Hans Johnson
97d1de3d22
Automatically extract version information from the zstd.h file. Use naming of variables consisent with modern cmake and https://semver.org/ (Semantic Versioning 2.0.0, MAJOR, MINOR, PATCH) Modern versions of cmake provide consistent paradigms for configuring project external interface values. This set of changes provide a back port of some of cmake 3+ paradigms back to cmake 2.8.9. Set and allow use of the current cmake policies for newer versions of cmake when available to allow for modern compiler features to be utilized when available. NOTE: The intent is that future modifications to cmake will enable (conditional on cmake version support) the ability to support modern linkage, and target export mechanisms. Those future changes will make incorporating zstd into other packages much easier. This patch also allows the more rigourous error checking of commmon cmake errors to be preformed by cmake (i.e. more stringent syntax checking and create errors for common hard to find misuses of cmake variables). This patch also provides support for modern compiler support options by cmake (like enabling interprocedural optimization if link time optimizations are known to be supported by the compiler envirionment. IPO can be supported by setting the CMAKE_INTERPROCEDURAL_OPTIMIZATION variable for newer versions of cmake.
Cmake contributions
Contributions to the cmake build configurations are welcome. Please use case sensitivity that matches modern (ie. cmake version 2.6 and above) conventions of using lower-case for commands, and upper-case for varibles.
CMake Style Recommendations
Indent all code correctly, i.e. the body of
- if/else/endif
- foreach/endforeach
- while/endwhile
- macro/endmacro
- function/endfunction
Use spaces for indenting, 2, 3 or 4 spaces preferably. Use the same amount of spaces for indenting as is used in the rest of the file. Do not use tabs.
Upper/lower casing
Most important: use consistent upper- or lowercasing within one file !
In general, the all-lowercase style is preferred.
So, this is recommended:
add_executable(foo foo.c)
These forms are discouraged
ADD_EXECUTABLE(bar bar.c)
Add_Executable(hello hello.c)
aDd_ExEcUtAbLe(blub blub.c)
End commands
To make the code easier to read, use empty commands for endforeach(), endif(), endfunction(), endmacro() and endwhile(). Also, use empty else() commands.
For example, do this:
if(FOOVAR)
some_command(...)
else()
another_command(...)
endif()
and not this:
if(BARVAR)
some_other_command(...)
endif(BARVAR)
Other resources for best practices
https://cmake.org/cmake/help/latest/manual/cmake-developer.7.html#modules