--- src/fsearch_string_utils.c.orig	2022-08-17 17:50:25 UTC
+++ src/fsearch_string_utils.c
@@ -164,3 +164,91 @@ fsearch_string_starts_with_interval(char *str, char **
     *end_ptr = str;
     return false;
 }
+
+/* Compare strings while treating digits characters numerically.
+   Copyright (C) 1997-2022 Free Software Foundation, Inc.
+   Contributed by Jean-François Bignolles <bignolle@ecoledoc.ibp.fr>,
+   1997. */
+
+#include <stdint.h>
+
+/* states: S_N: normal, S_I: comparing integral part, S_F: comparing
+           fractional parts, S_Z: idem but with leading Zeroes only */
+#define  S_N    0x0
+#define  S_I    0x3
+#define  S_F    0x6
+#define  S_Z    0x9
+
+/* result_type: CMP: return diff; LEN: compare using len_diff/diff */
+#define  CMP    2
+#define  LEN    3
+
+/* 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. */
+
+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 uint_least8_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 int_least8_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') + (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') + (isdigit (c1) != 0);
+    }
+
+  state = result_type[state * 3 + (((c2 == '0') + (isdigit (c2) != 0)))];
+
+  switch (state)
+  {
+    case CMP:
+      return diff;
+
+    case LEN:
+      while (isdigit (*p1++))
+	if (!isdigit (*p2++))
+	  return 1;
+
+      return isdigit (*p2) ? -1 : diff;
+
+    default:
+      return state;
+  }
+}
