mDNSShared/dnssd_ipc.c

   1 /* -*- Mode: C; tab-width: 4 -*-
   2  *
   3  * Copyright (c) 2003-2011 Apple 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 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 }