xref: /aosp_15_r20/external/llvm-libc/src/string/strspn.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1*71db0c75SAndroid Build Coastguard Worker //===-- Implementation of strspn ------------------------------------------===//
2*71db0c75SAndroid Build Coastguard Worker //
3*71db0c75SAndroid Build Coastguard Worker // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*71db0c75SAndroid Build Coastguard Worker // See https://llvm.org/LICENSE.txt for license information.
5*71db0c75SAndroid Build Coastguard Worker // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*71db0c75SAndroid Build Coastguard Worker //
7*71db0c75SAndroid Build Coastguard Worker //===----------------------------------------------------------------------===//
8*71db0c75SAndroid Build Coastguard Worker 
9*71db0c75SAndroid Build Coastguard Worker #include "src/string/strspn.h"
10*71db0c75SAndroid Build Coastguard Worker 
11*71db0c75SAndroid Build Coastguard Worker #include "src/__support/CPP/bitset.h"
12*71db0c75SAndroid Build Coastguard Worker #include "src/__support/common.h"
13*71db0c75SAndroid Build Coastguard Worker #include "src/__support/macros/config.h"
14*71db0c75SAndroid Build Coastguard Worker #include <stddef.h>
15*71db0c75SAndroid Build Coastguard Worker 
16*71db0c75SAndroid Build Coastguard Worker namespace LIBC_NAMESPACE_DECL {
17*71db0c75SAndroid Build Coastguard Worker 
18*71db0c75SAndroid Build Coastguard Worker LLVM_LIBC_FUNCTION(size_t, strspn, (const char *src, const char *segment)) {
19*71db0c75SAndroid Build Coastguard Worker   const char *initial = src;
20*71db0c75SAndroid Build Coastguard Worker   cpp::bitset<256> bitset;
21*71db0c75SAndroid Build Coastguard Worker 
22*71db0c75SAndroid Build Coastguard Worker   for (; *segment; ++segment)
23*71db0c75SAndroid Build Coastguard Worker     bitset.set(*reinterpret_cast<const unsigned char *>(segment));
24*71db0c75SAndroid Build Coastguard Worker   for (; *src && bitset.test(*reinterpret_cast<const unsigned char *>(src));
25*71db0c75SAndroid Build Coastguard Worker        ++src)
26*71db0c75SAndroid Build Coastguard Worker     ;
27*71db0c75SAndroid Build Coastguard Worker   return src - initial;
28*71db0c75SAndroid Build Coastguard Worker }
29*71db0c75SAndroid Build Coastguard Worker 
30*71db0c75SAndroid Build Coastguard Worker } // namespace LIBC_NAMESPACE_DECL
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