From 3d675cdbe7287d3024d041ce4e28dacf7ca527cc Mon Sep 17 00:00:00 2001 From: Martin Mares Date: Sat, 3 Jun 2000 14:40:39 +0000 Subject: More documentation. --- nest/cli.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 68 insertions(+), 1 deletion(-) (limited to 'nest/cli.c') diff --git a/nest/cli.c b/nest/cli.c index ec18bc99..c575bfa7 100644 --- a/nest/cli.c +++ b/nest/cli.c @@ -1,11 +1,54 @@ /* * BIRD Internet Routing Daemon -- Command-Line Interface * - * (c) 1999 Martin Mares + * (c) 1999--2000 Martin Mares * * Can be freely distributed and used under the terms of the GNU GPL. */ +/** + * DOC: Command line interface + * + * This module takes care of the BIRD's command-line interface (CLI). + * The CLI exists to provide a way to control BIRD remotely and to inspect + * its status. It uses a very simple textual protocol over a stream + * connection provided by the platform dependent code (on UNIX systems, + * it's a UNIX domain socket). + * + * Each session of the CLI consists of a sequence of request and replies, + * slightly resembling the FTP and SMTP protocols. + * Requests are commands encoded as a single line of text, replies are + * sequences of lines starting with a four-digit code followed by either + * a space (if it's the last line of the reply) or a minus sign (when the + * reply is going to continue with the next line), the rest of the line + * contains a textual message semantics of which depends on the numeric + * code. If a reply line has the same code as the previous one and it's + * a continuation line, the whole prefix can be replaced by a single + * white space character. + * + * Reply codes starting with 0 describe `action successfully completed' messages, + * 1 means `table entry', 8 `runtime error' and 9 `syntax error'. + * + * Each CLI session is internally represented by a &cli structure and a + * resource pool containing all resources associated with the connection, + * so that it can be easily freed whenever the connection closes, not depending + * on the current state of command processing. + * + * The CLI commands are declared as a part of the configuration grammar + * by using the CF_CLI() macro. When a command is received, it's processed + * by the same lexical analyser and parser as used for the configuration, but + * it's switched to a special mode by prepending a fake token to the text, + * so that it uses only the CLI command rules. Then the parser invokes + * an execution routine corresponding to the command, which either constructs + * the whole reply and returns or (in case it expects the reply will be long) + * it prints a partial reply and asks the CLI module (using the @cont hook) + * to call it again when the output will be transferred to the user. + * + * The @this_cli variable points to a &cli structure of the session being + * currently parsed, but it's of course available only in command handlers + * not entered using the @cont hook. + */ + #include "nest/bird.h" #include "nest/cli.h" #include "conf/conf.h" @@ -41,6 +84,24 @@ cli_alloc_out(cli *c, int size) return o->wpos - size; } +/** + * cli_printf - send reply to a CLI connection + * @c: CLI connection + * @code: numeric code of the reply, negative for continuation lines + * @msg: a printf()-like formatting string. + * + * This function send a single line of reply to a given CLI connection. + * In works in all aspects like bsprintf() except that it automatically + * prepends the reply line prefix. + * + * Please note that if the connection can be already busy sending some + * data in which case cli_printf() stores the output to a temporary buffer, + * so please avoid sending a large batch of replies without waiting + * for the buffers to be flushed. + * + * If you want to write to the current CLI output, you can use the cli_msg() + * macro instead. + */ void cli_printf(cli *c, int code, char *msg, ...) { @@ -320,6 +381,12 @@ cli_free(cli *c) rfree(c->pool); } +/** + * cli_init - initialize the CLI module + * + * This function is called during BIRD startup to initialize + * the internal data structures of the CLI module. + */ void cli_init(void) { -- cgit v1.2.3