/* $Id$ */
/* gras/datadesc.h - Describing the data you want to exchange */
/* Copyright (c) 2003, 2004 Martin Quinson. All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
#ifndef GRAS_DATADESC_H
#define GRAS_DATADESC_H
#include "xbt/misc.h" /* SG_BEGIN_DECL */
#include "xbt/dynar.h" /* void_f_pvoid_t */
SG_BEGIN_DECL()
/** @addtogroup GRAS_dd Data description
* @brief Describing data to be exchanged
*
* Since GRAS takes care of potential representation conversion when the platform is heterogeneous,
* any data which transits on the network must be described beforehand.
*
* There is several possible interfaces for this, ranging from the really completely automatic parsing to
* completely manual. Let's study each of them from the simplest to the more advanced:
*
* - Section \ref GRAS_dd_basic presents how to retrieve and use an already described type.
* - Section \ref GRAS_dd_auto shows how to get GRAS parsing your type description automagically. This
* is unfortunately not always possible (only works for some structures), but if it is for your data,
* this is definitly the way to go.
* - Section \ref GRAS_dd_manual presents how to build a description manually. This is useful when you want
* to describe an array or a pointer of pre-defined structures.
* - You sometimes need to exchange informations between descriptions at send or receive time. This is
* for example useful when your structure contains an array which size is given by another field of the
* structure.
* - Section \ref GRAS_dd_cb_simple provides a simple interface to do so, allowing to share integers stored on a stack.
* - Section \ref GRAS_dd_cb_full provides a full featured interface to do so, but it may reveal somehow difficult to use.
**/
/** @defgroup GRAS_dd_basic Basic operations on data descriptions
* @ingroup GRAS_dd
* \htmlonly \endhtmlonly
*
* If you only want to send pre-existing types, simply retrieve the pre-defined description with
* the \ref gras_datadesc_by_name function. Existing types entail:
* - char (both signed and unsigned)
* - int (short, regular, long and long long, both signed and unsigned)
* - float and double
* - string (which is indeed a reference to a dynamically sized array of char, strlen being used to retrive the size)
*
* Example:\verbatim gras_datadesc_type_t i = gras_datadesc_by_name("int");
gras_datadesc_type_t uc = gras_datadesc_by_name("unsigned char");
gras_datadesc_type_t str = gras_datadesc_by_name("string");\endverbatim
*
*/
/* @{ */
/** @brief Opaque type describing a type description. */
typedef struct s_gras_datadesc_type *gras_datadesc_type_t;
/** \brief Search a type description from its name */
gras_datadesc_type_t gras_datadesc_by_name(const char *name);
/* @} */
/** @defgroup GRAS_dd_auto Automatic parsing of data descriptions
* @ingroup GRAS_dd
* \htmlonly \endhtmlonly
*
* If you need to declare a new datatype, this is the simplest way to describe it to GRAS. Simply
* enclose its type definition into a \ref GRAS_DEFINE_TYPE macro call, and you're set. Here is
* an type declaration example: \verbatim GRAS_DEFINE_TYPE(mytype,struct mytype {
int myfirstfield;
char mysecondfield;
});\endverbatim
* The type is then both copied verbatim into your source file and stored for further parsing. This allows
* you to let GRAS parse the exact version you are actually using in your program.
* You can then retrieve the corresponding type description with \ref gras_datadesc_by_symbol.
* Don't worry too much for the performances, the type is only parsed once and a binary representation
* is stored and used in any subsequent calls.
*
* If your structure contains any pointer, you have to explain GRAS the size of the pointed array. This
* can be 1 in the case of simple references, or more in the case of regular arrays. For that, use the
* \ref GRAS_ANNOTE macro within the type declaration you are passing to \ref GRAS_DEFINE_TYPE. This macro
* rewrites itself to nothing in the declaration (so they won't pollute the type definition copied verbatim
* into your code), and give some information to GRAS about your pointer.
* GRAS_ANNOTE takes two arguments being the key name and the key value. For now, the only accepted key name
* is "size", to specify the length of the pointed array. It can either be:
* - the string "1" (without the quote),
* - the name of another field of the structure
* - a sort of computed expression for multidimensional arrays (see below -- pay attention to the warnings below).
*
* Here is an example:\verbatim GRAS_DEFINE_TYPE(s_clause,
struct s_array {
struct s_array *father GRAS_ANNOTE(size,1);
int length;
int *data GRAS_ANNOTE(size,length);
int rows;
int cols;
int *matrix GRAS_ANNOTE(size,rows*cols);
}
;)\endverbatim
* It specifies that the structure s_array contains five fields, that the \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 \a matrix field is an array
* which size is the result of \a rows times \a cols.
*
* \warning Since GRAS_DEFINE_TYPE is a macro, you shouldn't put any comma in your type definition
* (comma separates macro args). For example, change \verbatim int a, b;\endverbatim to \verbatim int a;
int b;\endverbatim
*
*
Defining multidimentional arrays
*
* The mecanism for multidimensional arrays is known to be fragile and cumbersome. If you want to use it,
* you have to understand how it is implemented: the multiplication is performed using the sizes stack. In previous example,
* 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
* 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
* retrieve this value from the stack, compute (and push) the multiplication value. The \a matrix field can then retrive this
* value by poping the array. There is several ways for this to go wrong:
* - 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.
* - if you write GRAS_ANNOTE(size,cols*rows); in previous example (inverting rows and cols in annotation),
* \a rows will be given a \ref gras_datadesc_cb_push_int_mult. This cannot work since it will try to
* pop the value which will be pushed by \a cols afterward.
* - if you have more than one matrix in your structure, don't interleave the size. They are pushed/poped in the structure order.
* - if some of the sizes are used in more than one matrix, you cannot use this mecanism -- sorry.
*
* If you cannot express your datadescs with this mechanism, you'll have to use the more advanced
* (and somehow complex) one described in the \ref GRAS_dd_cb_full.
*
* Projects spanning over multiple files
*
* GRAS_DEFINE_TYPE declares some symbols to work, it needs some special
* care when used in several files. In such case, you want the regular type
* definition in all files, but the gras specific symbol defined in only
* one file. For example, consider the following gras project sketch.
*
\verbatim #include
GRAS_DEFINE_TYPE(my_type,struct my_type {
int a;
int b;
double c;
});
int client(int argc, char *argv[]) {
...
}
int server(int argc, char *argv[]) {
...
}\endverbatim
*
* If you want to split this in two files (one for each kind of processes),
* you need to put the GRAS_DEFINE_TYPE block in a separate header. But
* then you cannot include this right away in all files because the extra
* symbols would be defined in dupplicate.
*
* You thus have to decide in which file the symbols will live. In that
* file, include the header without restriction:
*
\verbatim #include "my_header.h"
int client(int argc, char *argv[]) {
...
}\endverbatim
* And in the other files needing the C definitions without the extra GRAS
* symbols, declare the symbol GRAS_DEFINE_TYPE_EXTERN before:
*
\verbatim #define GRAS_DEFINE_TYPE_EXTERN
#include "my_header.h"
int server(int argc, char *argv[]) {
...
}\endverbatim
*
*/
/** @{ */
/** @brief Automatically parse C code
* @hideinitializer
*/
#define GRAS_DEFINE_TYPE(name,def) \
const char * _gras_this_type_symbol_does_not_exist__##name=#def; def
#ifndef DOXYGEN_SKIP /* doxygen don't like macro fun too much */
# ifdef GRAS_DEFINE_TYPE_EXTERN
# undef GRAS_DEFINE_TYPE
# define GRAS_DEFINE_TYPE(name,def) def
# undef GRAS_DEFINE_TYPE_EXTERN
# endif
#endif
/** @brief if this symbol is defined, the \a GRAS_DEFINE_TYPE symbols live in another file.
* @hideinitializer
*/
#define GRAS_DEFINE_TYPE_EXTERN 1
/** @brief Retrieve a datadesc which was previously parsed
* @hideinitializer
*/
#define gras_datadesc_by_symbol(name) \
(gras_datadesc_by_name(#name) ? \
gras_datadesc_by_name(#name) : \
gras_datadesc_parse(#name, \
_gras_this_type_symbol_does_not_exist__##name) \
)
/** @def GRAS_ANNOTE
* @brief Add an annotation to a type to be automatically parsed
*/
#define GRAS_ANNOTE(key,val)
/* @} */
gras_datadesc_type_t
gras_datadesc_parse(const char *name, const char *C_statement);
/** @defgroup GRAS_dd_manual Simple manual data description
* @ingroup GRAS_dd
*
* Here are the functions to use if you want to declare your description manually.
* The function names should be self-explanatory in most cases.
*
* You can add callbacks to the datatypes doing any kind of action you may want. Usually,
* pre-send callbacks are used to prepare the type expedition while post-receive callbacks
* are used to fix any issue after the receive.
*
* If your types are dynamic, you'll need to add some extra callback. For example, there is a
* specific callback for the string type which is in charge of computing the length of the char
* array. This is done with the cbps mechanism, explained in next section.
*
* If your types may contain pointer cycle, you must specify it to GRAS using the @ref gras_datadesc_cycle_set.
*
* Example:\verbatim
typedef struct {
unsigned char c1;
unsigned long int l1;
unsigned char c2;
unsigned long int l2;
} mystruct;
[...]
my_type=gras_datadesc_struct("mystruct");
gras_datadesc_struct_append(my_type,"c1", gras_datadesc_by_name("unsigned char"));
gras_datadesc_struct_append(my_type,"l1", gras_datadesc_by_name("unsigned long"));
gras_datadesc_struct_append(my_type,"c2", gras_datadesc_by_name("unsigned char"));
gras_datadesc_struct_append(my_type,"l2", gras_datadesc_by_name("unsigned long int"));
gras_datadesc_struct_close(my_type);
my_type=gras_datadesc_ref("mystruct*", gras_datadesc_by_name("mystruct"));
[Use my_type to send pointers to mystruct data]\endverbatim
*/
/* @{ */
/** \brief Opaque type describing a type description callback persistant state. */
typedef struct s_gras_cbps *gras_cbps_t;
/* callbacks prototypes */
/** \brief Prototype of type callbacks returning nothing. */
typedef void (*gras_datadesc_type_cb_void_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
/** \brief Prototype of type callbacks returning an int. */
typedef int (*gras_datadesc_type_cb_int_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
/** \brief Prototype of type callbacks selecting a type. */
typedef gras_datadesc_type_t (*gras_datadesc_selector_t)(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
/******************************************
**** Declare datadescription yourself ****
******************************************/
gras_datadesc_type_t gras_datadesc_struct(const char *name);
void gras_datadesc_struct_append(gras_datadesc_type_t struct_type,
const char *name,
gras_datadesc_type_t field_type);
void gras_datadesc_struct_close(gras_datadesc_type_t struct_type);
gras_datadesc_type_t gras_datadesc_union(const char *name,
gras_datadesc_type_cb_int_t selector);
void gras_datadesc_union_append(gras_datadesc_type_t union_type,
const char *name,
gras_datadesc_type_t field_type);
void gras_datadesc_union_close(gras_datadesc_type_t union_type);
gras_datadesc_type_t
gras_datadesc_ref(const char *name,
gras_datadesc_type_t referenced_type);
gras_datadesc_type_t
gras_datadesc_ref_generic(const char *name,
gras_datadesc_selector_t selector);
gras_datadesc_type_t
gras_datadesc_array_fixed(const char *name,
gras_datadesc_type_t element_type,
long int fixed_size);
gras_datadesc_type_t
gras_datadesc_array_dyn(const char *name,
gras_datadesc_type_t element_type,
gras_datadesc_type_cb_int_t dynamic_size);
gras_datadesc_type_t
gras_datadesc_ref_pop_arr(gras_datadesc_type_t element_type);
gras_datadesc_type_t
gras_datadesc_dynar(gras_datadesc_type_t elm_t,
void_f_pvoid_t *free_func);
/*********************************
* Change stuff within datadescs *
*********************************/
/** \brief Specify that this type may contain cycles */
void gras_datadesc_cycle_set(gras_datadesc_type_t type);
/** \brief Specify that this type do not contain any cycles (default) */
void gras_datadesc_cycle_unset(gras_datadesc_type_t type);
/** \brief Add a pre-send callback to this datadesc. */
void gras_datadesc_cb_send (gras_datadesc_type_t type,
gras_datadesc_type_cb_void_t pre);
/** \brief Add a post-receive callback to this datadesc.*/
void gras_datadesc_cb_recv(gras_datadesc_type_t type,
gras_datadesc_type_cb_void_t post);
/** \brief Add a pre-send callback to the given field of the datadesc */
void gras_datadesc_cb_field_send (gras_datadesc_type_t type,
const char *field_name,
gras_datadesc_type_cb_void_t pre);
/** \brief Add a post-receive callback to the given field of the datadesc */
void gras_datadesc_cb_field_recv(gras_datadesc_type_t type,
const char *field_name,
gras_datadesc_type_cb_void_t post);
/** \brief Add a pre-send callback to the given field resulting in its value to be pushed */
void gras_datadesc_cb_field_push (gras_datadesc_type_t type,
const char *field_name);
/** \brief Add a pre-send callback to the given field resulting in its value multiplied to any previously pushed value and then pushed back */
void gras_datadesc_cb_field_push_multiplier (gras_datadesc_type_t type,
const char *field_name);
/******************************
* Get stuff within datadescs *
******************************/
/** \brief Returns the name of a datadescription */
const char * gras_datadesc_get_name(gras_datadesc_type_t ddt);
/** \brief Returns the identifier of a datadescription */
int gras_datadesc_get_id(gras_datadesc_type_t ddt);
/* @} */
/** @defgroup GRAS_dd_cb_simple Data description with Callback Persistant State: Simple push/pop mechanism
* @ingroup GRAS_dd
*
* Sometimes, one of the callbacks need to leave information for the next ones. If this is a simple integer (such as
* an array size), you can use the functions described here. If not, you'll have to play with the complete cbps interface.
*
* \htmlonly \endhtmlonly
*
* Here is an example:\verbatim
struct s_array {
int length;
int *data;
}
[...]
my_type=gras_datadesc_struct("s_array");
gras_datadesc_struct_append(my_type,"length", gras_datadesc_by_name("int"));
gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int);
gras_datadesc_struct_append(my_type,"data",
gras_datadesc_array_dyn ("s_array::data",gras_datadesc_by_name("int"), gras_datadesc_cb_pop));
gras_datadesc_struct_close(my_type);
\endverbatim
*
* The *_mult versions are intended for multi-dimensional arrays: They multiply their value to the previously pushed one
* (by another field callback) and push the result of the multiplication back. An example of use follows. Please note
* that the first field needs a regular push callback, not a multiplier one. Think of it as a stacked calculator (man dc(1)).\verbatim
struct s_matrix {
int row;
int col;
int *data;
}
[...]
my_type=gras_datadesc_struct("s_matrix");
gras_datadesc_struct_append(my_type,"row", gras_datadesc_by_name("int"));
gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int);
gras_datadesc_struct_append(my_type,"col", gras_datadesc_by_name("int"));
gras_datadesc_cb_field_send (my_type, "length", gras_datadesc_cb_push_int_mult);
gras_datadesc_struct_append(my_type,"data",
gras_datadesc_array_dyn ("s_matrix::data",gras_datadesc_by_name("int"), gras_datadesc_cb_pop));
gras_datadesc_struct_close(my_type);
\endverbatim
*/
/* @{ */
void
gras_cbps_i_push(gras_cbps_t ps, int val);
int
gras_cbps_i_pop(gras_cbps_t ps);
int gras_datadesc_cb_pop(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
void gras_datadesc_cb_push_int(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
void gras_datadesc_cb_push_uint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
void gras_datadesc_cb_push_lint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
void gras_datadesc_cb_push_ulint(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
void gras_datadesc_cb_push_int_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
void gras_datadesc_cb_push_uint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
void gras_datadesc_cb_push_lint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
void gras_datadesc_cb_push_ulint_mult(gras_datadesc_type_t typedesc, gras_cbps_t vars, void *data);
/* @} */
/** @defgroup GRAS_dd_cb_full Data description with Callback Persistant State: Full featured interface
* @ingroup GRAS_dd
*
* Sometimes, one of the callbacks need to leave information for the next
* ones. If the simple push/pop mechanism introduced in previous section
* isn't enough, you can always use this full featured one. The bad point is
* that it is quite badly documented...
*
* \htmlonly \endhtmlonly
*
*/
/* @{ */
void gras_cbps_v_pop (gras_cbps_t ps,
const char *name,
/* OUT */ gras_datadesc_type_t *ddt,
/* OUT */ void **res);
void gras_cbps_v_push(gras_cbps_t ps,
const char *name,
void *data,
gras_datadesc_type_t ddt);
void gras_cbps_v_set (gras_cbps_t ps,
const char *name,
void *data,
gras_datadesc_type_t ddt);
void * gras_cbps_v_get (gras_cbps_t ps,
const char *name,
/* OUT */ gras_datadesc_type_t *ddt);
void gras_cbps_block_begin(gras_cbps_t ps);
void gras_cbps_block_end(gras_cbps_t ps);
/* @} */
/* @} */
/*******************************
**** About data convertion ****
*******************************/
int gras_arch_selfid(void); /* ID of this arch */
/*****************************
**** NWS datadescription * FIXME: obsolete?
*****************************/
/**
* Basic types we can embeed in DataDescriptors.
*/
typedef enum
{CHAR_TYPE, DOUBLE_TYPE, FLOAT_TYPE, INT_TYPE, LONG_TYPE, SHORT_TYPE,
UNSIGNED_INT_TYPE, UNSIGNED_LONG_TYPE, UNSIGNED_SHORT_TYPE, STRUCT_TYPE}
DataTypes;
#define SIMPLE_TYPE_COUNT 9
/** \brief Describe a collection of data.
*
** A description of a collection of \a type data. \a repetitions is used only
** for arrays; it contains the number of elements. \a offset is used only for
** struct members in host format; it contains the offset of the member from the
** beginning of the struct, taking into account internal padding added by the
** compiler for alignment purposes. \a members, \a length, and \a tailPadding are
** used only for STRUCT_TYPE data; the \a length -long array \a members describes
** the members of the nested struct, and \a tailPadding indicates how many
** padding bytes the compiler adds to the end of the structure.
*/
typedef struct DataDescriptorStruct {
DataTypes type;
size_t repetitions;
size_t offset;
/*@null@*/ struct DataDescriptorStruct *members;
size_t length;
size_t tailPadding;
} DataDescriptor;
/** DataDescriptor for an array */
#define SIMPLE_DATA(type,repetitions) \
{type, repetitions, 0, NULL, 0, 0}
/** DataDescriptor for an structure member */
#define SIMPLE_MEMBER(type,repetitions,offset) \
{type, repetitions, offset, NULL, 0, 0}
/** DataDescriptor for padding bytes */
#define PAD_BYTES(structType,lastMember,memberType,repetitions) \
sizeof(structType) - offsetof(structType, lastMember) - \
sizeof(memberType) * repetitions
gras_datadesc_type_t
gras_datadesc_import_nws(const char *name,
const DataDescriptor *desc,
unsigned long howmany);
SG_END_DECL()
#endif /* GRAS_DATADESC_H */