2.11BSD#431 - /usr/src/new/notes/src/pagemove.c

   1: #include "parms.h"
   2: #include "structs.h"
   3: 
   4: #ifdef  RCSIDENT
   5: static char rcsid[] = "$Header: pagemove.c,v 1.7.0.2 85/05/20 09:55:01 notes Rel $";
   6: #endif	RCSIDENT
   7: 
   8: /*
   9:  *	pagemove(io,where,io2,where2,lockflag)
  10:  *
  11:  *	Take the text pointed to by the (io,where) pair and stuff
  12:  *	it into the (io2) notesfile. Return the address in
  13:  *	(where2).
  14:  *
  15:  *	Lock the io2 notesfile for the transfer if the lockflag
  16:  *	parameter is non-zero.
  17:  *
  18:  *	Ray Essick, March 1985
  19:  */
  20: 
  21: pagemove (io, where, io2, where2, lockflag)
  22: struct io_f *io;
  23: struct daddr_f *where;
  24: struct io_f *io2;
  25: struct daddr_f *where2;
  26: int     lockflag;
  27: {
  28:     char    buf[BUFSIZ];                /* for moving chunks */
  29:     register int    bufchars;               /* in buffer */
  30:     register long   moved;              /* actually moved */
  31:     register long   total;
  32:     register long   need;
  33:     struct daddr_f  nwhere;
  34: 
  35:     if (where -> addr == 0 || where -> textlen == 0)
  36:     {                           /* no text or empty */
  37:     where2 -> addr = 0;
  38:     where2 -> textlen = 0;
  39:     return;                     /* cheap move */
  40:     }
  41: 
  42:     if (lockflag)                   /* lock if wanted */
  43:     locknf (io2, TXTLOCK);
  44: 
  45:     /*
  46:      * position the input and output files.
  47:      * we have to grab the free pointer for the output file.
  48:      */
  49:     x (lseek (io -> fidtxt, where -> addr, 0) != where -> addr, "pagemove: old seek");
  50:     x (lseek (io2 -> fidtxt, 0L, 0) != 0, "pagemove: io2 seek 0");
  51:     x (read (io2 -> fidtxt, where2, sizeof *where) != sizeof *where, "pagemove: read free");
  52:     x (lseek (io2 -> fidtxt, where2 -> addr, 0) != where2 -> addr, "pagemove: new seek");
  53:     moved = 0;
  54:     total = where -> textlen;               /* total to move */
  55:     bufchars = 0;
  56:     where2 -> textlen = 0;              /* start empty */
  57: 
  58:     while (moved != total)              /* more text */
  59:     {
  60:     need = total - moved;               /* how much wanted? */
  61:     if (need >= BUFSIZ)
  62:         need = BUFSIZ;              /* only so many at once */
  63:     bufchars = read (io -> fidtxt, buf, ((int) need));/* read them */
  64:     x (bufchars != need, "pagemove: bad read from old");/* check */
  65:     x (write (io2 -> fidtxt, buf, bufchars) != bufchars, "pagemove: bad write to new");
  66:     moved += bufchars;              /* bump counts */
  67:     where2 -> textlen += bufchars;
  68:     }
  69:     x (where -> textlen != where2 -> textlen, "pagemove: moved wrong count");
  70:     /*
  71:      * we now have shoved the text into the second notesfile.
  72:      * We need to go back and update the free pointer.
  73:      * and then we can return...
  74:      */
  75:     nwhere.textlen = 0;
  76:     nwhere.addr = where2 -> addr + where2 -> textlen;
  77:     if (nwhere.addr & 1)                /* odd? */
  78:     nwhere.addr++;                  /* round up */
  79:     x (lseek (io2 -> fidtxt, 0L, 0) != 0, "pagemove: bad reseek");
  80:     x (write (io2 -> fidtxt, &nwhere, sizeof nwhere) != sizeof nwhere, "pagemove: bad write free pointer");
  81: 
  82:     if (lockflag)                   /* cleanup */
  83:     unlocknf (io2, TXTLOCK);
  84: }

Defined functions

Defined variables