lib: [strutils] general purpose string handling functions

This patch replaces a few functions used throughout the source:
* Renames getnum (from schedutils) to strtol_or_err
* Moves strtosize (from lib/strtosize.c)
* Moves xstrncpy (from include/xstrncpy.h)
* Adds strnlen, strnchr and strndup if not available (remove it from libmount utils)

A few Makefile.am files were modified to compile accordingly along with trivial renaming
in schedutils source code.

Signed-off-by: Davidlohr Bueso <dave@gnu.org>

1 files changed, 26 insertions, 0 deletions

diff --git a/include/strutils.h b/include/strutils.h
new file mode 100644
index 000000000..e24496d3c
--- /dev/null
+++ b/include/strutils.h
@@ -0,0 +1,26 @@
+#ifndef UTIL_LINUX_STRUTILS
+#define UTIL_LINUX_STRUTILS
+
+#include <inttypes.h>
+#include <string.h>
+
+extern int strtosize(const char *str, uintmax_t *res);
+extern long strtol_or_err(const char *str, const char *errmesg);
+
+#ifndef HAVE_STRNLEN
+extern size_t strnlen(const char *s, size_t maxlen);
+#endif
+#ifndef HAVE_STRNDUP
+extern char *strndup(const char *s, size_t n);
+#endif
+#ifndef HAVE_STRNCHR
+extern char *strnchr(const char *s, size_t maxlen, int c);
+#endif
+
+/* caller guarantees n > 0 */
+static inline void xstrncpy(char *dest, const char *src, size_t n)
+{
+	strncpy(dest, src, n-1);
+	dest[n-1] = 0;
+}
+#endif