[PATCH v4 19/25] trace-cmd library: Handle the extended DONE option

["Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com>]

In trace file version 7 the DONE option is extended to store the offset
in the file to the next options section. This way a list of options
sections can be stored in the file. Added logic to recursively read all
option sections from the file.

Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
---
 lib/trace-cmd/include/trace-cmd-local.h |  1 +
 lib/trace-cmd/trace-input.c             | 42 +++++++++++++++++++++++--
 lib/trace-cmd/trace-output.c            |  2 +-
 3 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/lib/trace-cmd/include/trace-cmd-local.h b/lib/trace-cmd/include/trace-cmd-local.h
index d3760483..4b26960f 100644
--- a/lib/trace-cmd/include/trace-cmd-local.h
+++ b/lib/trace-cmd/include/trace-cmd-local.h
@@ -51,5 +51,6 @@ struct cpu_data_source {
 int out_write_cpu_data(struct tracecmd_output *handle, int cpus,
 		       struct cpu_data_source *data, const char *buff_name);
 off64_t msg_lseek(struct tracecmd_msg_handle *msg_handle, off_t offset, int whence);
+unsigned long long get_last_option_offset(struct tracecmd_input *handle);
 
 #endif /* _TRACE_CMD_LOCAL_H */
diff --git a/lib/trace-cmd/trace-input.c b/lib/trace-cmd/trace-input.c
index 70be9988..6137fc89 100644
--- a/lib/trace-cmd/trace-input.c
+++ b/lib/trace-cmd/trace-input.c
@@ -175,6 +175,7 @@ struct tracecmd_input {
 	struct file_section	*sections;
 	bool			options_init;
 	unsigned long long	options_start;
+	unsigned long long	options_last_offset;
 	size_t			total_file_size;
 
 	/* For custom profilers. */
@@ -2863,6 +2864,30 @@ tracecmd_search_task_map(struct tracecmd_input *handle,
 	return lib;
 }
 
+__hidden unsigned long long get_last_option_offset(struct tracecmd_input *handle)
+{
+	return handle->options_last_offset;
+}
+
+static int handle_option_done(struct tracecmd_input *handle, char *buf, int size)
+{
+	unsigned long long offset;
+
+	if (size < 8)
+		return -1;
+	offset = lseek64(handle->fd, 0, SEEK_CUR);
+	if (offset >= size)
+		handle->options_last_offset = offset - size;
+	offset = tep_read_number(handle->pevent, buf, 8);
+	if (!offset)
+		return 0;
+
+	if (lseek64(handle->fd, offset, SEEK_SET) == (off_t)-1)
+		return -1;
+
+	return handle_options(handle);
+}
+
 static inline int save_read_number(struct tep_handle *tep, char *data, int *data_size,
 				   int *read_pos, int bytes, unsigned long long *num)
 {
@@ -2965,19 +2990,27 @@ static int handle_options(struct tracecmd_input *handle)
 	long long offset;
 	unsigned short option;
 	unsigned int size;
+	unsigned short id, flags;
 	char *cpustats = NULL;
 	struct hook_list *hook;
 	char *buf;
 	int cpus;
 	int ret;
 
-	handle->options_start = lseek64(handle->fd, 0, SEEK_CUR);
+	if (!HAS_SECTIONS(handle)) {
+		handle->options_start = lseek64(handle->fd, 0, SEEK_CUR);
+	} else {
+		if (read_section_header(handle, &id, &flags, NULL, NULL))
+			return -1;
+		if (id != TRACECMD_OPTION_DONE)
+			return -1;
+	}
 
 	for (;;) {
 		if (read2(handle, &option))
 			return -1;
 
-		if (option == TRACECMD_OPTION_DONE)
+		if (!HAS_SECTIONS(handle) && option == TRACECMD_OPTION_DONE)
 			break;
 
 		/* next 4 bytes is the size of the option */
@@ -3113,7 +3146,10 @@ static int handle_options(struct tracecmd_input *handle)
 			section_add_or_update(handle, option, -1,
 					      tep_read_number(handle->pevent, buf, 8), 0);
 			break;
-
+		case TRACECMD_OPTION_DONE:
+			ret = handle_option_done(handle, buf, size);
+			free(buf);
+			return ret;
 		default:
 			tracecmd_warning("unknown option %d", option);
 			break;
diff --git a/lib/trace-cmd/trace-output.c b/lib/trace-cmd/trace-output.c
index ffcc62e1..b21aaf5d 100644
--- a/lib/trace-cmd/trace-output.c
+++ b/lib/trace-cmd/trace-output.c
@@ -2151,7 +2151,7 @@ struct tracecmd_output *tracecmd_get_output_handle_fd(int fd)
 	tep_ref(handle->pevent);
 	handle->page_size = tracecmd_page_size(ihandle);
 	handle->file_version = tracecmd_get_in_file_version(ihandle);
-	handle->options_start = tracecmd_get_options_offset(ihandle);
+	handle->options_start = get_last_option_offset(ihandle);
 	list_head_init(&handle->options);
 	list_head_init(&handle->buffers);
 
-- 
2.31.1