/*****************************************************************************/
/*
                                   util.c

Module name says it all.



COPYRIGHT
---------
Copyright (C) 2017-2019 Mark G.Daniel
This program comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to redistribute it under the
conditions of the GNU GENERAL PUBLIC LICENSE, version 3, or any later version.
http://www.gnu.org/licenses/gpl.txt



VERSION HISTORY
---------------
20-MAR-2019  MGD  UtilSetPrn() return NULL on set process name failure
06-JAN-2019  MGD  minor changes at v2.0
23-APR-2017  MGD  initial
*/
/*****************************************************************************/

#include <ctype.h>
#include <errno.h>
#include <stat.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <types.h>
#include <unistd.h>
#include <unixlib.h>

#include <descrip.h>
#include <jpidef.h>
#include <lnmdef.h>
#include <prvdef.h>
#include <ssdef.h>
#include <starlet.h>

#include "asprintf.h"
#include "certman.h"
#include "util.h"
#include "acme-client/wcme_config.h"

#define FI_LI "UTIL", __LINE__

#ifdef WCME_DBG_VMS
int doddbg(char*, ...);
#endif

/*****************************************************************************/
/*
Disable all privleges except NETMBX and TMPMBX in the calling process.
*/

void UtilMereMortal ()

{
   static ulong  GroundMask [2] = { ~(PRV$M_NETMBX | PRV$M_TMPMBX), -1 };

   int  status;

   /*********/
   /* begin */
   /*********/

   status = sys$setprv (0, &GroundMask, 0, 0);
   if (!(status & 1)) EXIT_FI_LI (status);
}

/*****************************************************************************/
/*
Enable SYSPRV in the calling process.
*/

void UtilSysPrv ()

{
   static ulong  SysPrvMask [2] = { PRV$M_SYSPRV, 0 };

   int  status;
   ulong  PrevPrvMask [2] = { 0, 0 };

   /*********/
   /* begin */
   /*********/

   status = sys$setprv (1, &SysPrvMask, 0, &PrevPrvMask);
   if ((status & 1) == 0) EXIT_FI_LI (status);
   /* if already enabled then consider that a programming error */
   if (PrevPrvMask[0] & PRV$M_SYSPRV) EXIT_FI_LI (SS$_BUGCHECK);
}

/*****************************************************************************/
/*
Enable IMPERSONATE in the calling process.
*/

void UtilImpersonate ()

{
   static ulong  ImpersonateMask [2] = { PRV$M_IMPERSONATE, 0 };

   int  status;
   ulong  PrevPrvMask [2] = { 0, 0 };

   /*********/
   /* begin */
   /*********/

   status = sys$setprv (1, &ImpersonateMask, 0, &PrevPrvMask);
   if ((status & 1) == 0) EXIT_FI_LI (status);
   /* if already enabled then consider that a programming error */
   if (PrevPrvMask[0] & PRV$M_IMPERSONATE) EXIT_FI_LI (SS$_BUGCHECK);
}

/*****************************************************************************/
/*
 * Wrap around asprintf(3), which sometimes nullifies the input values,
 * sometimes not, but always returns <0 on error.
 * Returns NULL on failure or the pointer on success.
 */
char *
doasprintf(char *fmt, ...)
{
        int      c;
        char    *cp;
        va_list  ap;

        va_start(ap, fmt);
        c = vasprintf(&cp, fmt, ap);
        va_end(ap);
        return(c < 0 ? NULL : cp);
}

/*****************************************************************************/
/*
Return a pointer to an equivalent VMS name.
Calling code must cast return value using (char*) and type as -1.
Also acts as its own callback routine.
*/

int UtilVmsName
(
char *name,
int type
)
{
   static char  *vname;

   /*********/
   /* begin */
   /*********/

   if (type == -1) 
   {
      if (decc$to_vms (name, UtilVmsName, 0, 0) != 1)
      {
         if (vname) free (vname);
         vname = NULL;
      }
      return ((int)vname);
   }

   if (vname) free (vname);

   if (type == DECC$K_DIRECTORY ||
       type == DECC$K_FOREIGN) 
   {
      vname = NULL;
      return (0);
   }

   vname = strdup(name);
   return (1); 
}

/*****************************************************************************/
/*
Allowed to use the application?
*/

int UtilHaveSysPrv ()
{
   static ulong  SysPrvMask[2] = { PRV$M_SYSPRV, 0 };

   return (UtilHavePriv(SysPrvMask));
}

/*****************************************************************************/
/*
Check privilege mask.  Return true or false.
*/

int UtilHavePriv (ulong *PrivMask)
{
   static ulong  JpiImagPriv [2],
                 JpiProcPriv [2];

   static struct {
      short int  buf_len;
      short int  item;
      void  *buf_addr;
      ushort  *ret_len;
   } JpiItemList[] = 
   {
       { sizeof(JpiImagPriv), JPI$_IMAGPRIV, &JpiImagPriv, 0 },
       { sizeof(JpiProcPriv), JPI$_PROCPRIV, &JpiProcPriv, 0 },
       {0,0,0,0}
   };

   int  status;

   /*********/
   /* begin */
   /*********/

   status = sys$getjpiw (0, 0, 0, &JpiItemList, 0, 0, 0);

   if ((status & 1) == 0) exit(status);

   return ((((JpiImagPriv[0] & PrivMask[0]) == PrivMask[0]) &&
            ((JpiImagPriv[1] & PrivMask[1]) == PrivMask[1])) ||
           (((JpiProcPriv[0] & PrivMask[0]) == PrivMask[0]) &&
            ((JpiProcPriv[1] & PrivMask[1]) == PrivMask[1])));
}

/*****************************************************************************/
/*
Return true if interactive process.
*/

int UtilInteractive ()
{
   static int  status;
   static ulong  JpiMode;
   static struct {
      short int  buf_len;
      short int  item;
      void  *buf_addr;
      ushort  *ret_len;
   } JpiItemList[] = 
   {
       { sizeof(JpiMode), JPI$_MODE, &JpiMode, 0 },
       {0,0,0,0}
   };

   /*********/
   /* begin */
   /*********/

   if (!status)
   {
      status = sys$getjpiw (0, 0, 0, &JpiItemList, 0, 0, 0);
      if (!(status & 1)) exit (status);
   }
   return (JpiMode == JPI$K_INTERACTIVE);
}

/*****************************************************************************/
/*
ODS-2-ify (39.39) the supplied file name.
If a file type is supplied a 39+ name is truncated.
If not it is continued as the type up to 39 length.
Expects file specification to be in U*x format.
Returns allocated string which must be freed by caller.
*/

char* UtilOds2FileName
(
char* fddir,
char* fname,
char* ftype
)
{
   char  *aptr, *cptr, *sptr, *zptr, *name, *type;
   char  buf [256];

   /*********/
   /* begin */
   /*********/

   zptr = (sptr = buf) + sizeof(buf)-1;
   if (fddir)
   {
      for (cptr = fddir; *cptr && sptr < zptr; *sptr++ = *cptr++);
      if (*(sptr-1) != '/' && sptr < zptr) *sptr++ = '/';
   }
   cptr = fname;
   name = sptr;
   while (*cptr && sptr < zptr && sptr - name < 39)
   {
      if (isalnum(*cptr) || *cptr == '-')
         *sptr++ = *cptr;
      else
      if (*cptr == '.' && !ftype)
      {
         for (aptr = cptr + 1; *aptr && *aptr != '.'; aptr++);
         if (*aptr == '.')
            *sptr++ = '_';
         else
            *sptr++ = '.';
      }
      else
         *sptr++ = '_';
      cptr++;
   }
   if (cptr = ftype)
   {
      if (*cptr == '.') cptr++;
      if (sptr < zptr) *sptr++ = '.';
      type = sptr;
      while (*cptr && sptr < zptr && sptr - type < 39)
      {
         if (isalnum(*cptr) || *cptr == '-')
            *sptr++ = *cptr;
         else
            *sptr++ = '_';
         cptr++;
      }
   }
   if (sptr >= zptr) exit (SS$_RESULTOVF);
   *sptr = '\0';

#ifdef WCME_DBG_VMS
   doddbg("ODS-2: %s", buf);
#endif

   return (strdup(buf));
}

/*****************************************************************************/
/*
If |name| not NULL sets the process name.  Return NULL if this fails.
Always returns a pointer to the significant portion of the process name.
*/

char* UtilSetPrn (char *name)

{
   static char  *NamePtr = "";
   static char  prcnam [16];

   char  *cptr, *sptr, *zptr;
   $DESCRIPTOR (NameDsc, (char*)prcnam);

   /*********/
   /* begin */
   /*********/

   if (!name) return (NamePtr);

   zptr = (sptr = prcnam) + sizeof(prcnam)-1;
   for (cptr = "WCME-"; *cptr && sptr < zptr; *sptr++ = *cptr++);
   NamePtr = sptr;
   for (cptr = name; *cptr && sptr < zptr; *sptr++ = *cptr++);
   *sptr = '\0';
   NameDsc.dsc$w_length = sptr - prcnam;
   if (*name)
      if (!(sys$setprn (&NameDsc) & 1))
         return (NULL);
   return (NamePtr);
}

/*****************************************************************************/
/*
Divine our image name.
*/

char* UtilImageName ()

{
   static char  JpiImagName [256];
   static struct
   {
      ushort  buf_len;
      ushort  item;
      uchar   *buf_addr;
      ushort  *short_ret_len;
   } JpiItems [] =
   {
      { sizeof(JpiImagName), JPI$_IMAGNAME, (uchar*)&JpiImagName, 0 },
      { 0,0,0,0 }
   };

   int  status;
   char  *cptr;

   /*********/
   /* begin */
   /*********/

   if (JpiImagName[0]) return (JpiImagName);

   status = sys$getjpiw (0, 0, 0, &JpiItems, 0, 0, 0);
   if ((status & 1) == 0) exit(status);

   /* when fork()ing ensure we're not using a specific version */
   for (cptr = JpiImagName; *cptr && *cptr != ';'; cptr++);
   if (*cptr == ';') *cptr = '\0';

   return (JpiImagName);
}

/*****************************************************************************/
/*
What's my user name?
*/

char* UtilUserName ()

{
   static char  JpiUserName [12+1];
   static struct
   {
      ushort  buf_len;
      ushort  item;
      uchar   *buf_addr;
      ushort  *short_ret_len;
   } JpiItems [] =
   {
      { sizeof(JpiUserName)-1, JPI$_USERNAME, (uchar*)&JpiUserName, 0 },
      { 0,0,0,0 }
   };

   int  status;
   char  *cptr;

   /*********/
   /* begin */
   /*********/

   if (JpiUserName[0]) return (JpiUserName);

   status = sys$getjpiw (0, 0, 0, &JpiItems, 0, 0, 0);
   if ((status & 1) == 0) exit(status);

   for (cptr = JpiUserName; *cptr && *cptr != ' '; cptr++);
   *cptr = '\0';

   return (JpiUserName);
}

/*****************************************************************************/
/*
Return a pointer to a static buffer containing the string equivalent of the
supplied VMS status value.
*/

char* UtilGetMsg (int status)
{
   static char  buf [256];

   unsigned short  slen;
   $DESCRIPTOR (bufDsc, buf);

   /*********/
   /* begin */
   /*********/

   sys$getmsg (status, &slen, &bufDsc, 1, 0);
   buf[slen] = '\0';
   buf[0] = toupper(buf[0]);
   return (buf);
}

/*****************************************************************************/
/*
Create a detached process executing under the optional username, the supplied
command procedure, with output to the optional file name.  Return a VMS status
value.
*/

int UtilCrePrcDetach
(
char *UserName,
char *SysCommand,
char *SysOutput,
char *ProcessName,
ulong *pidptr
)
{
#define ISS$C_ID_NATURAL 1
#define PRC$M_DETACH 0x200

   static ulong  CrePrcFlags = PRC$M_DETACH;
   static ulong  PersonaFlags = 0;
   static $DESCRIPTOR (LoginOutDsc, "SYS$SYSTEM:LOGINOUT.EXE");
   static $DESCRIPTOR (SysCommandDsc, "");
   static $DESCRIPTOR (SysOutputDsc, "");
   static $DESCRIPTOR (PrcNamDsc, "");
   static $DESCRIPTOR (UserNameDsc, "");

   int  handle, status;
   ulong  pid;

   /*********/
   /* begin */
   /*********/

   if (!SysCommand || !SysCommand[0]) return (SS$_ABORT);

   SysCommandDsc.dsc$a_pointer = SysCommand;
   SysCommandDsc.dsc$w_length = strlen(SysCommand);

   if (!SysOutput || !SysOutput[0]) SysOutput = "NL:";
   SysOutputDsc.dsc$a_pointer = SysOutput;
   SysOutputDsc.dsc$w_length = strlen(SysOutput);

   if (ProcessName)
   {
      if (ProcessName[0])
      {
         PrcNamDsc.dsc$a_pointer = ProcessName;
         PrcNamDsc.dsc$w_length = strlen(ProcessName);
      }
      else
         ProcessName = NULL;
   }

   UtilSysPrv();

   if (UserName && UserName[0])
   {
      UserNameDsc.dsc$a_pointer = UserName;
      UserNameDsc.dsc$w_length = strlen(UserName);

      UtilImpersonate();

      status = sys$persona_create (&handle, &UserNameDsc, PersonaFlags, 0, 0);
      if (!(status & 1)) return (status);

      status = sys$persona_assume (&handle, 0, 0, 0);
      if (!(status & 1)) return (status);
   }

   status = sys$creprc (pidptr,
                        &LoginOutDsc,
                        &SysCommandDsc,
                        &SysOutputDsc,
                        &SysOutputDsc,
                        0, 0,
                        ProcessName ? &PrcNamDsc : 0,
                        0, 0, 0,
                        CrePrcFlags,
                        0, 0);

   UtilMereMortal();

   if (UserName && UserName[0])
   {
      handle = ISS$C_ID_NATURAL;
      sys$persona_assume (&handle, 0, 0, 0);
   }

   /* the sys$creprc() status */
   return (status);
}

/*****************************************************************************/
/*
Translate a logical name using LNM$FILE_DEV by default or the specified name
table.  Returns a pointer to the value string, or NULL if the name does not
exist.  'IndexValue' should be zero for a 'flat' logical name, or 0..127 for
interative translations.  Returns pointer to non-reentrant static buffer which
must be strdup()ed if retained.
*/

char* UtilTrnLnm
(
char *LogName,
char *LogTable,
int IndexValue
)
{
   static ushort  ValueLength;
   static ulong  LnmAttributes,
                 LnmIndex;
   static char  LogValue [256];
   static $DESCRIPTOR (LogNameDsc, "");
   static $DESCRIPTOR (LogTableDsc, "");
   static struct {
      short int  buf_len;
      short int  item;
      void  *buf_addr;
      ushort  *ret_len;
   } LnmItems [] =
   {
      { sizeof(LnmIndex), LNM$_INDEX, &LnmIndex, 0 },
      { sizeof(LnmAttributes), LNM$_ATTRIBUTES, &LnmAttributes, 0 },
      { sizeof(LogValue), LNM$_STRING, LogValue, &ValueLength },
      { 0,0,0,0 }
   };

   int  status;

   /*********/
   /* begin */
   /*********/

   LnmIndex = IndexValue;

   if (LogTable)
   {
      LogTableDsc.dsc$a_pointer = LogTable;
      LogTableDsc.dsc$w_length = strlen(LogTable);
   }
   else
   {
      LogTableDsc.dsc$a_pointer = "LNM$FILE_DEV";
      LogTableDsc.dsc$w_length = sizeof("LNM$FILE_DEV")-1;
   }

   LogNameDsc.dsc$a_pointer = LogName;
   LogNameDsc.dsc$w_length = strlen(LogName);

   status = sys$trnlnm (0, &LogTableDsc, &LogNameDsc, 0, &LnmItems);
   if (!(status & 1) || !(LnmAttributes & LNM$M_EXISTS))
   {
      if (LogValue) LogValue[0] = '\0';
      return (NULL);
   }

   LogValue[ValueLength] = '\0';
   return (LogValue);
}

/*****************************************************************************/