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,
97 struct s_array *father GRAS_ANNOTE(size,1);
99 int *data GRAS_ANNOTE(size,length);
102 int *matrix GRAS_ANNOTE(size,rows*cols);
105 * It specifies that the structure s_array contains five fields, that the \a father field is a simple reference,
106 * that the size of the array pointed by \a data is the \a length field, and that the \a matrix field is an array
107 * which size is the result of \a rows times \a cols.
109 * \warning Since GRAS_DEFINE_TYPE is a macro, you shouldn't put any comma in your type definition
110 * (comma separates macro args). For example, change \verbatim int a, b;\endverbatim to \verbatim int a;
113 * \section gras_dd_define \#define and fixed size array
115 * If you want to exchange arrays which size is given at compilation time by a
116 * \#defined constant, you need to keep GRAS informed. It would be done the
119 \verbatim #define BLOCK_SIZE 32
120 GRAS_DEFINE_TYPE(s_toto,
122 double data[BLOCK_SIZE];
125 void register_messages() {
126 gras_datadesc_type_t toto_type;
128 gras_datadesc_set_const("BLOCK_SIZE",BLOCK_SIZE);
129 toto_type = gras_datadesc_by_symbol(s_toto);
132 * The form <tt>gras_datadesc_set_const("BLOCK_SIZE",BLOCK_SIZE);</tt> ensures
133 * that when you change the definition of the constant, GRAS keeps informed of
134 * the right value. Passing the numerical value of the constant as second
135 * argument would be a bad idea to that regard. Of course, the call to
136 * gras_datadesc_set_const() should come before any gras_datadesc_by_symbol()
137 * containing references to it.
139 * \section GRAS_dd_multidim Defining multidimentional arrays
141 * The mecanism for multidimensional arrays is known to be fragile and cumbersome. If you want to use it,
142 * you have to understand how it is implemented: the multiplication is performed using the sizes stack. In previous example,
143 * 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
144 * 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
145 * retrieve this value from the stack, compute (and push) the multiplication value. The \a matrix field can then retrieve this
146 * value by poping the array. There is several ways for this to go wrong:
147 * - if the matrix field is placed before the sizes, the right value won't get pushed into the stack soon enough.
148 * Reorder your structure fields if needed.
149 * - if you write GRAS_ANNOTE(size,cols*rows); in previous example (inverting rows and cols in annotation),
150 * \a rows will be given a \ref gras_datadesc_cb_push_int_mult. This cannot work since it will try to
151 * pop the value which will be pushed by \a cols <i>afterward</i>.
152 * - if you have more than one matrix in your structure, don't interleave the size. They are pushed/poped in the structure order.
153 * - if some of the sizes are used in more than one matrix, you cannot use this mecanism -- sorry.
155 * If you cannot express your datadescs with this mechanism, you'll have to use the more advanced
156 * (and somehow complex) one described in the \ref GRAS_dd_cb_full.
158 * \section GRAS_dd_multifile Projects spanning over multiple files
160 * GRAS_DEFINE_TYPE declares some symbols to work, it needs some special
161 * care when used in several files. In such case, you want the regular type
162 * definition in all files, but the gras specific symbol defined in only
163 * one file. For example, consider the following gras project sketch.
165 \verbatim #include <gras.h>
167 GRAS_DEFINE_TYPE(my_type,struct my_type {
173 int client(int argc, char *argv[]) {
177 int server(int argc, char *argv[]) {
181 * If you want to split this in two files (one for each kind of processes),
182 * you need to put the GRAS_DEFINE_TYPE block in a separate header. But
183 * then you cannot include this right away in all files because the extra
184 * symbols would be defined in dupplicate.
186 * You thus have to decide in which file the symbols will live. In that
187 * file, include the header without restriction:
189 \verbatim #include "my_header.h"
191 int client(int argc, char *argv[]) {
195 * And in the other files needing the C definitions without the extra GRAS
196 * symbols, declare the symbol GRAS_DEFINE_TYPE_EXTERN before:
198 \verbatim #define GRAS_DEFINE_TYPE_EXTERN
199 #include "my_header.h"
201 int server(int argc, char *argv[]) {
210 /** @brief Automatically parse C code
213 #define GRAS_DEFINE_TYPE(name,def) \
214 const char * _gras_this_type_symbol_does_not_exist__##name=#def; def
216 #ifndef DOXYGEN_SKIP /* doxygen don't like macro fun too much */
217 # ifdef GRAS_DEFINE_TYPE_EXTERN
218 # undef GRAS_DEFINE_TYPE
219 # define GRAS_DEFINE_TYPE(name,def) def
220 # undef GRAS_DEFINE_TYPE_EXTERN
224 /** @brief if this symbol is defined, the \a GRAS_DEFINE_TYPE symbols live in another file.
227 #define GRAS_DEFINE_TYPE_EXTERN 1
231 /** @brief Retrieve a datadesc which was previously parsed
234 #define gras_datadesc_by_symbol(name) \
235 (gras_datadesc_by_name_or_null(#name) ? \
236 gras_datadesc_by_name_or_null(#name) : \
237 gras_datadesc_parse(#name, \
238 _gras_this_type_symbol_does_not_exist__##name) \
242 * @brief Add an annotation to a type to be automatically parsed
244 #define GRAS_ANNOTE(key,val)
246 /** @brief Defines the value of a define to the datatype parsing infrastructure
248 XBT_PUBLIC void gras_datadesc_set_const(const char*name, int value);
252 XBT_PUBLIC gras_datadesc_type_t
253 gras_datadesc_parse(const char *name, const char *C_statement);
255 /** @defgroup GRAS_dd_manual Simple manual data description
258 * Here are the functions to use if you want to declare your description manually.
259 * The function names should be self-explanatory in most cases.
261 * You can add callbacks to the datatypes doing any kind of action you may want. Usually,
262 * pre-send callbacks are used to prepare the type expedition while post-receive callbacks
263 * are used to fix any issue after the receive.
265 * If your types are dynamic, you'll need to add some extra callback. For example, there is a
266 * specific callback for the string type which is in charge of computing the length of the char
267 * array. This is done with the cbps mechanism, explained in next section.
269 * If your types may contain pointer cycle, you must specify it to GRAS using the @ref gras_datadesc_cycle_set.
274 unsigned long int l1;
276 unsigned long int l2;
279 my_type=gras_datadesc_struct("mystruct");
280 gras_datadesc_struct_append(my_type,"c1", gras_datadesc_by_name("unsigned char"));
281 gras_datadesc_struct_append(my_type,"l1", gras_datadesc_by_name("unsigned long"));
282 gras_datadesc_struct_append(my_type,"c2", gras_datadesc_by_name("unsigned char"));
283 gras_datadesc_struct_append(my_type,"l2", gras_datadesc_by_name("unsigned long int"));
284 gras_datadesc_struct_close(my_type);
286 my_type=gras_datadesc_ref("mystruct*", gras_datadesc_by_name("mystruct"));
288 [Use my_type to send pointers to mystruct data]\endverbatim
293 /** \brief Opaque type describing a type description callback persistant state. */
294 typedef struct s_gras_cbps *gras_cbps_t;
296 /* callbacks prototypes */
297 /** \brief Prototype of type callbacks returning nothing. */
298 typedef void (*gras_datadesc_type_cb_void_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
299 /** \brief Prototype of type callbacks returning an int. */
300 typedef int (*gras_datadesc_type_cb_int_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
301 /** \brief Prototype of type callbacks selecting a type. */
302 typedef gras_datadesc_type_t (*gras_datadesc_selector_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
305 /******************************************
306 **** Declare datadescription yourself ****
307 ******************************************/
309 XBT_PUBLIC gras_datadesc_type_t gras_datadesc_struct(const char *name);
310 XBT_PUBLIC void gras_datadesc_struct_append(gras_datadesc_type_t struct_type,
312 gras_datadesc_type_t field_type);
313 XBT_PUBLIC void gras_datadesc_struct_close(gras_datadesc_type_t struct_type);
316 XBT_PUBLIC gras_datadesc_type_t gras_datadesc_union(const char *name,
317 gras_datadesc_type_cb_int_t selector);
318 XBT_PUBLIC void gras_datadesc_union_append(gras_datadesc_type_t union_type,
320 gras_datadesc_type_t field_type);
321 XBT_PUBLIC void gras_datadesc_union_close(gras_datadesc_type_t union_type);
324 XBT_PUBLIC gras_datadesc_type_t
325 gras_datadesc_ref(const char *name,
326 gras_datadesc_type_t referenced_type);
327 XBT_PUBLIC gras_datadesc_type_t
328 gras_datadesc_ref_generic(const char *name,
329 gras_datadesc_selector_t selector);
331 XBT_PUBLIC gras_datadesc_type_t
332 gras_datadesc_array_fixed(const char *name,
333 gras_datadesc_type_t element_type,
334 long int fixed_size);
335 XBT_PUBLIC gras_datadesc_type_t
336 gras_datadesc_array_dyn(const char *name,
337 gras_datadesc_type_t element_type,
338 gras_datadesc_type_cb_int_t dynamic_size);
339 XBT_PUBLIC gras_datadesc_type_t
340 gras_datadesc_ref_pop_arr(gras_datadesc_type_t element_type);
342 XBT_PUBLIC gras_datadesc_type_t
343 gras_datadesc_dynar(gras_datadesc_type_t elm_t,
344 void_f_pvoid_t *free_func);
345 XBT_PUBLIC gras_datadesc_type_t
346 gras_datadesc_matrix(gras_datadesc_type_t elm_t,
347 void_f_pvoid_t * const free_f);
349 /*********************************
350 * Change stuff within datadescs *
351 *********************************/
353 /** \brief Specify that this type may contain cycles */
354 XBT_PUBLIC void gras_datadesc_cycle_set(gras_datadesc_type_t type);
355 /** \brief Specify that this type do not contain any cycles (default) */
356 XBT_PUBLIC void gras_datadesc_cycle_unset(gras_datadesc_type_t type);
357 /** \brief Add a pre-send callback to this datadesc. */
358 XBT_PUBLIC void gras_datadesc_cb_send (gras_datadesc_type_t type,
359 gras_datadesc_type_cb_void_t pre);
360 /** \brief Add a post-receive callback to this datadesc.*/
361 XBT_PUBLIC void gras_datadesc_cb_recv(gras_datadesc_type_t type,
362 gras_datadesc_type_cb_void_t post);
363 /** \brief Add a pre-send callback to the given field of the datadesc */
364 XBT_PUBLIC void gras_datadesc_cb_field_send (gras_datadesc_type_t type,
365 const char *field_name,
366 gras_datadesc_type_cb_void_t pre);
367 /** \brief Add a post-receive callback to the given field of the datadesc */
368 XBT_PUBLIC void gras_datadesc_cb_field_recv(gras_datadesc_type_t type,
369 const char *field_name,
370 gras_datadesc_type_cb_void_t post);
371 /** \brief Add a pre-send callback to the given field resulting in its value to be pushed */
372 XBT_PUBLIC void gras_datadesc_cb_field_push (gras_datadesc_type_t type,
373 const char *field_name);
374 /** \brief Add a pre-send callback to the given field resulting in its value multiplied to any previously pushed value and then pushed back */
375 XBT_PUBLIC void gras_datadesc_cb_field_push_multiplier (gras_datadesc_type_t type,
376 const char *field_name);
378 /******************************
379 * Get stuff within datadescs *
380 ******************************/
381 /** \brief Returns the name of a datadescription */
382 XBT_PUBLIC const char * gras_datadesc_get_name(gras_datadesc_type_t ddt);
383 /** \brief Returns the identifier of a datadescription */
384 XBT_PUBLIC int gras_datadesc_get_id(gras_datadesc_type_t ddt);
388 /** @defgroup GRAS_dd_cb_simple Data description with Callback Persistant State: Simple push/pop mechanism
391 * Sometimes, one of the callbacks need to leave information for the next ones. If this is a simple integer (such as
392 * an array size), you can use the functions described here. If not, you'll have to play with the complete cbps interface.
394 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Simple push/pop Callback State" -->\endhtmlonly
396 * Here is an example:\verbatim
402 my_type=gras_datadesc_struct("s_array");
403 gras_datadesc_struct_append(my_type,"length", gras_datadesc_by_name("int"));
404 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int);
406 gras_datadesc_struct_append(my_type,"data",
407 gras_datadesc_array_dyn ("s_array::data",gras_datadesc_by_name("int"), gras_datadesc_cb_pop));
408 gras_datadesc_struct_close(my_type);
412 * The *_mult versions are intended for multi-dimensional arrays: They multiply their value to the previously pushed one
413 * (by another field callback) and push the result of the multiplication back. An example of use follows. Please note
414 * that the first field needs a regular push callback, not a multiplier one. Think of it as a stacked calculator (man dc(1)).\verbatim
421 my_type=gras_datadesc_struct("s_matrix");
422 gras_datadesc_struct_append(my_type,"row", gras_datadesc_by_name("int"));
423 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int);
424 gras_datadesc_struct_append(my_type,"col", gras_datadesc_by_name("int"));
425 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int_mult);
427 gras_datadesc_struct_append(my_type,"data",
428 gras_datadesc_array_dyn ("s_matrix::data",gras_datadesc_by_name("int"), gras_datadesc_cb_pop));
429 gras_datadesc_struct_close(my_type);
436 gras_cbps_i_push(gras_cbps_t ps, int val);
438 gras_cbps_i_pop(gras_cbps_t ps);
440 XBT_PUBLIC int gras_datadesc_cb_pop(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
442 XBT_PUBLIC void gras_datadesc_cb_push_int(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
443 XBT_PUBLIC void gras_datadesc_cb_push_uint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
444 XBT_PUBLIC void gras_datadesc_cb_push_lint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
445 XBT_PUBLIC void gras_datadesc_cb_push_ulint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
447 XBT_PUBLIC void gras_datadesc_cb_push_int_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
448 XBT_PUBLIC void gras_datadesc_cb_push_uint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
449 XBT_PUBLIC void gras_datadesc_cb_push_lint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
450 XBT_PUBLIC void gras_datadesc_cb_push_ulint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
455 /** @defgroup GRAS_dd_cb_full Data description with Callback Persistant State: Full featured interface
458 * Sometimes, one of the callbacks need to leave information for the next
459 * ones. If the simple push/pop mechanism introduced in previous section
460 * isn't enough, you can always use this full featured one. The bad point is
461 * that it is quite badly documented...
463 * \htmlonly <!-- DOXYGEN_NAVBAR_LABEL="Full featured Callback State" -->\endhtmlonly
469 XBT_PUBLIC void gras_cbps_v_pop (gras_cbps_t ps,
471 /* OUT */ gras_datadesc_type_t *ddt,
472 /* OUT */ void **res);
473 XBT_PUBLIC void gras_cbps_v_push(gras_cbps_t ps,
476 gras_datadesc_type_t ddt);
477 XBT_PUBLIC void gras_cbps_v_set (gras_cbps_t ps,
480 gras_datadesc_type_t ddt);
482 XBT_PUBLIC void * gras_cbps_v_get (gras_cbps_t ps,
484 /* OUT */ gras_datadesc_type_t *ddt);
486 XBT_PUBLIC void gras_cbps_block_begin(gras_cbps_t ps);
487 XBT_PUBLIC void gras_cbps_block_end(gras_cbps_t ps);
493 /*******************************
494 **** About data convertion ****
495 *******************************/
496 XBT_PUBLIC int gras_arch_selfid(void); /* ID of this arch */
499 /*****************************
500 **** NWS datadescription * FIXME: obsolete?
501 *****************************/
504 * Basic types we can embeed in DataDescriptors.
507 {CHAR_TYPE, DOUBLE_TYPE, FLOAT_TYPE, INT_TYPE, LONG_TYPE, SHORT_TYPE,
508 UNSIGNED_INT_TYPE, UNSIGNED_LONG_TYPE, UNSIGNED_SHORT_TYPE, STRUCT_TYPE}
510 #define SIMPLE_TYPE_COUNT 9
512 /** \brief Describe a collection of data.
514 ** A description of a collection of \a type data. \a repetitions is used only
515 ** for arrays; it contains the number of elements. \a offset is used only for
516 ** struct members in host format; it contains the offset of the member from the
517 ** beginning of the struct, taking into account internal padding added by the
518 ** compiler for alignment purposes. \a members, \a length, and \a tailPadding are
519 ** used only for STRUCT_TYPE data; the \a length -long array \a members describes
520 ** the members of the nested struct, and \a tailPadding indicates how many
521 ** padding bytes the compiler adds to the end of the structure.
524 typedef struct DataDescriptorStruct {
528 /*@null@*/ struct DataDescriptorStruct *members;
532 /** DataDescriptor for an array */
533 #define SIMPLE_DATA(type,repetitions) \
534 {type, repetitions, 0, NULL, 0, 0}
535 /** DataDescriptor for an structure member */
536 #define SIMPLE_MEMBER(type,repetitions,offset) \
537 {type, repetitions, offset, NULL, 0, 0}
538 /** DataDescriptor for padding bytes */
539 #define PAD_BYTES(structType,lastMember,memberType,repetitions) \
540 sizeof(structType) - offsetof(structType, lastMember) - \
541 sizeof(memberType) * repetitions
543 XBT_PUBLIC gras_datadesc_type_t
544 gras_datadesc_import_nws(const char *name,
545 const DataDescriptor *desc,
546 unsigned long howmany);
551 #endif /* GRAS_DATADESC_H */