main.c

This is a java virtual machine implement in c

/*0001*//*
/*0002./ * Copyright (c) 1998-2001 Sun Microsystems, Inc. All Rights Reserved.
/*0003./ *
/*0004./ * This software is the confidential and proprietary information of Sun
/*0005./ * Microsystems, Inc. ("Confidential Information").  You shall not
/*0006./ * disclose such Confidential Information and shall use it only in
/*0007./ * accordance with the terms of the license agreement you entered into
/*0008./ * with Sun.
/*0009./ *
/*0010./ * SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF THE
/*0011./ * SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
/*0012./ * IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
/*0013./ * PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR ANY DAMAGES
/*0014./ * SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING
/*0015./ * THIS SOFTWARE OR ITS DERIVATIVES.
/*0016./ *
/*0017./ */
/*0018*/
/*0019*//*=========================================================================
/*0020./ * KVM
/*0021./ *=========================================================================
/*0022./ * SYSTEM:    KVM
/*0023./ * SUBSYSTEM: Main program
/*0024./ * FILE:      main.c
/*0025./ * OVERVIEW:  Main program for command-line based environments
/*0026./ * AUTHOR:    Antero Taivalsaari, Sun Labs
/*0027./ *            Edited by Doug Simon 11/1998
/*0028./ *            JAM integration by Sheng Liang
/*0029./ *
/*0030./ * NOTE:      KVM does not have a portable main() function.  This is
/*0031./ *            because the VM may be used in very different kinds of 
/*0032./ *            target environments.  Some of the environments may provide
/*0033./ *            command line support, while many don't; some environments
/*0034./ *            may launch the VM from a GUI or a micro-browser, etc.
/*0035./ *
/*0036./ *            The portable VM startup and shutdown operations are defined
/*0037./ *            in file VmCommon/src/StartJVM.c. The main() function defined
/*0038./ *            in this file is applicable only to those target systems that
/*0039./ *            support VM startup from a command line.
/*0040./ *=======================================================================*/
/*0041*/
/*0042*//*=========================================================================
/*0043./ * Include files
/*0044./ *=======================================================================*/
/*0045*/
/*0046*/#include <global.h>
/*0047*/
/*0052*//*=========================================================================
/*0053./ * Functions
/*0054./ *=======================================================================*/
/*0055*/
/*0056*/void printHelpText() {
/*0057*/    fprintf(stdout, "Usage: kvm <-options> <classfile>\n");
/*0058*/    fprintf(stdout, "Options:\n");
/*0059*/    fprintf(stdout, "  -version\n");
/*0060*/    fprintf(stdout, "  -classpath <filepath>\n");
/*0061*/    fprintf(stdout, "  -heapsize <size> (e.g. 65536 or 128k or 1M)\n");
/*0077*/}
/*0078*/
/*0079*/#ifndef BUILD_VERSION
/*0080*/#define BUILD_VERSION "generic"
/*0081*/#endif
/*0082*/
/*0083*/int main (int argc, char* argv[]) {
/*0085*/
/*0084*/    int result;
/*0090*/    JamEnabled = FALSE;
/*0091*/    JamRepeat = FALSE;
/*0092*/    RequestedHeapSize = DEFAULTHEAPSIZE;
/*0093*/
/*0098*/    while (argc > 1) {    
/*0099*/        if (strcmp(argv[1], "-version") == 0) {
/*0100*/            fprintf(stdout, "Version: %s\n", BUILD_VERSION);
/*0101*/            exit(1);           
/*0102*/        } else if (strcmp(argv[1], "-help") == 0) {
/*0103*/            printHelpText();
/*0104*/            exit(0);
/*0121*/        } else if ((strcmp(argv[1], "-heapsize") == 0) && (argc > 2)) {
/*0122*/            char *endArg;
/*0123*/            long heapSize = strtol(argv[2], &endArg, 10);
/*0124*/            switch (*endArg) { 
/*0125*/                case '\0':            break;
/*0126*/                case 'k': case 'K':   heapSize <<= 10; break;
/*0127*/                case 'm': case 'M':   heapSize <<= 20; break;
/*0128*/                default:              printHelpText(); exit(1);
/*0129*/            }
/*0130*/
/*0131*/            /* In principle, KVM can run with just a few kilobytes */
/*0132*/            /* of heap space.  However, CLDC Spec says that the minimum */
/*0133*/            /* is 32 kilobytes.  The maximum heap size allowed by the */
/*0134*/            /* garbage collector is 64 megabytes.  In practice, the */
/*0135*/            /* collector is optimized only for small heaps, and is */
/*0136*/            /* likely to have long GC pauses with heaps larger than */
/*0137*/            /* a few megabytes */
/*0138*/            if (heapSize < 32 * 1024) { 
/*0139*/                fprintf(stderr, KVM_MSG_USES_32K_MINIMUM_MEMORY "\n");
/*0140*/                heapSize = 32 * 1024;
/*0141*/            }
/*0142*/            if (heapSize > 64 * 1024 * 1024) {
/*0143*/                fprintf(stderr, KVM_MSG_USES_64M_MAXIMUM_MEMORY "\n");
/*0144*/                heapSize = 64 * 1024 * 1024;
/*0145*/            }
/*0146*/
/*0147*/            /* Make sure the heap size is divisible by four */
/*0148*/            heapSize -= heapSize%CELL;
/*0149*/           
/*0150*/            argv+=2; argc -=2;
/*0151*/            RequestedHeapSize = heapSize;
/*0152*/        } else if ((strcmp(argv[1], "-classpath") == 0) && argc > 2) {
/*0157*/            UserClassPath = argv[2];
/*0158*/            argv+=2; argc -=2;
/*0197*/        } else {
/*0198*/            break; //\\