hphp/util/afdt-util.cpp

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present Facebook, Inc. (http://www.facebook.com)  |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16 #include "hphp/util/afdt-util.h"
  17 #include <afdt.h>
  18 #include <fcntl.h>
  19 #include <errno.h>
  20 #include <limits.h>
  21 #include <system_error>
  22
  23 #include "hphp/util/assertions.h"
  24
  25 namespace HPHP {
  26 namespace afdt {
  27 ///////////////////////////////////////////////////////////////////////////////
  28
  29 namespace detail {
  30
  31 namespace {
  32 void append(std::vector<iovec>& iov, const void* addr, size_t size) {
  33   if (!size) return;
  34
  35   iovec io;
  36   io.iov_base = const_cast<void*>(addr);
  37   io.iov_len = size;
  38   iov.push_back(io);
  39 }
  40 }
  41
  42 void sappend(int afdt_fd,
  43              std::vector<iovec>& iov, const void* addr, size_t size) {
  44   if (iov.size() == IOV_MAX) {
  45     send(afdt_fd, iov);
  46     iov.clear();
  47   }
  48   append(iov, addr, size);
  49 }
  50
  51 void rappend(int afdt_fd,
  52              std::vector<iovec>& iov, void* addr, size_t size) {
  53   if (iov.size() == IOV_MAX) {
  54     recv(afdt_fd, iov);
  55     iov.clear();
  56   }
  57   append(iov, addr, size);
  58 }
  59
  60 void send(int afdt_fd, std::vector<iovec>& iov) {
  61   if (iov.size() == 0) return;
  62
  63   struct msghdr msg;
  64   memset(&msg, 0, sizeof(msg));
  65   msg.msg_iov = &iov[0];
  66   msg.msg_iovlen = iov.size();
  67   ssize_t nwritten = sendmsg(afdt_fd, &msg, MSG_WAITALL);
  68   if (nwritten < 0) {
  69     throw std::system_error(errno, std::generic_category(), "send failed");
  70   }
  71   for (auto& io : iov) {
  72     nwritten -= io.iov_len;
  73   }
  74   if (nwritten) throw std::runtime_error("sent wrong number of bytes");
  75 }
  76
  77 void recv(int afdt_fd, std::vector<iovec>& iov) {
  78   if (iov.size() == 0) return;
  79
  80   struct msghdr msg;
  81   memset(&msg, 0, sizeof(msg));
  82   msg.msg_iov = &iov[0];
  83   msg.msg_iovlen = iov.size();
  84   ssize_t nread = recvmsg(afdt_fd, &msg, MSG_WAITALL);
  85   if (nread <= 0) {
  86     throw std::system_error(errno, std::generic_category(), "recv failed");
  87   }
  88   for (auto& io : iov) {
  89     nread -= io.iov_len;
  90   }
  91   if (nread) throw std::runtime_error("recv received wrong number of bytes");
  92 }
  93
  94 }
  95
  96 bool send_fd(int afdt_fd, int fd) {
  97   afdt_error_t err = AFDT_ERROR_T_INIT;
  98   errno = 0;
  99   int ret = afdt_send_fd_msg(afdt_fd, nullptr, 0, fd, &err);
 100   if (ret < 0 && errno == 0) {
 101     // Set non-empty errno if afdt_send_fd_msg doesn't set one on error
 102     errno = EPROTO;
 103   }
 104   return ret >= 0;
 105 }
 106
 107 int recv_fd(int afdt_fd) {
 108 #ifdef __APPLE__
 109   {
 110     errno = 0;
 111     int flags = fcntl(0, F_GETFD);
 112     always_assert(flags != -1 || errno != EBADF);
 113   }
 114 #endif
 115   int fd;
 116   afdt_error_t err = AFDT_ERROR_T_INIT;
 117   uint32_t afdt_len = 0;
 118   errno = 0;
 119   if (afdt_recv_fd_msg(afdt_fd, nullptr, &afdt_len, &fd, &err) < 0) {
 120     if (errno == 0) {
 121       // Set non-empty errno if afdt_send_fd_msg doesn't set one on error
 122       errno = EPROTO;
 123     }
 124     return -1;
 125   }
 126   return fd;
 127 }
 128
 129 ///////////////////////////////////////////////////////////////////////////////
 130 }}