lib/addoninfo.cpp: Add JSON schema validation.

For JSON schema validation in cpp code, valijson
(https://github.com/tristanpenman/valijson) is added. It supports picojson and
is actively maintained. It is used in one-header-include style, because it
seems the simplest solution, for now at least. The header is added, alongside
the LICENSE file, in externals/valijson/.

Various warnings that are emitted compiling the default code generated by
valijson are fixed; these fixes are pushed upstream.

As JSON is now validated against a schema, various ad-hoc checks could be
safely removed.

A simple way to test addon JSON schema validation, is to invoke cppcheck using:

   cppcheck --addon='{"script":1}' test.c

A minor bugfix is that the file specified by "executable" was searched using
getFullPath() with fileName as the second argument; it looks like this should
have been exename.

The fileName argument of parseAddonInfo() is only used for log messages, and is
now replaced by the string "inline JSON" instead of the actual JSON string that
was parsed. The command as given above will therefore output:

   Loading inline JSON failed. JSON schema validation failed: <root> [script]
   Value type not permitted by 'type' constraint., <root> Failed to validate
   against schema associated with property name 'script'.

The addon JSON unit tests are also updated and now operate on JSON specified on
the command line.

.github/workflows/CI-unixish.yml

@@ -242,7 +242,7 @@ jobs:
 
       - name: Check syntax with NONNEG
         run: |
-          ls lib/*.cpp | xargs -n 1 -P $(nproc) g++ -fsyntax-only -std=c++0x -Ilib -Iexternals -Iexternals/picojson -Iexternals/simplecpp -Iexternals/tinyxml2 -DNONNEG
+          ls lib/*.cpp | xargs -n 1 -P $(nproc) g++ -fsyntax-only -std=c++0x -Ilib -Iexternals -Iexternals/picojson -Iexternals/valijson -Iexternals/simplecpp -Iexternals/tinyxml2 -DNONNEG
 
   build_qmake:
 

Makefile

@@ -168,7 +168,7 @@ ifndef PREFIX
 endif
 
 ifndef INCLUDE_FOR_LIB
-    INCLUDE_FOR_LIB=-Ilib -isystem externals -isystem externals/picojson -isystem externals/simplecpp -isystem externals/tinyxml2
+    INCLUDE_FOR_LIB=-Ilib -isystem externals -isystem externals/picojson -isystem externals/valijson -isystem externals/simplecpp -isystem externals/tinyxml2
 endif
 
 ifndef INCLUDE_FOR_CLI

createrelease

@@ -11,7 +11,7 @@
 #
 # self check, fix critical issues:
 # make clean && make CXXFLAGS=-O2 MATCHCOMPILER=yes -j4
-# ./cppcheck -D__CPPCHECK__ -D__GNUC__ -DCHECK_INTERNAL -DHAVE_RULES --std=c++11 --library=cppcheck-lib --library=qt --enable=style --inconclusive --inline-suppr --suppress=bitwiseOnBoolean --suppress=shadowFunction --suppress=useStlAlgorithm --suppress=*:externals/picojson.h --suppress=functionConst --suppress=functionStatic --xml cli gui/*.cpp lib 2> selfcheck.xml
+# ./cppcheck -D__CPPCHECK__ -D__GNUC__ -DCHECK_INTERNAL -DHAVE_RULES --std=c++11 --library=cppcheck-lib --library=qt --enable=style --inconclusive --inline-suppr --suppress=bitwiseOnBoolean --suppress=shadowFunction --suppress=useStlAlgorithm --suppress=*:externals/picojson.h --suppress=*:externals/valijson/valijson_picojson_bundled.hpp --suppress=functionConst --suppress=functionStatic --xml cli gui/*.cpp lib 2> selfcheck.xml
 #
 # Generate lib/checkers.cpp (TODO the premium checkers should not be statically coded)
 # cd ~/cppchecksolutions/cppcheck && python3 tools/get_checkers.py > lib/checkers.cpp

externals/externals.pri

@@ -1,9 +1,11 @@
 INCLUDEPATH += $${PWD} \
                $${PWD}/picojson \
+               $${PWD}/valijson \
                $${PWD}/simplecpp \
                $${PWD}/tinyxml2
 
 HEADERS += $${PWD}/picojson/picojson.h \
+           $${PWD}/valijson/valijson_picojson_bundled.hpp \
            $${PWD}/simplecpp/simplecpp.h \
            $${PWD}/tinyxml2/tinyxml2.h
 

externals/valijson/LICENSE

@@ -0,0 +1,23 @@
+Copyright (c) 2016, Tristan Penman
+Copyright (c) 2016, Akamai Technologies, Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.