Re: [Tarantool-patches] [PATCH v3] build: enable cmake in curl build

[Igor Munkin <imun@tarantool.org>]

Sasha,

Thanks for the patch!

On 08.10.20, Alexander V. Tikhonov wrote:
> Initially tryed to change autoconf tools in Curl build to cmake and

Typo (again): s/tryed/tried/.

> found the following build issue on:
>   CentOS 6,7

Minor: IMHO, it's better to split these lines as you did in the commit
you're referring below.

>   Debian 8
>   Ubuntu 14.04
> 
>   Issue found:
>     CMake Error at CMakeLists.txt:41 (cmake_minimum_required):
>       CMake 3.0 or higher is required.  You are running version 2.8.12.2
> 
> To fix the issue removed the check of the version from curl sources

Typo: s/removed the check/check is removed/.

> in Tarantool's third party '<root Tarantool sources>/third_party/curl':
> 
>   12af024bc85606b14ffc415413a7e86e6bbee7eb "Enable curl build with old cmake"

Minor: We mention commits in the form
0000000000000000000000000000000000000000 ('commit message header'):
full 40-digits hash and the commit message header in parenthesis.

> 
> After this fix completely changed autoconf to cmake in curl build.
> Autoconf part completely removed and code cleaned up for cmake.

Typo: s/removed/is removed/.

> For curl cmake build all autoconf options were ported to cmake
> configuration call, check the accurate list of the change in [1].
> 
> Also the following issues resolved:
> 

<snipped>

> 3. Found issues with building Tarantool statically on Debian 9 and
>    its package build on CentOS 8.
> 
>    Building statically got the issues with openssl linking, like [2]:
> 
>      static-build/openssl-prefix/lib/libcrypto.a(threads_pthread.o): In function `CRYPTO_THREAD_lock_new':
>      threads_pthread.c:(.text+0x45): undefined reference to `pthread_rwlock_init'
> 
>    It happened because in openssl radically changed how threads-related
>    things were handled before 1.1.0 version. It required the application
>    to provide us with the locking functionality in form of callbacks.
>    Since 1.1.0, these matters are entirely internal, so libcrypto
>    requires the presence of the platform specific thread implementation
>    of our choosing, which is pthread on everything.
> 
>    After '-pthread' added to C compile flags package build on CentOS 8
>    failed with the issue [3]:
> 
>      /build/usr/src/debug/tarantool-2.6.0.141/third_party/curl/lib/warnless.c:101:4: error: #error "SIZEOF_CURL_OFF_T not defined"
>       #  error "SIZEOF_CURL_OFF_T not defined"
>          ^~~~~
>      /build/usr/src/debug/tarantool-2.6.0.141/third_party/curl/lib/warnless.c: In function 'curlx_uztoso':
>      /build/usr/src/debug/tarantool-2.6.0.141/third_party/curl/lib/warnless.c:192:40: error: 'CURL_MASK_SCOFFT' undeclared (first use in this function); did you mean 'CURL_MASK_SINT'?
>       return (curl_off_t)(uznum & (size_t) CURL_MASK_SCOFFT);
>                                            ^~~~~~~~~~~~~~~~
>                                            CURL_MASK_SINT
> 
>    To avoid of the issue decided to use '-pthread' flag only for openssl
>    when it had not this flag in openssl compilation:
> 
>      # check '-pthread' in openssl compile options
>      execute_process(COMMAND openssl version -f
>                      OUTPUT_VARIABLE OPENSSL_COMPILE_OPTIONS)
>      # add pthread library for openssl static library linking
>      if(NOT OPENSSL_COMPILE_OPTIONS MATCHES ".* -pthread .*")
>          list(APPEND LIBCURL_CMAKE_FLAGS "-DCMAKE_C_FLAGS=-pthread")
>      endif()

Minor: I doubt code duplication in sources and commit message makes the
changes clearer :) The description above is enough (except it lacks the
reason why CURL_MASK_SCOFFT is undeclared, but it looks like minor
details that can be changed in future or googled by inquisitive readers)

> 

<snipped>

> 
> Closes #4968
> Closes #5396
> Closes #5019

Minor (again): Please sort the issues above.

> 
> [1] - https://github.com/tarantool/tarantool/issues/4968#issue-617183031
> [2] - https://gitlab.com/tarantool/tarantool/-/jobs/779176133#L6021
> [3] - https://gitlab.com/tarantool/tarantool/-/jobs/778309145#L3060
> ---
> 
> 
> Github: https://github.com/tarantool/tarantool/tree/avtikhon/gh-4874-out-of-source-build-full-ci
> Issue: https://github.com/tarantool/tarantool/issues/4968
> Issue: https://github.com/tarantool/tarantool/issues/5396
> Issue: https://github.com/tarantool/tarantool/issues/5019
> 
> V3: Added explicitly all disabled flags.
>     Fixed #5396.
>     Removed fix for #5020 as not needed now.
> 
>  cmake/BuildLibCURL.cmake | 249 +++++++++++++++++++--------------------
>  1 file changed, 118 insertions(+), 131 deletions(-)
> 
> diff --git a/cmake/BuildLibCURL.cmake b/cmake/BuildLibCURL.cmake
> index 86fec39e9..911e49f11 100644
> --- a/cmake/BuildLibCURL.cmake
> +++ b/cmake/BuildLibCURL.cmake
> @@ -3,11 +3,12 @@ macro(curl_build)
>      set(LIBCURL_SOURCE_DIR ${PROJECT_SOURCE_DIR}/third_party/curl)
>      set(LIBCURL_BINARY_DIR ${PROJECT_BINARY_DIR}/build/curl/work)
>      set(LIBCURL_INSTALL_DIR ${PROJECT_BINARY_DIR}/build/curl/dest)
> +    set(LIBCURL_CMAKE_FLAGS "")
>  
>      message(STATUS "Looking for zlib")
>      find_path(ZLIB_INCLUDE_DIR zlib.h)
>      message(STATUS "Looking for zlib.h - ${ZLIB_INCLUDE_DIR}")
> -    if (BUILD_STATIC)
> +    if(BUILD_STATIC)

Minor: This line changes nothing except the whitespace (it looks like
rebase conflict resolution). Such changes only enlarge the patch, so I
believe they can be dropped. However, I have no strict objections,
regarding this one, since it doesn't introduce new hunks (ergo the
changes are quite local).

>          set(LIBZ_LIB_NAME libz.a)
>      else()
>          set(LIBZ_LIB_NAME z)
> @@ -15,44 +16,125 @@ macro(curl_build)
>      find_library(LIBZ_LIBRARY NAMES ${LIBZ_LIB_NAME})
>      message(STATUS "Looking for libz - ${LIBZ_LIBRARY}")
>  
> -    if (NOT ZLIB_INCLUDE_DIR OR NOT LIBZ_LIBRARY)
> +    if(NOT ZLIB_INCLUDE_DIR OR NOT LIBZ_LIBRARY)

Ditto.

>          message(FATAL_ERROR "Unable to find zlib")
>      endif()

<snipped>

> +
> +    # switch off the group of protocols with special flag HTTP_ONLY:
> +    #   ftp, file, ldap, ldaps, rtsp, dict, telnet, tftp, pop3, imap, smtp

I guess this comment is irrelevant considering the options you disabled
manually below.

> +    list(APPEND LIBCURL_CMAKE_FLAGS "-DHTTP_ONLY=ON")

<snipped>

> +    # In hardened mode, which enables -fPIE by default,
> +    # the cmake checks don't work without -fPIC.
> +    list(APPEND LIBCURL_CMAKE_FLAGS "-DCMAKE_REQUIRED_FLAGS=-fPIC")

As a result of the offline discussion this line is removed

> +

<snipped>

>  
>      include(ExternalProject)
>      ExternalProject_Add(
> @@ -62,101 +144,11 @@ macro(curl_build)

<snipped>

> -                --disable-symbol-hiding

There is <CURL_HIDDEN_SYMBOLS> option, that is ON (AFAIU, this
extension[1]). So, this change is inconsistent: you drop this configure
options and don't set the proper CMake flag.

<snipped>

> +        BUILD_COMMAND cd <BINARY_DIR> && $(MAKE) -j

The comment regarding this line is left unaddressed.

>          INSTALL_COMMAND cd <BINARY_DIR> && $(MAKE) install)

<snipped>

> -- 
> 2.25.1
> 

[1]: https://github.com/tarantool/curl/blob/5a1fc8d33808d7b22f57bdf9403cda7ff07b0670/CMake/CurlSymbolHiding.cmake#L24

-- 
Best regards,
IM