+<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
+<link rel="stylesheet" href="style.css" type="text/css"/>
+<script src="code.js" type="text/javascript"></script>
+
+<h1>glibc strverscmp</h1>
+
+<pre class="code">
+<span class="comment">/* Compare S1 and S2 as strings holding indices/version numbers,
+ returning less than, equal to or greater than zero if S1 is less than,
+ equal to or greater than S2 (for more info, see the texinfo doc).
+*/</span>
+
+int
+__strverscmp (const char *s1, const char *s2)
+{
+ const unsigned char *p1 = (const unsigned char *) s1;
+ const unsigned char *p2 = (const unsigned char *) s2;
+
+ /* Symbol(s) 0 [1-9] others
+ Transition (10) 0 (01) d (00) x */
+ static const uint8_t next_state[] =
+ {
+ /* state x d 0 */
+ /* S_N */ S_N, S_I, S_Z,
+ /* S_I */ S_N, S_I, S_I,
+ /* S_F */ S_N, S_F, S_F,
+ /* S_Z */ S_N, S_F, S_Z
+ };
+
+ static const int8_t result_type[] =
+ {
+ /* state x/x x/d x/0 d/x d/d d/0 0/x 0/d 0/0 */
+
+ /* S_N */ CMP, CMP, CMP, CMP, LEN, CMP, CMP, CMP, CMP,
+ /* S_I */ CMP, -1, -1, +1, LEN, LEN, +1, LEN, LEN,
+ /* S_F */ CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
+ /* S_Z */ CMP, +1, +1, -1, CMP, CMP, -1, CMP, CMP
+ };
+
+ if (p1 == p2)
+ return 0;
+
+ unsigned char c1 = *p1++;
+ unsigned char c2 = *p2++;
+ /* Hint: '0' is a digit too. */
+ int state = S_N + ((c1 == '0') + (__my_isdigit (c1) != 0));
+
+ int diff;
+ while ((diff = c1 - c2) == 0)
+ {
+ if (c1 == '\0')
+ return diff;
+
+ state = next_state[state];
+ c1 = *p1++;
+ c2 = *p2++;
+ state += (c1 == '0') + (__my_isdigit (c1) != 0);
+ }
+
+ state = result_type[state * 3 + (((c2 == '0') + (__my_isdigit (c2) != 0)))];
+
+ switch (state)
+ {
+ case CMP:
+ return diff;
+
+ case LEN:
+ while (__my_isdigit (*p1++))
+ if (!__my_isdigit (*p2++))
+ return 1;
+
+ return __my_isdigit (*p2) ? -1 : diff;
+
+ default:
+ return state;
+ }
+}
+</pre>