tinycbor: Pulling in patch from mynewt upstream PR

- Pulling in code from intel/tinycbor#83 as a
  patch to zephyr's ext/tinycbor. This is to facilitate the use of
  chained buffers functionality for tinycbor while it is in development
  on https://github.com/intel/tinycbor
- Bring tinycbor up to date with mynewt tinycbor
- Changing implementation of cbor_encoder_get_extra_bytes_needed() and
  cbor_encoder_get_buffer_size() as part of cbor_buf_writer APIs
- Move bytes_needed field from CborEncoder to the buf writer, this is
  needed by the tests mainly.
- Fix cbor_buf_cmp to do memcmp and return complemented result
  iterate_string_chunks(): fixing NULL compare at the end of string
  and moving it out of the iterate_string_chunks(). This is to avoid
  buffer specific parser calls in the function
- cbor_value_get_next_byte() is removed in mynewt version of tinycbor,
  so, we track offsets of the buffer which can be used for comparison
  in the parser tests instead of calculating the offset
- Making the decoder and parser APIs backwards compatible
- Adding encoder writer and parser reader as part of the encoder and
  parser structure. This is to make the encoder and parser use new
  function of encoder_writer and decoder_reader without breaking
  backwards compatibility.
- Making the old API use flat buffers by default
- Adding APIs for initializing encoder and parser with custom writer
  and reader
- Make the default writer and reader conditional based on
  NO_DFLT_READER/WRITER define. This is because we want a default
  reader/writer to avoid API changes.
- Use it->offset instead of it->ptr to track buffer offsets
- Update resolve_indicator() static api parameters to use cbor value
  and access offsets instead of taking pointers as input parameters
- In validate_container() do a byte by byte comparison instead of
  memcmp since we no longer have access to the buffer directly
- Also, use offsets instead of pointers to validate sorted maps
- Added a new define for conditionally compiling in float support
  (NO_FLOAT_SUPPORT).
- This is because we want the float support to be compiled in by
  default.
- Use static_assert macro instead of Static_assert. Changed to avoid
  build failures.
- Add api to get string chunk, this is a callback which can be used by
  buffer implementations to grab a string that is divided in chunks
  which spans across multiple chained buffers
- Add KConfig and CMakeList files for configuration and build
- Delete .gitignore and .gitattributes
- Remove tools, tests and examples as they are not really needed for
  building the library

Signed-off-by: Vipul Rahane <[email protected]>

Author: vrahane

ext/Kconfig

@@ -12,6 +12,8 @@ source "ext/hal/Kconfig"
 
 source "ext/lib/crypto/Kconfig"
 
+source "ext/lib/encoding/Kconfig"
+
 source "ext/debug/Kconfig"
 
 endmenu

ext/lib/CMakeLists.txt

@@ -1 +1,2 @@
 add_subdirectory(crypto)
+add_subdirectory(encoding)

ext/lib/encoding/CMakeLists.txt

@@ -0,0 +1 @@
+add_subdirectory_if_kconfig(tinycbor)

ext/lib/encoding/Kconfig

@@ -0,0 +1,24 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+menu "Encoding"
+
+source "ext/lib/encoding/tinycbor/Kconfig"
+
+endmenu

ext/lib/encoding/tinycbor/.appveyor.yml

@@ -0,0 +1,14 @@
+zephyr_interface_library_named(TINYCBOR)
+
+target_include_directories(TINYCBOR INTERFACE src)
+
+zephyr_library()
+zephyr_library_sources(
+    src/cbor_buf_reader.c
+    src/cbor_buf_writer.c
+    src/cborencoder.c
+    src/cborerrorstrings.c
+    src/cborparser.c
+)
+zephyr_library_link_libraries(TINYCBOR)
+target_link_libraries(TINYCBOR INTERFACE zephyr_interface)