mDNSShared/dnssd_ipc.c

   1 /* -*- Mode: C; tab-width: 4 -*-
   2  *
   3  * Copyright (c) 2003-2004, Apple Computer, Inc. All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are met:
   7  *
   8  * 1.  Redistributions of source code must retain the above copyright notice,
   9  *     this list of conditions and the following disclaimer.
  10  * 2.  Redistributions in binary form must reproduce the above copyright notice,
  11  *     this list of conditions and the following disclaimer in the documentation
  12  *     and/or other materials provided with the distribution.
  13  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of its
  14  *     contributors may be used to endorse or promote products derived from this
  15  *     software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  21  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  26  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include "dnssd_ipc.h"
  30
  31 #if defined(_WIN32)
  32
  33 char *win32_strerror(int inErrorCode)
  34         {
  35         static char buffer[1024];
  36         DWORD       n;
  37         memset(buffer, 0, sizeof(buffer));
  38         n = FormatMessageA(
  39                         FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
  40                         NULL,
  41                         (DWORD) inErrorCode,
  42                         MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
  43                         buffer,
  44                         sizeof(buffer),
  45                         NULL);
  46         if (n > 0)
  47                 {
  48                 // Remove any trailing CR's or LF's since some messages have them.
  49                 while ((n > 0) && isspace(((unsigned char *) buffer)[n - 1]))
  50                         buffer[--n] = '\0';
  51                 }
  52         return buffer;
  53         }
  54
  55 #endif
  56
  57 void put_uint32(const uint32_t l, char **ptr)
  58         {
  59         (*ptr)[0] = (char)((l >> 24) &  0xFF);
  60         (*ptr)[1] = (char)((l >> 16) &  0xFF);
  61         (*ptr)[2] = (char)((l >>  8) &  0xFF);
  62         (*ptr)[3] = (char)((l      ) &  0xFF);
  63         *ptr += sizeof(uint32_t);
  64         }
  65
  66 uint32_t get_uint32(const char **ptr, const char *end)
  67         {
  68         if (!*ptr || *ptr + sizeof(uint32_t) > end)
  69                 {
  70                 *ptr = NULL;
  71                 return(0);
  72                 }
  73         else
  74                 {
  75                 uint8_t *p = (uint8_t*) *ptr;
  76                 *ptr += sizeof(uint32_t);
  77                 return((uint32_t) ((uint32_t)p[0] << 24 | (uint32_t)p[1] << 16 | (uint32_t)p[2] << 8 | p[3]));
  78                 }
  79         }
  80
  81 void put_uint16(uint16_t s, char **ptr)
  82         {
  83         (*ptr)[0] = (char)((s >>  8) &  0xFF);
  84         (*ptr)[1] = (char)((s      ) &  0xFF);
  85         *ptr += sizeof(uint16_t);
  86         }
  87
  88 uint16_t get_uint16(const char **ptr, const char *end)
  89         {
  90         if (!*ptr || *ptr + sizeof(uint16_t) > end)
  91                 {
  92                 *ptr = NULL;
  93                 return(0);
  94                 }
  95         else
  96                 {
  97                 uint8_t *p = (uint8_t*) *ptr;
  98                 *ptr += sizeof(uint16_t);
  99                 return((uint16_t) ((uint16_t)p[0] << 8 | p[1]));
 100                 }
 101         }
 102
 103 int put_string(const char *str, char **ptr)
 104         {
 105         if (!str) str = "";
 106         strcpy(*ptr, str);
 107         *ptr += strlen(str) + 1;
 108         return 0;
 109         }
 110
 111 int get_string(const char **ptr, const char *const end, char *buffer, int buflen)
 112         {
 113         if (!*ptr)
 114                 {
 115                 *buffer = 0;
 116                 return(-1);
 117                 }
 118         else
 119                 {
 120                 char *lim = buffer + buflen;    // Calculate limit
 121                 while (*ptr < end && buffer < lim)
 122                         {
 123                         char c = *buffer++ = *(*ptr)++;
 124                         if (c == 0) return(0);          // Success
 125                         }
 126                 if (buffer == lim) buffer--;
 127                 *buffer = 0;                                    // Failed, so terminate string,
 128                 *ptr = NULL;                                    // clear pointer,
 129                 return(-1);                                             // and return failure indication
 130                 }
 131         }
 132
 133 void put_rdata(const int rdlen, const unsigned char *rdata, char **ptr)
 134         {
 135         memcpy(*ptr, rdata, rdlen);
 136         *ptr += rdlen;
 137         }
 138
 139 const char *get_rdata(const char **ptr, const char *end, int rdlen)
 140         {
 141         if (!*ptr || *ptr + rdlen > end)
 142                 {
 143                 *ptr = NULL;
 144                 return(0);
 145                 }
 146         else
 147                 {
 148                 const char *rd = *ptr;
 149                 *ptr += rdlen;
 150                 return rd;
 151                 }
 152         }
 153
 154 void ConvertHeaderBytes(ipc_msg_hdr *hdr)
 155         {
 156         hdr->version   = htonl(hdr->version);
 157         hdr->datalen   = htonl(hdr->datalen);
 158         hdr->ipc_flags = htonl(hdr->ipc_flags);
 159         hdr->op        = htonl(hdr->op );
 160         hdr->reg_index = htonl(hdr->reg_index);
 161         }