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 2005 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #pragma ident "%Z%%M% %I% %E% SMI"
28
29 /*
30 * CTF Declaration Stack
31 *
32 * In order to implement ctf_type_name(), we must convert a type graph back
33 * into a C type declaration. Unfortunately, a type graph represents a storage
34 * class ordering of the type whereas a type declaration must obey the C rules
35 * for operator precedence, and the two orderings are frequently in conflict.
36 * For example, consider these CTF type graphs and their C declarations:
37 *
38 * CTF_K_POINTER -> CTF_K_FUNCTION -> CTF_K_INTEGER : int (*)()
39 * CTF_K_POINTER -> CTF_K_ARRAY -> CTF_K_INTEGER : int (*)[]
40 *
41 * In each case, parentheses are used to raise operator * to higher lexical
42 * precedence, so the string form of the C declaration cannot be constructed by
43 * walking the type graph links and forming the string from left to right.
44 *
45 * The functions in this file build a set of stacks from the type graph nodes
46 * corresponding to the C operator precedence levels in the appropriate order.
47 * The code in ctf_type_name() can then iterate over the levels and nodes in
48 * lexical precedence order and construct the final C declaration string.
49 */
50
51 #include <ctf_impl.h>
52
53 void
ctf_decl_init(ctf_decl_t * cd,char * buf,size_t len)54 ctf_decl_init(ctf_decl_t *cd, char *buf, size_t len)
55 {
56 int i;
57
58 bzero(cd, sizeof (ctf_decl_t));
59
60 for (i = CTF_PREC_BASE; i < CTF_PREC_MAX; i++)
61 cd->cd_order[i] = CTF_PREC_BASE - 1;
62
63 cd->cd_qualp = CTF_PREC_BASE;
64 cd->cd_ordp = CTF_PREC_BASE;
65
66 cd->cd_buf = buf;
67 cd->cd_ptr = buf;
68 cd->cd_end = buf + len;
69 }
70
71 void
ctf_decl_fini(ctf_decl_t * cd)72 ctf_decl_fini(ctf_decl_t *cd)
73 {
74 ctf_decl_node_t *cdp, *ndp;
75 int i;
76
77 for (i = CTF_PREC_BASE; i < CTF_PREC_MAX; i++) {
78 for (cdp = ctf_list_next(&cd->cd_nodes[i]);
79 cdp != NULL; cdp = ndp) {
80 ndp = ctf_list_next(cdp);
81 ctf_free(cdp, sizeof (ctf_decl_node_t));
82 }
83 }
84 }
85
86 void
ctf_decl_push(ctf_decl_t * cd,ctf_file_t * fp,ctf_id_t type)87 ctf_decl_push(ctf_decl_t *cd, ctf_file_t *fp, ctf_id_t type)
88 {
89 ctf_decl_node_t *cdp;
90 ctf_decl_prec_t prec;
91 uint_t kind, n = 1;
92 int is_qual = 0;
93
94 const ctf_type_t *tp;
95 ctf_arinfo_t ar;
96
97 if ((tp = ctf_lookup_by_id(&fp, type)) == NULL) {
98 cd->cd_err = fp->ctf_errno;
99 return;
100 }
101
102 switch (kind = LCTF_INFO_KIND(fp, tp->ctt_info)) {
103 case CTF_K_ARRAY:
104 (void) ctf_array_info(fp, type, &ar);
105 ctf_decl_push(cd, fp, ar.ctr_contents);
106 n = ar.ctr_nelems;
107 prec = CTF_PREC_ARRAY;
108 break;
109
110 case CTF_K_TYPEDEF:
111 if (ctf_strptr(fp, tp->ctt_name)[0] == '\0') {
112 ctf_decl_push(cd, fp, tp->ctt_type);
113 return;
114 }
115 prec = CTF_PREC_BASE;
116 break;
117
118 case CTF_K_FUNCTION:
119 ctf_decl_push(cd, fp, tp->ctt_type);
120 prec = CTF_PREC_FUNCTION;
121 break;
122
123 case CTF_K_POINTER:
124 ctf_decl_push(cd, fp, tp->ctt_type);
125 prec = CTF_PREC_POINTER;
126 break;
127
128 case CTF_K_VOLATILE:
129 case CTF_K_CONST:
130 case CTF_K_RESTRICT:
131 ctf_decl_push(cd, fp, tp->ctt_type);
132 prec = cd->cd_qualp;
133 is_qual++;
134 break;
135
136 default:
137 prec = CTF_PREC_BASE;
138 }
139
140 if ((cdp = ctf_alloc(sizeof (ctf_decl_node_t))) == NULL) {
141 cd->cd_err = EAGAIN;
142 return;
143 }
144
145 cdp->cd_type = type;
146 cdp->cd_kind = kind;
147 cdp->cd_n = n;
148
149 if (ctf_list_next(&cd->cd_nodes[prec]) == NULL)
150 cd->cd_order[prec] = cd->cd_ordp++;
151
152 /*
153 * Reset cd_qualp to the highest precedence level that we've seen so
154 * far that can be qualified (CTF_PREC_BASE or CTF_PREC_POINTER).
155 */
156 if (prec > cd->cd_qualp && prec < CTF_PREC_ARRAY)
157 cd->cd_qualp = prec;
158
159 /*
160 * C array declarators are ordered inside out so prepend them. Also by
161 * convention qualifiers of base types precede the type specifier (e.g.
162 * const int vs. int const) even though the two forms are equivalent.
163 */
164 if (kind == CTF_K_ARRAY || (is_qual && prec == CTF_PREC_BASE))
165 ctf_list_prepend(&cd->cd_nodes[prec], cdp);
166 else
167 ctf_list_append(&cd->cd_nodes[prec], cdp);
168 }
169
170 /*PRINTFLIKE2*/
171 void
ctf_decl_sprintf(ctf_decl_t * cd,const char * format,...)172 ctf_decl_sprintf(ctf_decl_t *cd, const char *format, ...)
173 {
174 size_t len = (size_t)(cd->cd_end - cd->cd_ptr);
175 va_list ap;
176 size_t n;
177
178 va_start(ap, format);
179 n = vsnprintf(cd->cd_ptr, len, format, ap);
180 va_end(ap);
181
182 cd->cd_ptr += MIN(n, len);
183 cd->cd_len += n;
184 }
185