versions string, again

Author: mhekkel

cmake/VersionString.cmake

@@ -39,7 +39,7 @@ cmake_minimum_required(VERSION 3.15)
 
 	write_version_header(<destdir>
 	                     [FILE_NAME <file-name>]
-						 [VAR_PREFIX <prefix>]
+						 [LIB_NAME <library-name>]
 	                    )
   
   This command will generate the code to write a file name
@@ -48,9 +48,9 @@ cmake_minimum_required(VERSION 3.15)
   ``FILE_NAME``
 	Specify the name of the file to create, default is ``revision.hpp``.
 
-  ``VAR_PREFIX``
-	Specify a prefix part for the variables contained in the revision
-	file.
+  ``LIB_NAME``
+	Specify the library name which will be used as a prefix part for the
+	variables contained in the revision file.
 #]=======================================================================]
 
 # First locate a .git file or directory.
@@ -199,7 +199,7 @@ endfunction()
 function(write_version_header dir)
 
 	set(flags )
-	set(options VAR_PREFIX FILE_NAME)
+	set(options LIB_NAME FILE_NAME)
 	set(sources )
 	cmake_parse_arguments(VERSION_STRING_OPTION "${flags}" "${options}" "${sources}" ${ARGN})
 
@@ -255,73 +255,79 @@ function(write_version_header dir)
 		set(REVISION_DATE_TIME "")
 	endif()
 
-	if(VERSION_STRING_OPTION_VAR_PREFIX)
-		set(VAR_PREFIX "${VERSION_STRING_OPTION_VAR_PREFIX}")
+	if(VERSION_STRING_OPTION_LIB_NAME)
+		set(VAR_PREFIX "${VERSION_STRING_OPTION_LIB_NAME}")
+		set(IDENT_PREFIX "${VERSION_STRING_OPTION_LIB_NAME}_")
+	else()
+		set(VAR_PREFIX "")
+		set(IDENT_PREFIX "")
 	endif()
 
-	file(WRITE "${VERSION_STRING_DATA}/${file_name}.in" [[
-
-
-// Generated revision file
+	file(WRITE "${VERSION_STRING_DATA}/${file_name}.in" [[// This file was generated by VersionString.cmake
 
 #pragma once
 
 #include <ostream>
 
 constexpr const char k@VAR_PREFIX@ProjectName[] = "@PROJECT_NAME@";
 constexpr const char k@VAR_PREFIX@VersionNumber[] = "@PROJECT_VERSION@";
-constexpr const char k@VAR_PREFIX@RevisionGitTag[] = "@REVISION_GIT_TAGREF@";
 constexpr int k@VAR_PREFIX@BuildNumber = @BUILD_NUMBER@;
+constexpr const char k@VAR_PREFIX@RevisionGitTag[] = "@REVISION_GIT_TAGREF@";
 constexpr const char k@VAR_PREFIX@RevisionDate[] = "@REVISION_DATE_TIME@";
 
 #ifndef VERSION_INFO_DEFINED
 #define VERSION_INFO_DEFINED 1
 
-#define CONCAT(a, b, c)  a_ ## b ## c
-#define CREATE_INSTANCE_NAME(prefix) CONCAT(k, prefix, instance)
-#define CREATE_CLASS_NAME(prefix) CONCAT(version_info_, prefix, impl)
-
 class version_info_base
 {
-	public:
+  public:
 	virtual ~version_info_base() = default;
 
 	static void write(std::ostream &os, bool verbose)
 	{
-		for (auto inst = head(); inst != nullptr; inst = inst->m_next)
-		{
-			os << inst->m_name << " version " << inst->m_version << std::endl;
-
-			if (verbose)
-			{
-				if (inst->m_build != 0)
-				{
-					os << "build: " << inst->m_build << ' ' << inst->m_revision_date << std::endl;
-					if (inst->m_git_tag[0] != 0)
-						os << "git tag: " << inst->m_git_tag << std::endl;
-				}
-				else
-					os << "No revision information available" << std::endl;
-			}
-
-			if (inst->m_next != nullptr)
-				os << std::endl;
-		}
+		auto s_head = head();
+		if (s_head != nullptr)
+			write(s_head, os, verbose);
 	}
 
-	protected:
+  protected:
 
 	struct instance
 	{
 		const char *m_name;
 		const char *m_version;
-		const char *m_git_tag;
 		int m_build;
+		const char *m_git_tag;
 		const char *m_revision_date;
 
 		instance *m_next = nullptr;
 	};
 
+	static void write(const instance *inst, std::ostream &os, bool verbose)
+	{
+		if (inst->m_next != nullptr)
+		{
+			write(inst->m_next, os, verbose);
+			if (not verbose)
+				return;
+			os << '-' << std::endl;
+		}
+
+		os << inst->m_name << " version " << inst->m_version << std::endl;
+
+		if (verbose)
+		{
+			if (inst->m_build != 0)
+			{
+				os << "build: " << inst->m_build << ' ' << inst->m_revision_date << std::endl;
+				if (inst->m_git_tag[0] != 0)
+					os << "git tag: " << inst->m_git_tag << std::endl;
+			}
+			else
+				os << "No revision information available" << std::endl;
+		}
+	}
+
 	using instance_ptr = instance *;
 
 	static instance_ptr &head()
@@ -334,19 +340,18 @@ class version_info_base
 template<typename T>
 class version_info : public version_info_base
 {
-	public:
-
+  public:
 	using implementation_type = T;
 
-	protected:
+  protected:
 	version_info()
 	{
 		auto &s_head = head();
 		static instance s_next{
 			implementation_type::name(),
 			implementation_type::version(),
-			implementation_type::git_tag(),
 			implementation_type::build_number(),
+			implementation_type::git_tag(),
 			implementation_type::revision_date(),
 			s_head };
 		s_head = &s_next;
@@ -360,22 +365,16 @@ inline void write_version_string(std::ostream &os, bool verbose)
 
 #endif
 
-#define INSTANCE_NAME CREATE_INSTANCE_NAME(VAR_PREFIX)
-#define CLASS_NAME CREATE_CLASS_NAME(VAR_PREFIX)
-
-class CLASS_NAME : public version_info<CLASS_NAME>
+class version_info_@IDENT_PREFIX@impl : public version_info<version_info_@IDENT_PREFIX@impl>
 {
-	public:
-
+  public:
 	static constexpr const char *name() { return k@VAR_PREFIX@ProjectName; }
 	static constexpr const char *version() { return k@VAR_PREFIX@VersionNumber; }
-	static constexpr const char *git_tag() { return k@VAR_PREFIX@RevisionGitTag; }
 	static constexpr int build_number() { return k@VAR_PREFIX@BuildNumber; }
+	static constexpr const char *git_tag() { return k@VAR_PREFIX@RevisionGitTag; }
 	static constexpr const char *revision_date() { return k@VAR_PREFIX@RevisionDate; }
-} INSTANCE_NAME;
-
-	
-	]])
+} s_@IDENT_PREFIX@instance;
+]])
 	configure_file("${VERSION_STRING_DATA}/${file_name}.in" "${dir}/${file_name}" @ONLY)
 endfunction()