1: /*
   2:  * Copyright (c) 1982, 1986 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  *
   6:  *	@(#)kern_subr.c	7.1 (Berkeley) 6/5/86
   7:  */
   8: 
   9: #include "param.h"
  10: #include "systm.h"
  11: #include "dir.h"
  12: #include "user.h"
  13: #include "uio.h"
  14: 
  15: uiomove(cp, n, rw, uio)
  16:     register caddr_t cp;
  17:     register int n;
  18:     enum uio_rw rw;
  19:     register struct uio *uio;
  20: {
  21:     register struct iovec *iov;
  22:     u_int cnt;
  23:     int error = 0;
  24: 
  25:     while (n > 0 && uio->uio_resid) {
  26:         iov = uio->uio_iov;
  27:         cnt = iov->iov_len;
  28:         if (cnt == 0) {
  29:             uio->uio_iov++;
  30:             uio->uio_iovcnt--;
  31:             continue;
  32:         }
  33:         if (cnt > n)
  34:             cnt = n;
  35:         switch (uio->uio_segflg) {
  36: 
  37:         case UIO_USERSPACE:
  38:         case UIO_USERISPACE:
  39:             if (rw == UIO_READ)
  40:                 error = copyout(cp, iov->iov_base, cnt);
  41:             else
  42:                 error = copyin(iov->iov_base, cp, cnt);
  43:             if (error)
  44:                 return (error);
  45:             break;
  46: 
  47:         case UIO_SYSSPACE:
  48:             if (rw == UIO_READ)
  49:                 bcopy((caddr_t)cp, iov->iov_base, cnt);
  50:             else
  51:                 bcopy(iov->iov_base, (caddr_t)cp, cnt);
  52:             break;
  53:         }
  54:         iov->iov_base += cnt;
  55:         iov->iov_len -= cnt;
  56:         uio->uio_resid -= cnt;
  57:         uio->uio_offset += cnt;
  58:         cp += cnt;
  59:         n -= cnt;
  60:     }
  61:     return (error);
  62: }
  63: 
  64: /*
  65:  * Give next character to user as result of read.
  66:  */
  67: ureadc(c, uio)
  68:     register int c;
  69:     register struct uio *uio;
  70: {
  71:     register struct iovec *iov;
  72: 
  73: again:
  74:     if (uio->uio_iovcnt == 0)
  75:         panic("ureadc");
  76:     iov = uio->uio_iov;
  77:     if (iov->iov_len <= 0 || uio->uio_resid <= 0) {
  78:         uio->uio_iovcnt--;
  79:         uio->uio_iov++;
  80:         goto again;
  81:     }
  82:     switch (uio->uio_segflg) {
  83: 
  84:     case UIO_USERSPACE:
  85:         if (subyte(iov->iov_base, c) < 0)
  86:             return (EFAULT);
  87:         break;
  88: 
  89:     case UIO_SYSSPACE:
  90:         *iov->iov_base = c;
  91:         break;
  92: 
  93:     case UIO_USERISPACE:
  94:         if (suibyte(iov->iov_base, c) < 0)
  95:             return (EFAULT);
  96:         break;
  97:     }
  98:     iov->iov_base++;
  99:     iov->iov_len--;
 100:     uio->uio_resid--;
 101:     uio->uio_offset++;
 102:     return (0);
 103: }
 104: 
 105: /*
 106:  * Get next character written in by user from uio.
 107:  */
 108: uwritec(uio)
 109:     struct uio *uio;
 110: {
 111:     register struct iovec *iov;
 112:     register int c;
 113: 
 114:     if (uio->uio_resid <= 0)
 115:         return (-1);
 116: again:
 117:     if (uio->uio_iovcnt <= 0)
 118:         panic("uwritec");
 119:     iov = uio->uio_iov;
 120:     if (iov->iov_len == 0) {
 121:         uio->uio_iov++;
 122:         if (--uio->uio_iovcnt == 0)
 123:             return (-1);
 124:         goto again;
 125:     }
 126:     switch (uio->uio_segflg) {
 127: 
 128:     case UIO_USERSPACE:
 129:         c = fubyte(iov->iov_base);
 130:         break;
 131: 
 132:     case UIO_SYSSPACE:
 133:         c = *iov->iov_base & 0377;
 134:         break;
 135: 
 136:     case UIO_USERISPACE:
 137:         c = fuibyte(iov->iov_base);
 138:         break;
 139:     }
 140:     if (c < 0)
 141:         return (-1);
 142:     iov->iov_base++;
 143:     iov->iov_len--;
 144:     uio->uio_resid--;
 145:     uio->uio_offset++;
 146:     return (c & 0377);
 147: }
Last modified: 1986-06-05
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