This document describes a method for building version 3.11 of the Hercules IBM mainframe emulator on VMS.
Some of the less portable Hercules features are not implemented such as SCSI tape support, TUN/TAP based networking, FBA block device support and HDL device support. Hercules devices which are implemented using HDL only will not work. These features could probably be included given some porting effort, however there does not seem to be sufficient requirement for them at present to justify the effort required.
Compilation is done with the default (32 bit) pointer size as there are issues with the argv pointer size, arguments to setvbuf() and several problems with getopt() when compilation is attempted with 64 bit pointers. This suggests there are likely to be problems trying to configure Hercules with main storage or expanded storage in the gigabytes range, however, I have not explored this.
A hack is performed to get the softfloat package to compile with least effort. This means that binary floating point operations may not work correctly if more than one CPU is configured in Hercules on VMS.
This procedure has been developed and tested on OpenVMS Alpha V8.3 with HP C V7.1-015 and Multinet V5.2 Rev A. It should work on other comparable versions of VMS / C / Multinet / TCPIP Services on Alpha or Itanium without modifications or with minor tweaks. Let me know if you experience any problems and I will try to fix them.
You will need:
If you want to compile Hercules with BZIP2 and ZLIB support, the bzlib.h, zconf.h and zlib.h header files and libbz2.olb and libz.olb object libraries built from the source should also be placed in the [.vms] subdirectory. I am not going to go into the detail of building these packages here as there are too many variables involved. If you run into any difficulties with them, let me know and I will help sort them out. If BZIP2 and ZLIB support is not required, comment out or remove the 5 lines referencing ZLIB, LIBZ, BZLIB and BZIP2 in [.vms]config.h and the 2 lines referencing libz and libbz2 in hercules.opt.
Eight of the source files supplied with Hercules should be modified as described below.
It is necessary to modify hdl.h to fix a bug which causes a compilation error when compiling without HDL (which is the path of least resistance on VMS). It is necessary to modify hmacros.h to avoid very poor performance and DBG error messages on the Hercules console due to calling select() with a non-socket file descriptor. The other changes are not essential but recommended, otherwise different parts of Hercules may fail to work.
If panel.c is not modified, the control panel does not accept keyboard input and Hercules can only be controlled using it's web interface (which is tricky to configure correctly but can be done. Ask me for details if you want it.)
If cardrdr.c is not modified, card readers do not work. If hetlib.c is not modified, HET tapes do not work. If hscutl.c is not modified, 2703 communication adaptors may cause Hercules to hang.
If hostopts.h is not modified, there will be many warnings that default host options are being used but few consequences. The changes to hdlmain.c avoids 2 undefined symbols at link time due to lack of TUN/TAP support. However, there do not appear to be any ill effects if this issue is ignored.
cardrdr.c
Locate 'dev->fh = fdopen(dev->fd, "rb");'. Replace with these 17 lines:
#ifdef __VMS
dev->fh = fdopen(dev->fd, "r");
#else /* __VMS */
dev->fh = fdopen(dev->fd, "rb");
#endif /* __VMS */
if (dev->fh == NULL)
{
/* Something went wrong with fdopen */
logmsg (_("HHCRD020E Error calling fdopen on file %s: %s\n"),
dev->filename, strerror(errno));
/* Set unit check with equipment check */
dev->sense[0] = SENSE_EC;
*unitstat = CSW_CE | CSW_DE | CSW_UC;
return -1;
}
hdl.h
Locate 'typedef struct _HDLINS'. Move this 8 line structure up above the
line containing : '#if !defined(OPTION_DYNAMIC_LOAD)'
hdlmain.c
Locate 'HDL_DEVICE(CTCI, ctci_device_hndinfo );'
Comment out or remove this line.
Locate 'HDL_DEVICE(LCS, lcs_device_hndinfo );'
Comment out or remove this line.
hetlib.c:
Locate 'omode = "r+b";'. Replace with these 5 lines:
#ifdef __VMS
omode = "r+";
#else /* __VMS */
omode = "r+b";
#endif /* __VMS */
Locate 'omode = "rb";'. Replace with these 5 lines:
#ifdef __VMS
omode = "r";
#else /* __VMS */
omode = "rb";
#endif /* __VMS */
hmacros.h
Locate '#define close_pipe(f) closesocket(f)'.
After that line, insert these 5 lines:
#elif defined( __VMS )
#define create_pipe(a) socketpair(AF_INET,SOCK_STREAM,IPPROTO_IP,a)
#define read_pipe(f,b,n) recv(f,b,n,0)
#define write_pipe(f,b,n) send(f,b,(int)n,0)
#define close_pipe(f) close(f)
hostopts.h
Locate '/* Hard-coded OTHER (DEFAULT) host-specific features and options... */'
Above this, insert the following 30 lines
/*-------------------------------------------------------------------*/
/* VMS host-specific features and options... */
/*-------------------------------------------------------------------*/
#elif defined(__VMS) /* VMS options */
/* Similar to OTHER with minor differences */
#define DLL_IMPORT extern /* (a safe default) */
#define DLL_EXPORT
#undef TUNTAP_IFF_RUNNING_NEEDED /* (NO tuntap support) */
#undef OPTION_SCSI_TAPE /* (NO SCSI tape support) */
#undef OPTION_SCSI_ERASE_TAPE /* (NOT supported) */
#undef OPTION_SCSI_ERASE_GAP /* (NOT supported) */
#undef OPTION_FBA_BLKDEVICE /* (no FBA BLKDEVICE support)*/
#define MAX_DEVICE_THREADS 0 /* (0 == unlimited) */
#undef MIXEDCASE_FILENAMES_ARE_UNIQUE /* ("Foo" same as "fOo"!!) */
#define DEFAULT_HERCPRIO 0
#define DEFAULT_TOD_PRIO -20
#define DEFAULT_CPU_PRIO 15
#define DEFAULT_DEV_PRIO 8
#if defined( HAVE_FORK )
#define HOW_TO_IMPLEMENT_SH_COMMAND USE_FORK_API_FOR_SH_COMMAND
#else
#define HOW_TO_IMPLEMENT_SH_COMMAND USE_ANSI_SYSTEM_API_FOR_SH_COMMAND
#endif
#define SET_CONSOLE_CURSOR_SHAPE_METHOD CURSOR_SHAPE_NOT_SUPPORTED
#undef OPTION_EXTCURS /* Normal cursor handling */
hscutl.c
locate 'int flags = fcntl( sfd, F_GETFL );'. Above it, insert these 10 lines:
#ifdef __VMS
u_long non_blocking_option = !blocking_mode;
if ( ioctl( sfd, FIONBIO, &non_blocking_option) != -1 )
return 0;
return -1;
#else /* __VMS */
locate 'return fcntl( sfd, F_SETFL, flags );'. Below it, insert this line:
#endif /* __VMS */
panel.c
Locate '#define DISPLAY_INSTRUCTION_OPERANDS'. After it, insert these 3 lines:
#ifdef __VMS
#include <descrip.h>
#endif // __VMS
Locate '#ifndef _MSVC_'. Replace it with this line:
#if !defined( _MSVC_ ) && !defined( __VMS )
Locate '#endif // _MSVC_'. Replace it with these 6 lines:
#endif // !_MSVC_ && !__VMS
#ifdef __VMS
int efn, status, lib$signal(), lib$get_ef(), sys$assign(), vms_getch();
short channel;
$DESCRIPTOR(input, "SYS$COMMAND:");
#endif // __VMS
Locate '/* Notify logger_thread we're in control */'.
Above it insert these 13 lines:
#ifdef __VMS
/* Reserve an event flag for calling sys$qiow in vms_getch() */
status = lib$get_ef(&efn);
if (!(status & 1)) lib$signal(status);
/* Assign a channel to sys$command for vms_getch() */
status = sys$assign(&input, &channel, 0, 0);
if (!(status & 1)) lib$signal(status);
#endif // __VMS
Locate '#else // !defined( _MSVC_ )'. Replace it with these 16 lines:
#elif defined( __VMS )
/* Wait for keyboard input */
#define WAIT_FOR_KEYBOARD_INPUT_SLEEP_MILLISECS (20)
for (i=sysblk.panrate/WAIT_FOR_KEYBOARD_INPUT_SLEEP_MILLISECS;
i && !(kbbuf[0] = vms_getch(efn, channel)); i--)
usleep(WAIT_FOR_KEYBOARD_INPUT_SLEEP_MILLISECS * 1000);
ADJ_SCREEN_SIZE();
/* If keyboard input has [finally] arrived, then process it */
if ( kbbuf[0] )
{
kbbuf[kblen=1] = '\0';
translate_keystroke( kbbuf, &kblen );
#else // !defined( _MSVC_ ) && !defined( __VMS )
Locate '#endif // defined( _MSVC_ )'. Replace it with this line:
#endif // defined( _MSVC_ ) || defined( __VMS )
Locate '/* Process the command when the ENTER key is pressed */'.
Above it, insert these two lines:
/* Translate CR into LF for unix type processing */
if (kbbuf[i] == '\r') kbbuf[i] = '\n';
That's it. All source modifications are now done and compilation can begin.
Set default to the [.vms] subdirectory. Issue this command: @[-]compile vms Set default to the [.decnumber] subdirectory. Issue this command: @compiledecnumber Set default to the [.softfloat] subdirectory. Issue this command: @compilesoftfloat Set default to the main source directory. Issue this command: @compilehercules Expect three MAYLOSEDATA2 warnings when compiling cpu.c and another three when compiling sie.c. There may also be some informational messages. If all went well, all the hercules source should now be compiled. If so, issue this command: @linkhercules and HERCULES.EXE should be generated. This can be run with command line arguments by setting up a foreign command symbol or a simple RUN HERCULES will run it with no command line arguments and it will look for a configuration file called hercules.cnf in the current default directory.
If you also wish to build the Hercules support utilites such as dasdinit and hetinit, issue these commands:
@compileothers @linkothersNote that there may be a issue with dasdls.c which may prevent it from compiling because of a BADCONDIT error. If this happens, locate ': printf(runflgs' and change it to ': (void) printf(runflgs' before trying again. Other than that, there should be no warnings or other messages.
If you are building without LIBZ and BZIP2 support, comment out or remove the references to libz and libbz2 from cckd.opt, dasd.opt and het.opt before linking.
Please note that I have not tested all the support utilities for correct operation but if any problems are found, I am happy to look into them.
Mail _software_@_beyondthepale_._ie_ (without the underscores) for further information or help with any problems building or running Hercules on VMS.