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[fU-cvs] libfunutil/lib/s11n DLLLoader.cpp,1.1,1.2 DLLLoader.h,1.1,1.2 Makefile,1.1,1.2 S11n.h,1.1,1.2
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From: <sg...@us...> - 2003-09-28 01:35:52
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Update of /cvsroot/libfunutil/libfunutil/lib/s11n
In directory sc8-pr-cvs1:/tmp/cvs-serv3118/lib/s11n
Modified Files:
DLLLoader.cpp DLLLoader.h Makefile S11n.h
Log Message:
refinements/improvments to the classloader. Added DLLLoader_boostrap "callback" support, to run boostrapping code when opening an DLL. This allows a way around using S11N_INSTANTIATOR, and a way to dynamically add factories to the classloader from DLLs.
Index: DLLLoader.cpp
===================================================================
RCS file: /cvsroot/libfunutil/libfunutil/lib/s11n/DLLLoader.cpp,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -d -r1.1 -r1.2
--- DLLLoader.cpp 27 Sep 2003 22:36:54 -0000 1.1
+++ DLLLoader.cpp 28 Sep 2003 01:35:30 -0000 1.2
@@ -8,15 +8,54 @@
#include "DLLLoader.h"
#include <s11n/s11n-macros.h> // COUT/CERR
+
+// note: if you define DLLLOADER_DEFAULT_PATH via the command line, be sure to
+// escape the quote marks. e.g.:
+// DLLLoader_cpp_CPPFLAGS = -DDLLLOADER_DEFAULT_PATH=\".:$(prefix)/lib\"
+#ifndef DLLLOADER_DEFAULT_PATH
+# define DLLLOADER_DEFAULT_PATH "."
+#endif
+
+#define DLLLOADER_PATH DLLLOADER_DEFAULT_PATH
+
namespace s11n
{
static void * soh_main = NULL;
- unsigned long DLLLoader::inst_count = 0;
+ unsigned long DLLLoader_inst_count = 0;
+
+ /**
+ Looks for a bootstrap function in newly-opened shared
+ objects, and runs it if it exists. Returns true if the
+ object has a registry, else false. It only runs the
+ registry the first time it is passed a given pointer.
+ */
+ bool check_for_registry( void * soh )
+ {
+ if( ! soh ) return false;
+ const char * funcname = "DLLLoader_bootstrap";
+ typedef void (*registry)();
+ typedef std::map<void *,unsigned long int> done_map;
+ static done_map done;
+ if( done[soh] ) return true;
+ //COUT << "check_for_registry(" << std::hex << soh << ")"<<std::endl;
+ done[soh] = 1;
+ registry reg;
+ reg = (registry) dlsym( soh, funcname );
+ if( ! reg )
+ {
+ //CERR << "no " << funcname << "() found in " << std::hex << soh << "" << std::endl;
+ return false;
+ }
+ reg();
+ return true;
+ }
+
+
DLLLoader::DLLLoader()
{
- ++inst_count;
+ ++DLLLoader_inst_count;
this->path().addExtension( ".so" );
- this->path().addPath( "." );
+ this->path().setPath( DLLLOADER_PATH );
const char * p = getenv( "S11N_PATH" );
if( ! p ) getenv( "LD_LIBRARY_PATH" );
if( p )
@@ -25,15 +64,15 @@
}
if( ! soh_main )
{
- soh_main = dlopen( 0, RTLD_NOW | RTLD_GLOBAL );
- //COUT << "Address of main app, from dlopen() perspective: " << std::hex << soh_main<<""<<std::endl;
+ soh_main = dlopen( NULL, RTLD_NOW | RTLD_GLOBAL );
+ check_for_registry( soh_main );
}
}
DLLLoader::~DLLLoader()
{
- if( 0 == --inst_count )
+ if( 0 == --DLLLoader_inst_count )
{
dlclose( soh_main );
DLLLoader::soh_map_type & map = DLLLoader::soh_map();
@@ -41,7 +80,7 @@
DLLLoader::soh_map_type::iterator et = map.end();
for( ; it != et; ++it )
{
- COUT << "Closing DLL: " << std::hex <<(*it).second<<std::endl;
+ //COUT << "Closing DLL: " << std::hex <<(*it).second<<std::endl;
dlclose( (*it).second );
}
}
@@ -60,77 +99,106 @@
static DLLLoader::symbol_map_type bob; return bob;
}
+
+
DLLLoader::value_type * DLLLoader::load( const std::string & key ) const
{
//COUT << "load("<<key<<")"<<std::endl;
- //static void * error_entry = NULL; // maintenance note: this might Cause Grief with subclasses.
- // mostly untested.
- // todo: add an option to force-deserialize a node, even when the types don't match.
typedef ThisType::value_type CHT;
- CHT *ch = this->ParentClass::load( key );
+ CHT *ch = NULL;
+ ch = this->ParentClass::load( key );
if ( ch ) return ch;
- std::string xlated = key;
- std::string::size_type colon = xlated.rfind( ":" );
- if( std::string::npos != colon )
+
+ void * soh = 0;
+ std::string xlated = key; // key, translated to remove namespace part (because :: is not filesystem-friendly).
+ std::string path = key;
+ DLLLoader::soh_map_type & map = DLLLoader::soh_map();
+ DLLLoader::soh_map_type::iterator it = map.find(key);
+ if( map.end() != it )
{
- xlated = key.substr( colon + 1 );
+ soh = (*it).second;
+ if( NULL == soh ) return NULL;
}
- string path = this->path().find( xlated );
- if ( path.empty() )
+ else
{
- CERR << "Neither in-built class nor DLL found for "<<key<<" ["<<xlated<<"]"<<std::endl;
- return NULL;
+ std::string::size_type colon = xlated.rfind( ":" );
+ if( std::string::npos != colon )
+ {
+ xlated = key.substr( colon + 1 );
+ }
+ path = this->path().find( xlated );
+ if ( path.empty() )
+ {
+ CERR << "Neither in-built class nor DLL found for "<<key<<" ["<<xlated<<"]. path=["<<this->path()<<"]"<<std::endl;
+ return NULL;
+ }
+ it = map.find(path);
+ //COUT << "load("<<key<<" ["<<xlated<<"]) dll path="<<path<<std::endl;
}
- //COUT << "load("<<key<<" ["<<xlated<<"]) dll path="<<path<<std::endl;
- void * soh = 0;
-
- DLLLoader::soh_map_type & map = DLLLoader::soh_map();
- DLLLoader::soh_map_type::iterator it = map.find(key);
if( map.end() != it )
{
soh = (*it).second;
- //COUT << "cached entry ["<<key<<"]: " << std::hex << soh << std::endl;
+ //COUT << "cached entry ["<<path<<"]: " << std::hex << soh << std::endl;
if( NULL == soh ) return NULL;
}
else
{
soh = dlopen( path.c_str(), RTLD_NOW | RTLD_GLOBAL );
- if( ! soh ) soh = soh_main;
+ if( ! soh )
+ {
+ COUT << "error? dlerror() says: " << dlerror() << std::endl;
+ soh = soh_main;
+ }
+ //COUT << "key="<<key<<" ["<<xlated<<"], path=["<<path<<"], soh = " << std::hex << soh << ", dll path="<<path<<std::endl;
if( ! soh )
{
- map[key] = (void *)NULL;
+ map[path] = map[key] = (void *)NULL;
return NULL;
}
- map[key] = soh;
+ map[path] = map[key] = soh;
+ }
+
+ if( check_for_registry( soh ) )
+ { // give parent another chance. registration may have assigned a factory.
+ ch = this->ParentClass::load( key );
+ if( ch ) return ch;
}
- //COUT << "soh = " << std::hex << soh << std::endl;
- const char * inst_funcname = "instantiateSerializable";
- DLLLoader::instantiator_func instantiator;
+
+ DLLLoader::instantiator_func instantiator = 0;
DLLLoader::symbol_map_type & symmap = DLLLoader::symbol_map();
DLLLoader::symbol_map_type::iterator sit = symmap.find(soh);
- if( symmap.end() == sit )
+ if( symmap.end() != sit )
{
- if( (instantiator = (instantiator_func) dlsym( soh, inst_funcname )) )
- {
- symmap[soh] = instantiator;
- }
-
- //COUT << "instantiator = " << std::hex << instantiator << std::endl;
+ instantiator = (*sit).second;
}
else
{
- instantiator = (*sit).second;
+ //const char * inst_funcname = "instantiateSerializable";
+ std::string inst_funcname = "new_" + xlated;
+ if( (instantiator = (instantiator_func) dlsym( soh, inst_funcname.c_str() )) )
+ {
+ symmap[soh] = instantiator;
+ }
+ else
+ {
+ symmap[soh] = NULL;
+ }
}
+
if( ! instantiator )
{
- CERR << "error? dlerror() says: " <<dlerror() << std::endl;
+ //CERR << "error? dlerror() says: " <<dlerror() << std::endl;
if( soh && (soh_main != soh) ) dlclose( soh );
- map[key] = (void *)NULL;
+ map[path] = map[key] = (void *)NULL;
return NULL;
}
- ch = instantiator( key.c_str() );
+
+ if( NULL != instantiator )
+ {
+ ch = instantiator( key.c_str() );
+ }
return ch;
}
Index: DLLLoader.h
===================================================================
RCS file: /cvsroot/libfunutil/libfunutil/lib/s11n/DLLLoader.h,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -d -r1.1 -r1.2
--- DLLLoader.h 27 Sep 2003 22:36:54 -0000 1.1
+++ DLLLoader.h 28 Sep 2003 01:35:30 -0000 1.2
@@ -39,12 +39,38 @@
This class represents my very first usage of dlopen(), and there
may be bugs related to my use of dlopen()/dlclose().
+
+
+
+ Instead of using the S11N_INSTANTIATOR macro you may do the
+ following:
+
+ Define an extern "C" function with this sigature:
+
+ void DLLLoader_bootstrap();
+
+ If that function exists it is called when the class is loaded.
+ This gives the class a chance to register factories for other
+ names of itself or for dependent classes.
+
+ Example:
+
+ extern "C" {
+ void DLLLoader_bootstrap()
+ {
+ s11n::register_serializable_type<foo::FooClass>("FooClass");
+ s11n::register_serializable_type<foo::FooClass>("foo::FooClass");
+ s11n::register_serializable_type<foo::FooClass>("WonderBra");
+ }
+ }
+
+ This approach prohibits more than one definition in the same DLL.
+
*/
- class DLLLoader : public s11n::ClassLoader < s11n::Serializable >
+ class DLLLoader : public s11n::ClassLoader < s11n::Serializable, std::string >
{
private:
- typedef s11n::ClassLoader < s11n::Serializable > ParentClass;
- static unsigned long inst_count;
+ typedef s11n::ClassLoader < s11n::Serializable, std::string > ParentClass;
protected:
typedef s11n::Serializable * (*instantiator_func)( const char * );
typedef std::map<std::string,void *> soh_map_type;
Index: Makefile
===================================================================
RCS file: /cvsroot/libfunutil/libfunutil/lib/s11n/Makefile,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -d -r1.1 -r1.2
--- Makefile 27 Sep 2003 22:36:54 -0000 1.1
+++ Makefile 28 Sep 2003 01:35:30 -0000 1.2
@@ -38,10 +38,13 @@
endif
+top_srcdir_absolute = $(shell cd $(top_srcdir) && pwd)
+DLLLoader_cpp_CPPFLAGS = -DDLLLOADER_DEFAULT_PATH=\".:$(top_srcdir_absolute)/lib/s11n:$(prefix)/lib\"
OBJECTS = $(patsubst %.cpp,%.o,$(SOURCES))
PARSER_OBJECTS = $(addprefix parsers/,flex_lexers.o funtxt.flex.o funxml.flex.o select_lexer.flex.o simplexml.flex.o)
+INSTALL_PACKAGE_HEADERS_DEST = $(prefix)/include/s11n
INSTALL_PACKAGE_HEADERS = $(HEADERS)
STATIC_LIBS = libs11n
@@ -52,10 +55,7 @@
ifeq (1,$(build_s11n_so))
SHARED_LIBS = $(STATIC_LIBS)
libs11n_so_OBJECTS = $(libs11n_a_OBJECTS)
-libs11n_so_VERSION = 0.1.0
-ifeq (1,$(configure_with_libreadline))
-libs11n_so_LDADD += $(LIBREADLINE_LDADD)
-endif
+libs11n_so_VERSION = 0.0.1
include $(toc_makesdir)/cpp_dynamic_libs.make
endif
# ^^^^ build shared libs?
Index: S11n.h
===================================================================
RCS file: /cvsroot/libfunutil/libfunutil/lib/s11n/S11n.h,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -d -r1.1 -r1.2
--- S11n.h 27 Sep 2003 22:36:54 -0000 1.1
+++ S11n.h 28 Sep 2003 01:35:30 -0000 1.2
@@ -27,19 +27,31 @@
Alternately, they should have an extern "C" function with this signature:
- YourClass * instantiateSerializable( const char * );
+ YourClass * new_YourClass( const char * );
- The char * parameter does nothing in the default implementation, but
- could be implemented to provide (e.g.) multiple key-to-class mappings,
- or access to multiple loadable classes in the same object file.
+ The char * parameter does nothing in the default implementation,
+ but could be implemented to provide (e.g.) multiple key-to-class
+ mappings, or access to multiple loadable classes in the same object
+ file, or perhaps to use for proxy loading.
+
+ YourClass must currently be a Serializable type.
+
+ Sample usages:
+
+ S11N_INSTANTIATOR(,GlobalNameSpaceClass);
+ S11N_INSTANTIATOR(my::namespace,SomeClass);
+
+ i appologize about the weird arguments syntax, but it's the best i can
+ manage with C macros.
*/
-#define S11N_INSTANTIATOR(ClsName) extern "C" {\
- ClsName * instantiateSerializable( const char * clname ) \
+#define S11N_INSTANTIATOR(NS,ClsName) \
+ extern "C" {\
+ NS::ClsName * new_ ## ClsName( const char * clname ) \
{ \
- /** COUT << # ClsName << " * instantiateSerializable("<<clname<<")"<<std::endl;*/ \
- return new ClsName; }\
- };
+ /**COUT << # ClsName << " * instantiateSerializable("<<clname<<")"<<std::endl;*/ \
+ return new NS::ClsName; \
+ }};
namespace s11n
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