Fix race condition between hack and hack_ffi targets

Summary:
We use `hphp/hack/dev_env.sh` to set up various environment variables for
OCaml and Rust compilation; this ends with `eval $(opam env)`.

It turns out that if you try to run `opam env` while another instance of `opam` is running, the output is:

```
Another process has locked /Users/fredemmott/code/hhvm/build/hphp/hack/opam/hack-switch/.opam-switch/lock, waiting (C-c to abort)... lock acquired. OPAM_SWITCH_PREFIX=...... normal output here
```

... which can't be evaled.

This happens when doing a parallel build as both the `hack` (typechecker) and `hack_ffi` (rust stuff, both for the typechecker and hackc embedded in HHVM) targets use dev_env.sh

Fix this by splitting out a `dev_env_common.sh.in` and a `dev_env_rust_only.sh.in`, and making the `hack_ffi` target use the `dev_env_rust_only.sh`

CMake generates the `.sh` from the `.sh.in`

Reviewed By: kavoor

Differential Revision: D30583055

fbshipit-source-id: 0770bfc6528db15dd455398567f3d31beaed37c3

hphp/hack/CMakeLists.txt

@@ -124,7 +124,7 @@ set(CARGO_BUILD "${CMAKE_SOURCE_DIR}/hphp/hack/scripts/build_rust_to_ocaml.sh")
 add_custom_target(
   hack_ffi
   COMMAND
-   . "${CMAKE_CURRENT_BINARY_DIR}/dev_env.sh" &&
+   . "${CMAKE_CURRENT_BINARY_DIR}/dev_env_rust_only.sh" &&
     ${CARGO_BUILD} hack_parser_ffi rust_parser_ffi &&
     ${CARGO_BUILD} rust_facts_ffi rust_facts_ffi &&
     ${CARGO_BUILD} compile_ffi compile_ffi &&
@@ -185,6 +185,8 @@ add_dependencies(libdecl_cpp_ffi_stubs hack_ffi)
 set_target_properties(libdecl_cpp_ffi_stubs PROPERTIES IMPORTED_LOCATION ${LIBRUST_DECL_PATH})
 
 configure_file(dev_env.sh.in dev_env.sh ESCAPE_QUOTES @ONLY)
+configure_file(dev_env_common.sh.in dev_env_common.sh ESCAPE_QUOTES @ONLY)
+configure_file(dev_env_rust_only.sh.in dev_env_rust_only.sh ESCAPE_QUOTES @ONLY)
 
 install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/bin/hh_client
   DESTINATION bin

hphp/hack/dev_env.sh.in

@@ -1,4 +1,3 @@
-#!/bin/sh
 # Copyright (c) 2019, Facebook, Inc.
 # All rights reserved.
 #
@@ -11,24 +10,5 @@
 #
 #  source $BUILD_DIR/hphp/hack/dev_env.sh
 
-export CMAKE_SOURCE_DIR="@CMAKE_SOURCE_DIR@"
-export CMAKE_INSTALL_FULL_SYSCONFDIR="@CMAKE_INSTALL_FULL_SYSCONFDIR@"
-export CMAKE_INSTALL_FULL_BINDIR="@CMAKE_INSTALL_FULL_BINDIR@"
-
-export HACK_NO_CARGO_VENDOR=true
-export OPAMROOT="@OPAMROOT@"
-export PYTHONPATH="@HPHP_HOME@" # needed for verify.py for `hack_dune_test`
-export CARGO_HOME="@CMAKE_CURRENT_BINARY_DIR@/cargo_home"
-export RUSTC="@RUSTC_BIN_DIR@/rustc"
-export DUNE_BUILD_DIR="@DUNE_BUILD_DIR@"
-export HACK_SOURCE_ROOT="@CMAKE_CURRENT_SOURCE_DIR@"
-export HACK_BUILD_ROOT="@HACK_BUILD_ROOT@"
-export HACK_BIN_DIR="@CMAKE_BINARY_DIR@/hphp/hack/bin"
-export PATH="@RUSTC_BIN_DIR@:@CARGO_BIN_DIR@:$(dirname "@OPAM_EXECUTABLE@"):$PATH"
-
-export HACK_EXTRA_INCLUDE_PATHS="@extra_include_paths@"
-export HACK_EXTRA_LINK_OPTS="@extra_link_opts@"
-export HACK_EXTRA_LIB_PATHS="@extra_lib_paths@"
-export HACK_EXTRA_NATIVE_LIBRARIES="@extra_native_libraries@"
-
+. "@CMAKE_CURRENT_BINARY_DIR@/dev_env_common.sh"
 eval $(opam env)

hphp/hack/dev_env_common.sh.in

@@ -0,0 +1,28 @@
+#!/bin/sh
+# Copyright (c) 2019, Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the "hack" directory of this source tree.
+
+# Do not use this file directly - either use dev_env.sh or dev_env_rust_only.sh
+
+export CMAKE_SOURCE_DIR="@CMAKE_SOURCE_DIR@"
+export CMAKE_INSTALL_FULL_SYSCONFDIR="@CMAKE_INSTALL_FULL_SYSCONFDIR@"
+export CMAKE_INSTALL_FULL_BINDIR="@CMAKE_INSTALL_FULL_BINDIR@"
+
+export HACK_NO_CARGO_VENDOR=true
+export OPAMROOT="@OPAMROOT@"
+export PYTHONPATH="@HPHP_HOME@" # needed for verify.py for `hack_dune_test`
+export CARGO_HOME="@CMAKE_CURRENT_BINARY_DIR@/cargo_home"
+export RUSTC="@RUSTC_BIN_DIR@/rustc"
+export DUNE_BUILD_DIR="@DUNE_BUILD_DIR@"
+export HACK_SOURCE_ROOT="@CMAKE_CURRENT_SOURCE_DIR@"
+export HACK_BUILD_ROOT="@HACK_BUILD_ROOT@"
+export HACK_BIN_DIR="@CMAKE_BINARY_DIR@/hphp/hack/bin"
+export PATH="@RUSTC_BIN_DIR@:@CARGO_BIN_DIR@:$(dirname "@OPAM_EXECUTABLE@"):$PATH"
+
+export HACK_EXTRA_INCLUDE_PATHS="@extra_include_paths@"
+export HACK_EXTRA_LINK_OPTS="@extra_link_opts@"
+export HACK_EXTRA_LIB_PATHS="@extra_lib_paths@"
+export HACK_EXTRA_NATIVE_LIBRARIES="@extra_native_libraries@"

hphp/hack/dev_env_rust_only.sh.in

@@ -0,0 +1,14 @@
+# Copyright (c) 2019, Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the "hack" directory of this source tree.
+
+# This file is processed by cmake; the produced file is intended for both
+# internal usage by the build system, and for direct usage by people working on
+# Hack itself from CMake builds:
+#
+#  . $BUILD_DIR/hphp/hack/dev_env_rust_only.sh
+
+. "@CMAKE_CURRENT_BINARY_DIR@/dev_env_common.sh"
+# Nothing else to do for rust :)