ckufio.c

操作系统源代码

/*  Z C H D I R  --  Change directory  */

zchdir(dirnam) char *dirnam; {
    char *hd;
    if (*dirnam == '\0') hd = getenv("HOME");
    else hd = dirnam;
    return((chdir(hd) == 0) ? 1 : 0);
}


/*  Z H O M E  --  Return pointer to user's home directory  */

char *
zhome() {
    return(getenv("HOME"));
}

/*  Z G T D I R  --  Return pointer to user's current directory  */

char *
zgtdir() {

#ifdef MAXPATHLEN
#define CWDBL MAXPATHLEN
#else
#define CWDBL 100
#endif

#ifdef UXIII
    char cwdbuf[CWDBL+1];
    char *buf;
    char *getcwd();
    buf = cwdbuf;
    return(getcwd(buf,CWDBL));
#else
#ifdef BSD4
    char cwdbuf[CWDBL+1];
    char *buf;
    char *getwd();
    buf = cwdbuf;
    return(getwd(buf));
#else
    return("(directory unknown)");
#endif
#endif
}

/*  Z X C M D -- Run a system command so its output can be read like a file */

zxcmd(comand) char *comand; {
    int pipes[2];
    if (pipe(pipes) != 0) {
	debug(F100,"zxcmd pipe failure","",0);
	return(0);			/* can't make pipe, fail */
    }
#ifdef aegis
    if ((pid = vfork()) == 0) {		/* child */
#else
    if ((pid = fork()) == 0) {		/* child */
#endif


/*#if BSD4*/		/* Code from Dave Tweten@AMES-NAS */
			/* readapted to use getpwuid to find login shell */
			/*   -- H. Fischer */
	char *shpath, *shname, *shptr;	/* to find desired shell */
#ifndef aegis
	struct passwd *p;
	extern struct passwd * getpwuid();
	extern int getuid();
	char *defShel = "/bin/sh";	/* default shell */
#endif

	close(pipes[0]);		/* close input side of pipe */
	close(0);			/* close stdin */
	if (open("/dev/null",0) < 0) return(0);	/* replace input by null */

#ifndef UXIII
	dup2(pipes[1],1);		/* replace stdout & stderr */
	dup2(pipes[1],2);		/* by the pipe */
#else
	close(1);			/* simulate dup2 */
	if (dup(pipes[1]) != 1 )
	    conol("trouble duping stdout in routine zxcmd\n");
	close(2);			/* simulate dup2 */
	if (dup(pipes[1]) != 2 )
	    conol("trouble duping stderr in routine zxcmd\n");
#endif

	close(pipes[1]);		/* get rid of this copy of the pipe */

#ifdef aegis
	if ((shpath = getenv("SERVERSHELL")) == NULL) shpath = "/bin/sh";
#else

/**** 	shptr = shname = shpath = getenv("SHELL");  /* What shell? */
	p = getpwuid( getuid() );	/* get login data */
	if ( p == (struct passwd *) NULL || !*(p->pw_shell) ) shpath = defShel;
	  else shpath = p->pw_shell;
#endif
	shptr = shname = shpath;
	while (*shptr != '\0') if (*shptr++ == '/') shname = shptr;
	debug(F100,"zxcmd...","",0);
	debug(F110,shpath,shname,0);

/* Remove the following uid calls if they cause trouble... */
#ifdef BSD4
	setegid(getgid());		/* Override 4.3BSD csh */
	seteuid(getuid());		/*  security checks */
#endif /* bsd4 */

	execl(shpath,shname,"-c",comand,(char *)NULL); /* Execute the cmd */
	exit(0);			/* just punt if it failed. */
    } else if (pid == -1) {
	debug(F100,"zxcmd fork failure","",0);
	return(0);
    }
    close(pipes[1]);			/* don't need the output side */
    fp[ZIFILE] = fdopen(pipes[0],"r");	/* open a stream for it */
    fp[ZSYSFN] = fp[ZIFILE];		/* Remember. */
    return(1);
}

/*  Z C L O S F  - wait for the child fork to terminate and close the pipe. */

zclosf() {
    int wstat;
    if (kill(pid,9) == 0) {
	debug(F101,"zclosf pid =","",pid);
        while ((wstat = wait((int *)0)) != pid && wstat != -1) ;
        pid = 0;
    }
    fclose(fp[ZIFILE]);
    fp[ZIFILE] = fp[ZSYSFN] = NULL;
    return(1);
}

/*  Z X P A N D  --  Expand a wildcard string into an array of strings  */
/*
  Returns the number of files that match fn1, with data structures set up
  so that first file (if any) will be returned by the next znext() call.
*/
zxpand(fn) char *fn; {
    fcount = fgen(fn,mtchs,MAXWLD);	/* Look up the file. */
    if (fcount > 0) {
	mtchptr = mtchs;		/* Save pointer for next. */
    }
    debug(F111,"zxpand",mtchs[0],fcount);
    return(fcount);
}


/*  Z N E X T  --  Get name of next file from list created by zxpand(). */
/*
 Returns >0 if there's another file, with its name copied into the arg string,
 or 0 if no more files in list.
*/
znext(fn) char *fn; {
    if (fcount-- > 0) strcpy(fn,*mtchptr++);
    else *fn = '\0';
    debug(F111,"znext",fn,fcount+1);
    return(fcount+1);
}


/*  Z N E W N  --  Make a new name for the given file  */

znewn(fn,s) char *fn, **s; {
#ifdef BSD4
    static char buf[256];
#else
    static char buf[100];
#endif
    char *bp, *xp;
    int len = 0, n = 0, d = 0, t, i, power = 1;
#ifdef MAXNAMLEN
    int max = MAXNAMLEN;
#else
    int max = 14;
#endif
    bp = buf;
    while (*fn) {			/* Copy name into buf */
	*bp++ = *fn++;
	len++;
    }
    if (len > max-2) { 			/* Don't let it get too long */
	bp = buf + max-2;
	len = max - 2;
    }
	
    for (i = 1; i < 4; i++) {		/* Try up to 999 times */
	power *= 10;
	*bp++ = '*';			/* Put a star on the end */
	*bp-- = '\0';
	
	n = zxpand(buf);		/* Expand the resulting wild name */
    
	while (n-- > 0) {		/* Find any existing name~d files */
	    xp = *mtchptr++;
	    xp += len;
	    if (*xp == '~') {
		t = atoi(xp+1);
		if (t > d) d = t;	/* Get maximum d */
	    }
	}
	if (d < power-1) {
	    sprintf(bp,"~%d",d+1);	/* Make name~(d+1) */
	    *s = buf;
	    return;
	}
	bp--; len--;
    }
/* If we ever get here, we'll overwrite the xxx~100 file... */
}

/* Directory Functions for Unix, written by Jeff Damens, CUCCA, 1984. */

/*
 * The path structure is used to represent the name to match.
 * Each slash-separated segment of the name is kept in one
 * such structure, and they are linked together, to make
 * traversing the name easier.
 */

struct path {
              char npart[MAXNAMLEN];	/* name part of path segment */
              struct path *fwd;		/* forward ptr */
            };

#ifdef PROVX1
#define SSPACE 500
#else
#ifdef BSD29
#define SSPACE 500
#else
#ifdef aegis
#define SSPACE 10000			/* size of string-generating buffer */
static char bslash;			/* backslash character if active */
#else
#define SSPACE 2000			/* size of string-generating buffer */
#endif
#endif
#endif
static char sspace[SSPACE];             /* buffer to generate names in */
static char *freeptr,**resptr;         	/* copies of caller's arguments */
static int remlen;                      /* remaining length in caller's array*/
static int numfnd;                      /* number of matches found */

/*
 * splitpath:
 *  takes a string and splits the slash-separated portions into
 *  a list of path structures.  Returns the head of the list.  The
 *  structures are allocated by malloc, so they must be freed.
 *  Splitpath is used internally by the filename generator.
 *
 * Input: A string.
 * Returns: A linked list of the slash-separated segments of the input.
 */

struct path *
splitpath(p)
char *p;
{
 struct path *head,*cur,*prv;
 int i;
 head = prv = NULL;
 if (*p == '/') p++;            /* skip leading slash */
 while (*p != '\0')
 {
   cur = (struct path *) malloc(sizeof (struct path));
   debug(F101,"splitpath malloc","",cur);
   if (cur == NULL) fatal("malloc fails in splitpath()");
   cur -> fwd = NULL;
   if (head == NULL) head = cur;
   else prv -> fwd = cur;       /* link into chain */
   prv = cur;
#ifdef aegis
   /* treat backslash as "../" */
   if (bslash && *p == bslash) {
     strcpy(cur->npart, "..");
     ++p;
   } else {
     for (i=0; i < MAXNAMLEN && *p && *p != '/' && *p != bslash; i++)
       cur -> npart[i] = *p++;
     cur -> npart[i] = '\0';      /* end this segment */
     if (i >= MAXNAMLEN) while (*p && *p != '/' && *p != bslash) p++;
   }
   if (*p == '/') p++;
#else
   for (i=0; i < MAXNAMLEN && *p != '/' && *p != '\0'; i++)
     cur -> npart[i] = *p++;
   cur -> npart[i] = '\0';      /* end this segment */
   if (i >= MAXNAMLEN) while (*p != '/' && *p != '\0') p++;
   if (*p == '/') p++;
#endif
 }
 return(head);
}

/*
 * fgen:
 *  This is the actual name generator.  It is passed a string,
 *  possibly containing wildcards, and an array of character pointers.
 *  It finds all the matching filenames and stores them into the array.
 *  The returned strings are allocated from a static buffer local to
 *  this module (so the caller doesn't have to worry about deallocating
 *  them); this means that successive calls to fgen will wipe out
 *  the results of previous calls.  This isn't a problem here
 *  because we process one wildcard string at a time.
 *
 * Input: a wildcard string, an array to write names to, the
 *        length of the array.
 * Returns: the number of matches.  The array is filled with filenames
 *          that matched the pattern.  If there wasn't enough room in the
 *	    array, -1 is returned.
 * By: Jeff Damens, CUCCA, 1984.
 */

fgen(pat,resarry,len)
char *pat,*resarry[];
int len;
{
 struct path *head;
 char scratch[100],*sptr;
#ifdef aegis
 char *getenv(), *index(), *namechars;
 int tilde = 0, bquote = 0;

 if ((namechars = getenv("NAMECHARS")) != NULL) {
  if (index(namechars, '~' ) != NULL) tilde  = '~';
  if (index(namechars, '\\') != NULL) bslash = '\\';
  if (index(namechars, '`' ) != NULL) bquote = '`';
 }
 else { tilde = '~'; bslash = '\\'; bquote = '`'; }

 sptr = scratch;
 /* copy "`node_data", etc. anchors */
 if (bquote && *pat == bquote)
  while (*pat && *pat != '/' && *pat != bslash)
   *sptr++ = *pat++;
 else if (tilde && *pat == tilde)
  *sptr++ = *pat++;
 while (*pat == '/')
  *sptr++ = *pat++;
 if (sptr == scratch)
 {
  strcpy(scratch,"./");
  sptr = scratch+2;
 }					/* init buffer correctly */
 head = splitpath(pat);
#else
 head = splitpath(pat);
 if (*pat == '/')
 {
  scratch[0] = '/';
  sptr = scratch+1;
 }
 else
 {
  strcpy(scratch,"./");
  sptr = scratch+2;
 }					/* init buffer correctly */
#endif
 numfnd = 0;                            /* none found yet */
 freeptr = sspace;			/* this is where matches are copied */
 resptr = resarry;			/* static copies of these so*/
 remlen = len;				/* recursive calls can alter them */
 traverse(head,scratch,sptr);		/* go walk the directory tree */
 for (; head != NULL; head = head -> fwd)
   free(head);				/* return the path segments */
 return(numfnd);			/* and return the number of matches */
}

/* traverse:
 *  Walks the directory tree looking for matches to its arguments.
 *  The algorithm is, briefly:
 *   If the current pattern segment contains no wildcards, that
 *   segment is added to what we already have.  If the name so far
 *   exists, we call ourselves recursively with the next segment
 *   in the pattern string; otherwise, we just return.
 *
 *   If the current pattern segment contains wildcards, we open the name
 *   we've accumulated so far (assuming it is really a directory), then read
 *   each filename in it, and, if it matches the wildcard pattern segment, add
 *   that filename to what we have so far and call ourselves recursively on the
 *   next segment.
 *
 *   Finally, when no more pattern segments remain, we add what's accumulated
 *   so far to the result array and increment the number of matches.
 *
 * Input: a pattern path list (as generated by splitpath), a string
 *	  pointer that points to what we've traversed so far (this
 *	  can be initialized to "/" to start the search at the root
 *	  directory, or to "./" to start the search at the current
 *	  directory), and a string pointer to the end of the string
 *	  in the previous argument.
 * Returns: nothing.
 */
traverse(pl,sofar,endcur)
struct path *pl;
char *sofar,*endcur;
{
#ifdef BSD42
 DIR *fd, *opendir();
 struct direct *dirbuf;
#else
#ifdef BSD29
 DIR *fd, *opendir();
 struct direct *dirbuf;
#else
 int fd;
 struct direct dir_entry;
 struct direct *dirbuf = &dir_entry;
#endif
#endif
 struct stat statbuf;
 if (pl == NULL)
 {
  *--endcur = '\0';                    /* end string, overwrite trailing / */
  addresult(sofar);
  return;
 }
 if (!iswild(pl -> npart))
 {
  strcpy(endcur,pl -> npart);
  endcur += strlen(pl -> npart);
  *endcur = '\0';                     	/* end current string */
  if (stat(sofar,&statbuf) == 0)	/* if current piece exists */
  {
      *endcur++ = '/';                  /* add slash to end */
      *endcur = '\0';			/* and end the string */
      traverse(pl -> fwd,sofar,endcur);
  }
  return;
 }
/* cont'd... */

/*...traverse, cont'd */

/* segment contains wildcards, have to search directory */
 *endcur = '\0';                        	/* end current string */
 if (stat(sofar,&statbuf) == -1) return;   	/* doesn't exist, forget it */
 if ((statbuf.st_mode & S_IFDIR) == 0) return;  /* not a directory, skip */
#ifdef BSD42			/* ==BSD4 */
 if ((fd = opendir(sofar)) == NULL) return;  	/* can't open, forget it */
 while (dirbuf = readdir(fd))
#else
#ifdef BSD29			/* ==BSD29 */
 if ((fd = opendir(sofar)) == NULL) return;  	/* can't open, forget it */
 while (dirbuf = readdir(fd))
#else

 if ((fd = open(sofar,O_RDONLY)) < 0) return;  	/* can't open, forget it */
 while ( read(fd,dirbuf,sizeof dir_entry) )
#endif
#endif
{
  strncpy(nambuf,dirbuf->d_name,MAXNAMLEN); /* Get a null terminated copy!!! */
  nambuf[MAXNAMLEN] = '\0';
  if (dirbuf->d_ino != 0 && match(pl -> npart,nambuf)) {
    char *eos;
    strcpy(endcur,nambuf);
    eos = endcur + strlen(nambuf);
    *eos = '/';                    /* end this segment */
    traverse(pl -> fwd,sofar,eos+1);
  }
}
#ifdef BSD42			/* ==BSD4 */
 closedir(fd);
#else
#ifdef BSD29
 closedir(fd);
#else
 close(fd);
#endif
#endif
}

/*
 * addresult:
 *  Adds a result string to the result array.  Increments the number
 *  of matches found, copies the found string into our string
 *  buffer, and puts a pointer to the buffer into the caller's result
 *  array.  Our free buffer pointer is updated.  If there is no
 *  more room in the caller's array, the number of matches is set to -1.
 * Input: a result string.
 * Returns: nothing.
 */

addresult(str)
char *str;
{
 int l;
 if (strncmp(str,"./",2) == 0) str += 2;
 if (--remlen < 0) {
  numfnd = -1;
  return;
 }
 l = strlen(str) + 1;			/* size this will take up */
 if ((freeptr + l) > &sspace[SSPACE-1]) {
    numfnd = -1;			/* do not record if not enough space */
    return;
  }
 strcpy(freeptr,str);
 *resptr++ = freeptr;
 freeptr += l;
 numfnd++;
}

iswild(str)
char *str;
{
 char c;
 while ((c = *str++) != '\0')
   if (c == '*' || c == '?') return(1);
 return(0);
}

/*
 * match:
 *  pattern matcher.  Takes a string and a pattern possibly containing
 *  the wildcard characters '*' and '?'.  Returns true if the pattern
 *  matches the string, false otherwise.
 * by: Jeff Damens, CUCCA
 *
 * Input: a string and a wildcard pattern.
 * Returns: 1 if match, 0 if no match.
 */

match(pattern,string) char *pattern,*string; {
    char *psave,*ssave;			/* back up pointers for failure */
    psave = ssave = NULL;
    while (1) {
	for (; *pattern == *string; pattern++,string++)  /* skip first */
	    if (*string == '\0') return(1);	/* end of strings, succeed */
	if (*string != '\0' && *pattern == '?') {
	    pattern++;			/* '?', let it match */
	    string++;
	} else if (*pattern == '*') {	/* '*' ... */
	    psave = ++pattern;		/* remember where we saw it */
	    ssave = string;		/* let it match 0 chars */
	} else if (ssave != NULL && *ssave != '\0') {	/* if not at end  */
  					/* ...have seen a star */
	    string = ++ssave;		/* skip 1 char from string */
	    pattern = psave;		/* and back up pattern */
	} else return(0);		/* otherwise just fail */
    }
}