[Qemu-devel] [PATCH 05/10] trace: [tracetool] Common functions to manage event arguments

[Lluís Vilanova]

This adds:

* zip_lists: Pair elements from two lists.
* get_argtypes: Get the list of types of the arguments; can optionally transform
  the types in the process.

The function 'get_args' is modified to use a combination of 'get_argnames',
'get_argtypes', 'zip_lists' and, optionally, use the type transformation
capabilities of 'get_argtypes'.

Signed-off-by: Lluís Vilanova <address@hidden>
---
 scripts/tracetool |  117 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 116 insertions(+), 1 deletions(-)

diff --git a/scripts/tracetool b/scripts/tracetool
index 4c9951d..f2b6680 100755
--- a/scripts/tracetool
+++ b/scripts/tracetool
@@ -74,15 +74,130 @@ has_property()
     return 1
 }
 
+# Convenience function to pair elements from two comma-separated lists of equal
+# size.
+# 1: first list
+# 2: second list
+# 3: printf format for each pair of elements (optional, default: "%s %s, ")
+zip_lists()
+{
+    [ -n "$1" -a -n "$2" ] || return
+
+    local format
+    format=$3
+    [ -n "$format" ] || format="%s %s, "
+
+    local i elem accum
+    i=1
+    accum=""
+    for elem in $1; do
+        if [ "$elem" = "${elem%,}" ]; then
+            accum="$accum $elem"
+        else
+            accum="$accum ${elem%,}"
+            eval __elem_$i=\"$accum\"
+            i=$(($i + 1))
+            accum=""
+        fi
+    done
+    eval __elem_$i=\"$accum\"
+
+    local tmp res
+    accum=""
+    res=""
+    i=1
+    for elem in $2; do
+        if [ "$elem" = "${elem%,}" ]; then
+            accum="$accum $elem"
+        else
+            accum="$accum ${elem%,}"
+            eval tmp=\$__elem_$i
+            tmp=$(printf "$format" "$tmp" "$accum")
+            res="$res$tmp"
+            i=$(($i + 1))
+            accum=""
+        fi
+    done
+    eval tmp=\$__elem_$i
+    tmp=$(printf "$format" "$tmp" "$accum")
+    res="$res$tmp"
+    res="${res%, }"
+    echo $res
+}
+
 # Get the argument list of a trace event, including types and names
+# 1: event name
+# 2: passed as the second argument to 'get_argtypes' (optional)
 get_args()
 {
     local args
     args=${1#*\(}
     args=${args%%\)*}
-    echo "$args"
+
+    if [ -z "$2" -o "$args" = "void" ]; then
+        echo "$args"
+    else
+        local argtypes argnames res
+        argtypes=$(get_argtypes "$1" $2)
+        argnames=$(get_argnames "$1" ",")
+        res=$(zip_lists "$argtypes" "$argnames")
+        echo "${res#, }"
+    fi
 }
 
+# Get the argument type list of a trace event
+# 1: event name
+# 2: function to translate each of the types (optional, default: nil_type)
+get_argtypes()
+{
+    local translate field type res
+
+    translate=$2
+    [ -n "$translate" ] || translate=nil_type
+
+    res=""
+    type=""
+    for field in $(get_args "$1"); do
+        if [ "${field%,}" != "${field}" ]; then
+            # it's a name, but can have a star in it
+            [ "${field#\*}" = "$field" ] || type="${type}*"
+            # trim spaces
+            type="${type## }"
+            type="${type%% }"
+            # translate
+            type=$($translate "$type")
+            res="$res$type, "
+            type=""
+        else
+            # types can have spaces
+            type="$type $field"
+        fi
+    done
+
+    # remove the accumulated name
+    field="${type##* }"
+    type="${type% *}"
+
+    # trim spaces
+    type="${type## }"
+    type="${type%% }"
+
+    # it's a name, but can have a star in it
+    [ "${field#\*}" = "$field" ] || type="${type}*"
+    # translate
+    type=$($translate "$type")
+    res="$res$type"
+
+    echo $res
+}
+
+# No-op type translator for get_argtypes
+nil_type()
+{
+    echo "$1"
+}
+
+
 # Get the argument name list of a trace event
 get_argnames()
 {