Line data Source code
1 : /* Add signed little endian base 128 integer to a section.
2 : Copyright (C) 2002, 2005 Red Hat, Inc.
3 : This file is part of elfutils.
4 : Written by Ulrich Drepper <drepper@redhat.com>, 2002.
5 :
6 : This file is free software; you can redistribute it and/or modify
7 : it under the terms of either
8 :
9 : * the GNU Lesser General Public License as published by the Free
10 : Software Foundation; either version 3 of the License, or (at
11 : your option) any later version
12 :
13 : or
14 :
15 : * the GNU General Public License as published by the Free
16 : Software Foundation; either version 2 of the License, or (at
17 : your option) any later version
18 :
19 : or both in parallel, as here.
20 :
21 : elfutils is distributed in the hope that it will be useful, but
22 : WITHOUT ANY WARRANTY; without even the implied warranty of
23 : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
24 : General Public License for more details.
25 :
26 : You should have received copies of the GNU General Public License and
27 : the GNU Lesser General Public License along with this program. If
28 : not, see <http://www.gnu.org/licenses/>. */
29 :
30 : #ifdef HAVE_CONFIG_H
31 : # include <config.h>
32 : #endif
33 :
34 : #include <inttypes.h>
35 : #include <string.h>
36 :
37 : #include <libasmP.h>
38 :
39 :
40 : int
41 16 : asm_addsleb128 (AsmScn_t *asmscn, int32_t num)
42 : {
43 16 : if (asmscn == NULL)
44 : return -1;
45 :
46 16 : if (asmscn->type == SHT_NOBITS && unlikely (num != 0))
47 : {
48 0 : __libasm_seterrno (ASM_E_TYPE);
49 0 : return -1;
50 : }
51 :
52 16 : if (unlikely (asmscn->ctx->textp))
53 0 : fprintf (asmscn->ctx->out.file, "\t.sleb128\t%" PRId32 "\n", num);
54 : else
55 : {
56 : char tmpbuf[(sizeof (num) * 8 + 6) / 7];
57 16 : char *dest = tmpbuf;
58 : uint32_t byte;
59 16 : int32_t endval = num >> 31;
60 :
61 16 : if (num == 0)
62 : byte = 0;
63 : else
64 : while (1)
65 : {
66 38 : byte = num & 0x7f;
67 :
68 38 : num >>= 7;
69 38 : if (num == endval)
70 : /* This is the last byte. */
71 : break;
72 :
73 24 : *dest++ = byte | 0x80;
74 24 : }
75 :
76 16 : *dest++ = byte;
77 :
78 : /* Number of bytes produced. */
79 16 : size_t nbytes = dest - tmpbuf;
80 :
81 : /* Make sure we have enough room. */
82 16 : if (__libasm_ensure_section_space (asmscn, nbytes) != 0)
83 0 : return -1;
84 :
85 : /* Copy the bytes. */
86 16 : if (likely (asmscn->type != SHT_NOBITS))
87 16 : memcpy (&asmscn->content->data[asmscn->content->len], tmpbuf, nbytes);
88 :
89 : /* Adjust the pointer in the data buffer. */
90 16 : asmscn->content->len += nbytes;
91 :
92 : /* Increment the offset in the (sub)section. */
93 16 : asmscn->offset += nbytes;
94 : }
95 :
96 : return 0;
97 : }
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