util: add string-util.[ch]

This is to give a home to strtok_len. It's a bit silly to add a header
for one routine, but it needs to be shared between several compilation
units (or at least that's the most natural design).

1 files changed, 22 insertions, 0 deletions

diff --git a/util/string-util.h b/util/string-util.h
new file mode 100644
index 00000000..ac7676c8
--- /dev/null
+++ b/util/string-util.h
@@ -0,0 +1,22 @@
+#ifndef _STRING_UTIL_H
+#define _STRING_UTIL_H
+
+#include <string.h>
+
+/* like strtok(3), but without state, and doesn't modify s.  Return
+ * value is indicated by pointer and length, not null terminator.
+ *
+ * Usage pattern:
+ *
+ * const char *tok = input;
+ * const char *delim = " \t";
+ * size_t tok_len = 0;
+ *
+ * while ((tok = strtok_len (tok + tok_len, delim, &tok_len)) != NULL) {
+ *     // do stuff with string tok of length tok_len
+ * }
+ */
+
+char *strtok_len (char *s, const char *delim, size_t *len);
+
+#endif