From 58f152a92a0fa3ad6d5f0fcf64501b1108097c69 Mon Sep 17 00:00:00 2001
From: Dan Liew <daniel.liew@imperial.ac.uk>
Date: Wed, 23 Aug 2017 19:21:32 +0100
Subject: [PATCH] [CMake] Teach CMake to support git worktrees. This fixes the
bug reported by @nbraud reported in #1227.
Previously the CMake build system assumed that the `.git` file must
be a directory. This is not the case when the working directory
is a "git worktree". In this case the `.git` file is just a plain
file that points to a directory within the true `.git` directory.
This commit essentially implements the logic to traverse this extra
level of indirection and removes some assumptions that the `.git`
file is a directory.
---
cmake/git_utils.cmake | 82 ++++++++++++++++++++++++++++++-------------
1 file changed, 58 insertions(+), 24 deletions(-)
diff --git a/cmake/git_utils.cmake b/cmake/git_utils.cmake
index f98aca205..dbc95d8df 100644
--- a/cmake/git_utils.cmake
+++ b/cmake/git_utils.cmake
@@ -4,23 +4,55 @@
# of the git directory changes CMake will be forced to re-run. This useful
# for fetching the current git hash and including it in the build.
#
-# `GIT_DIR` is the path to the git directory (i.e. the `.git` directory)
+# `GIT_DOT_FILE` is the path to the git directory (i.e. the `.git` directory) or
+# `.git` file used by a git worktree.
# `SUCCESS_VAR` is the name of the variable to set. It will be set to TRUE
# if the dependency was successfully added and FALSE otherwise.
-function(add_git_dir_dependency GIT_DIR SUCCESS_VAR)
+function(add_git_dir_dependency GIT_DOT_FILE SUCCESS_VAR)
if (NOT "${ARGC}" EQUAL 2)
message(FATAL_ERROR "Invalid number (${ARGC}) of arguments")
endif()
- if (NOT IS_ABSOLUTE "${GIT_DIR}")
- message(FATAL_ERROR "GIT_DIR (\"${GIT_DIR}\") is not an absolute path")
+ if (NOT IS_ABSOLUTE "${GIT_DOT_FILE}")
+ message(FATAL_ERROR "GIT_DOT_FILE (\"${GIT_DOT_FILE}\") is not an absolute path")
endif()
- if (NOT IS_DIRECTORY "${GIT_DIR}")
- message(FATAL_ERROR "GIT_DIR (\"${GIT_DIR}\") is not a directory")
+ if (NOT EXISTS "${GIT_DOT_FILE}")
+ message(FATAL_ERROR "GIT_DOT_FILE (\"${GIT_DOT_FILE}\") does not exist")
endif()
- set(GIT_HEAD_FILE "${GIT_DIR}/HEAD")
+ if (NOT IS_DIRECTORY "${GIT_DOT_FILE}")
+ # Might be a git worktree. In this case we need parse out the worktree
+ # git directory
+ file(READ "${GIT_DOT_FILE}" GIT_DOT_FILE_DATA LIMIT 512)
+ string(STRIP "${GIT_DOT_FILE_DATA}" GIT_DOT_FILE_DATA_STRIPPED)
+ if ("${GIT_DOT_FILE_DATA_STRIPPED}" MATCHES "^gitdir:[ ]*(.+)$")
+ # Git worktree
+ message(STATUS "Found git worktree")
+ set(GIT_WORKTREE_DIR "${CMAKE_MATCH_1}")
+ set(GIT_HEAD_FILE "${GIT_WORKTREE_DIR}/HEAD")
+ # Figure out where real git directory lives
+ set(GIT_COMMON_DIR_FILE "${GIT_WORKTREE_DIR}/commondir")
+ if (NOT EXISTS "${GIT_COMMON_DIR_FILE}")
+ message(FATAL_ERROR "Found git worktree dir but could not find \"${GIT_COMMON_DIR_FILE}\"")
+ endif()
+ file(READ "${GIT_COMMON_DIR_FILE}" GIT_COMMON_DIR_FILE_DATA LIMIT 512)
+ string(STRIP "${GIT_COMMON_DIR_FILE_DATA}" GIT_COMMON_DIR_FILE_DATA_STRIPPED)
+ get_filename_component(GIT_DIR "${GIT_WORKTREE_DIR}/${GIT_COMMON_DIR_FILE_DATA_STRIPPED}" ABSOLUTE)
+ if (NOT IS_DIRECTORY "${GIT_DIR}")
+ message(FATAL_ERROR "Failed to compute path to git directory from git worktree")
+ endif()
+ else()
+ message(FATAL_ERROR "GIT_DOT_FILE (\"${GIT_DOT_FILE}\") is not a directory or a pointer to git worktree directory")
+ endif()
+ else()
+ # Just a normal `.git` directory
+ message(STATUS "Found simple git working directory")
+ set(GIT_HEAD_FILE "${GIT_DOT_FILE}/HEAD")
+ set(GIT_DIR "${GIT_DOT_FILE}")
+ endif()
+ message(STATUS "Found git directory \"${GIT_DIR}\"")
+
if (NOT EXISTS "${GIT_HEAD_FILE}")
message(AUTHOR_WARNING "Git head file \"${GIT_HEAD_FILE}\" cannot be found")
set(${SUCCESS_VAR} FALSE PARENT_SCOPE)
@@ -79,24 +111,25 @@ function(add_git_dir_dependency GIT_DIR SUCCESS_VAR)
set(${SUCCESS_VAR} TRUE PARENT_SCOPE)
endfunction()
-# get_git_head_hash(GIT_DIR OUTPUT_VAR)
+# get_git_head_hash(GIT_DOT_FILE OUTPUT_VAR)
#
-# Retrieve the current commit hash for a git working directory where `GIT_DIR`
-# is the `.git` directory in the root of the git working directory.
+# Retrieve the current commit hash for a git working directory where
+# `GIT_DOT_FILE` is the `.git` directory or `.git` pointer file in a git
+# worktree in the root of the git working directory.
#
# `OUTPUT_VAR` should be the name of the variable to put the result in. If this
# function fails then either a fatal error will be raised or `OUTPUT_VAR` will
# contain a string with the suffix `NOTFOUND` which can be used in CMake `if()`
# commands.
-function(get_git_head_hash GIT_DIR OUTPUT_VAR)
+function(get_git_head_hash GIT_DOT_FILE OUTPUT_VAR)
if (NOT "${ARGC}" EQUAL 2)
message(FATAL_ERROR "Invalid number of arguments")
endif()
- if (NOT IS_DIRECTORY "${GIT_DIR}")
- message(FATAL_ERROR "\"${GIT_DIR}\" is not a directory")
+ if (NOT EXISTS "${GIT_DOT_FILE}")
+ message(FATAL_ERROR "\"${GIT_DOT_FILE}\" does not exist")
endif()
- if (NOT IS_ABSOLUTE "${GIT_DIR}")
- message(FATAL_ERROR \""${GIT_DIR}\" is not an absolute path")
+ if (NOT IS_ABSOLUTE "${GIT_DOT_FILE}")
+ message(FATAL_ERROR \""${GIT_DOT_FILE}\" is not an absolute path")
endif()
find_package(Git)
# NOTE: Use `GIT_FOUND` rather than `Git_FOUND` which was only
@@ -105,7 +138,7 @@ function(get_git_head_hash GIT_DIR OUTPUT_VAR)
set(${OUTPUT_VAR} "GIT-NOTFOUND" PARENT_SCOPE)
return()
endif()
- get_filename_component(GIT_WORKING_DIR "${GIT_DIR}" DIRECTORY)
+ get_filename_component(GIT_WORKING_DIR "${GIT_DOT_FILE}" DIRECTORY)
execute_process(
COMMAND
"${GIT_EXECUTABLE}"
@@ -128,24 +161,25 @@ function(get_git_head_hash GIT_DIR OUTPUT_VAR)
set(${OUTPUT_VAR} "${Z3_GIT_HASH}" PARENT_SCOPE)
endfunction()
-# get_git_head_describe(GIT_DIR OUTPUT_VAR)
+# get_git_head_describe(GIT_DOT_FILE OUTPUT_VAR)
#
# Retrieve the output of `git describe` for a git working directory where
-# `GIT_DIR` is the `.git` directory in the root of the git working directory.
+# `GIT_DOT_FILE` is the `.git` directory or `.git` pointer file in a git
+# worktree in the root of the git working directory.
#
# `OUTPUT_VAR` should be the name of the variable to put the result in. If this
# function fails then either a fatal error will be raised or `OUTPUT_VAR` will
# contain a string with the suffix `NOTFOUND` which can be used in CMake `if()`
# commands.
-function(get_git_head_describe GIT_DIR OUTPUT_VAR)
+function(get_git_head_describe GIT_DOT_FILE OUTPUT_VAR)
if (NOT "${ARGC}" EQUAL 2)
message(FATAL_ERROR "Invalid number of arguments")
endif()
- if (NOT IS_DIRECTORY "${GIT_DIR}")
- message(FATAL_ERROR "\"${GIT_DIR}\" is not a directory")
+ if (NOT EXISTS "${GIT_DOT_FILE}")
+ message(FATAL_ERROR "\"${GIT_DOT_FILE}\" does not exist")
endif()
- if (NOT IS_ABSOLUTE "${GIT_DIR}")
- message(FATAL_ERROR \""${GIT_DIR}\" is not an absolute path")
+ if (NOT IS_ABSOLUTE "${GIT_DOT_FILE}")
+ message(FATAL_ERROR \""${GIT_DOT_FILE}\" is not an absolute path")
endif()
find_package(Git)
# NOTE: Use `GIT_FOUND` rather than `Git_FOUND` which was only
@@ -154,7 +188,7 @@ function(get_git_head_describe GIT_DIR OUTPUT_VAR)
set(${OUTPUT_VAR} "GIT-NOTFOUND" PARENT_SCOPE)
return()
endif()
- get_filename_component(GIT_WORKING_DIR "${GIT_DIR}" DIRECTORY)
+ get_filename_component(GIT_WORKING_DIR "${GIT_DOT_FILE}" DIRECTORY)
execute_process(
COMMAND
"${GIT_EXECUTABLE}"