/*

 * 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

 * particular file as subject to the "Classpath" exception as provided

 *

 * 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.

 *

 */

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <process.h>

/*

 * This is a primitive bootstrapping utility for executing Java CGI

 * programs, specifically Java RMI's CGI HTTP forwarding mechanism

 *

 * It executes the Java interpreter with options to define

 * properties corresponding to the environment variables set by the

 * CGI 1.0 specification and runs the target class.

 *

 * The following assumptions are made:

 *     - the Java interpreter can be located by the system

 *       PATH variable

 *     - for RMI 1.1 prebeta release, the target class can be located

 *       using the system CLASSPATH variable

 */

/* name of Java interpreter executable */

#define JAVA_NAME "java"

/* name of Java class to execute with interpreter */

#define CLASS_NAME "sun.rmi.transport.proxy.CGIHandler"

/* names of environment variables set in CGI 1.0 interface */

static char *var_names[] = {

    "AUTH_TYPE",

    "CONTENT_LENGTH",

    "CONTENT_TYPE",

    "GATEWAY_INTERFACE",

    "HTTP_ACCEPT",

    "PATH_INFO",

    "PATH_TRANSLATED",

    "QUERY_STRING",

    "REMOTE_ADDR",

    "REMOTE_HOST",

    "REMOTE_IDENT",

    "REMOTE_USER",

    "REQUEST_METHOD",

    "SCRIPT_NAME",

    "SERVER_NAME",

    "SERVER_PORT",

    "SERVER_PROTOCOL",

    "SERVER_SOFTWARE"

};

#define NUM_VARS (sizeof(var_names) / sizeof(var_names[0]))

/* file static functions */

static void server_error(char *);

/*

 * Program entry point: set up arguments and invoke Java interpreter.

 */

int

main(

    int     argc,

    char   *argv[]

)

{

    int     i;                  /* loop index variable */

    char  **args;               /* array to store arguments to interpreter */

    int     n = 0;              /* next index to fill in argument array */

    /* allocate space for argument list */

    args = (char **)            /* allocate space for: */

        malloc((1               /* executable name */

                + NUM_VARS      /* property definition for each variable */

                + 1             /* class name */

                + 1)            /* terminating NULL */

                * sizeof(*args));

    if (args == NULL) {

        server_error("memory allocation failure");

        return 1;

    }

    /* first argument: name of java interpreter */

    args[n ++] = JAVA_NAME;

    /* next arguments: define CGI variables as properties to Java VM */

    for (i = 0; i < NUM_VARS; ++ i) {

        char *name = var_names[i];      /* name of variable */

        char *value;                    /* value of variable */

        char *buffer;                   /* buffer to store argument string */

        value = getenv(name);

        if (value == NULL)              /* if variable undefined, */

            value = "";                 /* use empty string */

        buffer = (char *)               /* allocate space for: */

            malloc((2                   /* "-D" */

                    + strlen(name)      /* variable name */

                    + 2                 /* "=\"" */

                    + strlen(value)     /* variable value */

                    + 2)                /* "\"" and terminating '\0' */

                    * sizeof(*buffer));

        if (buffer == NULL) {

            server_error("memory allocation failure");

            return 1;

        }

        /* construct property definition parameter */

        sprintf(buffer, "-D%s=\"%s\"", name, value);

        args[n ++] = buffer;            /* add to argument list */

    }

    /* last argument: name of class to execute */

    args[n ++] = CLASS_NAME;

    args[n ++] = NULL;          /* terminate argument list */

    _execvp(JAVA_NAME, args);   /* execute java interpreter */

    /* if exec call returns, there was an error */

    server_error("interpreter execution failure");

    return 1;

}

/*

 * Return primitive error message to server because of some failure in

 * this program.  (This could be embellished to an HTML formatted error

 * message.)

 */

static void

server_error(

    char  *message

)

{

    /*

     * NOTE: CGI 1.0 spec uses "\n" (unlike "\r\n"

     * for HTTP 1.0) for line termination

     */

    printf("Status: 500 Server Error: %s\n", message);

    printf("Content-type: text/plain\n");

    printf("\n");

    printf("%s", message);

}