- \ref GRAS_tut_tour_pointers_use
- \ref GRAS_tut_tour_pointers_recap
- \ref GRAS_tut_tour_pointers_cste
-
+
<hr>
\section GRAS_tut_tour_pointers_intro Introduction to pointers in datadesc
\section GRAS_tut_tour_pointers_use Using pointers in datadesc
void declare_ddt() {
gras_datadesc_type_t ddt;
-
+
gras_datadesc_set_const("SIZE",SIZE); /* Set it before */
- gras_datadesc_by_symbol(array);
+ gras_datadesc_by_symbol(array);
}
\endverbatim
*/
- and the this example do use structures as payload,
- so we have to declare it to GRAS. Hopefully, this can be done easily by enclosing
- the structure declaration within a \ref GRAS_DEFINE_TYPE macro call. It will then copy this
- declaration into an hidden string variable, which can be automatically parsed at
+ and the this example do use structures as payload,
+ so we have to declare it to GRAS. Hopefully, this can be done easily by enclosing
+ the structure declaration within a \ref GRAS_DEFINE_TYPE macro call. It will then copy this
+ declaration into an hidden string variable, which can be automatically parsed at
run time. Of course, the declaration is also copied unmodified by this macro, so that it
- gets parsed by the compiler also.
+ gets parsed by the compiler also.
There is some semantic that GRAS cannot guess alone and you need to <i>annotate</i>
- your declaration to add some. For example, the ctn pointer can be a reference to an
- object or a whole array (in which case you also has to specify its size). This is done
+ your declaration to add some. For example, the ctn pointer can be a reference to an
+ object or a whole array (in which case you also has to specify its size). This is done
with the GRAS_ANNOTE call. It is removed from the text passed to the compiler, but it helps
- GRAS getting some information about the semantic of your data. Here, it says that \a ctn is an
- array, which size is the result of the operation \a rows * \a cols (with \a rows and \a cols
- being the other fields of the structure).
+ GRAS getting some information about the semantic of your data. Here, it says that \a ctn is an
+ array, which size is the result of the operation \a rows * \a cols (with \a rows and \a cols
+ being the other fields of the structure).
- Please note that this annotation mechanism is not as robust and cool as this example seems to
- imply. If you want to use it yourself, you'd better use the exact right syntax, which is
+ Please note that this annotation mechanism is not as robust and cool as this example seems to
+ imply. If you want to use it yourself, you'd better use the exact right syntax, which is
detailed in the \ref GRAS_dd section.
\skip GRAS_DEFINE_TYPE
#define MAX_LEAFSET COLS
GRAS_DEFINE_TYPE(gras_row_t,
-struct gras_row_t {
- int which_row;
+struct gras_row_t {
+ int which_row;
int row[COLS][MAX_ROUTESET];
};)
-
+
typedef struct gras_row_t gras_row_t;
-
-GRAS_DEFINE_TYPE(gras_welcome_msg_t,
+
+GRAS_DEFINE_TYPE(gras_welcome_msg_t,
struct gras_welcome_msg_t {
int id;
double time_sent;
-
+
int row_count;
gras_row_t *rows GRAS_ANNOTE(size,row_count);
-
+
int leaves[MAX_LEAFSET];
-};)
+};)
void declare_ddt(void) {
gras_datadesc_type_t ddt;
-
+
gras_datadesc_set_const("COLS",COLS);
gras_datadesc_set_const("MAX_ROUTESET",MAX_ROUTESET);
gras_datadesc_set_const("MAX_LEAFSET",MAX_LEAFSET);
-
+
gras_datadesc_by_symbol(gras_row_t); /* Parse it before */
ddt=gras_datadesc_ref("welcome_msg_t*",gras_datadesc_by_symbol(gras_welcome_msg_t));
- gras_msgtype_declare("welcome",ddt);
-}
+ gras_msgtype_declare("welcome",ddt);
+}
