Ya lo logré, pero faltaron apuntadores ¬¬
Busqué un poco más para completar tu ejemplo m0skit0, y encontré este de
cómo reservar arreglos multidimensionales (en inglés para el que lo quiera revisar).
En mi caso tengo esto:
En el SQL.h
Código: Seleccionar todo
struct definition {
int id;
char valueType[10];
float value;
int time;
};
int getDefinition(MYSQL *, struct histDefinition **);
En el SQL.c
Código: Seleccionar todo
int getDefinition(MYSQL *conn, struct definition **def){
MYSQL_STMT *stmt;
char *sql;
// Bind variables
MYSQL_BIND result[4];
int myId, myTime;
float myValue;
char myValueType[10];
unsigned long myValueTypeLength;
my_bool is_null[3];
my_ulonglong numRows;
int i;
sql = "select * DefinitionTable";
// Statement handler
statementHandler(&conn, &stmt, &sql);
// Initialize the result column structures
memset(result, 0, sizeof(result)); /* zero the structures */
// Init param structure
// Result
result[0].buffer_type = MYSQL_TYPE_LONG;
result[0].buffer = (void *) &myId;
result[0].is_unsigned = 0;
result[0].is_null = &is_null[0];
result[0].length = 0;
result[1].buffer_type = MYSQL_TYPE_FLOAT;
result[1].buffer = (void *) &myValue;
result[1].is_unsigned = 0;
result[1].is_null = &is_null[1];
result[1].length = 0;
result[2].buffer_type = MYSQL_TYPE_LONG;
result[2].buffer = (void *) &myTime;
result[2].is_unsigned = 0;
result[2].is_null = &is_null[2];
result[2].length = 0;
result[3].buffer_type = MYSQL_TYPE_STRING;
result[3].buffer = (void *) myValueType;
result[3].buffer_length = sizeof (myValueType);
result[3].is_null = &is_null[4];
result[3].length = &myValueTypeLength;
// Bind result
if (mysql_stmt_bind_result(stmt, result) != 0) {
print_stmt_error(stmt, "Could not bind results");
return -1;
}
// Execute!!
if (mysql_stmt_execute(stmt) != 0) {
print_stmt_error(stmt, "Could not execute statement");
return -1;
}
if (mysql_stmt_store_result(stmt) != 0) {
print_stmt_error(stmt, "Could not buffer result set");
return -1;
}
// Get the number of rows
numRows = mysql_stmt_num_rows (stmt);
// Dynamic structure
*def = (struct definition*) malloc (numRows * sizeof(struct definition));
// Fetch
for(i=0; mysql_stmt_fetch (stmt) == 0; i++){
// Init data
(*def)[i].id = 0;
(*def)[i].value = 0;
(*def)[i].time = 0;
strcpy((*def)[i].valueType,"");
(*def)[i].id = myId;
(*def)[i].deadband = myValue;
(*def)[i].deadtime = myTime;
strncpy((*def)[i].valueType, myValueType, strlen(myValueType));
(*def)[i].valueType[strlen(myValueType)] = '\0';
}
// Deallocate result set
mysql_stmt_free_result(stmt);
// Close the statement
mysql_stmt_close(stmt);
return ((int) numRows);
}
En el programa.c
Código: Seleccionar todo
int main(){
int numHistDef;
// Open database
openDB(&conn);
struct definition *def = NULL;
numDef = getDefinition(conn, &def);
syslog(LOG_INFO,"> num of Definitions: %d", numHistDef);
for (i = 0; i < numDef; i++) {
syslog(LOG_INFO, "> def[%d].id: %d", i, def[i].id);
syslog(LOG_INFO, "> def[%d].value: %f", i, def[i].value);
syslog(LOG_INFO, "> def[%d].time: %d", i, def[i].time);
syslog(LOG_INFO, "> def[%d].valueType: %s",i, def[i].valueType);
}
exit(0);
}
Salida:
Código: Seleccionar todo
Aug 19 15:14:53 buckbeak programa: > num of Definitions: 3
Aug 19 15:14:53 buckbeak programa: > def[0].id: 1
Aug 19 15:14:53 buckbeak programa: > def[0].value: 0.100000
Aug 19 15:14:53 buckbeak programa: > def[0].time: 30
Aug 19 15:14:53 buckbeak programa: > def[0].valueType: fsw
Aug 19 15:14:53 buckbeak programa: > def[1].id: 3
Aug 19 15:14:53 buckbeak programa: > def[1].value: 10.000000
Aug 19 15:14:53 buckbeak programa: > def[1].time: 30
Aug 19 15:14:53 buckbeak programa: > def[1].valueType: fsw
Aug 19 15:14:53 buckbeak programa: > def[2].id: 5
Aug 19 15:14:53 buckbeak programa: > def[2].value: 5.000000
Aug 19 15:14:53 buckbeak programa: > def[2].time: 20
Aug 19 15:14:53 buckbeak programa: > def[2].valueType: fsw
Lo bonito del conector de MySQL es que en el mismo result set viene el número de registros, haciendo solo una consulta. Justo lo que quería
PD: Te debo los typdef porque aun no soy diestro con eso
