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authorSteven Rostedt <srostedt@redhat.com>2012-04-06 00:47:53 +0200
committerFrederic Weisbecker <fweisbec@gmail.com>2012-04-25 12:28:28 +0200
commitf7d82350e597d76dc8765a55c7849843395728b0 (patch)
tree6e254dde9c6b30dc9f5dc4fb28d3eeec86382e32 /tools/lib/traceevent/trace-seq.c
parent4ace73eef52c651b8f58415fb4476f4791c95e72 (diff)
downloadvexpress-lsk-f7d82350e597d76dc8765a55c7849843395728b0.tar.gz
tools/events: Add files to create libtraceevent.a
Copy over the files from trace-cmd to the Linux tools directory such that applications like perf and latencytrace can use the more advanced parsing code. Because some of the file names of perf conflict with trace-cmd file names, the trace-cmd files have been renamed as follows: parse-events.c ==> event-parse.c parse-events.h ==> event-parse.h utils.h ==> event-utils.h The files have been updated to handle the changes to the header files but other than that, they are identical to what was in the trace-cmd repository. The history of these files, including authorship is available at the git repo: git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git The Makefile was also copied over, but most of it was removed to focus on the parse-events code first. The parts of the Makefile for the plugins have also been removed, but will be added back when the plugin code is copied over as well. But that may be in its own separate directory. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Arun Sharma <asharma@fb.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Diffstat (limited to 'tools/lib/traceevent/trace-seq.c')
-rw-r--r--tools/lib/traceevent/trace-seq.c199
1 files changed, 199 insertions, 0 deletions
diff --git a/tools/lib/traceevent/trace-seq.c b/tools/lib/traceevent/trace-seq.c
new file mode 100644
index 00000000000..d2f265b48cd
--- /dev/null
+++ b/tools/lib/traceevent/trace-seq.c
@@ -0,0 +1,199 @@
+/*
+ * Copyright (C) 2009 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ * This program 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 of the License (not later!)
+ *
+ * This program 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 program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+
+#include "event-parse.h"
+
+/*
+ * The TRACE_SEQ_POISON is to catch the use of using
+ * a trace_seq structure after it was destroyed.
+ */
+#define TRACE_SEQ_POISON ((void *)0xdeadbeef)
+#define TRACE_SEQ_CHECK(s) \
+do { \
+ if ((s)->buffer == TRACE_SEQ_POISON) \
+ die("Usage of trace_seq after it was destroyed"); \
+} while (0)
+
+/**
+ * trace_seq_init - initialize the trace_seq structure
+ * @s: a pointer to the trace_seq structure to initialize
+ */
+void trace_seq_init(struct trace_seq *s)
+{
+ s->len = 0;
+ s->readpos = 0;
+ s->buffer_size = TRACE_SEQ_BUF_SIZE;
+ s->buffer = malloc_or_die(s->buffer_size);
+}
+
+/**
+ * trace_seq_destroy - free up memory of a trace_seq
+ * @s: a pointer to the trace_seq to free the buffer
+ *
+ * Only frees the buffer, not the trace_seq struct itself.
+ */
+void trace_seq_destroy(struct trace_seq *s)
+{
+ if (!s)
+ return;
+ TRACE_SEQ_CHECK(s);
+ free(s->buffer);
+ s->buffer = TRACE_SEQ_POISON;
+}
+
+static void expand_buffer(struct trace_seq *s)
+{
+ s->buffer_size += TRACE_SEQ_BUF_SIZE;
+ s->buffer = realloc(s->buffer, s->buffer_size);
+ if (!s->buffer)
+ die("Can't allocate trace_seq buffer memory");
+}
+
+/**
+ * trace_seq_printf - sequence printing of trace information
+ * @s: trace sequence descriptor
+ * @fmt: printf format string
+ *
+ * It returns 0 if the trace oversizes the buffer's free
+ * space, 1 otherwise.
+ *
+ * The tracer may use either sequence operations or its own
+ * copy to user routines. To simplify formating of a trace
+ * trace_seq_printf is used to store strings into a special
+ * buffer (@s). Then the output may be either used by
+ * the sequencer or pulled into another buffer.
+ */
+int
+trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
+{
+ va_list ap;
+ int len;
+ int ret;
+
+ TRACE_SEQ_CHECK(s);
+
+ try_again:
+ len = (s->buffer_size - 1) - s->len;
+
+ va_start(ap, fmt);
+ ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
+ va_end(ap);
+
+ if (ret >= len) {
+ expand_buffer(s);
+ goto try_again;
+ }
+
+ s->len += ret;
+
+ return 1;
+}
+
+/**
+ * trace_seq_vprintf - sequence printing of trace information
+ * @s: trace sequence descriptor
+ * @fmt: printf format string
+ *
+ * The tracer may use either sequence operations or its own
+ * copy to user routines. To simplify formating of a trace
+ * trace_seq_printf is used to store strings into a special
+ * buffer (@s). Then the output may be either used by
+ * the sequencer or pulled into another buffer.
+ */
+int
+trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
+{
+ int len;
+ int ret;
+
+ TRACE_SEQ_CHECK(s);
+
+ try_again:
+ len = (s->buffer_size - 1) - s->len;
+
+ ret = vsnprintf(s->buffer + s->len, len, fmt, args);
+
+ if (ret >= len) {
+ expand_buffer(s);
+ goto try_again;
+ }
+
+ s->len += ret;
+
+ return len;
+}
+
+/**
+ * trace_seq_puts - trace sequence printing of simple string
+ * @s: trace sequence descriptor
+ * @str: simple string to record
+ *
+ * The tracer may use either the sequence operations or its own
+ * copy to user routines. This function records a simple string
+ * into a special buffer (@s) for later retrieval by a sequencer
+ * or other mechanism.
+ */
+int trace_seq_puts(struct trace_seq *s, const char *str)
+{
+ int len;
+
+ TRACE_SEQ_CHECK(s);
+
+ len = strlen(str);
+
+ while (len > ((s->buffer_size - 1) - s->len))
+ expand_buffer(s);
+
+ memcpy(s->buffer + s->len, str, len);
+ s->len += len;
+
+ return len;
+}
+
+int trace_seq_putc(struct trace_seq *s, unsigned char c)
+{
+ TRACE_SEQ_CHECK(s);
+
+ while (s->len >= (s->buffer_size - 1))
+ expand_buffer(s);
+
+ s->buffer[s->len++] = c;
+
+ return 1;
+}
+
+void trace_seq_terminate(struct trace_seq *s)
+{
+ TRACE_SEQ_CHECK(s);
+
+ /* There's always one character left on the buffer */
+ s->buffer[s->len] = 0;
+}
+
+int trace_seq_do_printf(struct trace_seq *s)
+{
+ TRACE_SEQ_CHECK(s);
+ return printf("%.*s", s->len, s->buffer);
+}