Generate version info and timestamp at build time

* Print this info from `p21read -v` and in a comment in generated source, not just from `fedex_plus -v`

* Use a function `const char* scl_version()`, instead of using the macro `SCL_COMMIT_ID`

* Fail gracefully if the `.git` directory does not exist (thanks CY!)

* Fixes issue #89

CMakeLists.txt

@@ -48,7 +48,7 @@ ENDIF(COMMAND CMAKE_POLICY)
 PROJECT(SCL)
 
 if( CMAKE_BUILD_TYPE STREQUAL "" )
-  message( "Debug build - to override, rerun cmake with '-DCMAKE_BUILD_TYPE=Release'." )
+  message( "-- Debug build - to override, rerun cmake with '-DCMAKE_BUILD_TYPE=Release'." )
   set( CMAKE_BUILD_TYPE Debug )
 endif()
 
@@ -176,8 +176,8 @@ IF(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
         IF ("${CMAKE_BUILD_TYPE}" MATCHES "Release")
             SET(CMAKE_INSTALL_PREFIX "/usr")
         ELSEIF ("${CMAKE_BUILD_TYPE}" MATCHES "Debug")
-            MESSAGE("setting debug output dir")
             SET(CMAKE_INSTALL_PREFIX "${SCL_SOURCE_DIR}/../scl-install")
+            MESSAGE("---  Setting debug install dir to ${CMAKE_INSTALL_PREFIX}")
         ELSE("${CMAKE_BUILD_TYPE}" MATCHES "Release")
             SET(CMAKE_INSTALL_PREFIX "/usr/local")
         ENDIF ("${CMAKE_BUILD_TYPE}" MATCHES "Release")
@@ -213,23 +213,26 @@ CHECK_FUNCTION_EXISTS(memmove HAVE_MEMMOVE)
 
 CHECK_TYPE_SIZE("ssize_t" SSIZE_T)
 
-#set GIT_COMMIT_ID to the output of `git describe`
-find_package(Git)
-if(GIT_FOUND)
-    execute_process(COMMAND ${GIT_EXECUTABLE} describe --tags RESULT_VARIABLE res_var OUTPUT_VARIABLE GIT_COM_ID )
-    if( NOT ${res_var} EQUAL 0 )
-        set( GIT_COMMIT_ID "unknown (git failed!)")
-        message( WARNING "Git failed (not a repo?). Build will not contain git revision info." )
-    endif()
-    string( REPLACE "\n" "" GIT_COMMIT_ID ${GIT_COM_ID} )
-else()
-    set( GIT_COMMIT_ID "unknown (git not found!)")
-    message( WARNING "Git not found. Build will not contain git revision info." )
-endif()
-
 # Now that all the tests are done, configure the scl_cf.h file:
 configure_file(${SCL_BINARY_DIR}/include/scl_cf.h.in ${SCL_BINARY_DIR}/include/scl_cf.h)
 
+################ create scl_version_string.h, http://stackoverflow.com/questions/3780667
+# Using 'ver_string' instead of 'scl_version_string.h' is a trick to force the
+# command to always execute when the custom target is built. It works because
+# a file by that name never exists.
+add_custom_target(version_string ALL
+                                 DEPENDS ver_string )
+# creates scl_version_string.h using cmake script
+add_custom_command(OUTPUT ver_string ${CMAKE_CURRENT_BINARY_DIR}/include/scl_version_string.h
+                   COMMAND ${CMAKE_COMMAND} -DSOURCE_DIR=${SCL_SOURCE_DIR}
+                                            -DBINARY_DIR=${SCL_BINARY_DIR}
+                                            -P ${SCL_CMAKE_DIR}/scl_version_string.cmake)
+# scl_version_string.h is a generated file
+set_source_files_properties(${CMAKE_CURRENT_BINARY_DIR}/include/scl_version_string.h
+    PROPERTIES GENERATED TRUE
+    HEADER_FILE_ONLY TRUE )
+################
+
 add_definitions( -pedantic -W -Wall -Wundef -Wfloat-equal -Wshadow -Winline -Wno-long-long )
 
 include_directories(

cmake/scl_version_string.cmake

@@ -0,0 +1,59 @@
+#use git for a pretty commit id
+#uses 'git describe --tags', so tags are required in the repo
+#create a tag with 'git tag <name>' and 'git push --tags'
+
+# http://stackoverflow.com/questions/3780667
+# http://www.cmake.org/pipermail/cmake/2009-February/027014.html
+
+#scl_version_string.h defines scl_version() which returns a pretty commit description and a build timestamp.
+if( EXISTS ${SOURCE_DIR}/.git )
+    find_package(Git QUIET)
+    if(GIT_FOUND)
+        execute_process(COMMAND ${GIT_EXECUTABLE} describe --tags RESULT_VARIABLE res_var OUTPUT_VARIABLE GIT_COM_ID )
+        if( NOT ${res_var} EQUAL 0 )
+            set( GIT_COMMIT_ID "unknown (no tags?)")
+            message( WARNING "Git failed (invalid repo, or no tags). Build will not contain git revision info." )
+        endif()
+        string( REPLACE "\n" "" GIT_COMMIT_ID ${GIT_COM_ID} )
+    else(GIT_FOUND)
+        set( GIT_COMMIT_ID "unknown (git not found!)")
+        message( WARNING "Git not found. Build will not contain git revision info." )
+    endif(GIT_FOUND)
+else()
+    set( GIT_COMMIT_ID "unknown (not a repository!)")
+    message( WARNING "Git failed (.git not found). Build will not contain git revision info." )
+endif()
+
+set( res_var 1 )
+IF (WIN32)
+    EXECUTE_PROCESS(COMMAND "date" "/T" RESULT_VARIABLE res_var OUTPUT_VARIABLE TIMESTAMP )
+ELSEIF(UNIX)
+    EXECUTE_PROCESS(COMMAND "date" RESULT_VARIABLE res_var OUTPUT_VARIABLE TIMESTAMP )
+ELSE()
+    MESSAGE(WARNING "Unknown platform: date not included in version string")
+ENDIF()
+if( NOT ${res_var} EQUAL 0 )
+    SET( TIMESTAMP "000000" )
+else()
+    string( REPLACE "\n" "" TIMESTAMP ${TIMESTAMP} )
+endif()
+
+set( vstring "//scl_version_string.h - written by cmake. Changes will be lost!\n"
+             "#ifndef SCL_VERSION_STRING\n"
+             "#define SCL_VERSION_STRING\n\n"
+             "/*\n** Returns a string like \"test-1-g5e1fb47, built on <timestamp>\", where test is the\n"
+             "** name of the last tagged git revision, 1 is the number of commits since that tag,\n"
+             "** 'g' is unknown, 5e1fb47 is the first 7 chars of the git sha1 commit id, and\n"
+             "** <timestamp> is the output of your system's 'date' command.\n*/\n\n"
+             "const char* scl_version() {\n"
+             "    return \"git commit id ${GIT_COMMIT_ID}, built on ${TIMESTAMP}\"\;\n"
+             "}\n\n"
+             "#endif\n"
+   )
+
+file(WRITE scl_version_string.h.txt ${vstring} )
+# copy the file to the final header only if the version changes
+# reduces needless rebuilds
+execute_process(COMMAND ${CMAKE_COMMAND} -E copy_if_different
+                        scl_version_string.h.txt ${BINARY_DIR}/include/scl_version_string.h)
+message("-- scl_version_string.h is up-to-date.")

data/CMakeLists.txt

@@ -86,6 +86,7 @@ FUNCTION(BUILD_A_SCHEMA SCHEMA_FILE)
     set_tests_properties( build_cpp_${PROJECT_NAME} PROPERTIES DEPENDS generate_cpp_${SCHEMA_SHORT_NAME} LABELS cpp_schema_build )
 
     add_executable( p21read_${PROJECT_NAME} ${SCL_SOURCE_DIR}/src/test/p21read/p21read.cc )
+    add_dependencies( p21read_${PROJECT_NAME} version_string )
     target_link_libraries( p21read_${PROJECT_NAME} ${PROJECT_NAME} )
     set_target_properties( p21read_${PROJECT_NAME} PROPERTIES COMPILE_FLAGS
                            ${${PROJECT_NAME}_COMPILE_FLAGS} )

include/scl_cf_cmake.h.in

@@ -9,5 +9,3 @@
 #cmakedefine HAVE_MEMMOVE 1
 #cmakedefine HAVE_SSIZE_T 1
 
-//cmake updates this at build time
-#define SCL_COMMIT_ID "@GIT_COMMIT_ID@"

src/express/fedex.c

@@ -72,6 +72,7 @@
  */
 
 #include "scl_cf.h"
+#include "scl_version_string.h"
 #include <stdlib.h>
 #include <stdio.h>
 #include <unistd.h>
@@ -91,7 +92,7 @@ char EXPRESSgetopt_options[256] = "Bbd:e:i:w:p:u:l:nrvz";
 int no_need_to_work = 0; /* TRUE if we can exit gracefully without doing any work */
 
 void print_fedex_version( void ) {
-    printf( "%s\nSCL version id (from git): %s\nhttp://github.com/mpictor/StepClassLibrary\n", EXPRESSprogram_name, SCL_COMMIT_ID );
+    fprintf( stderr, "Build info for %s: %s\nhttp://github.com/mpictor/StepClassLibrary\n", EXPRESSprogram_name, scl_version() );
     no_need_to_work = 1;
 }
 

src/fedex_plus/CMakeLists.txt

@@ -33,3 +33,4 @@ ENDIF()
 
 SCL_ADDEXEC(fedex_plus "${fedex_plus_SOURCES}" "libexppp express")
 
+add_dependencies( fedex_plus version_string )

src/fedex_plus/classes_misc.c

@@ -18,6 +18,8 @@ for the STEP Standard Data Access Interface as defined in document
 N350 ( August 31, 1993 ) of ISO 10303 TC184/SC4/WG7.
 *******************************************************************/
 
+extern char* scl_version();
+
 extern int multiple_inheritance;
 /*extern int corba_binding; */
 
@@ -125,9 +127,9 @@ FILEcreate( const char * filename ) {
     }
 
     fprintf( file, "#ifndef  %s\n", fn = StrToConstant( filename ) );
-    fprintf( file, "#define  %s\n", fn );
+    fprintf( file, "#define  %s\n\n", fn );
 
-    fprintf( file, "// This file was generated by fedex_plus %s.\n", scl_version() );
+    fprintf( file, "// This file was generated by fedex_plus,\n// %s.\n", scl_version() );
     fprintf( file, "// You probably don't want to edit it since your modifications\n" );
     fprintf( file, "// will be lost if fedex_plus is used to regenerate it.\n" );
     return ( file );

src/test/p21read/p21read.cc

@@ -13,6 +13,7 @@
 */
 
 extern void SchemaInit( class Registry & );
+#include "scl_version_string.h"
 #include <STEPfile.h>
 #include <sdai.h>
 #include <STEPattribute.h>
@@ -82,12 +83,18 @@ void checkSchemaName( Registry & reg, STEPfile & sf, bool ignoreErr ) {
     }
 }
 
+void printVersion(const char * exe) {
+    std::cout << exe << " build info: " << scl_version() << std::endl;
+}
+
 void printUse(const char * exe) {
     std::cout << "p21read - read a STEP Part 21 exchange file using SCL, and write the data to another file." << std::endl;
     std::cout << "Syntax:  " << exe << " [-i] [-s] infile [outfile]" << std::endl;
     std::cout << "Use '-i' to ignore a schema name mismatch." << std::endl;
     std::cout << "Use '-s' for strict interpretation (attributes that are \"missing and required\" will cause errors)." << std::endl;
+    std::cout << "Use '-v' to print the version info below and exit." << std::endl;
     std::cout << "Use '--' as the last argument if a file name starts with a dash." << std::endl;
+    printVersion(exe);
     exit( 1 );
 }
 
@@ -98,7 +105,7 @@ int main( int argc, char * argv[] ) {
     if( argc > 4 || argc < 2 ) {
         printUse(argv[0]);
     }
-    while( ( c = getopt( argc, argv, "is" ) ) != -1 ) {
+    while( ( c = getopt( argc, argv, "isv" ) ) != -1 ) {
         switch( c ) {
             case 'i':
                 ignoreErr = true;
@@ -106,6 +113,9 @@ int main( int argc, char * argv[] ) {
             case 's':
                 strict = true;
                 break;
+            case 'v':
+                printVersion(argv[0]);
+                exit(0);
             case '?':
             default:
                 printUse(argv[0]);
@@ -113,16 +123,14 @@ int main( int argc, char * argv[] ) {
     }
 
 
-///////////////////////////////////////////////////////////////////////////////
+    ///////////////////////////////////////////////////////////////////////////////
-// You have to initialize the schema before you do anything else.
+    // You have to initialize the schema before you do anything else.
-// This initializes all of the registry information for the schema you
+    // This initializes all of the registry information for the schema you
-// plan to use.  The SchemaInit() function is generated by fedex_plus.
+    // plan to use.  The SchemaInit() function is generated by fedex_plus.
-// See the 'extern' stmt above.
+    // See the 'extern' stmt above.
-//
+    //
-// The registry is always going to be in memory.
+    // The registry is always going to be in memory.
-//
+    ///////////////////////////////////////////////////////////////////////////////
-///////////////////////////////////////////////////////////////////////////////
-
     Registry  registry( SchemaInit );
     InstMgr   instance_list;
     STEPfile  sfile( registry, instance_list, "", strict );