Bugfix: cbuf_cmp handled prefixes incorrectly.

The previous version returned 0 if the string to compare was either
equal to or a prefix of the target buffer. This change fixes it to
only return 0 when the string is actually equal. Otherwise, it follows
the shortlex ordering, for convenience.

2 files changed, 8 insertions, 1 deletions

diff --git a/util.c b/util.c
index e88ef95..643487b 100644
--- a/util.c
+++ b/util.c
@@ -93,7 +93,13 @@ const char *cbuf_get(struct cbuf *buf, size_t *len) {
 }
 
 int cbuf_cmp(cbuf *buf, const char *other) {
-  return strncmp(buf->data, other, buf->len);
+  size_t other_len = strlen(other);
+  if (buf->len < other_len)
+    return -1;
+  else if (buf->len == other_len)
+    return memcmp(buf->data, other, buf->len);
+  else
+    return +1;
 }
 
 // string lists
diff --git a/util.h b/util.h
index 70cd474..e1acc35 100644
--- a/util.h
+++ b/util.h
@@ -17,6 +17,7 @@ void cbuf_puts(cbuf *buf, const char *src);
 void cbuf_putc(cbuf *buf, int c);
 void cbuf_putf(cbuf *buf, const char *fmt, ...);
 const char *cbuf_get(struct cbuf *buf, size_t *len);
+/** Compares the contents of \p buf to the string in \p other, in shortlex order. */
 int cbuf_cmp(cbuf *buf, const char *other);
 
 // string lists