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         size_t alignment;       /* type alignment, in bits */
 137         int ref;                /* number of references to the type */
 138         /*
 139          * declaration_free called with declaration ref is decremented to 0.
 140          */
 141         void (*declaration_free)(struct declaration *declaration);
 142         struct definition *
 143                 (*definition_new)(struct declaration *declaration,
 144                                   struct definition_scope *parent_scope,
 145                                   GQuark field_name, int index);
 146         /*
 147          * definition_free called with definition ref is decremented to 0.
 148          */
 149         void (*definition_free)(struct definition *definition);
 150         /*
 151          * Definition copy function. Knows how to find the child
 152          * definition from the parent definition.
 153          */
 154         void (*copy)(struct stream_pos *dest, const struct format *fdest,
 155                      struct stream_pos *src, const struct format *fsrc,
 156                      struct definition *definition);
 157 };
 158
 159 struct definition {
 160         struct declaration *declaration;
 161         int index;              /* Position of the definition in its container */
 162         int ref;                /* number of references to the definition */
 163 };
 164
 165 /*
 166  * Because we address in bits, bitfields end up being exactly the same as
 167  * integers, except that their read/write functions must be able to deal with
 168  * read/write non aligned on CHAR_BIT.
 169  */
 170 struct declaration_integer {
 171         struct declaration p;
 172         size_t len;             /* length, in bits. */
 173         int byte_order;         /* byte order */
 174         int signedness;
 175 };
 176
 177 struct definition_integer {
 178         struct definition p;
 179         struct declaration_integer *declaration;
 180         /* Last values read */
 181         union {
 182                 uint64_t _unsigned;
 183                 int64_t _signed;
 184         } value;
 185 };
 186
 187 struct declaration_float {
 188         struct declaration p;
 189         struct declaration_integer *sign;
 190         struct declaration_integer *mantissa;
 191         struct declaration_integer *exp;
 192         int byte_order;
 193         /* TODO: we might want to express more info about NaN, +inf and -inf */
 194 };
 195
 196 struct definition_float {
 197         struct definition p;
 198         struct declaration_float *declaration;
 199         /* Last values read */
 200         long double value;
 201 };
 202
 203 /*
 204  * enum_val_equal assumes that signed and unsigned memory layout overlap.
 205  */
 206 struct enum_range {
 207         union {
 208                 int64_t _signed;
 209                 uint64_t _unsigned;
 210         } start;        /* lowest range value */
 211         union {
 212                 int64_t _signed;
 213                 uint64_t _unsigned;
 214         } end;          /* highest range value */
 215 };
 216
 217 struct enum_range_to_quark {
 218         struct cds_list_head node;
 219         struct enum_range range;
 220         GQuark quark;
 221 };
 222
 223 /*
 224  * We optimize the common case (range of size 1: single value) by creating a
 225  * hash table mapping values to quark sets. We then lookup the ranges to
 226  * complete the quark set.
 227  *
 228  * TODO: The proper structure to hold the range to quark set mapping would be an
 229  * interval tree, with O(n) size, O(n*log(n)) build time and O(log(n)) query
 230  * time. Using a simple O(n) list search for now for implementation speed and
 231  * given that we can expect to have a _relatively_ small number of enumeration
 232  * ranges. This might become untrue if we are fed with symbol tables often
 233  * required to lookup function names from instruction pointer value.
 234  */
 235 struct enum_table {
 236         GHashTable *value_to_quark_set;         /* (value, GQuark GArray) */
 237         struct cds_list_head range_to_quark;    /* (range, GQuark) */
 238         GHashTable *quark_to_range_set;         /* (GQuark, range GArray) */
 239 };
 240
 241 struct declaration_enum {
 242         struct declaration p;
 243         struct declaration_integer *integer_declaration;
 244         struct enum_table table;
 245 };
 246
 247 struct definition_enum {
 248         struct definition p;
 249         struct definition_integer *integer;
 250         struct declaration_enum *declaration;
 251         /* Last GQuark values read. Keeping a reference on the GQuark array. */
 252         GArray *value;
 253 };
 254
 255 enum ctf_string_encoding {
 256         CTF_STRING_UTF8 = 0,
 257         CTF_STRING_ASCII,
 258         CTF_STRING_UNKNOWN,
 259 };
 260
 261 struct declaration_string {
 262         struct declaration p;
 263         enum ctf_string_encoding encoding;
 264 };
 265
 266 struct definition_string {
 267         struct definition p;
 268         struct declaration_string *declaration;
 269         char *value;    /* freed at definition_string teardown */
 270 };
 271
 272 struct declaration_field {
 273         GQuark name;
 274         struct declaration *declaration;
 275 };
 276
 277 struct field {
 278         GQuark name;
 279         struct definition *definition;
 280 };
 281
 282 struct declaration_struct {
 283         struct declaration p;
 284         GHashTable *fields_by_name;     /* Tuples (field name, field index) */
 285         struct declaration_scope *scope;
 286         GArray *fields;                 /* Array of declaration_field */
 287 };
 288
 289 struct definition_struct {
 290         struct definition p;
 291         struct declaration_struct *declaration;
 292         struct definition_scope *scope;
 293         GArray *fields;                 /* Array of struct field */
 294 };
 295
 296 struct declaration_untagged_variant {
 297         struct declaration p;
 298         GHashTable *fields_by_tag;      /* Tuples (field tag, field index) */
 299         struct declaration_scope *scope;
 300         GArray *fields;                 /* Array of declaration_field */
 301 };
 302
 303 struct declaration_variant {
 304         struct declaration p;
 305         struct declaration_untagged_variant *untagged_variant;
 306         GArray *tag_name;               /* Array of GQuark */
 307 };
 308
 309 /* A variant needs to be tagged to be defined. */
 310 struct definition_variant {
 311         struct definition p;
 312         struct declaration_variant *declaration;
 313         struct definition_scope *scope;
 314         struct definition *enum_tag;
 315         GArray *fields;                 /* Array of struct field */
 316         struct field *current_field;    /* Last field read */
 317 };
 318
 319 struct declaration_array {
 320         struct declaration p;
 321         size_t len;
 322         struct declaration *elem;
 323         struct declaration_scope *scope;
 324 };
 325
 326 struct definition_array {
 327         struct definition p;
 328         struct declaration_array *declaration;
 329         struct definition_scope *scope;
 330         struct field current_element;           /* struct field */
 331 };
 332
 333 struct declaration_sequence {
 334         struct declaration p;
 335         struct declaration_integer *len_declaration;
 336         struct declaration *elem;
 337         struct declaration_scope *scope;
 338 };
 339
 340 struct definition_sequence {
 341         struct definition p;
 342         struct declaration_sequence *declaration;
 343         struct definition_scope *scope;
 344         struct definition_integer *len;
 345         struct field current_element;           /* struct field */
 346 };
 347
 348 int register_declaration(GQuark declaration_name,
 349                          struct declaration *declaration,
 350                          struct declaration_scope *scope);
 351 struct declaration *lookup_declaration(GQuark declaration_name,
 352                                        struct declaration_scope *scope);
 353
 354 /*
 355  * Type scopes also contain a separate registry for struct, variant and
 356  * enum types. Those register types rather than type definitions, so
 357  * that a named variant can be declared without specifying its target
 358  * "choice" tag field immediately.
 359  */
 360 int register_struct_declaration(GQuark struct_name,
 361                                 struct declaration_struct *struct_declaration,
 362                                 struct declaration_scope *scope);
 363 struct declaration_struct *
 364         lookup_struct_declaration(GQuark struct_name,
 365                                   struct declaration_scope *scope);
 366 int register_variant_declaration(GQuark variant_name,
 367                           struct declaration_untagged_variant *untagged_variant_declaration,
 368                           struct declaration_scope *scope);
 369 struct declaration_untagged_variant *lookup_variant_declaration(GQuark variant_name,
 370                                          struct declaration_scope *scope);
 371 int register_enum_declaration(GQuark enum_name,
 372                               struct declaration_enum *enum_declaration,
 373                               struct declaration_scope *scope);
 374 struct declaration_enum *
 375         lookup_enum_declaration(GQuark enum_name,
 376                                 struct declaration_scope *scope);
 377
 378 struct declaration_scope *
 379         new_declaration_scope(struct declaration_scope *parent_scope);
 380 void free_declaration_scope(struct declaration_scope *scope);
 381
 382 /*
 383  * field_definition is for field definitions. They are registered into
 384  * definition scopes.
 385  */
 386 struct definition *
 387         lookup_definition(GArray *cur_path,     /* array of GQuark */
 388                           GArray *lookup_path,  /* array of GQuark */
 389                           struct definition_scope *scope);
 390 int register_field_definition(GQuark field_name,
 391                               struct definition *definition,
 392                               struct definition_scope *scope);
 393 struct definition_scope *
 394         new_definition_scope(struct definition_scope *parent_scope,
 395                              GQuark field_name);
 396 void set_dynamic_definition_scope(struct definition *definition,
 397                                   struct definition_scope *scope,
 398                                   const char *root_name);
 399 void free_definition_scope(struct definition_scope *scope);
 400
 401 void declaration_ref(struct declaration *declaration);
 402 void declaration_unref(struct declaration *declaration);
 403
 404 void definition_ref(struct definition *definition);
 405 void definition_unref(struct definition *definition);
 406
 407 struct declaration_integer *integer_declaration_new(size_t len, int byte_order,
 408                                       int signedness, size_t alignment);
 409
 410 /*
 411  * mantissa_len is the length of the number of bytes represented by the mantissa
 412  * (e.g. result of DBL_MANT_DIG). It includes the leading 1.
 413  */
 414 struct declaration_float *float_declaration_new(size_t mantissa_len,
 415                                   size_t exp_len, int byte_order,
 416                                   size_t alignment);
 417
 418 /*
 419  * A GQuark can be translated to/from strings with g_quark_from_string() and
 420  * g_quark_to_string().
 421  */
 422
 423 /*
 424  * Returns a GArray of GQuark or NULL.
 425  * Caller must release the GArray with g_array_unref().
 426  */
 427 GArray *enum_uint_to_quark_set(const struct declaration_enum *enum_declaration,
 428                                uint64_t v);
 429
 430 /*
 431  * Returns a GArray of GQuark or NULL.
 432  * Caller must release the GArray with g_array_unref().
 433  */
 434 GArray *enum_int_to_quark_set(const struct declaration_enum *enum_declaration,
 435                               uint64_t v);
 436
 437 /*
 438  * Returns a GArray of struct enum_range or NULL.
 439  * Callers do _not_ own the returned GArray (and therefore _don't_ need to
 440  * release it).
 441  */
 442 GArray *enum_quark_to_range_set(const struct declaration_enum *enum_declaration,
 443                                 GQuark q);
 444 void enum_signed_insert(struct declaration_enum *enum_declaration,
 445                         int64_t start, int64_t end, GQuark q);
 446 void enum_unsigned_insert(struct declaration_enum *enum_declaration,
 447                           uint64_t start, uint64_t end, GQuark q);
 448 size_t enum_get_nr_enumerators(struct declaration_enum *enum_declaration);
 449
 450 struct declaration_enum *
 451         enum_declaration_new(struct declaration_integer *integer_declaration);
 452
 453 struct declaration_string *
 454         string_declaration_new(enum ctf_string_encoding encoding);
 455
 456 struct declaration_struct *
 457         struct_declaration_new(struct declaration_scope *parent_scope);
 458 void struct_declaration_add_field(struct declaration_struct *struct_declaration,
 459                                   const char *field_name,
 460                                   struct declaration *field_declaration);
 461 /*
 462  * Returns the index of a field within a structure.
 463  */
 464 unsigned long struct_declaration_lookup_field_index(struct declaration_struct *struct_declaration,
 465                                                     GQuark field_name);
 466 /*
 467  * field returned only valid as long as the field structure is not appended to.
 468  */
 469 struct declaration_field *
 470 struct_declaration_get_field_from_index(struct declaration_struct *struct_declaration,
 471                                         unsigned long index);
 472 struct field *
 473 struct_get_field_from_index(struct definition_struct *struct_definition,
 474                             unsigned long index);
 475
 476 /*
 477  * The tag enumeration is validated to ensure that it contains only mappings
 478  * from numeric values to a single tag. Overlapping tag value ranges are
 479  * therefore forbidden.
 480  */
 481 struct declaration_untagged_variant *untagged_variant_declaration_new(
 482                 struct declaration_scope *parent_scope);
 483 struct declaration_variant *variant_declaration_new(struct declaration_untagged_variant *untagged_variant,
 484                 const char *tag);
 485
 486 void untagged_variant_declaration_add_field(struct declaration_untagged_variant *untagged_variant_declaration,
 487                 const char *field_name,
 488                 struct declaration *field_declaration);
 489 struct declaration_field *
 490         untagged_variant_declaration_get_field_from_tag(struct declaration_untagged_variant *untagged_variant_declaration,
 491                 GQuark tag);
 492 /*
 493  * Returns 0 on success, -EPERM on error.
 494  */
 495 int variant_definition_set_tag(struct definition_variant *variant,
 496                                struct definition *enum_tag);
 497 /*
 498  * Returns the field selected by the current tag value.
 499  * field returned only valid as long as the variant structure is not appended
 500  * to.
 501  */
 502 struct field *variant_get_current_field(struct definition_variant *variant);
 503
 504 /*
 505  * elem_declaration passed as parameter now belongs to the array. No
 506  * need to free it explicitly. "len" is the number of elements in the
 507  * array.
 508  */
 509 struct declaration_array *
 510         array_declaration_new(size_t len, struct declaration *elem_declaration,
 511                 struct declaration_scope *parent_scope);
 512
 513 /*
 514  * int_declaration and elem_declaration passed as parameter now belong
 515  * to the sequence. No need to free them explicitly.
 516  */
 517 struct declaration_sequence *
 518         sequence_declaration_new(struct declaration_integer *len_declaration,
 519                 struct declaration *elem_declaration,
 520                 struct declaration_scope *parent_scope);
 521
 522 /*
 523  * in: path (dot separated), out: q (GArray of GQuark)
 524  */
 525 void append_scope_path(const char *path, GArray *q);
 526
 527 #endif /* _BABELTRACE_declarationS_H */