1 | //===-- Implementation of lfind ---------------------------------*- C++ -*-===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | |
9 | #include "src/search/lfind.h" |
10 | #include "src/__support/CPP/cstddef.h" // cpp::byte |
11 | #include "src/__support/common.h" |
12 | #include "src/__support/macros/config.h" |
13 | #include "src/__support/memory_size.h" |
14 | |
15 | namespace LIBC_NAMESPACE_DECL { |
16 | LLVM_LIBC_FUNCTION(void *, lfind, |
17 | (const void *key, const void *base, size_t *nmemb, |
18 | size_t size, int (*compar)(const void *, const void *))) { |
19 | if (key == nullptr || base == nullptr || nmemb == nullptr || |
20 | compar == nullptr) |
21 | return nullptr; |
22 | |
23 | size_t byte_len = 0; |
24 | if (internal::mul_overflow(*nmemb, size, &byte_len)) |
25 | return nullptr; |
26 | |
27 | const cpp::byte *next = reinterpret_cast<const cpp::byte *>(base); |
28 | const cpp::byte *end = next + byte_len; |
29 | for (; next < end; next += size) |
30 | if (compar(key, next) == 0) |
31 | return const_cast<cpp::byte *>(next); |
32 | return nullptr; |
33 | } |
34 | |
35 | } // namespace LIBC_NAMESPACE_DECL |
36 | |