1c91eb033SWilly Tarreau /* SPDX-License-Identifier: LGPL-2.1 OR MIT */
2c91eb033SWilly Tarreau /*
3c91eb033SWilly Tarreau * string function definitions for NOLIBC
4c91eb033SWilly Tarreau * Copyright (C) 2017-2021 Willy Tarreau <w@1wt.eu>
5c91eb033SWilly Tarreau */
6c91eb033SWilly Tarreau
7c91eb033SWilly Tarreau #ifndef _NOLIBC_STRING_H
8c91eb033SWilly Tarreau #define _NOLIBC_STRING_H
9c91eb033SWilly Tarreau
10c91eb033SWilly Tarreau #include "std.h"
11c91eb033SWilly Tarreau
1211dbdaefSAmmar Faizi static void *malloc(size_t len);
1311dbdaefSAmmar Faizi
14c91eb033SWilly Tarreau /*
15c91eb033SWilly Tarreau * As much as possible, please keep functions alphabetically sorted.
16c91eb033SWilly Tarreau */
17c91eb033SWilly Tarreau
18c91eb033SWilly Tarreau static __attribute__((unused))
memcmp(const void * s1,const void * s2,size_t n)19c91eb033SWilly Tarreau int memcmp(const void *s1, const void *s2, size_t n)
20c91eb033SWilly Tarreau {
21c91eb033SWilly Tarreau size_t ofs = 0;
22b3f4f51eSRasmus Villemoes int c1 = 0;
23c91eb033SWilly Tarreau
24b3f4f51eSRasmus Villemoes while (ofs < n && !(c1 = ((unsigned char *)s1)[ofs] - ((unsigned char *)s2)[ofs])) {
25c91eb033SWilly Tarreau ofs++;
26c91eb033SWilly Tarreau }
27c91eb033SWilly Tarreau return c1;
28c91eb033SWilly Tarreau }
29c91eb033SWilly Tarreau
30c91eb033SWilly Tarreau static __attribute__((unused))
_nolibc_memcpy_up(void * dst,const void * src,size_t len)31d8dcc2d8SWilly Tarreau void *_nolibc_memcpy_up(void *dst, const void *src, size_t len)
32d8dcc2d8SWilly Tarreau {
33d8dcc2d8SWilly Tarreau size_t pos = 0;
34d8dcc2d8SWilly Tarreau
35d8dcc2d8SWilly Tarreau while (pos < len) {
36d8dcc2d8SWilly Tarreau ((char *)dst)[pos] = ((const char *)src)[pos];
37d8dcc2d8SWilly Tarreau pos++;
38d8dcc2d8SWilly Tarreau }
39d8dcc2d8SWilly Tarreau return dst;
40d8dcc2d8SWilly Tarreau }
41d8dcc2d8SWilly Tarreau
42d8dcc2d8SWilly Tarreau static __attribute__((unused))
_nolibc_memcpy_down(void * dst,const void * src,size_t len)43d8dcc2d8SWilly Tarreau void *_nolibc_memcpy_down(void *dst, const void *src, size_t len)
44d8dcc2d8SWilly Tarreau {
45d8dcc2d8SWilly Tarreau while (len) {
46d8dcc2d8SWilly Tarreau len--;
47d8dcc2d8SWilly Tarreau ((char *)dst)[len] = ((const char *)src)[len];
48d8dcc2d8SWilly Tarreau }
49d8dcc2d8SWilly Tarreau return dst;
50d8dcc2d8SWilly Tarreau }
51d8dcc2d8SWilly Tarreau
528d304a37SWilly Tarreau /* might be ignored by the compiler without -ffreestanding, then found as
538d304a37SWilly Tarreau * missing.
548d304a37SWilly Tarreau */
558d304a37SWilly Tarreau __attribute__((weak,unused,section(".text.nolibc_memmove")))
memmove(void * dst,const void * src,size_t len)56c91eb033SWilly Tarreau void *memmove(void *dst, const void *src, size_t len)
57c91eb033SWilly Tarreau {
58d76232ffSWilly Tarreau size_t dir, pos;
59c91eb033SWilly Tarreau
60d76232ffSWilly Tarreau pos = len;
61d76232ffSWilly Tarreau dir = -1;
62d76232ffSWilly Tarreau
63d76232ffSWilly Tarreau if (dst < src) {
64d76232ffSWilly Tarreau pos = -1;
65d76232ffSWilly Tarreau dir = 1;
66c91eb033SWilly Tarreau }
67d76232ffSWilly Tarreau
68d76232ffSWilly Tarreau while (len) {
69d76232ffSWilly Tarreau pos += dir;
70d76232ffSWilly Tarreau ((char *)dst)[pos] = ((const char *)src)[pos];
71d76232ffSWilly Tarreau len--;
72d76232ffSWilly Tarreau }
73d76232ffSWilly Tarreau return dst;
74c91eb033SWilly Tarreau }
75c91eb033SWilly Tarreau
76c91eb033SWilly Tarreau /* must be exported, as it's used by libgcc on ARM */
7707f47ea0SWilly Tarreau __attribute__((weak,unused,section(".text.nolibc_memcpy")))
memcpy(void * dst,const void * src,size_t len)78c91eb033SWilly Tarreau void *memcpy(void *dst, const void *src, size_t len)
79c91eb033SWilly Tarreau {
80d8dcc2d8SWilly Tarreau return _nolibc_memcpy_up(dst, src, len);
81c91eb033SWilly Tarreau }
82c91eb033SWilly Tarreau
838d304a37SWilly Tarreau /* might be ignored by the compiler without -ffreestanding, then found as
848d304a37SWilly Tarreau * missing.
858d304a37SWilly Tarreau */
868d304a37SWilly Tarreau __attribute__((weak,unused,section(".text.nolibc_memset")))
memset(void * dst,int b,size_t len)87c91eb033SWilly Tarreau void *memset(void *dst, int b, size_t len)
88c91eb033SWilly Tarreau {
89c91eb033SWilly Tarreau char *p = dst;
90c91eb033SWilly Tarreau
911bfbe1f3SWilly Tarreau while (len--) {
921bfbe1f3SWilly Tarreau /* prevent gcc from recognizing memset() here */
93*7f291cfaSThomas Weißschuh __asm__ volatile("");
94c91eb033SWilly Tarreau *(p++) = b;
951bfbe1f3SWilly Tarreau }
96c91eb033SWilly Tarreau return dst;
97c91eb033SWilly Tarreau }
98c91eb033SWilly Tarreau
99c91eb033SWilly Tarreau static __attribute__((unused))
strchr(const char * s,int c)100c91eb033SWilly Tarreau char *strchr(const char *s, int c)
101c91eb033SWilly Tarreau {
102c91eb033SWilly Tarreau while (*s) {
103c91eb033SWilly Tarreau if (*s == (char)c)
104c91eb033SWilly Tarreau return (char *)s;
105c91eb033SWilly Tarreau s++;
106c91eb033SWilly Tarreau }
107c91eb033SWilly Tarreau return NULL;
108c91eb033SWilly Tarreau }
109c91eb033SWilly Tarreau
110c91eb033SWilly Tarreau static __attribute__((unused))
strcmp(const char * a,const char * b)1110e7b4929SWilly Tarreau int strcmp(const char *a, const char *b)
1120e7b4929SWilly Tarreau {
1130e7b4929SWilly Tarreau unsigned int c;
1140e7b4929SWilly Tarreau int diff;
1150e7b4929SWilly Tarreau
1160e7b4929SWilly Tarreau while (!(diff = (unsigned char)*a++ - (c = (unsigned char)*b++)) && c)
1170e7b4929SWilly Tarreau ;
1180e7b4929SWilly Tarreau return diff;
1190e7b4929SWilly Tarreau }
1200e7b4929SWilly Tarreau
1210e7b4929SWilly Tarreau static __attribute__((unused))
strcpy(char * dst,const char * src)122c91eb033SWilly Tarreau char *strcpy(char *dst, const char *src)
123c91eb033SWilly Tarreau {
124c91eb033SWilly Tarreau char *ret = dst;
125c91eb033SWilly Tarreau
126c91eb033SWilly Tarreau while ((*dst++ = *src++));
127c91eb033SWilly Tarreau return ret;
128c91eb033SWilly Tarreau }
129c91eb033SWilly Tarreau
13096980b83SWilly Tarreau /* this function is only used with arguments that are not constants or when
131bfc3b0f0SWilly Tarreau * it's not known because optimizations are disabled. Note that gcc 12
132bfc3b0f0SWilly Tarreau * recognizes an strlen() pattern and replaces it with a jump to strlen(),
133bfc3b0f0SWilly Tarreau * thus itself, hence the asm() statement below that's meant to disable this
134bfc3b0f0SWilly Tarreau * confusing practice.
13596980b83SWilly Tarreau */
136c91eb033SWilly Tarreau static __attribute__((unused))
strlen(const char * str)137bfc3b0f0SWilly Tarreau size_t strlen(const char *str)
138c91eb033SWilly Tarreau {
139c91eb033SWilly Tarreau size_t len;
140c91eb033SWilly Tarreau
141bfc3b0f0SWilly Tarreau for (len = 0; str[len]; len++)
142*7f291cfaSThomas Weißschuh __asm__("");
143c91eb033SWilly Tarreau return len;
144c91eb033SWilly Tarreau }
145c91eb033SWilly Tarreau
14696980b83SWilly Tarreau /* do not trust __builtin_constant_p() at -O0, as clang will emit a test and
14796980b83SWilly Tarreau * the two branches, then will rely on an external definition of strlen().
14896980b83SWilly Tarreau */
14996980b83SWilly Tarreau #if defined(__OPTIMIZE__)
150bfc3b0f0SWilly Tarreau #define nolibc_strlen(x) strlen(x)
151c91eb033SWilly Tarreau #define strlen(str) ({ \
152c91eb033SWilly Tarreau __builtin_constant_p((str)) ? \
153c91eb033SWilly Tarreau __builtin_strlen((str)) : \
154c91eb033SWilly Tarreau nolibc_strlen((str)); \
155c91eb033SWilly Tarreau })
15696980b83SWilly Tarreau #endif
157c91eb033SWilly Tarreau
158c91eb033SWilly Tarreau static __attribute__((unused))
strnlen(const char * str,size_t maxlen)159b26823c1SAmmar Faizi size_t strnlen(const char *str, size_t maxlen)
160b26823c1SAmmar Faizi {
161b26823c1SAmmar Faizi size_t len;
162b26823c1SAmmar Faizi
163b26823c1SAmmar Faizi for (len = 0; (len < maxlen) && str[len]; len++);
164b26823c1SAmmar Faizi return len;
165b26823c1SAmmar Faizi }
166b26823c1SAmmar Faizi
167b26823c1SAmmar Faizi static __attribute__((unused))
strdup(const char * str)16811dbdaefSAmmar Faizi char *strdup(const char *str)
16911dbdaefSAmmar Faizi {
17011dbdaefSAmmar Faizi size_t len;
17111dbdaefSAmmar Faizi char *ret;
17211dbdaefSAmmar Faizi
17311dbdaefSAmmar Faizi len = strlen(str);
17411dbdaefSAmmar Faizi ret = malloc(len + 1);
17511dbdaefSAmmar Faizi if (__builtin_expect(ret != NULL, 1))
17611dbdaefSAmmar Faizi memcpy(ret, str, len + 1);
17711dbdaefSAmmar Faizi
17811dbdaefSAmmar Faizi return ret;
17911dbdaefSAmmar Faizi }
18011dbdaefSAmmar Faizi
18111dbdaefSAmmar Faizi static __attribute__((unused))
strndup(const char * str,size_t maxlen)18211dbdaefSAmmar Faizi char *strndup(const char *str, size_t maxlen)
18311dbdaefSAmmar Faizi {
18411dbdaefSAmmar Faizi size_t len;
18511dbdaefSAmmar Faizi char *ret;
18611dbdaefSAmmar Faizi
18711dbdaefSAmmar Faizi len = strnlen(str, maxlen);
18811dbdaefSAmmar Faizi ret = malloc(len + 1);
18911dbdaefSAmmar Faizi if (__builtin_expect(ret != NULL, 1)) {
19011dbdaefSAmmar Faizi memcpy(ret, str, len);
19111dbdaefSAmmar Faizi ret[len] = '\0';
19211dbdaefSAmmar Faizi }
19311dbdaefSAmmar Faizi
19411dbdaefSAmmar Faizi return ret;
19511dbdaefSAmmar Faizi }
19611dbdaefSAmmar Faizi
19711dbdaefSAmmar Faizi static __attribute__((unused))
strlcat(char * dst,const char * src,size_t size)198d9390de6SWilly Tarreau size_t strlcat(char *dst, const char *src, size_t size)
199d9390de6SWilly Tarreau {
200d9390de6SWilly Tarreau size_t len;
201d9390de6SWilly Tarreau char c;
202d9390de6SWilly Tarreau
203d9390de6SWilly Tarreau for (len = 0; dst[len]; len++)
204d9390de6SWilly Tarreau ;
205d9390de6SWilly Tarreau
206d9390de6SWilly Tarreau for (;;) {
207d9390de6SWilly Tarreau c = *src;
208d9390de6SWilly Tarreau if (len < size)
209d9390de6SWilly Tarreau dst[len] = c;
210d9390de6SWilly Tarreau if (!c)
211d9390de6SWilly Tarreau break;
212d9390de6SWilly Tarreau len++;
213d9390de6SWilly Tarreau src++;
214d9390de6SWilly Tarreau }
215d9390de6SWilly Tarreau
216d9390de6SWilly Tarreau return len;
217d9390de6SWilly Tarreau }
218d9390de6SWilly Tarreau
219d9390de6SWilly Tarreau static __attribute__((unused))
strlcpy(char * dst,const char * src,size_t size)220b312eb0bSWilly Tarreau size_t strlcpy(char *dst, const char *src, size_t size)
221b312eb0bSWilly Tarreau {
222b312eb0bSWilly Tarreau size_t len;
223b312eb0bSWilly Tarreau char c;
224b312eb0bSWilly Tarreau
225b312eb0bSWilly Tarreau for (len = 0;;) {
226b312eb0bSWilly Tarreau c = src[len];
227b312eb0bSWilly Tarreau if (len < size)
228b312eb0bSWilly Tarreau dst[len] = c;
229b312eb0bSWilly Tarreau if (!c)
230b312eb0bSWilly Tarreau break;
231b312eb0bSWilly Tarreau len++;
232b312eb0bSWilly Tarreau }
233b312eb0bSWilly Tarreau return len;
234b312eb0bSWilly Tarreau }
235b312eb0bSWilly Tarreau
236b312eb0bSWilly Tarreau static __attribute__((unused))
strncat(char * dst,const char * src,size_t size)237d9390de6SWilly Tarreau char *strncat(char *dst, const char *src, size_t size)
238d9390de6SWilly Tarreau {
239d9390de6SWilly Tarreau char *orig = dst;
240d9390de6SWilly Tarreau
241d9390de6SWilly Tarreau while (*dst)
242d9390de6SWilly Tarreau dst++;
243d9390de6SWilly Tarreau
244d9390de6SWilly Tarreau while (size && (*dst = *src)) {
245d9390de6SWilly Tarreau src++;
246d9390de6SWilly Tarreau dst++;
247d9390de6SWilly Tarreau size--;
248d9390de6SWilly Tarreau }
249d9390de6SWilly Tarreau
250d9390de6SWilly Tarreau *dst = 0;
251d9390de6SWilly Tarreau return orig;
252d9390de6SWilly Tarreau }
253d9390de6SWilly Tarreau
2540e7b4929SWilly Tarreau static __attribute__((unused))
strncmp(const char * a,const char * b,size_t size)2550e7b4929SWilly Tarreau int strncmp(const char *a, const char *b, size_t size)
2560e7b4929SWilly Tarreau {
2570e7b4929SWilly Tarreau unsigned int c;
2580e7b4929SWilly Tarreau int diff = 0;
2590e7b4929SWilly Tarreau
2600e7b4929SWilly Tarreau while (size-- &&
2610e7b4929SWilly Tarreau !(diff = (unsigned char)*a++ - (c = (unsigned char)*b++)) && c)
2620e7b4929SWilly Tarreau ;
2630e7b4929SWilly Tarreau
2640e7b4929SWilly Tarreau return diff;
2650e7b4929SWilly Tarreau }
266d9390de6SWilly Tarreau
267d9390de6SWilly Tarreau static __attribute__((unused))
strncpy(char * dst,const char * src,size_t size)268b312eb0bSWilly Tarreau char *strncpy(char *dst, const char *src, size_t size)
269b312eb0bSWilly Tarreau {
270b312eb0bSWilly Tarreau size_t len;
271b312eb0bSWilly Tarreau
272b312eb0bSWilly Tarreau for (len = 0; len < size; len++)
273b312eb0bSWilly Tarreau if ((dst[len] = *src))
274b312eb0bSWilly Tarreau src++;
275b312eb0bSWilly Tarreau return dst;
276b312eb0bSWilly Tarreau }
277b312eb0bSWilly Tarreau
278b312eb0bSWilly Tarreau static __attribute__((unused))
strrchr(const char * s,int c)279c91eb033SWilly Tarreau char *strrchr(const char *s, int c)
280c91eb033SWilly Tarreau {
281c91eb033SWilly Tarreau const char *ret = NULL;
282c91eb033SWilly Tarreau
283c91eb033SWilly Tarreau while (*s) {
284c91eb033SWilly Tarreau if (*s == (char)c)
285c91eb033SWilly Tarreau ret = s;
286c91eb033SWilly Tarreau s++;
287c91eb033SWilly Tarreau }
288c91eb033SWilly Tarreau return (char *)ret;
289c91eb033SWilly Tarreau }
290c91eb033SWilly Tarreau
29155abdd1fSWilly Tarreau /* make sure to include all global symbols */
29255abdd1fSWilly Tarreau #include "nolibc.h"
29355abdd1fSWilly Tarreau
294c91eb033SWilly Tarreau #endif /* _NOLIBC_STRING_H */
295