OpenVMS Source Code Demos
EBCDIC-ASCII-DEMO.C
//==============================================================================
// title : EBCDIC-ASCII.c
// author : Neil Rieck (email: n.rieck@bell.net)
// : https://neilrieck.net/
// 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
#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"); //
}