On MC mode, return immediately after handling the wait request.

[simgrid.git] / README.coding

diff --git a/README.coding b/README.coding
index 0460634..2a8302a 100644 (file)
--- a/README.coding
+++ b/README.coding
@@ -3,26 +3,29 @@
 **
 ******************************************************
 
 **
 ******************************************************
 

-There is 4 projects in the tree:
+There is at least 5 sub-projects in the tree:

 
 

- - GROS: no fancy name yet (low-level toolbox: logging, datatypes).
+ - 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)
  - 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)
 
  - 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).
+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
 
 The tree is not splited 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)
+ 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.
   
  src/Makefile.am     -> main makefile. All projects should fit in only one
                         library (I mean 2, RL+SG), which is compiled here.


@@ -39,7 +42,10 @@ The tree is not splited on projects, but on file finality:
    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.
    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.
  testsuite/ -> The more test the better. 
                Same organization than src/ and include/
                Tests are allowed to load some headers of the module they test.


@@ -52,19 +58,62 @@ The tree is not splited on projects, but on file finality:
  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.
  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 -kr -br -brs -ce -bbo --dont-break-procedure-type --no-tabs
+--cuddle-do-while --cuddle-else --indent-level2 --leave-preprocessor-space
+--no-space-after-function-call-names <myfile>
+
+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:
 **
 ** 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.
+ 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,
 
 SIZE_T
  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)
  
  #include <sys/types.h> in all files manipulating size_t
  do cast it to unsigned long before printing (and use %lu)
  


@@ -72,4 +121,76 @@ PRINTF pointer difference
  printf ("diff = %ld\n", (long) (pointer2 - pointer1));
   
 
  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-<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_<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)
+********************************
+
+* 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
+  desactivate the whole logging mecanism, switching to printfs
+  instead. SimGrid becomes incredibly verbose when doing so, but it
+  you let you fixing the dynars.
\ No newline at end of file