1/*
2 * CDDL HEADER START
3 *
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
7 * with the License.
8 *
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.
13 *
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]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#ifndef	_CTF_H
28#define	_CTF_H
29
30#pragma ident	"@(#)ctf.h	1.5	05/06/08 SMI"
31
32#include <sys/types.h>
33
34#ifdef	__cplusplus
35extern "C" {
36#endif
37
38/*
39 * CTF - Compact ANSI-C Type Format
40 *
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).
57 *
58 * The CTF file or section itself has the following structure:
59 *
60 * +--------+--------+---------+----------+-------+--------+
61 * |  file  |  type  |  data   | function | data  | string |
62 * | header | labels | objects |   info   | types | table  |
63 * +--------+--------+---------+----------+-------+--------+
64 *
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
70 * against.
71 *
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].
75 *
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.
81 *
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.
86 *
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
92 * duplicated strings.
93 *
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.
98 */
99
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 */
105
106/* See ctf_type_t */
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
110
111typedef 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) */
115} ctf_preamble_t;
116
117typedef 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 */
127} ctf_header_t;
128
129#define	cth_magic   cth_preamble.ctp_magic
130#define	cth_version cth_preamble.ctp_version
131#define	cth_flags   cth_preamble.ctp_flags
132
133#ifdef CTF_OLD_VERSIONS
134
135typedef struct ctf_header_v1 {
136	ctf_preamble_t cth_preamble;
137	uint_t cth_objtoff;
138	uint_t cth_funcoff;
139	uint_t cth_typeoff;
140	uint_t cth_stroff;
141	uint_t cth_strlen;
142} ctf_header_v1_t;
143
144#endif /* CTF_OLD_VERSIONS */
145
146#define	CTF_MAGIC	0xcff1	/* magic number identifying header */
147
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 */
152
153#define	CTF_F_COMPRESS	0x1	/* data buffer is compressed */
154
155typedef struct ctf_lblent {
156	uint_t ctl_label;	/* ref to name of label */
157	uint_t ctl_typeidx;	/* last type associated with this label */
158} ctf_lblent_t;
159
160typedef 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) */
163	union {
164		ushort_t _size;	/* size of entire type in bytes */
165		ushort_t _type;	/* reference to another type */
166	} _u;
167} ctf_stype_t;
168
169/*
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.
176 */
177typedef 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) */
180	union {
181		ushort_t _size;	/* always CTF_LSIZE_SENT */
182		ushort_t _type; /* do not use */
183	} _u;
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 */
186} ctf_type_t;
187
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 */
190
191/*
192 * The following macros compose and decompose values for ctt_info and
193 * ctt_name, as well as other structures that contain name references.
194 *
195 *             ------------------------
196 * ctt_info:   | kind | isroot | vlen |
197 *             ------------------------
198 *             15   11    10    9     0
199 *
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
202 *
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
205 *
206 * c.ctt_info = CTF_TYPE_INFO(kind, vlen);
207 * c.ctt_name = CTF_TYPE_NAME(stid, offset);
208 */
209
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))
213
214#define	CTF_NAME_STID(name)	((name) >> 31)
215#define	CTF_NAME_OFFSET(name)	((name) & 0x7fffffff)
216
217#define	CTF_TYPE_INFO(kind, isroot, vlen) \
218	(((kind) << 11) | (((isroot) ? 1 : 0) << 10) | ((vlen) & CTF_MAX_VLEN))
219
220#define	CTF_TYPE_NAME(stid, offset) \
221	(((stid) << 31) | ((offset) & 0x7fffffff))
222
223#define	CTF_TYPE_ISPARENT(id)	((id) < 0x8000)
224#define	CTF_TYPE_ISCHILD(id)	((id) > 0x7fff)
225
226#define	CTF_TYPE_TO_INDEX(id)		((id) & 0x7fff)
227#define	CTF_INDEX_TO_TYPE(id, child)	((child) ? ((id) | 0x8000) : (id))
228#define	CTF_PARENT_SHIFT	15
229
230#define	CTF_STRTAB_0	0	/* symbolic define for string table id 0 */
231#define	CTF_STRTAB_1	1	/* symbolic define for string table id 1 */
232
233#define	CTF_TYPE_LSIZE(cttp) \
234	(((uint64_t)(cttp)->ctt_lsizehi) << 32 | (cttp)->ctt_lsizelo)
235#define	CTF_SIZE_TO_LSIZE_HI(size)	((uint32_t)((uint64_t)(size) >> 32))
236#define	CTF_SIZE_TO_LSIZE_LO(size)	((uint32_t)(size))
237
238#ifdef CTF_OLD_VERSIONS
239
240#define	CTF_INFO_KIND_V1(info)		(((info) & 0xf000) >> 12)
241#define	CTF_INFO_ISROOT_V1(info)	(((info) & 0x0800) >> 11)
242#define	CTF_INFO_VLEN_V1(info)		(((info) & 0x07ff))
243
244#define	CTF_TYPE_INFO_V1(kind, isroot, vlen) \
245	(((kind) << 12) | (((isroot) ? 1 : 0) << 11) | ((vlen) & 0x07ff))
246
247#endif /* CTF_OLD_VERSIONS */
248
249/*
250 * Values for CTF_TYPE_KIND().  If the kind has an associated data list,
251 * CTF_INFO_VLEN() will extract the number of elements in the list, and
252 * the type of each element is shown in the comments below.
253 */
254#define	CTF_K_UNKNOWN	0	/* unknown type (used for padding) */
255#define	CTF_K_INTEGER	1	/* variant data is CTF_INT_DATA() (see below) */
256#define	CTF_K_FLOAT	2	/* variant data is CTF_FP_DATA() (see below) */
257#define	CTF_K_POINTER	3	/* ctt_type is referenced type */
258#define	CTF_K_ARRAY	4	/* variant data is single ctf_array_t */
259#define	CTF_K_FUNCTION	5	/* ctt_type is return type, variant data is */
260				/* list of argument types (ushort_t's) */
261#define	CTF_K_STRUCT	6	/* variant data is list of ctf_member_t's */
262#define	CTF_K_UNION	7	/* variant data is list of ctf_member_t's */
263#define	CTF_K_ENUM	8	/* variant data is list of ctf_enum_t's */
264#define	CTF_K_FORWARD	9	/* no additional data; ctt_name is tag */
265#define	CTF_K_TYPEDEF	10	/* ctt_type is referenced type */
266#define	CTF_K_VOLATILE	11	/* ctt_type is base type */
267#define	CTF_K_CONST	12	/* ctt_type is base type */
268#define	CTF_K_RESTRICT	13	/* ctt_type is base type */
269
270#define	CTF_K_MAX	31	/* Maximum possible CTF_K_* value */
271
272/*
273 * Values for ctt_type when kind is CTF_K_INTEGER.  The flags, offset in bits,
274 * and size in bits are encoded as a single word using the following macros.
275 */
276#define	CTF_INT_ENCODING(data)	(((data) & 0xff000000) >> 24)
277#define	CTF_INT_OFFSET(data)	(((data) & 0x00ff0000) >> 16)
278#define	CTF_INT_BITS(data)	(((data) & 0x0000ffff))
279
280#define	CTF_INT_DATA(encoding, offset, bits) \
281	(((encoding) << 24) | ((offset) << 16) | (bits))
282
283#define	CTF_INT_SIGNED	0x01	/* integer is signed (otherwise unsigned) */
284#define	CTF_INT_CHAR	0x02	/* character display format */
285#define	CTF_INT_BOOL	0x04	/* boolean display format */
286#define	CTF_INT_VARARGS	0x08	/* varargs display format */
287
288/*
289 * Values for ctt_type when kind is CTF_K_FLOAT.  The encoding, offset in bits,
290 * and size in bits are encoded as a single word using the following macros.
291 */
292#define	CTF_FP_ENCODING(data)	(((data) & 0xff000000) >> 24)
293#define	CTF_FP_OFFSET(data)	(((data) & 0x00ff0000) >> 16)
294#define	CTF_FP_BITS(data)	(((data) & 0x0000ffff))
295
296#define	CTF_FP_DATA(encoding, offset, bits) \
297	(((encoding) << 24) | ((offset) << 16) | (bits))
298
299#define	CTF_FP_SINGLE	1	/* IEEE 32-bit float encoding */
300#define	CTF_FP_DOUBLE	2	/* IEEE 64-bit float encoding */
301#define	CTF_FP_CPLX	3	/* Complex encoding */
302#define	CTF_FP_DCPLX	4	/* Double complex encoding */
303#define	CTF_FP_LDCPLX	5	/* Long double complex encoding */
304#define	CTF_FP_LDOUBLE	6	/* Long double encoding */
305#define	CTF_FP_INTRVL	7	/* Interval (2x32-bit) encoding */
306#define	CTF_FP_DINTRVL	8	/* Double interval (2x64-bit) encoding */
307#define	CTF_FP_LDINTRVL	9	/* Long double interval (2x128-bit) encoding */
308#define	CTF_FP_IMAGRY	10	/* Imaginary (32-bit) encoding */
309#define	CTF_FP_DIMAGRY	11	/* Long imaginary (64-bit) encoding */
310#define	CTF_FP_LDIMAGRY	12	/* Long double imaginary (128-bit) encoding */
311
312#define	CTF_FP_MAX	12	/* Maximum possible CTF_FP_* value */
313
314typedef struct ctf_array {
315	ushort_t cta_contents;	/* reference to type of array contents */
316	ushort_t cta_index;	/* reference to type of array index */
317	uint_t cta_nelems;	/* number of elements */
318} ctf_array_t;
319
320/*
321 * Most structure members have bit offsets that can be expressed using a
322 * short.  Some don't.  ctf_member_t is used for structs which cannot
323 * contain any of these large offsets, whereas ctf_lmember_t is used in the
324 * latter case.  If ctt_size for a given struct is >= 8192 bytes, all members
325 * will be stored as type ctf_lmember_t.
326 */
327
328#define	CTF_LSTRUCT_THRESH	8192
329
330typedef struct ctf_member {
331	uint_t ctm_name;	/* reference to name in string table */
332	ushort_t ctm_type;	/* reference to type of member */
333	ushort_t ctm_offset;	/* offset of this member in bits */
334} ctf_member_t;
335
336typedef struct ctf_lmember {
337	uint_t ctlm_name;	/* reference to name in string table */
338	ushort_t ctlm_type;	/* reference to type of member */
339	ushort_t ctlm_pad;	/* padding */
340	uint_t ctlm_offsethi;	/* high 32 bits of member offset in bits */
341	uint_t ctlm_offsetlo;	/* low 32 bits of member offset in bits */
342} ctf_lmember_t;
343
344#define	CTF_LMEM_OFFSET(ctlmp) \
345	(((uint64_t)(ctlmp)->ctlm_offsethi) << 32 | (ctlmp)->ctlm_offsetlo)
346#define	CTF_OFFSET_TO_LMEMHI(offset)	((uint32_t)((uint64_t)(offset) >> 32))
347#define	CTF_OFFSET_TO_LMEMLO(offset)	((uint32_t)(offset))
348
349typedef struct ctf_enum {
350	uint_t cte_name;	/* reference to name in string table */
351	int cte_value;		/* value associated with this name */
352} ctf_enum_t;
353
354#ifdef	__cplusplus
355}
356#endif
357
358#endif	/* _CTF_H */
359