**
******************************************************
-There is 4 projects in the tree:
-
- - GROS: no fancy name yet (low-level toolbox: logging, datatypes).
- - 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)
- - SURF: Server for the Use of Resource Fictions (the simulator used
- in GRAS and more)
- - 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 GRAS depends on SURF which depends on
-GRAS (that's the only cycle here, we're not *that* vicious).
-
-The tree is not splited on projects, but on file finality:
+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.
+ - SMPI: Simulated MPI, to run MPI application using emulation technics;
+ - MC: model-checker;
+ - SIMIX: basix interface for simulated processes. This layer defines simcalls
+ (simulation calls) exposed to the simulated processes by the SIMIX "kernel".
+ This interface is used to implement the MSG, SMPI layers.
+ - SIMDAG;
+
+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 split on projects, but on file finality:
include/ -> all *public* headers
- include/gros/*.h -> one file per module
- include/gros.h -> file including all modules headers
- (same for gras, surf and amok instead of gros)
-
- 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.
-
- 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.
-
+ include/xbt/*.h -> one file per module
+
+ src/include -> another location for protected headers. Used by SURF, and
+ other should be converted, since this is the Right Thing.
+
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.
-
+
+ teshsuite/ -> The more test the better. Put in there any strange test
+ doing things that the users are not supposed to do,
+ just to see if our framework is robust to incorrect and
+ unusual behaviors. All tests written in this section
+ should leverage our tesh(1) utility.
+
+**
+** 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 -kr -l120 -nut -i2 -lps -npcs -br -brs -ce -cdw -bbo -npsl <myfile>
+
+The script ./tools/internal/indent runs indent with the appropriate options.
+
+If you use Eclipse, please import the settings in ./tools/internal/eclipse-formating.xml
+
+**
+** Type naming standard
+**
+*****************************************************
+
+It may sound strange, but the type naming convention was source of intense
+discussion between da SimGrid 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 (built 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).
+
+Example:
+ 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:
- You must cast the result of malloc on AIX.
- It's even better to use gras_new when possible.
+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
+SIZE_T (FIXME: obsolete?)
If possible, avoid size_t and use unsigned long instead. If not,
-
#include <sys/types.h> in all files manipulating size_t
- do cast it to unsigned long before printing (and use %lu)
-
-PRINTF pointer difference
+ do cast it to unsigned long before printing (and use %lu),
+ or use %zu.
+
+INTEGERS
+ Please avoid to use long ints. This is the source of many compatibility
+ problems between 32 bits and 64 bits archs. Either use plain ints (generally
+ 32 bits wide) or long long ints (64 bits wide, at least). At last resort
+ consider using integer types defined in C99 by <stdint.h>.
+
+PRINTF pointer difference (FIXME: advertise %td instead?)
printf ("diff = %ld\n", (long) (pointer2 - pointer1));
-
-
+INLINE functions
+ The definition of a inline function must be visible when it is used.
+ As such, an inline function should be defined (an not only declared)
+ in header file (.h) with attributes 'static XBT_INLINE'. It should
+ not be defined in source file (.c).
+
+**
+** Commenting the source: doxygen
+**
+****************************************************
+
+The global structure of the documentation is in doc/modules.doc
+
+The structure of each module (xbt, msg, etc) is in doc/module-<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 mechanism (FIXME: this section is deprecated)
+**
+****************************************************
+
+There is some functionalities 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_<module>_<func>(): functions working both in SG and RL
+ - xbt_os_<module>_<func>(): 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_<module>.c: native implementation (xbt_<module>_<func>()).
+ Simply call the corresponding xbt_os_<module>_<func>.
+ Part only of libgras.so
+
+ - xbt_sg_<module>.c: SIMIX implementation xbt_<module>_<func>()).
+ Simply call the corresponding SIMIX implementation.
+ Part only of libsimgrid.so
+
+ - xbt_os_<module>.c: body of the functions implementing natively the
+ stuff (xbt_os_<module>_<func>()).
+ 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.
+
+
+*
+* SimGrid Hacker Survival Guide (FIXME: should be betterly placed)
+********************************
+
+* Before pushing any change, don't forget to check if the compilation
+ passes with compiler optimizations and warnings turned on:
+ cmake -Denable_compile_optimizations=ON \
+ -Denable_compile_warnings=ON
+
+* Your commit message should follow the git habits, explained eg here:
+ http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html
+
+* When you add/remove files, and/or make changes in the lists of files to build,
+ please check that "make distcheck" still succeeds. This is needed to ensure
+ that the generated archive is consistent.
+
+* If you want to debug memory allocation problems, here are a few hints:
+ - disable compiler optimizations, to have better backtraces;
+ - disable the mallocators, or it will be hard to match malloc's with
+ free's;
+ - disable model checking, unless your problem lies in the model
+ checker part of SimGrid (MC brings its own malloc implementation,
+ which valgrind doesn't understand).
+ All this is configured with:
+ cmake -Denable_model-checking=OFF \
+ -Denable_mallocators=OFF \
+ -Denable_compile_optimizations=OFF
+
+* If you break the logs (for example while hacking in the dynars), you
+ want to define XBT_LOG_MAYDAY at the beginning of log.h. It will
+ deactivate the whole logging mechanism, switching to printfs
+ instead. SimGrid becomes incredibly verbose when doing so, but it
+ you let you fixing the dynars.
