xref: /optee_os/lib/libutils/ext/include/string_ext.h (revision b7da54b3f039908dacf92a4719b9206ffc5644d3)
11bb92983SJerome Forissier /* SPDX-License-Identifier: BSD-2-Clause */
2b0104773SPascal Brand /*
3b0104773SPascal Brand  * Copyright (c) 2014, STMicroelectronics International N.V.
4b0104773SPascal Brand  */
5b0104773SPascal Brand 
6b0104773SPascal Brand /*
7b0104773SPascal Brand  * This file provides extensions for functions not defined in <string.h>
8b0104773SPascal Brand  */
9b0104773SPascal Brand 
10b0104773SPascal Brand #ifndef STRING_EXT_H
11b0104773SPascal Brand #define STRING_EXT_H
12b0104773SPascal Brand 
13b0104773SPascal Brand #include <stddef.h>
14b0104773SPascal Brand #include <sys/cdefs.h>
15b0104773SPascal Brand 
16b0104773SPascal Brand /*
17b0104773SPascal Brand  * Copy src to string dst of siz size.  At most siz-1 characters
18b0104773SPascal Brand  * will be copied.  Always NUL terminates (unless siz == 0).
19b0104773SPascal Brand  * Returns strlen(src); if retval >= siz, truncation occurred.
20b0104773SPascal Brand  */
21b0104773SPascal Brand size_t strlcpy(char *dst, const char *src, size_t size);
22b0104773SPascal Brand size_t strlcat(char *dst, const char *src, size_t size);
23b0104773SPascal Brand 
241665420cSJoakim Bech /*
251665420cSJoakim Bech  * This memory compare function will compare two buffers in a constant time.
261665420cSJoakim Bech  *
271665420cSJoakim Bech  * Note that this function will not have same kind of return values as the
281665420cSJoakim Bech  * traditional libc memcmp which return either less than or greater than zero
291665420cSJoakim Bech  * depending on which string that is lexically greater. This function will
301665420cSJoakim Bech  * return 0 if it is a match, otherwise it will return a non-zero value.
311665420cSJoakim Bech  */
321665420cSJoakim Bech int buf_compare_ct(const void *s1, const void *s2, size_t n);
331665420cSJoakim Bech 
34*b7da54b3SJerome Forissier /*
35*b7da54b3SJerome Forissier  * A constant-time version of memcmp(). Might be slightly slower than
36*b7da54b3SJerome Forissier  * buf_compare_ct(), but complies with the memcmp() specification which
37*b7da54b3SJerome Forissier  * requires three possible outcomes for the comparison (< 0, 0 and > 0).
38*b7da54b3SJerome Forissier  */
39*b7da54b3SJerome Forissier int consttime_memcmp(const void *p1, const void *p2, size_t nb);
40*b7da54b3SJerome Forissier 
411131d3c5SVolodymyr Babchuk /* Variant of strdup() that uses nex_malloc() instead of malloc() */
421131d3c5SVolodymyr Babchuk char *nex_strdup(const char *s);
431131d3c5SVolodymyr Babchuk 
44b0104773SPascal Brand #endif /* STRING_EXT_H */
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