RISC DISC 2/RISC_DISC_2.iso/pd_share/program/language/as/source/c/uname

Text File | 1994-09-27 | 5.2 KB | 185 lines

/* uname.c (c) Copyright 1992 Niklas Röjemo */

#include <ctype.h>
#include <string.h>
#include <stdlib.h>

#include "kernel.h"


#define EXTRA(x) ((x)<<1)  /* Reserve double space */

char *special1(char const *dotpos, char const *end)
{
  int s = end - dotpos;
  if(s == 1)
    switch(*dotpos) {
      case 'c': return "c";
      case 'h': return "h";
      case 'p': return "p";
      case 'o': return "o";
      case 's': return "s";
      case 'm': return "m";
      case 't': return "t";
      case 'M': return "mc";
    }
  else {
    if(!strncmp(dotpos,"mc",s)) return "mc";
  }
  return 0;
}

char *special2(char const *dotpos, char const *end)
{
  int s = end - dotpos;
  if(s == 1)
    switch(*dotpos) {
      case 'l': return "l";
      case 'y': return "y";
    }
  else {
    if(!strncmp(dotpos,"tt",s)) return "tt";
  }
  return 0;
}


static int  sizeName;   /* Length of buffer */
static char *newName;   /* Name buffer */

char *uname(const char *name, int PrefixDir)
{
  char const *src;
  char *dst;
  char const *dotpos,*end,*pre;
  int  c;

  if (!name) return("");                        /* What no filename ! */

  if (EXTRA(c = strlen(name)) > sizeName) {     /* Reserve space */
    if(sizeName)
      free(newName);
      sizeName = c+100;            /* Add 100 increases chance we don't need to allocate again */
    if((newName = malloc(sizeName))==0) {
      sizeName = 0;
      return 0;
    }
  }

  src = name;
  dst = newName;

  if ((c=*src)==0) {        /* name == "" */
    *dst++ = 0;
    return newName;
  }

  if(  c == '<'  || c ==':'               /* No sane unixfiles start with < or : */
    || (src[1] == '.' &&                  /* $. @. %. ^. &. is not a unixfile    */
       (c == '$' || c == '@' || c == '%' || c == '^' || c == '&')) ) {
    if(PrefixDir && c == '@' && getenv("Prefix$Dir")) {
      strcpy(newName,"<Prefix$Dir>");
      strcat(newName,name+1);
    } else
      strcpy(newName,name);
    return newName;
  }

  if (c == '/') {                   /* Probably a unixfile */
    if (strncmp (src, "/tmp/", 5) == 0) {   /* if file is going into /tmp, check for */
      char *tmpdir = getenv("UnixFS$/tmp"); /* UnixFS$/tmp, else put in <wimp$Scrapdir> */
      if (!tmpdir || *tmpdir == 0)
    tmpdir = "<Wimp$ScrapDir>";
      strcpy (dst, tmpdir);
      dst += strlen (tmpdir);
      src += 4;
    } else
      *dst++ = '$';             /* change / to $. The dot is set in the while loop below */
  } else {
    if(PrefixDir && getenv("Prefix$Dir")) {
      strcpy(newName,"<Prefix$Dir>");
      dst += strlen("<Prefix$Dir>");
    } else
      *dst++ = '@';                        /* insert current dir */
  }

  while (*src) {
    while (*src == '/')               /* change multiple / to . */
      src++;
    *dst++ = '.';

    if (src[0] == '.' && src[1] == '.' && (src[2] == '/' || !src[2])) {
      *dst++ = '^';                      /* change .. to ^ */
      src += 2;
      continue;
    }
    if (src[0] == '.' && (src[1] == '/' || !src[1])) {
      dst--;                             /* remove the previous . in newName */
      src++;                             /* and skip . in name */
      continue;
    }

    end = dotpos = src;                 /* locate end of this filename */
    while ((c = *end)!=0 && c != '/') {    /* and the position of the last dot in the name */
      if (c == '.')
        dotpos = end;
      end++;
    }
    if((pre = special2(src,end))!=0) {          /* This is a /-prefix  ! */
      if(dst>newName)
        dst[-1] = '/';
      while((*dst++=*pre++)!=0)
        ;
      dst--;
      src = end;
    } else {
      if (dotpos++ > src && dotpos < end) { /* We have a base.suffix */
        if((pre = special1(dotpos,end))!=0) {
          while((*dst++ = *pre++)!=0)        /* This is a special suffix */
            ;                                /* now prefix */
          dst[-1] = '.';
          dotpos --;                         /* point to dot */
          while(src<dotpos)                  /* Change all other dots into _ */
            if((*dst++ = *src++) == '.')     /* when copying */
              dst[-1] = '_';
          src = end;
        } else {                             /* is it a /prefix? */
          if((pre = special1(src,--dotpos))!=0) { /* But the prefix is special ! */
            while(src<end)                       /* Copy as is  */
              *dst++ = *src++;
          } else {
            while(src<dotpos)                  /* Change all dots except the last into _ */
              if((*dst++ = *src++) == '.')
                dst[-1] = '_';
            *dst++ = '/';
             src++;
            while(src<end)                     /* And now the suffix */
              *dst++ = *src++;
          }
        }
      } else {       /* No dot or .base or base. */
          while(src<end)                     /* Change all dots into _ */
            if((*dst++ = *src++) == '.')
              dst[-1] = '_';
      }
    }
  }
  *dst = 0;


  /* a quick and dirty way to ensure the directory exists */
  while (dst>newName && *dst != '.')
    dst--;
  if(*dst == '.') {
    _kernel_osfile_block block;
    *dst = '\0';
    block.start = 0;
    (void)_kernel_osfile(8,newName, &block);
    *dst = '.';
  }


  return newName;
}