(size_trunc_len): support automatic maximum unit for specified size.

Fix typos.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>

lib/util.c

@@ -406,6 +406,7 @@ size_trunc_sep (uintmax_t size, gboolean use_si)
  *
  * Units: size units (filesystem sizes are 1K blocks)
  *    0=bytes, 1=Kbytes, 2=Mbytes, etc.
+ *    -1 means maximum possible unit for specified size
  */
 
 void
@@ -425,7 +426,7 @@ size_trunc_len (char *buffer, unsigned int len, uintmax_t size, int units, gbool
         10000000ULL,
         100000000ULL,
         1000000000ULL
-    /* maximmum value of uintmax_t (in case of 4 bytes) is
+    /* maximum value of uintmax_t (in case of 4 bytes) is
         4294967295
      */
 #if SIZEOF_UINTMAX_T == 8
@@ -440,7 +441,7 @@ size_trunc_len (char *buffer, unsigned int len, uintmax_t size, int units, gbool
         100000000000000000ULL,
         1000000000000000000ULL,
         10000000000000000000ULL
-    /* maximmum value of uintmax_t (in case of 8 bytes) is
+    /* maximum value of uintmax_t (in case of 8 bytes) is
         18447644073710439615
      */
 #endif
@@ -462,6 +463,16 @@ size_trunc_len (char *buffer, unsigned int len, uintmax_t size, int units, gbool
         len = 9;
 #endif
 
+    /* find maximum unit */
+    if (units < 0)
+    {
+        const unsigned int divider = use_si ? 1000 : 1024;
+        uintmax_t size_remain = size;
+
+        for (units = 0; size_remain >= divider; units++)
+            size_remain /= divider;
+    }
+
     /*
      * recalculate from 1024 base to 1000 base if units>0
      * We can't just multiply by 1024 - that might cause overflow