The steps to add this functionality are from the cmake tutorial:
https://cmake.org/cmake/help/latest/guide/tutorial/index.html
The include directories being set on the targets is necessary
for dependent targets. There is some redundancy with the
INCLUDE_DIRECTORIES calls alreday present, but I left it alone
to make the PR smaller and more approachable.
The project currently uses mixed cases in functions. This uses
lowercase on calls I touched, as this is what CMake documentation
uses and seems to be the preferred way.
I also started wrapping long lines, as some of the lines I touched
were over 170 characters.
I tested this on both Mac OS 10.15 Catalina and CentOS 7 (with
devtoolset-7) with CMake 3.10.3.
Will work on tests in CI next.
A user of the protobuf-c library is confronted with MSVC warnings about missing
PDB if the library happens to be built/configured using the CMAKE_BUILD_TYPE
"Debug" or "RelWithDebInfo". This commit deals away with the warning by
installing the "protobuf-c.pdb" alongside the lib. The .pdb is installed only
if it exists. Configuring "Release" or building under Linux won't produce and
won't install the PDB.
For certain platforms where autotools is not the preferred build system,
provide a fallback cmake file that can compile protoc-c and a static
library of libprotobuf-c.
Based on the file from alex85k's protobuf-c repository.
(Issue #168.)
