ctf-spec.info revision 1.1.1.1 1 This is ctf-spec.info, produced by makeinfo version 6.8 from
2 ctf-spec.texi.
3
4 Copyright (C) 2021-2022 Free Software Foundation, Inc.
5
6 Permission is granted to copy, distribute and/or modify this document
7 under the terms of the GNU General Public License, Version 3 or any
8 later version published by the Free Software Foundation. A copy of the
9 license is included in the section entitled "GNU General Public
10 License".
11
12 INFO-DIR-SECTION Software development
13 START-INFO-DIR-ENTRY
14 * CTF: (ctf-spec). The CTF file format.
15 END-INFO-DIR-ENTRY
16
17
18 File: ctf-spec.info, Node: Top, Next: Overview, Up: (dir)
19
20 The CTF file format
21 *******************
22
23 This manual describes version 3 of the CTF file format, which is
24 intended to model the C type system in a fashion that C programs can
25 consume at runtime.
26
27 * Menu:
28
29 * Overview::
30 * CTF archive::
31 * CTF dictionaries::
32 * Index::
33
34
35 File: ctf-spec.info, Node: Overview, Next: CTF archive, Prev: Top, Up: Top
36
37 Overview
38 ********
39
40 The CTF file format compactly describes C types and the association
41 between function and data symbols and types: if embedded in ELF objects,
42 it can exploit the ELF string table to reduce duplication further.
43 There is no real concept of namespacing: only top-level types are
44 described, not types scoped to within single functions.
45
46 CTF dictionaries can be "children" of other dictionaries, in a
47 one-level hierarchy: child dictionaries can refer to types in the
48 parent, but the opposite is not sensible (since if you refer to a child
49 type in the parent, the actual type you cited would vary depending on
50 what child was attached). This parent/child definition is recorded in
51 the child, but only as a recommendation: users of the API have to attach
52 parents to children explicitly, and can choose to attach a child to any
53 parent they like, or to none, though doing so might lead to unpleasant
54 consequences like dangling references to types. *Note Type indexes and
55 type IDs::. Type lookups in child dicts that are not associated with a
56 parent at all will fail with 'ECTF_NOPARENT' if a parent type was
57 needed.
58
59 The associated API to generate, merge together, and query this file
60 format will be described in the accompanying 'libctf' manual once it is
61 written. There is no API to modify dictionaries once they've been
62 written out: CTF is a write-once file format. (However, it is always
63 possible to dynamically create a new child dictionary on the fly and
64 attach it to a pre-existing, read-only parent.)
65
66 There are two major pieces to CTF: the "archive" and the
67 "dictionary". Some relatives and ancestors of CTF call dictionaries
68 "containers": the archive format is unique to this variant of CTF. (Much
69 of the source code still uses the old term.)
70
71 The archive file format is a very simple mmappable archive used to
72 group multiple dictionaries together into groups: it is expected to
73 slowly go away and be replaced by other mechanisms, but right now it is
74 an important part of the file format, used to group dictionaries
75 containing types with conflicting definitions in different TUs with the
76 overarching dictionary used to store all other types. (Even when
77 archives go away, the 'libctf' API used to access them will remain, and
78 access the other mechanisms that replace it instead.)
79
80 The CTF dictionary consists of a "preamble", which does not vary
81 between versions of the CTF file format, and a "header" and some number
82 of "sections", which can vary between versions.
83
84 The rest of this specification describes the format of these
85 sections, first for the latest version of CTF, then for all earlier
86 versions supported by 'libctf': the earlier versions are defined in
87 terms of their differences from the next later one. We describe each
88 part of the format first by reproducing the C structure which defines
89 that part, then describing it at greater length in terms of file
90 offsets.
91
92 The description of the file format ends with a description of
93 relevant limits that apply to it. These limits can vary between file
94 format versions.
95
96 This document is quite young, so for now the C code in 'ctf.h' should
97 be presumed correct when this document conflicts with it.
98
99
100 File: ctf-spec.info, Node: CTF archive, Next: CTF dictionaries, Prev: Overview, Up: Top
101
102 1 CTF archives
103 **************
104
105 The CTF archive format maps names to CTF dictionaries. The names may
106 contain any character other than \0, but for now archives containing
107 slashes in the names may not extract correctly. It is possible to
108 insert multiple members with the same name, but these are quite hard to
109 access reliably (you have to iterate through all the members rather than
110 opening by name) so this is not recommended.
111
112 CTF archives are not themselves compressed: the constituent
113 components, CTF dictionaries, can be compressed. (*Note CTF header::).
114
115 CTF archives usually contain a collection of related dictionaries,
116 one parent and many children of that parent. CTF archives can have a
117 member with a "default name", '.ctf' (which can be represented as 'NULL'
118 in the API). If present, this member is usually the parent of all the
119 children, but it is possible for CTF producers to emit parents with
120 different names if they wish (usually for backward- compatibility
121 purposes).
122
123 '.ctf' sections in ELF objects consist of a single CTF dictionary
124 rather than an archive of dictionaries if and only if the section
125 contains no types with identical names but conflicting definitions: if
126 two conflicting definitions exist, the deduplicator will place the type
127 most commonly referred to by other types in the parent and will place
128 the other type in a child named after the translation unit it is found
129 in, and will emit a CTF archive containing both dictionaries instead of
130 a raw dictionary. All types that refer to such conflicting types are
131 also placed in the per-translation-unit child.
132
133 The definition of an archive in 'ctf.h' is as follows:
134
135 struct ctf_archive
136 {
137 uint64_t ctfa_magic;
138 uint64_t ctfa_model;
139 uint64_t ctfa_nfiles;
140 uint64_t ctfa_names;
141 uint64_t ctfa_ctfs;
142 };
143
144 typedef struct ctf_archive_modent
145 {
146 uint64_t name_offset;
147 uint64_t ctf_offset;
148 } ctf_archive_modent_t;
149
150 (Note one irregularity here: the 'ctf_archive_t' is not a typedef to
151 'struct ctf_archive', but a different typedef, private to 'libctf', so
152 that things that are not really archives can be made to appear as if
153 they were.)
154
155 All the above items are always in little-endian byte order,
156 regardless of the machine endianness.
157
158 The archive header has the following fields:
159
160 Offset Name Description
161 ------------------------------------------------------------------------------------------
162 0x00 'uint64_t ctfa_magic' The magic number for archives, 'CTFA_MAGIC':
163 0x8b47f2a4d7623eeb.
164
165 0x08 'uint64_t ctfa_model' The data model for this archive: an arbitrary integer
166 that serves no purpose but to be handed back by the
167 libctf API. *Note Data models::.
168
169 0x10 'uint64_t ctfa_nfiles' The number of CTF dictionaries in this archive.
170
171 0x18 'uint64_t ctfa_names' Offset of the name table, in bytes from the start of
172 the archive. The name table is an array of 'struct
173 ctf_archive_modent_t[ctfa_nfiles]'.
174
175 0x20 'uint64_t ctfa_ctfs' Offset of the CTF table. Each element starts with a
176 'uint64_t' size, followed by a CTF dictionary.
177
178
179 The array pointed to by 'ctfa_names' is an array of entries of
180 'ctf_archive_modent':
181
182 Offset Name Description
183 ---------------------------------------------------------------------------------
184 0x00 'uint64_t name_offset' Offset of this name, in bytes from the start
185 of the archive.
186
187 0x08 'uint64_t ctf_offset' Offset of this CTF dictionary, in bytes from
188 the start of the archive.
189
190
191 The 'ctfa_names' array is sorted into ASCIIbetical order by name
192 (i.e. by the result of dereferencing the 'name_offset').
193
194 The archive file also contains a name table and a table of CTF
195 dictionaries: these are pointed to by the structures above. The name
196 table is a simple strtab which is not required to be sorted; the
197 dictionary array is described above in the entry for 'ctfa_ctfs'.
198
199 The relative order of these various parts is not defined, except that
200 the header naturally always comes first.
201
202
203 File: ctf-spec.info, Node: CTF dictionaries, Next: Index, Prev: CTF archive, Up: Top
204
205 2 CTF dictionaries
206 ******************
207
208 CTF dictionaries consist of a header, starting with a premable, and a
209 number of sections.
210
211 * Menu:
212
213 * CTF Preamble::
214 * CTF header::
215 * The type section::
216 * The symtypetab sections::
217 * The variable section::
218 * The label section::
219 * The string section::
220 * Data models::
221 * Limits of CTF::
222
223
224 File: ctf-spec.info, Node: CTF Preamble, Next: CTF header, Up: CTF dictionaries
225
226 2.1 CTF Preamble
227 ================
228
229 The preamble is the only part of the CTF dictionary whose format cannot
230 vary between versions. It is never compressed. It is correspondingly
231 simple:
232
233 typedef struct ctf_preamble
234 {
235 unsigned short ctp_magic;
236 unsigned char ctp_version;
237 unsigned char ctp_flags;
238 } ctf_preamble_t;
239
240 '#define's are provided under the names 'cth_magic', 'cth_version'
241 and 'cth_flags' to make the fields of the 'ctf_preamble_t' appear to be
242 part of the 'ctf_header_t', so consuming programs rarely need to
243 consider the existence of the preamble as a separate structure.
244
245 Offset Name Description
246 -------------------------------------------------------------------------------
247 0x00 'unsigned short ctp_magic' The magic number for CTF
248 dictionaries, 'CTF_MAGIC': 0xdff2.
249
250 0x02 'unsigned char ctp_version' The version number of this CTF
251 dictionary.
252
253 0x03 'ctp_flags' Flags for this CTF file.
254 *Note CTF file-wide flags::.
255
256 Every element of a dictionary must be naturally aligned unless
257 otherwise specified. (This restriction will be lifted in later
258 versions.)
259
260 CTF dictionaries are stored in the native endianness of the system
261 that generates them: the consumer (e.g., 'libctf') can detect whether to
262 endian-flip a CTF dictionary by inspecting the 'ctp_magic'. (If it
263 appears as 0xf2df, endian-flipping is needed.)
264
265 The version of the CTF dictionary can be determined by inspecting
266 'ctp_version'. The following versions are currently valid, and 'libctf'
267 can read all of them:
268
269 Version Number Description
270 -------------------------------------------------------------------------------------------
271 'CTF_VERSION_1' 1 First version, rare. Very similar to Solaris CTF.
272
273 'CTF_VERSION_1_UPGRADED_3' 2 First version, upgraded to v3 or higher and
274 written out again. Name may change. Very rare.
275
276 'CTF_VERSION_2' 3 Second version, with many range limits lifted.
277
278 'CTF_VERSION_3' 4 Third and current version, documented here.
279
280 This section documents 'CTF_VERSION_3'.
281
282 * Menu:
283
284 * CTF file-wide flags::
285
286
287 File: ctf-spec.info, Node: CTF file-wide flags, Up: CTF Preamble
288
289 2.1.1 CTF file-wide flags
290 -------------------------
291
292 The preamble contains bitflags in its 'ctp_flags' field that describe
293 various file-wide properties. Some of the flags are valid only for
294 particular file-format versions, which means the flags can be used to
295 fix file-format bugs. Consumers that see unknown flags should
296 accordingly assume that the dictionary is not comprehensible, and refuse
297 to open them.
298
299 The following flags are currently defined. Many are bug workarounds,
300 valid only in CTFv3, and will not be valid in any future versions: the
301 same values may be reused for other flags in v4+.
302
303 Flag Versions Value Meaning
304 ---------------------------------------------------------------------------------------
305 'CTF_F_COMPRESS' All 0x1 Compressed with zlib
306 'CTF_F_NEWFUNCINFO' 3 only 0x2 "New-format" func info section.
307 'CTF_F_IDXSORTED' 3+ 0x4 The index section is in sorted order
308 'CTF_F_DYNSTR' 3 only 0x8 The external strtab is in '.dynstr' and the
309 symtab used is '.dynsym'.
310 *Note The string section::
311
312 'CTF_F_NEWFUNCINFO' and 'CTF_F_IDXSORTED' relate to the function info
313 and data object sections. *Note The symtypetab sections::.
314
315 Further flags (and further compression methods) wil be added in
316 future.
317
318
319 File: ctf-spec.info, Node: CTF header, Next: The type section, Prev: CTF Preamble, Up: CTF dictionaries
320
321 2.2 CTF header
322 ==============
323
324 The CTF header is the first part of a CTF dictionary, including the
325 preamble. All parts of it other than the preamble (*note CTF
326 Preamble::) can vary between CTF file versions and are never compressed.
327 It contains things that apply to the dictionary as a whole, and a table
328 of the sections into which the rest of the dictionary is divided. The
329 sections tile the file: each section runs from the offset given until
330 the start of the next section. Only the last section cannot follow this
331 rule, so the header has a length for it instead.
332
333 All section offsets, here and in the rest of the CTF file, are
334 relative to the _end_ of the header. (This is annoyingly different to
335 how offsets in CTF archives are handled.)
336
337 This is the first structure to include offsets into the string table,
338 which are not straight references because CTF dictionaries can include
339 references into the ELF string table to save space, as well as into the
340 string table internal to the CTF dictionary. *Note The string section::
341 for more on these. Offset 0 is always the null string.
342
343 typedef struct ctf_header
344 {
345 ctf_preamble_t cth_preamble;
346 uint32_t cth_parlabel;
347 uint32_t cth_parname;
348 uint32_t cth_cuname;
349 uint32_t cth_lbloff;
350 uint32_t cth_objtoff;
351 uint32_t cth_funcoff;
352 uint32_t cth_objtidxoff;
353 uint32_t cth_funcidxoff;
354 uint32_t cth_varoff;
355 uint32_t cth_typeoff;
356 uint32_t cth_stroff;
357 uint32_t cth_strlen;
358 } ctf_header_t;
359
360 In detail:
361
362 Offset Name Description
363 -----------------------------------------------------------------------------------------------
364 0x00 'ctf_preamble_t cth_preamble' The preamble (conceptually embedded in the header).
365 *Note CTF Preamble::
366
367 0x04 'uint32_t cth_parlabel' The parent label, if deduplication happened against
368 a specific label: a strtab offset.
369 *Note The label section::. Currently unused and
370 always 0, but may be used in future when semantics
371 are attached to the label section.
372
373 0x08 'uint32_t cth_parname' The name of the parent dictionary deduplicated
374 against: a strtab offset. Interpretation is up to
375 the consumer (usually a CTF archive member name).
376 0 (the null string) if this is not a child
377 dictionary.
378
379 0x1c 'uint32_t cth_cuname' The name of the compilation unit, for consumers
380 like GDB that want to know the name of CUs
381 associated with single CUs: a strtab offset. 0 if
382 this dictionary describes types from many CUs.
383
384 0x10 'uint32_t cth_lbloff' The offset of the label section, which tiles the
385 type space into named regions.
386 *Note The label section::.
387
388 0x14 'uint32_t cth_objtoff' The offset of the data object symtypetab section,
389 which maps ELF data symbols to types.
390 *Note The symtypetab sections::.
391
392 0x18 'uint32_t cth_funcoff' The offset of the function info symtypetab section,
393 which maps ELF function symbols to a return type
394 and arg types. *Note The symtypetab sections::.
395
396 0x1c 'uint32_t cth_objtidxoff' The offset of the object index section, which maps
397 ELF object symbols to entries in the data object
398 section. *Note The symtypetab sections::.
399
400 0x20 'uint32_t cth_funcidxoff' The offset of the function info index section,
401 which maps ELF function symbols to entries in the
402 function info section.
403 *Note The symtypetab sections::.
404
405 0x24 'uint32_t cth_varoff' The offset of the variable section, which maps
406 string names to types.
407 *Note The variable section::.
408
409 0x28 'uint32_t cth_typeoff' The offset of the type section, the core of CTF,
410 which describes types using variable-length array
411 elements. *Note The type section::.
412
413 0x2c 'uint32_t cth_stroff' The offset of the string section.
414 *Note The string section::.
415
416 0x30 'uint32_t cth_strlen' The length of the string section (not an offset!).
417 The CTF file ends at this point.
418
419
420 Everything from this point on (until the end of the file at
421 'cth_stroff' + 'cth_strlen') is compressed with zlib if 'CTF_F_COMPRESS'
422 is set in the preamble's 'ctp_flags'.
423
424
425 File: ctf-spec.info, Node: The type section, Next: The symtypetab sections, Prev: CTF header, Up: CTF dictionaries
426
427 2.3 The type section
428 ====================
429
430 This section is the most important section in CTF, describing all the
431 top-level types in the program. It consists of an array of type
432 structures, each of which describes a type of some "kind": each kind of
433 type has some amount of variable-length data associated with it (some
434 kinds have none). The amount of variable-length data associated with a
435 given type can be determined by inspecting the type, so the reading code
436 can walk through the types in sequence at opening time.
437
438 Each type structure is one of a set of overlapping structures in a
439 discriminated union of sorts: the variable-length data for each type
440 immediately follows the type's type structure. Here's the largest of
441 the overlapping structures, which is only needed for huge types and so
442 is very rarely seen:
443
444 typedef struct ctf_type
445 {
446 uint32_t ctt_name;
447 uint32_t ctt_info;
448 __extension__
449 union
450 {
451 uint32_t ctt_size;
452 uint32_t ctt_type;
453 };
454 uint32_t ctt_lsizehi;
455 uint32_t ctt_lsizelo;
456 } ctf_type_t;
457
458 Here's the much more common smaller form:
459
460 typedef struct ctf_stype
461 {
462 uint32_t ctt_name;
463 uint32_t ctt_info;
464 __extension__
465 union
466 {
467 uint32_t ctt_size;
468 uint32_t ctt_type;
469 };
470 } ctf_type_t;
471
472 If 'ctt_size' is the #define 'CTF_LSIZE_SENT', 0xffffffff, this type
473 is described by a 'ctf_type_t': otherwise, a 'ctf_stype_t'.
474
475 Here's what the fields mean:
476
477 Offset Name Description
478 -----------------------------------------------------------------------------------------------------
479 0x00 'uint32_t ctt_name' Strtab offset of the type name, if any (0 if none).
480
481 0x04 'uint32_t ctt_info' The "info word", containing information on the kind
482 of this type, its variable-length data and whether
483 it is visible to name lookup. See
484 *Note The info word::.
485
486 0x08 'uint32_t ctt_size' The size of this type, if this type is of a kind for
487 which a size needs to be recorded (constant-size
488 types don't need one). If this is 'CTF_LSIZE_SENT',
489 this type is a huge type described by 'ctf_type_t'.
490
491 0x08 'uint32_t ctt_type' The type this type refers to, if this type is of a
492 kind which refers to other types (like a pointer).
493 All such types are fixed-size, and no types that are
494 variable-size refer to other types, so 'ctt_size'
495 and 'ctt_type' overlap. All type kinds that use
496 'ctt_type' are described by 'ctf_stype_t', not
497 'ctf_type_t'. *Note Type indexes and type IDs::.
498
499 0x0c ('ctf_type_t' 'uint32_t ctt_lsizehi' The high 32 bits of the size of a very large type.
500 only) The 'CTF_TYPE_LSIZE' macro can be used to get a
501 64-bit size out of this field and the next one.
502 'CTF_SIZE_TO_LSIZE_HI' splits the 'ctt_lsizehi' out
503 of it again.
504
505 0x10 ('ctf_type_t' 'uint32_t ctt_lsizelo' The low 32 bits of the size of a very large type.
506 only) 'CTF_SIZE_TO_LSIZE_LO' splits the 'ctt_lsizelo' out
507 of a 64-bit size.
508
509 Two aspects of this need further explanation: the info word, and what
510 exactly a type ID is and how you determine it. (Information on the
511 various type-kind- dependent things, like whether 'ctt_size' or
512 'ctt_type' is used, is described in the section devoted to each kind.)
513
514 * Menu:
515
516 * The info word::
517 * Type indexes and type IDs::
518 * Type kinds::
519 * Integer types::
520 * Floating-point types::
521 * Slices::
522 * Pointers typedefs and cvr-quals::
523 * Arrays::
524 * Function pointers::
525 * Enums::
526 * Structs and unions::
527 * Forward declarations::
528
529
530 File: ctf-spec.info, Node: The info word, Next: Type indexes and type IDs, Up: The type section
531
532 2.3.1 The info word, ctt_info
533 -----------------------------
534
535 The info word is a bitfield split into three parts. From MSB to LSB:
536
537 Bit offset Name Description
538 ------------------------------------------------------------------------------------------
539 26-31 'kind' Type kind: *note Type kinds::.
540
541 25 'isroot' 1 if this type is visible to name lookup
542
543 0-24 'vlen' Length of variable-length data for this type (some kinds only).
544 The variable-length data directly follows the 'ctf_type_t' or
545 'ctf_stype_t'. This is a kind-dependent array length value,
546 not a length in bytes. Some kinds have no variable-length
547 data, or fixed-size variable-length data, and do not use this
548 value.
549
550 The most mysterious of these is undoubtedly 'isroot'. This indicates
551 whether types with names (nonzero 'ctt_name') are visible to name
552 lookup: if zero, this type is considered a "non-root type" and you can't
553 look it up by name at all. Multiple types with the same name in the
554 same C namespace (struct, union, enum, other) can exist in a single
555 dictionary, but only one of them may have a nonzero value for 'isroot'.
556 'libctf' validates this at open time and refuses to open dictionaries
557 that violate this constraint.
558
559 Historically, this feature was introduced for the encoding of
560 bitfields (*note Integer types::): for instance, int bitfields will all
561 be named 'int' with different widths or offsets, but only the full-width
562 one at offset zero is wanted when you look up the type named 'int'.
563 With the introduction of slices (*note Slices::) as a more general
564 bitfield encoding mechanism, this is less important, but we still use
565 non-root types to handle conflicts if the linker API is used to fuse
566 multiple translation units into one dictionary and those translation
567 units contain types with the same name and conflicting definitions. (We
568 do not discuss this further here, because the linker never does this:
569 only specialized type mergers do, like that used for the Linux kernel.
570 The libctf documentation will describe this in more detail.)
571
572 The 'CTF_TYPE_INFO' macro can be used to compose an info word from a
573 'kind', 'isroot', and 'vlen'; 'CTF_V2_INFO_KIND', 'CTF_V2_INFO_ISROOT'
574 and 'CTF_V2_INFO_VLEN' pick it apart again.
575
576
577 File: ctf-spec.info, Node: Type indexes and type IDs, Next: Type kinds, Prev: The info word, Up: The type section
578
579 2.3.2 Type indexes and type IDs
580 -------------------------------
581
582 Types are referred to within the CTF file via "type IDs". A type ID is
583 a number from 0 to 2^32, from a space divided in half. Types 2^31-1 and
584 below are in the "parent range": these IDs are used for dictionaries
585 that have not had any other dictionary 'ctf_import'ed into it as a
586 parent. Both completely standalone dictionaries and parent dictionaries
587 with children hanging off them have types in this range. Types 2^31 and
588 above are in the "child range": only types in child dictionaries are in
589 this range.
590
591 These IDs appear in 'ctf_type_t.ctt_type' (*note The type section::),
592 but the types themselves have no visible ID: quite intentionally,
593 because adding an ID uses space, and every ID is different so they don't
594 compress well. The IDs are implicit: at open time, the consumer walks
595 through the entire type section and counts the types in the type
596 section. The type section is an array of variable-length elements, so
597 each entry could be considered as having an index, starting from 1. We
598 count these indexes and associate each with its corresponding
599 'ctf_type_t' or 'ctf_stype_t'.
600
601 Lookups of types with IDs in the parent space look in the parent
602 dictionary if this dictionary has one associated with it; lookups of
603 types with IDs in the child space error out if the dictionary does not
604 have a parent, and otherwise convert the ID into an index by shaving off
605 the top bit and look up the index in the child.
606
607 These properties mean that the same dictionary can be used as a
608 parent of child dictionaries and can also be used directly with no
609 children at all, but a dictionary created as a child dictionary must
610 always be associated with a parent -- usually, the same parent --
611 because its references to its own types have the high bit turned on and
612 this is only flipped off again if this is a child dictionary. (This is
613 not a problem, because if you _don't_ associate the child with a parent,
614 any references within it to its parent types will fail, and there are
615 almost certain to be many such references, or why is it a child at all?)
616
617 This does mean that consumers should keep a close eye on the
618 distinction between type IDs and type indexes: if you mix them up,
619 everything will appear to work as long as you're only using parent
620 dictionaries or standalone dictionaries, but as soon as you start using
621 children, everything will fail horribly.
622
623 Type index zero, and type ID zero, are used to indicate that this
624 type cannot be represented in CTF as currently constituted: they are
625 emitted by the compiler, but all type chains that terminate in the
626 unknown type are erased at link time (structure fields that use them
627 just vanish, etc). So you will probably never see a use of type zero
628 outside the symtypetab sections, where they serve as sentinels of sorts,
629 to indicate symbols with no associated type.
630
631 The macros 'CTF_V2_TYPE_TO_INDEX' and 'CTF_V2_INDEX_TO_TYPE' may help
632 in translation between types and indexes: 'CTF_V2_TYPE_ISPARENT' and
633 'CTF_V2_TYPE_ISCHILD' can be used to tell whether a given ID is in the
634 parent or child range.
635
636 It is quite possible and indeed common for type IDs to point forward
637 in the dictionary, as well as backward.
638
639
640 File: ctf-spec.info, Node: Type kinds, Next: Integer types, Prev: Type indexes and type IDs, Up: The type section
641
642 2.3.3 Type kinds
643 ----------------
644
645 Every type in CTF is of some "kind". Each kind is some variety of C
646 type: all structures are a single kind, as are all unions, all pointers,
647 all arrays, all integers regardless of their bitfield width, etc. The
648 kind of a type is given in the 'kind' field of the 'ctt_info' word
649 (*note The info word::).
650
651 The space of type kinds is only a quarter full so far, so there is
652 plenty of room for expansion. It is likely that in future versions of
653 the file format, types with smaller kinds will be more efficiently
654 encoded than types with larger kinds, so their numerical value will
655 actually start to matter in future. (So these IDs will probably change
656 their numerical values in a later release of this format, to move more
657 frequently-used kinds like structures and cv-quals towards the top of
658 the space, and move rarely-used kinds like integers downwards. Yes,
659 integers are rare: how many kinds of 'int' are there in a program?
660 They're just very frequently _referenced_.)
661
662 Here's the set of kinds so far. Each kind has a '#define' associated
663 with it, also given here.
664
665 Kind Macro Purpose
666 ----------------------------------------------------------------------------------------
667 0 'CTF_K_UNKNOWN' Indicates a type that cannot be represented in CTF, or that
668 is being skipped. It is very similar to type ID 0, except
669 that you can have _multiple_, distinct types of kind
670 'CTF_K_UNKNOWN'.
671
672 1 'CTF_K_INTEGER' An integer type. *Note Integer types::.
673
674 2 'CTF_K_FLOAT' A floating-point type. *Note Floating-point types::.
675
676 3 'CTF_K_POINTER' A pointer. *Note Pointers typedefs and cvr-quals::.
677
678 4 'CTF_K_ARRAY' An array. *Note Arrays::.
679
680 5 'CTF_K_FUNCTION' A function pointer. *Note Function pointers::.
681
682 6 'CTF_K_STRUCT' A structure. *Note Structs and unions::.
683
684 7 'CTF_K_UNION' A union. *Note Structs and unions::.
685
686 8 'CTF_K_ENUM' An enumerated type. *Note Enums::.
687
688 9 'CTF_K_FORWARD' A forward. *Note Forward declarations::.
689
690 10 'CTF_K_TYPEDEF' A typedef. *Note Pointers typedefs and cvr-quals::.
691
692 11 'CTF_K_VOLATILE' A volatile-qualified type.
693 *Note Pointers typedefs and cvr-quals::.
694
695 12 'CTF_K_CONST' A const-qualified type.
696 *Note Pointers typedefs and cvr-quals::.
697
698 13 'CTF_K_RESTRICT' A restrict-qualified type.
699 *Note Pointers typedefs and cvr-quals::.
700
701 14 'CTF_K_SLICE' A slice, a change of the bit-width or offset of some other
702 type. *Note Slices::.
703
704 Now we cover all type kinds in turn. Some are more complicated than
705 others.
706
707
708 File: ctf-spec.info, Node: Integer types, Next: Floating-point types, Prev: Type kinds, Up: The type section
709
710 2.3.4 Integer types
711 -------------------
712
713 Integral types are all represented as types of kind 'CTF_K_INTEGER'.
714 These types fill out 'ctt_size' in the 'ctf_stype_t' with the size in
715 bytes of the integral type in question. They are always represented by
716 'ctf_stype_t', never 'ctf_type_t'. Their variable-length data is one
717 'uint32_t' in length: 'vlen' in the info word should be disregarded and
718 is always zero.
719
720 The variable-length data for integers has multiple items packed into
721 it much like the info word does.
722
723 Bit offset Name Description
724 -----------------------------------------------------------------------------------
725 24-31 Encoding The desired display representation of this integer. You
726 can extract this field with the 'CTF_INT_ENCODING'
727 macro. See below.
728
729 16-23 Offset The offset of this integral type in bits from the start
730 of its enclosing structure field, adjusted for
731 endianness: *note Structs and unions::. You can extract
732 this field with the 'CTF_INT_OFFSET' macro.
733
734 0-15 Bit-width The width of this integral type in bits. You can
735 extract this field with the 'CTF_INT_BITS' macro.
736
737 If you choose, bitfields can be represented using the things above as
738 a sort of integral type with the 'isroot' bit flipped off and the offset
739 and bits values set in the vlen word: you can populate it with the
740 'CTF_INT_DATA' macro. (But it may be more convenient to represent them
741 using slices of a full-width integer: *note Slices::.)
742
743 Integers that are bitfields usually have a 'ctt_size' rounded up to
744 the nearest power of two in bytes, for natural alignment (e.g. a 17-bit
745 integer would have a 'ctt_size' of 4). However, not all types are
746 naturally aligned on all architectures: packed structures may in theory
747 use integral bitfields with different 'ctt_size', though this is rarely
748 observed.
749
750 The "encoding" for integers is a bit-field comprised of the values
751 below, which consumers can use to decide how to display values of this
752 type:
753
754 Offset Name Description
755 --------------------------------------------------------------------------------------------------------
756 0x01 'CTF_INT_SIGNED' If set, this is a signed int: if false, unsigned.
757
758 0x02 'CTF_INT_CHAR' If set, this is a char type. It is platform-dependent whether unadorned
759 'char' is signed or not: the 'CTF_CHAR' macro produces an integral type
760 suitable for the definition of 'char' on this platform.
761
762 0x04 'CTF_INT_BOOL' If set, this is a boolean type. (It is theoretically possible to turn
763 this and 'CTF_INT_CHAR' on at the same time, but it is not clear what
764 this would mean.)
765
766 0x08 'CTF_INT_VARARGS' If set, this is a varargs-promoted value in a K&R function definition.
767 This is not currently produced or consumed by anything that we know of:
768 it is set aside for future use.
769
770 The GCC "'Complex int'" and fixed-point extensions are not yet
771 supported: references to such types will be emitted as type 0.
772
773
774 File: ctf-spec.info, Node: Floating-point types, Next: Slices, Prev: Integer types, Up: The type section
775
776 2.3.5 Floating-point types
777 --------------------------
778
779 Floating-point types are all represented as types of kind 'CTF_K_FLOAT'.
780 Like integers, These types fill out 'ctt_size' in the 'ctf_stype_t' with
781 the size in bytes of the floating-point type in question. They are
782 always represented by 'ctf_stype_t', never 'ctf_type_t'.
783
784 This part of CTF shows many rough edges in the more obscure corners
785 of floating-point handling, and is likely to change in format v4.
786
787 The variable-length data for floats has multiple items packed into it
788 just like integers do:
789
790 Bit offset Name Description
791 -------------------------------------------------------------------------------------------
792 24-31 Encoding The desired display representation of this float. You can
793 extract this field with the 'CTF_FP_ENCODING' macro. See below.
794
795 16-23 Offset The offset of this floating-point type in bits from the start of
796 its enclosing structure field, adjusted for endianness:
797 *note Structs and unions::. You can extract this field with the
798 'CTF_FP_OFFSET' macro.
799
800 0-15 Bit-width The width of this floating-point type in bits. You can extract
801 this field with the 'CTF_FP_BITS' macro.
802
803 The purpose of the floating-point offset and bit-width is somewhat
804 opaque, since there are no such things as floating-point bitfields in C:
805 the bit-width should be filled out with the full width of the type in
806 bits, and the offset should always be zero. It is likely that these
807 fields will go away in the future. As with integers, you can use
808 'CTF_FP_DATA' to assemble one of these vlen items from its component
809 parts.
810
811 The "encoding" for floats is not a bitfield but a simple value
812 indicating the display representation. Many of these are unused, relate
813 to Solaris-specific compiler extensions, and will be recycled in future:
814 some are unused and will become used in future.
815
816 Offset Name Description
817 ----------------------------------------------------------------------------------------------
818 1 'CTF_FP_SINGLE' This is a single-precision IEEE 754 'float'.
819 2 'CTF_FP_DOUBLE' This is a double-precision IEEE 754 'double'.
820 3 'CTF_FP_CPLX' This is a 'Complex float'.
821 4 'CTF_FP_DCPLX' This is a 'Complex double'.
822 5 'CTF_FP_LDCPLX' This is a 'Complex long double'.
823 6 'CTF_FP_LDOUBLE' This is a 'long double'.
824 7 'CTF_FP_INTRVL' This is a 'float' interval type, a Solaris-specific extension.
825 Unused: will be recycled.
826 8 'CTF_FP_DINTRVL' This is a 'double' interval type, a Solaris-specific
827 extension. Unused: will be recycled.
828 9 'CTF_FP_LDINTRVL' This is a 'long double' interval type, a Solaris-specific
829 extension. Unused: will be recycled.
830 10 'CTF_FP_IMAGRY' This is a the imaginary part of a 'Complex float'. Not
831 currently generated. May change.
832 11 'CTF_FP_DIMAGRY' This is a the imaginary part of a 'Complex double'. Not
833 currently generated. May change.
834 12 'CTF_FP_LDIMAGRY' This is a the imaginary part of a 'Complex long double'. Not
835 currently generated. May change.
836
837 The use of the complex floating-point encodings is obscure: it is
838 possible that 'CTF_FP_CPLX' is meant to be used for only the real part
839 of complex types, and 'CTF_FP_IMAGRY' et al for the imaginary part - but
840 for now, we are emitting 'CTF_FP_CPLX' to cover the entire type, with no
841 way to get at its constituent parts. There appear to be no uses of
842 these encodings anywhere, so they are quite likely to change
843 incompatibly in future.
844
845
846 File: ctf-spec.info, Node: Slices, Next: Pointers typedefs and cvr-quals, Prev: Floating-point types, Up: The type section
847
848 2.3.6 Slices
849 ------------
850
851 Slices, with kind 'CTF_K_SLICE', are an unusual CTF construct: they do
852 not directly correspond to any C type, but are a way to model other
853 types in a more convenient fashion for CTF generators.
854
855 A slice is like a pointer or other reference type in that they are
856 always represented by 'ctf_stype_t': but unlike pointers and other
857 reference types, they populate the 'ctt_size' field just like integral
858 types do, and come with an attached encoding and transform the encoding
859 of the underlying type. The underlying type is described in the
860 variable-length data, similarly to structure and union fields: see
861 below. Requests for the type size should also chase down to the
862 referenced type.
863
864 Slices are always nameless: 'ctt_name' is always zero for them.
865
866 (The 'libctf' API behaviour is unusual as well, and justifies the
867 existence of slices: 'ctf_type_kind' never returns 'CTF_K_SLICE' but
868 always the underlying type kind, so that consumers never need to know
869 about slices: they can tell if an apparent integer is actually a slice
870 if they need to by calling 'ctf_type_reference', which will uniquely
871 return the underlying integral type rather than erroring out with
872 'ECTF_NOTREF' if this is actually a slice. So slices act just like an
873 integer with an encoding, but more closely mirror DWARF and other
874 debugging information formats by allowing CTF file creators to represent
875 a bitfield as a slice of an underlying integral type.)
876
877 The vlen in the info word for a slice should be ignored and is always
878 zero. The variable-length data for a slice is a single 'ctf_slice_t':
879
880 typedef struct ctf_slice
881 {
882 uint32_t cts_type;
883 unsigned short cts_offset;
884 unsigned short cts_bits;
885 } ctf_slice_t;
886
887 Offset Name Description
888 ----------------------------------------------------------------------------------------
889 0x0 'uint32_t cts_type' The type this slice is a slice of. Must be an
890 integral type (or a floating-point type, but
891 this nonsensical option will go away in v4.)
892
893 0x4 'unsigned short cts_offset' The offset of this integral type in bits from
894 the start of its enclosing structure field,
895 adjusted for endianness:
896 *note Structs and unions::. Identical
897 semantics to the 'CTF_INT_OFFSET' field:
898 *note Integer types::. This field is much too
899 long, because the maximum possible offset of
900 an integral type would easily fit in a char:
901 this field is bigger just for the sake of
902 alignment. This will change in v4.
903
904 0x6 'unsigned short cts_bits' The bit-width of this integral type.
905 Identical semantics to the 'CTF_INT_BITS'
906 field: *note Integer types::. As above, this
907 field is really too large and will shrink in
908 v4.
909
910
911 File: ctf-spec.info, Node: Pointers typedefs and cvr-quals, Next: Arrays, Prev: Slices, Up: The type section
912
913 2.3.7 Pointers, typedefs, and cvr-quals
914 ---------------------------------------
915
916 Pointers, 'typedef's, and 'const', 'volatile' and 'restrict' qualifiers
917 are represented identically except for their type kind (though they may
918 be treated differently by consuming libraries like 'libctf', since
919 pointers affect assignment-compatibility in ways cvr-quals do not, and
920 they may have different alignment requirements, etc).
921
922 All of these are represented by 'ctf_stype_t', have no variable data
923 at all, and populate 'ctt_type' with the type ID of the type they point
924 to. These types can stack: a 'CTF_K_RESTRICT' can point to a
925 'CTF_K_CONST' which can point to a 'CTF_K_POINTER' etc.
926
927 They are all unnamed: 'ctt_name' is 0.
928
929 The size of 'CTF_K_POINTER' is derived from the data model (*note
930 Data models::), i.e. in practice, from the target machine ABI, and is
931 not explicitly represented. The size of other kinds in this set should
932 be determined by chasing ctf_types as necessary until a
933 non-typedef/const/volatile/restrict is found, and using that.
934
935
936 File: ctf-spec.info, Node: Arrays, Next: Function pointers, Prev: Pointers typedefs and cvr-quals, Up: The type section
937
938 2.3.8 Arrays
939 ------------
940
941 Arrays are encoded as types of kind 'CTF_K_ARRAY' in a 'ctf_stype_t'.
942 Both size and kind for arrays are zero. The variable-length data is a
943 'ctf_array_t': 'vlen' in the info word should be disregarded and is
944 always zero.
945
946 typedef struct ctf_array
947 {
948 uint32_t cta_contents;
949 uint32_t cta_index;
950 uint32_t cta_nelems;
951 } ctf_array_t;
952
953 Offset Name Description
954 ----------------------------------------------------------------------------------------
955 0x0 'uint32_t cta_contents' The type of the array elements: a type ID.
956
957 0x4 'uint32_t cta_index' The type of the array index: a type ID of an
958 integral type. If this is a variable-length
959 array, the index type ID will be 0 (but the
960 actual index type of this array is probably
961 'int'). Probably redundant and may be
962 dropped in v4.
963
964 0x8 'uint32_t cta_nelems' The number of array elements. 0 for VLAs,
965 and also for the historical variety of VLA
966 which has explicit zero dimensions (which
967 will have a nonzero 'cta_index'.)
968
969 The size of an array can be computed by simple multiplication of the
970 size of the 'cta_contents' type by the 'cta_nelems'.
971
972
973 File: ctf-spec.info, Node: Function pointers, Next: Enums, Prev: Arrays, Up: The type section
974
975 2.3.9 Function pointers
976 -----------------------
977
978 Function pointers are explicitly represented in the CTF type section by
979 a type of kind 'CTF_K_FUNCTION', always encoded with a 'ctf_stype_t'.
980 The 'ctt_type' is the function return type ID. The 'vlen' in the info
981 word is the number of arguments, each of which is a type ID, a
982 'uint32_t': if the last argument is 0, this is a varargs function and
983 the number of arguments is one less than indicated by the vlen.
984
985 If the number of arguments is odd, a single 'uint32_t' of padding is
986 inserted to maintain alignment.
987
988
989 File: ctf-spec.info, Node: Enums, Next: Structs and unions, Prev: Function pointers, Up: The type section
990
991 2.3.10 Enums
992 ------------
993
994 Enumerated types are represented as types of kind 'CTF_K_ENUM' in a
995 'ctf_stype_t'. The 'ctt_size' is always the size of an int from the
996 data model (enum bitfields are implemented via slices). The 'vlen' is a
997 count of enumerations, each of which is represented by a 'ctf_enum_t' in
998 the vlen:
999
1000 typedef struct ctf_enum
1001 {
1002 uint32_t cte_name;
1003 int32_t cte_value;
1004 } ctf_enum_t;
1005
1006 Offset Name Description
1007 ------------------------------------------------------------------------
1008 0x0 'uint32_t cte_name' Strtab offset of the enumeration name.
1009 Must not be 0.
1010
1011 0x4 'int32_t cte_value' The enumeration value.
1012
1013
1014 Enumeration values larger than 2^32 are not yet supported and are
1015 omitted from the enumeration. (v4 will lift this restriction by
1016 encoding the value differently.)
1017
1018 Forward declarations of enums are not implemented with this kind:
1019 *note Forward declarations::.
1020
1021 Enumerated type names, as usual in C, go into their own namespace,
1022 and do not conflict with non-enums, structs, or unions with the same
1023 name.
1024
1025
1026 File: ctf-spec.info, Node: Structs and unions, Next: Forward declarations, Prev: Enums, Up: The type section
1027
1028 2.3.11 Structs and unions
1029 -------------------------
1030
1031 Structures and unions are represnted as types of kind 'CTF_K_STRUCT' and
1032 'CTF_K_UNION': their representation is otherwise identical, and it is
1033 perfectly allowed for "structs" to contain overlapping fields etc, so we
1034 will treat them together for the rest of this section.
1035
1036 They fill out 'ctt_size', and use 'ctf_type_t' in preference to
1037 'ctf_stype_t' if the structure size is greater than 'CTF_MAX_SIZE'
1038 (0xfffffffe).
1039
1040 The vlen for structures and unions is a count of structure fields,
1041 but the type used to represent a structure field (and thus the size of
1042 the variable-length array element representing the type) depends on the
1043 size of the structure: truly huge structures, greater than
1044 'CTF_LSTRUCT_THRESH' bytes in length, use a different type.
1045 ('CTF_LSTRUCT_THRESH' is 536870912, so such structures are vanishingly
1046 rare: in v4, this representation will change somewhat for greater
1047 compactness. It's inherited from v1, where the limits were much lower.)
1048
1049 Most structures can get away with using 'ctf_member_t':
1050
1051 typedef struct ctf_member_v2
1052 {
1053 uint32_t ctm_name;
1054 uint32_t ctm_offset;
1055 uint32_t ctm_type;
1056 } ctf_member_t;
1057
1058 Huge structures that are represented by 'ctf_type_t' rather than
1059 'ctf_stype_t' have to use 'ctf_lmember_t', which splits the offset as
1060 'ctf_type_t' splits the size:
1061
1062 typedef struct ctf_lmember_v2
1063 {
1064 uint32_t ctlm_name;
1065 uint32_t ctlm_offsethi;
1066 uint32_t ctlm_type;
1067 uint32_t ctlm_offsetlo;
1068 } ctf_lmember_t;
1069
1070 Here's what the fields of 'ctf_member' mean:
1071
1072 Offset Name Description
1073 ---------------------------------------------------------------------------------------------------------
1074 0x00 'uint32_t ctm_name' Strtab offset of the field name.
1075
1076 0x04 'uint32_t ctm_offset' The offset of this field _in bits_. (Usually, for bitfields, this is
1077 machine-word-aligned and the individual field has an offset in bits,
1078 but the format allows for the offset to be encoded in bits here.)
1079
1080 0x08 'uint32_t ctm_type' The type ID of the type of the field.
1081
1082 Here's what the fields of the very similar 'ctf_lmember' mean:
1083
1084 Offset Name Description
1085 ------------------------------------------------------------------------------------------------------------
1086 0x00 'uint32_t ctlm_name' Strtab offset of the field name.
1087
1088 0x04 'uint32_t ctlm_offsethi' The high 32 bits of the offset of this field in bits.
1089
1090 0x08 'uint32_t ctlm_type' The type ID of the type of the field.
1091
1092 0x0c 'uint32_t ctlm_offsetlo' The low 32 bits of the offset of this field in bits.
1093
1094 Macros 'CTF_LMEM_OFFSET', 'CTF_OFFSET_TO_LMEMHI' and
1095 'CTF_OFFSET_TO_LMEMLO' serve to extract and install the values of the
1096 'ctlm_offset' fields, much as with the split size fields in
1097 'ctf_type_t'.
1098
1099 Unnamed structure and union fields are simply implemented by
1100 collapsing the unnamed field's members into the containing structure or
1101 union: this does mean that a structure containing an unnamed union can
1102 end up being a "structure" with multiple members at the same offset. (A
1103 future format revision may collapse 'CTF_K_STRUCT' and 'CTF_K_UNION'
1104 into the same kind and decide among them based on whether their members
1105 do in fact overlap.)
1106
1107 Structure and union type names, as usual in C, go into their own
1108 namespace, just as enum type names do.
1109
1110 Forward declarations of structures and unions are not implemented
1111 with this kind: *note Forward declarations::.
1112
1113
1114 File: ctf-spec.info, Node: Forward declarations, Prev: Structs and unions, Up: The type section
1115
1116 2.3.12 Forward declarations
1117 ---------------------------
1118
1119 When the compiler encounters a forward declaration of a struct, union,
1120 or enum, it emits a type of kind 'CTF_K_FORWARD'. If it later
1121 encounters a non- forward declaration of the same thing, it marks the
1122 forward as non-root-visible: before link time, therefore,
1123 non-root-visible forwards indicate that a non-forward is coming.
1124
1125 After link time, forwards are fused with their corresponding
1126 non-forwards by the deduplicator where possible. They are kept if there
1127 is no non-forward definition (maybe it's not visible from any TU at all)
1128 or if 'multiple' conflicting structures with the same name might match
1129 it. Otherwise, all other forwards are converted to structures, unions,
1130 or enums as appropriate, even across TUs if only one structure could
1131 correspond to the forward (after all, all types across all TUs land in
1132 the same dictionary unless they conflict, so promoting forwards to their
1133 concrete type seems most helpful).
1134
1135 A forward has a rather strange representation: it is encoded with a
1136 'ctf_stype_t' but the 'ctt_type' is populated not with a type (if it's a
1137 forward, we don't have an underlying type yet: if we did, we'd have
1138 promoted it and this wouldn't be a forward any more) but with the 'kind'
1139 of the forward. This means that we can distinguish forwards to structs,
1140 enums and unions reliably and ensure they land in the appropriate
1141 namespace even before the actual struct, union or enum is found.
1142
1143
1144 File: ctf-spec.info, Node: The symtypetab sections, Next: The variable section, Prev: The type section, Up: CTF dictionaries
1145
1146 2.4 The symtypetab sections
1147 ===========================
1148
1149 These are two very simple sections with identical formats, used by
1150 consumers to map from ELF function and data symbols directly to their
1151 types. So they are usually populated only in CTF sections that are
1152 embedded in ELF objects.
1153
1154 Their format is very simple: an array of type IDs. Which symbol each
1155 type ID corresponds to depends on whether the optional _index section_
1156 associated with this symtypetab section has any content.
1157
1158 If the index section is nonempty, it is an array of 'uint32_t' string
1159 table offsets, each giving the name of the symbol whose type is at the
1160 same offset in the corresponding non-index section: users can look up
1161 symbols in such a table by name. The index section and corresponding
1162 symtypetab section is usually ASCIIbetically sorted (indicated by the
1163 'CTF_F_IDXSORTED' flag in the header): if it's sorted, it can be
1164 bsearched for a symbol name rather than having to use a slower linear
1165 search.
1166
1167 If the data object index section is empty, the entries in the data
1168 object and function info sections are associated 1:1 with ELF symbols of
1169 type 'STT_OBJECT' (for data object) or 'STT_FUNC' (for function info)
1170 with a nonzero value: the linker shuffles the symtypetab sections to
1171 correspond with the order of the symbols in the ELF file. Symbols with
1172 no name, undefined symbols and symbols named "'_START_'" and "'_END_'"
1173 are skipped and never appear in either section. Symbols that have no
1174 corresponding type are represented by type ID 0. The section may have
1175 fewer entries than the symbol table, in which case no later entries have
1176 associated types. This format is more compact than an indexed form if
1177 most entries have types (since there is no need to record any symbol
1178 names), but if the producer and consumer disagree even slightly about
1179 which symbols are omitted, the types of all further symbols will be
1180 wrong!
1181
1182 The compiler always emits indexed symtypetab tables, because there is
1183 no symbol table yet. The linker will always have to read them all in
1184 and always works through them from start to end, so there is no benefit
1185 having the compiler sort them either. The linker (actually, 'libctf''s
1186 linking machinery) will automatically sort unsorted indexed sections,
1187 and convert indexed sections that contain a lot of pads into the more
1188 compact, unindexed form.
1189
1190 If child dicts are in use, only symbols that use types actually
1191 mentioned in the child appear in the child's symtypetab: symbols that
1192 use only types in the parent appear in the parent's symtypetab instead.
1193 So the child's symtypetab will almost always be very sparse, and thus
1194 will usually use the indexed form even in fully linked objects. (It is,
1195 of course, impossible for symbols to exist that use types from multiple
1196 child dicts at once, since it's impossible to declare a function in C
1197 that uses types that are only visible in two different, disjoint
1198 translation units.)
1199
1200
1201 File: ctf-spec.info, Node: The variable section, Next: The label section, Prev: The symtypetab sections, Up: CTF dictionaries
1202
1203 2.5 The variable section
1204 ========================
1205
1206 The variable section is a simple array mapping names (strtab entries) to
1207 type IDs, intended to provide a replacement for the data object section
1208 in dynamic situations in which there is no static ELF strtab but the
1209 consumer instead hands back names. The section is sorted into
1210 ASCIIbetical order by name for rapid lookup, like the CTF archive name
1211 table.
1212
1213 The section is an array of these structures:
1214
1215 typedef struct ctf_varent
1216 {
1217 uint32_t ctv_name;
1218 uint32_t ctv_type;
1219 } ctf_varent_t;
1220
1221 Offset Name Description
1222 -----------------------------------------------------------
1223 0x00 'uint32_t ctv_name' Strtab offset of the name
1224
1225 0x04 'uint32_t ctv_type' Type ID of this type
1226
1227 There is no analogue of the function info section yet: v4 will
1228 probably drop this section in favour of a way to put both indexed (thus,
1229 named) and nonindexed symbols into the symtypetab sections at the same
1230 time.
1231
1232
1233 File: ctf-spec.info, Node: The label section, Next: The string section, Prev: The variable section, Up: CTF dictionaries
1234
1235 2.6 The label section
1236 =====================
1237
1238 The label section is a currently-unused facility allowing the tiling of
1239 the type space with names taken from the strtab. The section is an
1240 array of these structures:
1241
1242 typedef struct ctf_lblent
1243 {
1244 uint32_t ctl_label;
1245 uint32_t ctl_type;
1246 } ctf_lblent_t;
1247
1248 Offset Name Description
1249 -------------------------------------------------------------
1250 0x00 'uint32_t ctl_label' Strtab offset of the label
1251
1252 0x04 'uint32_t ctl_type' Type ID of the last type
1253 covered by this label
1254
1255 Semantics will be attached to labels soon, probably in v4 (the plan
1256 is to use them to allow multiple disjoint namespaces in a single CTF
1257 file, removing many uses of CTF archives, in particular in the '.ctf'
1258 section in ELF objects).
1259
1260
1261 File: ctf-spec.info, Node: The string section, Next: Data models, Prev: The label section, Up: CTF dictionaries
1262
1263 2.7 The string section
1264 ======================
1265
1266 This section is a simple ELF-format strtab, starting with a zero byte
1267 (thus ensuring that the string with offset 0 is the null string, as
1268 assumed elsewhere in this spec). The strtab is usually ASCIIbetically
1269 sorted to somewhat improve compression efficiency.
1270
1271 Where the strtab is unusual is the _references_ to it. CTF has two
1272 string tables, the internal strtab and an external strtab associated
1273 with the CTF dictionary at open time: usually, this is the ELF dynamic
1274 strtab ('.dynstr') of a CTF dictionary embedded in an ELF file. We
1275 distinguish between these strtabs by the most significant bit, bit 31,
1276 of the 32-bit strtab references: if it is 0, the offset is in the
1277 internal strtab: if 1, the offset is in the external strtab.
1278
1279 There is a bug workaround in this area: in format v3 (the first
1280 version to have working support for external strtabs), the external
1281 strtab is '.strtab' unless the 'CTF_F_DYNSTR' flag is set on the
1282 dictionary (*note CTF file-wide flags::). Format v4 will introduce a
1283 header field that explicitly names the external strtab, making this flag
1284 unnecessary.
1285
1286
1287 File: ctf-spec.info, Node: Data models, Next: Limits of CTF, Prev: The string section, Up: CTF dictionaries
1288
1289 2.8 Data models
1290 ===============
1291
1292 The data model is a simple integer which indicates the ABI in use on
1293 this platform. Right now, it is very simple, distinguishing only
1294 between 32- and 64-bit types: a model of 1 indicates ILP32, 2 indicats
1295 LP64. The mapping from ABI integer to type sizes is hardwired into
1296 'libctf': currently, we use this to hardwire the size of pointers,
1297 function pointers, and enumerated types,
1298
1299 This is a very kludgy corner of CTF and will probably be replaced
1300 with explicit header fields to record this sort of thing in future.
1301
1302
1303 File: ctf-spec.info, Node: Limits of CTF, Prev: Data models, Up: CTF dictionaries
1304
1305 2.9 Limits of CTF
1306 =================
1307
1308 The following limits are imposed by various aspects of CTF version 3:
1309
1310 'CTF_MAX_TYPE'
1311 Maximum type identifier (maximum number of types accessible with
1312 parent and child containers in use): 0xfffffffe
1313 'CTF_MAX_PTYPE'
1314 Maximum type identifier in a parent dictioanry: maximum number of
1315 types in any one dictionary: 0x7fffffff
1316 'CTF_MAX_NAME'
1317 Maximum offset into a string table: 0x7fffffff
1318 'CTF_MAX_VLEN'
1319 Maximum number of members in a struct, union, or enum: maximum
1320 number of function args: 0xffffff
1321 'CTF_MAX_SIZE'
1322 Maximum size of a 'ctf_stype_t' in bytes before we fall back to
1323 'ctf_type_t': 0xfffffffe bytes
1324
1325 Other maxima without associated macros:
1326 * Maximum value of an enumerated type: 2^32
1327 * Maximum size of an array element: 2^32
1328
1329 These maxima are generally considered to be too low, because C
1330 programs can and do exceed them: they will be lifted in format v4.
1331
1332
1333 File: ctf-spec.info, Node: Index, Prev: CTF dictionaries, Up: Top
1334
1335 Index
1336 *****
1337
1338 [index]
1339 * Menu:
1340
1341 * alignment: CTF Preamble. (line 33)
1342 * archive, CTF archive: CTF archive. (line 6)
1343 * Arrays: Arrays. (line 6)
1344 * bool: Integer types. (line 6)
1345 * Bug workarounds, CTF_F_DYNSTR: The symtypetab sections.
1346 (line 6)
1347 * Bug workarounds, CTF_F_DYNSTR <1>: The string section. (line 19)
1348 * char: Integer types. (line 6)
1349 * Child range: Type indexes and type IDs.
1350 (line 6)
1351 * Complex, double: Floating-point types. (line 6)
1352 * Complex, float: Floating-point types. (line 6)
1353 * Complex, signed double: Floating-point types. (line 6)
1354 * Complex, signed float: Floating-point types. (line 6)
1355 * Complex, unsigned double: Floating-point types. (line 6)
1356 * Complex, unsigned float: Floating-point types. (line 6)
1357 * const: Pointers typedefs and cvr-quals.
1358 (line 6)
1359 * cta_contents: Arrays. (line 20)
1360 * cta_index: Arrays. (line 22)
1361 * cta_nelems: Arrays. (line 29)
1362 * cte_name: Enums. (line 21)
1363 * cte_value: Enums. (line 24)
1364 * CTF header: CTF header. (line 6)
1365 * CTF versions, versions: CTF Preamble. (line 46)
1366 * ctfa_ctfs: CTF archive. (line 76)
1367 * ctfa_magic: CTF archive. (line 63)
1368 * CTFA_MAGIC: CTF archive. (line 64)
1369 * ctfa_model: CTF archive. (line 66)
1370 * ctfa_names: CTF archive. (line 72)
1371 * ctfa_nfiles: CTF archive. (line 71)
1372 * ctf_archive_modent_t: CTF archive. (line 83)
1373 * ctf_archive_modent_t, ctf_offset: CTF archive. (line 88)
1374 * ctf_archive_modent_t, name_offset: CTF archive. (line 86)
1375 * ctf_array_t: Arrays. (line 18)
1376 * ctf_array_t, cta_contents: Arrays. (line 20)
1377 * ctf_array_t, cta_index: Arrays. (line 22)
1378 * ctf_array_t, cta_nelems: Arrays. (line 29)
1379 * CTF_CHAR: Integer types. (line 53)
1380 * ctf_enum_t: Enums. (line 18)
1381 * ctf_enum_t, cte_name: Enums. (line 21)
1382 * ctf_enum_t, cte_value: Enums. (line 24)
1383 * CTF_FP_BITS: Floating-point types. (line 28)
1384 * CTF_FP_CPLX: Floating-point types. (line 47)
1385 * CTF_FP_DCPLX: Floating-point types. (line 48)
1386 * CTF_FP_DIMAGRY: Floating-point types. (line 60)
1387 * CTF_FP_DINTRVL: Floating-point types. (line 54)
1388 * CTF_FP_DOUBLE: Floating-point types. (line 46)
1389 * CTF_FP_ENCODING: Floating-point types. (line 21)
1390 * CTF_FP_IMAGRY: Floating-point types. (line 58)
1391 * CTF_FP_INTRVL: Floating-point types. (line 52)
1392 * CTF_FP_LDCPLX: Floating-point types. (line 49)
1393 * CTF_FP_LDIMAGRY: Floating-point types. (line 62)
1394 * CTF_FP_LDINTRVL: Floating-point types. (line 56)
1395 * CTF_FP_LDOUBLE: Floating-point types. (line 50)
1396 * CTF_FP_OFFSET: Floating-point types. (line 25)
1397 * CTF_FP_SINGLE: Floating-point types. (line 45)
1398 * CTF_F_COMPRESS: CTF file-wide flags. (line 17)
1399 * CTF_F_DYNSTR: CTF file-wide flags. (line 21)
1400 * CTF_F_DYNSTR <1>: The symtypetab sections.
1401 (line 6)
1402 * CTF_F_DYNSTR <2>: The string section. (line 19)
1403 * CTF_F_IDXSORTED: CTF file-wide flags. (line 20)
1404 * CTF_F_IDXSORTED <1>: The symtypetab sections.
1405 (line 6)
1406 * CTF_F_NEWFUNCINFO: CTF file-wide flags. (line 19)
1407 * ctf_header_t: CTF header. (line 44)
1408 * ctf_header_t, cth_cuname: CTF header. (line 61)
1409 * ctf_header_t, cth_flags: CTF Preamble. (line 30)
1410 * ctf_header_t, cth_funcidxoff: CTF header. (line 82)
1411 * ctf_header_t, cth_funcoff: CTF header. (line 74)
1412 * ctf_header_t, cth_lbloff: CTF header. (line 66)
1413 * ctf_header_t, cth_magic: CTF Preamble. (line 24)
1414 * ctf_header_t, cth_objtidxoff: CTF header. (line 78)
1415 * ctf_header_t, cth_objtoff: CTF header. (line 70)
1416 * ctf_header_t, cth_parlabel: CTF header. (line 49)
1417 * ctf_header_t, cth_parname: CTF header. (line 55)
1418 * ctf_header_t, cth_preamble: CTF header. (line 47)
1419 * ctf_header_t, cth_strlen: CTF header. (line 98)
1420 * ctf_header_t, cth_stroff: CTF header. (line 95)
1421 * ctf_header_t, cth_typeoff: CTF header. (line 91)
1422 * ctf_header_t, cth_varoff: CTF header. (line 87)
1423 * ctf_header_t, cth_version: CTF Preamble. (line 28)
1424 * ctf_id_t: Type indexes and type IDs.
1425 (line 6)
1426 * CTF_INT_BITS: Integer types. (line 28)
1427 * CTF_INT_BOOL: Integer types. (line 57)
1428 * CTF_INT_CHAR: Integer types. (line 53)
1429 * CTF_INT_DATA: Integer types. (line 34)
1430 * CTF_INT_DATA <1>: Floating-point types. (line 36)
1431 * CTF_INT_ENCODING: Integer types. (line 20)
1432 * CTF_INT_OFFSET: Integer types. (line 25)
1433 * CTF_INT_SIGNED: Integer types. (line 49)
1434 * CTF_K_CONST: Pointers typedefs and cvr-quals.
1435 (line 6)
1436 * CTF_K_ENUM: Enums. (line 6)
1437 * CTF_K_FLOAT: Floating-point types. (line 6)
1438 * CTF_K_FORWARD: Forward declarations. (line 6)
1439 * CTF_K_INTEGER: Integer types. (line 6)
1440 * CTF_K_POINTER: Pointers typedefs and cvr-quals.
1441 (line 6)
1442 * CTF_K_RESTRICT: Pointers typedefs and cvr-quals.
1443 (line 6)
1444 * CTF_K_SLICE: Slices. (line 6)
1445 * CTF_K_STRUCT: Structs and unions. (line 6)
1446 * CTF_K_TYPEDEF: Pointers typedefs and cvr-quals.
1447 (line 6)
1448 * CTF_K_UNION: Structs and unions. (line 6)
1449 * CTF_K_UNKNOWN: Type kinds. (line 31)
1450 * CTF_K_VOLATILE: Pointers typedefs and cvr-quals.
1451 (line 6)
1452 * ctf_lblent_t: The label section. (line 16)
1453 * ctf_lblent_t, ctl_label: The label section. (line 19)
1454 * ctf_lblent_t, ctl_type: The label section. (line 20)
1455 * ctf_lmember_t: Structs and unions. (line 59)
1456 * ctf_lmember_t, ctlm_name: Structs and unions. (line 61)
1457 * ctf_lmember_t, ctlm_offsethi: Structs and unions. (line 64)
1458 * ctf_lmember_t, ctlm_offsetlo: Structs and unions. (line 68)
1459 * CTF_LSIZE_SENT: The type section. (line 49)
1460 * CTF_LSTRUCT_THRESH: Structs and unions. (line 23)
1461 * CTF_MAGIC: CTF Preamble. (line 25)
1462 * CTF_MAX_LSIZE: Structs and unions. (line 13)
1463 * ctf_member_t: Structs and unions. (line 47)
1464 * ctf_member_t, ctlm_type: Structs and unions. (line 65)
1465 * ctf_member_t, ctm_name: Structs and unions. (line 49)
1466 * ctf_member_t, ctm_offset: Structs and unions. (line 52)
1467 * ctf_member_t, ctm_type: Structs and unions. (line 55)
1468 * ctf_offset: CTF archive. (line 88)
1469 * ctf_preamble_t: CTF Preamble. (line 22)
1470 * ctf_preamble_t, ctp_flags: CTF Preamble. (line 30)
1471 * ctf_preamble_t, ctp_magic: CTF Preamble. (line 24)
1472 * ctf_preamble_t, ctp_version: CTF Preamble. (line 28)
1473 * CTF_SIZE_TO_LSIZE_HI: The type section. (line 79)
1474 * CTF_SIZE_TO_LSIZE_LO: The type section. (line 83)
1475 * ctf_slice_t: Slices. (line 42)
1476 * ctf_slice_t, cts_bits: Slices. (line 59)
1477 * ctf_slice_t, cts_offset: Slices. (line 49)
1478 * ctf_slice_t, cts_type: Slices. (line 44)
1479 * ctf_stype_t: The type section. (line 53)
1480 * ctf_stype_t, ctt_info: The type section. (line 57)
1481 * ctf_stype_t, ctt_size: The type section. (line 62)
1482 * ctf_stype_t, ctt_type: The type section. (line 67)
1483 * CTF_TYPE_INFO: The info word. (line 45)
1484 * CTF_TYPE_LSIZE: The type section. (line 79)
1485 * ctf_type_t: The type section. (line 53)
1486 * ctf_type_t, ctt_info: The type section. (line 57)
1487 * ctf_type_t, ctt_lsizehi: The type section. (line 76)
1488 * ctf_type_t, ctt_lsizelo: The type section. (line 82)
1489 * ctf_type_t, ctt_size: The type section. (line 62)
1490 * CTF_V2_INDEX_TO_TYPE: Type indexes and type IDs.
1491 (line 58)
1492 * CTF_V2_INFO_ISROOT: The info word. (line 45)
1493 * CTF_V2_INFO_KIND: The info word. (line 45)
1494 * CTF_V2_INFO_VLEN: The info word. (line 45)
1495 * CTF_V2_TYPE_ISCHILD: Type indexes and type IDs.
1496 (line 58)
1497 * CTF_V2_TYPE_ISPARENT: Type indexes and type IDs.
1498 (line 58)
1499 * CTF_V2_TYPE_TO_INDEX: Type indexes and type IDs.
1500 (line 58)
1501 * ctf_varent_t: The variable section. (line 21)
1502 * ctf_varent_t, ctv_name: The variable section. (line 24)
1503 * ctf_varent_t, ctv_type: The variable section. (line 26)
1504 * CTF_VERSION_3: CTF Preamble. (line 46)
1505 * cth_cuname: CTF header. (line 61)
1506 * cth_flags: CTF Preamble. (line 30)
1507 * cth_funcidxoff: CTF header. (line 82)
1508 * cth_funcoff: CTF header. (line 74)
1509 * cth_lbloff: CTF header. (line 66)
1510 * cth_magic: CTF Preamble. (line 24)
1511 * cth_objtidxoff: CTF header. (line 78)
1512 * cth_objtoff: CTF header. (line 70)
1513 * cth_parlabel: CTF header. (line 49)
1514 * cth_parname: CTF header. (line 55)
1515 * cth_preamble: CTF header. (line 47)
1516 * cth_strlen: CTF header. (line 98)
1517 * cth_stroff: CTF header. (line 95)
1518 * cth_typeoff: CTF header. (line 91)
1519 * cth_varoff: CTF header. (line 87)
1520 * cth_version: CTF Preamble. (line 28)
1521 * ctlm_name: Structs and unions. (line 61)
1522 * ctlm_offsethi: Structs and unions. (line 64)
1523 * ctlm_offsetlo: Structs and unions. (line 68)
1524 * ctl_label: The label section. (line 19)
1525 * ctl_type: The label section. (line 20)
1526 * ctm_name: Structs and unions. (line 49)
1527 * ctm_offset: Structs and unions. (line 52)
1528 * ctm_type: Structs and unions. (line 55)
1529 * ctm_type <1>: Structs and unions. (line 65)
1530 * ctp_flags: CTF Preamble. (line 30)
1531 * ctp_flags <1>: CTF Preamble. (line 58)
1532 * ctp_magic: CTF Preamble. (line 24)
1533 * ctp_version: CTF Preamble. (line 28)
1534 * cts_bits: Slices. (line 59)
1535 * cts_offset: Slices. (line 49)
1536 * cts_type: Slices. (line 44)
1537 * ctt_info: The type section. (line 57)
1538 * ctt_lsizehi: The type section. (line 76)
1539 * ctt_lsizelo: The type section. (line 82)
1540 * ctt_name: The type section. (line 55)
1541 * ctt_size: The type section. (line 62)
1542 * ctt_type: The type section. (line 67)
1543 * ctv_name: The variable section. (line 24)
1544 * ctv_type: The variable section. (line 26)
1545 * cvr-quals: Pointers typedefs and cvr-quals.
1546 (line 6)
1547 * Data models: Data models. (line 6)
1548 * Data object index section: The symtypetab sections.
1549 (line 6)
1550 * Data object section: The symtypetab sections.
1551 (line 6)
1552 * dictionary, CTF dictionary: CTF dictionaries. (line 6)
1553 * double: Floating-point types. (line 6)
1554 * endianness: CTF Preamble. (line 37)
1555 * enum: Enums. (line 6)
1556 * enum <1>: Forward declarations. (line 6)
1557 * Enums: Enums. (line 6)
1558 * float: Floating-point types. (line 6)
1559 * Floating-point types: Floating-point types. (line 6)
1560 * Forwards: Forward declarations. (line 6)
1561 * Function info index section: The symtypetab sections.
1562 (line 6)
1563 * Function info section: The symtypetab sections.
1564 (line 6)
1565 * Function pointers: Function pointers. (line 6)
1566 * int: Integer types. (line 6)
1567 * Integer types: Integer types. (line 6)
1568 * Label section: The label section. (line 6)
1569 * libctf, effect of slices: Slices. (line 30)
1570 * Limits: Limits of CTF. (line 6)
1571 * long: Integer types. (line 6)
1572 * long long: Integer types. (line 6)
1573 * name_offset: CTF archive. (line 86)
1574 * Overview: Overview. (line 6)
1575 * Parent range: Type indexes and type IDs.
1576 (line 6)
1577 * Pointers: Pointers typedefs and cvr-quals.
1578 (line 6)
1579 * Pointers, to functions: Function pointers. (line 6)
1580 * restrict: Pointers typedefs and cvr-quals.
1581 (line 6)
1582 * Sections, data object: The symtypetab sections.
1583 (line 6)
1584 * Sections, data object index: The symtypetab sections.
1585 (line 6)
1586 * Sections, function info: The symtypetab sections.
1587 (line 6)
1588 * Sections, function info index: The symtypetab sections.
1589 (line 6)
1590 * Sections, header: CTF header. (line 6)
1591 * Sections, label: The label section. (line 6)
1592 * Sections, string: The string section. (line 6)
1593 * Sections, symtypetab: The symtypetab sections.
1594 (line 6)
1595 * Sections, type: The type section. (line 6)
1596 * Sections, variable: The variable section. (line 6)
1597 * short: Integer types. (line 6)
1598 * signed char: Integer types. (line 6)
1599 * signed double: Floating-point types. (line 6)
1600 * signed float: Floating-point types. (line 6)
1601 * signed int: Integer types. (line 6)
1602 * signed long: Integer types. (line 6)
1603 * signed long long: Integer types. (line 6)
1604 * signed short: Integer types. (line 6)
1605 * Slices: Slices. (line 6)
1606 * Slices, effect on ctf_type_kind: Slices. (line 30)
1607 * Slices, effect on ctf_type_reference: Slices. (line 30)
1608 * String section: The string section. (line 6)
1609 * struct: Structs and unions. (line 6)
1610 * struct <1>: Forward declarations. (line 6)
1611 * struct ctf_archive: CTF archive. (line 61)
1612 * struct ctf_archive, ctfa_ctfs: CTF archive. (line 76)
1613 * struct ctf_archive, ctfa_magic: CTF archive. (line 63)
1614 * struct ctf_archive, ctfa_model: CTF archive. (line 66)
1615 * struct ctf_archive, ctfa_names: CTF archive. (line 72)
1616 * struct ctf_archive, ctfa_nfiles: CTF archive. (line 71)
1617 * struct ctf_archive_modent: CTF archive. (line 83)
1618 * struct ctf_archive_modent, ctf_offset: CTF archive. (line 88)
1619 * struct ctf_archive_modent, name_offset: CTF archive. (line 86)
1620 * struct ctf_array: Arrays. (line 18)
1621 * struct ctf_array, cta_contents: Arrays. (line 20)
1622 * struct ctf_array, cta_index: Arrays. (line 22)
1623 * struct ctf_array, cta_nelems: Arrays. (line 29)
1624 * struct ctf_enum: Enums. (line 18)
1625 * struct ctf_enum, cte_name: Enums. (line 21)
1626 * struct ctf_enum, cte_value: Enums. (line 24)
1627 * struct ctf_header: CTF header. (line 44)
1628 * struct ctf_header, cth_cuname: CTF header. (line 61)
1629 * struct ctf_header, cth_flags: CTF Preamble. (line 30)
1630 * struct ctf_header, cth_funcidxoff: CTF header. (line 82)
1631 * struct ctf_header, cth_funcoff: CTF header. (line 74)
1632 * struct ctf_header, cth_lbloff: CTF header. (line 66)
1633 * struct ctf_header, cth_magic: CTF Preamble. (line 24)
1634 * struct ctf_header, cth_objtidxoff: CTF header. (line 78)
1635 * struct ctf_header, cth_objtoff: CTF header. (line 70)
1636 * struct ctf_header, cth_parlabel: CTF header. (line 49)
1637 * struct ctf_header, cth_parname: CTF header. (line 55)
1638 * struct ctf_header, cth_preamble: CTF header. (line 47)
1639 * struct ctf_header, cth_strlen: CTF header. (line 98)
1640 * struct ctf_header, cth_stroff: CTF header. (line 95)
1641 * struct ctf_header, cth_typeoff: CTF header. (line 91)
1642 * struct ctf_header, cth_varoff: CTF header. (line 87)
1643 * struct ctf_header, cth_version: CTF Preamble. (line 28)
1644 * struct ctf_lblent: The label section. (line 16)
1645 * struct ctf_lblent, ctl_label: The label section. (line 19)
1646 * struct ctf_lblent, ctl_type: The label section. (line 20)
1647 * struct ctf_lmember_v2: Structs and unions. (line 59)
1648 * struct ctf_lmember_v2, ctlm_name: Structs and unions. (line 61)
1649 * struct ctf_lmember_v2, ctlm_offsethi: Structs and unions. (line 64)
1650 * struct ctf_lmember_v2, ctlm_offsetlo: Structs and unions. (line 68)
1651 * struct ctf_lmember_v2, ctlm_type: Structs and unions. (line 65)
1652 * struct ctf_member_v2: Structs and unions. (line 47)
1653 * struct ctf_member_v2, ctm_name: Structs and unions. (line 49)
1654 * struct ctf_member_v2, ctm_offset: Structs and unions. (line 52)
1655 * struct ctf_member_v2, ctm_type: Structs and unions. (line 55)
1656 * struct ctf_preamble: CTF Preamble. (line 22)
1657 * struct ctf_preamble, ctp_flags: CTF Preamble. (line 30)
1658 * struct ctf_preamble, ctp_magic: CTF Preamble. (line 24)
1659 * struct ctf_preamble, ctp_version: CTF Preamble. (line 28)
1660 * struct ctf_slice: Slices. (line 42)
1661 * struct ctf_slice, cts_bits: Slices. (line 59)
1662 * struct ctf_slice, cts_offset: Slices. (line 49)
1663 * struct ctf_slice, cts_type: Slices. (line 44)
1664 * struct ctf_stype: The type section. (line 53)
1665 * struct ctf_stype, ctt_info: The type section. (line 57)
1666 * struct ctf_stype, ctt_size: The type section. (line 62)
1667 * struct ctf_stype, ctt_type: The type section. (line 67)
1668 * struct ctf_type: The type section. (line 53)
1669 * struct ctf_type, ctt_info: The type section. (line 57)
1670 * struct ctf_type, ctt_lsizehi: The type section. (line 76)
1671 * struct ctf_type, ctt_lsizelo: The type section. (line 82)
1672 * struct ctf_type, ctt_size: The type section. (line 62)
1673 * struct ctf_varent: The variable section. (line 21)
1674 * struct ctf_varent, ctv_name: The variable section. (line 24)
1675 * struct ctf_varent, ctv_type: The variable section. (line 26)
1676 * Structures: Structs and unions. (line 6)
1677 * Symtypetab section: The symtypetab sections.
1678 (line 6)
1679 * Type IDs: Type indexes and type IDs.
1680 (line 6)
1681 * Type IDs, ranges: Type indexes and type IDs.
1682 (line 6)
1683 * Type indexes: Type indexes and type IDs.
1684 (line 6)
1685 * Type kinds: Type kinds. (line 6)
1686 * Type section: The type section. (line 6)
1687 * Type, IDs of: Type indexes and type IDs.
1688 (line 6)
1689 * Type, indexes of: Type indexes and type IDs.
1690 (line 6)
1691 * Type, kinds of: Type kinds. (line 6)
1692 * typedef: Pointers typedefs and cvr-quals.
1693 (line 6)
1694 * Typedefs: Pointers typedefs and cvr-quals.
1695 (line 6)
1696 * Types, floating-point: Floating-point types. (line 6)
1697 * Types, integer: Integer types. (line 6)
1698 * Types, slices of integral: Slices. (line 6)
1699 * union: Structs and unions. (line 6)
1700 * union <1>: Forward declarations. (line 6)
1701 * Unions: Structs and unions. (line 6)
1702 * unsigned char: Integer types. (line 6)
1703 * unsigned double: Floating-point types. (line 6)
1704 * unsigned float: Floating-point types. (line 6)
1705 * unsigned int: Integer types. (line 6)
1706 * unsigned long: Integer types. (line 6)
1707 * unsigned long long: Integer types. (line 6)
1708 * unsigned short: Integer types. (line 6)
1709 * Unused bits: Floating-point types. (line 52)
1710 * Unused bits <1>: Floating-point types. (line 54)
1711 * Unused bits <2>: Floating-point types. (line 56)
1712 * Unused bits <3>: Floating-point types. (line 58)
1713 * Unused bits <4>: Floating-point types. (line 60)
1714 * Unused bits <5>: Floating-point types. (line 62)
1715 * Variable section: The variable section. (line 6)
1716 * volatile: Pointers typedefs and cvr-quals.
1717 (line 6)
1718
1719
1720
1721 Tag Table:
1722 Node: Top548
1723 Node: Overview878
1724 Node: CTF archive4165
1725 Node: CTF dictionaries8791
1726 Node: CTF Preamble9208
1727 Node: CTF file-wide flags11818
1728 Node: CTF header13276
1729 Node: The type section19200
1730 Node: The info word23865
1731 Node: Type indexes and type IDs26395
1732 Node: Type kinds29763
1733 Node: Integer types33056
1734 Node: Floating-point types36604
1735 Node: Slices40629
1736 Node: Pointers typedefs and cvr-quals44133
1737 Node: Arrays45304
1738 Node: Function pointers47035
1739 Node: Enums47700
1740 Node: Structs and unions48982
1741 Node: Forward declarations52839
1742 Node: The symtypetab sections54418
1743 Node: The variable section57496
1744 Node: The label section58634
1745 Node: The string section59609
1746 Node: Data models60871
1747 Node: Limits of CTF61540
1748 Node: Index62585
1749
1750 End Tag Table
1751
1752
1753 Local Variables:
1754 coding: utf-8
1755 End:
1756