4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
23 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
26 * Copyright 2018 Joyent, Inc.
32 #include <sys/types.h>
39 * CTF - Compact ANSI-C Type Format
41 * This file format can be used to compactly represent the information needed
42 * by a debugger to interpret the ANSI-C types used by a given program.
43 * Traditionally, this kind of information is generated by the compiler when
44 * invoked with the -g flag and is stored in "stabs" strings or in the more
45 * modern DWARF format. CTF provides a representation of only the information
46 * that is relevant to debugging a complex, optimized C program such as the
47 * operating system kernel in a form that is significantly more compact than
48 * the equivalent stabs or DWARF representation. The format is data-model
49 * independent, so consumers do not need different code depending on whether
50 * they are 32-bit or 64-bit programs. CTF assumes that a standard ELF symbol
51 * table is available for use in the debugger, and uses the structure and data
52 * of the symbol table to avoid storing redundant information. The CTF data
53 * may be compressed on disk or in memory, indicated by a bit in the header.
54 * CTF may be interpreted in a raw disk file, or it may be stored in an ELF
55 * section, typically named .SUNW_ctf. Data structures are aligned so that
56 * a raw CTF file or CTF ELF section may be manipulated using mmap(2).
58 * The CTF file or section itself has the following structure:
60 * +--------+--------+---------+----------+-------+--------+
61 * | file | type | data | function | data | string |
62 * | header | labels | objects | info | types | table |
63 * +--------+--------+---------+----------+-------+--------+
65 * The file header stores a magic number and version information, encoding
66 * flags, and the byte offset of each of the sections relative to the end of the
67 * header itself. If the CTF data has been uniquified against another set of
68 * CTF data, a reference to that data also appears in the the header. This
69 * reference is the name of the label corresponding to the types uniquified
72 * Following the header is a list of labels, used to group the types included in
73 * the data types section. Each label is accompanied by a type ID i. A given
74 * label refers to the group of types whose IDs are in the range [0, i].
76 * Data object and function records are stored in the same order as they appear
77 * in the corresponding symbol table, except that symbols marked SHN_UNDEF are
78 * not stored and symbols that have no type data are padded out with zeroes.
79 * For each data object, the type ID (a small integer) is recorded. For each
80 * function, the type ID of the return type and argument types is recorded.
82 * The data types section is a list of variable size records that represent each
83 * type, in order by their ID. The types themselves form a directed graph,
84 * where each node may contain one or more outgoing edges to other type nodes,
85 * denoted by their ID.
87 * Strings are recorded as a string table ID (0 or 1) and a byte offset into the
88 * string table. String table 0 is the internal CTF string table. String table
89 * 1 is the external string table, which is the string table associated with the
90 * ELF symbol table for this object. CTF does not record any strings that are
91 * already in the symbol table, and the CTF string table does not contain any
94 * If the CTF data has been merged with another parent CTF object, some outgoing
95 * edges may refer to type nodes that exist in another CTF object. The debugger
96 * and libctf library are responsible for connecting the appropriate objects
97 * together so that the full set of types can be explored and manipulated.
100 #define CTF_MAX_TYPE 0xffff /* max type identifier value */
101 #define CTF_MAX_NAME 0x7fffffff /* max offset into a string table */
102 #define CTF_MAX_VLEN 0x3ff /* max struct, union, enum members or args */
103 #define CTF_MAX_INTOFF 0xff /* max offset of intrinsic value in bits */
104 #define CTF_MAX_INTBITS 0xffff /* max size of an intrinsic in bits */
107 #define CTF_MAX_SIZE 0xfffe /* max size of a type in bytes */
108 #define CTF_LSIZE_SENT 0xffff /* sentinel for ctt_size */
109 #define CTF_MAX_LSIZE UINT64_MAX
111 typedef struct ctf_preamble
{
112 ushort_t ctp_magic
; /* magic number (CTF_MAGIC) */
113 uchar_t ctp_version
; /* data format version number (CTF_VERSION) */
114 uchar_t ctp_flags
; /* flags (see below) */
117 typedef struct ctf_header
{
118 ctf_preamble_t cth_preamble
;
119 uint_t cth_parlabel
; /* ref to name of parent lbl uniq'd against */
120 uint_t cth_parname
; /* ref to basename of parent */
121 uint_t cth_lbloff
; /* offset of label section */
122 uint_t cth_objtoff
; /* offset of object section */
123 uint_t cth_funcoff
; /* offset of function section */
124 uint_t cth_typeoff
; /* offset of type section */
125 uint_t cth_stroff
; /* offset of string section */
126 uint_t cth_strlen
; /* length of string section in bytes */
129 #define cth_magic cth_preamble.ctp_magic
130 #define cth_version cth_preamble.ctp_version
131 #define cth_flags cth_preamble.ctp_flags
133 #ifdef CTF_OLD_VERSIONS
135 typedef struct ctf_header_v1
{
136 ctf_preamble_t cth_preamble
;
144 #endif /* CTF_OLD_VERSIONS */
146 #define CTF_MAGIC 0xcff1 /* magic number identifying header */
148 /* data format version number */
149 #define CTF_VERSION_1 1
150 #define CTF_VERSION_2 2
151 #define CTF_VERSION CTF_VERSION_2 /* current version */
153 #define CTF_F_COMPRESS 0x1 /* data buffer is compressed */
155 typedef struct ctf_lblent
{
156 uint_t ctl_label
; /* ref to name of label */
157 uint_t ctl_typeidx
; /* last type associated with this label */
160 typedef struct ctf_stype
{
161 uint_t ctt_name
; /* reference to name in string table */
162 ushort_t ctt_info
; /* encoded kind, variant length (see below) */
164 ushort_t _size
; /* size of entire type in bytes */
165 ushort_t _type
; /* reference to another type */
170 * type sizes, measured in bytes, come in two flavors. 99% of them fit within
171 * (USHRT_MAX - 1), and thus can be stored in the ctt_size member of a
172 * ctf_stype_t. The maximum value for these sizes is CTF_MAX_SIZE. The sizes
173 * larger than CTF_MAX_SIZE must be stored in the ctt_lsize member of a
174 * ctf_type_t. Use of this member is indicated by the presence of
175 * CTF_LSIZE_SENT in ctt_size.
177 typedef struct ctf_type
{
178 uint_t ctt_name
; /* reference to name in string table */
179 ushort_t ctt_info
; /* encoded kind, variant length (see below) */
181 ushort_t _size
; /* always CTF_LSIZE_SENT */
182 ushort_t _type
; /* do not use */
184 uint_t ctt_lsizehi
; /* high 32 bits of type size in bytes */
185 uint_t ctt_lsizelo
; /* low 32 bits of type size in bytes */
188 #define ctt_size _u._size /* for fundamental types that have a size */
189 #define ctt_type _u._type /* for types that reference another type */
192 * The following macros compose and decompose values for ctt_info and
193 * ctt_name, as well as other structures that contain name references.
195 * ------------------------
196 * ctt_info: | kind | isroot | vlen |
197 * ------------------------
200 * kind = CTF_INFO_KIND(c.ctt_info); <-- CTF_K_* value (see below)
201 * vlen = CTF_INFO_VLEN(c.ctt_info); <-- length of variable data list
203 * stid = CTF_NAME_STID(c.ctt_name); <-- string table id number (0 or 1)
204 * offset = CTF_NAME_OFFSET(c.ctt_name); <-- string table byte offset
206 * c.ctt_info = CTF_TYPE_INFO(kind, vlen);
207 * c.ctt_name = CTF_TYPE_NAME(stid, offset);
210 #define CTF_INFO_KIND(info) (((info) & 0xf800) >> 11)
211 #define CTF_INFO_ISROOT(info) (((info) & 0x0400) >> 10)
212 #define CTF_INFO_VLEN(info) (((info) & CTF_MAX_VLEN))
214 #define CTF_NAME_STID(name) ((name) >> 31)
215 #define CTF_NAME_OFFSET(name) ((name) & 0x7fffffff)
217 #define CTF_TYPE_INFO(kind, isroot, vlen) \
218 (((kind) << 11) | (((isroot) ? 1 : 0) << 10) | ((vlen) & CTF_MAX_VLEN))
220 #define CTF_TYPE_NAME(stid, offset) \
221 (((stid) << 31) | ((offset) & 0x7fffffff))
223 #define CTF_CHILD_START (0x8000)
224 #define CTF_TYPE_ISPARENT(id) ((id) < CTF_CHILD_START)
225 #define CTF_TYPE_ISCHILD(id) ((id) >= CTF_CHILD_START)
227 #define CTF_TYPE_TO_INDEX(id) ((id) & (CTF_CHILD_START - 1))
228 #define CTF_INDEX_TO_TYPE(id, child) \
229 ((child) ? ((id) | CTF_CHILD_START) : (id))
230 #define CTF_PARENT_SHIFT 15
232 #define CTF_STRTAB_0 0 /* symbolic define for string table id 0 */
233 #define CTF_STRTAB_1 1 /* symbolic define for string table id 1 */
235 #define CTF_TYPE_LSIZE(cttp) \
236 (((uint64_t)(cttp)->ctt_lsizehi) << 32 | (cttp)->ctt_lsizelo)
237 #define CTF_SIZE_TO_LSIZE_HI(size) ((uint32_t)((uint64_t)(size) >> 32))
238 #define CTF_SIZE_TO_LSIZE_LO(size) ((uint32_t)(size))
240 #ifdef CTF_OLD_VERSIONS
242 #define CTF_INFO_KIND_V1(info) (((info) & 0xf000) >> 12)
243 #define CTF_INFO_ISROOT_V1(info) (((info) & 0x0800) >> 11)
244 #define CTF_INFO_VLEN_V1(info) (((info) & 0x07ff))
246 #define CTF_TYPE_INFO_V1(kind, isroot, vlen) \
247 (((kind) << 12) | (((isroot) ? 1 : 0) << 11) | ((vlen) & 0x07ff))
249 #endif /* CTF_OLD_VERSIONS */
252 * Values for CTF_TYPE_KIND(). If the kind has an associated data list,
253 * CTF_INFO_VLEN() will extract the number of elements in the list, and
254 * the type of each element is shown in the comments below.
256 #define CTF_K_UNKNOWN 0 /* unknown type (used for padding) */
257 #define CTF_K_INTEGER 1 /* variant data is CTF_INT_DATA() (see below) */
258 #define CTF_K_FLOAT 2 /* variant data is CTF_FP_DATA() (see below) */
259 #define CTF_K_POINTER 3 /* ctt_type is referenced type */
260 #define CTF_K_ARRAY 4 /* variant data is single ctf_array_t */
261 #define CTF_K_FUNCTION 5 /* ctt_type is return type, variant data is */
262 /* list of argument types (ushort_t's) */
263 #define CTF_K_STRUCT 6 /* variant data is list of ctf_member_t's */
264 #define CTF_K_UNION 7 /* variant data is list of ctf_member_t's */
265 #define CTF_K_ENUM 8 /* variant data is list of ctf_enum_t's */
266 #define CTF_K_FORWARD 9 /* no additional data; ctt_name is tag */
267 #define CTF_K_TYPEDEF 10 /* ctt_type is referenced type */
268 #define CTF_K_VOLATILE 11 /* ctt_type is base type */
269 #define CTF_K_CONST 12 /* ctt_type is base type */
270 #define CTF_K_RESTRICT 13 /* ctt_type is base type */
272 #define CTF_K_MAX 31 /* Maximum possible CTF_K_* value */
275 * Values for ctt_type when kind is CTF_K_INTEGER. The flags, offset in bits,
276 * and size in bits are encoded as a single word using the following macros.
278 #define CTF_INT_ENCODING(data) (((data) & 0xff000000) >> 24)
279 #define CTF_INT_OFFSET(data) (((data) & 0x00ff0000) >> 16)
280 #define CTF_INT_BITS(data) (((data) & 0x0000ffff))
282 #define CTF_INT_DATA(encoding, offset, bits) \
283 (((encoding) << 24) | ((offset) << 16) | (bits))
285 #define CTF_INT_SIGNED 0x01 /* integer is signed (otherwise unsigned) */
286 #define CTF_INT_CHAR 0x02 /* character display format */
287 #define CTF_INT_BOOL 0x04 /* boolean display format */
288 #define CTF_INT_VARARGS 0x08 /* varargs display format */
291 * Values for ctt_type when kind is CTF_K_FLOAT. The encoding, offset in bits,
292 * and size in bits are encoded as a single word using the following macros.
294 #define CTF_FP_ENCODING(data) (((data) & 0xff000000) >> 24)
295 #define CTF_FP_OFFSET(data) (((data) & 0x00ff0000) >> 16)
296 #define CTF_FP_BITS(data) (((data) & 0x0000ffff))
298 #define CTF_FP_DATA(encoding, offset, bits) \
299 (((encoding) << 24) | ((offset) << 16) | (bits))
301 #define CTF_FP_SINGLE 1 /* IEEE 32-bit float encoding */
302 #define CTF_FP_DOUBLE 2 /* IEEE 64-bit float encoding */
303 #define CTF_FP_CPLX 3 /* Complex encoding */
304 #define CTF_FP_DCPLX 4 /* Double complex encoding */
305 #define CTF_FP_LDCPLX 5 /* Long double complex encoding */
306 #define CTF_FP_LDOUBLE 6 /* Long double encoding */
307 #define CTF_FP_INTRVL 7 /* Interval (2x32-bit) encoding */
308 #define CTF_FP_DINTRVL 8 /* Double interval (2x64-bit) encoding */
309 #define CTF_FP_LDINTRVL 9 /* Long double interval (2x128-bit) encoding */
310 #define CTF_FP_IMAGRY 10 /* Imaginary (32-bit) encoding */
311 #define CTF_FP_DIMAGRY 11 /* Long imaginary (64-bit) encoding */
312 #define CTF_FP_LDIMAGRY 12 /* Long double imaginary (128-bit) encoding */
314 #define CTF_FP_MAX 12 /* Maximum possible CTF_FP_* value */
316 typedef struct ctf_array
{
317 ushort_t cta_contents
; /* reference to type of array contents */
318 ushort_t cta_index
; /* reference to type of array index */
319 uint_t cta_nelems
; /* number of elements */
323 * Most structure members have bit offsets that can be expressed using a
324 * short. Some don't. ctf_member_t is used for structs which cannot
325 * contain any of these large offsets, whereas ctf_lmember_t is used in the
326 * latter case. If ctt_size for a given struct is >= 8192 bytes, all members
327 * will be stored as type ctf_lmember_t.
330 #define CTF_LSTRUCT_THRESH 8192
332 typedef struct ctf_member
{
333 uint_t ctm_name
; /* reference to name in string table */
334 ushort_t ctm_type
; /* reference to type of member */
335 ushort_t ctm_offset
; /* offset of this member in bits */
338 typedef struct ctf_lmember
{
339 uint_t ctlm_name
; /* reference to name in string table */
340 ushort_t ctlm_type
; /* reference to type of member */
341 ushort_t ctlm_pad
; /* padding */
342 uint_t ctlm_offsethi
; /* high 32 bits of member offset in bits */
343 uint_t ctlm_offsetlo
; /* low 32 bits of member offset in bits */
346 #define CTF_LMEM_OFFSET(ctlmp) \
347 (((uint64_t)(ctlmp)->ctlm_offsethi) << 32 | (ctlmp)->ctlm_offsetlo)
348 #define CTF_OFFSET_TO_LMEMHI(offset) ((uint32_t)((uint64_t)(offset) >> 32))
349 #define CTF_OFFSET_TO_LMEMLO(offset) ((uint32_t)(offset))
351 typedef struct ctf_enum
{
352 uint_t cte_name
; /* reference to name in string table */
353 int cte_value
; /* value associated with this name */