From: Masatake YAMATO <yamato@redhat.com>
Date: Tue, 13 Jun 2017 08:26:42 +0000 (+0900)
Subject: Introduce xstrndup function
X-Git-Tag: v4.18~66
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=d10d64820f3d61331022c3f44d2f035b65ef86ec;p=strace

Introduce xstrndup function

* configure.ac (AC_CHECK_FUNCS): Add strndup.
* defs.h (xstrndup): New prototype.
* xmalloc.c (xstrndup): New function.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
---

diff --git a/configure.ac b/configure.ac
index b4cf4cb2..d510f41e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -283,6 +283,7 @@ AC_CHECK_FUNCS(m4_normalize([
 	signalfd
 	stpcpy
 	strerror
+	strndup
 	strsignal
 	sync_file_range
 	utimensat
diff --git a/defs.h b/defs.h
index 8a28e896..5e054577 100644
--- a/defs.h
+++ b/defs.h
@@ -401,6 +401,7 @@ void *xcalloc(size_t nmemb, size_t size)
 void *xreallocarray(void *ptr, size_t nmemb, size_t size)
 	ATTRIBUTE_ALLOC_SIZE((2, 3));
 char *xstrdup(const char *str) ATTRIBUTE_MALLOC;
+char *xstrndup(const char *str, size_t n) ATTRIBUTE_MALLOC;
 
 extern int read_int_from_file(const char *, int *);
 
diff --git a/xmalloc.c b/xmalloc.c
index a0176200..3ef48567 100644
--- a/xmalloc.c
+++ b/xmalloc.c
@@ -85,3 +85,24 @@ char *xstrdup(const char *str)
 
 	return p;
 }
+
+char *xstrndup(const char *str, size_t n)
+{
+	char *p;
+
+#ifdef HAVE_STRNDUP
+	p = strndup(str, n);
+#else
+	p = xmalloc(n + 1);
+#endif
+
+	if (!p)
+		die_out_of_memory();
+
+#ifndef HAVE_STRNDUP
+	strncpy(p, str, n);
+	p[n] = '\0';
+#endif
+
+	return p;
+}