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diff --git a/docs/docbook/devdoc/modules.sgml b/docs/docbook/devdoc/modules.sgml deleted file mode 100644 index 0bcdadc66c..0000000000 --- a/docs/docbook/devdoc/modules.sgml +++ /dev/null @@ -1,156 +0,0 @@ -<chapter id="modules"> -<chapterinfo> - <author> - <firstname>Jelmer</firstname><surname>Vernooij</surname> - <affiliation> - <orgname>Samba Team</orgname> - <address><email>jelmer@samba.org</email></address> - </affiliation> - </author> - <pubdate> 19 March 2003 </pubdate> -</chapterinfo> - -<title>Modules</title> - -<sect1> -<title>Advantages</title> - -<para> -The new modules system has the following advantages: -</para> - -<simplelist> -<member>Transparent loading of static and shared modules (no need -for a subsystem to know about modules)</member> -<member>Simple selection between shared and static modules at configure time</member> -<member>"preload modules" option for increasing performance for stable modules</member> -<member>No nasty #define stuff anymore</member> -<member>All backends are available as plugin now (including pdb_ldap and pdb_tdb)</member> -</simplelist> -</sect1> - -<sect1> -<title>Loading modules</title> - -<para> -Some subsystems in samba use different backends. These backends can be -either statically linked in to samba or available as a plugin. A subsystem -should have a function that allows a module to register itself. For example, -the passdb subsystem has: -</para> - -<para><programlisting> -BOOL smb_register_passdb(const char *name, pdb_init_function init, int version); -</programlisting></para> - -<para> -This function will be called by the initialisation function of the module to -register itself. -</para> - -<sect2> -<title>Static modules</title> - -<para> -The modules system compiles a list of initialisation functions for the -static modules of each subsystem. This is a define. For example, -it is here currently (from <filename>include/config.h</filename>): -</para> - -<para><programlisting> -/* Static init functions */ -#define static_init_pdb { pdb_mysql_init(); pdb_ldap_init(); pdb_smbpasswd_init(); pdb_tdbsam_init(); pdb_guest_init();} -</programlisting></para> - -<para> -These functions should be called before the subsystem is used. That -should be done when the subsystem is initialised or first used. -</para> - -</sect2> - -<sect2> -<title>Shared modules</title> - -<para> -If a subsystem needs a certain backend, it should check if it has -already been registered. If the backend hasn't been registered already, -the subsystem should call smb_probe_module(char *subsystem, char *backend). -This function tries to load the correct module from a certain path -($LIBDIR/subsystem/backend.so). If the first character in 'backend' -is a slash, smb_probe_module() tries to load the module from the -absolute path specified in 'backend'. -</para> - -<para>After smb_probe_module() has been executed, the subsystem -should check again if the module has been registered. -</para> - -</sect2> -</sect1> - -<sect1> -<title>Writing modules</title> - -<para> -Each module has an initialisation function. For modules that are -included with samba this name is '<replaceable>subsystem</replaceable>_<replaceable>backend</replaceable>_init'. For external modules (that will never be built-in, but only available as a module) this name is always 'init_module'. (In the case of modules included with samba, the configure system will add a #define subsystem_backend_init() init_module()). -The prototype for these functions is: -</para> - -<para><programlisting> -int init_module(void); -</programlisting></para> - -<para>This function should call one or more -registration functions. The function should return non-zero on success and zero on -failure.</para> - -<para>For example, pdb_ldap_init() contains: </para> - -<para><programlisting> -int pdb_ldap_init(void) -{ - smb_register_passdb("ldapsam", pdb_init_ldapsam, PASSDB_INTERFACE_VERSION); - smb_register_passdb("ldapsam_nua", pdb_init_ldapsam_nua, PASSDB_INTERFACE_VERSION); - return TRUE; -} -</programlisting></para> - -<sect2> -<title>Static/Shared selection in configure.in</title> - -<para> -Some macros in configure.in generate the various defines and substs that -are necessary for the system to work correct. All modules that should -be built by default have to be added to the variable 'default_modules'. -For example, if ldap is found, pdb_ldap is added to this variable. -</para> - -<para> -On the bottom of configure.in, SMB_MODULE() should be called -for each module and SMB_SUBSYSTEM() for each subsystem. -</para> - -<para>Syntax:</para> - -<para><programlisting> -SMB_MODULE(<replaceable>subsystem</replaceable>_<replaceable>backend</replaceable>, <replaceable>object files</replaceable>, <replaceable>plugin name</replaceable>, <replaceable>subsystem name</replaceable>, <replaceable>static_action</replaceable>, <replaceable>shared_action</replaceable>) -SMB_SUBSYSTEM(<replaceable>subsystem</replaceable>) -</programlisting></para> - -<para>Also, make sure to add the correct directives to -<filename>Makefile.in</filename>. <replaceable>@SUBSYSTEM_STATIC@</replaceable> -will be replaced with a list of objects files of the modules that need to -be linked in statically. <replaceable>@SUBSYSTEM_MODULES@</replaceable> will -be replaced with the names of the plugins to build. -</para> - -<para>You must make sure all .c files that contain defines that can -be changed by ./configure are rebuilded in the 'modules_clean' make target. -Practically, this means all c files that contain <command>static_init_subsystem;</command> calls need to be rebuilded. -</para> - -</sect2> -</sect1> -</chapter> |