Revert "libgit2: 0.26.6 → 0.27.7"

This reverts commit cc506381761d84bd0047cabba7151ad516fa8a32 because
it breaks cargo (again, see fca4fbeba957ec6bc72c98c019bbc5f01712d15b):

  $ cargo build
      Updating crates.io index
  Segmentation fault

5 files changed, 57 insertions, 14 deletions

diff --git a/pkgs/applications/version-management/git-and-tools/grv/default.nix b/pkgs/applications/version-management/git-and-tools/grv/default.nix
index c70f6996529..1119c9a5b4c 100644
--- a/pkgs/applications/version-management/git-and-tools/grv/default.nix
+++ b/pkgs/applications/version-management/git-and-tools/grv/default.nix
@@ -1,11 +1,11 @@
-{ stdenv, buildGo19Package, fetchFromGitHub, curl, libgit2, ncurses, pkgconfig, readline }:
+{ stdenv, buildGo19Package, fetchFromGitHub, curl, libgit2_0_27, ncurses, pkgconfig, readline }:
 let
   version = "0.3.1";
 in
 buildGo19Package {
   name = "grv-${version}";
 
-  buildInputs = [ ncurses readline curl libgit2 ];
+  buildInputs = [ ncurses readline curl libgit2_0_27 ];
   nativeBuildInputs = [ pkgconfig ];
 
   goPackagePath = "github.com/rgburke/grv";
diff --git a/pkgs/development/libraries/git2/0.27.nix b/pkgs/development/libraries/git2/0.27.nix
new file mode 100644
index 00000000000..93948a1b0d6
--- /dev/null
+++ b/pkgs/development/libraries/git2/0.27.nix
@@ -0,0 +1,36 @@
+{ stdenv, fetchFromGitHub, cmake, pkgconfig, python
+, zlib, libssh2, openssl, http-parser, curl
+, libiconv, Security
+}:
+
+stdenv.mkDerivation rec {
+  version = "0.27.7";
+  name = "libgit2-${version}";
+
+  src = fetchFromGitHub {
+    owner = "libgit2";
+    repo = "libgit2";
+    rev = "v${version}";
+    sha256 = "1q3mp7xjpbmdsnk4sdzf2askbb4pgbxcmr1h7y7zk2738dndwkha";
+  };
+
+  cmakeFlags = [ "-DTHREADSAFE=ON" ];
+
+  nativeBuildInputs = [ cmake python pkgconfig ];
+
+  buildInputs = [ zlib libssh2 openssl http-parser curl ]
+    ++ stdenv.lib.optional stdenv.isDarwin Security;
+
+  propagatedBuildInputs = stdenv.lib.optional (!stdenv.isLinux) libiconv;
+
+  enableParallelBuilding = true;
+
+  doCheck = false; # hangs. or very expensive?
+
+  meta = {
+    description = "The Git linkable library";
+    homepage = https://libgit2.github.com/;
+    license = stdenv.lib.licenses.gpl2;
+    platforms = with stdenv.lib.platforms; all;
+  };
+}
diff --git a/pkgs/development/libraries/git2/default.nix b/pkgs/development/libraries/git2/default.nix
index ec610d1e565..358fc31fc80 100644
--- a/pkgs/development/libraries/git2/default.nix
+++ b/pkgs/development/libraries/git2/default.nix
@@ -1,18 +1,18 @@
-{ stdenv, fetchFromGitHub, cmake, pkgconfig, python
-, zlib, libssh2, openssl, http-parser, curl
+{ stdenv, fetchFromGitHub, pkgconfig, cmake
+, zlib, python, libssh2, openssl, curl, http-parser
 , libiconv, Security
 }:
 
-stdenv.mkDerivation rec {
-  pname = "libgit2";
-  version = "0.27.7";
+stdenv.mkDerivation (rec {
+  name = "libgit2-${version}";
+  version = "0.26.6";
   # keep the version in sync with pythonPackages.pygit2 and libgit2-glib
 
   src = fetchFromGitHub {
     owner = "libgit2";
     repo = "libgit2";
     rev = "v${version}";
-    sha256 = "1q3mp7xjpbmdsnk4sdzf2askbb4pgbxcmr1h7y7zk2738dndwkha";
+    sha256 = "17pjvprmdrx4h6bb1hhc98w9qi6ki7yl57f090n9kbhswxqfs7s3";
   };
 
   cmakeFlags = [ "-DTHREADSAFE=ON" ];
@@ -22,7 +22,7 @@ stdenv.mkDerivation rec {
   buildInputs = [ zlib libssh2 openssl http-parser curl ]
     ++ stdenv.lib.optional stdenv.isDarwin Security;
 
-  propagatedBuildInputs = stdenv.lib.optional (!stdenv.isLinux) libiconv;
+  propagatedBuildInputs = stdenv.lib.optional (!stdenv.isLinux) [ libiconv ];
 
   enableParallelBuilding = true;
 
@@ -34,4 +34,5 @@ stdenv.mkDerivation rec {
     license = licenses.gpl2;
     platforms = with platforms; all;
   };
-}
+} // stdenv.lib.optionalAttrs (!stdenv.isLinux) {
+})
diff --git a/pkgs/development/python-modules/pygit2/default.nix b/pkgs/development/python-modules/pygit2/default.nix
index 313a3e5ab18..2334e4a3431 100644
--- a/pkgs/development/python-modules/pygit2/default.nix
+++ b/pkgs/development/python-modules/pygit2/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, lib, buildPythonPackage, fetchPypi, fetchpatch, isPyPy, libgit2, six, cffi }:
+{ stdenv, lib, buildPythonPackage, fetchPypi, fetchpatch, isPyPy, libgit2_0_27, six, cffi }:
 
 buildPythonPackage rec {
   pname = "pygit2";
@@ -10,7 +10,7 @@ buildPythonPackage rec {
   };
 
   preConfigure = lib.optionalString stdenv.isDarwin ''
-    export DYLD_LIBRARY_PATH="${libgit2}/lib"
+    export DYLD_LIBRARY_PATH="${libgit2_0_27}/lib"
   '';
 
   patches = [ (fetchpatch {
@@ -19,7 +19,7 @@ buildPythonPackage rec {
     sha256 = "18x1fpmywhjjr4lvakwmy34zpxfqi8pqqj48g1wcib39lh3s7l4f";
   }) ];
 
-  propagatedBuildInputs = [ libgit2 six ] ++ lib.optional (!isPyPy) cffi;
+  propagatedBuildInputs = [ libgit2_0_27 six ] ++ lib.optional (!isPyPy) cffi;
 
   preCheck = ''
     # disable tests that require networking
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 8b0c213d378..0f2ed083a28 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -1007,7 +1007,9 @@ in
 
   blockdiag = with python3Packages; toPythonApplication blockdiag;
 
-  blsd = callPackage ../tools/misc/blsd { };
+  blsd = callPackage ../tools/misc/blsd {
+    libgit2 = libgit2_0_27;
+  };
 
   bluez-alsa = callPackage ../tools/bluetooth/bluez-alsa { };
 
@@ -9919,6 +9921,10 @@ in
     inherit (darwin.apple_sdk.frameworks) Security;
   };
 
+  libgit2_0_27 = callPackage ../development/libraries/git2/0.27.nix {
+    inherit (darwin.apple_sdk.frameworks) Security;
+  };
+
   libgit2-glib = callPackage ../development/libraries/libgit2-glib { };
 
   glbinding = callPackage ../development/libraries/glbinding { };