commit 9e45e2486f4e24552439cef43d61d841229a8fea
parent 4bc408168dd163218eabca11fed138bcb003c381
Author: Evgeny Grin (Karlson2k) <k2k@narod.ru>
Date: Fri, 11 Dec 2020 20:24:55 +0300
mhd_send.c: partial re-write, fixed, portability
Full re-write of sockets buffering and data pushing.
Fixed portability for non-Linux systems.
Lowered number of additional sys-calls.
Added workaround logic if main buffer/data push calls failed.
Diffstat:
2 files changed, 565 insertions(+), 148 deletions(-)
diff --git a/src/microhttpd/mhd_send.c b/src/microhttpd/mhd_send.c
@@ -1,6 +1,8 @@
/*
This file is part of libmicrohttpd
- Copyright (C) 2019 ng0 <ng0@n0.is>
+ Copyright (C) 2017,2020 Karlson2k (Evgeny Grin), Full re-write of buffering and
+ pushing, many bugs fixes, optimisations, sendfile() porting
+ Copyright (C) 2019 ng0 <ng0@n0.is>, Initial version of send() wrappers
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
@@ -21,9 +23,9 @@
/**
* @file microhttpd/mhd_send.c
* @brief Implementation of send() wrappers.
+ * @author Karlson2k (Evgeny Grin)
* @author ng0 (N. Gillmann)
* @author Christian Grothoff
- * @author Evgeny Grin
*/
/* Worth considering for future improvements and additions:
@@ -32,10 +34,6 @@
* large a chunk as possible to the socket. Alternatively,
* use madvise(..., MADV_SEQUENTIAL). */
-/* Functions to be used in: send_param_adapter, MHD_send_
- * and every place where sendfile(), sendfile64(), setsockopt()
- * are used. */
-
#include "mhd_send.h"
#ifdef MHD_LINUX_SOLARIS_SENDFILE
#include <sys/sendfile.h>
@@ -51,6 +49,7 @@
#endif /* HAVE_SYS_PARAM_H */
#include "mhd_assert.h"
+#include "mhd_limits.h"
/**
* sendfile() chuck size
@@ -107,6 +106,121 @@ MHD_send_init_static_vars_ (void)
/**
+ * Set required TCP_NODELAY state for connection socket
+ *
+ * The function automatically updates sk_nodelay state.
+ * @param connection the connection to manipulate
+ * @param nodelay_state the requested new state of socket
+ * @return true if succeed, false if failed
+ */
+static bool
+connection_set_nodelay_state_ (struct MHD_Connection *connection,
+ bool nodelay_state)
+{
+ const MHD_SCKT_OPT_BOOL_ off_val = 0;
+ const MHD_SCKT_OPT_BOOL_ on_val = 1;
+ int err_code;
+
+ if (0 == setsockopt (connection->socket_fd,
+ IPPROTO_TCP,
+ TCP_NODELAY,
+ (const void *) (nodelay_state ? &on_val : &off_val),
+ sizeof (off_val)))
+ {
+ connection->sk_nodelay = nodelay_state;
+ return true;
+ }
+ err_code = MHD_socket_get_error_ ();
+ switch (err_code)
+ {
+ case ENOTSOCK:
+ /* FIXME: Could be we are talking to a pipe, maybe remember this
+ and avoid all setsockopt() in the future? */
+ break;
+ case EBADF:
+ /* FIXME: should we die hard here? */
+ case EINVAL:
+ /* FIXME: optlen invalid, should at least log this, maybe die */
+ case EFAULT:
+ /* wopsie, should at least log this, FIXME: maybe die */
+ case ENOPROTOOPT:
+ /* optlen unknown, should at least log this */
+ default:
+#ifdef HAVE_MESSAGES
+ MHD_DLOG (connection->daemon,
+ _ ("Setting %s option to %s state failed: %s\n"),
+ "TCP_NODELAY",
+ nodelay_state ? _ ("ON") : _ ("OFF"),
+ MHD_socket_strerr_ (err_code));
+#endif /* HAVE_MESSAGES */
+ break;
+ }
+ return false;
+}
+
+
+#if defined(MHD_TCP_CORK_NOPUSH)
+/**
+ * Set required cork state for connection socket
+ *
+ * The function automatically updates sk_corked state.
+ * @param connection the connection to manipulate
+ * @param cork_state the requested new state of socket
+ * @return true if succeed, false if failed
+ */
+static bool
+connection_set_cork_state_ (struct MHD_Connection *connection,
+ bool cork_state)
+{
+ const MHD_SCKT_OPT_BOOL_ off_val = 0;
+ const MHD_SCKT_OPT_BOOL_ on_val = 1;
+ int err_code;
+
+ if (0 == setsockopt (connection->socket_fd,
+ IPPROTO_TCP,
+ MHD_TCP_CORK_NOPUSH,
+ (const void *) (cork_state ? &on_val : &off_val),
+ sizeof (off_val)))
+ {
+ connection->sk_corked = cork_state;
+ return true;
+ }
+ err_code = MHD_socket_get_error_ ();
+ switch (err_code)
+ {
+ case ENOTSOCK:
+ /* FIXME: Could be we are talking to a pipe, maybe remember this
+ and avoid all setsockopt() in the future? */
+ break;
+ case EBADF:
+ /* FIXME: should we die hard here? */
+ case EINVAL:
+ /* FIXME: optlen invalid, should at least log this, maybe die */
+ case EFAULT:
+ /* wopsie, should at least log this, FIXME: maybe die */
+ case ENOPROTOOPT:
+ /* optlen unknown, should at least log this */
+ default:
+#ifdef HAVE_MESSAGES
+ MHD_DLOG (connection->daemon,
+ _ ("Setting %s option to %s state failed: %s\n"),
+#ifdef TCP_CORK
+ "TCP_CORK",
+#else /* ! TCP_CORK */
+ "TCP_NOPUSH",
+#endif /* ! TCP_CORK */
+ cork_state ? _ ("ON") : _ ("OFF"),
+ MHD_socket_strerr_ (err_code));
+#endif /* HAVE_MESSAGES */
+ break;
+ }
+ return false;
+}
+
+
+#endif /* MHD_TCP_CORK_NOPUSH */
+
+/**
* Handle pre-send setsockopt calls.
*
* @param connection the MHD_Connection structure
@@ -126,96 +240,259 @@ pre_send_setopt (struct MHD_Connection *connection,
* Final piece is indicated by push_data == true. */
const bool buffer_data = (! push_data);
-#ifdef MHD_USE_MSG_MORE
- if (plain_send)
+ /* The goal is to minimise the total number of additional sys-calls
+ * before and after send().
+ * The following tricky (over-)complicated algorithm typically use zero,
+ * one or two additional sys-calls (depending on OS) for each response. */
+
+ if (buffer_data)
{
- /* MSG_MORE is used, no need for extra syscalls! */
- return;
- }
+ /* Need to buffer data if possible. */
+#ifdef MHD_USE_MSG_MORE
+ if (plain_send)
+ return; /* Data is buffered by send() with MSG_MORE flag.
+ * No need to check or change anything. */
#else /* ! MHD_USE_MSG_MORE */
- (void) plain_send; /* Mute compiler warning. */
+ (void) plain_send; /* Mute compiler warning. */
#endif /* ! MHD_USE_MSG_MORE */
-#if defined(MHD_TCP_CORK_NOPUSH)
- /* If connection is already in required corked state, do nothing. */
- if (connection->sk_corked == buffer_data)
- return;
- if (push_data)
- return; /* nothing to do *pre* syscall! BUG: to be fixed */
- ret = MHD_socket_cork_ (connection->socket_fd,
- buffer_data);
- if (0 != ret)
- {
- connection->sk_corked = buffer_data;
+#ifdef MHD_TCP_CORK_NOPUSH
+ if (_MHD_ON == connection->sk_corked)
+ return; /* The connection was already corked. */
+
+ if (connection_set_cork_state_ (connection, true))
+ return; /* The connection has been corked. */
+
+ /* Failed to cork the connection.
+ * Really unlikely to happen on TCP connections. */
+#endif /* MHD_TCP_CORK_NOPUSH */
+ if (_MHD_OFF == connection->sk_nodelay)
+ return; /* TCP_NODELAY was not set for the socket.
+ * Nagle's algorithm will buffer some data. */
+
+ /* Try to reset TCP_NODELAY state for the socket.
+ * Ignore possible error as no other options exist to
+ * buffer data. */
+ connection_set_nodelay_state_ (connection, false);
+ /* TCP_NODELAY has been (hopefully) reset for the socket.
+ * Nagle's algorithm will buffer some data. */
return;
}
- switch (errno)
- {
- case ENOTSOCK:
- /* FIXME: Could be we are talking to a pipe, maybe remember this
- and avoid all setsockopt() in the future? */
- break;
- case EBADF:
- /* FIXME: should we die hard here? */
- break;
- case EINVAL:
- /* FIXME: optlen invalid, should at least log this, maybe die */
-#ifdef HAVE_MESSAGES
- MHD_DLOG (connection->daemon,
- _ ("optlen invalid: %s\n"),
- MHD_socket_last_strerr_ ());
-#endif
- break;
- case EFAULT:
- /* wopsie, should at least log this, FIXME: maybe die */
-#ifdef HAVE_MESSAGES
- MHD_DLOG (connection->daemon,
- _ (
- "The address pointed to by optval is not a valid part of the process address space: %s\n"),
- MHD_socket_last_strerr_ ());
-#endif
- break;
- case ENOPROTOOPT:
- /* optlen unknown, should at least log this */
-#ifdef HAVE_MESSAGES
- MHD_DLOG (connection->daemon,
- _ ("The option is unknown: %s\n"),
- MHD_socket_last_strerr_ ());
-#endif
- break;
- default:
- /* any others? man page does not list more... */
- break;
- }
-#else
- /* CORK/NOPUSH do not exist on this platform,
- Turning on/off of Naggle's algorithm
- (otherwise we keep it always off) */
- if (connection->sk_nodelay == push_data)
+
+ /* Need to push data after send() */
+ /* Prefer to make additional sys-call after the send()
+ * as the next send() may consume only part of the
+ * prepared data and additional send() may be required. */
+#ifdef MHD_TCP_CORK_NOPUSH
+#ifdef _MHD_CORK_RESET_PUSH_DATA
+#ifdef _MHD_CORK_RESET_PUSH_DATA_ALWAYS
+ /* Data can be pushed immediately by uncorking socket regardless of
+ * cork state before. */
+ /* This is typical for Linux, no other kernel with
+ * such behavior are known so far. */
+
+ /* No need to check the current state of TCP_CORK / TCP_NOPUSH
+ * as reset of cork will push the data anyway. */
+ return; /* Data may be pushed by resetting of
+ * TCP_CORK / TCP_NOPUSH after send() */
+#else /* ! _MHD_CORK_RESET_PUSH_DATA_ALWAYS */
+ /* Reset of TCP_CORK / TCP_NOPUSH will push the data
+ * only if socket is corked. */
+
+#ifdef _MHD_NODELAY_SET_PUSH_DATA_ALWAYS
+ /* Data can be pushed immediately by setting TCP_NODELAY regardless
+ * of TCP_NODDELAY or corking state before. */
+
+ /* Dead code currently, no known kernels with such behavior. */
+ return; /* Data may be pushed by setting of TCP_NODELAY after send().
+ No need to make extra sys-calls before send().*/
+#else /* ! _MHD_NODELAY_SET_PUSH_DATA_ALWAYS */
+
+#ifdef _MHD_NODELAY_SET_PUSH_DATA
+ /* Setting of TCP_NODELAY will push the data only if
+ * both TCP_NODELAY and TCP_CORK / TCP_NOPUSH were not set. */
+
+ /* Data can be pushed immediately by uncorking socket if
+ * socket was corked before or by setting TCP_NODELAY if
+ * socket was not corked and TCP_NODELAY was not set before. */
+
+ /* Dead code currently as Linux is the only kernel that push
+ * data by setting of TCP_NODELAY and Linux push data always. */
+#else /* ! _MHD_NODELAY_SET_PUSH_DATA */
+ /* Data can be pushed immediately by uncorking socket or
+ * can be pushed by send() on uncorked socket if
+ * TCP_NODELAY was set *before*. */
+
+ /* This is typical FreeBSD behavior. */
+#endif /* ! _MHD_NODELAY_SET_PUSH_DATA */
+
+ if (_MHD_ON == connection->sk_corked)
+ return; /* Socket is corked. Data can be pushed by resetting of
+ * TCP_CORK / TCP_NOPUSH after send() */
+ else if (_MHD_OFF == connection->sk_corked)
{
- /* nothing to do, success! */
- return;
+ /* The socket is not corked. */
+ if (_MHD_ON == connection->sk_nodelay)
+ return; /* TCP_NODELAY was already set,
+ * data will be pushed automatically by the next send() */
+#ifdef _MHD_NODELAY_SET_PUSH_DATA
+ else if (_MHD_UNKNOWN == connection->sk_nodelay)
+ {
+ /* Setting TCP_NODELAY may push data.
+ * Cork socket here and uncork after send(). */
+ if (connection_set_cork_state_ (connection, true))
+ return; /* The connection has been corked.
+ * Data can be pushed by resetting of
+ * TCP_CORK / TCP_NOPUSH after send() */
+ else
+ {
+ /* The socket cannot be corked.
+ * Really unlikely to happen on TCP connections */
+ /* Have to set TCP_NODELAY.
+ * If TCP_NODELAY real system state was OFF then
+ * already buffered data may be pushed here, but this is unlikely
+ * to happen as it is only a backup solution when corking has failed.
+ * Ignore possible error here as no other options exist to
+ * push data. */
+ connection_set_nodelay_state_ (connection, true);
+ /* TCP_NODELAY has been (hopefully) set for the socket.
+ * The data will be pushed by the next send(). */
+ return;
+ }
+ }
+#endif /* _MHD_NODELAY_SET_PUSH_DATA */
+ else
+ {
+#ifdef _MHD_NODELAY_SET_PUSH_DATA
+ /* TCP_NODELAY was switched off and
+ * the socket is not corked. */
+#else /* ! _MHD_NODELAY_SET_PUSH_DATA */
+ /* Socket is not corked and TCP_NODELAY was not set or unknown. */
+#endif /* ! _MHD_NODELAY_SET_PUSH_DATA */
+
+ /* At least one additional sys-call is required. */
+ /* Setting TCP_NODELAY is optimal here as data will be pushed
+ * automatically by the next send() and no additional
+ * sys-call are needed after the send(). */
+ if (connection_set_nodelay_state_ (connection, true))
+ return;
+ else
+ {
+ /* Failed to set TCP_NODELAY for the socket.
+ * Really unlikely to happen on TCP connections. */
+ /* Cork the socket here and make additional sys-call
+ * to uncork the socket after send(). */
+ /* Ignore possible error here as no other options exist to
+ * push data. */
+ connection_set_cork_state_ (connection, true);
+ /* The connection has been (hopefully) corked.
+ * Data can be pushed by resetting of TCP_CORK / TCP_NOPUSH
+ * after send() */
+ return;
+ }
+ }
}
- if (0 == MHD_socket_set_nodelay_ (connection->socket_fd,
- (push_data)))
- connection->sk_nodelay = push_data;
-#endif
+ /* Corked state is unknown. Need to make sys-call here otherwise
+ * data may not be pushed. */
+ if (connection_set_cork_state_ (connection, true))
+ return; /* The connection has been corked.
+ * Data can be pushed by resetting of
+ * TCP_CORK / TCP_NOPUSH after send() */
+ /* The socket cannot be corked.
+ * Really unlikely to happen on TCP connections */
+ if (_MHD_ON == connection->sk_nodelay)
+ return; /* TCP_NODELAY was already set,
+ * data will be pushed by the next send() */
+ /* Have to set TCP_NODELAY. */
+#ifdef _MHD_NODELAY_SET_PUSH_DATA
+ /* If TCP_NODELAY state was unknown (external connection) then
+ * already buffered data may be pushed here, but this is unlikely
+ * to happen as it is only a backup solution when corking has failed. */
+#endif /* _MHD_NODELAY_SET_PUSH_DATA */
+ /* Ignore possible error here as no other options exist to
+ * push data. */
+ connection_set_nodelay_state_ (connection, true);
+ /* TCP_NODELAY has been (hopefully) set for the socket.
+ * The data will be pushed by the next send(). */
+ return;
+#endif /* ! _MHD_NODELAY_SET_PUSH_DATA_ALWAYS */
+#endif /* ! _MHD_CORK_RESET_PUSH_DATA_ALWAYS */
+#else /* ! _MHD_CORK_RESET_PUSH_DATA */
+ /* Neither uncorking the socket or setting TCP_NODELAY
+ * push the data immediately. */
+ /* The only way to push the data is to use send() on uncorked
+ * socket with TCP_NODELAY switched on . */
+
+ /* This is a typical *BSD (except FreeBSD) and Darwin behavior. */
+
+ /* Uncork socket if socket wasn't uncorked. */
+ if (_MHD_OFF != connection->sk_corked)
+ connection_set_cork_state_ (connection, false);
+
+ /* Set TCP_NODELAY if it wasn't set. */
+ if (_MHD_ON != connection->sk_nodelay)
+ connection_set_nodelay_state_ (connection, true);
+
+ return;
+#endif /* ! _MHD_CORK_RESET_PUSH_DATA */
+#else /* ! MHD_TCP_CORK_NOPUSH */
+ /* Buffering of data is controlled only by
+ * Nagel's algorithm. */
+ /* Set TCP_NODELAY if it wasn't set. */
+ if (_MHD_ON != connection->sk_nodelay)
+ connection_set_nodelay_state_ (connection, true);
+#endif /* ! MHD_TCP_CORK_NOPUSH */
+}
+
+
+#ifndef _MHD_CORK_RESET_PUSH_DATA_ALWAYS
+/**
+ * Send zero-sized data
+ *
+ * This function use send of zero-sized data to kick data from the socket
+ * buffers to the network. The socket must not be corked and must have
+ * TCP_NODELAY switched on.
+ * Used only as last resort option, when other options are failed due to
+ * some errors.
+ * Should not be called on typical data processing.
+ * @return true if succeed, false if failed
+ */
+static bool
+zero_send_ (struct MHD_Connection *connection)
+{
+ int dummy;
+ mhd_assert (_MHD_OFF == connection->sk_corked);
+ mhd_assert (_MHD_ON == connection->sk_nodelay);
+
+ dummy = 0; /* Mute compiler and analyzer warnings */
+
+ if (0 == MHD_send_ (connection->socket_fd, &dummy, 0))
+ return true;
+
+#ifdef HAVE_MESSAGES
+ MHD_DLOG (connection->daemon,
+ _ ("Zero-send failed: %s\n"),
+ MHD_socket_last_strerr_ () );
+#endif /* HAVE_MESSAGES */
+ return false;
}
+#endif /* ! _MHD_CORK_RESET_PUSH_DATA_ALWAYS */
+
/**
* Handle post-send setsockopt calls.
*
* @param connection the MHD_Connection structure
- * @param plain_send set to true if plain send() or sendmsg() have been
- * called,
- * set to false if TLS socket send(), sendfile() or
- * writev() has been called.
+ * @param plain_send_next set to true if plain send() or sendmsg() will be
+ * called next,
+ * set to false if TLS socket send(), sendfile() or
+ * writev() will be called next.
* @param push_data whether to push data to the network from buffers
*/
static void
post_send_setopt (struct MHD_Connection *connection,
- bool plain_send,
+ bool plain_send_next,
bool push_data)
{
int ret;
@@ -223,70 +500,163 @@ post_send_setopt (struct MHD_Connection *connection,
* Final piece is indicated by push_data == true. */
const bool buffer_data = (! push_data);
+ if (buffer_data)
+ return; /* Nothing to do after send(). */
+
+#ifndef MHD_USE_MSG_MORE
+ (void) plain_send_next; /* Mute compiler warning */
+#endif /* ! MHD_USE_MSG_MORE */
+
+ /* Need to push data. */
+#ifdef MHD_TCP_CORK_NOPUSH
+#ifdef _MHD_CORK_RESET_PUSH_DATA_ALWAYS
+#ifdef _MHD_NODELAY_SET_PUSH_DATA_ALWAYS
#ifdef MHD_USE_MSG_MORE
- if (plain_send)
+ if (_MHD_OFF == connection->sk_corked)
{
- /* MSG_MORE is used, no need for extra syscalls! */
- return;
+ if (_MHD_ON == connection->sk_nodelay)
+ return; /* Data was already pushed by send(). */
+ }
+ /* This is Linux kernel. There are options:
+ * * Push the data by setting of TCP_NODELAY (without change
+ * of the cork on the socket),
+ * * Push the data by resetting of TCP_CORK.
+ * The optimal choice depends on the next final send functions
+ * used on the same socket. If TCP_NODELAY wasn't set then push
+ * data by setting TCP_NODELAY (TCP_NODELAY will not be removed
+ * and is needed to push the data by send() without MSG_MORE).
+ * If send()/sendmsg() will be used next than push data by
+ * reseting of TCP_CORK so next send without MSG_MORE will push
+ * data to the network (without additional sys-call to push data).
+ * If next final send function will not support MSG_MORE (like
+ * sendfile() or TLS-connection) than push data by setting
+ * TCP_NODELAY so socket will remain corked (no additional
+ * sys-call before next send()). */
+ if ((_MHD_ON != connection->sk_nodelay) ||
+ (! plain_send_next))
+ {
+ if (connection_set_nodelay_state_ (connection, true))
+ return; /* Data has been pushed by TCP_NODELAY. */
+ /* Failed to set TCP_NODELAY for the socket.
+ * Really unlikely to happen on TCP connections. */
+ if (connection_set_cork_state_ (connection, false))
+ return; /* Data has been pushed by uncorking the socket. */
+ /* Failed to uncork the socket.
+ * Really unlikely to happen on TCP connections. */
+
+ /* The socket cannot be uncorked, no way to push data */
+ }
+ else
+ {
+ if (connection_set_cork_state_ (connection, false))
+ return; /* Data has been pushed by uncorking the socket. */
+ /* Failed to uncork the socket.
+ * Really unlikely to happen on TCP connections. */
+ if (connection_set_nodelay_state_ (connection, true))
+ return; /* Data has been pushed by TCP_NODELAY. */
+ /* Failed to set TCP_NODELAY for the socket.
+ * Really unlikely to happen on TCP connections. */
+
+ /* The socket cannot be uncorked, no way to push data */
}
#else /* ! MHD_USE_MSG_MORE */
- (void) plain_send; /* Mute compiler warning. */
+ /* Use setting of TCP_NODELAY here to avoid sys-call
+ * for corking the socket during sending of the next response. */
+ if (connection_set_nodelay_state_ (connection, true))
+ return; /* Data was pushed by TCP_NODELAY. */
+ /* Failed to set TCP_NODELAY for the socket.
+ * Really unlikely to happen on TCP connections. */
+ if (connection_set_cork_state_ (connection, false))
+ return; /* Data was pushed by uncorking the socket. */
+ /* Failed to uncork the socket.
+ * Really unlikely to happen on TCP connections. */
+
+ /* The socket remains corked, no way to push data */
#endif /* ! MHD_USE_MSG_MORE */
+#else /* ! _MHD_NODELAY_SET_PUSH_DATA_ALWAYS */
+ if (connection_set_cork_state_ (connection, false))
+ return; /* Data was pushed by uncorking the socket. */
+ /* Failed to uncork the socket.
+ * Really unlikely to happen on TCP connections. */
+ return; /* Socket remains corked, no way to push data */
+#endif /* ! _MHD_NODELAY_SET_PUSH_DATA_ALWAYS */
+#else /* ! _MHD_CORK_RESET_PUSH_DATA_ALWAYS */
+ /* This is a typical *BSD or Darwin kernel. */
-#if defined(MHD_TCP_CORK_NOPUSH)
- /* If connection is already in required corked state, do nothing. */
- if (connection->sk_corked == buffer_data)
- return;
- if (buffer_data)
- return; /* nothing to do *post* syscall (in fact, we should never
- get here, as sk_corked should have succeeded in the
- pre-syscall) */
- ret = MHD_socket_cork_ (connection->socket_fd,
- buffer_data);
- if (0 != ret)
+ if (_MHD_OFF == connection->sk_corked)
{
- connection->sk_corked = buffer_data;
- return;
+ if (_MHD_ON == connection->sk_nodelay)
+ return; /* Data was already pushed by send(). */
+
+ /* Unlikely to reach this code.
+ * TCP_NODELAY should be turned on before send(). */
+ if (connection_set_nodelay_state_ (connection, true))
+ {
+ /* TCP_NODELAY has been set on uncorked socket.
+ * Use zero-send to push the data. */
+ if (zero_send_ (connection))
+ return; /* The data has been pushed by zero-send. */
+ }
+
+ /* Failed to push the data by all means. */
+ /* There is nothing left to try. */
}
- switch (errno)
+ else
{
- case ENOTSOCK:
- /* FIXME: Could be we are talking to a pipe, maybe remember this
- and avoid all setsockopt() in the future? */
- break;
- case EBADF:
- /* FIXME: should we die hard here? */
- break;
- case EINVAL:
- /* FIXME: optlen invalid, should at least log this, maybe die */
-#ifdef HAVE_MESSAGES
- MHD_DLOG (connection->daemon,
- _ ("optlen invalid: %s\n"),
- MHD_socket_last_strerr_ ());
-#endif
- break;
- case EFAULT:
- /* wopsie, should at least log this, FIXME: maybe die */
-#ifdef HAVE_MESSAGES
- MHD_DLOG (connection->daemon,
- _ (
- "The address pointed to by optval is not a valid part of the process address space: %s\n"),
- MHD_socket_last_strerr_ ());
-#endif
- break;
- case ENOPROTOOPT:
- /* optlen unknown, should at least log this */
-#ifdef HAVE_MESSAGES
- MHD_DLOG (connection->daemon,
- _ ("The option is unknown: %s\n"),
- MHD_socket_last_strerr_ ());
-#endif
- break;
- default:
- /* any others? man page does not list more... */
- break;
+#ifdef _MHD_CORK_RESET_PUSH_DATA
+ enum MHD_tristate old_cork_state = connection->sk_corked;
+#endif /* _MHD_CORK_RESET_PUSH_DATA */
+ /* The socket is corked or cork state is unknown. */
+
+ if (connection_set_cork_state_ (connection, false))
+ {
+#ifdef _MHD_CORK_RESET_PUSH_DATA
+ /* FreeBSD kernel */
+ if (_MHD_OFF == old_cork_state)
+ return; /* Data has been pushed by uncorking the socket. */
+#endif /* _MHD_CORK_RESET_PUSH_DATA */
+
+ /* Unlikely to reach this code.
+ * The data should be pushed by uncorking (FreeBSD) or
+ * the socket should be uncorked before send(). */
+ if ((_MHD_ON == connection->sk_nodelay) ||
+ (connection_set_nodelay_state_ (connection, true)))
+ {
+ /* TCP_NODELAY is turned ON on uncorked socket.
+ * Use zero-send to push the data. */
+ if (zero_send_ (connection))
+ return; /* The data has been pushed by zero-send. */
+ }
+ }
+ /* The socket remains corked. Data cannot be pushed. */
}
-#endif
+#endif /* ! _MHD_CORK_RESET_PUSH_DATA_ALWAYS */
+#else /* ! MHD_TCP_CORK_NOPUSH */
+ /* Corking is not supported. Buffering is controlled
+ * by TCP_NODELAY only. */
+ mhd_assert (_MHD_ON != connection->sk_corked);
+ if (_MHD_ON == connection->sk_nodelay)
+ return; /* Data was already pushed by send(). */
+
+ /* Unlikely to reach this code.
+ * TCP_NODELAY should be turned on before send(). */
+ if (connection_set_nodelay_state_ (connection, true))
+ {
+ /* TCP_NODELAY has been set.
+ * Use zero-send to push the data. */
+ if (zero_send_ (connection))
+ return; /* The data has been pushed by zero-send. */
+ }
+
+ /* Failed to push the data. */
+#endif /* ! MHD_TCP_CORK_NOPUSH */
+#ifdef HAVE_MESSAGES
+ MHD_DLOG (connection->daemon,
+ _ ("Failed to put the data from buffers to the network. "
+ "Client may experience some delay "
+ "(usually in range 200ms - 5 sec).\n"));
+#endif /* HAVE_MESSAGES */
+ return;
}
@@ -422,8 +792,16 @@ MHD_send_on_connection_ (struct MHD_Connection *connection,
connection->epoll_state &= ~MHD_EPOLL_STATE_WRITE_READY;
#endif /* EPOLL_SUPPORT */
}
- post_send_setopt (connection, tls_conn,
- (push_data && (buffer_size == (size_t) ret)) );
+
+ /* If there is a need to push the data from network buffers
+ * call post_send_setopt(). */
+ /* If TLS connection is used then next final send() will be
+ * without MSG_MORE support. If non-TLS connection is used
+ * it's unknown whether sendfile() will be used or not so
+ * assume that next call will be the same, like this call. */
+ if ( (push_data) &&
+ (buffer_size == (size_t) ret) )
+ post_send_setopt (connection, (! tls_conn), push_data);
return ret;
}
@@ -455,7 +833,9 @@ MHD_send_on_connection2_ (struct MHD_Connection *connection,
{
MHD_socket s = connection->socket_fd;
ssize_t ret;
+#if defined(HAVE_SENDMSG) || defined(HAVE_WRITEV)
struct iovec vector[2];
+#endif /* HAVE_SENDMSG || HAVE_WRITEV */
#ifdef HTTPS_SUPPORT
const bool tls_conn = (connection->daemon->options & MHD_USE_TLS);
#else /* ! HTTPS_SUPPORT */
@@ -477,7 +857,13 @@ MHD_send_on_connection2_ (struct MHD_Connection *connection,
#if defined(HAVE_SENDMSG) || defined(HAVE_WRITEV)
/* Since we generally give the fully answer, we do not want
corking to happen */
- pre_send_setopt (connection, (! tls_conn), true);
+ pre_send_setopt (connection,
+#if HAVE_SENDMSG
+ true,
+#elif HAVE_WRITEV
+ false,
+#endif /* HAVE_WRITEV */
+ true);
vector[0].iov_base = (void *) header;
vector[0].iov_len = header_size;
@@ -509,10 +895,21 @@ MHD_send_on_connection2_ (struct MHD_Connection *connection,
}
#endif
- /* Only if we succeeded sending the full buffer, we need to make sure that
- the OS flushes at the end */
- post_send_setopt (connection, (! tls_conn),
- (header_size + buffer_size == (size_t) ret));
+ /* If there is a need to push the data from network buffers
+ * call post_send_setopt(). */
+ /* If TLS connection is used then next final send() will be
+ * without MSG_MORE support. If non-TLS connection is used
+ * it's unknown whether sendfile() will be used or not so
+ * assume that next final send() will be the same, like for
+ * this response. */
+ if ((header_size + buffer_size) == (size_t) ret)
+ post_send_setopt (connection,
+#if HAVE_SENDMSG
+ true,
+#elif HAVE_WRITEV
+ false,
+#endif /* HAVE_WRITEV */
+ true);
return ret;
@@ -563,22 +960,36 @@ MHD_send_sendfile_ (struct MHD_Connection *connection)
const size_t chunk_size = used_thr_p_c ? MHD_SENFILE_CHUNK_THR_P_C_ :
MHD_SENFILE_CHUNK_;
size_t send_size = 0;
+ bool push_data;
mhd_assert (MHD_resp_sender_sendfile == connection->resp_sender);
mhd_assert (0 == (connection->daemon->options & MHD_USE_TLS));
- pre_send_setopt (connection, false, true);
-
offsetu64 = connection->response_write_position
+ connection->response->fd_off;
- left = connection->response->total_size - connection->response_write_position;
- /* Do not allow system to stick sending on single fast connection:
- * use 128KiB chunks (2MiB for thread-per-connection). */
- send_size = (left > chunk_size) ? chunk_size : (size_t) left;
if (max_off_t < offsetu64)
{ /* Retry to send with standard 'send()'. */
connection->resp_sender = MHD_resp_sender_std;
return MHD_ERR_AGAIN_;
}
+
+ left = connection->response->total_size - connection->response_write_position;
+
+ if ( (uint64_t) SSIZE_MAX > left)
+ left = SSIZE_MAX;
+ /* Do not allow system to stick sending on single fast connection:
+ * use 128KiB chunks (2MiB for thread-per-connection). */
+ if (chunk_size < left)
+ {
+ send_size = chunk_size;
+ push_data = false; /* No need to push data, there is more to send, */
+ }
+ else
+ {
+ send_size = (size_t) left;
+ push_data = true; /* Final piece of data, need to push to the network. */
+ }
+ pre_send_setopt (connection, false, push_data);
+
#ifdef MHD_LINUX_SOLARIS_SENDFILE
#ifndef HAVE_SENDFILE64
offset = (off_t) offsetu64;
@@ -708,9 +1119,13 @@ MHD_send_sendfile_ (struct MHD_Connection *connection)
ret = (ssize_t) len;
#endif /* HAVE_FREEBSD_SENDFILE */
- /* Make sure we send the data without delay ONLY if we
- provided the complete response (not on partial write) */
- post_send_setopt (connection, false, (left == (uint64_t) ret));
+ /* If there is a need to push the data from network buffers
+ * call post_send_setopt(). */
+ /* It's unknown whether sendfile() will be used in the next
+ * response so assume that next response will be the same. */
+ if ( (push_data) &&
+ (send_size == (size_t) ret) )
+ post_send_setopt (connection, false, push_data);
return ret;
}
diff --git a/src/microhttpd/mhd_send.h b/src/microhttpd/mhd_send.h
@@ -1,6 +1,7 @@
/*
This file is part of libmicrohttpd
Copyright (C) 2019 ng0
+ Copyright (C) 2017 Karlson2k (Evgeny Grin)
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
@@ -20,8 +21,9 @@
/**
* @file mhd_send.h
- * @brief Implementation of send() wrappers.
+ * @brief Declarations of send() wrappers.
* @author ng0
+ * @author Karlson2k (Evgeny Grin)
*/
#ifndef MHD_SEND_H
