3 /* gras/datadesc.h - Describing the data you want to exchange */
5 /* Copyright (c) 2003, 2004 Martin Quinson. All rights reserved. */
7 /* This program is free software; you can redistribute it and/or modify it
8 * under the terms of the license (GNU LGPL) which comes with this package. */
10 #ifndef GRAS_DATADESC_H
11 #define GRAS_DATADESC_H
13 #include "xbt/misc.h" /* SG_BEGIN_DECL */
14 #include "xbt/dynar.h" /* void_f_pvoid_t */
18 /** @addtogroup GRAS_dd Data description
19 * @brief Describing data to be exchanged
21 * Since GRAS takes care of potential representation conversion when the platform is heterogeneous,
22 * any data which transits on the network must be described beforehand.
24 * There is several possible interfaces for this, ranging from the really completely automatic parsing to
25 * completely manual. Let's study each of them from the simplest to the more advanced:
27 * - Section \ref GRAS_dd_basic presents how to retrieve and use an already described type.
28 * - Section \ref GRAS_dd_auto shows how to get GRAS parsing your type description automagically. This
29 * is unfortunately not always possible (only works for some structures), but if it is for your data,
30 * this is definitly the way to go.
31 * - Section \ref GRAS_dd_manual presents how to build a description manually. This is useful when you want
32 * to describe an array or a pointer of pre-defined structures.
33 * - You sometimes need to exchange informations between descriptions at send or receive time. This is
34 * for example useful when your structure contains an array which size is given by another field of the
36 * - Section \ref GRAS_dd_cb_simple provides a simple interface to do so, allowing to share integers stored on a stack.
37 * - Section \ref GRAS_dd_cb_full provides a full featured interface to do so, but it may reveal somehow difficult to use.
40 /** @defgroup GRAS_dd_basic Basic operations on data descriptions
42 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Basics" --> \endhtmlonly
44 * If you only want to send pre-existing types, simply retrieve the pre-defined description with
45 * the \ref gras_datadesc_by_name function. Existing types entail:
46 * - char (both signed and unsigned)
47 * - int (short, regular, long and long long, both signed and unsigned)
49 * - string (which is indeed a reference to a dynamically sized array of char, strlen being used to retrieve the size)
51 * Example:\verbatim gras_datadesc_type_t i = gras_datadesc_by_name("int");
52 gras_datadesc_type_t uc = gras_datadesc_by_name("unsigned char");
53 gras_datadesc_type_t str = gras_datadesc_by_name("string");\endverbatim
58 /** @brief Opaque type describing a type description. */
59 typedef struct s_gras_datadesc_type *gras_datadesc_type_t;
61 /** \brief Search a type description from its name */
62 XBT_PUBLIC(gras_datadesc_type_t) gras_datadesc_by_name(const char *name);
63 XBT_PUBLIC(gras_datadesc_type_t) gras_datadesc_by_name_or_null(const char *name);
67 /** @defgroup GRAS_dd_auto Automatic parsing of data descriptions
69 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Automatic parsing" --> \endhtmlonly
71 * If you need to declare a new datatype, this is the simplest way to describe it to GRAS. Simply
72 * enclose its type definition into a \ref GRAS_DEFINE_TYPE macro call, and you're set. Here is
73 * an type declaration example: \verbatim GRAS_DEFINE_TYPE(mytype,struct mytype {
77 * The type is then both copied verbatim into your source file and stored for further parsing. This allows
78 * you to let GRAS parse the exact version you are actually using in your program.
79 * You can then retrieve the corresponding type description with \ref gras_datadesc_by_symbol.
80 * Don't worry too much for the performances, the type is only parsed once and a binary representation
81 * is stored and used in any subsequent calls.
83 * If your structure contains any pointer, you have to explain GRAS the size of the pointed array. This
84 * can be 1 in the case of simple references, or more in the case of regular arrays. For that, use the
85 * \ref GRAS_ANNOTE macro within the type declaration you are passing to \ref GRAS_DEFINE_TYPE. This macro
86 * rewrites itself to nothing in the declaration (so they won't pollute the type definition copied verbatim
87 * into your code), and give some information to GRAS about your pointer.
89 * GRAS_ANNOTE takes two arguments being the key name and the key value. For now, the only accepted key name
90 * is "size", to specify the length of the pointed array. It can either be:
91 * - the string "1" (without the quote),
92 * - the name of another field of the structure
93 * - a sort of computed expression for multidimensional arrays (see below -- pay attention to the warnings below).
95 * Here is an example:\verbatim GRAS_DEFINE_TYPE(s_clause,
98 struct s_array *father GRAS_ANNOTE(size,1);
100 int *data GRAS_ANNOTE(size,length);
103 int *matrix GRAS_ANNOTE(size,rows*cols);
106 * It specifies that the structure s_array contains six fields, that the \a name field is a classical null-terminated
107 * char* string (#xbt_string_t is just an helper type defined exactly to help the parsing macro to specify the semantic of the pointer),
108 * that \a father field is a simple reference, that the size of the array pointed by \a data is the \a length field, and that the
109 * \a matrix field is an arraywhich size is the result of \a rows times \a cols.
111 * \warning Since GRAS_DEFINE_TYPE is a macro, you shouldn't put any comma in your type definition
112 * (comma separates macro args). For example, change \verbatim int a, b;\endverbatim to \verbatim int a;
115 * \section gras_dd_define \#define and fixed size array
117 * If you want to exchange arrays which size is given at compilation time by a
118 * \#defined constant, you need to keep GRAS informed. It would be done the
121 \verbatim #define BLOCK_SIZE 32
122 GRAS_DEFINE_TYPE(s_toto,
124 double data[BLOCK_SIZE];
127 void register_messages() {
128 gras_datadesc_type_t toto_type;
130 gras_datadesc_set_const("BLOCK_SIZE",BLOCK_SIZE);
131 toto_type = gras_datadesc_by_symbol(s_toto);
134 * The form <tt>gras_datadesc_set_const("BLOCK_SIZE",BLOCK_SIZE);</tt> ensures
135 * that when you change the definition of the constant, GRAS keeps informed of
136 * the right value. Passing the numerical value of the constant as second
137 * argument would be a bad idea to that regard. Of course, the call to
138 * gras_datadesc_set_const() should come before any gras_datadesc_by_symbol()
139 * containing references to it.
141 * \section GRAS_dd_multidim Defining multidimentional arrays
143 * The mecanism for multidimensional arrays is known to be fragile and cumbersome. If you want to use it,
144 * you have to understand how it is implemented: the multiplication is performed using the sizes stack. In previous example,
145 * a \ref gras_datadesc_cb_push_int callback is added to the \a rows field and a \ref gras_datadesc_cb_push_int_mult one is
146 * added to \a cols. So, when the structure is sent, the \a rows field push its value onto the stack, then the \a cols field
147 * retrieve this value from the stack, compute (and push) the multiplication value. The \a matrix field can then retrieve this
148 * value by poping the array. There is several ways for this to go wrong:
149 * - if the matrix field is placed before the sizes, the right value won't get pushed into the stack soon enough.
150 * Reorder your structure fields if needed.
151 * - if you write GRAS_ANNOTE(size,cols*rows); in previous example (inverting rows and cols in annotation),
152 * \a rows will be given a \ref gras_datadesc_cb_push_int_mult. This cannot work since it will try to
153 * pop the value which will be pushed by \a cols <i>afterward</i>.
154 * - if you have more than one matrix in your structure, don't interleave the size. They are pushed/poped in the structure order.
155 * - if some of the sizes are used in more than one matrix, you cannot use this mecanism -- sorry.
157 * If you cannot express your datadescs with this mechanism, you'll have to use the more advanced
158 * (and somehow complex) one described in the \ref GRAS_dd_cb_full.
160 * \section GRAS_dd_multifile Projects spanning over multiple files
162 * GRAS_DEFINE_TYPE declares some symbols to work, it needs some special
163 * care when used in several files. In such case, you want the regular type
164 * definition in all files, but the gras specific symbol defined in only
165 * one file. For example, consider the following gras project sketch.
167 \verbatim #include <gras.h>
169 GRAS_DEFINE_TYPE(my_type,struct my_type {
175 int client(int argc, char *argv[]) {
179 int server(int argc, char *argv[]) {
183 * If you want to split this in two files (one for each kind of processes),
184 * you need to put the GRAS_DEFINE_TYPE block in a separate header (so that
185 * each process kind see the associated C type definition). But
186 * then you cannot include this right away in all files because the extra
187 * symbols containing the GRAS definition would be dupplicated.
189 * You thus have to decide in which C file the symbols will live. In that
190 * file, include the header without restriction:
192 \verbatim #include "my_header.h"
194 int client(int argc, char *argv[]) {
198 * And in the other files needing the C definitions without the extra GRAS
199 * symbols, declare the symbol GRAS_DEFINE_TYPE_EXTERN before loading gras.h:
201 \verbatim #define GRAS_DEFINE_TYPE_EXTERN
203 #include "my_header.h"
205 int server(int argc, char *argv[]) {
210 * Sometimes, the situation is even more complicated: There is some shared
211 * messages that you want to see from every file, and some private messages
212 * that you want to be defined only in one C file.
213 * In that case, use the previous trick for common messages, and use
214 * #GRAS_DEFINE_TYPE_LOCAL for the private messages.
216 * For now, there is no way to have semi-private symbols (for example shared
217 * in all files of a library), sorry. Use functions as interface to your
218 * library instead of publishing directly the messages.
224 /** @brief Automatically parse C code
227 #define GRAS_DEFINE_TYPE(name,def) \
228 const char * _gras_this_type_symbol_does_not_exist__##name=#def; def
230 #ifndef DOXYGEN_SKIP /* doxygen don't like macro fun too much */
231 # ifdef GRAS_DEFINE_TYPE_EXTERN
232 # undef GRAS_DEFINE_TYPE
233 # define GRAS_DEFINE_TYPE(name,def) def
234 # undef GRAS_DEFINE_TYPE_EXTERN
238 /** @brief if this symbol is defined, the \a GRAS_DEFINE_TYPE symbols live in another file.
241 #define GRAS_DEFINE_TYPE_EXTERN 1
242 /* leave the fun of declaring this to the user */
243 #undef GRAS_DEFINE_TYPE_EXTERN
245 /** @brief Define a symbol to be automatically parsed, disregarding #GRAS_DEFINE_TYPE_EXTERN
248 * Call this macro instead of #GRAS_DEFINE_TYPE if you had to define #GRAS_DEFINE_TYPE_EXTERN
249 * to load some external symbols, but if you now want to automatically parse the content of
250 * your private messages.
252 #define GRAS_DEFINE_TYPE_LOCAL(name, def) \
253 const char * _gras_this_type_symbol_does_not_exist__##name=#def; def
255 /** @brief Retrieve a datadesc which was previously parsed
258 #define gras_datadesc_by_symbol(name) \
259 (gras_datadesc_by_name_or_null(#name) ? \
260 gras_datadesc_by_name_or_null(#name) : \
261 gras_datadesc_parse(#name, \
262 _gras_this_type_symbol_does_not_exist__##name) \
266 * @brief Add an annotation to a type to be automatically parsed
268 #define GRAS_ANNOTE(key,val)
270 /** @brief Defines the value of a define to the datatype parsing infrastructure
272 XBT_PUBLIC(void) gras_datadesc_set_const(const char*name, int value);
276 XBT_PUBLIC(gras_datadesc_type_t)
277 gras_datadesc_parse(const char *name, const char *C_statement);
279 /** @defgroup GRAS_dd_manual Simple manual data description
282 * Here are the functions to use if you want to declare your description manually.
283 * The function names should be self-explanatory in most cases.
285 * You can add callbacks to the datatypes doing any kind of action you may want. Usually,
286 * pre-send callbacks are used to prepare the type expedition while post-receive callbacks
287 * are used to fix any issue after the receive.
289 * If your types are dynamic, you'll need to add some extra callback. For example, there is a
290 * specific callback for the string type which is in charge of computing the length of the char
291 * array. This is done with the cbps mechanism, explained in next section.
293 * If your types may contain pointer cycle, you must specify it to GRAS using the @ref gras_datadesc_cycle_set.
298 unsigned long int l1;
300 unsigned long int l2;
303 my_type=gras_datadesc_struct("mystruct");
304 gras_datadesc_struct_append(my_type,"c1", gras_datadesc_by_name("unsigned char"));
305 gras_datadesc_struct_append(my_type,"l1", gras_datadesc_by_name("unsigned long"));
306 gras_datadesc_struct_append(my_type,"c2", gras_datadesc_by_name("unsigned char"));
307 gras_datadesc_struct_append(my_type,"l2", gras_datadesc_by_name("unsigned long int"));
308 gras_datadesc_struct_close(my_type);
310 my_type=gras_datadesc_ref("mystruct*", gras_datadesc_by_name("mystruct"));
312 [Use my_type to send pointers to mystruct data]\endverbatim
317 /** \brief Opaque type describing a type description callback persistant state. */
318 typedef struct s_gras_cbps *gras_cbps_t;
320 /* callbacks prototypes */
321 /** \brief Prototype of type callbacks returning nothing. */
322 typedef void (*gras_datadesc_type_cb_void_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
323 /** \brief Prototype of type callbacks returning an int. */
324 typedef int (*gras_datadesc_type_cb_int_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
325 /** \brief Prototype of type callbacks selecting a type. */
326 typedef gras_datadesc_type_t (*gras_datadesc_selector_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
329 /******************************************
330 **** Declare datadescription yourself ****
331 ******************************************/
333 XBT_PUBLIC(gras_datadesc_type_t) gras_datadesc_struct(const char *name);
334 XBT_PUBLIC(void) gras_datadesc_struct_append(gras_datadesc_type_t struct_type,
336 gras_datadesc_type_t field_type);
337 XBT_PUBLIC(void) gras_datadesc_struct_close(gras_datadesc_type_t struct_type);
340 XBT_PUBLIC(gras_datadesc_type_t) gras_datadesc_union(const char *name,
341 gras_datadesc_type_cb_int_t selector);
342 XBT_PUBLIC(void) gras_datadesc_union_append(gras_datadesc_type_t union_type,
344 gras_datadesc_type_t field_type);
345 XBT_PUBLIC(void) gras_datadesc_union_close(gras_datadesc_type_t union_type);
348 XBT_PUBLIC(gras_datadesc_type_t)
349 gras_datadesc_ref(const char *name,
350 gras_datadesc_type_t referenced_type);
351 XBT_PUBLIC(gras_datadesc_type_t)
352 gras_datadesc_ref_generic(const char *name,
353 gras_datadesc_selector_t selector);
355 XBT_PUBLIC(gras_datadesc_type_t)
356 gras_datadesc_array_fixed(const char *name,
357 gras_datadesc_type_t element_type,
358 long int fixed_size);
359 XBT_PUBLIC(gras_datadesc_type_t)
360 gras_datadesc_array_dyn(const char *name,
361 gras_datadesc_type_t element_type,
362 gras_datadesc_type_cb_int_t dynamic_size);
363 XBT_PUBLIC(gras_datadesc_type_t)
364 gras_datadesc_ref_pop_arr(gras_datadesc_type_t element_type);
366 XBT_PUBLIC(gras_datadesc_type_t)
367 gras_datadesc_dynar(gras_datadesc_type_t elm_t,
368 void_f_pvoid_t *free_func);
369 XBT_PUBLIC(gras_datadesc_type_t)
370 gras_datadesc_matrix(gras_datadesc_type_t elm_t,
371 void_f_pvoid_t * const free_f);
373 /*********************************
374 * Change stuff within datadescs *
375 *********************************/
377 /** \brief Specify that this type may contain cycles */
378 XBT_PUBLIC(void) gras_datadesc_cycle_set(gras_datadesc_type_t type);
379 /** \brief Specify that this type do not contain any cycles (default) */
380 XBT_PUBLIC(void) gras_datadesc_cycle_unset(gras_datadesc_type_t type);
381 /** \brief Add a pre-send callback to this datadesc. */
382 XBT_PUBLIC(void) gras_datadesc_cb_send (gras_datadesc_type_t type,
383 gras_datadesc_type_cb_void_t pre);
384 /** \brief Add a post-receive callback to this datadesc.*/
385 XBT_PUBLIC(void) gras_datadesc_cb_recv(gras_datadesc_type_t type,
386 gras_datadesc_type_cb_void_t post);
387 /** \brief Add a pre-send callback to the given field of the datadesc */
388 XBT_PUBLIC(void) gras_datadesc_cb_field_send (gras_datadesc_type_t type,
389 const char *field_name,
390 gras_datadesc_type_cb_void_t pre);
391 /** \brief Add a post-receive callback to the given field of the datadesc */
392 XBT_PUBLIC(void) gras_datadesc_cb_field_recv(gras_datadesc_type_t type,
393 const char *field_name,
394 gras_datadesc_type_cb_void_t post);
395 /** \brief Add a pre-send callback to the given field resulting in its value to be pushed */
396 XBT_PUBLIC(void) gras_datadesc_cb_field_push (gras_datadesc_type_t type,
397 const char *field_name);
398 /** \brief Add a pre-send callback to the given field resulting in its value multiplied to any previously pushed value and then pushed back */
399 XBT_PUBLIC(void) gras_datadesc_cb_field_push_multiplier (gras_datadesc_type_t type,
400 const char *field_name);
402 /******************************
403 * Get stuff within datadescs *
404 ******************************/
405 /** \brief Returns the name of a datadescription */
406 XBT_PUBLIC(const char *) gras_datadesc_get_name(gras_datadesc_type_t ddt);
407 /** \brief Returns the identifier of a datadescription */
408 XBT_PUBLIC(int) gras_datadesc_get_id(gras_datadesc_type_t ddt);
412 /** @defgroup GRAS_dd_cb_simple Data description with Callback Persistant State: Simple push/pop mechanism
415 * Sometimes, one of the callbacks need to leave information for the next ones. If this is a simple integer (such as
416 * an array size), you can use the functions described here. If not, you'll have to play with the complete cbps interface.
418 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Simple push/pop Callback State" -->\endhtmlonly
420 * Here is an example:\verbatim
426 my_type=gras_datadesc_struct("s_array");
427 gras_datadesc_struct_append(my_type,"length", gras_datadesc_by_name("int"));
428 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int);
430 gras_datadesc_struct_append(my_type,"data",
431 gras_datadesc_array_dyn ("s_array::data",gras_datadesc_by_name("int"), gras_datadesc_cb_pop));
432 gras_datadesc_struct_close(my_type);
436 * The *_mult versions are intended for multi-dimensional arrays: They multiply their value to the previously pushed one
437 * (by another field callback) and push the result of the multiplication back. An example of use follows. Please note
438 * that the first field needs a regular push callback, not a multiplier one. Think of it as a stacked calculator (man dc(1)).\verbatim
445 my_type=gras_datadesc_struct("s_matrix");
446 gras_datadesc_struct_append(my_type,"row", gras_datadesc_by_name("int"));
447 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int);
448 gras_datadesc_struct_append(my_type,"col", gras_datadesc_by_name("int"));
449 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int_mult);
451 gras_datadesc_struct_append(my_type,"data",
452 gras_datadesc_array_dyn ("s_matrix::data",gras_datadesc_by_name("int"), gras_datadesc_cb_pop));
453 gras_datadesc_struct_close(my_type);
460 gras_cbps_i_push(gras_cbps_t ps, int val);
462 gras_cbps_i_pop(gras_cbps_t ps);
464 XBT_PUBLIC(int) gras_datadesc_cb_pop(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
466 XBT_PUBLIC(void) gras_datadesc_cb_push_int(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
467 XBT_PUBLIC(void) gras_datadesc_cb_push_uint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
468 XBT_PUBLIC(void) gras_datadesc_cb_push_lint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
469 XBT_PUBLIC(void) gras_datadesc_cb_push_ulint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
471 XBT_PUBLIC(void) gras_datadesc_cb_push_int_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
472 XBT_PUBLIC(void) gras_datadesc_cb_push_uint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
473 XBT_PUBLIC(void) gras_datadesc_cb_push_lint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
474 XBT_PUBLIC(void) gras_datadesc_cb_push_ulint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
479 /** @defgroup GRAS_dd_cb_full Data description with Callback Persistant State: Full featured interface
482 * Sometimes, one of the callbacks need to leave information for the next
483 * ones. If the simple push/pop mechanism introduced in previous section
484 * isn't enough, you can always use this full featured one. The bad point is
485 * that it is quite badly documented...
487 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Full featured Callback State" -->\endhtmlonly
493 XBT_PUBLIC(void) gras_cbps_v_pop (gras_cbps_t ps,
495 /* OUT */ gras_datadesc_type_t *ddt,
496 /* OUT */ void **res);
497 XBT_PUBLIC(void) gras_cbps_v_push(gras_cbps_t ps,
500 gras_datadesc_type_t ddt);
501 XBT_PUBLIC(void) gras_cbps_v_set (gras_cbps_t ps,
504 gras_datadesc_type_t ddt);
506 XBT_PUBLIC(void*) gras_cbps_v_get (gras_cbps_t ps,
508 /* OUT */ gras_datadesc_type_t *ddt);
510 XBT_PUBLIC(void) gras_cbps_block_begin(gras_cbps_t ps);
511 XBT_PUBLIC(void) gras_cbps_block_end(gras_cbps_t ps);
517 /*******************************
518 **** About data convertion ****
519 *******************************/
520 XBT_PUBLIC(int) gras_arch_selfid(void); /* ID of this arch */
523 /*****************************
524 **** NWS datadescription * FIXME: obsolete?
525 *****************************/
528 * Basic types we can embeed in DataDescriptors.
531 {CHAR_TYPE, DOUBLE_TYPE, FLOAT_TYPE, INT_TYPE, LONG_TYPE, SHORT_TYPE,
532 UNSIGNED_INT_TYPE, UNSIGNED_LONG_TYPE, UNSIGNED_SHORT_TYPE, STRUCT_TYPE}
534 #define SIMPLE_TYPE_COUNT 9
536 /** \brief Describe a collection of data.
538 ** A description of a collection of \a type data. \a repetitions is used only
539 ** for arrays; it contains the number of elements. \a offset is used only for
540 ** struct members in host format; it contains the offset of the member from the
541 ** beginning of the struct, taking into account internal padding added by the
542 ** compiler for alignment purposes. \a members, \a length, and \a tailPadding are
543 ** used only for STRUCT_TYPE data; the \a length -long array \a members describes
544 ** the members of the nested struct, and \a tailPadding indicates how many
545 ** padding bytes the compiler adds to the end of the structure.
548 typedef struct DataDescriptorStruct {
552 /*@null@*/ struct DataDescriptorStruct *members;
556 /** DataDescriptor for an array */
557 #define SIMPLE_DATA(type,repetitions) \
558 {type, repetitions, 0, NULL, 0, 0}
559 /** DataDescriptor for an structure member */
560 #define SIMPLE_MEMBER(type,repetitions,offset) \
561 {type, repetitions, offset, NULL, 0, 0}
562 /** DataDescriptor for padding bytes */
563 #define PAD_BYTES(structType,lastMember,memberType,repetitions) \
564 sizeof(structType) - offsetof(structType, lastMember) - \
565 sizeof(memberType) * repetitions
567 XBT_PUBLIC(gras_datadesc_type_t)
568 gras_datadesc_import_nws(const char *name,
569 const DataDescriptor *desc,
570 unsigned long howmany);
575 #endif /* GRAS_DATADESC_H */