[PATCH 1/7] lib/string: add strnchrnul()
New function works like strchrnul() with a length limited strings.
Reviewed-by: Andy Shevchenko
Signed-off-by: Yury Norov
---
include/linux/string.h | 1 +
lib/string.c | 17 +
2 files changed, 18 insertions(+)
diff --git a/include/linux/string.h b/include/linux/string.h
index 3cf684db4bc6b..cf8f47efeb051 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -107,6 +107,7 @@ extern char * strchr(const char *,int);
#ifndef __HAVE_ARCH_STRCHRNUL
extern char * strchrnul(const char *,int);
#endif
+extern char * strnchrnul(const char *, size_t, int);
#ifndef __HAVE_ARCH_STRNCHR
extern char * strnchr(const char *, size_t, int);
#endif
diff --git a/lib/string.c b/lib/string.c
index cd7a10c192109..75b10363e61f0 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -434,6 +434,23 @@ char *strchrnul(const char *s, int c)
EXPORT_SYMBOL(strchrnul);
#endif
+/**
+ * strnchrnul - Find and return a character in a length limited string,
+ * or end of string
+ * @s: The string to be searched
+ * @count: The number of characters to be searched
+ * @c: The character to search for
+ *
+ * Returns pointer to the first occurrence of 'c' in s. If c is not found,
+ * then return a pointer to the last character of the string.
+ */
+char *strnchrnul(const char *s, size_t count, int c)
+{
+ while (count-- && *s && *s != (char)c)
+ s++;
+ return (char *)s;
+}
+
#ifndef __HAVE_ARCH_STRRCHR
/**
* strrchr - Find the last occurrence of a character in a string
--
2.20.1
[PATCH 1/7] lib/string: add strnchrnul()
>From Yury Norov
New function works like strchrnul() with a length limited strings.
Reviewed-by: Andy Shevchenko
Signed-off-by: Yury Norov
Signed-off-by: Yury Norov
---
include/linux/string.h | 1 +
lib/string.c | 17 +
2 files changed, 18 insertions(+)
diff --git a/include/linux/string.h b/include/linux/string.h
index 4deb11f7976bc..ae934d6c50bf5 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -62,6 +62,7 @@ extern char * strchr(const char *,int);
#ifndef __HAVE_ARCH_STRCHRNUL
extern char * strchrnul(const char *,int);
#endif
+extern char * strnchrnul(const char *, size_t, int);
#ifndef __HAVE_ARCH_STRNCHR
extern char * strnchr(const char *, size_t, int);
#endif
diff --git a/lib/string.c b/lib/string.c
index 461fb620f85f3..5b5fee266c193 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -432,6 +432,23 @@ char *strchrnul(const char *s, int c)
EXPORT_SYMBOL(strchrnul);
#endif
+/**
+ * strnchrnul - Find and return a character in a length limited string,
+ * or end of string
+ * @s: The string to be searched
+ * @count: The number of characters to be searched
+ * @c: The character to search for
+ *
+ * Returns pointer to the first occurrence of 'c' in s. If c is not found,
+ * then return a pointer to the last character of the string.
+ */
+char *strnchrnul(const char *s, size_t count, int c)
+{
+ while (count-- && *s && *s != (char)c)
+ s++;
+ return (char *)s;
+}
+
#ifndef __HAVE_ARCH_STRRCHR
/**
* strrchr - Find the last occurrence of a character in a string
--
2.20.1
Re: [PATCH 1/7] lib/string: add strnchrnul()
On Tue, Apr 30, 2019 at 06:06:30PM -0700, Yury Norov wrote:
> New function works like strchrnul() with a length limited strings.
>
Reviewed-by: Andy Shevchenko
> Signed-off-by: Yury Norov
> ---
> include/linux/string.h | 1 +
> lib/string.c | 17 +
> 2 files changed, 18 insertions(+)
>
> diff --git a/include/linux/string.h b/include/linux/string.h
> index 4deb11f7976b..ae934d6c50bf 100644
> --- a/include/linux/string.h
> +++ b/include/linux/string.h
> @@ -62,6 +62,7 @@ extern char * strchr(const char *,int);
> #ifndef __HAVE_ARCH_STRCHRNUL
> extern char * strchrnul(const char *,int);
> #endif
> +extern char * strnchrnul(const char *, size_t, int);
> #ifndef __HAVE_ARCH_STRNCHR
> extern char * strnchr(const char *, size_t, int);
> #endif
> diff --git a/lib/string.c b/lib/string.c
> index 6016eb3ac73d..eee521ad1f40 100644
> --- a/lib/string.c
> +++ b/lib/string.c
> @@ -429,6 +429,23 @@ char *strchrnul(const char *s, int c)
> EXPORT_SYMBOL(strchrnul);
> #endif
>
> +/**
> + * strnchrnul - Find and return a character in a length limited string,
> + * or end of string
> + * @s: The string to be searched
> + * @count: The number of characters to be searched
> + * @c: The character to search for
> + *
> + * Returns pointer to the first occurrence of 'c' in s. If c is not found,
> + * then return a pointer to the last character of the string.
> + */
> +char *strnchrnul(const char *s, size_t count, int c)
> +{
> + while (count-- && *s && *s != (char)c)
> + s++;
> + return (char *)s;
> +}
> +
> #ifndef __HAVE_ARCH_STRRCHR
> /**
> * strrchr - Find the last occurrence of a character in a string
> --
> 2.17.1
>
--
With Best Regards,
Andy Shevchenko
[PATCH 1/7] lib/string: add strnchrnul()
New function works like strchrnul() with a length limited strings.
Signed-off-by: Yury Norov
---
include/linux/string.h | 1 +
lib/string.c | 17 +
2 files changed, 18 insertions(+)
diff --git a/include/linux/string.h b/include/linux/string.h
index 4deb11f7976b..ae934d6c50bf 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -62,6 +62,7 @@ extern char * strchr(const char *,int);
#ifndef __HAVE_ARCH_STRCHRNUL
extern char * strchrnul(const char *,int);
#endif
+extern char * strnchrnul(const char *, size_t, int);
#ifndef __HAVE_ARCH_STRNCHR
extern char * strnchr(const char *, size_t, int);
#endif
diff --git a/lib/string.c b/lib/string.c
index 6016eb3ac73d..eee521ad1f40 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -429,6 +429,23 @@ char *strchrnul(const char *s, int c)
EXPORT_SYMBOL(strchrnul);
#endif
+/**
+ * strnchrnul - Find and return a character in a length limited string,
+ * or end of string
+ * @s: The string to be searched
+ * @count: The number of characters to be searched
+ * @c: The character to search for
+ *
+ * Returns pointer to the first occurrence of 'c' in s. If c is not found,
+ * then return a pointer to the last character of the string.
+ */
+char *strnchrnul(const char *s, size_t count, int c)
+{
+ while (count-- && *s && *s != (char)c)
+ s++;
+ return (char *)s;
+}
+
#ifndef __HAVE_ARCH_STRRCHR
/**
* strrchr - Find the last occurrence of a character in a string
--
2.17.1
