** ** Source tree organization ** ****************************************************** There is at least 5 sub-projects in the tree: - XBT: eXtended Bundle of Tools (low-level toolbox: logging, datatypes). - SURF: a SimUlation aRtiFact. This is the simulation kernel. - MSG: originally MetaSimGrid, MSG is a simple distributed application simulator. - GRAS: Grid Reality And Simulation (message passing API with two implementations allowing to compile programs on top of the simulator or for the real life without code modification) - AMOK: Advanced Metacomputing Overlay Kit (high level toolbox; Grid application elements such as distributed database, topology discovery service, and so on) They are all in the same tree because they are complementary tools and having all of them in the same package makes the installation easier for end-users. Moreover, it enables to share the compilation chain and eases the development. The tree is not splited on projects, but on file finality: include/ -> all *public* headers include/xbt/*.h -> one file per module include/gras.h -> file including all modules headers (same for xbt instead of gras) src/Makefile.am -> main makefile. All projects should fit in only one library (I mean 2, RL+SG), which is compiled here. Since all object.o files are placed here, you should choose the name of c files carfully to avoid conflict. src/gras/DataDesc -> typical project module src/gras/DataDesc/datadesc_interface.h -> visible to any GRAS modules; masked to the user and GROS/AMOK/SURF src/gras/DataDesc/datadesc_private.h -> visible only from this module So, the modules have 3 levels of publicity for their interface. Private, internal to GRAS, public. Of course, I try to keep as much stuff private as possible. src/include -> another location for protected headers. Used by SURF, and other should be converted, since this is the Right Thing. testsuite/ -> The more test the better. Same organization than src/ and include/ Tests are allowed to load some headers of the module they test. All tests should be listed in run_test.in so that they get run on 'make check'. They are not listed directly in the check_PROGRAMS part of the makefile because run_test knows about the gras logging features and relaunch with full details the failed tests. examples/ -> Supposed to be copy/pastable by the user, so keep it clear and avoid any kind of trick. In particular, do only include the public headers here. ** ** Indentation standard ** ***************************************************** Most files use the Kernighan & Ritchie coding style with 2 spaces of indentation. The indent program can help you to stick to it: indent -br -brs -ce -bbo -bad -bap --dont-break-procedure-type --no-tabs --cuddle-do-while --cuddle-else --indent-level2 --leave-preprocessor-space --no-space-after-function-call-names FIXME: this list of arguments is still to be discussed, maybe ** ** Type naming standard ** ***************************************************** It may sound strange, but the type naming convention was source of intense discution between da GRAS posse members. The convention we came to may not be the best solution, but it has the merit to exist and leave everyone work. So please stick to it. - ???_t is a valid type (builded with typedef) - s_toto_t is a structure (access to fields with .) - s_toto is a structure needing 'struct' keyword to be used - e_toto_t is an enum - u_toto_t is an union - u_toto is an union needing 'union' keyword to be used - toto_t is an 'object' (struct*) Please to not call toto_t something else than an 'object' (ie, something you have to call _new and _free on it). Exemple: typedef struct s_toto {} s_toto_t, *toto_t; typedef enum {} e_toto_t; Moreover, only toto_t (and e_toto_t) are public. The rest (mainly s_toto_t) is private. If you see any part of the code not following this convention, this is a bug. Please report it (or fix it yourself if you can). ** ** Random bits about coding standards and portability ** ***************************************************** MALLOC: Don't use it, or you'll have to check the result (and do some dirty stuff on AIX). Use xbt_malloc (or even better, xbt_new) instead. SIZE_T If possible, avoid size_t and use unsigned long instead. If not, #include in all files manipulating size_t do cast it to unsigned long before printing (and use %lu) PRINTF pointer difference printf ("diff = %ld\n", (long) (pointer2 - pointer1)); ** ** Commenting the source: doxygen ** **************************************************** The global structure of the documentation is in doc/modules.doc The structure of each module (xbt, gras, etc) is in doc/module-.doc The structure of a module is in its public header. This way, you're sure to see all the public interface (and only it). The different parts of the interface are grouped using the @name construct, even if it's buggy. Since parts often get reordered, it's better to add numbers to the parts (so that users can see the intended order). The documentation of each type and macro are also in the public header since this is were they live. The documentation of each function must be in the C file were it lives. Any public element (function, type and macro) must have a @brief part. ** ** XBT virtualization mecanism ** **************************************************** There is some functionnalities that we want to virtualize in XBT. We want xbt_time to give the simulated clock when running on top of the simulator, and the host clock when running on a real system. This could be placed in GRAS (and was, historically), but there is some reason to lower it down to XBT. Here is the used naming scheme: - xbt__(): functions working both in SG and RL - xbt_os__(): RL functions usable even in simulator That way, in libsimgrid, we still can use native functions if we want to. It may for example be useful to get the real time when implementing the simulator. Think of the SIGINT handler, which wants to see if the user pressed the key twice in a 5 seconds interval. This is of little use to check the simulated time here. Here is the file layout: - xbt_rl_.c: native implementation (xbt__()). Simply call the corresponding xbt_os__. Part only of libgras.so - xbt_sg_.c: SIMIX implementation xbt__()). Simply call the corresponding SIMIX implementation. Part only of libsimgrid.so - xbt_os_.c: body of the functions implementing natively the stuff (xbt_os__()). Part of both libgras.so and libsimgrid.so Since there is almost nothing in xbt_rl_module.c and xbt_sg_module.c, it'd be better to use symbol aliasing here (to declare in the object code that the same function have two names), but I'm still investigating the portability of the thing to windows.