From patchwork Fri May 17 19:35:44 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnaldo Carvalho de Melo X-Patchwork-Id: 10948523 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 04C021708 for ; Fri, 17 May 2019 19:39:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E546328415 for ; Fri, 17 May 2019 19:39:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D97AD2842B; Fri, 17 May 2019 19:39:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 22F4128434 for ; Fri, 17 May 2019 19:39:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727467AbfEQTjq (ORCPT ); Fri, 17 May 2019 15:39:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:56106 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729566AbfEQTjp (ORCPT ); Fri, 17 May 2019 15:39:45 -0400 Received: from quaco.ghostprotocols.net (unknown [190.15.121.82]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A39C821734; Fri, 17 May 2019 19:39:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558121984; bh=LhFOXG0WISx3V40lhHAcu5eNTbn4/Io60kUmHo1ThfM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wdETtJHxgLB6vhxfrHMeK/ZT+29EC1fKB/U09j7NkeSBDEGh092GxZ16R6sW00ckW IsZzAl9IABZbRxqog82PAqKHi7s6Mrl/hV7wR4+RdOXcb0DUPZFmw8xZoNSwYZ3sAU doZViF0qc9gXe12cj+6Y/ljw7WOpE10foNaTXfyQ= From: Arnaldo Carvalho de Melo To: Ingo Molnar , Thomas Gleixner Cc: Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Tzvetomir Stoyanov , Andrew Morton , Jiri Olsa , linux-trace-devel@vger.kernel.org, Steven Rostedt , Arnaldo Carvalho de Melo Subject: [PATCH 46/73] tools lib traceevent: Man pages for trace sequences APIs Date: Fri, 17 May 2019 16:35:44 -0300 Message-Id: <20190517193611.4974-47-acme@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190517193611.4974-1-acme@kernel.org> References: <20190517193611.4974-1-acme@kernel.org> MIME-Version: 1.0 Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Tzvetomir Stoyanov Create man pages for trace sequences libtraceevent APIs: trace_seq_init(), trace_seq_destroy(), trace_seq_reset(), trace_seq_terminate(), trace_seq_putc(), trace_seq_puts(), trace_seq_printf(), trace_seq_vprintf(), trace_seq_do_fprintf(), trace_seq_do_printf() Signed-off-by: Tzvetomir Stoyanov Cc: Andrew Morton Cc: Jiri Olsa Cc: Namhyung Kim Cc: linux-trace-devel@vger.kernel.org Link: http://lore.kernel.org/linux-trace-devel/20190503091119.23399-27-tstoyanov@vmware.com Link: http://lkml.kernel.org/r/20190510200110.462646052@goodmis.org Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Arnaldo Carvalho de Melo --- .../Documentation/libtraceevent-tseq.txt | 158 ++++++++++++++++++ 1 file changed, 158 insertions(+) create mode 100644 tools/lib/traceevent/Documentation/libtraceevent-tseq.txt diff --git a/tools/lib/traceevent/Documentation/libtraceevent-tseq.txt b/tools/lib/traceevent/Documentation/libtraceevent-tseq.txt new file mode 100644 index 000000000000..8ac6aa174e12 --- /dev/null +++ b/tools/lib/traceevent/Documentation/libtraceevent-tseq.txt @@ -0,0 +1,158 @@ +libtraceevent(3) +================ + +NAME +---- +trace_seq_init, trace_seq_destroy, trace_seq_reset, trace_seq_terminate, +trace_seq_putc, trace_seq_puts, trace_seq_printf, trace_seq_vprintf, +trace_seq_do_fprintf, trace_seq_do_printf - +Initialize / destroy a trace sequence. + +SYNOPSIS +-------- +[verse] +-- +*#include * +*#include * + +void *trace_seq_init*(struct trace_seq pass:[*]_s_); +void *trace_seq_destroy*(struct trace_seq pass:[*]_s_); +void *trace_seq_reset*(struct trace_seq pass:[*]_s_); +void *trace_seq_terminate*(struct trace_seq pass:[*]_s_); +int *trace_seq_putc*(struct trace_seq pass:[*]_s_, unsigned char _c_); +int *trace_seq_puts*(struct trace_seq pass:[*]_s_, const char pass:[*]_str_); +int *trace_seq_printf*(struct trace_seq pass:[*]_s_, const char pass:[*]_fmt_, _..._); +int *trace_seq_vprintf*(struct trace_seq pass:[*]_s_, const char pass:[*]_fmt_, va_list _args_); +int *trace_seq_do_printf*(struct trace_seq pass:[*]_s_); +int *trace_seq_do_fprintf*(struct trace_seq pass:[*]_s_, FILE pass:[*]_fp_); +-- + +DESCRIPTION +----------- +Trace sequences are used to allow a function to call several other functions +to create a string of data to use. + +The _trace_seq_init()_ function initializes the trace sequence _s_. + +The _trace_seq_destroy()_ function destroys the trace sequence _s_ and frees +all its resources that it had used. + +The _trace_seq_reset()_ function re-initializes the trace sequence _s_. All +characters already written in _s_ will be deleted. + +The _trace_seq_terminate()_ function terminates the trace sequence _s_. It puts +the null character pass:['\0'] at the end of the buffer. + +The _trace_seq_putc()_ function puts a single character _c_ in the trace +sequence _s_. + +The _trace_seq_puts()_ function puts a NULL terminated string _str_ in the +trace sequence _s_. + +The _trace_seq_printf()_ function puts a formated string _fmt _with +variable arguments _..._ in the trace sequence _s_. + +The _trace_seq_vprintf()_ function puts a formated string _fmt _with +list of arguments _args_ in the trace sequence _s_. + +The _trace_seq_do_printf()_ function prints the buffer of trace sequence _s_ to +the standard output stdout. + +The _trace_seq_do_fprintf()_ function prints the buffer of trace sequence _s_ +to the given file _fp_. + +RETURN VALUE +------------ +Both _trace_seq_putc()_ and _trace_seq_puts()_ functions return the number of +characters put in the trace sequence, or 0 in case of an error + +Both _trace_seq_printf()_ and _trace_seq_vprintf()_ functions return 0 if the +trace oversizes the buffer's free space, the number of characters printed, or +a negative value in case of an error. + +Both _trace_seq_do_printf()_ and _trace_seq_do_fprintf()_ functions return the +number of printed characters, or -1 in case of an error. + +EXAMPLE +------- +[source,c] +-- +#include +#include +... +struct trace_seq seq; +trace_seq_init(&seq); +... +void foo_seq_print(struct trace_seq *tseq, char *format, ...) +{ + va_list ap; + va_start(ap, format); + if (trace_seq_vprintf(tseq, format, ap) <= 0) { + /* Failed to print in the trace sequence */ + } + va_end(ap); +} + +trace_seq_reset(&seq); + +char *str = " MAN page example"; +if (trace_seq_puts(&seq, str) != strlen(str)) { + /* Failed to put str in the trace sequence */ +} +if (trace_seq_putc(&seq, ':') != 1) { + /* Failed to put ':' in the trace sequence */ +} +if (trace_seq_printf(&seq, " trace sequence: %d", 1) <= 0) { + /* Failed to print in the trace sequence */ +} +foo_seq_print( &seq, " %d\n", 2); + +trace_seq_terminate(&seq); +... + +if (trace_seq_do_printf(&seq) < 0 ) { + /* Failed to print the sequence buffer to the standard output */ +} +FILE *fp = fopen("trace.txt", "w"); +if (trace_seq_do_fprintf(&seq, fp) < 0 ) [ + /* Failed to print the sequence buffer to the trace.txt file */ +} + +trace_seq_destroy(&seq); +... +-- + +FILES +----- +[verse] +-- +*event-parse.h* + Header file to include in order to have access to the library APIs. +*trace-seq.h* + Header file to include in order to have access to trace sequences related APIs. +*-ltraceevent* + Linker switch to add when building a program that uses the library. +-- + +SEE ALSO +-------- +_libtraceevent(3)_, _trace-cmd(1)_ + +AUTHOR +------ +[verse] +-- +*Steven Rostedt* , author of *libtraceevent*. +*Tzvetomir Stoyanov* , author of this man page. +-- +REPORTING BUGS +-------------- +Report bugs to + +LICENSE +------- +libtraceevent is Free Software licensed under the GNU LGPL 2.1 + +RESOURCES +--------- +https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git