1 /* Find CU for given offset.
2 Copyright (C) 2003, 2004 Red Hat, Inc.
3 Written by Ulrich Drepper <drepper@redhat.com>, 2003.
4
5 This program is Open Source software; you can redistribute it and/or
6 modify it under the terms of the Open Software License version 1.0 as
7 published by the Open Source Initiative.
8
9 You should have received a copy of the Open Software License along
10 with this program; if not, you may obtain a copy of the Open Software
11 License version 1.0 from http://www.opensource.org/licenses/osl.php or
12 by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
13 3001 King Ranch Road, Ukiah, CA 95482. */
14
15 #ifdef HAVE_CONFIG_H
16 # include <config.h>
17 #endif
18
19 #include <assert.h>
20 #include <search.h>
21 #include "libdwP.h"
22
23
24 static int
findcu_cb(const void * arg1,const void * arg2)25 findcu_cb (const void *arg1, const void *arg2)
26 {
27 struct Dwarf_CU *cu1 = (struct Dwarf_CU *) arg1;
28 struct Dwarf_CU *cu2 = (struct Dwarf_CU *) arg2;
29
30 /* Find out which of the two arguments is the search value. It has
31 end offset 0. */
32 if (cu1->end == 0)
33 {
34 if (cu1->start < cu2->start)
35 return -1;
36 if (cu1->start >= cu2->end)
37 return 1;
38 }
39 else
40 {
41 if (cu2->start < cu1->start)
42 return 1;
43 if (cu2->start >= cu1->end)
44 return -1;
45 }
46
47 return 0;
48 }
49
50
51 struct Dwarf_CU *
__libdw_findcu(dbg,start)52 __libdw_findcu (dbg, start)
53 Dwarf *dbg;
54 Dwarf_Off start;
55 {
56 /* Maybe we already know that CU. */
57 struct Dwarf_CU fake = { .start = start, .end = 0 };
58 struct Dwarf_CU **found = tfind (&fake, &dbg->cu_tree, findcu_cb);
59 if (found != NULL)
60 return *found;
61
62 if (start < dbg->next_cu_offset)
63 {
64 __libdw_seterrno (DWARF_E_INVALID_DWARF);
65 return NULL;
66 }
67
68 /* No. Then read more CUs. */
69 while (1)
70 {
71 Dwarf_Off oldoff = dbg->next_cu_offset;
72 uint8_t address_size;
73 uint8_t offset_size;
74 Dwarf_Off abbrev_offset;
75
76 if (dwarf_nextcu (dbg, oldoff, &dbg->next_cu_offset, NULL,
77 &abbrev_offset, &address_size, &offset_size) != 0)
78 /* No more entries. */
79 return NULL;
80
81 /* Create an entry for this CU. */
82 struct Dwarf_CU *newp = libdw_typed_alloc (dbg, struct Dwarf_CU);
83
84 newp->dbg = dbg;
85 newp->start = oldoff;
86 newp->end = dbg->next_cu_offset;
87 newp->address_size = address_size;
88 newp->offset_size = offset_size;
89 Dwarf_Abbrev_Hash_init (&newp->abbrev_hash, 41);
90 newp->orig_abbrev_offset = newp->last_abbrev_offset = abbrev_offset;
91 newp->lines = NULL;
92 newp->locs = NULL;
93
94 /* Add the new entry to the search tree. */
95 if (tsearch (newp, &dbg->cu_tree, findcu_cb) == NULL)
96 {
97 /* Something went wrong. Unfo the operation. */
98 dbg->next_cu_offset = oldoff;
99 __libdw_seterrno (DWARF_E_NOMEM);
100 return NULL;
101 }
102
103 /* Is this the one we are looking for? */
104 if (start < dbg->next_cu_offset)
105 // XXX Match exact offset.
106 return newp;
107 }
108 /* NOTREACHED */
109 }
110