new: string.h

This commit is contained in:
fslongjin
2022-08-03 15:13:01 +08:00
parent aa7dc4daa5
commit d9ee6ea859
12 changed files with 191 additions and 120 deletions

View File

@ -1,31 +1,3 @@
#include "glib.h"
#include "string.h"
/**
* @brief 测量来自用户空间的字符串的长度,会检验地址空间是否属于用户空间
* @param src
* @param maxlen
* @return long
*/
long strnlen_user(const char *src, unsigned long maxlen)
{
unsigned long size = strlen(src);
// 地址不合法
if (!verify_area((uint64_t)src, size))
return 0;
return size <= maxlen ? size : maxlen;
}
long strnlen(const char *src, unsigned long maxlen)
{
if (src == NULL)
return 0;
register int __res = 0;
while (src[__res] != '\0' && __res < maxlen)
{
++__res;
}
return __res;
}