[U-Boot] [PATCH v3 18/19] lib: Implement strndup()

Thierry Reding
2019-03-21T18:01:17Z

include/linux/string.h | 1 +
lib/string.c | 23 +++++++++++++++++++++++
2 files changed, 24 insertions(+)

diff --git a/include/linux/string.h b/include/linux/string.h
index 36066207392e..5d63be4ce5b0 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -94,6 +94,7 @@ size_t strcspn(const char *s, const char *reject);
#ifndef __HAVE_ARCH_STRDUP
extern char * strdup(const char *);
#endif
+extern char * strndup(const char *, size_t);
#ifndef __HAVE_ARCH_STRSWAB
extern char * strswab(const char *);
#endif
diff --git a/lib/string.c b/lib/string.c
index af17c16f616d..9b779ddc3bbe 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -326,6 +326,29 @@ char * strdup(const char *s)
}
#endif

+char * strndup(const char *s, size_t n)
+{
+ size_t len;
+ char *new;
+
+ if (s == NULL)
+ return NULL;
+
+ len = strlen(s);
+
+ if (n < len)
+ len = n;
+
+ new = malloc(len + 1);
+ if (new == NULL)
+ return NULL;
+
+ strncpy(new, s, len);
+ new[len] = '\0';
+
+ return new;
+}
+
#ifndef __HAVE_ARCH_STRSPN
/**
* strspn - Calculate the length of the initial substring of @s which only
--
2.21.0