Can't add libp2p to project using hunter( libp2p versions available: [] [hunter ** INTERNAL **] Unexpected empty string)

[Kintawesar]

• In manjaro Linux kernel 4.19.187-1-MANJARO
• cmake 3.20.1
• gcc 10.2

download HunterGate.cmake,

in main CMakeLists.txt

include("cmake/HunterGate.cmake")

HunterGate(
    URL "https://github.com/cpp-pm/hunter/archive/v0.23.297.tar.gz"
    SHA1 "3319fe6a3b08090df7df98dee75134d68e2ef5a3"
)
    
project(sync_db_cpp LANGUAGES CXX)
hunter_add_package(libp2p)
find_package(libp2p REQUIRED)

then I try to make project using command

cmake -H. -B_builds -DHUNTER_STATUS_DEBUG=ON -DCMAKE_BUILD_TYPE=Release

-- [hunter *** DEBUG *** 2021-04-25T17:05:02] HUNTER_ROOT set using HOME environment variable
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] HUNTER_ROOT: /home/dev/.hunter
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] Settings (initialize):
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] HunterGate done (NO)
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] Cache init (YES)
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] Single-configuration generator
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] Using default cache server
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] List of cache servers:
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] * https://github.com/cpp-pm/hunter-cache
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] Settings (finalize):
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] HunterGate done (NO)
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] Cache init (YES)
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] Variables from HunterGate:
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] HUNTER_GATE_ROOT: /home/dev/.hunter
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] HUNTER_GATE_VERSION: 0.23.297
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] HUNTER_GATE_SHA1: 3319fe6a3b08090df7df98dee75134d68e2ef5a3
-- [hunter] Calculating Toolchain-SHA1
-- [hunter *** DEBUG *** 2021-04-25T17:05:02] [/home/dev/Projects/sync_db_cpp/_builds/_3rdParty/Hunter/toolchain] > "/usr/bin/cmake" "-DTOOLCHAIN_INFO_FILE=/home/dev/Projects/sync_db_cpp/_builds/_3rdParty/Hunter/toolchain/toolchain.info.NOLF" "-DHUNTER_SELF=/home/dev/.hunter/_Base/Download/Hunter/0.23.297/3319fe6/Unpacked" "-GUnix Makefiles" "-H/home/dev/Projects/sync_db_cpp/_builds/_3rdParty/Hunter/toolchain" "-B/home/dev/Projects/sync_db_cpp/_builds/_3rdParty/Hunter/toolchain/_builds" "-DCMAKE_MAKE_PROGRAM=/usr/bin/make" "-DCMAKE_RELEASE_POSTFIX=" "-DCMAKE_DEBUG_POSTFIX=d"
-- The C compiler identification is GNU 10.2.0
-- The CXX compiler identification is GNU 10.2.0
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/cc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /home/dev/Projects/sync_db_cpp/_builds/_3rdParty/Hunter/toolchain/_builds
-- [hunter *** DEBUG *** 2021-04-25T17:05:03] Already exists: /home/dev/.hunter/_Base/3319fe6/020aca2/toolchain.info
-- [hunter] Calculating Config-SHA1
-- [hunter *** DEBUG *** 2021-04-25T17:05:03] Cache data is up-to-date
-- [hunter] HUNTER_ROOT: /home/dev/.hunter
-- [hunter *** DEBUG *** 2021-04-25T17:05:03] HUNTER_TOOLCHAIN_ID_PATH: /home/dev/.hunter/_Base/3319fe6/020aca2
-- [hunter *** DEBUG *** 2021-04-25T17:05:03] HUNTER_CONFIGURATION_TYPES: Release;Debug
-- [hunter *** DEBUG *** 2021-04-25T17:05:03] HUNTER_BUILD_SHARED_LIBS:
-- [hunter] [ Hunter-ID: 3319fe6 | Toolchain-ID: 020aca2 | Config-ID: 65f8faa ]
-- [hunter *** DEBUG *** 2021-04-25T17:05:03] File not found (injected package): /home/dev/.hunter/_Base/Download/Hunter/0.23.297/3319fe6/Unpacked/cmake/projects/libp2p/hunter.cmake
-- [hunter *** DEBUG *** 2021-04-25T17:05:03] Injected package 'libp2p'
-- [hunter *** DEBUG *** 2021-04-25T17:05:03] libp2p versions available: []

[hunter ** INTERNAL **] Unexpected empty string
[hunter ** INTERNAL **] [Directory:/home/dev/Projects/sync_db_cpp]

------------------------------ ERROR -----------------------------
https://hunter.readthedocs.io/en/latest/reference/errors/error.internal.html

CMake Error at /home/dev/.hunter/_Base/Download/Hunter/0.23.297/3319fe6/Unpacked/cmake/modules/hunter_error_page.cmake:12 (message):
Call Stack (most recent call first):
/home/dev/.hunter/_Base/Download/Hunter/0.23.297/3319fe6/Unpacked/cmake/modules/hunter_internal_error.cmake:13 (hunter_error_page)
/home/dev/.hunter/_Base/Download/Hunter/0.23.297/3319fe6/Unpacked/cmake/modules/hunter_assert_not_empty_string.cmake:9 (hunter_internal_error)
/home/dev/.hunter/_Base/Download/Hunter/0.23.297/3319fe6/Unpacked/cmake/modules/hunter_get_package_sha1.cmake:26 (hunter_assert_not_empty_string)
/home/dev/.hunter/_Base/Download/Hunter/0.23.297/3319fe6/Unpacked/cmake/modules/hunter_download.cmake:83 (hunter_get_package_sha1)
/home/dev/.hunter/_Base/Download/Hunter/0.23.297/3319fe6/Unpacked/cmake/modules/hunter_add_package.cmake:53 (hunter_download)
CMakeLists.txt:15 (hunter_add_package)

[akash-siv]

same here.
do you find a solution?

[Ben3World]

so do I.
what is the solution?

[zach-r-hughes]

Okay, I think I (might) know what's going wrong here:

"FindOpenSSL.cmake" line ~303

Here, a regex match attempts to extract the version number from "openssl/opensslv.h".
Inside the header, it seraches for:

#define OPEN_SSL_VERSION <value>

Investigating, it appears some versions of OpenSSL (perhaps newer ones), this fails.
In my header, the "OPEN_SSL_VERSION" is defined as a combination of macros.

The regex expects something like this:
#define OPEN_SSL_VERSION 12345

However, it instead encounters this:

# define OPENSSL_VERSION_NUMBER          \
    ( (OPENSSL_VERSION_MAJOR<<28)        \
      |(OPENSSL_VERSION_MINOR<<20)       \
      |(OPENSSL_VERSION_PATCH<<4)        \
      |_OPENSSL_VERSION_PRE_RELEASE )

Consequently, the extracted version number ends up being empty.

(Note: I am using OPENSSL_VERSION_STR "3.1.3")

PS:
I've hack-fixed this locally by modifying the "opensslv.h" header via:

# define OPENSSL_VERSION_NUMBER 0x30100030L // version, in hex value
/*# define OPENSSL_VERSION_NUMBER          \
    ( (OPENSSL_VERSION_MAJOR<<28)        \
      |(OPENSSL_VERSION_MINOR<<20)       \
      |(OPENSSL_VERSION_PATCH<<4)        \
      |_OPENSSL_VERSION_PRE_RELEASE )
*/

... not the best, but it looks like things are building now.

[NikolayBlagoev]

You need to specify where it can get the version from:

Change your cmake to this:

include("cmake/HunterGate.cmake")

HunterGate(
    URL "https://github.com/cpp-pm/hunter/archive/v0.23.297.tar.gz"
    SHA1 "3319fe6a3b08090df7df98dee75134d68e2ef5a3"
    LOCAL
)
    
project(sync_db_cpp LANGUAGES CXX)
hunter_add_package(libp2p)
find_package(libp2p REQUIRED)

(add the local keyword in HunterGate to specify locally where huntergate can get the packages).

Then add a config.cmake in a Hunter folder, which should be in the same folder as your HunterGate.cmake (so cmake/Hunter/config.cmake for you) and write:

message("Loading CMAKE\n\n\n\n\n\n\n")


hunter_config(
    GTest
    VERSION 1.8.0-hunter-p11
)

hunter_config(sr25519
    URL https://github.com/Warchant/sr25519-crust/archive/1.0.1.tar.gz
    SHA1 3005d79b23b92ff27848c24a7751543a03a2dd13
    )

hunter_config(
    spdlog
    URL https://github.com/gabime/spdlog/archive/v1.4.2.zip
    SHA1 4b10e9aa17f7d568e24f464b48358ab46cb6f39c
)

hunter_config(libp2p
    URL https://github.com/libp2p/cpp-libp2p/archive/dad84a03a9651c7c2bb8a8f17d0e5ea67bd10b4f.zip
    SHA1 022162226f350942f3a4dac599058382b02ab4ef
)

This fixed it for me (might have to play with the hashes a bit, as in the SHA1 value). Also this for me fixed the issue above BUT lead me into another list of issues, which I can't even fix.