xapian-applications/omega/worker_comms.h

   1 /** @file
   2  * @brief Communication with worker processes
   3  */
   4 /* Copyright (C) 2011,2022 Olly Betts
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 2 of the
   9  * License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301
  19  * USA
  20  */
  21
  22 #include <cstdio>
  23 #include <string>
  24
  25 /// Read a string from the file descriptor @a f and storage it in @a s.
  26 bool read_string(std::FILE* f, std::string& s);
  27
  28 /// Write the string @a p of length @a len to the file descriptor @a f.
  29 bool write_string(std::FILE* f, const char* p, size_t len);
  30
  31 /// Write the string @a p of length @a len to the file descriptor @a f.
  32 inline bool write_string(std::FILE* f, const std::string& s) {
  33     return write_string(f, s.data(), s.size());
  34 }
  35
  36 bool read_unsigned(std::FILE* f, unsigned& v);
  37
  38 bool read_unsigned(std::FILE* f, unsigned long& v);
  39
  40 bool write_unsigned(std::FILE* f, unsigned v);
  41
  42 bool write_unsigned(std::FILE* f, unsigned long v);
  43
  44 // Exit codes for situations not enumerated by <sysexits.h>.
  45 enum {
  46     OMEGA_EX_SOCKET_READ_ERROR = 10,
  47     OMEGA_EX_SOCKET_WRITE_ERROR
  48 };