src/comm/Loops.h

   1 /*
   2  * Copyright (C) 1996-2020 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_SRC_COMM_LOOPS_H
  10 #define _SQUID_SRC_COMM_LOOPS_H
  11
  12 #include "comm/Flag.h"
  13 #include "comm/forward.h"
  14 #include "defines.h"
  15
  16 /* Comm layer select loops API.
  17  *
  18  * These API functions must be implemented by all FD IO loops used by Squid.
  19  * Defines are provided short-term for legacy code. These will disappear soon.
  20  */
  21
  22 namespace Comm
  23 {
  24
  25 /// Initialize the module on Squid startup
  26 void SelectLoopInit(void);
  27
  28 /// reset/undo/unregister the watch for an FD which was set by Comm::SetSelect()
  29 inline void
  30 ResetSelect(int fd)
  31 {
  32     SetSelect(fd, COMM_SELECT_READ|COMM_SELECT_WRITE, nullptr, nullptr, 0);
  33 }
  34
  35 /** Perform a select() or equivalent call.
  36  * This is used by the main select loop engine to check for FD with IO available.
  37  */
  38 Comm::Flag DoSelect(int);
  39
  40 void QuickPollRequired(void);
  41
  42 /**
  43  * Max number of UDP messages to receive per call to the UDP receive poller.
  44  * This is a per-port limit for ICP/HTCP ports.
  45  * DNS has a separate limit.
  46  */
  47 #if _SQUID_WINDOWS_
  48 #define INCOMING_UDP_MAX 1
  49 #else
  50 #define INCOMING_UDP_MAX 15
  51 #endif
  52
  53 /**
  54  * Max number of DNS messages to receive per call to DNS read handler
  55  */
  56 #if _SQUID_WINDOWS_
  57 #define INCOMING_DNS_MAX 1
  58 #else
  59 #define INCOMING_DNS_MAX 15
  60 #endif
  61
  62 /**
  63  * Max number of new TCP connections to accept per call to the TCP listener poller.
  64  * This is a per-port limit for HTTP/HTTPS ports.
  65  */
  66 #if _SQUID_WINDOWS_
  67 #define INCOMING_TCP_MAX 1
  68 #else
  69 #define INCOMING_TCP_MAX 10
  70 #endif
  71 #define INCOMING_TOTAL_MAX (INCOMING_TCP_MAX+INCOMING_UDP_MAX+INCOMING_DNS_MAX)
  72
  73 } // namespace Comm
  74
  75 #endif /* _SQUID_SRC_COMM_LOOPS_H */
  76