Add missing type assignment operator

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

diff --git a/common-trace-format-proposal.txt b/common-trace-format-proposal.txt
index 361c2ec39c21f35ceb06363b218b0c683113d284..4cd7e7c751fcdbb851ac1f0c500471826827a269 100644 (file)
--- a/common-trace-format-proposal.txt
+++ b/common-trace-format-proposal.txt
@@ -68,14 +68,10 @@ A metadata event stream contains information on trace event types. It describes:
 3. Event stream
 
 An event stream is divided in contiguous event packets of variable size. These
-subdivisions have a variable size. An event packet can contain a certain amount
-of padding at the end. The rationale for the event stream design choices is
-explained in Appendix B. Stream Header Rationale.
-
-An event stream is divided in contiguous event packets of variable size. These
-subdivisions have a variable size. An event packet can contain a certain amount
-of padding at the end.  The stream header is repeated at the beginning of each
-event packet.
+subdivisions have a variable size. An event packet can contain a certain
+amount of padding at the end. The stream header is repeated at the
+beginning of each event packet. The rationale for the event stream
+design choices is explained in Appendix B. Stream Header Rationale.
 
 The event stream header will therefore be referred to as the "event packet
 header" throughout the rest of this document.
@@ -791,10 +787,12 @@ variant field), a declaration is followed by a declarator, which specify
 the newly defined type name (for typedef), or the field name (for
 declarations located within structure and variants). Array and sequence,
 declared with square brackets ("[" "]"), are part of the declarator,
-similarly to C99.
+similarly to C99. The enumeration type specifier and variant tag name
+(both specified with "<" ">") are part of the type specifier.
 
 A definition associates a type to a location in the event structure
-hierarchy (see Section 6).
+hierarchy (see Section 6). This association is denoted by ":=", as shown
+in Section 7.3.
 
 
 7.2 Metadata Scopes
@@ -845,8 +843,14 @@ different scopes. There is no possible conflict, because the dynamic
 scope must be specified when a variant refers to a tag field located in
 a different dynamic scope.
 
+The information available in the dynamic scopes can be thought of as the
+current tracing context. At trace production, information about the
+current context is saved into the specified scope field levels. At trace
+consumption, for each event, the current trace context is therefore
+readable by accessing the upper dynamic scopes.
 
-7.2 Metadata Examples
+
+7.3 Metadata Examples
 
 The grammar representing the CTF metadata is presented in
 Appendix C. CTF Metadata Grammar. This section presents a rather ligher
@@ -1240,6 +1244,9 @@ unary-operator: one of
 assignment-operator:
        =
 
+type-assignment-operator:
+       :=
+
 constant-expression:
        unary-expression
 
@@ -1280,6 +1287,7 @@ type-specifier:
        unsigned
        _Bool
        _Complex
+       _Imaginary
        struct-specifier
        variant-specifier
        enum-specifier