xref: /freebsd/contrib/elftoolchain/libdwarf/libdwarf_loclist.c (revision 3b8f08459569bf0faa21473e5cec2491e95c9349)
1 /*-
2  * Copyright (c) 2009,2011 Kai Wang
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include "_libdwarf.h"
28 
29 ELFTC_VCSID("$Id: libdwarf_loclist.c 2972 2013-12-23 06:46:04Z kaiwang27 $");
30 
31 static int
32 _dwarf_loclist_add_locdesc(Dwarf_Debug dbg, Dwarf_CU cu, Dwarf_Section *ds,
33     uint64_t *off, Dwarf_Locdesc **ld, uint64_t *ldlen,
34     Dwarf_Unsigned *total_len, Dwarf_Error *error)
35 {
36 	uint64_t start, end;
37 	int i, len, ret;
38 
39 	if (total_len != NULL)
40 		*total_len = 0;
41 
42 	for (i = 0; *off < ds->ds_size; i++) {
43 		start = dbg->read(ds->ds_data, off, cu->cu_pointer_size);
44 		end = dbg->read(ds->ds_data, off, cu->cu_pointer_size);
45 		if (ld != NULL) {
46 			ld[i]->ld_lopc = start;
47 			ld[i]->ld_hipc = end;
48 		}
49 
50 		if (total_len != NULL)
51 			*total_len += 2 * cu->cu_pointer_size;
52 
53 		/* Check if it is the end entry. */
54 		if (start == 0 && end ==0) {
55 			i++;
56 			break;
57 		}
58 
59 		/* Check if it is base-select entry. */
60 		if ((cu->cu_pointer_size == 4 && start == ~0U) ||
61 		    (cu->cu_pointer_size == 8 && start == ~0ULL))
62 			continue;
63 
64 		/* Otherwise it's normal entry. */
65 		len = dbg->read(ds->ds_data, off, 2);
66 		if (*off + len > ds->ds_size) {
67 			DWARF_SET_ERROR(dbg, error,
68 			    DW_DLE_DEBUG_LOC_SECTION_SHORT);
69 			return (DW_DLE_DEBUG_LOC_SECTION_SHORT);
70 		}
71 
72 		if (total_len != NULL)
73 			*total_len += len;
74 
75 		if (ld != NULL) {
76 			ret = _dwarf_loc_fill_locdesc(dbg, ld[i],
77 			    ds->ds_data + *off, len, cu->cu_pointer_size,
78 			    error);
79 			if (ret != DW_DLE_NONE)
80 				return (ret);
81 		}
82 
83 		*off += len;
84 	}
85 
86 	if (ldlen != NULL)
87 		*ldlen = i;
88 
89 	return (DW_DLE_NONE);
90 }
91 
92 int
93 _dwarf_loclist_find(Dwarf_Debug dbg, Dwarf_CU cu, uint64_t lloff,
94     Dwarf_Loclist *ret_ll, Dwarf_Error *error)
95 {
96 	Dwarf_Loclist ll;
97 	int ret;
98 
99 	assert(ret_ll != NULL);
100 	ret = DW_DLE_NONE;
101 
102 	TAILQ_FOREACH(ll, &dbg->dbg_loclist, ll_next)
103 		if (ll->ll_offset == lloff)
104 			break;
105 
106 	if (ll == NULL)
107 		ret = _dwarf_loclist_add(dbg, cu, lloff, ret_ll, error);
108 	else
109 		*ret_ll = ll;
110 
111 	return (ret);
112 }
113 
114 int
115 _dwarf_loclist_add(Dwarf_Debug dbg, Dwarf_CU cu, uint64_t lloff,
116     Dwarf_Loclist *ret_ll, Dwarf_Error *error)
117 {
118 	Dwarf_Section *ds;
119 	Dwarf_Loclist ll, tll;
120 	uint64_t ldlen;
121 	int i, ret;
122 
123 	ret = DW_DLE_NONE;
124 
125 	if ((ds = _dwarf_find_section(dbg, ".debug_loc")) == NULL) {
126 		DWARF_SET_ERROR(dbg, error, DW_DLE_NO_ENTRY);
127 		return (DW_DLE_NO_ENTRY);
128 	}
129 
130 	if (lloff >= ds->ds_size) {
131 		DWARF_SET_ERROR(dbg, error, DW_DLE_NO_ENTRY);
132 		return (DW_DLE_NO_ENTRY);
133 	}
134 
135 	if ((ll = malloc(sizeof(struct _Dwarf_Loclist))) == NULL) {
136 		DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY);
137 		return (DW_DLE_MEMORY);
138 	}
139 
140 	ll->ll_offset = lloff;
141 
142 	/* Get the number of locdesc the first round. */
143 	ret = _dwarf_loclist_add_locdesc(dbg, cu, ds, &lloff, NULL, &ldlen,
144 	    NULL, error);
145 	if (ret != DW_DLE_NONE)
146 		goto fail_cleanup;
147 
148 	/*
149 	 * Dwarf_Locdesc list memory is allocated in this way (one more level
150 	 * of indirect) to make the loclist API be compatible with SGI libdwarf.
151 	 */
152 	ll->ll_ldlen = ldlen;
153 	if (ldlen != 0) {
154 		if ((ll->ll_ldlist = calloc(ldlen, sizeof(Dwarf_Locdesc *))) ==
155 		    NULL) {
156 			DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY);
157 			ret = DW_DLE_MEMORY;
158 			goto fail_cleanup;
159 		}
160 		for (i = 0; (uint64_t) i < ldlen; i++) {
161 			if ((ll->ll_ldlist[i] =
162 			    calloc(1, sizeof(Dwarf_Locdesc))) == NULL) {
163 				DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY);
164 				ret = DW_DLE_MEMORY;
165 				goto fail_cleanup;
166 			}
167 		}
168 	} else
169 		ll->ll_ldlist = NULL;
170 
171 	lloff = ll->ll_offset;
172 
173 	/* Fill in locdesc. */
174 	ret = _dwarf_loclist_add_locdesc(dbg, cu, ds, &lloff, ll->ll_ldlist,
175 	    NULL, &ll->ll_length, error);
176 	if (ret != DW_DLE_NONE)
177 		goto fail_cleanup;
178 
179 	/* Insert to the queue. Sort by offset. */
180 	TAILQ_FOREACH(tll, &dbg->dbg_loclist, ll_next)
181 		if (tll->ll_offset > ll->ll_offset) {
182 			TAILQ_INSERT_BEFORE(tll, ll, ll_next);
183 			break;
184 		}
185 
186 	if (tll == NULL)
187 		TAILQ_INSERT_TAIL(&dbg->dbg_loclist, ll, ll_next);
188 
189 	*ret_ll = ll;
190 	return (DW_DLE_NONE);
191 
192 fail_cleanup:
193 
194 	_dwarf_loclist_free(ll);
195 
196 	return (ret);
197 }
198 
199 void
200 _dwarf_loclist_free(Dwarf_Loclist ll)
201 {
202 	int i;
203 
204 	if (ll == NULL)
205 		return;
206 
207 	if (ll->ll_ldlist != NULL) {
208 		for (i = 0; i < ll->ll_ldlen; i++) {
209 			if (ll->ll_ldlist[i]->ld_s)
210 				free(ll->ll_ldlist[i]->ld_s);
211 			free(ll->ll_ldlist[i]);
212 		}
213 		free(ll->ll_ldlist);
214 	}
215 	free(ll);
216 }
217 
218 void
219 _dwarf_loclist_cleanup(Dwarf_Debug dbg)
220 {
221 	Dwarf_Loclist ll, tll;
222 
223 	assert(dbg != NULL && dbg->dbg_mode == DW_DLC_READ);
224 
225 	TAILQ_FOREACH_SAFE(ll, &dbg->dbg_loclist, ll_next, tll) {
226 		TAILQ_REMOVE(&dbg->dbg_loclist, ll, ll_next);
227 		_dwarf_loclist_free(ll);
228 	}
229 }
230