diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/xs.txt | 63 | ||||
| -rw-r--r-- | doc/xs_init.txt | 23 | ||||
| -rw-r--r-- | doc/xs_poll.txt | 2 | ||||
| -rw-r--r-- | doc/xs_recv.txt | 32 | ||||
| -rw-r--r-- | doc/xs_recvmsg.txt | 16 | ||||
| -rw-r--r-- | doc/xs_send.txt | 23 | ||||
| -rw-r--r-- | doc/xs_sendmsg.txt | 13 | ||||
| -rw-r--r-- | doc/xs_setctxopt.txt | 31 | ||||
| -rw-r--r-- | doc/xs_zmq.txt | 2 |
9 files changed, 132 insertions, 73 deletions
@@ -48,18 +48,25 @@ Initialise Crossroads context:: Terminate Crossroads context:: linkxs:xs_term[3] +Set Crossroads context options:: + linkxs:xs_setctxopt[3] + Thread safety ^^^^^^^^^^^^^ A 'context' is thread safe and may be shared among as many application -threads as necessary, without any additional locking required on the part of -the caller. - -Individual Crossroads 'sockets' are _not_ thread safe except in the case where -full memory barriers are issued when migrating a socket from one thread to -another. In practice this means applications can create a socket in one thread -with _xs_socket()_ and then pass it to a _newly created_ thread as part of -thread initialization, for example via a structure passed as an argument to +threads as necessary, without any additional locking required on the part +of the caller. + +The individual 'sockets' within a 'context' are _not_ thread safe -- +applications may _not_ use a single 'socket' concurrently from multiple +threads. + +A 'socket' _may_ be _migrated_ from one thread to another, by issuing a +full memory barrier between individual calls on the 'socket'. For example, +this means applications can create a socket in one thread with +_xs_socket()_ and then pass it to a _newly created_ thread as part of +thread initialization via a structure passed as an argument to _pthread_create()_. @@ -68,18 +75,28 @@ Multiple contexts Multiple 'contexts' may coexist within a single application. Thus, an application can use Crossroads directly and at the same time make use of any number of additional libraries or components which themselves make use of -Crossroads as long as the above guidelines regarding thread safety are adhered -to. +Crossroads. Messages ~~~~~~~~ -A Crossroads message is a discrete unit of data passed between applications or -components of the same application. Crossroads messages have no internal +A Crossroads message is a discrete unit of data passed between applications +or components of the same application. Crossroads messages have no internal structure and from the point of view of Crossroads themselves they are considered to be opaque binary data. -The following functions are provided to work with messages: +Applications using the Crossroads library send and receive messages +directly from/to buffers provided by the application, using the Crossroads +functions _xs_send()_ and _xs_recv()_. + +Alternatively, applications desiring zero-copy messaging and/or reference +counted allocation of messages can use the message handling functions +described in this section, and send and receive messages using +_xs_sendmsg()_ and _xs_recvmsg()_ respectively. These two approaches are +interchangeable. + +The following functions are provided to work with messages using zero-copy +and/or reference-counted allocation of messages: Initialise a message:: linkxs:xs_msg_init[3] @@ -97,6 +114,9 @@ Message manipulation:: linkxs:xs_msg_copy[3] linkxs:xs_msg_move[3] +Retrieve message option:: + linkxs:xs_getmsgopt[3] + Sockets ~~~~~~~ @@ -124,8 +144,12 @@ Sending and receiving messages:: linkxs:xs_send[3] linkxs:xs_recv[3] +Sending and receiving messages (zero-copy):: + linkxs:xs_sendmsg[3] + linkxs:xs_recvmsg[3] + .Input/output multiplexing -Crossroads provide a mechanism for applications to multiplex input/output events +Crossroads provides a mechanism for applications to multiplex input/output events over a set containing both Crossroads sockets and standard sockets. This mechanism mirrors the standard _poll()_ system call, and is described in detail in linkxs:xs_poll[3]. @@ -151,6 +175,7 @@ Local inter-process communication transport:: Local in-process (inter-thread) communication transport:: linkxs:xs_inproc[7] + ERROR HANDLING -------------- The Crossroads library functions handle errors using the standard conventions @@ -199,6 +224,10 @@ and Martin Lucina <martin@lucina.net>. COPYING ------- -Free use of Crossroads library is granted under the terms of the GNU Lesser -General Public License (LGPL). For details see the files `COPYING` and -`COPYING.LESSER` included with the Crossroads distribution. +Free use of the Crossroads library software is granted under the terms of +the GNU Lesser General Public License (LGPL). For details see the files +`COPYING` and `COPYING.LESSER` included with the libxs distribution. + +As a special exception, the copyright holders of libxs grant you the right +to link the library statically with your software. Refer to the end of +the `COPYING.LESSER` file included with the libxs distribution for details. diff --git a/doc/xs_init.txt b/doc/xs_init.txt index 373822a..40a64bf 100644 --- a/doc/xs_init.txt +++ b/doc/xs_init.txt @@ -21,6 +21,28 @@ A 'context' is thread safe and may be shared among as many application threads as necessary, without any additional locking required on the part of the caller. +The individual 'sockets' within a 'context' are _not_ thread safe -- +applications may _not_ use a single 'socket' concurrently from multiple +threads. + +A 'socket' _may_ be _migrated_ from one thread to another, by issuing a +full memory barrier between individual calls on the 'socket'. For example, +this means applications can create a socket in one thread with +_xs_socket()_ and then pass it to a _newly created_ thread as part of +thread initialization via a structure passed as an argument to +_pthread_create()_. + +.Context options +Context options may be set prior to creating the first socket within a +'context', using the _xs_setctxopt()_ function. See linkxs:xs_setctxopt[3] +for details on the available context options. + +.Multiple contexts +Multiple 'contexts' may coexist within a single application. Thus, an +application can use Crossroads directly and at the same time make use of any +number of additional libraries or components which themselves make use of +Crossroads. + RETURN VALUE ------------ @@ -38,6 +60,7 @@ SEE ALSO -------- linkxs:xs[7] linkxs:xs_term[3] +linkxs:xs_setctxopt[3] AUTHORS diff --git a/doc/xs_poll.txt b/doc/xs_poll.txt index 37f7dc5..c809e28 100644 --- a/doc/xs_poll.txt +++ b/doc/xs_poll.txt @@ -10,7 +10,7 @@ xs_poll - input/output multiplexing SYNOPSIS -------- -*int xs_poll (xs_pollitem_t '*items', int 'nitems', long 'timeout');* +*int xs_poll (xs_pollitem_t '*items', int 'nitems', int 'timeout');* DESCRIPTION diff --git a/doc/xs_recv.txt b/doc/xs_recv.txt index 26a6c54..5706432 100644 --- a/doc/xs_recv.txt +++ b/doc/xs_recv.txt @@ -29,22 +29,22 @@ function shall fail with 'errno' set to EAGAIN. Multi-part messages ~~~~~~~~~~~~~~~~~~~ -A Crossroads message is composed of 1 or more message parts. Each message -part is an independent 'xs_msg_t' in its own right. Crossroads ensure atomic -delivery of messages; peers shall receive either all _message parts_ of a -message or none at all. The total number of message parts is unlimited except -by available memory. +A Crossroads message is composed of 1 or more message parts. Crossroads +ensures atomic delivery of messages; peers shall receive either all +_message parts_ of a message or none at all. The total number of message +parts is unlimited except by available memory. An application that processes multipart messages must use the _XS_RCVMORE_ -linkxs:xs_getsockopt[3] option after calling _xs_recv()_ to determine if -there are further parts to receive. +linkxs:xs_getsockopt[3] option on the 'socket' after calling _xs_recv()_ to +determine if there are further parts to receive. RETURN VALUE ------------ -The _xs_recv()_ function shall return number of bytes in the message -if successful. Note that the value can exceed the value of the 'len' parameter -in case the message was truncated. If not successful the function shall return -`-1` and set 'errno' to one of the values defined below. +The _xs_recv()_ function shall return the number of bytes in the received +message if successful. Note that the value can exceed the value of the +'len' parameter, in this case the message was truncated. If not successful +the function shall return `-1` and set 'errno' to one of the values defined +below. ERRORS @@ -79,8 +79,9 @@ assert (nbytes != -1); SEE ALSO -------- -linkxs:xs_recvmsg[3] -linkxs:xs_send[3] +Applications that wish to use zero-copy messaging must use +linkxs:xs_recvmsg[3] instead of _xs_recv()_. + linkxs:xs_sendmsg[3] linkxs:xs_getsockopt[3] linkxs:xs_socket[7] @@ -89,6 +90,5 @@ linkxs:xs[7] AUTHORS ------- -+This man page was written by Martin Sustrik <sustrik@250bpm.com>, Martin -+Lucina <martin@lucina.net> and Pieter Hintjens <ph@imatix.com>. - +This man page was written by Martin Sustrik <sustrik@250bpm.com>, Martin +Lucina <martin@lucina.net> and Pieter Hintjens <ph@imatix.com>. diff --git a/doc/xs_recvmsg.txt b/doc/xs_recvmsg.txt index 735fed0..4a88177 100644 --- a/doc/xs_recvmsg.txt +++ b/doc/xs_recvmsg.txt @@ -4,7 +4,7 @@ xs_recvmsg(3) NAME ---- -xs_recvmsg - receive a message part from a socket +xs_recvmsg - receive a message part from a socket (zero-copy) SYNOPSIS @@ -30,7 +30,7 @@ function shall fail with 'errno' set to EAGAIN. Multi-part messages ~~~~~~~~~~~~~~~~~~~ A Crossroads message is composed of 1 or more message parts. Each message -part is an independent 'xs_msg_t' in its own right. Crossroads ensure atomic +part is an independent 'xs_msg_t' in its own right. Crossroads ensures atomic delivery of messages; peers shall receive either all _message parts_ of a message or none at all. The total number of message parts is unlimited except by available memory. @@ -42,9 +42,9 @@ there are further parts to receive. RETURN VALUE ------------ -The _xs_recvmsg()_ function shall return number of bytes in the message -if successful. Otherwise it shall return `-1` and set 'errno' to one of the -values defined below. +The _xs_recvmsg()_ function shall return the number of bytes in the +received message if successful. Otherwise it shall return `-1` and set +'errno' to one of the values defined below. ERRORS @@ -106,8 +106,9 @@ do { SEE ALSO -------- -linkxs:xs_recv[3] -linkxs:xs_send[3] +Applications that do not require zero-copy messaging can use the simpler +linkxs:xs_recv[3] instead of _xs_recvmsg()_. + linkxs:xs_sendmsg[3] linkxs:xs_getsockopt[3] linkxs:xs_socket[7] @@ -118,4 +119,3 @@ AUTHORS ------- This man page was written by Martin Sustrik <sustrik@250bpm.com>, Martin Lucina <martin@lucina.net> and Pieter Hintjens <ph@imatix.com>. - diff --git a/doc/xs_send.txt b/doc/xs_send.txt index f2d66e4..72bbf88 100644 --- a/doc/xs_send.txt +++ b/doc/xs_send.txt @@ -4,7 +4,7 @@ xs_send(3) NAME ---- -xs_send - send a message part on a socket +xs_send - send a message part on a socket SYNOPSIS @@ -35,14 +35,13 @@ the 'socket' and Crossroads have assumed responsibility for the message. Multi-part messages ~~~~~~~~~~~~~~~~~~~ -A Crossroads message is composed of 1 or more message parts. Each message -part is an independent 'xs_msg_t' in its own right. Crossroads ensure atomic -delivery of messages; peers shall receive either all _message parts_ of a -message or none at all. The total number of message parts is unlimited except -by available memory. +A Crossroads message is composed of 1 or more message parts. Crossroads +ensures atomic delivery of messages; peers shall receive either all +_message parts_ of a message or none at all. The total number of message +parts is unlimited except by available memory. An application that sends multipart messages must use the _XS_SNDMORE_ flag -when sending each data part except the final one. +when sending each message part except the final one. RETURN VALUE @@ -88,15 +87,15 @@ assert (rc == 2); SEE ALSO -------- -linkxs:xs_sendmsg[3] +Applications that wish to use zero-copy messaging must use +linkxs:xs_sendmsg[3] instead of _xs_send()_. + linkxs:xs_recv[3] -linkxs:xs_recvmsg[3] linkxs:xs_socket[7] linkxs:xs[7] AUTHORS ------- -+This man page was written by Martin Sustrik <sustrik@250bpm.com>, Martin -+Lucina <martin@lucina.net> and Pieter Hintjens <ph@imatix.com>. - +This man page was written by Martin Sustrik <sustrik@250bpm.com>, Martin +Lucina <martin@lucina.net> and Pieter Hintjens <ph@imatix.com>. diff --git a/doc/xs_sendmsg.txt b/doc/xs_sendmsg.txt index 9478b4a..7445f25 100644 --- a/doc/xs_sendmsg.txt +++ b/doc/xs_sendmsg.txt @@ -4,7 +4,7 @@ xs_sendmsg(3) NAME ---- -xs_sendmsg - send a message part on a socket +xs_sendmsg - send a message part on a socket (zero-copy) SYNOPSIS @@ -48,6 +48,7 @@ by available memory. An application that sends multipart messages must use the _XS_SNDMORE_ flag when sending each data part except the final one. + RETURN VALUE ------------ The _xs_sendmsg()_ function shall return number of bytes in the message @@ -104,8 +105,9 @@ rc = xs_sendmsg (socket, &part3, 0); SEE ALSO -------- -linkxs:xs_recv[3] -linkxs:xs_recv[3] +Applications that do not require zero-copy messaging can use the simpler +linkxs:xs_send[3] instead of _xs_sendmsg()_. + linkxs:xs_recvmsg[3] linkxs:xs_socket[7] linkxs:xs[7] @@ -113,6 +115,5 @@ linkxs:xs[7] AUTHORS ------- -+This man page was written by Martin Sustrik <sustrik@250bpm.com>, Martin -+Lucina <martin@lucina.net> and Pieter Hintjens <ph@imatix.com>. - +This man page was written by Martin Sustrik <sustrik@250bpm.com>, Martin +Lucina <martin@lucina.net> and Pieter Hintjens <ph@imatix.com>. diff --git a/doc/xs_setctxopt.txt b/doc/xs_setctxopt.txt index d26d319..ccdd2db 100644 --- a/doc/xs_setctxopt.txt +++ b/doc/xs_setctxopt.txt @@ -12,22 +12,24 @@ SYNOPSIS -------- *int xs_setctxopt (void '*context', int 'option_name', const void '*option_value', size_t 'option_len');* -Caution: All options take effect only if set prior to creating the first socket. DESCRIPTION ----------- The _xs_setctxopt()_ function shall set the option specified by the -'option_name' argument to the value pointed to by the 'option_value' argument -for the Crossroads context pointed to by the 'context' argument. +'option_name' argument to the value pointed to by the 'option_value' +argument, for the Crossroads context pointed to by the 'context' argument. The 'option_len' argument is the size of the option value in bytes. +CAUTION: Context options take effect only if set with _xs_setctxopt()_ +prior to creating the first socket in a given 'context' with _xs_socket()_. + The following options can be set with the _xs_setctxopt()_ function: XS_MAX_SOCKETS: Set maximum number of sockets ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -The 'XS_MAX_SOCKETS' option shall set specify the maximum nuber of sockets -that can be open at the same time. +The 'XS_MAX_SOCKETS' option shall set the maximum nuber of sockets that can +be simultaneously active in the given 'context'. [horizontal] Option value type:: int @@ -36,8 +38,9 @@ Default value:: 512 XS_IO_THREADS: Set number of worker threads ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -The 'XS_IO_THREADS' option shall set specify the size of the thread pool to -handle I/O operations. The value should be at least 1. +The 'XS_IO_THREADS' option shall set the size of the thread pool created by +the given 'context' to handle I/O operations. The minimum value for this +option is `1`. [horizontal] Option value type:: int @@ -60,21 +63,23 @@ The provided 'context' was invalid. EXAMPLE ------- -.Setting maximal number of sockets to three. +.Setting the number of I/O threads for a context to four. ---- -int val = 3; -rc = xs_setctxopt (context, XS_CTX_MAX_SOCKETS, &val, sizeof (val)); +void *context = xs_init (); +int io_threads = 4; +rc = xs_setctxopt (context, XS_IO_THREADS, &io_threads, sizeof (io_threads)); assert (rc == 0); +/* The above call MUST be called before any socket is created in context */ +void *socket = xs_socket (context, XS_PUB); ---- SEE ALSO -------- -linkxs:xs_getsockopt[3] -linkxs:xs_setsockopt[3] linkxs:xs_init[3] linkxs:xs[7] AUTHORS ------- -This manual page was written by Martin Sustrik <sustrik@250bpm.com>. +The Crossroads documentation was written by Martin Sustrik <sustrik@250bpm.com> +and Martin Lucina <martin@lucina.net>. diff --git a/doc/xs_zmq.txt b/doc/xs_zmq.txt index 310ab64..570ef5e 100644 --- a/doc/xs_zmq.txt +++ b/doc/xs_zmq.txt @@ -72,6 +72,8 @@ Messages *int zmq_msg_init (zmq_msg_t '*msg');* *int zmq_msg_init_size (zmq_msg_t '*msg', size_t 'size');* *int zmq_msg_init_data (zmq_msg_t '*msg', void '*data', size_t 'size', zmq_free_fn '*ffn', void '*hint');* +*size_t zmq_msg_size (zmq_msg_t '*msg');* +*void *zmq_msg_data (zmq_msg_t '*msg');* *int zmq_msg_close (zmq_msg_t '*msg');* *int zmq_msg_copy (zmq_msg_t '*dest', zmq_msg_t '*src');* *int zmq_msg_move (zmq_msg_t '*dest', zmq_msg_t '*src');* |