/src/haproxy/include/haproxy/fd-t.h

Source
/*
 * include/haproxy/fd-t.h
 * File descriptors states - check src/fd.c for explanations.
 *
 * Copyright (C) 2000-2014 Willy Tarreau - w@1wt.eu
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation, version 2.1
 * exclusively.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#ifndef _HAPROXY_FD_T_H
#define _HAPROXY_FD_T_H

#include <haproxy/api-t.h>
#include <haproxy/port_range-t.h>
#include <haproxy/show_flags-t.h>

/* Direction for each FD event update */
enum {
  DIR_RD=0,
  DIR_WR=1,
};


/* fdtab[].state is a composite state describing what is known about the FD.
 * For now, the following information are stored in it:
 *   - event configuration and status for each direction (R,W) split into
 *     active, ready, shutdown categories (FD_EV_*). These are known by their
 *     bit values as well so that test-and-set bit operations are possible.
 *
 *   - last known polling status (FD_POLL_*). For ease of troubleshooting,
 *     avoid visually mixing these ones with the other ones above. 3 of these
 *     flags are updated on each poll() report (FD_POLL_IN, FD_POLL_OUT,
 *     FD_POLL_PRI). FD_POLL_HUP and FD_POLL_ERR are "sticky" in that once they
 *     are reported, they will not be cleared until the FD is closed.
 */

/* bits positions for a few flags */
#define FD_EV_ACTIVE_R_BIT 0
#define FD_EV_READY_R_BIT  1
#define FD_EV_SHUT_R_BIT   2
/* unused: 3 */

#define FD_EV_ACTIVE_W_BIT 4
#define FD_EV_READY_W_BIT  5
#define FD_EV_SHUT_W_BIT   6
#define FD_EV_ERR_RW_BIT   7

#define FD_POLL_IN_BIT     8
#define FD_POLL_PRI_BIT    9
#define FD_POLL_OUT_BIT   10
#define FD_POLL_ERR_BIT   11
#define FD_POLL_HUP_BIT   12

/* info/config bits */
#define FD_LINGER_RISK_BIT 16  /* must kill lingering before closing */
#define FD_CLONED_BIT      17  /* cloned socket, requires EPOLL_CTL_DEL on close */
#define FD_INITIALIZED_BIT 18  /* init phase was done (e.g. output pipe set non-blocking) */
#define FD_ET_POSSIBLE_BIT 19  /* edge-triggered is possible on this FD */
#define FD_EXPORTED_BIT    20  /* FD is exported and must not be closed */
#define FD_EXCL_SYSCALL_BIT 21 /* a syscall claims exclusivity on this FD */
#define FD_DISOWN_BIT      22  /* this fd will be closed by some external code */
#define FD_MUST_CLOSE_BIT  23  /* this fd will be closed by some external code */
#define FD_HAS_PORT_BIT    24  /* This fd had a port allocated from a port range */
#define FD_OWNER_PR_BIT    27 /* The owner is actually a port range */


/* and flag values */
#define FD_EV_ACTIVE_R  (1U << FD_EV_ACTIVE_R_BIT)
#define FD_EV_ACTIVE_W  (1U << FD_EV_ACTIVE_W_BIT)
#define FD_EV_ACTIVE_RW (FD_EV_ACTIVE_R | FD_EV_ACTIVE_W)

#define FD_EV_READY_R   (1U << FD_EV_READY_R_BIT)
#define FD_EV_READY_W   (1U << FD_EV_READY_W_BIT)
#define FD_EV_READY_RW  (FD_EV_READY_R | FD_EV_READY_W)

/* note that when FD_EV_SHUT is set, ACTIVE and READY are cleared */
#define FD_EV_SHUT_R    (1U << FD_EV_SHUT_R_BIT)
#define FD_EV_SHUT_W    (1U << FD_EV_SHUT_W_BIT)
#define FD_EV_SHUT_RW   (FD_EV_SHUT_R | FD_EV_SHUT_W)

/* note that when FD_EV_ERR is set, SHUT is also set. Also, ERR is for both
 * directions at once (write error, socket dead, etc).
 */
#define FD_EV_ERR_RW    (1U << FD_EV_ERR_RW_BIT)

/* mask covering all use cases above */
#define FD_EV_ANY       (FD_EV_ACTIVE_RW | FD_EV_READY_RW | FD_EV_SHUT_RW | FD_EV_ERR_RW)

/* polling status */
#define FD_POLL_IN          (1U << FD_POLL_IN_BIT)
#define FD_POLL_PRI         (1U << FD_POLL_PRI_BIT)
#define FD_POLL_OUT         (1U << FD_POLL_OUT_BIT)
#define FD_POLL_ERR         (1U << FD_POLL_ERR_BIT)
#define FD_POLL_HUP         (1U << FD_POLL_HUP_BIT)
#define FD_POLL_UPDT_MASK   (FD_POLL_IN | FD_POLL_PRI | FD_POLL_OUT)
#define FD_POLL_ANY_MASK    (FD_POLL_IN | FD_POLL_PRI | FD_POLL_OUT | FD_POLL_ERR | FD_POLL_HUP)

/* information/configuration flags */
#define FD_LINGER_RISK      (1U << FD_LINGER_RISK_BIT)
#define FD_CLONED           (1U << FD_CLONED_BIT)
#define FD_INITIALIZED      (1U << FD_INITIALIZED_BIT)
#define FD_ET_POSSIBLE      (1U << FD_ET_POSSIBLE_BIT)
#define FD_EXPORTED         (1U << FD_EXPORTED_BIT)
#define FD_EXCL_SYSCALL     (1U << FD_EXCL_SYSCALL_BIT)
#define FD_DISOWN           (1U << FD_DISOWN_BIT)
#define FD_MUST_CLOSE       (1U << FD_MUST_CLOSE_BIT)
#define FD_HAS_PORT         (1U << FD_HAS_PORT_BIT)
#define FD_OWNER_PR         (1U << FD_OWNER_PR_BIT)

/* This function is used to report flags in debugging tools. Please reflect
 * below any single-bit flag addition above in the same order via the
 * __APPEND_FLAG macro. The new end of the buffer is returned.
 */
static forceinline char *fd_show_flags(char *buf, size_t len, const char *delim, uint flg)
{
#define _(f, ...) __APPEND_FLAG(buf, len, delim, flg, f, #f, __VA_ARGS__)
  /* prologue */
  _(0);
  /* flags */
  _(FD_EV_ACTIVE_R, _(FD_EV_ACTIVE_W, _(FD_EV_READY_R, _(FD_EV_READY_W,
  _(FD_EV_SHUT_R, _(FD_EV_SHUT_W, _(FD_EV_ERR_RW, _(FD_POLL_IN,
  _(FD_POLL_PRI, _(FD_POLL_OUT, _(FD_POLL_ERR, _(FD_POLL_HUP,
  _(FD_LINGER_RISK, _(FD_CLONED, _(FD_INITIALIZED, _(FD_ET_POSSIBLE,
  _(FD_EXPORTED, _(FD_EXCL_SYSCALL, _(FD_DISOWN)))))))))))))))))));
  /* epilogue */
  _(~0U);
  return buf;
#undef _
}

/* FD update status after fd_update_events() */
enum {
  FD_UPDT_DONE = 0,    // update done, nothing else to be done
  FD_UPDT_CLOSED,      // FD was closed
  FD_UPDT_MIGRATED,    // FD was migrated, ignore it now
};

/* This is the value used to mark a file descriptor as dead. This value is
 * negative, this is important so that tests on fd < 0 properly match. It
 * also has the nice property of being highly negative but neither overflowing
 * nor changing sign on 32-bit machines when multiplied by sizeof(fdtab).
 * This ensures that any unexpected dereference of such an uninitialized
 * file descriptor will lead to so large a dereference that it will crash
 * the process at the exact location of the bug with a clean stack trace
 * instead of causing silent manipulation of other FDs. And it's readable
 * when found in a dump.
 */
#define DEAD_FD_MAGIC 0xFDDEADFD

/* fdlist_entry: entry used by the fd cache.
 *    >= 0 means we're in the cache and gives the FD of the next in the cache,
 *      -1 means we're in the cache and the last element,
 *      -2 means the entry is locked,
 *   <= -3 means not in the cache, and next element is -4-fd
 *
 * It must remain 8-aligned so that aligned CAS operations may be done on both
 * entries at once.
 */
struct fdlist_entry {
  int next;
  int prev;
} ALIGNED(8);

/* head of the fd cache, per-group */
struct fdlist {
  int first;
  int last;
} ALIGNED(64);

/* info about one given fd. Note: only align on cache lines when using threads;
 * 32-bit small archs can put everything in 32-bytes when threads are disabled.
 * refc_tgid is an atomic 32-bit composite value made of 16 higher bits
 * containing a refcount on tgid and the running_mask, and 16 lower bits
 * containing a thread group ID and a lock bit on the 16th. The tgid may only
 * be changed when refc is zero and running may only be checked/changed when
 * refc is held and shows the reader is alone. An FD with tgid zero belongs to
 * nobody.
 */
struct fdtab {
  unsigned long running_mask;          /* mask of thread IDs currently using the fd */
  unsigned long thread_mask;           /* mask of thread IDs authorized to process the fd */
  unsigned long update_mask;           /* mask of thread IDs having an update for fd */
  struct fdlist_entry update;          /* Entry in the global update list */
  void (*iocb)(int fd);                /* I/O handler */
  void *owner;                         /* the connection or listener associated with this fd, NULL if closed */
  unsigned int state;                  /* FD state for read and write directions (FD_EV_*) + FD_POLL_* */
  unsigned int refc_tgid;              /* refcounted tgid, updated atomically */
  /* the info below are mainly used for epoll debugging/strengthening.
   * they're filling the rest of the cache line but may easily be dropped
   * if the room is needed for more important stuff.
   */
  unsigned int nb_takeover;            /* number of times this FD was taken over since inserted (used for debugging) */
  unsigned int generation;             /* number of times this FD was closed before (used for epoll strengthening) */
#ifdef DEBUG_FD
  unsigned int event_count;            /* number of events reported */
#endif
} THREAD_ALIGNED();

/* polled mask, one bit per thread and per direction for each FD */
struct polled_mask {
  unsigned long poll_recv;
  unsigned long poll_send;
};

/*
 * Poller descriptors.
 *  - <name> is initialized by the poller's register() function, and should not
 *    be allocated, just linked to.
 *  - <pref> is initialized by the poller's register() function. It is set to 0
 *    by default, meaning the poller is disabled. init() should set it to 0 in
 *    case of failure. term() must set it to 0. A generic unoptimized select()
 *    poller should set it to 100.
 *  - <private> is initialized by the poller's init() function, and cleaned by
 *    the term() function.
 *  - clo() should be used to do indicate the poller that fd will be closed.
 *  - poll() calls the poller, expiring at <exp>, or immediately if <wake> is set
 *  - flags indicate what the poller supports (HAP_POLL_F_*)
 */

#define HAP_POLL_F_RDHUP        0x00000001                   /* the poller notifies of HUP with reads */
#define HAP_POLL_F_ERRHUP       0x00000002                   /* the poller reports ERR and HUP */
#define HAP_POLL_F_NO_FD_SHARING 0x00000004                  /* the poller supports not sharing fds across thread groups */

struct poller {
  void   *private;                                     /* any private data for the poller */
  void   (*clo)(const int fd);                 /* mark <fd> as closed */
  void   (*poll)(struct poller *p, int exp, int wake);  /* the poller itself */
  int    (*init)(struct poller *p);            /* poller initialization */
  void   (*term)(struct poller *p);            /* termination of this poller */
  int    (*test)(struct poller *p);            /* pre-init check of the poller */
  int    (*fork)(struct poller *p);            /* post-fork re-opening */
  void   (*fixup_tgid_takeover)(struct poller *p, const int fd, const int old_tid, const int old_tgid); /* Fixup anything necessary after a FD takeover across tgids */
  const char   *name;                                  /* poller name */
  unsigned int flags;                                  /* HAP_POLL_F_* */
  int    pref;                                         /* try pollers with higher preference first */
};

#endif /* _HAPROXY_FD_T_H */

/*
 * Local variables:
 *  c-indent-level: 8
 *  c-basic-offset: 8
 * End:
 */

Coverage Report

Created: 2026-09-03 06:33

Line	Count	Source
1		/*
2		* include/haproxy/fd-t.h
3		* File descriptors states - check src/fd.c for explanations.
4		*
5		* Copyright (C) 2000-2014 Willy Tarreau - w@1wt.eu
6		*
7		* This library is free software; you can redistribute it and/or
8		* modify it under the terms of the GNU Lesser General Public
9		* License as published by the Free Software Foundation, version 2.1
10		* exclusively.
11		*
12		* This library is distributed in the hope that it will be useful,
13		* but WITHOUT ANY WARRANTY; without even the implied warranty of
14		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15		* Lesser General Public License for more details.
16		*
17		* You should have received a copy of the GNU Lesser General Public
18		* License along with this library; if not, write to the Free Software
19		* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20		*/
21
22		#ifndef _HAPROXY_FD_T_H
23		#define _HAPROXY_FD_T_H
24
25		#include <haproxy/api-t.h>
26		#include <haproxy/port_range-t.h>
27		#include <haproxy/show_flags-t.h>
28
29		/* Direction for each FD event update */
30		enum {
31		DIR_RD=0,
32		DIR_WR=1,
33		};
34
35
36		/* fdtab[].state is a composite state describing what is known about the FD.
37		* For now, the following information are stored in it:
38		* - event configuration and status for each direction (R,W) split into
39		* active, ready, shutdown categories (FD_EV_*). These are known by their
40		* bit values as well so that test-and-set bit operations are possible.
41		*
42		* - last known polling status (FD_POLL_*). For ease of troubleshooting,
43		* avoid visually mixing these ones with the other ones above. 3 of these
44		* flags are updated on each poll() report (FD_POLL_IN, FD_POLL_OUT,
45		* FD_POLL_PRI). FD_POLL_HUP and FD_POLL_ERR are "sticky" in that once they
46		* are reported, they will not be cleared until the FD is closed.
47		*/
48
49		/* bits positions for a few flags */
50	0	#define FD_EV_ACTIVE_R_BIT 0
51	0	#define FD_EV_READY_R_BIT 1
52	0	#define FD_EV_SHUT_R_BIT 2
53		/* unused: 3 */
54
55	0	#define FD_EV_ACTIVE_W_BIT 4
56	0	#define FD_EV_READY_W_BIT 5
57	0	#define FD_EV_SHUT_W_BIT 6
58	0	#define FD_EV_ERR_RW_BIT 7
59
60	0	#define FD_POLL_IN_BIT 8
61	0	#define FD_POLL_PRI_BIT 9
62	0	#define FD_POLL_OUT_BIT 10
63	0	#define FD_POLL_ERR_BIT 11
64	0	#define FD_POLL_HUP_BIT 12
65
66		/* info/config bits */
67	0	#define FD_LINGER_RISK_BIT 16 /* must kill lingering before closing */
68	0	#define FD_CLONED_BIT 17 /* cloned socket, requires EPOLL_CTL_DEL on close */
69		#define FD_INITIALIZED_BIT 18 /* init phase was done (e.g. output pipe set non-blocking) */
70	0	#define FD_ET_POSSIBLE_BIT 19 /* edge-triggered is possible on this FD */
71	0	#define FD_EXPORTED_BIT 20 /* FD is exported and must not be closed */
72		#define FD_EXCL_SYSCALL_BIT 21 /* a syscall claims exclusivity on this FD */
73	0	#define FD_DISOWN_BIT 22 /* this fd will be closed by some external code */
74		#define FD_MUST_CLOSE_BIT 23 /* this fd will be closed by some external code */
75		#define FD_HAS_PORT_BIT 24 /* This fd had a port allocated from a port range */
76		#define FD_OWNER_PR_BIT 27 /* The owner is actually a port range */
77
78
79		/* and flag values */
80	0	#define FD_EV_ACTIVE_R (1U << FD_EV_ACTIVE_R_BIT)
81	0	#define FD_EV_ACTIVE_W (1U << FD_EV_ACTIVE_W_BIT)
82	0	#define FD_EV_ACTIVE_RW (FD_EV_ACTIVE_R \| FD_EV_ACTIVE_W)
83
84	0	#define FD_EV_READY_R (1U << FD_EV_READY_R_BIT)
85	0	#define FD_EV_READY_W (1U << FD_EV_READY_W_BIT)
86		#define FD_EV_READY_RW (FD_EV_READY_R \| FD_EV_READY_W)
87
88		/* note that when FD_EV_SHUT is set, ACTIVE and READY are cleared */
89	0	#define FD_EV_SHUT_R (1U << FD_EV_SHUT_R_BIT)
90	0	#define FD_EV_SHUT_W (1U << FD_EV_SHUT_W_BIT)
91		#define FD_EV_SHUT_RW (FD_EV_SHUT_R \| FD_EV_SHUT_W)
92
93		/* note that when FD_EV_ERR is set, SHUT is also set. Also, ERR is for both
94		* directions at once (write error, socket dead, etc).
95		*/
96	0	#define FD_EV_ERR_RW (1U << FD_EV_ERR_RW_BIT)
97
98		/* mask covering all use cases above */
99		#define FD_EV_ANY (FD_EV_ACTIVE_RW \| FD_EV_READY_RW \| FD_EV_SHUT_RW \| FD_EV_ERR_RW)
100
101		/* polling status */
102	0	#define FD_POLL_IN (1U << FD_POLL_IN_BIT)
103	0	#define FD_POLL_PRI (1U << FD_POLL_PRI_BIT)
104	0	#define FD_POLL_OUT (1U << FD_POLL_OUT_BIT)
105	0	#define FD_POLL_ERR (1U << FD_POLL_ERR_BIT)
106	0	#define FD_POLL_HUP (1U << FD_POLL_HUP_BIT)
107	0	#define FD_POLL_UPDT_MASK (FD_POLL_IN \| FD_POLL_PRI \| FD_POLL_OUT)
108		#define FD_POLL_ANY_MASK (FD_POLL_IN \| FD_POLL_PRI \| FD_POLL_OUT \| FD_POLL_ERR \| FD_POLL_HUP)
109
110		/* information/configuration flags */
111	0	#define FD_LINGER_RISK (1U << FD_LINGER_RISK_BIT)
112	0	#define FD_CLONED (1U << FD_CLONED_BIT)
113		#define FD_INITIALIZED (1U << FD_INITIALIZED_BIT)
114	0	#define FD_ET_POSSIBLE (1U << FD_ET_POSSIBLE_BIT)
115	0	#define FD_EXPORTED (1U << FD_EXPORTED_BIT)
116		#define FD_EXCL_SYSCALL (1U << FD_EXCL_SYSCALL_BIT)
117	0	#define FD_DISOWN (1U << FD_DISOWN_BIT)
118		#define FD_MUST_CLOSE (1U << FD_MUST_CLOSE_BIT)
119		#define FD_HAS_PORT (1U << FD_HAS_PORT_BIT)
120		#define FD_OWNER_PR (1U << FD_OWNER_PR_BIT)
121
122		/* This function is used to report flags in debugging tools. Please reflect
123		* below any single-bit flag addition above in the same order via the
124		* __APPEND_FLAG macro. The new end of the buffer is returned.
125		*/
126		static forceinline char fd_show_flags(char buf, size_t len, const char *delim, uint flg)
127	0	{
128	0	#define _(f, ...) __APPEND_FLAG(buf, len, delim, flg, f, #f, __VA_ARGS__)
129	0	/* prologue */
130	0	_(0);
131	0	/* flags */
132	0	_(FD_EV_ACTIVE_R, _(FD_EV_ACTIVE_W, _(FD_EV_READY_R, _(FD_EV_READY_W,
133	0	_(FD_EV_SHUT_R, _(FD_EV_SHUT_W, _(FD_EV_ERR_RW, _(FD_POLL_IN,
134	0	_(FD_POLL_PRI, _(FD_POLL_OUT, _(FD_POLL_ERR, _(FD_POLL_HUP,
135	0	_(FD_LINGER_RISK, _(FD_CLONED, _(FD_INITIALIZED, _(FD_ET_POSSIBLE,
136	0	_(FD_EXPORTED, _(FD_EXCL_SYSCALL, _(FD_DISOWN)))))))))))))))))));
137	0	/* epilogue */
138	0	_(~0U);
139	0	return buf;
140	0	#undef _
141	0	} Unexecuted instantiation: tools.c:fd_show_flags Unexecuted instantiation: applet.c:fd_show_flags Unexecuted instantiation: cfgparse.c:fd_show_flags Unexecuted instantiation: channel.c:fd_show_flags Unexecuted instantiation: cli.c:fd_show_flags Unexecuted instantiation: connection.c:fd_show_flags Unexecuted instantiation: debug.c:fd_show_flags Unexecuted instantiation: dgram.c:fd_show_flags Unexecuted instantiation: errors.c:fd_show_flags Unexecuted instantiation: fd.c:fd_show_flags Unexecuted instantiation: frontend.c:fd_show_flags Unexecuted instantiation: haproxy.c:fd_show_flags Unexecuted instantiation: http_ana.c:fd_show_flags Unexecuted instantiation: http_ext.c:fd_show_flags Unexecuted instantiation: http_htx.c:fd_show_flags Unexecuted instantiation: http_rules.c:fd_show_flags Unexecuted instantiation: limits.c:fd_show_flags Unexecuted instantiation: listener.c:fd_show_flags Unexecuted instantiation: log.c:fd_show_flags Unexecuted instantiation: mailers.c:fd_show_flags Unexecuted instantiation: mworker.c:fd_show_flags Unexecuted instantiation: peers.c:fd_show_flags Unexecuted instantiation: pool.c:fd_show_flags Unexecuted instantiation: proto_rhttp.c:fd_show_flags Unexecuted instantiation: proto_sockpair.c:fd_show_flags Unexecuted instantiation: protocol.c:fd_show_flags Unexecuted instantiation: proxy.c:fd_show_flags Unexecuted instantiation: queue.c:fd_show_flags Unexecuted instantiation: resolvers.c:fd_show_flags Unexecuted instantiation: ring.c:fd_show_flags Unexecuted instantiation: sample.c:fd_show_flags Unexecuted instantiation: server.c:fd_show_flags Unexecuted instantiation: session.c:fd_show_flags Unexecuted instantiation: signal.c:fd_show_flags Unexecuted instantiation: sink.c:fd_show_flags Unexecuted instantiation: sock.c:fd_show_flags Unexecuted instantiation: sock_inet.c:fd_show_flags Unexecuted instantiation: stats-html.c:fd_show_flags Unexecuted instantiation: stats-proxy.c:fd_show_flags Unexecuted instantiation: stats.c:fd_show_flags Unexecuted instantiation: stconn.c:fd_show_flags Unexecuted instantiation: stick_table.c:fd_show_flags Unexecuted instantiation: stream.c:fd_show_flags Unexecuted instantiation: task.c:fd_show_flags Unexecuted instantiation: tcp_rules.c:fd_show_flags Unexecuted instantiation: tcpcheck.c:fd_show_flags Unexecuted instantiation: thread.c:fd_show_flags Unexecuted instantiation: trace.c:fd_show_flags Unexecuted instantiation: vars.c:fd_show_flags Unexecuted instantiation: action.c:fd_show_flags Unexecuted instantiation: activity.c:fd_show_flags Unexecuted instantiation: backend.c:fd_show_flags Unexecuted instantiation: cfgparse-global.c:fd_show_flags Unexecuted instantiation: cfgparse-listen.c:fd_show_flags Unexecuted instantiation: check.c:fd_show_flags Unexecuted instantiation: compression.c:fd_show_flags Unexecuted instantiation: dns.c:fd_show_flags Unexecuted instantiation: dns_ring.c:fd_show_flags Unexecuted instantiation: event_hdl.c:fd_show_flags Unexecuted instantiation: extcheck.c:fd_show_flags Unexecuted instantiation: filters.c:fd_show_flags Unexecuted instantiation: flt_decomp.c:fd_show_flags Unexecuted instantiation: flt_http_comp.c:fd_show_flags Unexecuted instantiation: haterm.c:fd_show_flags Unexecuted instantiation: http_fetch.c:fd_show_flags Unexecuted instantiation: lb_chash.c:fd_show_flags Unexecuted instantiation: lb_fwlc.c:fd_show_flags Unexecuted instantiation: mux_spop.c:fd_show_flags Unexecuted instantiation: pattern.c:fd_show_flags Unexecuted instantiation: payload.c:fd_show_flags Unexecuted instantiation: proto_tcp.c:fd_show_flags Unexecuted instantiation: stats-file.c:fd_show_flags Unexecuted instantiation: stats-json.c:fd_show_flags Unexecuted instantiation: cache.c:fd_show_flags Unexecuted instantiation: fcgi-app.c:fd_show_flags Unexecuted instantiation: flt_spoe.c:fd_show_flags
142
143		/* FD update status after fd_update_events() */
144		enum {
145		FD_UPDT_DONE = 0, // update done, nothing else to be done
146		FD_UPDT_CLOSED, // FD was closed
147		FD_UPDT_MIGRATED, // FD was migrated, ignore it now
148		};
149
150		/* This is the value used to mark a file descriptor as dead. This value is
151		* negative, this is important so that tests on fd < 0 properly match. It
152		* also has the nice property of being highly negative but neither overflowing
153		* nor changing sign on 32-bit machines when multiplied by sizeof(fdtab).
154		* This ensures that any unexpected dereference of such an uninitialized
155		* file descriptor will lead to so large a dereference that it will crash
156		* the process at the exact location of the bug with a clean stack trace
157		* instead of causing silent manipulation of other FDs. And it's readable
158		* when found in a dump.
159		*/
160	0	#define DEAD_FD_MAGIC 0xFDDEADFD
161
162		/* fdlist_entry: entry used by the fd cache.
163		* >= 0 means we're in the cache and gives the FD of the next in the cache,
164		* -1 means we're in the cache and the last element,
165		* -2 means the entry is locked,
166		* <= -3 means not in the cache, and next element is -4-fd
167		*
168		* It must remain 8-aligned so that aligned CAS operations may be done on both
169		* entries at once.
170		*/
171		struct fdlist_entry {
172		int next;
173		int prev;
174		} ALIGNED(8);
175
176		/* head of the fd cache, per-group */
177		struct fdlist {
178		int first;
179		int last;
180		} ALIGNED(64);
181
182		/* info about one given fd. Note: only align on cache lines when using threads;
183		* 32-bit small archs can put everything in 32-bytes when threads are disabled.
184		* refc_tgid is an atomic 32-bit composite value made of 16 higher bits
185		* containing a refcount on tgid and the running_mask, and 16 lower bits
186		* containing a thread group ID and a lock bit on the 16th. The tgid may only
187		* be changed when refc is zero and running may only be checked/changed when
188		* refc is held and shows the reader is alone. An FD with tgid zero belongs to
189		* nobody.
190		*/
191		struct fdtab {
192		unsigned long running_mask; /* mask of thread IDs currently using the fd */
193		unsigned long thread_mask; /* mask of thread IDs authorized to process the fd */
194		unsigned long update_mask; /* mask of thread IDs having an update for fd */
195		struct fdlist_entry update; /* Entry in the global update list */
196		void (iocb)(int fd); / I/O handler */
197		void owner; / the connection or listener associated with this fd, NULL if closed */
198		unsigned int state; /* FD state for read and write directions (FD_EV_) + FD_POLL_ */
199		unsigned int refc_tgid; /* refcounted tgid, updated atomically */
200		/* the info below are mainly used for epoll debugging/strengthening.
201		* they're filling the rest of the cache line but may easily be dropped
202		* if the room is needed for more important stuff.
203		*/
204		unsigned int nb_takeover; /* number of times this FD was taken over since inserted (used for debugging) */
205		unsigned int generation; /* number of times this FD was closed before (used for epoll strengthening) */
206		#ifdef DEBUG_FD
207		unsigned int event_count; /* number of events reported */
208		#endif
209		} THREAD_ALIGNED();
210
211		/* polled mask, one bit per thread and per direction for each FD */
212		struct polled_mask {
213		unsigned long poll_recv;
214		unsigned long poll_send;
215		};
216
217		/*
218		* Poller descriptors.
219		* - <name> is initialized by the poller's register() function, and should not
220		* be allocated, just linked to.
221		* - <pref> is initialized by the poller's register() function. It is set to 0
222		* by default, meaning the poller is disabled. init() should set it to 0 in
223		* case of failure. term() must set it to 0. A generic unoptimized select()
224		* poller should set it to 100.
225		* - <private> is initialized by the poller's init() function, and cleaned by
226		* the term() function.
227		* - clo() should be used to do indicate the poller that fd will be closed.
228		* - poll() calls the poller, expiring at <exp>, or immediately if <wake> is set
229		* - flags indicate what the poller supports (HAP_POLL_F_*)
230		*/
231
232		#define HAP_POLL_F_RDHUP 0x00000001 /* the poller notifies of HUP with reads */
233	0	#define HAP_POLL_F_ERRHUP 0x00000002 /* the poller reports ERR and HUP */
234	0	#define HAP_POLL_F_NO_FD_SHARING 0x00000004 /* the poller supports not sharing fds across thread groups */
235
236		struct poller {
237		void private; / any private data for the poller */
238		void (clo)(const int fd); / mark <fd> as closed */
239		void (poll)(struct poller p, int exp, int wake); /* the poller itself */
240		int (init)(struct poller p); /* poller initialization */
241		void (term)(struct poller p); /* termination of this poller */
242		int (test)(struct poller p); /* pre-init check of the poller */
243		int (fork)(struct poller p); /* post-fork re-opening */
244		void (fixup_tgid_takeover)(struct poller p, const int fd, const int old_tid, const int old_tgid); /* Fixup anything necessary after a FD takeover across tgids */
245		const char name; / poller name */
246		unsigned int flags; /* HAP_POLL_F_* */
247		int pref; /* try pollers with higher preference first */
248		};
249
250		#endif /* _HAPROXY_FD_T_H */
251
252		/*
253		* Local variables:
254		* c-indent-level: 8
255		* c-basic-offset: 8
256		* End:
257		*/