OpenVMS Source-Code Demos

EBCDIC-ASCII-DEMO.C

//==============================================================================
// title   : EBCDIC-ASCII.c
// author  : Neil Rieck (email: n.rieck@sympatico.ca)
//         : http://www3.sympatico.ca/n.rieck/
// notes   : derived from a partial web source at URL:
//           http://www.room42.com/store/computer_center/code_tables.shtml
// ver who when       what
// --- --- ---------- ----------------------------------------------------------
// 100 NSR 2002.02.14 1. original effort
// 101 NSR 2006.03.07 1. code clean up for VMS demo
// 102 NSR 2012.07.24 1. added code to demo two vms library calls
//==============================================================================
//
//	general 'c' stuff
//
#include <stdio.h>			// standard i/o
#include <string.h>			// string support
//
//	vms specific stuff
//
#ifdef VMS				// VMS
#define __NEW_STARLET	1		// enable new (strict) starlet for OpenVMS Alpha 7.0 and later
					// http://h71000.www7.hp.com/doc/82final/5841/5841pro_059.html
#include <starlet>			// vms starlet library
#include <lib$routines>			// vms lib$ RTL library
#include <libdef>			// eg. LIB$_NORMAL
#include <ssdef>			// eg. SS$_NORMAL
#include <descrip>			// VMS descriptors
#endif					// VMS

void    ASCII_to_EBCDIC ( long, char *, char *);
void    EBCDIC_to_ASCII ( long, char *, char *);

    //
    //    ASCII to EBCDIC translation table
    //
    static char ASCII_translate_EBCDIC [ 256 ] =
    {
        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
        0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18,
        0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
        0x40, 0x5A, 0x7F, 0x7B, 0x5B, 0x6C, 0x50, 0x7D, 0x4D,
        0x5D, 0x5C, 0x4E, 0x6B, 0x60, 0x4B, 0x61,
        0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8,
        0xF9, 0x7A, 0x5E, 0x4C, 0x7E, 0x6E, 0x6F,
        0x7C, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8,
        0xC9, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6,
        0xD7, 0xD8, 0xD9, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7,
        0xE8, 0xE9, 0xAD, 0xE0, 0xBD, 0x5F, 0x6D,
        0x7D, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88,
        0x89, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96,
        0x97, 0x98, 0x99, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7,
        0xA8, 0xA9, 0xC0, 0x6A, 0xD0, 0xA1, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B,
        0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B, 0x4B } ;

    //
    //    EBCDIC to ASCII translation table
    //
    static char EBCDIC_translate_ASCII [ 256 ] =
    {
        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
        0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18,
        0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
        0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28,
        0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F,
        0x2E, 0x2E, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38,
        0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x2E, 0x3F,
        0x20, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E,
        0x2E, 0x2E, 0x2E, 0x3C, 0x28, 0x2B, 0x7C,
        0x26, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E,
        0x2E, 0x21, 0x24, 0x2A, 0x29, 0x3B, 0x5E,
        0x2D, 0x2F, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E,
        0x2E, 0x7C, 0x2C, 0x25, 0x5F, 0x3E, 0x3F,
        0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E,
        0x2E, 0x3A, 0x23, 0x40, 0x27, 0x3D, 0x22,
        0x2E, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
        0x69, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E,
        0x2E, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71,
        0x72, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E,
        0x2E, 0x7E, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
        0x7A, 0x2E, 0x2E, 0x2E, 0x5B, 0x2E, 0x2E,
        0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E,
        0x2E, 0x2E, 0x2E, 0x2E, 0x5D, 0x2E, 0x2E,
        0x7B, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
        0x49, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E,
        0x7D, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50, 0x51,
        0x52, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E,
        0x5C, 0x2E, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
        0x5A, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E,
        0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38,
        0x39, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E } ;

//
//      EBCDIC_to_ASCII (string conversion)
//
void    EBCDIC_to_ASCII ( long buf_length, char *buf_addr1, char *buf_addr2)
{   int i;
    unsigned char temp;
    for (i=0; i < buf_length; i++)
    {
        temp = (unsigned char) buf_addr1[i];
        buf_addr2[i] = EBCDIC_translate_ASCII[temp];
	buf_addr2[i+1] = '\0';				// <nul> terminate
    }
}

//
//      ASCII_to_EBCDIC (string conversion)
//
void    ASCII_to_EBCDIC ( long buf_length, char *buf_addr1, char *buf_addr2)
{   int i;
    unsigned char temp;
    for (i=0; i < buf_length; i++)
    {
        temp = (unsigned char) buf_addr1[i];
        buf_addr2[i] = ASCII_translate_EBCDIC[temp];
	buf_addr2[i+1] = '\0';				// <nul> terminate
    }
}

//==============================================================================
//	main
//==============================================================================
void  main ( void )
{
    char buffer0[255];
    char buffer1[255];
    char buffer2[255];
    int junk, rc;
    //
    printf("\nEBCDIC-ASCII.c\n");
    printf(  "==============\n");
    //
    //	initialize buffer 0
    //
    strcpy(buffer0, "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz");
    //--------------------------------------------------------------------------
    //	convert (the hard way)
    //--------------------------------------------------------------------------
    printf("Hardway Code\n");
    ASCII_to_EBCDIC ( sizeof(buffer0), buffer0, buffer1 ) ;
    EBCDIC_to_ASCII ( sizeof(buffer1), buffer1, buffer2 ) ;
    //
    printf("The next 4 lines should match\n");
    printf("original data: %s\n"  , &buffer0);
    printf("EBCDIC   data: %s\n"  , &buffer1);
    printf("ASCII    data: %s\n\n", &buffer2);
    //
#ifdef VMS							// only valid on VMS
    //--------------------------------------------------------------------------
    //	convert (the easy way)
    //
    //	note: these lib$ calls require VMS string descriptors
    //  (so this will only appear easier after string setup)
    //--------------------------------------------------------------------------
    //
    //  32-bit Descriptor Prototype (from a dump of sys$library:SYS$STARLET_C.tlb
    //  ---------------------------
    //  Each class of 32-bit descriptor consists of at least 2 longwords in
    //  the following format:
    //
    //       +-------+-------+---------------+
    //       | CLASS | DTYPE |    LENGTH     |  :Descriptor
    //       +-------+-------+---------------+
    //       |            POINTER            |
    //       +-------------------------------+
    //
    //       DSC$W_LENGTH   A one-word field specific to the descriptor
    //       <0,15:0>       class    //   typically a 16-bit (unsigned) length.
    //
    //       DSC$B_DTYPE    A one-byte atomic data type code
    //       <0,23:16>
    //
    //       DSC$B_CLASS    A one-byte descriptor class code
    //       <0,31:24>
    //
    //       DSC$A_POINTER  A longword pointing to the first byte of the
    //       <1,31:0>       data element described.
    //--------------------------------------------------------------------------
    //
    //	declare some static strings (vms will not be able to extend)
    //
    static struct dsc$descriptor str0 =
	{ 0, DSC$K_DTYPE_T, DSC$K_CLASS_S, NULL };
    static struct dsc$descriptor str1 =
	{ 0, DSC$K_DTYPE_T, DSC$K_CLASS_S, NULL };
    static struct dsc$descriptor str2 =
	{ 0, DSC$K_DTYPE_T, DSC$K_CLASS_S, NULL };
    //
    printf("Easyway Code (VMS Only)\n");			//
    str0.dsc$w_length  = strlen(buffer0);			// make sure we send the correct length
    str1.dsc$w_length  = str0.dsc$w_length;			//
    str2.dsc$w_length  = str0.dsc$w_length;			//
    str0.dsc$a_pointer = buffer0;				//
    str1.dsc$a_pointer = buffer1;				//
    str2.dsc$a_pointer = buffer2;				//
    (void)memset (buffer1, 0, sizeof (buffer1));		// zap just to prove asc-ebc works
    (void)memset (buffer2, 0, sizeof (buffer2));		// zap just to prove ebc-asc works
    //
    //	unlike other lib$ functions, lib$tra_asc_ebc returns SS$_NORMAL rather than LIB$_NORMAL
    //
    rc = lib$tra_asc_ebc(&str0, &str1);				// ascii->ebcdic
    if (rc!=SS$_NORMAL) {
	printf("-e-lib$tra_ebc_asc rc: %ld but was expecting %ld\n",rc,SS$_NORMAL);
    }
    //
    //	unlike other lib$ functions, lib$tra_ebc_asc returns SS$_NORMAL rather than LIB$_NORMAL
    //
    rc = lib$tra_ebc_asc(&str1, &str2);				// ebcdic->ascii
    if (rc!=SS$_NORMAL) {
	printf("-e-lib$tra_asc_ebc rc: %ld but was expecting %ld\n",rc,SS$_NORMAL);
    }
    //
    printf("The next 4 lines should match\n");
    printf("original data: %s\n"  , &buffer0);
    printf("EBCDIC   data: %s\n"  , &buffer1);
    printf("ASCII    data: %s\n\n", &buffer2);
    //
#endif								// VMS
    printf("Hit <enter> ... ");					//
    junk = getchar();						//
    printf("\nBye...\n");					//
}