Change metadata header to include version

[ctf.git] / common-trace-format-specification.txt

diff --git a/common-trace-format-specification.txt b/common-trace-format-specification.txt
index 8d5cc928b264fc1a11bdb72655a394236d8d1d52..704968d1054268990b4ed83d3095581d8f6156a1 100644 (file)
--- a/common-trace-format-specification.txt
+++ b/common-trace-format-specification.txt
@@ -933,7 +933,21 @@ CTF stream packet facilities (checksumming, compression, encryption,
 network-readiness) for meta-data stream generated and transported by a
 tracer.
 
 network-readiness) for meta-data stream generated and transported by a
 tracer.
 

-The text-only meta-data file is a plain text TSDL description.
+The text-only meta-data file is a plain-text TSDL description. This file
+must begin with the following characters to identify the file as a CTF
+TSDL text-based metadata file (without the double-quotes) :
+
+"/* CTF"
+
+It must be followed by a space, and the version of the specification
+followed by the CTF trace, e.g.:
+
+" 1.8"
+
+These characters allow automated discovery of file type and CTF
+specification version. They are interpreted as a the beginning of a
+comment by the TSDL metadata parser.  The comment can be continued to
+contain extra commented characters before it is closed.

 
 The packet-based meta-data is made of "meta-data packets", which each
 start with a meta-data packet header. The packet-based meta-data
 
 The packet-based meta-data is made of "meta-data packets", which each
 start with a meta-data packet header. The packet-based meta-data


@@ -958,6 +972,8 @@ struct metadata_packet_header {
   uint8_t  compression_scheme;         /* 0 if unused */
   uint8_t  encryption_scheme;          /* 0 if unused */
   uint8_t  checksum_scheme;            /* 0 if unused */
   uint8_t  compression_scheme;         /* 0 if unused */
   uint8_t  encryption_scheme;          /* 0 if unused */
   uint8_t  checksum_scheme;            /* 0 if unused */

+  uint8_t  major;                      /* CTF spec version major number */
+  uint8_t  minor;                      /* CTF spec version minor number */

 };
 
 The packet-based meta-data can be converted to a text-only meta-data by
 };
 
 The packet-based meta-data can be converted to a text-only meta-data by