kernel/krtld/kobj_subr.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #include <sys/types.h>
  27 #include <sys/param.h>
  28 #include <sys/systm.h>
  29
  30 #include <sys/bootconf.h>
  31 #include <sys/kobj_impl.h>
  32 #include <sys/cmn_err.h>
  33
  34 /*
  35  * Standalone utility functions for use within krtld.
  36  * Many platforms implement optimized platmod versions of
  37  * utilities such as bcopy and any such are not yet available
  38  * until the kernel is more completely stitched together.
  39  * These standalones are referenced through vectors
  40  * kobj_bzero, etc.  Throughout krtld, the usual utility
  41  * is redefined to reference through the corresponding
  42  * vector so that krtld may simply refer to bzero etc.
  43  * as usual.  See kobj_impl.h.
  44  */
  45 extern void vprintf(const char *, va_list);
  46
  47 /*ARGSUSED*/
  48 static void
  49 vkprintf(void *op, const char *fmt, va_list adx)
  50 {
  51         vprintf(fmt, adx);
  52 }
  53
  54 static void
  55 kprintf(void *op, const char *fmt, ...)
  56 {
  57         va_list adx;
  58
  59         va_start(adx, fmt);
  60         vkprintf(op, fmt, adx);
  61         va_end(adx);
  62 }
  63
  64 static void
  65 stand_bzero(void *p_arg, size_t count)
  66 {
  67         char zero = 0;
  68         caddr_t p = p_arg;
  69
  70         while (count != 0)
  71                 *p++ = zero, count--;
  72 }
  73
  74 static void
  75 stand_bcopy(const void *src_arg, void *dest_arg, size_t count)
  76 {
  77         caddr_t src = (caddr_t)src_arg;
  78         caddr_t dest = dest_arg;
  79
  80         if (src < dest && (src + count) > dest) {
  81                 /* overlap copy */
  82                 while (--count != -1)
  83                         *(dest + count) = *(src + count);
  84         } else {
  85                 while (--count != -1)
  86                         *dest++ = *src++;
  87         }
  88 }
  89
  90 static size_t
  91 stand_strlcat(char *dst, const char *src, size_t dstsize)
  92 {
  93         char *df = dst;
  94         size_t left = dstsize;
  95         size_t l1;
  96         size_t l2 = strlen(src);
  97         size_t copied;
  98
  99         while (left-- != 0 && *df != '\0')
 100                 df++;
 101         l1 = df - dst;
 102         if (dstsize == l1)
 103                 return (l1 + l2);
 104
 105         copied = l1 + l2 >= dstsize ? dstsize - l1 - 1 : l2;
 106         bcopy(src, dst + l1, copied);
 107         dst[l1+copied] = '\0';
 108         return (l1 + l2);
 109 }
 110
 111 /*
 112  * Set up the krtld standalone utilty vectors
 113  */
 114 void
 115 kobj_setup_standalone_vectors()
 116 {
 117         _kobj_printf = bop_printf;
 118         _vkobj_printf = vbop_printf;
 119         kobj_bcopy = stand_bcopy;
 120         kobj_bzero = stand_bzero;
 121         kobj_strlcat = stand_strlcat;
 122 }
 123
 124 /*
 125  * Restore the kprintf/vkprintf/bcopy/bzero kobj vectors.
 126  * We need to undefine the override macros to
 127  * accomplish this.
 128  *
 129  * Do NOT add new code after the point or at least
 130  * certainly not code using bcopy or bzero which would
 131  * need to be vectored to the krtld equivalents.
 132  */
 133 #undef  bcopy
 134 #undef  bzero
 135 #undef  strlcat
 136
 137 void
 138 kobj_restore_vectors()
 139 {
 140         _kobj_printf = kprintf;
 141         _vkobj_printf = vkprintf;
 142         kobj_bcopy = bcopy;
 143         kobj_bzero = bzero;
 144         kobj_strlcat = strlcat;
 145 }