has no concept of a current working directory */#define JCGO_NOCWDIR/* Only if JCGO_NATSEP, JCGO_NOFILES, JCGO_NOTIME and JCGO_WINFILE are not defined: do not use C "utimbuf" struct and utime() system call */#define JCGO_NOUTIMBUF/* Only if JCGO_NATSEP and JCGO_NOTIME are not defined: do not treat tv_sec value returned by gettimeofday() and ftime() as unsigned */#define JCGO_TIMEALLOWNEG/* Only if JCGO_NATSEP and JCGO_NOFILES are not defined: do not use realpath() C library call */#define JCGO_NOREALPATH/* Only if JCGO_NATSEP is not defined: do not query system name and release version from OS */#define JCGO_NOSYSNAME/* Do not print any message on fatal runtime errors */#define JCGO_NOFATALMSG/* Compile every produced C file separately */#define JCGO_SEPARATED/* Do not compile C files of the JCGO "native" library */#define JCGO_NATSEP/* Do not support and use Java Native Interface (JNI) */#define JCGO_NOJNI/* Only if JCGO_NOJNI is not defined: do not support JNI_CreateJavaVM() and AttachCurrentThread() of JNIInvokeInterface */#define JCGO_NOCREATJVM/* Only if JCGO_CHKCAST or JCGO_INDEXCHK, or JCGO_SFTNULLP, or JCGO_HWNULLZ is defined: abort execution (with the corresponding "assertion violated" message) instead of throwing array-index-out-of-bounds, array-store, class-cast and null-pointer exceptions by VM runtime */#define JCGO_RTASSERT/* Abort the application (on JCGO runtime fatal error) via abort() instead of exit(-1) call. */#define JCGO_TRUEABORT/* Enable Java assertions; it may be defined or undefined independently for every class if JCGO_SEPARATED is defined */#define JCGO_ASSERTION/* Only if JCGO_STDCLINIT is not defined: turn on class proper initialization order checking; it may be defined or undefined independently for every class if JCGO_SEPARATED is defined */#define JCGO_CLINITCHK/* Force index checking for every array access; it may be defined or undefined independently for every class if JCGO_SEPARATED is defined */#define JCGO_INDEXCHK/* Force type checking for all class cast operations and for all object arrays element storing; it may be defined or undefined independently for every class if JCGO_SEPARATED is defined */#define JCGO_CHKCAST/* Use (force) explicit software null-pointer dereference checking (instead of using hardware pointer checking support); it may be defined or undefined independently for every class if JCGO_SEPARATED is defined */#define JCGO_SFTNULLP/* Only if JCGO_SFTNULLP and JCGO_NOSEGV are not defined: always try to dereference an object pointer with zero (or nearly zero) offset first (thus allowing hardware null-pointer dereference checking even if it is limited); it may be defined or undefined independently for every class if JCGO_SEPARATED is defined */#define JCGO_HWNULLZ/* Do not use SIGSEGV and SIGBUS signals by VM runtime (disable hardware null-pointer dereference checking) */#define JCGO_NOSEGV/* Do not change default handlers for SIGINT and SIGTERM signals */#define JCGO_NOCTRLC/* Use Unix platform basic API */#define JCGO_UNIX/* Produce code supporting multi-threaded execution */#define JCGO_THREADS/* Use the standard class on-demand initialization (otherwise, all classes are initialized at program start-up); it should be used (at least) when the JCGO translator warns that it cannot determine proper initialization order for one or more classes */#define JCGO_STDCLINIT/* Use Structured Exception Handling (SEH) instead of setjmp() to implement Java exception handling (works only if jumping out of a __finally block has Java-like behavior during termination handling) */#define JCGO_SEHTRY/* Use C int (instead of C unsigned char) type for the Java boolean type (note that JNI is affected too, so JCGO_BOOLINT should not be normally defined if JCGO_NOJNI is not defined) */#define JCGO_BOOLINT/* Use extended C __int8, __int16, __int32, __int64 types for the Java byte, short and char, int, long types respectively (with the exceptions stated for JCGO_INTFIT, JCGO_USELONG macros) */#define JCGO_INTNN/* Assume sizeof(int) is 4, so use C int (not long or __int32) for the Java int type */#define JCGO_INTFIT/* Use C long for the Java long type (otherwise, use either C __int64 or long long type) */#define JCGO_USELONG/* Only if JCGO_USELONG is not defined: use "LL" suffix for __int64 type values or "i64" suffix for long long type values (vice versa, otherwise) */#define JCGO_INVLL/* Do not use C float and double types and floating-point arithmetics at all (in this case the Java float and double types are represented by the Java int and long types respectively) */#define JCGO_NOFP/* Only if JCGO_NOFP is not defined: use C long double type (to represent Java double type and perform all floating-point calculations with the extended precision) instead of the (normal) double type (note that JNI is affected too, so JCGO_LONGDBL should not be normally defined if JCGO_NOJNI is not defined) */#define JCGO_LONGDBL/* Only if JCGO_SEPARATED is not defined: do not mark Java functions as inline that are used before their definitions in the generated C code (no "forward" inlining) */#define JCGO_NOFRWINL/* Do not use "const" keyword for immutable C struct members (fields) */#define JCGO_NOFLDCONST/* Prefix JNI functions names with additional "_" (underscore) */#define JCGO_JNIUSCORE/* Only if JCGO_THREADS and JCGO_WIN32 are defined: allow to switch the system timer to the highest possible resolution when needed */#define JCGO_TIMEHIRES/* Only if JCGO_THREADS is defined, and all of JCGO_WIN32, JCGO_OS2 and JCGO_SOLTHR are not defined: use PThread timed wait based on monotonic clock */#define JCGO_MONOTWAIT/* Only if JCGO_THREADS is defined, and JCGO_OS2 or JCGO_WIN32 is defined: use OS CreateThread() API call instead of C _beginthread() */#define JCGO_CREATHREAD/* Allow to allocate and access "huge" arrays (occupying multiple adjacent memory segments); only for "large" data address models */#define JCGO_HUGEARR/* Only if JCGO_NOGC is not defined and JCGO_THREADS is defined: use (GC_get_parallel() + 1) value as the number of available CPUs */#define JCGO_GCGETPAR/* Do not use memory garbage collector, use the standard calloc instead, so that the allocated memory is never reclaimed (and finalizers are never executed) */#define JCGO_NOGC/* Store and use the GCJ-style length-based type descriptors (useful only if JCGO_NOGC is not defined) to make garbage collection a bit more accurate */#define JCGO_USEGCJ/* Only if JCGO_NOGC is not defined: clear "static data roots" preset by the garbage collector at start-up and disable dynamic library data segments registering */#define JCGO_GCRESETDLS/* Only if JCGO_NOGC is not defined: do not turn off "all-interior-pointers" recognition mode of the garbage collector */#define JCGO_GCALLINTER/* Only if JCGO_NOGC is not defined: force (explicitly turn on) GC incremental mode (should be used with great care unless JCGO_NOSEGV or JCGO_WIN32 is defined) */#define JCGO_GCINC/* Only if JCGO_NOGC is not defined: use shared version of GC library */#define GC_DLL/* Only if JCGO_NOGC is not defined: use the debug version of GC malloc */#define GC_DEBUG/* Only if JCGO_NOGC is not defined and JCGO_THREADS is defined: do not redirect C library thread creation calls to GC (use explicit GC thread registration instead) */#define GC_NO_THREAD_REDIRECTS/* Only if JCGO_NOGC is not defined: force immediate memory unmapping (if supported) on explicitly-initiated garbage collections by default */#define GC_FORCE_UNMAP_ON_GCOLLECT/* Only if JCGO_NOGC is not defined: set the desired initial heap size (in bytes) */#define GC_INITIAL_HEAP_SIZE 1024*1024/* Only if JCGO_NOGC is not defined: explicitly specify GC_free_space_divisor value (otherwise, the default value is used) */#define GC_FREE_SPACE_DIVISOR 5/* Only if JCGO_NOGC is not defined: explicitly specify calling convention for the GC API functions */#define GC_CALL __cdecl/* Only if JCGO_NOGC is not defined: explicitly specify an alternate calling convention for the GC API user callbacks */#define GC_CALLBACK __cdecl/* Do not use C "const" keyword */#define CONST /**//* Do not inline functions */#define INLINE /**//* Do not use C "static" keyword for functions (i.e., use external linkage for all functions) */#define STATIC /**//* Use internal linkage for some C functions that should normally have external linkage (visibility) */#define EXTRASTATIC static/* Use "dllimport" declaration modifier for imported functions */#define JNIIMPORT __declspec(dllimport)/* Use "dllexport" declaration modifier for exported functions */#define JNIEXPORT __declspec(dllexport)/* Only if JCGO_NOJNI is not defined: explicitly use "dllexport" for Java VM Invocation API functions */#define JNIEXPORT_INVOKE __declspec(dllexport)/* Use "static" declaration modifier for some (considerable) JNU functions (instead of JNIEXPORT modifier) */#define JNUBIGEXPORT static/* Use "stdcall" calling convention for JNI library */#define JNICALL __stdcall/* Only if JCGO_NOJNI is not defined: explicitly specify "stdcall" calling convention for Java VM Invocation API functions */#define JNICALL_INVOKE __stdcall/* Do not use "fast calling" convention explicitly */#define CFASTCALL /**//* Do not use "cdecl" calling convention for C runtime library callbacks */#define CLIBDECL /**//* Do not perform explicit initialization of the floating-point module */#define FPINIT /**//* Only if JCGO_THREADS is defined: do not perform explicit initialization of the C threads library */#define THREADSINIT /**//* Only if JCGO_THREADS is defined: explicitly specify default stack size for non-main threads (zero for system-specific stack size) */#define THREADSTACKSZ 0/* Only if JCGO_SEPARATED is not defined: do not use C "static" storage class for global variables (i.e., use external linkage for all global data) */#define STATICDATA /**//* Only if JCGO_SEPARATED is not defined: override C storage class (specified by STATICDATA) for global GC-sensitive variables (useful only if JCGO_NOGC is not defined) */#define GCSTATICDATA /**//* Only if JCGO_NOGC is not defined: explicitly instruct the garbage collector about the first GC-sensitive (i.e., which could hold pointers to heap-allocated Java objects) symbol placed to "data" section by the target code linker */#define GCDATAFIRSTSYM java_lang_String__class/* Only if JCGO_NOGC is not defined: explicitly instruct the garbage collector about the last GC-sensitive symbol placed to "data" section by the target code linker */#define GCDATALASTSYM jcgo_noTypesClassArr/* Only if JCGO_NOGC is not defined: explicitly instruct the garbage collector about the first GC-sensitive symbol placed to "bss" section by the target code linker */#define GCBSSFIRSTSYM jcgo_initialized/* Only if JCGO_NOGC is not defined: explicitly instruct the garbage collector about the last GC-sensitive symbol placed to "bss" section by the target code linker */#define GCBSSLASTSYM jcgo_globData/* Specify an alternate section to place all C global variables which are non-zero initially and, besides, could not hold pointers to any heap-allocated Java object during run time (useful only if JCGO_NOGC is not defined); it may be defined or undefined independently for every class if JCGO_SEPARATED is defined */#define ATTRIBNONGC __attribute__((section(".dataord")))/* Specify an alternate section to place all C global non-zero variables which could hold pointers to heap-allocated Java objects (useful only if JCGO_NOGC is not defined and JCGO_GCRESETDLS is defined; should be used instead of ATTRIBNONGC when the target C compiler does not place the read-only data into a separate program section) */#define ATTRIBGCDATA __attribute__((section(".datagc")))/* Specify an alternate section to place all C global variables which are initialized to zero and could hold pointers to heap-allocated Java objects (useful only if JCGO_NOGC is not defined and JCGO_GCRESETDLS is defined) */#define ATTRIBGCBSS __attribute__((section(".bss4gc")))/* Ignore GNU C 'malloc' attribute (for some memory allocation internal functions) */#define ATTRIBMALLOC /**//* Ignore 'noreturn' attribute of the Java 'throw' statement */#define DECLSPECNORET /**//* Ignore branch probabilities specified via GNU C __builtin_expect */#define BUILTINEXPECTR /**//* Explicitly specify the decl and the name of C main entry function */#define MAINENTRY int/**/__cdecl/**/main/* Prototype all "JNI_OnLoad" and "JNI_OnUnload" external functions (using JNIONLOAD and JNIONUNLOAD macros) those names are specified in either JNIONLOADLIST or JNIONUNLOADLIST lists */#define JNIONLOADDECLS JNIONLOAD(JNI_OnLoad1)JNIONUNLOAD(JNI_OnUnload1)/* Specify comma-separated names list of "JNI_OnLoad" functions to call */#define JNIONLOADLIST JNI_OnLoad1,JNI_OnLoad2/* Specify comma-separated names list of "JNI_OnUnload" functions to call */#define JNIONUNLOADLIST JNI_OnUnload1,JNI_OnUnload2/* Link native package.Class.jniFunc() to a stub (aborting the execution) instead of linking it to the external Java_package_Class_jniFunc() */#define NOJAVA_package_Class_jniFunc/* Specify the default value for "JAVA_PROPS" environment variable (if the latter is unset); the string value opening quote must be prefixed with 'L' if and only if JCGO_WMAIN is defined */#define JAVADEFPROPS ""                          --- [ End of File ] ---