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 (Communication facility)
21 * <center><table><tr><td><b>Top</b> <td> [\ref index]::[\ref GRAS_API]
23 * <tr><td><b>Next</b> <td> [\ref GRAS_sock]
24 * <tr><td><b>Down</b> <td> [\ref GRAS_dd_basic] </table></center>
26 * Since GRAS takes care of potential representation conversion when the platform is heterogeneous,
27 * any data which transits on the network must be described beforehand.
29 * There is several possible interfaces for this, ranging from the really completely automatic parsing to
30 * completely manual. Let's study each of them from the simplest to the more advanced:
32 * - Section \ref GRAS_dd_basic presents how to retrieve and use an already described type.
33 * - Section \ref GRAS_dd_auto shows how to get GRAS parsing your type description automagically. This
34 * is unfortunately not always possible (only works for some structures), but if it is for your data,
35 * this is definitly the way to go.
36 * - Section \ref GRAS_dd_manual presents how to build a description manually. This is useful when you want
37 * to describe an array or a pointer of pre-defined structures.
38 * - You sometimes need to exchange informations between descriptions at send or receive time. This is
39 * for example useful when your structure contains an array which size is given by another field of the
41 * - Section \ref GRAS_dd_cb_simple provides a simple interface to do so, allowing to share integers stored on a stack.
42 * - Section \ref GRAS_dd_cb_full provides a full featured interface to do so, but it may reveal somehow difficult to use.
45 /** @defgroup GRAS_dd_basic Basic operations on data descriptions
47 * <center><table><tr><td><b>Top</b> <td> [\ref index]::[\ref GRAS_API]::[\ref GRAS_dd]
49 * <tr><td><b>Next</b> <td> [\ref GRAS_dd_auto] </table></center>
51 * If you only want to send pre-existing types, simply retrieve the pre-defined description with
52 * the \ref gras_datadesc_by_name function. Existing types entail:
53 * - char (both signed and unsigned)
54 * - int (short, regular, long and long long, both signed and unsigned)
56 * - string (which is indeed a reference to a dynamically sized array of char, strlen being used to retrive the size)
58 * Example:\verbatim gras_datadesc_type_t i = gras_datadesc_by_name("int");
59 gras_datadesc_type_t uc = gras_datadesc_by_name("unsigned char");
60 gras_datadesc_type_t str = gras_datadesc_by_name("string");\endverbatim
65 /** @brief Opaque type describing a type description. */
66 typedef struct s_gras_datadesc_type *gras_datadesc_type_t;
68 /** \brief Search a type description from its name */
69 gras_datadesc_type_t gras_datadesc_by_name(const char *name);
73 /** @defgroup GRAS_dd_auto Automatic parsing of data descriptions
75 * <center><table><tr><td><b>Top</b> <td> [\ref index]::[\ref GRAS_API]::[\ref GRAS_dd]
76 * <tr><td><b>Prev</b> <td> [\ref GRAS_dd_basic]
77 * <tr><td><b>Next</b> <td> [\ref GRAS_dd_manual] </table></center>
79 * If you need to declare a new datatype, this is the simplest way to describe it to GRAS. Simply
80 * enclose its type definition into a \ref GRAS_DEFINE_TYPE macro call, and you're set. Here is
81 * an type declaration example: \verbatim GRAS_DEFINE_TYPE(mytype,struct mytype {
85 * The type is then both copied verbatim into your source file and stored for further parsing. This allows
86 * you to let GRAS parse the exact version you are actually using in your program.
87 * You can then retrieve the corresponding type description with \ref gras_datadesc_by_symbol.
88 * Don't worry too much for the performances, the type is only parsed once and a binary representation
89 * is stored and used in any subsequent calls.
91 * If your structure contains any pointer, you have to explain GRAS the size of the pointed array. This
92 * can be 1 in the case of simple references, or more in the case of regular arrays. For that, use the
93 * \ref GRAS_ANNOTE macro within the type declaration you are passing to \ref GRAS_DEFINE_TYPE. This macro
94 * rewrites itself to nothing in the declaration (so they won't pollute the type definition copied verbatim
95 * into your code), and give some information to GRAS about your pointer.
97 * GRAS_ANNOTE takes two arguments being the key name and the key value. For now, the only accepted key name
98 * is "size", to specify the length of the pointed array. It can either be:
99 * - the string "1" (without the quote),
100 * - the name of another field of the structure
101 * - a sort of computed expression for multidimensional arrays (see below -- pay attention to the warnings below).
103 * Here is an example:\verbatim GRAS_DEFINE_TYPE(s_clause,
105 struct s_array *father GRAS_ANNOTE(size,1);
107 int *data GRAS_ANNOTE(size,length);
110 int *matrix GRAS_ANNOTE(size,rows*cols);
113 * It specifies that the structure s_array contains five fields, that the \a father field is a simple reference,
114 * that the size of the array pointed by \a data is the \a length field, and that the \a matrix field is an array
115 * which size is the result of \a rows times \a cols.
117 * \warning The mecanism for multidimensional arrays is known to be fragile and cumbersome. If you want to use it,
118 * you have to understand how it is implemented: the multiplication is performed using the sizes stack. In previous example,
119 * 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
120 * added to \a cols. So, when the structure is sent, the rows field push its value onto the stack, then the \a cols field
121 * retrieve this value from the stack, compute (and push) the multiplication value. The \a matrix field can then retrive this
122 * value by poping the array. There is several ways for this to go wrong:
123 * - if the matrix field is placed before the sizes, the right value won't get pushed into the stack soon enough. Reorder your structure fields if needed.
124 * - if you write GRAS_ANNOTE(size,cols*rows); in previous example (inverting rows and cols in annotation),
125 * \a rows will be given a \ref gras_datadesc_cb_push_int_mult. This cannot work since it will try to
126 * pop the value which will be pushed by \a cols <i>afterward</i>.
127 * - if you have more than one matrix in your structure, don't interleave the size. They are pushed/poped in the structure order.
128 * - if some of the sizes are used in more than one matrix, you cannot use this mecanism -- sorry.
130 * If you cannot express your datadescs with this mechanism, you'll have to use the more advanced
131 * (and somehow complex) one described below.
133 * \warning Since GRAS_DEFINE_TYPE is a macro, you shouldn't put any comma in your type definition
134 * (comma separates macro args). For example, change \verbatim int a, b;\endverbatim to \verbatim int a;
140 /** @brief Automatically parse C code
143 #define GRAS_DEFINE_TYPE(name,def) \
144 static const char * _gras_this_type_symbol_does_not_exist__##name=#def; def
146 /** @brief Retrieve a datadesc which was previously parsed
149 #define gras_datadesc_by_symbol(name) \
150 (gras_datadesc_by_name(#name) ? \
151 gras_datadesc_by_name(#name) : \
152 gras_datadesc_parse(#name, \
153 _gras_this_type_symbol_does_not_exist__##name) \
157 * @brief Add an annotation to a type to be automatically parsed
159 #define GRAS_ANNOTE(key,val)
164 gras_datadesc_parse(const char *name, const char *C_statement);
166 /** @defgroup GRAS_dd_manual Simple manual data description
168 * <center><table><tr><td><b>Top</b> <td> [\ref index]::[\ref GRAS_API]::[\ref GRAS_dd]
169 * <tr><td><b>Prev</b> <td> [\ref GRAS_dd_auto]
170 * <tr><td><b>Next</b> <td> [\ref GRAS_dd_cb_simple] </table></center>
172 * Here are the functions to use if you want to declare your description manually.
173 * The function names should be self-explanatory in most cases.
175 * You can add callbacks to the datatypes doing any kind of action you may want. Usually,
176 * pre-send callbacks are used to prepare the type expedition while post-receive callbacks
177 * are used to fix any issue after the receive.
179 * If your types are dynamic, you'll need to add some extra callback. For example, there is a
180 * specific callback for the string type which is in charge of computing the length of the char
181 * array. This is done with the cbps mechanism, explained in next section.
183 * If your types may contain pointer cycle, you must specify it to GRAS using the @ref gras_datadesc_cycle_set.
188 unsigned long int l1;
190 unsigned long int l2;
193 my_type=gras_datadesc_struct("mystruct");
194 gras_datadesc_struct_append(my_type,"c1", gras_datadesc_by_name("unsigned char"));
195 gras_datadesc_struct_append(my_type,"l1", gras_datadesc_by_name("unsigned long"));
196 gras_datadesc_struct_append(my_type,"c2", gras_datadesc_by_name("unsigned char"));
197 gras_datadesc_struct_append(my_type,"l2", gras_datadesc_by_name("unsigned long int"));
198 gras_datadesc_struct_close(my_type);
200 my_type=gras_datadesc_ref("mystruct*", gras_datadesc_by_name("mystruct"));
202 [Use my_type to send pointers to mystruct data]\endverbatim
207 /** \brief Opaque type describing a type description callback persistant state. */
208 typedef struct s_gras_cbps *gras_cbps_t;
210 /* callbacks prototypes */
211 /** \brief Prototype of type callbacks returning nothing. */
212 typedef void (*gras_datadesc_type_cb_void_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
213 /** \brief Prototype of type callbacks returning an int. */
214 typedef int (*gras_datadesc_type_cb_int_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
215 /** \brief Prototype of type callbacks selecting a type. */
216 typedef gras_datadesc_type_t (*gras_datadesc_selector_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
219 /******************************************
220 **** Declare datadescription yourself ****
221 ******************************************/
223 gras_datadesc_type_t gras_datadesc_struct(const char *name);
224 void gras_datadesc_struct_append(gras_datadesc_type_t struct_type,
226 gras_datadesc_type_t field_type);
227 void gras_datadesc_struct_close(gras_datadesc_type_t struct_type);
230 gras_datadesc_type_t gras_datadesc_union(const char *name,
231 gras_datadesc_type_cb_int_t selector);
232 void gras_datadesc_union_append(gras_datadesc_type_t union_type,
234 gras_datadesc_type_t field_type);
235 void gras_datadesc_union_close(gras_datadesc_type_t union_type);
239 gras_datadesc_ref(const char *name,
240 gras_datadesc_type_t referenced_type);
242 gras_datadesc_ref_generic(const char *name,
243 gras_datadesc_selector_t selector);
246 gras_datadesc_array_fixed(const char *name,
247 gras_datadesc_type_t element_type,
248 long int fixed_size);
250 gras_datadesc_array_dyn(const char *name,
251 gras_datadesc_type_t element_type,
252 gras_datadesc_type_cb_int_t dynamic_size);
254 gras_datadesc_ref_pop_arr(gras_datadesc_type_t element_type);
257 gras_datadesc_dynar(gras_datadesc_type_t elm_t,
258 void_f_pvoid_t *free_func);
260 /*********************************
261 * Change stuff within datadescs *
262 *********************************/
264 /** \brief Specify that this type may contain cycles */
265 void gras_datadesc_cycle_set(gras_datadesc_type_t type);
266 /** \brief Specify that this type do not contain any cycles (default) */
267 void gras_datadesc_cycle_unset(gras_datadesc_type_t type);
268 /** \brief Add a pre-send callback to this datadesc. */
269 void gras_datadesc_cb_send (gras_datadesc_type_t type,
270 gras_datadesc_type_cb_void_t pre);
271 /** \brief Add a post-receive callback to this datadesc.*/
272 void gras_datadesc_cb_recv(gras_datadesc_type_t type,
273 gras_datadesc_type_cb_void_t post);
274 /** \brief Add a pre-send callback to the given field of the datadesc */
275 void gras_datadesc_cb_field_send (gras_datadesc_type_t type,
276 const char *field_name,
277 gras_datadesc_type_cb_void_t pre);
278 /** \brief Add a post-receive callback to the given field of the datadesc */
279 void gras_datadesc_cb_field_recv(gras_datadesc_type_t type,
280 const char *field_name,
281 gras_datadesc_type_cb_void_t post);
282 /** \brief Add a pre-send callback to the given field resulting in its value to be pushed */
283 void gras_datadesc_cb_field_push (gras_datadesc_type_t type,
284 const char *field_name);
285 /** \brief Add a pre-send callback to the given field resulting in its value multiplied to any previously pushed value and then pushed back */
286 void gras_datadesc_cb_field_push_multiplier (gras_datadesc_type_t type,
287 const char *field_name);
289 /******************************
290 * Get stuff within datadescs *
291 ******************************/
292 /** \brief Returns the name of a datadescription */
293 const char * gras_datadesc_get_name(gras_datadesc_type_t ddt);
294 /** \brief Returns the identifier of a datadescription */
295 int gras_datadesc_get_id(gras_datadesc_type_t ddt);
299 /** @defgroup GRAS_dd_cb_simple Data description with Callback Persistant State: Simple push/pop mechanism
301 * <center><table><tr><td><b>Top</b> <td> [\ref index]::[\ref GRAS_API]::[\ref GRAS_dd]
302 * <tr><td><b>Prev</b> <td> [\ref GRAS_dd_manual]
303 * <tr><td><b>Next</b> <td> [\ref GRAS_dd_cb_full] </table></center>
305 * Sometimes, one of the callbacks need to leave information for the next ones. If this is a simple integer (such as
306 * an array size), you can use the functions described here. If not, you'll have to play with the complete cbps interface.
309 * Here is an example:\verbatim
315 my_type=gras_datadesc_struct("s_array");
316 gras_datadesc_struct_append(my_type,"length", gras_datadesc_by_name("int"));
317 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int);
319 gras_datadesc_struct_append(my_type,"data",
320 gras_datadesc_array_dyn ("s_array::data",gras_datadesc_by_name("int"), gras_datadesc_cb_pop));
321 gras_datadesc_struct_close(my_type);
325 * The *_mult versions are intended for multi-dimensional arrays: They multiply their value to the previously pushed one
326 * (by another field callback) and push the result of the multiplication back. An example of use follows. Please note
327 * that the first field needs a regular push callback, not a multiplier one. Think of it as a stacked calculator (man dc(1)).\verbatim
334 my_type=gras_datadesc_struct("s_matrix");
335 gras_datadesc_struct_append(my_type,"row", gras_datadesc_by_name("int"));
336 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int);
337 gras_datadesc_struct_append(my_type,"col", gras_datadesc_by_name("int"));
338 gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int_mult);
340 gras_datadesc_struct_append(my_type,"data",
341 gras_datadesc_array_dyn ("s_matrix::data",gras_datadesc_by_name("int"), gras_datadesc_cb_pop));
342 gras_datadesc_struct_close(my_type);
349 gras_cbps_i_push(gras_cbps_t ps, int val);
351 gras_cbps_i_pop(gras_cbps_t ps);
353 int gras_datadesc_cb_pop(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
355 void gras_datadesc_cb_push_int(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
356 void gras_datadesc_cb_push_uint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
357 void gras_datadesc_cb_push_lint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
358 void gras_datadesc_cb_push_ulint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
360 void gras_datadesc_cb_push_int_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
361 void gras_datadesc_cb_push_uint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
362 void gras_datadesc_cb_push_lint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
363 void gras_datadesc_cb_push_ulint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
368 /** @defgroup GRAS_dd_cb_full Data description with Callback Persistant State: Full featured interface
370 * <center><table><tr><td><b>Top</b> <td> [\ref index]::[\ref GRAS_API]::[\ref GRAS_dd]
371 * <tr><td><b>Prev</b> <td> [\ref GRAS_dd_cb_simple]
372 * <tr><td>Next <td> </table></center>
374 * Sometimes, one of the callbacks need to leave information for the next ones. If the simple push/pop mechanism
375 * introduced in previous section isn't enough, you can always use this full featured one.
380 void gras_cbps_v_pop (gras_cbps_t ps,
382 /* OUT */ gras_datadesc_type_t *ddt,
383 /* OUT */ void **res);
384 void gras_cbps_v_push(gras_cbps_t ps,
387 gras_datadesc_type_t ddt);
388 void gras_cbps_v_set (gras_cbps_t ps,
391 gras_datadesc_type_t ddt);
393 void * gras_cbps_v_get (gras_cbps_t ps,
395 /* OUT */ gras_datadesc_type_t *ddt);
397 void gras_cbps_block_begin(gras_cbps_t ps);
398 void gras_cbps_block_end(gras_cbps_t ps);
404 /*******************************
405 **** About data convertion ****
406 *******************************/
407 int gras_arch_selfid(void); /* ID of this arch */
410 /*****************************
411 **** NWS datadescription * FIXME: obsolete?
412 *****************************/
415 * Basic types we can embeed in DataDescriptors.
418 {CHAR_TYPE, DOUBLE_TYPE, FLOAT_TYPE, INT_TYPE, LONG_TYPE, SHORT_TYPE,
419 UNSIGNED_INT_TYPE, UNSIGNED_LONG_TYPE, UNSIGNED_SHORT_TYPE, STRUCT_TYPE}
421 #define SIMPLE_TYPE_COUNT 9
423 /** \brief Describe a collection of data.
425 ** A description of a collection of \a type data. \a repetitions is used only
426 ** for arrays; it contains the number of elements. \a offset is used only for
427 ** struct members in host format; it contains the offset of the member from the
428 ** beginning of the struct, taking into account internal padding added by the
429 ** compiler for alignment purposes. \a members, \a length, and \a tailPadding are
430 ** used only for STRUCT_TYPE data; the \a length -long array \a members describes
431 ** the members of the nested struct, and \a tailPadding indicates how many
432 ** padding bytes the compiler adds to the end of the structure.
435 typedef struct DataDescriptorStruct {
439 /*@null@*/ struct DataDescriptorStruct *members;
443 /** DataDescriptor for an array */
444 #define SIMPLE_DATA(type,repetitions) \
445 {type, repetitions, 0, NULL, 0, 0}
446 /** DataDescriptor for an structure member */
447 #define SIMPLE_MEMBER(type,repetitions,offset) \
448 {type, repetitions, offset, NULL, 0, 0}
449 /** DataDescriptor for padding bytes */
450 #define PAD_BYTES(structType,lastMember,memberType,repetitions) \
451 sizeof(structType) - offsetof(structType, lastMember) - \
452 sizeof(memberType) * repetitions
455 gras_datadesc_import_nws(const char *name,
456 const DataDescriptor *desc,
457 unsigned long howmany);
462 #endif /* GRAS_DATADESC_H */