[hackers] [sbase] Fix mapping a class to a simple set and improve error-reporting || FRIGN

[git]

commit 7a644aea7d3c2cd3f44b8fa15c5ccdc91f111585
Author: FRIGN <d...@frign.de>
Date:   Mon Jan 12 00:03:48 2015 +0100

    Fix mapping a class to a simple set and improve error-reporting
    
    It's standard behaviour to map a whole class of matched objects
    to the last element of a given simple set2 instead of just passing
    it through.
    Also, error out more strictly when the user gives us bogus sets.

diff --git a/tr.c b/tr.c
index 828adba..d2bf7e0 100644
--- a/tr.c
+++ b/tr.c
@@ -110,7 +110,7 @@ nextbrack:
                                                return 0;
                                        }
                                }
-                               eprintf("Invalid character class\n");
+                               eprintf("Invalid character class.\n");
                        }
 
                        /* REPEAT  [_*n] (only allowed in set2) */
@@ -192,7 +192,9 @@ main(int argc, char *argv[])
        if (argc == 2)
                set2ranges = makeset(argv[1], &set2, &set2check);
        if (dflag == sflag && !set2ranges && !set2check)
-               eprintf("set2 must be non-empty\n");
+               eprintf("set2 must be non-empty.\n");
+       if (set2check && set2check != iswlower && set2check != iswupper)
+               eprintf("set2 can only be the 'lower' or 'upper' class.\n");
 read:
        if (!readrune("<stdin>", stdin, &r))
                return 0;
@@ -238,8 +240,12 @@ read:
                }
                if (set1check == iswupper && set2check == iswlower)
                        r = towlower((wint_t)r);
-               if (set1check == iswlower && set2check == iswupper)
+               else if (set1check == iswlower && set2check == iswupper)
                        r = towupper((wint_t)r);
+               else if (set2ranges > 0)
+                       r = set2[set2ranges - 1].end;
+               else
+                       eprintf("Misaligned character classes.\n");
        }
        if (dflag && cflag)
                goto read;