2 ** Source tree organization
4 ******************************************************
6 There is at least 4 sub-projects in the tree:
8 - XBT: eXtended Bundle of Tools (low-level toolbox: logging, datatypes).
9 - SURF: a SimUlation aRtiFact. This is the simulation kernel.
10 - MSG: originally MetaSimGrid, MSG is a simple distributed application
12 - SMPI: Simulated MPI, to run MPI application using emulation technics.
14 They are all in the same tree because they are complementary tools and
15 having all of them in the same package makes the installation easier
16 for end-users. Moreover, it enables to share the compilation chain and
17 eases the development.
19 The tree is not split on projects, but on file finality:
20 include/ -> all *public* headers
21 include/xbt/*.h -> one file per module
23 src/include -> another location for protected headers. Used by SURF, and
24 other should be converted, since this is the Right Thing.
26 testsuite/ -> The more test the better.
27 Same organization than src/ and include/
28 Tests are allowed to load some headers of the module they test.
29 All tests should be listed in run_test.in so that they get
32 examples/ -> Supposed to be copy/pastable by the user, so keep it clear and
33 avoid any kind of trick. In particular, do only include the
36 ** Indentation standard
38 *****************************************************
40 Most files use the Kernighan & Ritchie coding style with 2 spaces of
41 indentation. The indent program can help you to stick to it:
43 indent -kr -l80 -nut -i2 -lps -npcs -br -brs -ce -cdw -bbo -npsl <myfile>
45 The script ./tools/indent runs indent with the appropriate options.
47 FIXME: this list of arguments is still to be discussed, maybe
50 ** Type naming standard
52 *****************************************************
54 It may sound strange, but the type naming convention was source of intense
55 discussion between da SimGrid posse members. The convention we came to may not
56 be the best solution, but it has the merit to exist and leave everyone work.
57 So please stick to it.
59 - ???_t is a valid type (built with typedef)
60 - s_toto_t is a structure (access to fields with .)
61 - s_toto is a structure needing 'struct' keyword to be used
63 - u_toto_t is an union
64 - u_toto is an union needing 'union' keyword to be used
65 - toto_t is an 'object' (struct*)
67 Please to not call toto_t something else than an 'object' (ie, something you
68 have to call _new and _free on it).
71 typedef struct s_toto {} s_toto_t, *toto_t;
72 typedef enum {} e_toto_t;
74 Moreover, only toto_t (and e_toto_t) are public. The rest (mainly s_toto_t)
77 If you see any part of the code not following this convention, this is a
78 bug. Please report it (or fix it yourself if you can).
81 ** Random bits about coding standards and portability
83 *****************************************************
86 Don't use it, or you'll have to check the result (and do some dirty stuff
87 on AIX). Use xbt_malloc (or even better, xbt_new) instead.
89 SIZE_T (FIXME: obsolete?)
90 If possible, avoid size_t and use unsigned long instead. If not,
91 #include <sys/types.h> in all files manipulating size_t
92 do cast it to unsigned long before printing (and use %lu),
95 PRINTF pointer difference (FIXME: advertise %td instead?)
96 printf ("diff = %ld\n", (long) (pointer2 - pointer1));
99 The definition of a inline function must be visible when it is used.
100 As such, an inline function should be defined (an not only declared)
101 in header file (.h) with attributes 'static XBT_INLINE'. It should
102 not be defined in source file (.c).
105 ** Commenting the source: doxygen
107 ****************************************************
109 The global structure of the documentation is in doc/modules.doc
111 The structure of each module (xbt, msg, etc) is in doc/module-<module>.doc
113 The structure of a module is in its public header. This way, you're sure to
114 see all the public interface (and only it). The different parts of the
115 interface are grouped using the @name construct, even if it's buggy. Since
116 parts often get reordered, it's better to add numbers to the parts (so that
117 users can see the intended order).
119 The documentation of each type and macro are also in the public header since
120 this is were they live.
122 The documentation of each function must be in the C file were it lives.
124 Any public element (function, type and macro) must have a @brief part.
127 ** XBT virtualization mechanism (FIXME: this section is deprecated)
129 ****************************************************
131 There is some functionalities that we want to virtualize in XBT. We
132 want xbt_time to give the simulated clock when running on top of the
133 simulator, and the host clock when running on a real system. This
134 could be placed in GRAS (and was, historically), but there is some
135 reason to lower it down to XBT.
137 Here is the used naming scheme:
139 - xbt_<module>_<func>(): functions working both in SG and RL
140 - xbt_os_<module>_<func>(): RL functions usable even in simulator
142 That way, in libsimgrid, we still can use native functions if we
143 want to. It may for example be useful to get the real time when
144 implementing the simulator. Think of the SIGINT handler, which
145 wants to see if the user pressed the key twice in a 5 seconds
146 interval. This is of little use to check the simulated time here.
148 Here is the file layout:
150 - xbt_rl_<module>.c: native implementation (xbt_<module>_<func>()).
151 Simply call the corresponding xbt_os_<module>_<func>.
152 Part only of libgras.so
154 - xbt_sg_<module>.c: SIMIX implementation xbt_<module>_<func>()).
155 Simply call the corresponding SIMIX implementation.
156 Part only of libsimgrid.so
158 - xbt_os_<module>.c: body of the functions implementing natively the
159 stuff (xbt_os_<module>_<func>()).
160 Part of both libgras.so and libsimgrid.so
162 Since there is almost nothing in xbt_rl_module.c and xbt_sg_module.c,
163 it'd be better to use symbol aliasing here (to declare in the object
164 code that the same function have two names), but I'm still
165 investigating the portability of the thing to windows.
169 * SimGrid Hacker Survival Guide (FIXME: should be betterly placed)
170 ********************************
172 * Before pushing any change, don't forget to check if the compilation
173 passes with compiler optimizations and warnings turned on:
174 cmake -Denable_compile_optimizations=ON \
175 -Denable_compile_warnings=ON
177 * If you want to debug memory allocation problems, here are a few hints:
178 - disable compiler optimizations, to have better backtraces;
179 - disable the mallocators, or it will be hard to match malloc's with
181 - disable model checking, unless your problem lies in the model
182 checker part of SimGrid (MC brings its own malloc implementation,
183 which valgrind doesn't understand).
184 All this is configured with:
185 cmake -Denable_model-checking=OFF \
186 -Denable_mallocators=OFF \
187 -Denable_compile_optimizations=OFF
189 * If you break the logs (for example while hacking in the dynars), you
190 want to define XBT_LOG_MAYDAY at the beginning of log.h. It will
191 deactivate the whole logging mechanism, switching to printfs
192 instead. SimGrid becomes incredibly verbose when doing so, but it
193 you let you fixing the dynars.