Introduce automatic semantic versioning

version.cmake

@@ -1,16 +1,153 @@
-file(STRINGS "${CMAKE_CURRENT_SOURCE_DIR}/VERSION" version_lines)
+get_filename_component(VERSION_CMAKE_DIR "${CMAKE_CURRENT_LIST_FILE}" DIRECTORY)
+
+set(VERSION_FILE "${VERSION_CMAKE_DIR}/VERSION")
+
+file(STRINGS "${VERSION_FILE}" version_lines)
 foreach(line ${version_lines})
     if(line MATCHES "^VERSION_MAJOR = (.*)$")
-        set(VERSION_MAJOR ${CMAKE_MATCH_1})
+        set(VERSION_MAJOR "${CMAKE_MATCH_1}")
     elseif(line MATCHES "^VERSION_MINOR = (.*)$")
-        set(VERSION_MINOR ${CMAKE_MATCH_1})
+        set(VERSION_MINOR "${CMAKE_MATCH_1}")
     elseif(line MATCHES "^PATCHLEVEL = (.*)$")
-        set(VERSION_PATCH ${CMAKE_MATCH_1})
+        set(VERSION_PATCH "${CMAKE_MATCH_1}")
+    elseif(line MATCHES "^VERSION_TWEAK = (.*)$")
+        set(VERSION_TWEAK "${CMAKE_MATCH_1}")
+    elseif(line MATCHES "^EXTRAVERSION = (.*)$")
+        set(VERSION_EXTRA "${CMAKE_MATCH_1}")
+    endif()
+endforeach()
+
+foreach(required_var VERSION_MAJOR VERSION_MINOR VERSION_PATCH)
+    if(NOT DEFINED ${required_var})
+        message(FATAL_ERROR "Missing ${required_var} in ${VERSION_FILE}")
     endif()
 endforeach()
 
+set(FIRMWARE_BASE_VERSION "${VERSION_MAJOR}.${VERSION_MINOR}.${VERSION_PATCH}")
+if(DEFINED VERSION_TWEAK AND NOT VERSION_TWEAK STREQUAL "" AND NOT VERSION_TWEAK STREQUAL "0")
+    string(APPEND FIRMWARE_BASE_VERSION ".${VERSION_TWEAK}")
+endif()
+if(DEFINED VERSION_EXTRA AND NOT VERSION_EXTRA STREQUAL "")
+    string(APPEND FIRMWARE_BASE_VERSION "${VERSION_EXTRA}")
+endif()
+
+set(FIRMWARE_VERSION "${FIRMWARE_BASE_VERSION}")
+
+function(openearable_resolve_git_dir out_var)
+    set(git_path "${VERSION_CMAKE_DIR}/.git")
+
+    if(IS_DIRECTORY "${git_path}")
+        set(${out_var} "${git_path}" PARENT_SCOPE)
+        return()
+    endif()
+
+    if(EXISTS "${git_path}")
+        file(READ "${git_path}" git_dir_contents)
+        string(REGEX MATCH "gitdir: (.+)" _ "${git_dir_contents}")
+        if(CMAKE_MATCH_1)
+            set(parsed_git_dir "${CMAKE_MATCH_1}")
+            if(IS_ABSOLUTE "${parsed_git_dir}")
+                set(resolved_git_dir "${parsed_git_dir}")
+            else()
+                set(resolved_git_dir "${VERSION_CMAKE_DIR}/${parsed_git_dir}")
+            endif()
+            file(TO_CMAKE_PATH "${resolved_git_dir}" resolved_git_dir)
+            set(${out_var} "${resolved_git_dir}" PARENT_SCOPE)
+        endif()
+    endif()
+endfunction()
+
+function(openearable_track_git_state git_dir)
+    if(NOT git_dir OR NOT EXISTS "${git_dir}/HEAD")
+        return()
+    endif()
+
+    set_property(
+        DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS
+        "${git_dir}/HEAD"
+        "${git_dir}/index"
+        "${git_dir}/packed-refs"
+    )
+
+    file(READ "${git_dir}/HEAD" git_head)
+    string(STRIP "${git_head}" git_head)
+    if(git_head MATCHES "^ref: (.+)$")
+        set_property(
+            DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS
+            "${git_dir}/${CMAKE_MATCH_1}"
+        )
+    endif()
+endfunction()
+
+function(openearable_resolve_pr_suffix out_var)
+    set(pr_number "")
+
+    if(DEFINED ENV{GITHUB_EVENT_NAME} AND "$ENV{GITHUB_EVENT_NAME}" STREQUAL "pull_request")
+        if(DEFINED ENV{GITHUB_REF} AND "$ENV{GITHUB_REF}" MATCHES "^refs/pull/([0-9]+)/")
+            set(pr_number "${CMAKE_MATCH_1}")
+        elseif(DEFINED ENV{GITHUB_HEAD_REF} AND DEFINED ENV{GITHUB_REF_NAME} AND
+               "$ENV{GITHUB_REF_NAME}" MATCHES "^([0-9]+)/")
+            set(pr_number "${CMAKE_MATCH_1}")
+        endif()
+    endif()
+
+    if(pr_number STREQUAL "" AND DEFINED ENV{SYSTEM_PULLREQUEST_PULLREQUESTNUMBER})
+        set(pr_number "$ENV{SYSTEM_PULLREQUEST_PULLREQUESTNUMBER}")
+    endif()
+
+    if(pr_number STREQUAL "" AND DEFINED ENV{CHANGE_ID})
+        set(pr_number "$ENV{CHANGE_ID}")
+    endif()
+
+    if(pr_number STREQUAL "")
+        set(${out_var} "" PARENT_SCOPE)
+    else()
+        set(${out_var} "-pr${pr_number}" PARENT_SCOPE)
+    endif()
+endfunction()
+
+find_package(Git QUIET)
+openearable_resolve_pr_suffix(PR_SUFFIX)
+if(GIT_FOUND)
+    openearable_resolve_git_dir(PROJECT_GIT_DIR)
+    if(PROJECT_GIT_DIR)
+        openearable_track_git_state("${PROJECT_GIT_DIR}")
+
+        execute_process(
+            COMMAND "${GIT_EXECUTABLE}" -C "${VERSION_CMAKE_DIR}" describe --tags --long --dirty --match "v[0-9]*"
+            OUTPUT_VARIABLE git_describe
+            OUTPUT_STRIP_TRAILING_WHITESPACE
+            RESULT_VARIABLE git_describe_result
+            ERROR_QUIET
+        )
+
+        if(git_describe_result EQUAL 0 AND
+           git_describe MATCHES "^v([0-9]+\\.[0-9]+\\.[0-9]+(\\.[0-9]+)?)(-[0-9A-Za-z.-]+)?-([0-9]+)-(g[0-9a-f]+)(-dirty)?$")
+            set(GIT_TAG_VERSION "${CMAKE_MATCH_1}${CMAKE_MATCH_3}")
+            set(GIT_COMMITS_SINCE_TAG "${CMAKE_MATCH_4}")
+            set(GIT_SHORT_SHA "${CMAKE_MATCH_5}")
+            set(GIT_DIRTY_SUFFIX "${CMAKE_MATCH_6}")
+
+            if(GIT_COMMITS_SINCE_TAG EQUAL 0 AND GIT_DIRTY_SUFFIX STREQUAL "")
+                set(FIRMWARE_VERSION "${GIT_TAG_VERSION}${PR_SUFFIX}")
+            else()
+                set(FIRMWARE_VERSION "${GIT_TAG_VERSION}-dev.${GIT_COMMITS_SINCE_TAG}${PR_SUFFIX}+${GIT_SHORT_SHA}")
+                if(NOT GIT_DIRTY_SUFFIX STREQUAL "")
+                    string(APPEND FIRMWARE_VERSION ".dirty")
+                endif()
+            endif()
+        endif()
+    endif()
+endif()
+
+if(PR_SUFFIX AND FIRMWARE_VERSION STREQUAL FIRMWARE_BASE_VERSION)
+    set(FIRMWARE_VERSION "${FIRMWARE_VERSION}${PR_SUFFIX}")
+endif()
+
+message(STATUS "Firmware version: ${FIRMWARE_VERSION}")
+
 configure_file(
-    ${CMAKE_CURRENT_SOURCE_DIR}/version.h.in
-    ${CMAKE_CURRENT_BINARY_DIR}/include/generated/version.h
+    "${VERSION_CMAKE_DIR}/version.h.in"
+    "${CMAKE_CURRENT_BINARY_DIR}/include/generated/version.h"
     @ONLY
 )

version.h.in

@@ -1,6 +1,6 @@
 #ifndef VERSION_H
 #define VERSION_H
 
-#define FIRMWARE_VERSION "@VERSION_MAJOR@.@VERSION_MINOR@.@VERSION_PATCH@"
+#define FIRMWARE_VERSION "@FIRMWARE_VERSION@"
 
 #endif /* VERSION_H */