Merge pull request #244 from aminya/git-checkout [skip ci]

fix: skip or protect all mutable git or vcpkg operations to allow parallel builds

README.md

@@ -78,7 +78,6 @@ include(${_project_options_SOURCE_DIR}/Index.cmake)
 run_vcpkg(
  VCPKG_URL "https://github.com/microsoft/vcpkg.git"
  VCPKG_REV "0fa8459cf3a7caca7adc58f992bc32ff13630684"
- ENABLE_VCPKG_UPDATE
 )
 
 # Set the project name and language

src/Git.cmake

@@ -126,15 +126,18 @@ endfunction()
 
 Pull the given repository
 
-It will temporarily switch back to the previous branch if the head is detached for updating
+If ``TARGET_REVISION`` is given, the pull is skipped if the current revision is the same as the target revision.
+
+It will temporarily switch back to the previous branch if the head is detached for updating.
 
 Input variables:
 
 - ``REPOSITORY_PATH``: The path to the repository
+- ``TARGET_REVISION``: if the current revision of the repository is the same as this given revision, the pull is skipped
 
 ]]
 function(git_pull)
- set(oneValueArgs REPOSITORY_PATH)
+ set(oneValueArgs REPOSITORY_PATH TARGET_REVISION)
  cmake_parse_arguments(_fun "" "${oneValueArgs}" "" ${ARGN})
 
  if("${_fun_REPOSITORY_PATH}" STREQUAL "")
@@ -144,14 +147,30 @@ function(git_pull)
  # store the current revision
  git_revision(REVISION REPOSITORY_PATH "${_fun_REPOSITORY_PATH}")
 
+ # skip the pull if the revision is the same
+ if(NOT "${_fun_TARGET_REVISION}" STREQUAL "" AND "${REVISION}" STREQUAL "${_fun_TARGET_REVISION}")
+ message(STATUS "Skipping pull of ${_fun_REPOSITORY_PATH} because it's already at ${REVISION}")
+ return()
+ else()
+ # pull and restore it after the pull
+ set(_fun_TARGET_REVISION "${REVISION}")
+ endif()
+
  git_switch_back(REPOSITORY_PATH "${_fun_REPOSITORY_PATH}")
 
  message(STATUS "Updating ${_fun_REPOSITORY_PATH}")
  find_program(GIT_EXECUTABLE "git" REQUIRED)
- execute_process(COMMAND "${GIT_EXECUTABLE}" "pull" WORKING_DIRECTORY "${_fun_REPOSITORY_PATH}")
+
+ # wait for lock before pulling
+ git_wait(REPOSITORY_PATH "${_fun_REPOSITORY_PATH}")
+
+ execute_process(
+ COMMAND "${GIT_EXECUTABLE}" "pull" WORKING_DIRECTORY "${_fun_REPOSITORY_PATH}"
+ COMMAND_ERROR_IS_FATAL LAST
+ )
 
  # restore the revision
- git_checkout(REPOSITORY_PATH "${_fun_REPOSITORY_PATH}" REVISION "${REVISION}")
+ git_checkout(REPOSITORY_PATH "${_fun_REPOSITORY_PATH}" REVISION "${_fun_TARGET_REVISION}")
 endfunction()
 
 #[[.rst:
@@ -192,6 +211,14 @@ function(git_checkout)
  message(FATAL_ERROR "REPOSITORY_PATH and REVISION are required")
  endif()
 
+ git_revision(REVISION REPOSITORY_PATH "${_fun_REPOSITORY_PATH}")
+ if("${REVISION}" STREQUAL "${_fun_REVISION}")
+ return()
+ endif()
+
+ # wait for lock before checking out
+ git_wait(REPOSITORY_PATH "${_fun_REPOSITORY_PATH}")
+
  find_program(GIT_EXECUTABLE "git" REQUIRED)
  execute_process(
  COMMAND "${GIT_EXECUTABLE}" "-c" "advice.detachedHead=false" "checkout" "${_fun_REVISION}"
@@ -356,7 +383,7 @@ function(git_revision REVISION)
  COMMAND "${GIT_EXECUTABLE}" "rev-parse" "HEAD"
  OUTPUT_VARIABLE _git_revision
  WORKING_DIRECTORY "${_fun_REPOSITORY_PATH}"
- OUTPUT_STRIP_TRAILING_WHITESPACE
+ OUTPUT_STRIP_TRAILING_WHITESPACE COMMAND_ERROR_IS_FATAL LAST
  )
  set(${REVISION} ${_git_revision} PARENT_SCOPE)
 endfunction()
@@ -391,7 +418,7 @@ function(git_is_detached IS_DETACHED)
  COMMAND "${GIT_EXECUTABLE}" "rev-parse" "--abbrev-ref" "--symbolic-full-name" "HEAD"
  OUTPUT_VARIABLE _git_status
  WORKING_DIRECTORY "${_fun_REPOSITORY_PATH}"
- OUTPUT_STRIP_TRAILING_WHITESPACE
+ OUTPUT_STRIP_TRAILING_WHITESPACE COMMAND_ERROR_IS_FATAL LAST
  )
  if("${_git_status}" STREQUAL "HEAD")
  set(${IS_DETACHED} TRUE PARENT_SCOPE)
@@ -424,9 +451,23 @@ function(git_switch_back)
 
  if(${IS_DETACHED})
  message(STATUS "Switch back ${_fun_REPOSITORY_PATH}")
+
+ # wait for lock before switching back
+ git_wait(REPOSITORY_PATH "${_fun_REPOSITORY_PATH}")
+
  execute_process(
  COMMAND "${GIT_EXECUTABLE}" "switch" "-" WORKING_DIRECTORY "${_fun_REPOSITORY_PATH}"
+ RESULT_VARIABLE _switch_back_result
  )
+
+ # if the switch back failed, try to checkout the previous branch
+ if(NOT ${_switch_back_result} EQUAL 0)
+ message(STATUS "Switch back failed. Trying to checkout previous branch")
+ execute_process(
+ COMMAND "${GIT_EXECUTABLE}" "checkout" "-" WORKING_DIRECTORY "${_fun_REPOSITORY_PATH}"
+ COMMAND_ERROR_IS_FATAL LAST
+ )
+ endif()
  endif()
 endfunction()
 
@@ -457,20 +498,17 @@ function(git_wait)
 
  set(counter 0)
 
- message(STATUS "Waiting for git lock file...[${counter}/${_fun_TIMEOUT_COUNTER}]")
-
  # wait until .git/index is present (in case a parallel clone is running)
  while(NOT EXISTS "${_fun_REPOSITORY_PATH}/.git/index"
  OR EXISTS "${_fun_REPOSITORY_PATH}/.git/index.lock"
  )
- execute_process(COMMAND ${CMAKE_COMMAND} -E sleep 0.5)
+ message(STATUS "Waiting for git lock file...[${counter}/${_fun_TIMEOUT_COUNTER}]")
+ execute_process(COMMAND ${CMAKE_COMMAND} -E sleep 0.5 COMMAND_ERROR_IS_FATAL LAST)
 
  math(EXPR counter "${counter} + 1")
  if(${counter} GREATER ${_fun_TIMEOUT_COUNTER})
  message(STATUS "Timeout waiting for git lock file. Continuing...")
  return()
- else()
- message(STATUS "Waiting for git lock file...[${counter}/${_fun_TIMEOUT_COUNTER}]")
  endif()
  endwhile()
 endfunction()

src/Vcpkg.cmake

@@ -29,7 +29,7 @@ endmacro()
 
 macro(_update_vcpkg_repository)
  if(${_vcpkg_args_ENABLE_VCPKG_UPDATE})
- git_pull(REPOSITORY_PATH "${_vcpkg_args_VCPKG_DIR}")
+ git_pull(REPOSITORY_PATH "${_vcpkg_args_VCPKG_DIR}" TARGET_REVISION "${_vcpkg_args_VCPKG_REV}")
  endif()
 endmacro()
 
@@ -94,7 +94,6 @@ endmacro()
 
 macro(_checkout_vcpkg_repository)
  if(NOT "${_vcpkg_args_VCPKG_REV}" STREQUAL "")
-
  git_checkout(REPOSITORY_PATH "${_vcpkg_args_VCPKG_DIR}" REVISION "${_vcpkg_args_VCPKG_REV}")
  endif()
 endmacro()