src/gmxlib/selection/selelem.h

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  31 /*! \internal \file
  32  * \brief Definition of \c t_selelem and related things.
  33  *
  34  * The selection element trees constructed by the parser and the compiler
  35  * are described on the respective pages:
  36  * \ref selparser and \ref selcompiler.
  37  *
  38  * This is an implementation header: there should be no need to use it outside
  39  * this directory.
  40  */
  41 #ifndef SELECTION_ELEMENT_H
  42 #define SELECTION_ELEMENT_H
  43
  44 #include <types/simple.h>
  45
  46 #include <indexutil.h>
  47 #include <selvalue.h>
  48
  49 struct gmx_ana_poscalc_t;
  50 struct gmx_ana_selparam_t;
  51 struct gmx_ana_selmethod_t;
  52
  53 struct gmx_sel_evaluate_t;
  54 struct gmx_sel_mempool_t;
  55 struct t_selelem;
  56
  57 /********************************************************************/
  58 /*! \name Enumerations for expression types
  59  ********************************************************************/
  60 /*@{*/
  61
  62 /** Defines the type of a \c t_selelem object. */
  63 typedef enum
  64 {
  65     /** Constant-valued expression. */
  66     SEL_CONST,
  67     /** Method expression that requires evaluation. */
  68     SEL_EXPRESSION,
  69     /** Boolean expression. */
  70     SEL_BOOLEAN,
  71     /** Arithmetic expression. */
  72     SEL_ARITHMETIC,
  73     /** Root node of the evaluation tree. */
  74     SEL_ROOT,
  75     /** Subexpression that may be referenced several times. */
  76     SEL_SUBEXPR,
  77     /** Reference to a subexpression. */
  78     SEL_SUBEXPRREF,
  79     /** Post-processing of selection value. */
  80     SEL_MODIFIER
  81 } e_selelem_t;
  82
  83 /** Defines the boolean operation of \c t_selelem objects with type \ref SEL_BOOLEAN. */
  84 typedef enum
  85 {
  86     BOOL_NOT,           /**< Not */
  87     BOOL_AND,           /**< And */
  88     BOOL_OR,            /**< Or */
  89     BOOL_XOR            /**< Xor (not implemented). */
  90 } e_boolean_t;
  91
  92 /** Defines the arithmetic operation of \c t_selelem objects with type \ref SEL_ARITHMETIC. */
  93 typedef enum
  94 {
  95     ARITH_PLUS,         /**< + */
  96     ARITH_MINUS,        /**< - */
  97     ARITH_NEG,          /**< Unary - */
  98     ARITH_MULT,         /**< * */
  99     ARITH_DIV,          /**< / */
 100     ARITH_EXP,          /**< ^ (to power) */
 101 } e_arithmetic_t;
 102
 103 /** Returns a string representation of the type of a \c t_selelem. */
 104 extern const char *
 105 _gmx_selelem_type_str(struct t_selelem *sel);
 106 /** Returns a string representation of the boolean type of a \ref SEL_BOOLEAN \c t_selelem. */
 107 extern const char *
 108 _gmx_selelem_boolean_type_str(struct t_selelem *sel);
 109 /** Returns a string representation of the type of a \c gmx_ana_selvalue_t. */
 110 extern const char *
 111 _gmx_sel_value_type_str(gmx_ana_selvalue_t *val);
 112
 113 /*@}*/
 114
 115
 116 /********************************************************************/
 117 /*! \name Selection expression flags
 118  * \anchor selelem_flags
 119  ********************************************************************/
 120 /*@{*/
 121 /*! \brief
 122  * Selection value flags are set.
 123  *
 124  * If this flag is set, the flags covered by \ref SEL_VALFLAGMASK
 125  * have been set properly for the element.
 126  */
 127 #define SEL_FLAGSSET    1
 128 /*! \brief
 129  * The element evaluates to a single value.
 130  *
 131  * This flag is always set for \ref GROUP_VALUE elements.
 132  */
 133 #define SEL_SINGLEVAL   2
 134 /*! \brief
 135  * The element evaluates to one value for each input atom.
 136  */
 137 #define SEL_ATOMVAL     4
 138 /*! \brief
 139  * The element evaluates to an arbitrary number of values.
 140  */
 141 #define SEL_VARNUMVAL   8
 142 /*! \brief
 143  * The element (or one of its children) is dynamic.
 144  */
 145 #define SEL_DYNAMIC     16
 146 /*! \brief
 147  * Mask that covers the flags that describe the number of values.
 148  */
 149 #define SEL_VALTYPEMASK (SEL_SINGLEVAL | SEL_ATOMVAL | SEL_VARNUMVAL)
 150 /*! \brief
 151  * Mask that covers the flags that describe the value type.
 152  */
 153 #define SEL_VALFLAGMASK (SEL_FLAGSSET | SEL_VALTYPEMASK | SEL_DYNAMIC)
 154 /*! \brief
 155  * Data has been allocated for the \p v.u union.
 156  *
 157  * If not set, the \p v.u.ptr points to data allocated externally.
 158  * This is the case if the value of the element is used as a parameter
 159  * for a selection method or if the element evaluates the final value of
 160  * a selection.
 161  *
 162  * Even if the flag is set, \p v.u.ptr can be NULL during initialization.
 163  *
 164  * \todo
 165  * This flag overlaps with the function of \p v.nalloc field, and could
 166  * probably be removed, making memory management simpler. Currently, the
 167  * \p v.nalloc field is not kept up-to-date in all cases when this flag
 168  * is changed and is used in places where this flag is not, so this would
 169  * require a careful investigation of the selection code.
 170  */
 171 #define SEL_ALLOCVAL    (1<<8)
 172 /*! \brief
 173  * Data has been allocated for the group/position structure.
 174  *
 175  * If not set, the memory allocated for fields in \p v.u.g or \p v.u.p is
 176  * managed externally.
 177  *
 178  * This field has no effect if the value type is not \ref GROUP_VALUE or
 179  * \ref POS_VALUE, but should not be set.
 180  */
 181 #define SEL_ALLOCDATA   (1<<9)
 182 /*! \brief
 183  * \p method->init_frame should be called for the frame.
 184  */
 185 #define SEL_INITFRAME   (1<<10)
 186 /*! \brief
 187  * Parameter has been evaluated for the current frame.
 188  *
 189  * This flag is set for children of \ref SEL_EXPRESSION elements (which
 190  * describe method parameters) after the element has been evaluated for the
 191  * current frame.
 192  * It is not set for \ref SEL_ATOMVAL elements, because they may need to
 193  * be evaluated multiple times.
 194  */
 195 #define SEL_EVALFRAME   (1<<11)
 196 /*! \brief
 197  * \p method->init has been called.
 198  */
 199 #define SEL_METHODINIT  (1<<12)
 200 /*! \brief
 201  * \p method->outinit has been called.
 202  *
 203  * This flag is also used for \ref SEL_SUBEXPRREF elements.
 204  */
 205 #define SEL_OUTINIT     (1<<13)
 206 /*@}*/
 207
 208
 209 /********************************************************************/
 210 /*! \name Selection expression data structures and functions
 211  ********************************************************************/
 212 /*@{*/
 213
 214 struct t_selelem;
 215
 216 /*! \brief
 217  * Function pointer for evaluating a \c t_selelem.
 218  */
 219 typedef int (*sel_evalfunc)(struct gmx_sel_evaluate_t *data,
 220                             struct t_selelem *sel, gmx_ana_index_t *g);
 221
 222 /*! \internal \brief
 223  * Represents an element of a selection expression.
 224  */
 225 typedef struct t_selelem
 226 {
 227     /*! \brief Name of the element.
 228      *
 229      * This field is only used for informative purposes.
 230      * It is always either NULL or a pointer to a string.
 231      * Memory is never allocated for it directly.
 232      */
 233     const char                         *name;
 234     /** Type of the element. */
 235     e_selelem_t                         type;
 236     /*! \brief
 237      * Value storage of the element.
 238      *
 239      * This field contains the evaluated value of the element, as well as
 240      * the output value type.
 241      */
 242     gmx_ana_selvalue_t                  v;
 243     /*! \brief
 244      * Evaluation function for the element.
 245      *
 246      * Can be either NULL (if the expression is a constant and does not require
 247      * evaluation) or point to one of the functions defined in evaluate.h.
 248      */
 249     sel_evalfunc                        evaluate;
 250     /*! \brief
 251      * Information flags about the element.
 252      *
 253      * Allowed flags are listed here:
 254      * \ref selelem_flags "flags for \c t_selelem".
 255      */
 256     int                                 flags;
 257     /** Data required by the evaluation function. */
 258     union {
 259         /*! \brief Index group data for several element types.
 260          *
 261          *  - \ref SEL_CONST : if the value type is \ref GROUP_VALUE,
 262          *    this field holds the unprocessed group value.
 263          *  - \ref SEL_ROOT : holds the group value for which the
 264          *    selection subtree should be evaluated.
 265          *  - \ref SEL_SUBEXPR : holds the group for which the subexpression
 266          *    has been evaluated.
 267          */
 268         gmx_ana_index_t                 cgrp;
 269         /** Data for \ref SEL_EXPRESSION and \ref SEL_MODIFIER elements. */
 270         struct {
 271             /** Pointer the the method used in this expression. */
 272             struct gmx_ana_selmethod_t *method;
 273             /** Pointer to the data allocated by the method's \p init_data (see sel_datafunc()). */
 274             void                       *mdata;
 275             /** Pointer to the position data passed to the method. */
 276             struct gmx_ana_pos_t       *pos;
 277             /** Pointer to the evaluation data for \p pos. */
 278             struct gmx_ana_poscalc_t   *pc;
 279         }                               expr;
 280         /** Operation type for \ref SEL_BOOLEAN elements. */
 281         e_boolean_t                     boolt;
 282         /** Operation type for \ref SEL_ARITHMETIC elements. */
 283         struct {
 284             /** Operation type. */
 285             e_arithmetic_t              type;
 286             /** String representation. */
 287             char                       *opstr;
 288         }                               arith;
 289         /** Associated selection parameter for \ref SEL_SUBEXPRREF elements. */
 290         struct gmx_ana_selparam_t      *param;
 291     }                                   u;
 292     /** Memory pool to use for values, or NULL if standard memory handling. */
 293     struct gmx_sel_mempool_t           *mempool;
 294     /** Internal data for the selection compiler. */
 295     struct t_compiler_data             *cdata;
 296
 297     /*! \brief The first child element.
 298      *
 299      * Other children can be accessed through the \p next field of \p child.
 300      */
 301     struct t_selelem                    *child;
 302     /** The next sibling element. */
 303     struct t_selelem                    *next;
 304     /*! \brief Number of references to this element.
 305      *
 306      * Should be larger than one only for \ref SEL_SUBEXPR elements.
 307      */
 308     int                                  refcount;
 309 } t_selelem;
 310
 311 /** Allocates memory and performs some common initialization for a \c t_selelem. */
 312 extern t_selelem *
 313 _gmx_selelem_create(e_selelem_t type);
 314 /** Sets the value type of a \c t_selelem. */
 315 extern int
 316 _gmx_selelem_set_vtype(t_selelem *sel, e_selvalue_t vtype);
 317 /** Reserves memory for value of a \c t_selelem from a memory pool. */
 318 extern int
 319 _gmx_selelem_mempool_reserve(t_selelem *sel, int count);
 320 /** Releases memory pool used for value of a \c t_selelem. */
 321 extern void
 322 _gmx_selelem_mempool_release(t_selelem *sel);
 323 /** Frees the memory allocated for a \c t_selelem structure and all its children. */
 324 extern void
 325 _gmx_selelem_free(t_selelem *sel);
 326 /** Frees the memory allocated for a \c t_selelem structure, all its children, and also all structures referenced through t_selelem::next fields. */
 327 extern void
 328 _gmx_selelem_free_chain(t_selelem *first);
 329
 330 /** Frees the memory allocated for the \c t_selelem::d union. */
 331 extern void
 332 _gmx_selelem_free_values(t_selelem *sel);
 333 /** Frees the memory allocated for a selection method. */
 334 extern void
 335 _gmx_selelem_free_method(struct gmx_ana_selmethod_t *method, void *mdata);
 336 /** Frees the memory allocated for the \c t_selelem::u field. */
 337 extern void
 338 _gmx_selelem_free_exprdata(t_selelem *sel);
 339 /* In compiler.c */
 340 /** Frees the memory allocated for the selection compiler. */
 341 extern void
 342 _gmx_selelem_free_compiler_data(t_selelem *sel);
 343
 344 /** Prints a human-readable version of a selection element subtree. */
 345 extern void
 346 _gmx_selelem_print_tree(FILE *fp, t_selelem *root, bool bValues, int level);
 347
 348 /** Returns TRUE if the selection element subtree requires topology information for evaluation. */
 349 extern bool
 350 _gmx_selelem_requires_top(t_selelem *root);
 351
 352 /* In sm_insolidangle.c */
 353 /** Returns TRUE if the covered fraction of the selection can be calculated. */
 354 extern bool
 355 _gmx_selelem_can_estimate_cover(t_selelem *sel);
 356 /** Returns the covered fraction of the selection for the current frame. */
 357 extern real
 358 _gmx_selelem_estimate_coverfrac(t_selelem *sel);
 359
 360 /*@}*/
 361
 362 #endif