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