diff -r 378aa3362868 -r 320a714614e9 jdk/src/macosx/bin/jexec.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/src/macosx/bin/jexec.c Tue Mar 06 20:34:38 2012 +0000 @@ -0,0 +1,239 @@ +/* + * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. Oracle designates this + * particular file as subject to the "Classpath" exception as provided + * by Oracle in the LICENSE file that accompanied this code. + * + * This code 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 + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +/* + * jexec for J2SE + * + * jexec is used by the system to allow execution of JAR files. + * Essentially jexec needs to run java and + * needs to be a native ISA executable (not a shell script), although + * this native ISA executable requirement was a mistake that will be fixed. + * ( is sparc or i386 or amd64). + * + * When you execute a jar file, jexec is executed by the system as follows: + * /usr/java/jre/lib//jexec -jar JARFILENAME + * so this just needs to be turned into: + * /usr/java/jre/bin/java -jar JARFILENAME + * + * Solaris systems (new 7's and all 8's) will be looking for jexec at: + * /usr/java/jre/lib//jexec + * Older systems may need to add this to their /etc/system file: + * set javaexec:jexec="/usr/java/jre/lib//jexec" + * and reboot the machine for this to work. + * + * This source should be compiled as: + * cc -o jexec jexec.c + * + * And jexec should be placed at the following location of the installation: + * /jre/lib//jexec (for Solaris) + * /lib/jexec (for Linux) + * + * NOTE: Unless is the "default" JDK on the system + * (i.e. /usr/java -> ), this jexec will not be + * found. The 1.2 java is only the default on Solaris 8 and + * on systems where the 1.2 packages were installed and no 1.1 + * java was found. + * + * NOTE: You must use 1.2 jar to build your jar files. The system + * doesn't seem to pick up 1.1 jar files. + * + * NOTE: We don't need to set LD_LIBRARY_PATH here, even though we + * are running the actual java binary because the java binary will + * look for it's libraries through it's own runpath, which uses + * $ORIGIN. + * + * NOTE: This jexec should NOT have any special .so library needs because + * it appears that this executable will NOT get the $ORIGIN of jexec + * but the $ORIGIN of the jar file being executed. Be careful to keep + * this program simple and with no .so dependencies. + */ + +#include +#include +#include +#include +#include +#include + +static const int CRAZY_EXEC = ENOEXEC; +static const int BAD_MAGIC = ENOEXEC; + +static const char * BAD_EXEC_MSG = "jexec failed"; +static const char * CRAZY_EXEC_MSG = "missing args"; +static const char * MISSING_JAVA_MSG = "can't locate java"; +static const char * UNKNOWN_ERROR = "unknown error"; + +/* Define a constant that represents the number of directories to pop off the + * current location to find the java binary */ +static const int RELATIVE_DEPTH = 3; + +/* path to java after popping */ +static const char * BIN_PATH = "/bin/java"; + +/* flag used when running JAR files */ +static const char * JAR_FLAG = "-jar"; + +int main(int argc, const char * argv[]); +void errorExit(int error, const char * message); +int getJavaPath(const char * path, char * buf, int depth); + +/* + * This is the main entry point. This program (jexec) will attempt to execute + * a JAR file by finding the Java program (java), relative to its own location. + * The exact location of the Java program depends on the platform, i.e. + * + * /jre/lib//jexec (for Solaris) + * /lib/jexec (for Linux JDK) + * + * Once the Java program is found, this program copies any remaining arguments + * into another array, which is then used to exec the Java program. + * + * On Linux this program does some additional steps. When copying the array of + * args, it is necessary to insert the "-jar" flag between arg[0], the program + * name, and the original arg[1], which is presumed to be a path to a JAR file. + * It is also necessary to verify that the original arg[1] really is a JAR file. + * (These steps are unnecessary on Solaris because they are taken care of by + * the kernel.) + */ +int main(int argc, const char * argv[]) { + /* We need to exec the original arguments using java, instead of jexec. + * Also, for Linux, it is necessary to add the "-jar" argument between + * the new arg[0], and the old arg[1]. To do this we will create a new + * args array. */ + char java[PATH_MAX + 1]; /* path to java binary */ + const char ** nargv = NULL; /* new args array */ + int nargc = 0; /* new args array count */ + int argi = 0; /* index into old array */ + + /* Make sure we have something to work with */ + if ((argc < 1) || (argv == NULL)) { + /* Shouldn't happen... */ + errorExit(CRAZY_EXEC, CRAZY_EXEC_MSG); + } + + /* Get the path to the java binary, which is in a known position relative + * to our current position, which is in argv[0]. */ + if (getJavaPath(argv[argi++], java, RELATIVE_DEPTH) != 0) { + errorExit(errno, MISSING_JAVA_MSG); + } + + nargv = (const char **) malloc((argc + 2) * (sizeof (const char *))); + nargv[nargc++] = java; + + if (argc >= 2) { + const char * jarfile = argv[argi++]; + const char * message = NULL; + + /* the next argument is the path to the JAR file */ + nargv[nargc++] = jarfile; + } + + /* finally copy any remaining arguments */ + while (argi < argc) { + nargv[nargc++] = argv[argi++]; + } + + /* finally add one last terminating null */ + nargv[nargc++] = NULL; + + /* It's time to exec the java binary with the new arguments. It + * is possible that we've reached this point without actually + * having a JAR file argument (i.e. if argc < 2), but we still + * want to exec the java binary, since that will take care of + * displaying the correct usage. */ + execv(java, (char * const *) nargv); + + /* If the exec worked, this process would have been replaced + * by the new process. So any code reached beyond this point + * implies an error in the exec. */ + free(nargv); + errorExit(errno, BAD_EXEC_MSG); + return 0; // keep the compiler happy +} + + +/* + * Exit the application by setting errno, and writing a message. + * + * Parameters: + * error - errno is set to this value, and it is used to exit. + * message - the message to write. + */ +void errorExit(int error, const char * message) { + if (error != 0) { + errno = error; + perror((message != NULL) ? message : UNKNOWN_ERROR); + } + + exit((error == 0) ? 0 : 1); +} + + +/* + * Get the path to the java binary that should be relative to the current path. + * + * Parameters: + * path - the input path that the java binary that should be relative to. + * buf - a buffer of size PATH_MAX or greater that the java path is + * copied to. + * depth - the number of names to trim off the current path, including the + * name of this program. + * + * Returns: + * This function returns 0 on success; otherwise it returns the value of + * errno. + */ +int getJavaPath(const char * path, char * buf, int depth) { + int result = 0; + + /* Get the full path to this program. Depending on whether this is Solaris + * or Linux, this will be something like, + * + * /jre/lib//jexec (for Solaris) + * /lib/jexec (for Linux) + */ + if (realpath(path, buf) != NULL) { + int count = 0; + + /* Pop off the filename, and then subdirectories for each level of + * depth */ + for (count = 0; count < depth; count++) { + *(strrchr(buf, '/')) = '\0'; + } + + /* Append the relative location of java, creating something like, + * + * /jre/bin/java (for Solaris) + * /bin/java (for Linux) + */ + strcat(buf, BIN_PATH); + } + else { + /* Failed to get the path */ + result = errno; + } + + return (result); +}