GDB (xrefs)

strfns.py
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1 # Useful gdb string convenience functions.
2 # Copyright (C) 2012-2018 Free Software Foundation, Inc.
3
4 # This program is free software; you can redistribute it and/or modify
5 # it under the terms of the GNU General Public License as published by
6 # the Free Software Foundation; either version 3 of the License, or
7 # (at your option) any later version.
8 #
9 # This program is distributed in the hope that it will be useful,
10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 # GNU General Public License for more details.
13 #
14 # You should have received a copy of the GNU General Public License
15 # along with this program. If not, see <http://www.gnu.org/licenses/>.
16
17 """$_memeq, $_strlen, $_streq, $_regex"""
18
19 import gdb
20 import re
21
22
23 class _MemEq(gdb.Function):
24 """$_memeq - compare bytes of memory
25
26 Usage:
27 $_memeq(a, b, len)
28
29 Returns:
30 True if len bytes at a and b compare equally.
31 """
32 def __init__(self):
33 super(_MemEq, self).__init__("_memeq")
34
35 def invoke(self, a, b, length):
36 if length < 0:
37 raise ValueError("length must be non-negative")
38 if length == 0:
39 return True
40 # The argument(s) to vector are [low_bound,]high_bound.
41 byte_vector = gdb.lookup_type("char").vector(length - 1)
42 ptr_byte_vector = byte_vector.pointer()
43 a_ptr = a.reinterpret_cast(ptr_byte_vector)
44 b_ptr = b.reinterpret_cast(ptr_byte_vector)
45 return a_ptr.dereference() == b_ptr.dereference()
46
47
48 class _StrLen(gdb.Function):
49 """$_strlen - compute string length
50
51 Usage:
52 $_strlen(a)
53
54 Returns:
55 Length of string a, assumed to be a string in the current language.
56 """
57 def __init__(self):
58 super(_StrLen, self).__init__("_strlen")
59
60 def invoke(self, a):
61 s = a.string()
62 return len(s)
63
64
65 class _StrEq(gdb.Function):
66 """$_streq - check string equality
67
68 Usage:
69 $_streq(a, b)
70
71 Returns:
72 True if a and b are identical strings in the current language.
73
74 Example (amd64-linux):
75 catch syscall open
76 cond $bpnum $_streq((char*) $rdi, "foo")
77 """
78 def __init__(self):
79 super(_StrEq, self).__init__("_streq")
80
81 def invoke(self, a, b):
82 return a.string() == b.string()
83
84
85 class _RegEx(gdb.Function):
86 """$_regex - check if a string matches a regular expression
87
88 Usage:
89 $_regex(string, regex)
90
91 Returns:
92 True if string str (in the current language) matches the
93 regular expression regex.
94 """
95 def __init__(self):
96 super(_RegEx, self).__init__("_regex")
97
98 def invoke(self, string, regex):
99 s = string.string()
100 r = re.compile(regex.string())
101 return bool(r.match(s))
102
103
104 # GDB will import us automagically via gdb/__init__.py.
105 _MemEq()
106 _StrLen()
107 _StrEq()
108 _RegEx()
gdb.function.strfns._StrLen.__init__
def __init__(self)
Definition: strfns.py:57
gdb.function.strfns._MemEq.__init__
def __init__(self)
Definition: strfns.py:32
gdb.function.strfns._MemEq
Definition: strfns.py:23
gdb.function.strfns._StrLen
Definition: strfns.py:48
gdb.function.strfns._RegEx.__init__
def __init__(self)
Definition: strfns.py:95
gdb.function.strfns._StrEq.__init__
def __init__(self)
Definition: strfns.py:78
gdb.function.strfns._RegEx.invoke
def invoke(self, string, regex)
Definition: strfns.py:98
gdb.function.strfns._StrLen.invoke
def invoke(self, a)
Definition: strfns.py:60
gdb.function.strfns._StrEq.invoke
def invoke(self, a, b)
Definition: strfns.py:81
gdb.function.strfns._RegEx
Definition: strfns.py:85
gdb.function.strfns._MemEq.invoke
def invoke(self, a, b, length)
Definition: strfns.py:35
gdb.function.strfns._StrEq
Definition: strfns.py:65