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         /* Used for both typedef and typealias. */
  94         GHashTable *typedef_declarations;
  95         /* Hash table mapping struct name GQuark to "struct declaration_struct" */
  96         GHashTable *struct_declarations;
  97         /* Hash table mapping variant name GQuark to "struct declaration_variant" */
  98         GHashTable *variant_declarations;
  99         /* Hash table mapping enum name GQuark to "struct type_enum" */
 100         GHashTable *enum_declarations;
 101         struct declaration_scope *parent_scope;
 102 };
 103
 104 /* definition scope */
 105 struct definition_scope {
 106         /* Hash table mapping field name GQuark to "struct definition" */
 107         GHashTable *definitions;
 108         struct definition_scope *parent_scope;
 109         /*
 110          * Complete "path" leading to this definition scope.
 111          * Includes dynamic scope name '.' field name '.' field name '.' ....
 112          * Array of GQuark elements (which are each separated by dots).
 113          * The dynamic scope name can contain dots, and is encoded into
 114          * a single GQuark. Thus, scope_path[0] returns the GQuark
 115          * identifying the dynamic scope.
 116          */
 117         GArray *scope_path;     /* array of GQuark */
 118 };
 119
 120 enum ctf_type_id {
 121         CTF_TYPE_UNKNOWN = 0,
 122         CTF_TYPE_INTEGER,
 123         CTF_TYPE_FLOAT,
 124         CTF_TYPE_ENUM,
 125         CTF_TYPE_STRING,
 126         CTF_TYPE_STRUCT,
 127         CTF_TYPE_UNTAGGED_VARIANT,
 128         CTF_TYPE_VARIANT,
 129         CTF_TYPE_ARRAY,
 130         CTF_TYPE_SEQUENCE,
 131         NR_CTF_TYPES,
 132 };
 133
 134 struct declaration {
 135         enum ctf_type_id id;
 136         GQuark name;            /* type name */
 137         size_t alignment;       /* type alignment, in bits */
 138         int ref;                /* number of references to the type */
 139         /*
 140          * declaration_free called with declaration ref is decremented to 0.
 141          */
 142         void (*declaration_free)(struct declaration *declaration);
 143         struct definition *
 144                 (*definition_new)(struct declaration *declaration,
 145                                   struct definition_scope *parent_scope,
 146                                   GQuark field_name, int index);
 147         /*
 148          * definition_free called with definition ref is decremented to 0.
 149          */
 150         void (*definition_free)(struct definition *definition);
 151         /*
 152          * Definition copy function. Knows how to find the child
 153          * definition from the parent definition.
 154          */
 155         void (*copy)(struct stream_pos *dest, const struct format *fdest,
 156                      struct stream_pos *src, const struct format *fsrc,
 157                      struct definition *definition);
 158 };
 159
 160 struct definition {
 161         struct declaration *declaration;
 162         int index;              /* Position of the definition in its container */
 163         int ref;                /* number of references to the definition */
 164 };
 165
 166 /*
 167  * Because we address in bits, bitfields end up being exactly the same as
 168  * integers, except that their read/write functions must be able to deal with
 169  * read/write non aligned on CHAR_BIT.
 170  */
 171 struct declaration_integer {
 172         struct declaration p;
 173         size_t len;             /* length, in bits. */
 174         int byte_order;         /* byte order */
 175         int signedness;
 176 };
 177
 178 struct definition_integer {
 179         struct definition p;
 180         struct declaration_integer *declaration;
 181         /* Last values read */
 182         union {
 183                 uint64_t _unsigned;
 184                 int64_t _signed;
 185         } value;
 186 };
 187
 188 struct declaration_float {
 189         struct declaration p;
 190         struct declaration_integer *sign;
 191         struct declaration_integer *mantissa;
 192         struct declaration_integer *exp;
 193         int byte_order;
 194         /* TODO: we might want to express more info about NaN, +inf and -inf */
 195 };
 196
 197 struct definition_float {
 198         struct definition p;
 199         struct declaration_float *declaration;
 200         /* Last values read */
 201         long double value;
 202 };
 203
 204 /*
 205  * enum_val_equal assumes that signed and unsigned memory layout overlap.
 206  */
 207 struct enum_range {
 208         union {
 209                 int64_t _signed;
 210                 uint64_t _unsigned;
 211         } start;        /* lowest range value */
 212         union {
 213                 int64_t _signed;
 214                 uint64_t _unsigned;
 215         } end;          /* highest range value */
 216 };
 217
 218 struct enum_range_to_quark {
 219         struct cds_list_head node;
 220         struct enum_range range;
 221         GQuark quark;
 222 };
 223
 224 /*
 225  * We optimize the common case (range of size 1: single value) by creating a
 226  * hash table mapping values to quark sets. We then lookup the ranges to
 227  * complete the quark set.
 228  *
 229  * TODO: The proper structure to hold the range to quark set mapping would be an
 230  * interval tree, with O(n) size, O(n*log(n)) build time and O(log(n)) query
 231  * time. Using a simple O(n) list search for now for implementation speed and
 232  * given that we can expect to have a _relatively_ small number of enumeration
 233  * ranges. This might become untrue if we are fed with symbol tables often
 234  * required to lookup function names from instruction pointer value.
 235  */
 236 struct enum_table {
 237         GHashTable *value_to_quark_set;         /* (value, GQuark GArray) */
 238         struct cds_list_head range_to_quark;    /* (range, GQuark) */
 239         GHashTable *quark_to_range_set;         /* (GQuark, range GArray) */
 240 };
 241
 242 struct declaration_enum {
 243         struct declaration p;
 244         struct declaration_integer *integer_declaration;
 245         struct enum_table table;
 246 };
 247
 248 struct definition_enum {
 249         struct definition p;
 250         struct definition_integer *integer;
 251         struct declaration_enum *declaration;
 252         /* Last GQuark values read. Keeping a reference on the GQuark array. */
 253         GArray *value;
 254 };
 255
 256 struct declaration_string {
 257         struct declaration p;
 258 };
 259
 260 struct definition_string {
 261         struct definition p;
 262         struct declaration_string *declaration;
 263         char *value;    /* freed at definition_string teardown */
 264 };
 265
 266 struct declaration_field {
 267         GQuark name;
 268         struct declaration *declaration;
 269 };
 270
 271 struct field {
 272         GQuark name;
 273         struct definition *definition;
 274 };
 275
 276 struct declaration_struct {
 277         struct declaration p;
 278         GHashTable *fields_by_name;     /* Tuples (field name, field index) */
 279         struct declaration_scope *scope;
 280         GArray *fields;                 /* Array of declaration_field */
 281 };
 282
 283 struct definition_struct {
 284         struct definition p;
 285         struct declaration_struct *declaration;
 286         struct definition_scope *scope;
 287         GArray *fields;                 /* Array of struct field */
 288 };
 289
 290 struct declaration_untagged_variant {
 291         struct declaration p;
 292         GHashTable *fields_by_tag;      /* Tuples (field tag, field index) */
 293         struct declaration_scope *scope;
 294         GArray *fields;                 /* Array of declaration_field */
 295 };
 296
 297 struct declaration_variant {
 298         struct declaration p;
 299         struct declaration_untagged_variant *untagged_variant;
 300         GArray *tag_name;               /* Array of GQuark */
 301 };
 302
 303 /* A variant needs to be tagged to be defined. */
 304 struct definition_variant {
 305         struct definition p;
 306         struct declaration_variant *declaration;
 307         struct definition_scope *scope;
 308         struct definition *enum_tag;
 309         GArray *fields;                 /* Array of struct field */
 310         struct field *current_field;    /* Last field read */
 311 };
 312
 313 struct declaration_array {
 314         struct declaration p;
 315         size_t len;
 316         struct declaration *elem;
 317         struct declaration_scope *scope;
 318 };
 319
 320 struct definition_array {
 321         struct definition p;
 322         struct declaration_array *declaration;
 323         struct definition_scope *scope;
 324         struct field current_element;           /* struct field */
 325 };
 326
 327 struct declaration_sequence {
 328         struct declaration p;
 329         struct declaration_integer *len_declaration;
 330         struct declaration *elem;
 331         struct declaration_scope *scope;
 332 };
 333
 334 struct definition_sequence {
 335         struct definition p;
 336         struct declaration_sequence *declaration;
 337         struct definition_scope *scope;
 338         struct definition_integer *len;
 339         struct field current_element;           /* struct field */
 340 };
 341
 342 int register_declaration(GQuark declaration_name,
 343                          struct declaration *declaration,
 344                          struct declaration_scope *scope);
 345 struct declaration *lookup_declaration(GQuark declaration_name,
 346                                        struct declaration_scope *scope);
 347
 348 /*
 349  * Type scopes also contain a separate registry for struct, variant and
 350  * enum types. Those register types rather than type definitions, so
 351  * that a named variant can be declared without specifying its target
 352  * "choice" tag field immediately.
 353  */
 354 int register_struct_declaration(GQuark struct_name,
 355                                 struct declaration_struct *struct_declaration,
 356                                 struct declaration_scope *scope);
 357 struct declaration_struct *
 358         lookup_struct_declaration(GQuark struct_name,
 359                                   struct declaration_scope *scope);
 360 int register_variant_declaration(GQuark variant_name,
 361                           struct declaration_variant *variant_declaration,
 362                           struct declaration_scope *scope);
 363 struct declaration_variant *lookup_variant_declaration(GQuark variant_name,
 364                                          struct declaration_scope *scope);
 365 int register_enum_declaration(GQuark enum_name,
 366                               struct declaration_enum *enum_declaration,
 367                               struct declaration_scope *scope);
 368 struct declaration_enum *
 369         lookup_enum_declaration(GQuark enum_name,
 370                                 struct declaration_scope *scope);
 371
 372 struct declaration_scope *
 373         new_declaration_scope(struct declaration_scope *parent_scope);
 374 void free_declaration_scope(struct declaration_scope *scope);
 375
 376 /*
 377  * field_definition is for field definitions. They are registered into
 378  * definition scopes.
 379  */
 380 struct definition *
 381         lookup_definition(GArray *cur_path,     /* array of GQuark */
 382                           GArray *lookup_path,  /* array of GQuark */
 383                           struct definition_scope *scope);
 384 int register_field_definition(GQuark field_name,
 385                               struct definition *definition,
 386                               struct definition_scope *scope);
 387 struct definition_scope *
 388         new_definition_scope(struct definition_scope *parent_scope,
 389                              GQuark field_name);
 390 void set_dynamic_definition_scope(struct definition *definition,
 391                                   struct definition_scope *scope,
 392                                   const char *root_name);
 393 void free_definition_scope(struct definition_scope *scope);
 394
 395 void declaration_ref(struct declaration *declaration);
 396 void declaration_unref(struct declaration *declaration);
 397
 398 void definition_ref(struct definition *definition);
 399 void definition_unref(struct definition *definition);
 400
 401 struct declaration_integer *integer_declaration_new(size_t len, int byte_order,
 402                                       int signedness, size_t alignment);
 403
 404 /*
 405  * mantissa_len is the length of the number of bytes represented by the mantissa
 406  * (e.g. result of DBL_MANT_DIG). It includes the leading 1.
 407  */
 408 struct declaration_float *float_declaration_new(size_t mantissa_len,
 409                                   size_t exp_len, int byte_order,
 410                                   size_t alignment);
 411
 412 /*
 413  * A GQuark can be translated to/from strings with g_quark_from_string() and
 414  * g_quark_to_string().
 415  */
 416
 417 /*
 418  * Returns a GArray of GQuark or NULL.
 419  * Caller must release the GArray with g_array_unref().
 420  */
 421 GArray *enum_uint_to_quark_set(const struct declaration_enum *enum_declaration,
 422                                uint64_t v);
 423
 424 /*
 425  * Returns a GArray of GQuark or NULL.
 426  * Caller must release the GArray with g_array_unref().
 427  */
 428 GArray *enum_int_to_quark_set(const struct declaration_enum *enum_declaration,
 429                               uint64_t v);
 430
 431 /*
 432  * Returns a GArray of struct enum_range or NULL.
 433  * Callers do _not_ own the returned GArray (and therefore _don't_ need to
 434  * release it).
 435  */
 436 GArray *enum_quark_to_range_set(const struct declaration_enum *enum_declaration,
 437                                 GQuark q);
 438 void enum_signed_insert(struct declaration_enum *enum_declaration,
 439                         int64_t start, int64_t end, GQuark q);
 440 void enum_unsigned_insert(struct declaration_enum *enum_declaration,
 441                           uint64_t start, uint64_t end, GQuark q);
 442 size_t enum_get_nr_enumerators(struct declaration_enum *enum_declaration);
 443
 444 struct declaration_enum *
 445         enum_declaration_new(const char *name,
 446                              struct declaration_integer *integer_declaration);
 447
 448 struct declaration_struct *
 449         struct_declaration_new(const char *name,
 450                                struct declaration_scope *parent_scope);
 451 void struct_declaration_add_field(struct declaration_struct *struct_declaration,
 452                                   const char *field_name,
 453                                   struct declaration *field_declaration);
 454 /*
 455  * Returns the index of a field within a structure.
 456  */
 457 unsigned long struct_declaration_lookup_field_index(struct declaration_struct *struct_declaration,
 458                                                     GQuark field_name);
 459 /*
 460  * field returned only valid as long as the field structure is not appended to.
 461  */
 462 struct declaration_field *
 463 struct_declaration_get_field_from_index(struct declaration_struct *struct_declaration,
 464                                         unsigned long index);
 465 struct field *
 466 struct_get_field_from_index(struct definition_struct *struct_definition,
 467                             unsigned long index);
 468
 469 /*
 470  * The tag enumeration is validated to ensure that it contains only mappings
 471  * from numeric values to a single tag. Overlapping tag value ranges are
 472  * therefore forbidden.
 473  */
 474 struct declaration_untagged_variant *untagged_variant_declaration_new(const char *name,
 475                 struct declaration_scope *parent_scope);
 476 struct declaration_variant *variant_declaration_new(struct declaration_untagged_variant *untagged_variant,
 477                 const char *tag);
 478
 479 void untagged_variant_declaration_add_field(struct declaration_untagged_variant *untagged_variant_declaration,
 480                 const char *field_name,
 481                 struct declaration *field_declaration);
 482 struct declaration_field *
 483         untagged_variant_declaration_get_field_from_tag(struct declaration_untagged_variant *untagged_variant_declaration,
 484                 GQuark tag);
 485 /*
 486  * Returns 0 on success, -EPERM on error.
 487  */
 488 int variant_definition_set_tag(struct definition_variant *variant,
 489                                struct definition *enum_tag);
 490 /*
 491  * Returns the field selected by the current tag value.
 492  * field returned only valid as long as the variant structure is not appended
 493  * to.
 494  */
 495 struct field *variant_get_current_field(struct definition_variant *variant);
 496
 497 /*
 498  * elem_declaration passed as parameter now belongs to the array. No
 499  * need to free it explicitly. "len" is the number of elements in the
 500  * array.
 501  */
 502 struct declaration_array *
 503         array_declaration_new(const char *name,
 504                 size_t len, struct declaration *elem_declaration,
 505                 struct declaration_scope *parent_scope);
 506
 507 /*
 508  * int_declaration and elem_declaration passed as parameter now belong
 509  * to the sequence. No need to free them explicitly.
 510  */
 511 struct declaration_sequence *
 512         sequence_declaration_new(const char *name,
 513                 struct declaration_integer *len_declaration,
 514                 struct declaration *elem_declaration,
 515                 struct declaration_scope *parent_scope);
 516
 517 /*
 518  * in: path (dot separated), out: q (GArray of GQuark)
 519  */
 520 void append_scope_path(const char *path, GArray *q);
 521
 522 #endif /* _BABELTRACE_declarationS_H */