cmake: support sudo make uninstall

[jasjuang]

This features reduces the pain of having to remove the installed libraries and headers in /usr/local/ one by one.

Before this change, after sudo make install

Install the project...
-- Install configuration: ""
-- Up-to-date: /usr/local/bin/curl-config
-- Up-to-date: /usr/local/lib/pkgconfig/libcurl.pc
-- Up-to-date: /usr/local/include/curl/curlbuild.h
-- Up-to-date: /usr/local/include/curl
-- Up-to-date: /usr/local/include/curl/multi.h
-- Up-to-date: /usr/local/include/curl/easy.h
-- Up-to-date: /usr/local/include/curl/mprintf.h
-- Up-to-date: /usr/local/include/curl/curl.h
-- Up-to-date: /usr/local/include/curl/curlrules.h
-- Up-to-date: /usr/local/include/curl/typecheck-gcc.h
-- Up-to-date: /usr/local/include/curl/curlver.h
-- Up-to-date: /usr/local/include/curl/stdcheaders.h
-- Up-to-date: /usr/local/lib/libcurl.so
-- Up-to-date: /usr/local/bin/curl

there is no easy ways to remove these files, but with this change we can simply type sudo make uninstall and

Scanning dependencies of target uninstall
/usr/local
-- Uninstalling /usr/local/bin/curl-config
-- Uninstalling /usr/local/lib/pkgconfig/libcurl.pc
-- Uninstalling /usr/local/include/curl/curlbuild.h
-- Uninstalling /usr/local/include/curl/multi.h
-- Uninstalling /usr/local/include/curl/easy.h
-- Uninstalling /usr/local/include/curl/mprintf.h
-- Uninstalling /usr/local/include/curl/curl.h
-- Uninstalling /usr/local/include/curl/curlrules.h
-- Uninstalling /usr/local/include/curl/typecheck-gcc.h
-- Uninstalling /usr/local/include/curl/curlver.h
-- Uninstalling /usr/local/include/curl/stdcheaders.h
-- Uninstalling /usr/local/lib/libcurl.so
-- Uninstalling /usr/local/bin/curl
Built target uninstall

[mention-bot]

@jasjuang, thanks for your PR! By analyzing the history of the files in this pull request, we identified @billhoffman, @Sukender and @jzakrzewski to be potential reviewers.

[coveralls]

Coverage increased (+0.05%) to 76.062% when pulling badda39 on jasjuang:master into e909de6 on curl:master.

[snikulov]

@jasjuang Bad idea. If you required sudo to install why don't you call uninstall without sudo and push it into build system?

@bagder I suggest declining this PR.

[snikulov]

@jasjuang @bagder Sorry for my previous comment. Didn't get it for the first time. Will check it today evening.
Again, sorry for the noise.

[snikulov]

@bagder this PR just copy-paste from CMake FAQ https://cmake.org/Wiki/CMake_FAQ#Can_I_do_.22make_uninstall.22_with_CMake.3F

So depending on your decision.
If make uninstall is required, you can merge it.
Personally, I don't like this idea and suggesting @jasjuang focus on CPack support instead.

[jasjuang]

@snikulov Not sure why you don't like this idea. This is a common feature for most open source libraries that supports cmake like OpenCV, glm, glfw, glew, pcl, ceres, glog, gflags, tinyxml2 etc. Without this PR, how would you remove the files installed in /usr/local easily?

[snikulov]

@jasjuang As I already mentioned, I prefer to use CPack to make a package for installation.
I rarely keep build directory to run make uninstall from it.
To uninstall something from build directory I will use

xargs rm < install_manifest.txt

as mentioned on the link where you copy it.
It simply shorter.

[jasjuang]

@snikulov Well, sudo make uninstall is shorter than sudo xargs rm < install_manifest.txt. Also, this is beneficial for windows as well, I can run the uninstall target to remove the installed files without having to manually delete it.

[snikulov]

@jasjuang matter of taste. It's shorter because of increased code size under your control and support.

[bagder]

In general I think it makes sense to support "make uninstall" as an opposite to "make install", and the autotools build supports it already.

This code seems to look for and use a install_manifest.txt file to know what specific files to uninstall? What's that and how does it get created?

[jasjuang]

@bagder install_manifest.txt is created by cmake as long as the install functions are been written inside the CMakeLists. It records what files should be installed.

[snikulov]

@bagder then merge it. As I've already mentioned it's copy-paste from cmake F.A.Q., so I see no issue with it.

[bagder]

Thanks!