New function(s): strnmatch() and strmatch()

These two functions look for a string in a (terminate) list of strings
and returns the index to that string, or -1 if not found or error.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

src/Makefile.am

@@ -14,6 +14,7 @@ libite_la_SOURCES     = chomp.c		copyfile.c			\
 			reallocarray.c	rsync.c				\
 			strlcpy.c 	strlcat.c 	strtonum.c	\
 			strdupa.h	strndupa.h	strnlen.h	\
+			strmatch.c					\
 			tempfile.c	which.c				\
 			lite.h		strlite.h			\
 			queue.h		tree.h

src/strlite.h

@@ -49,6 +49,9 @@
 	})
 #endif
 
+int     strnmatch  (const char *str, const char **list, size_t num);
+int     strmatch   (const char *str, const char **list);
+
 #ifndef strlcpy
 size_t  strlcpy    (char *dst, const char *src, size_t siz);
 #endif

src/strmatch.c

@@ -0,0 +1,89 @@
+/* Simple string matcher function, finds partial matches.
+ *
+ * Copyright (c) 2009-2018  Joachim Nilsson <troglobit@gmail.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <errno.h>
+#include <string.h>
+
+
+/**
+ * strnmatch - Finds matching strings from a finite list
+ * @str: String to look for
+ * @list: List of strings to search.
+ * @num: Number of entries in @list.
+ *
+ * This function searches the @list of strings for @str.  If a (partial) match
+ * is found it returns the index in the @list.
+ *
+ * Very similar in function to strmatch(), but works for sets of strings that
+ * are not %NULL terminated.
+ *
+ * Returns:
+ * -1 on error, otherwise the index to the matching string.
+ */
+int strnmatch(const char *str, const char **list, size_t num)
+{
+	size_t i;
+
+	if (!str || !list) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	for (i = 0; i < num; i++) {
+		if (!strncasecmp (str, list[i], strlen (str)))
+			return i;
+	}
+
+	errno = ENOENT;
+	return -1;
+}
+
+/**
+ * strmatch - Finds matching strings from a list
+ * @str: String to look for
+ * @list: %NULL terminated list of strings to search.
+ *
+ * This function searches the @list of strings for @str.  If a (partial) match
+ * is found it returns the index in the @list.
+ *
+ * Please note, the @list MUST be terminated by a %NULL element.  If that is
+ * not possible for you, we recommend using strnmatch() instead.
+ *
+ * Returns:
+ * -1 on error, otherwise the index to the matching string.
+ */
+int strmatch(const char *str, const char **list)
+{
+	size_t i;
+
+	if (!list) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	for (i = 0; list[i]; i++)
+		;
+
+	return strnmatch(str, list, i);
+}
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */