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diff --git a/Documentation/java.txt b/Documentation/java.txt deleted file mode 100644 index e6a723281547..000000000000 --- a/Documentation/java.txt +++ /dev/null @@ -1,396 +0,0 @@ - Java(tm) Binary Kernel Support for Linux v1.03 - ---------------------------------------------- - -Linux beats them ALL! While all other OS's are TALKING about direct -support of Java Binaries in the OS, Linux is doing it! - -You can execute Java applications and Java Applets just like any -other program after you have done the following: - -1) You MUST FIRST install the Java Developers Kit for Linux. - The Java on Linux HOWTO gives the details on getting and - installing this. This HOWTO can be found at: - - ftp://sunsite.unc.edu/pub/Linux/docs/HOWTO/Java-HOWTO - - You should also set up a reasonable CLASSPATH environment - variable to use Java applications that make use of any - nonstandard classes (not included in the same directory - as the application itself). - -2) You have to compile BINFMT_MISC either as a module or into - the kernel (CONFIG_BINFMT_MISC) and set it up properly. - If you choose to compile it as a module, you will have - to insert it manually with modprobe/insmod, as kmod - cannot easily be supported with binfmt_misc. - Read the file 'binfmt_misc.txt' in this directory to know - more about the configuration process. - -3) Add the following configuration items to binfmt_misc - (you should really have read binfmt_misc.txt now): - support for Java applications: - ':Java:M::\xca\xfe\xba\xbe::/usr/local/bin/javawrapper:' - support for executable Jar files: - ':ExecutableJAR:E::jar::/usr/local/bin/jarwrapper:' - support for Java Applets: - ':Applet:E::html::/usr/bin/appletviewer:' - or the following, if you want to be more selective: - ':Applet:M::<!--applet::/usr/bin/appletviewer:' - - Of course you have to fix the path names. The path/file names given in this - document match the Debian 2.1 system. (i.e. jdk installed in /usr, - custom wrappers from this document in /usr/local) - - Note, that for the more selective applet support you have to modify - existing html-files to contain <!--applet--> in the first line - ('<' has to be the first character!) to let this work! - - For the compiled Java programs you need a wrapper script like the - following (this is because Java is broken in case of the filename - handling), again fix the path names, both in the script and in the - above given configuration string. - - You, too, need the little program after the script. Compile like - gcc -O2 -o javaclassname javaclassname.c - and stick it to /usr/local/bin. - - Both the javawrapper shellscript and the javaclassname program - were supplied by Colin J. Watson <cjw44@cam.ac.uk>. - -====================== Cut here =================== -#!/bin/bash -# /usr/local/bin/javawrapper - the wrapper for binfmt_misc/java - -if [ -z "$1" ]; then - exec 1>&2 - echo Usage: $0 class-file - exit 1 -fi - -CLASS=$1 -FQCLASS=`/usr/local/bin/javaclassname $1` -FQCLASSN=`echo $FQCLASS | sed -e 's/^.*\.\([^.]*\)$/\1/'` -FQCLASSP=`echo $FQCLASS | sed -e 's-\.-/-g' -e 's-^[^/]*$--' -e 's-/[^/]*$--'` - -# for example: -# CLASS=Test.class -# FQCLASS=foo.bar.Test -# FQCLASSN=Test -# FQCLASSP=foo/bar - -unset CLASSBASE - -declare -i LINKLEVEL=0 - -while :; do - if [ "`basename $CLASS .class`" == "$FQCLASSN" ]; then - # See if this directory works straight off - cd -L `dirname $CLASS` - CLASSDIR=$PWD - cd $OLDPWD - if echo $CLASSDIR | grep -q "$FQCLASSP$"; then - CLASSBASE=`echo $CLASSDIR | sed -e "s.$FQCLASSP$.."` - break; - fi - # Try dereferencing the directory name - cd -P `dirname $CLASS` - CLASSDIR=$PWD - cd $OLDPWD - if echo $CLASSDIR | grep -q "$FQCLASSP$"; then - CLASSBASE=`echo $CLASSDIR | sed -e "s.$FQCLASSP$.."` - break; - fi - # If no other possible filename exists - if [ ! -L $CLASS ]; then - exec 1>&2 - echo $0: - echo " $CLASS should be in a" \ - "directory tree called $FQCLASSP" - exit 1 - fi - fi - if [ ! -L $CLASS ]; then break; fi - # Go down one more level of symbolic links - let LINKLEVEL+=1 - if [ $LINKLEVEL -gt 5 ]; then - exec 1>&2 - echo $0: - echo " Too many symbolic links encountered" - exit 1 - fi - CLASS=`ls --color=no -l $CLASS | sed -e 's/^.* \([^ ]*\)$/\1/'` -done - -if [ -z "$CLASSBASE" ]; then - if [ -z "$FQCLASSP" ]; then - GOODNAME=$FQCLASSN.class - else - GOODNAME=$FQCLASSP/$FQCLASSN.class - fi - exec 1>&2 - echo $0: - echo " $FQCLASS should be in a file called $GOODNAME" - exit 1 -fi - -if ! echo $CLASSPATH | grep -q "^\(.*:\)*$CLASSBASE\(:.*\)*"; then - # class is not in CLASSPATH, so prepend dir of class to CLASSPATH - if [ -z "${CLASSPATH}" ] ; then - export CLASSPATH=$CLASSBASE - else - export CLASSPATH=$CLASSBASE:$CLASSPATH - fi -fi - -shift -/usr/bin/java $FQCLASS "$@" -====================== Cut here =================== - - -====================== Cut here =================== -/* javaclassname.c - * - * Extracts the class name from a Java class file; intended for use in a Java - * wrapper of the type supported by the binfmt_misc option in the Linux kernel. - * - * Copyright (C) 1999 Colin J. Watson <cjw44@cam.ac.uk>. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - */ - -#include <stdlib.h> -#include <stdio.h> -#include <stdarg.h> -#include <sys/types.h> - -/* From Sun's Java VM Specification, as tag entries in the constant pool. */ - -#define CP_UTF8 1 -#define CP_INTEGER 3 -#define CP_FLOAT 4 -#define CP_LONG 5 -#define CP_DOUBLE 6 -#define CP_CLASS 7 -#define CP_STRING 8 -#define CP_FIELDREF 9 -#define CP_METHODREF 10 -#define CP_INTERFACEMETHODREF 11 -#define CP_NAMEANDTYPE 12 - -/* Define some commonly used error messages */ - -#define seek_error() error("%s: Cannot seek\n", program) -#define corrupt_error() error("%s: Class file corrupt\n", program) -#define eof_error() error("%s: Unexpected end of file\n", program) -#define utf8_error() error("%s: Only ASCII 1-255 supported\n", program); - -char *program; - -long *pool; - -u_int8_t read_8(FILE *classfile); -u_int16_t read_16(FILE *classfile); -void skip_constant(FILE *classfile, u_int16_t *cur); -void error(const char *format, ...); -int main(int argc, char **argv); - -/* Reads in an unsigned 8-bit integer. */ -u_int8_t read_8(FILE *classfile) -{ - int b = fgetc(classfile); - if(b == EOF) - eof_error(); - return (u_int8_t)b; -} - -/* Reads in an unsigned 16-bit integer. */ -u_int16_t read_16(FILE *classfile) -{ - int b1, b2; - b1 = fgetc(classfile); - if(b1 == EOF) - eof_error(); - b2 = fgetc(classfile); - if(b2 == EOF) - eof_error(); - return (u_int16_t)((b1 << 8) | b2); -} - -/* Reads in a value from the constant pool. */ -void skip_constant(FILE *classfile, u_int16_t *cur) -{ - u_int16_t len; - int seekerr = 1; - pool[*cur] = ftell(classfile); - switch(read_8(classfile)) - { - case CP_UTF8: - len = read_16(classfile); - seekerr = fseek(classfile, len, SEEK_CUR); - break; - case CP_CLASS: - case CP_STRING: - seekerr = fseek(classfile, 2, SEEK_CUR); - break; - case CP_INTEGER: - case CP_FLOAT: - case CP_FIELDREF: - case CP_METHODREF: - case CP_INTERFACEMETHODREF: - case CP_NAMEANDTYPE: - seekerr = fseek(classfile, 4, SEEK_CUR); - break; - case CP_LONG: - case CP_DOUBLE: - seekerr = fseek(classfile, 8, SEEK_CUR); - ++(*cur); - break; - default: - corrupt_error(); - } - if(seekerr) - seek_error(); -} - -void error(const char *format, ...) -{ - va_list ap; - va_start(ap, format); - vfprintf(stderr, format, ap); - va_end(ap); - exit(1); -} - -int main(int argc, char **argv) -{ - FILE *classfile; - u_int16_t cp_count, i, this_class, classinfo_ptr; - u_int8_t length; - - program = argv[0]; - - if(!argv[1]) - error("%s: Missing input file\n", program); - classfile = fopen(argv[1], "rb"); - if(!classfile) - error("%s: Error opening %s\n", program, argv[1]); - - if(fseek(classfile, 8, SEEK_SET)) /* skip magic and version numbers */ - seek_error(); - cp_count = read_16(classfile); - pool = calloc(cp_count, sizeof(long)); - if(!pool) - error("%s: Out of memory for constant pool\n", program); - - for(i = 1; i < cp_count; ++i) - skip_constant(classfile, &i); - if(fseek(classfile, 2, SEEK_CUR)) /* skip access flags */ - seek_error(); - - this_class = read_16(classfile); - if(this_class < 1 || this_class >= cp_count) - corrupt_error(); - if(!pool[this_class] || pool[this_class] == -1) - corrupt_error(); - if(fseek(classfile, pool[this_class] + 1, SEEK_SET)) - seek_error(); - - classinfo_ptr = read_16(classfile); - if(classinfo_ptr < 1 || classinfo_ptr >= cp_count) - corrupt_error(); - if(!pool[classinfo_ptr] || pool[classinfo_ptr] == -1) - corrupt_error(); - if(fseek(classfile, pool[classinfo_ptr] + 1, SEEK_SET)) - seek_error(); - - length = read_16(classfile); - for(i = 0; i < length; ++i) - { - u_int8_t x = read_8(classfile); - if((x & 0x80) || !x) - { - if((x & 0xE0) == 0xC0) - { - u_int8_t y = read_8(classfile); - if((y & 0xC0) == 0x80) - { - int c = ((x & 0x1f) << 6) + (y & 0x3f); - if(c) putchar(c); - else utf8_error(); - } - else utf8_error(); - } - else utf8_error(); - } - else if(x == '/') putchar('.'); - else putchar(x); - } - putchar('\n'); - free(pool); - fclose(classfile); - return 0; -} -====================== Cut here =================== - - -====================== Cut here =================== -#!/bin/bash -# /usr/local/java/bin/jarwrapper - the wrapper for binfmt_misc/jar - -java -jar $1 -====================== Cut here =================== - - -Now simply chmod +x the .class, .jar and/or .html files you want to execute. -To add a Java program to your path best put a symbolic link to the main -.class file into /usr/bin (or another place you like) omitting the .class -extension. The directory containing the original .class file will be -added to your CLASSPATH during execution. - - -To test your new setup, enter in the following simple Java app, and name -it "HelloWorld.java": - - class HelloWorld { - public static void main(String args[]) { - System.out.println("Hello World!"); - } - } - -Now compile the application with: - javac HelloWorld.java - -Set the executable permissions of the binary file, with: - chmod 755 HelloWorld.class - -And then execute it: - ./HelloWorld.class - - -To execute Java Jar files, simple chmod the *.jar files to include -the execution bit, then just do - ./Application.jar - - -To execute Java Applets, simple chmod the *.html files to include -the execution bit, then just do - ./Applet.html - - -originally by Brian A. Lantz, brian@lantz.com -heavily edited for binfmt_misc by Richard Günther -new scripts by Colin J. Watson <cjw44@cam.ac.uk> -added executable Jar file support by Kurt Huwig <kurt@iku-netz.de> - |