include/babeltrace/types.h

   1 #ifndef _BABELTRACE_TYPES_H
   2 #define _BABELTRACE_TYPES_H
   3
   4 /*
   5  * BabelTrace
   6  *
   7  * Type Header
   8  *
   9  * Copyright 2010, 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a copy
  12  * of this software and associated documentation files (the "Software"), to deal
  13  * in the Software without restriction, including without limitation the rights
  14  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  15  * copies of the Software, and to permit persons to whom the Software is
  16  * furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included in
  19  * all copies or substantial portions of the Software.
  20  */
  21
  22 #include <babeltrace/align.h>
  23 #include <babeltrace/list.h>
  24 #include <stdbool.h>
  25 #include <stdint.h>
  26 #include <limits.h>
  27 #include <string.h>
  28 #include <glib.h>
  29 #include <assert.h>
  30
  31 /* Preallocate this many fields for structures */
  32 #define DEFAULT_NR_STRUCT_FIELDS 8
  33
  34 /*
  35  * Always update stream_pos with move_pos and init_pos.
  36  */
  37 struct stream_pos {
  38         char *base;             /* Base address */
  39         size_t offset;          /* Offset from base, in bits */
  40         int dummy;              /* Dummy position, for length calculation */
  41 };
  42
  43 static inline
  44 void init_pos(struct stream_pos *pos, char *base)
  45 {
  46         pos->base = base;       /* initial base, page-aligned */
  47         pos->offset = 0;
  48         pos->dummy = false;
  49 }
  50
  51 /*
  52  * move_pos - move position of a relative bit offset
  53  *
  54  * TODO: allow larger files by updating base too.
  55  */
  56 static inline
  57 void move_pos(struct stream_pos *pos, size_t offset)
  58 {
  59         pos->offset = pos->offset + offset;
  60 }
  61
  62 /*
  63  * align_pos - align position on a bit offset (> 0)
  64  *
  65  * TODO: allow larger files by updating base too.
  66  */
  67 static inline
  68 void align_pos(struct stream_pos *pos, size_t offset)
  69 {
  70         pos->offset += offset_align(pos->offset, offset);
  71 }
  72
  73 static inline
  74 void copy_pos(struct stream_pos *dest, struct stream_pos *src)
  75 {
  76         memcpy(dest, src, sizeof(struct stream_pos));
  77 }
  78
  79 static inline
  80 char *get_pos_addr(struct stream_pos *pos)
  81 {
  82         /* Only makes sense to get the address after aligning on CHAR_BIT */
  83         assert(!(pos->offset % CHAR_BIT));
  84         return pos->base + (pos->offset / CHAR_BIT);
  85 }
  86
  87 struct format;
  88 struct definition;
  89
  90 /* type scope */
  91 struct declaration_scope {
  92         /* Hash table mapping type name GQuark to "struct declaration" */
  93         GHashTable *typedef_declarations;
  94         /* Hash table mapping struct name GQuark to "struct declaration_struct" */
  95         GHashTable *struct_declarations;
  96         /* Hash table mapping variant name GQuark to "struct declaration_variant" */
  97         GHashTable *variant_declarations;
  98         /* Hash table mapping enum name GQuark to "struct type_enum" */
  99         GHashTable *enum_declarations;
 100         struct declaration_scope *parent_scope;
 101 };
 102
 103 /* definition scope */
 104 struct definition_scope {
 105         /* Hash table mapping field name GQuark to "struct definition" */
 106         GHashTable *definitions;
 107         struct definition_scope *parent_scope;
 108         /*
 109          * Complete "path" leading to this definition scope.
 110          * Includes dynamic scope name '.' field name '.' field name '.' ....
 111          * Array of GQuark elements (which are each separated by dots).
 112          * The dynamic scope name can contain dots, and is encoded into
 113          * a single GQuark. Thus, scope_path[0] returns the GQuark
 114          * identifying the dynamic scope.
 115          */
 116         GArray *scope_path;     /* array of GQuark */
 117 };
 118
 119 enum ctf_type_id {
 120         CTF_TYPE_UNKNOWN = 0,
 121         CTF_TYPE_INTEGER,
 122         CTF_TYPE_FLOAT,
 123         CTF_TYPE_ENUM,
 124         CTF_TYPE_STRING,
 125         CTF_TYPE_STRUCT,
 126         CTF_TYPE_VARIANT,
 127         CTF_TYPE_ARRAY,
 128         CTF_TYPE_SEQUENCE,
 129         NR_CTF_TYPES,
 130 };
 131
 132 struct declaration {
 133         enum ctf_type_id id;
 134         GQuark name;            /* type name */
 135         size_t alignment;       /* type alignment, in bits */
 136         int ref;                /* number of references to the type */
 137         /*
 138          * declaration_free called with declaration ref is decremented to 0.
 139          */
 140         void (*declaration_free)(struct declaration *declaration);
 141         struct definition *
 142                 (*definition_new)(struct declaration *declaration,
 143                                   struct definition_scope *parent_scope,
 144                                   GQuark field_name, int index);
 145         /*
 146          * definition_free called with definition ref is decremented to 0.
 147          */
 148         void (*definition_free)(struct definition *definition);
 149         /*
 150          * Definition copy function. Knows how to find the child
 151          * definition from the parent definition.
 152          */
 153         void (*copy)(struct stream_pos *dest, const struct format *fdest,
 154                      struct stream_pos *src, const struct format *fsrc,
 155                      struct definition *definition);
 156 };
 157
 158 struct definition {
 159         struct declaration *declaration;
 160         int index;              /* Position of the definition in its container */
 161         int ref;                /* number of references to the definition */
 162 };
 163
 164 /*
 165  * Because we address in bits, bitfields end up being exactly the same as
 166  * integers, except that their read/write functions must be able to deal with
 167  * read/write non aligned on CHAR_BIT.
 168  */
 169 struct declaration_integer {
 170         struct declaration p;
 171         size_t len;             /* length, in bits. */
 172         int byte_order;         /* byte order */
 173         int signedness;
 174 };
 175
 176 struct definition_integer {
 177         struct definition p;
 178         struct declaration_integer *declaration;
 179         /* Last values read */
 180         union {
 181                 uint64_t _unsigned;
 182                 int64_t _signed;
 183         } value;
 184 };
 185
 186 struct declaration_float {
 187         struct declaration p;
 188         struct declaration_integer *sign;
 189         struct declaration_integer *mantissa;
 190         struct declaration_integer *exp;
 191         int byte_order;
 192         /* TODO: we might want to express more info about NaN, +inf and -inf */
 193 };
 194
 195 struct definition_float {
 196         struct definition p;
 197         struct declaration_float *declaration;
 198         /* Last values read */
 199         long double value;
 200 };
 201
 202 /*
 203  * enum_val_equal assumes that signed and unsigned memory layout overlap.
 204  */
 205 struct enum_range {
 206         union {
 207                 int64_t _signed;
 208                 uint64_t _unsigned;
 209         } start;        /* lowest range value */
 210         union {
 211                 int64_t _signed;
 212                 uint64_t _unsigned;
 213         } end;          /* highest range value */
 214 };
 215
 216 struct enum_range_to_quark {
 217         struct cds_list_head node;
 218         struct enum_range range;
 219         GQuark quark;
 220 };
 221
 222 /*
 223  * We optimize the common case (range of size 1: single value) by creating a
 224  * hash table mapping values to quark sets. We then lookup the ranges to
 225  * complete the quark set.
 226  *
 227  * TODO: The proper structure to hold the range to quark set mapping would be an
 228  * interval tree, with O(n) size, O(n*log(n)) build time and O(log(n)) query
 229  * time. Using a simple O(n) list search for now for implementation speed and
 230  * given that we can expect to have a _relatively_ small number of enumeration
 231  * ranges. This might become untrue if we are fed with symbol tables often
 232  * required to lookup function names from instruction pointer value.
 233  */
 234 struct enum_table {
 235         GHashTable *value_to_quark_set;         /* (value, GQuark GArray) */
 236         struct cds_list_head range_to_quark;    /* (range, GQuark) */
 237         GHashTable *quark_to_range_set;         /* (GQuark, range GArray) */
 238 };
 239
 240 struct declaration_enum {
 241         struct declaration p;
 242         struct declaration_integer *integer_declaration;
 243         struct enum_table table;
 244 };
 245
 246 struct definition_enum {
 247         struct definition p;
 248         struct definition_integer *integer;
 249         struct declaration_enum *declaration;
 250         /* Last GQuark values read. Keeping a reference on the GQuark array. */
 251         GArray *value;
 252 };
 253
 254 struct declaration_string {
 255         struct declaration p;
 256 };
 257
 258 struct definition_string {
 259         struct definition p;
 260         struct declaration_string *declaration;
 261         char *value;    /* freed at definition_string teardown */
 262 };
 263
 264 struct declaration_field {
 265         GQuark name;
 266         struct declaration *declaration;
 267 };
 268
 269 struct field {
 270         GQuark name;
 271         struct definition *definition;
 272 };
 273
 274 struct declaration_struct {
 275         struct declaration p;
 276         GHashTable *fields_by_name;     /* Tuples (field name, field index) */
 277         struct declaration_scope *scope;
 278         GArray *fields;                 /* Array of declaration_field */
 279 };
 280
 281 struct definition_struct {
 282         struct definition p;
 283         struct declaration_struct *declaration;
 284         struct definition_scope *scope;
 285         GArray *fields;                 /* Array of struct field */
 286 };
 287
 288 struct declaration_variant {
 289         struct declaration p;
 290         GHashTable *fields_by_tag;      /* Tuples (field tag, field index) */
 291         struct declaration_scope *scope;
 292         GArray *fields;                 /* Array of declaration_field */
 293         GQuark tag_name;                /* TODO */
 294         /* Tag name must be nonzero and must exist when defining the variant */
 295 };
 296
 297 struct definition_variant {
 298         struct definition p;
 299         struct declaration_variant *declaration;
 300         struct definition_scope *scope;
 301         struct definition *enum_tag;
 302         GArray *fields;                 /* Array of struct field */
 303         struct field *current_field;    /* Last field read */
 304 };
 305
 306 struct declaration_array {
 307         struct declaration p;
 308         size_t len;
 309         struct declaration *elem;
 310         struct declaration_scope *scope;
 311 };
 312
 313 struct definition_array {
 314         struct definition p;
 315         struct declaration_array *declaration;
 316         struct definition_scope *scope;
 317         struct field current_element;           /* struct field */
 318 };
 319
 320 struct declaration_sequence {
 321         struct declaration p;
 322         struct declaration_integer *len_declaration;
 323         struct declaration *elem;
 324         struct declaration_scope *scope;
 325 };
 326
 327 struct definition_sequence {
 328         struct definition p;
 329         struct declaration_sequence *declaration;
 330         struct definition_scope *scope;
 331         struct definition_integer *len;
 332         struct field current_element;           /* struct field */
 333 };
 334
 335 int register_declaration(GQuark declaration_name,
 336                          struct declaration *declaration,
 337                          struct declaration_scope *scope);
 338 struct declaration *lookup_declaration(GQuark declaration_name,
 339                                        struct declaration_scope *scope);
 340
 341 /*
 342  * Type scopes also contain a separate registry for struct, variant and
 343  * enum types. Those register types rather than type definitions, so
 344  * that a named variant can be declared without specifying its target
 345  * "choice" tag field immediately.
 346  */
 347 int register_struct_declaration(GQuark struct_name,
 348                                 struct declaration_struct *struct_declaration,
 349                                 struct declaration_scope *scope);
 350 struct declaration_struct *
 351         lookup_struct_declaration(GQuark struct_name,
 352                                   struct declaration_scope *scope);
 353 int register_variant_declaration(GQuark variant_name,
 354                           struct declaration_variant *variant_declaration,
 355                           struct declaration_scope *scope);
 356 struct declaration_variant *lookup_variant_declaration(GQuark variant_name,
 357                                          struct declaration_scope *scope);
 358 int register_enum_declaration(GQuark enum_name,
 359                               struct declaration_enum *enum_declaration,
 360                               struct declaration_scope *scope);
 361 struct declaration_enum *
 362         lookup_enum_declaration(GQuark enum_name,
 363                                 struct declaration_scope *scope);
 364
 365 struct declaration_scope *
 366         new_declaration_scope(struct declaration_scope *parent_scope);
 367 void free_declaration_scope(struct declaration_scope *scope);
 368
 369 /*
 370  * field_definition is for field definitions. They are registered into
 371  * definition scopes.
 372  */
 373 struct definition *
 374         lookup_definition(GArray *cur_path,     /* array of GQuark */
 375                           GArray *lookup_path,  /* array of GQuark */
 376                           struct definition_scope *scope);
 377 int register_field_definition(GQuark field_name,
 378                               struct definition *definition,
 379                               struct definition_scope *scope);
 380 struct definition_scope *
 381         new_definition_scope(struct definition_scope *parent_scope,
 382                              GQuark field_name);
 383 void set_dynamic_definition_scope(struct definition *definition,
 384                                   struct definition_scope *scope,
 385                                   const char *root_name);
 386 void free_definition_scope(struct definition_scope *scope);
 387
 388 void declaration_ref(struct declaration *declaration);
 389 void declaration_unref(struct declaration *declaration);
 390
 391 void definition_ref(struct definition *definition);
 392 void definition_unref(struct definition *definition);
 393
 394 /* Nameless declarations can be created by passing a NULL name */
 395
 396 struct declaration_integer *integer_declaration_new(const char *name,
 397                                       size_t len, int byte_order,
 398                                       int signedness, size_t alignment);
 399
 400 /*
 401  * mantissa_len is the length of the number of bytes represented by the mantissa
 402  * (e.g. result of DBL_MANT_DIG). It includes the leading 1.
 403  */
 404 struct declaration_float *float_declaration_new(const char *name,
 405                                   size_t mantissa_len,
 406                                   size_t exp_len, int byte_order,
 407                                   size_t alignment);
 408
 409 /*
 410  * A GQuark can be translated to/from strings with g_quark_from_string() and
 411  * g_quark_to_string().
 412  */
 413
 414 /*
 415  * Returns a GArray of GQuark or NULL.
 416  * Caller must release the GArray with g_array_unref().
 417  */
 418 GArray *enum_uint_to_quark_set(const struct declaration_enum *enum_declaration,
 419                                uint64_t v);
 420
 421 /*
 422  * Returns a GArray of GQuark or NULL.
 423  * Caller must release the GArray with g_array_unref().
 424  */
 425 GArray *enum_int_to_quark_set(const struct declaration_enum *enum_declaration,
 426                               uint64_t v);
 427
 428 /*
 429  * Returns a GArray of struct enum_range or NULL.
 430  * Callers do _not_ own the returned GArray (and therefore _don't_ need to
 431  * release it).
 432  */
 433 GArray *enum_quark_to_range_set(const struct declaration_enum *enum_declaration,
 434                                 GQuark q);
 435 void enum_signed_insert(struct declaration_enum *enum_declaration,
 436                         int64_t start, int64_t end, GQuark q);
 437 void enum_unsigned_insert(struct declaration_enum *enum_declaration,
 438                           uint64_t start, uint64_t end, GQuark q);
 439 size_t enum_get_nr_enumerators(struct declaration_enum *enum_declaration);
 440
 441 struct declaration_enum *
 442         enum_declaration_new(const char *name,
 443                              struct declaration_integer *integer_declaration);
 444
 445 struct declaration_struct *
 446         struct_declaration_new(const char *name,
 447                                struct declaration_scope *parent_scope);
 448 void struct_declaration_add_field(struct declaration_struct *struct_declaration,
 449                                   const char *field_name,
 450                                   struct declaration *field_declaration);
 451 /*
 452  * Returns the index of a field within a structure.
 453  */
 454 unsigned long struct_declaration_lookup_field_index(struct declaration_struct *struct_declaration,
 455                                                     GQuark field_name);
 456 /*
 457  * field returned only valid as long as the field structure is not appended to.
 458  */
 459 struct declaration_field *
 460 struct_declaration_get_field_from_index(struct declaration_struct *struct_declaration,
 461                                         unsigned long index);
 462 struct field *
 463 struct_get_field_from_index(struct definition_struct *struct_definition,
 464                             unsigned long index);
 465
 466 /*
 467  * The tag enumeration is validated to ensure that it contains only mappings
 468  * from numeric values to a single tag. Overlapping tag value ranges are
 469  * therefore forbidden.
 470  */
 471 struct declaration_variant *variant_declaration_new(const char *name,
 472                 struct declaration_scope *parent_scope);
 473 void variant_declaration_add_field(struct declaration_variant *variant_declaration,
 474                 const char *tag_name,
 475                 struct declaration *tag_declaration);
 476 struct declaration_field *
 477         variant_declaration_get_field_from_tag(struct declaration_variant *variant_declaration,
 478                 GQuark tag);
 479 /*
 480  * Returns 0 on success, -EPERM on error.
 481  */
 482 int variant_definition_set_tag(struct definition_variant *variant,
 483                                struct definition *enum_tag);
 484 /*
 485  * Returns the field selected by the current tag value.
 486  * field returned only valid as long as the variant structure is not appended
 487  * to.
 488  */
 489 struct field *variant_get_current_field(struct definition_variant *variant);
 490
 491 /*
 492  * elem_declaration passed as parameter now belongs to the array. No
 493  * need to free it explicitly. "len" is the number of elements in the
 494  * array.
 495  */
 496 struct declaration_array *
 497         array_declaration_new(const char *name,
 498                 size_t len, struct declaration *elem_declaration,
 499                 struct declaration_scope *parent_scope);
 500
 501 /*
 502  * int_declaration and elem_declaration passed as parameter now belong
 503  * to the sequence. No need to free them explicitly.
 504  */
 505 struct declaration_sequence *
 506         sequence_declaration_new(const char *name,
 507                 struct declaration_integer *len_declaration,
 508                 struct declaration *elem_declaration,
 509                 struct declaration_scope *parent_scope);
 510
 511 #endif /* _BABELTRACE_declarationS_H */