tools/nolibc/string: Implement `strdup()` and `strndup()`

These functions are currently only available on architectures that have
my_syscall6() macro implemented. Since these functions use malloc(),
malloc() uses mmap(), mmap() depends on my_syscall6() macro.

On architectures that don't support my_syscall6(), these function will
always return NULL with errno set to ENOSYS.

Acked-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit is contained in:
Ammar Faizi 2022-03-29 17:17:37 +07:00 committed by Paul E. McKenney
parent b26823c19a
commit 11dbdaeff4
1 changed files with 32 additions and 0 deletions

View File

@ -9,6 +9,8 @@
#include "std.h"
static void *malloc(size_t len);
/*
* As much as possible, please keep functions alphabetically sorted.
*/
@ -156,6 +158,36 @@ size_t strnlen(const char *str, size_t maxlen)
return len;
}
static __attribute__((unused))
char *strdup(const char *str)
{
size_t len;
char *ret;
len = strlen(str);
ret = malloc(len + 1);
if (__builtin_expect(ret != NULL, 1))
memcpy(ret, str, len + 1);
return ret;
}
static __attribute__((unused))
char *strndup(const char *str, size_t maxlen)
{
size_t len;
char *ret;
len = strnlen(str, maxlen);
ret = malloc(len + 1);
if (__builtin_expect(ret != NULL, 1)) {
memcpy(ret, str, len);
ret[len] = '\0';
}
return ret;
}
static __attribute__((unused))
size_t strlcat(char *dst, const char *src, size_t size)
{