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Diffstat (limited to 'firmware/common/strcasestr.c')
-rw-r--r--firmware/common/strcasestr.c122
1 files changed, 122 insertions, 0 deletions
diff --git a/firmware/common/strcasestr.c b/firmware/common/strcasestr.c
new file mode 100644
index 0000000000..095eebdd66
--- /dev/null
+++ b/firmware/common/strcasestr.c
@@ -0,0 +1,122 @@
1/* Return the offset of one string within another.
2 Copyright (C) 1994,1996,1997,1998,1999,2000 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA. */
19
20/*
21 * My personal strstr() implementation that beats most other algorithms.
22 * Until someone tells me otherwise, I assume that this is the
23 * fastest implementation of strstr() in C.
24 * I deliberately chose not to comment it. You should have at least
25 * as much fun trying to understand it, as I had to write it :-).
26 *
27 * Stephen R. van den Berg, berg@pool.informatik.rwth-aachen.de*/
28
29/* Faster looping by precalculating bl, bu, cl, cu before looping.
30 * 2004 Apr 08 Jose Da Silva, digital@joescat@com */
31
32#include <string.h>
33#include <ctype.h>
34
35typedef unsigned chartype;
36
37char* strcasestr (const char* phaystack, const char* pneedle)
38{
39 const unsigned char *haystack, *needle;
40 chartype bl, bu, cl, cu;
41
42 haystack = (const unsigned char *) phaystack;
43 needle = (const unsigned char *) pneedle;
44
45 bl = tolower (*needle);
46 if (bl != '\0')
47 {
48 bu = toupper (bl);
49 haystack--;/* possible ANSI violation */
50 do
51 {
52 cl = *++haystack;
53 if (cl == '\0')
54 goto ret0;
55 }
56 while ((cl != bl) && (cl != bu));
57
58 cl = tolower (*++needle);
59 if (cl == '\0')
60 goto foundneedle;
61 cu = toupper (cl);
62 ++needle;
63 goto jin;
64
65 for (;;)
66 {
67 chartype a;
68 const unsigned char *rhaystack, *rneedle;
69
70 do
71 {
72 a = *++haystack;
73 if (a == '\0')
74 goto ret0;
75 if ((a == bl) || (a == bu))
76 break;
77 a = *++haystack;
78 if (a == '\0')
79 goto ret0;
80 shloop:
81 ;
82 }
83 while ((a != bl) && (a != bu));
84
85 jin: a = *++haystack;
86 if (a == '\0')
87 goto ret0;
88
89 if ((a != cl) && (a != cu))
90 goto shloop;
91
92 rhaystack = haystack-- + 1;
93 rneedle = needle;
94 a = tolower (*rneedle);
95
96 if (tolower (*rhaystack) == (int) a)
97 do
98 {
99 if (a == '\0')
100 goto foundneedle;
101 ++rhaystack;
102 a = tolower (*++needle);
103 if (tolower (*rhaystack) != (int) a)
104 break;
105 if (a == '\0')
106 goto foundneedle;
107 ++rhaystack;
108 a = tolower (*++needle);
109 }
110 while (tolower (*rhaystack) == (int) a);
111
112 needle = rneedle;/* took the register-poor approach */
113
114 if (a == '\0')
115 break;
116 }
117 }
118 foundneedle:
119 return (char*) haystack;
120 ret0:
121 return 0;
122}