compat/cmsg.h

   1 /*
   2  * Copyright (C) 1996-2018 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 #ifndef SQUID_COMPAT_CMSG_H
  10 #define SQUID_COMPAT_CMSG_H
  11
  12 /*
  13  * Compatibility-layer for CMSG_
  14  */
  15
  16 // cmsg.h is found through sys/socket.h
  17 #if HAVE_SYS_SOCKET_H
  18 #include <sys/socket.h>
  19 #endif
  20
  21 // mswsock.h defines WSA_CMSG definitions
  22 #if HAVE_MSWSOCK_H
  23 #include <mswsock.h>
  24 #endif
  25 #if HAVE_WINSOCK2_H
  26 #include <winsock2.h>
  27 #endif
  28
  29 // sockaddr_un might be in sys/un.h if not pulled in already
  30 #if HAVE_SYS_UN_H
  31 #include <sys/un.h>
  32 #endif
  33
  34 #if !HAVE_CMSGHDR
  35 struct cmsghdr {
  36     unsigned int cmsg_len;
  37     int cmsg_level;
  38     int cmsg_type;
  39     unsigned char cmsg_data[16]; /* dummy */
  40     /* followed by UCHAR cmsg_data[]; */
  41 };
  42 #endif
  43
  44 /* lifted off https://metacpan.org/source/SAMPO/Socket-PassAccessRights-0.03/passfd.c */
  45 // check for WSA_CMSG first because Windows defines CMSG_DATA for other uses
  46 #if defined(WSA_CMSG_DATA)
  47 # define SQUID_CMSG_DATA(cmsg) WSA_CMSG_DATA(cmsg)
  48 #elif defined(CMSG_DATA)
  49 # define SQUID_CMSG_DATA(cmsg) CMSG_DATA(cmsg)
  50 #else
  51 # define SQUID_CMSG_DATA(cmsg) ((cmsg)->cmsg_data)
  52 #endif
  53
  54 #ifndef CMSG_NXTHDR
  55 # define CMSG_NXTHDR(mhdr, X) __cmsg_nxthdr (mhdr, X)
  56 #endif
  57
  58 #ifndef CMSG_FIRSTHDR
  59 # define CMSG_FIRSTHDR(mhdr) \
  60   ((size_t) (mhdr)->msg_controllen >= sizeof (struct cmsghdr)        \
  61    ? (struct cmsghdr *) (mhdr)->msg_control : (struct cmsghdr *) NULL)
  62 #endif
  63
  64 #ifndef CMSG_ALIGN
  65 # define CMSG_ALIGN(len) (((len) + sizeof (size_t) - 1) \
  66              & ~(sizeof (size_t) - 1))
  67 #endif
  68
  69 #ifndef CMSG_SPACE
  70 # define CMSG_SPACE(len) (CMSG_ALIGN (len) \
  71              + CMSG_ALIGN (sizeof (struct cmsghdr)))
  72 #undef HAVE_CONSTANT_CMSG_SPACE
  73 #define HAVE_CONSTANT_CMSG_SPACE 1
  74 #endif
  75
  76 #ifndef CMSG_LEN
  77 # define CMSG_LEN(len)   (CMSG_ALIGN (sizeof (struct cmsghdr)) + (len))
  78 #endif
  79
  80 #if !HAVE_IOVEC
  81 struct iovec {
  82     void *iov_base;
  83     size_t iov_len;
  84 };
  85 #endif
  86
  87 #if !HAVE_MSGHDR
  88 struct msghdr {
  89     void *msg_name;             /* Address to send to/receive from.  */
  90     socklen_t msg_namelen;      /* Length of address data.  */
  91
  92     struct iovec *msg_iov;      /* Vector of data to send/receive into.  */
  93     size_t msg_iovlen;          /* Number of elements in the vector.  */
  94
  95     void *msg_control;          /* Ancillary data (eg BSD filedesc passing). */
  96     size_t msg_controllen;      /* Ancillary data buffer length.
  97                                    !! The type should be socklen_t but the
  98                                    definition of the kernel is incompatible
  99                                    with this.  */
 100
 101     int msg_flags;              /* Flags on received message.  */
 102 };
 103 #endif
 104
 105 #if !HAVE_SOCKADDR_UN
 106 struct sockaddr_un {
 107     char sun_family;
 108     char sun_path[256];   /* pathname */
 109 };
 110 #endif
 111
 112 #ifndef SUN_LEN
 113 # define SUN_LEN(ptr) ((size_t) (((struct sockaddr_un *) 0)->sun_path)        \
 114         + strlen ((ptr)->sun_path))
 115 #endif
 116
 117 #ifndef SCM_RIGHTS
 118 #define SCM_RIGHTS 1
 119 #endif
 120 #ifndef SCM_CREDENTIALS
 121 #define SCM_CREDENTIALS 2
 122 #endif
 123 #ifndef SCM_SECURITY
 124 #define SCM_SECURITY 3
 125 #endif
 126
 127 #ifndef AF_LOCAL
 128 #define AF_LOCAL 1
 129 #endif
 130
 131 // CMSG_SPACE is not constant on some systems (in particular Max OS X),
 132 // provide a replacement that can be used at build time in that case
 133 // NP: this must go below our replacement definitions.
 134
 135 #if HAVE_CONSTANT_CMSG_SPACE
 136 #define SQUID_CMSG_SPACE CMSG_SPACE
 137 #else
 138 // add 16 bytes for header and data alignment
 139 #define SQUID_CMSG_SPACE(len) (sizeof(struct cmsghdr) + (len) + 16)
 140 #endif
 141
 142 #endif /* SQUID_COMPAT_CMSG_H */
 143