llvm2lcov: translate from 'llvm-cov' JSON to LCOV format.

Primary use is to support MC/DC - which is not currently supported by
'llvm-cov export -format=lcov' or 'llvm-cov gcov'.

Signed-off-by: Henry Cox <[email protected]>

Author: henry2cox

Makefile

@@ -66,7 +66,10 @@ FILES   := README Makefile lcovrc \
 DIST_CONTENT := CONTRIBUTING COPYING README Makefile lcovrc \
 	bin example lib man rpm scripts tests
 
-EXES = lcov genhtml geninfo genpng gendesc perl2lcov py2lcov xml2lcov xml2lcovutil.py
+EXES = \
+	lcov genhtml geninfo genpng gendesc \
+	perl2lcov py2lcov xml2lcov xml2lcovutil.py \
+	llvm2lcov
 # there may be both public and non-public user scripts - so lets not show
 #   any of their names
 SCRIPTS = $(shell ls scripts | grep -v -E '([\#\~]|\.orig|\.bak|\.BAK)' )

README

@@ -1,6 +1,6 @@
 -------------------------------------------------
 - README file for the LTP GCOV extension (LCOV) -
-- Last changes: 2024-11-12
+- Last changes: 2024-11-20
 -------------------------------------------------
 
 Description
@@ -59,6 +59,7 @@ Further README contents
   bin/genhtml        - Tool for creating HTML output from LCOV data
   bin/gendesc        - Tool for creating description files as used by genhtml
   bin/perl2lcov      - Tool to translate Perl Devel::Cover data to lcov format
+  bin/llvm2lcov      - Tool to translate LLVM 'llvm-cov' JSON data to LCOV format
   bin/py2lcov        - Tool to translate Python Coverage.py to lcov format
   bin/xml2lcov       - Tool to translate Cobertura-like XML coverage data
                        to lcov format
@@ -437,9 +438,18 @@ New features and capabilities fall into 7 major categories:
 
      Related options: --parallel, --memory, --profile
 
-  g) Language support
+  g) Language/tool support
 
-     Added 'py2lcov', 'perl2lcov' and 'xml2lcov' scripts.
+     Added 'llvm2lcov', 'py2lcov', 'perl2lcov' and 'xml2lcov' scripts.
+
+       - llvm2lcov:
+
+           translates JSON coverage data generated by 'llvm-cov export -format=text ...'
+           to lcov format.
+
+           See "llvm2lcov --help" for brief instruction on how to use the
+           translator.  Note tha llvm2lcov uses a similar set of command line
+           and configuration file options as lcov, genhtml, and geninfo.
 
        - py2lcov:
 

bin/geninfo

@@ -2392,17 +2392,8 @@ sub read_intermediate_text($$)
 sub read_intermediate_json($$$)
 {
     my ($gcov_filename, $data, $basedir_ref) = @_;
-    my $text;
-
-    {
-        # intermediate JSON contains the demangled name
-        my $f     = InOutFile->in($gcov_filename);
-        my $h     = $f->hdl();
-        my @lines = <$h>;
-        $text = join("\n", @lines);
-    }
-
-    my $json = JsonSupport::decode($text);    # imported from lcovutil.pm
+    # intermediate JSON contains the demangled name
+    my $json = JsonSupport::load($gcov_filename);    # imported from lcovutil.pm
     if (!defined($json) ||
         !exists($json->{"files"}) ||
         ref($json->{"files"} ne "ARRAY")) {