win32: actype: code shrink

Unify actype/actail into a single function, and make actype
a wrapper macro which invokes actail(str, NULL) (to avoid calling
a function actype which then trampolines to actail with NULL).

This concludes the integration of actype/isactype.

Overall:
- Unified/standard-ish char-class handling in fnmatch/regcomp/tr.
- Saved about 1400 bytes at the binary as x64.
- regcomp.c is negligibly faster (actype/isactype are O(1)).
- tr.c now also supports [:graph:] and [:print:], and not slower.

fnmatch.c (tested using scripts/patbench.sh):

Before actype was integrated, alnum was fastest and xdigit slowest
due to their order in the names strings list and in the switch/case:

[35]   1305 ms  OK      (M:12-45)  '*[0-9A-Za-z]*[0-9A-Za-z]'
[36]   1928 ms  OK      (M:12-45)  '*[[:alnum:]]*[[:alnum:]]'

[38]   1446 ms  OK      (M:12-45)  '*[a-bc-de-z]*[a-bc-de-z]'
[39]   3192 ms  OK      (M:12-45)  '*[[:lower:]]*[[:lower:]]'

[40]   1586 ms  OK      (M:---4-)  '*[0-9A-Fa-ef]*[0-9A-Fa-ef]'
[41]   4601 ms  OK      (M:---4-)  '*[[:xdigit:]]*[[:xdigit:]]'

Now all classes are similar relative to an equivalent range,
and just barely slower than "alnum" before actype was added
(still slower than range due to additional temp name buffer):

[35]   1402 ms  OK      (M:12-45)  '*[0-9A-Za-z]*[0-9A-Za-z]'
[36]   1962 ms  OK      (M:12-45)  '*[[:alnum:]]*[[:alnum:]]'

[38]   1453 ms  OK      (M:12-45)  '*[a-bc-de-z]*[a-bc-de-z]'
[39]   1965 ms  OK      (M:12-45)  '*[[:lower:]]*[[:lower:]]'

[40]   1683 ms  OK      (M:---4-)  '*[0-9A-Fa-ef]*[0-9A-Fa-ef]'
[41]   2117 ms  OK      (M:---4-)  '*[[:xdigit:]]*[[:xdigit:]]'

2 files changed, 13 insertions, 18 deletions

diff --git a/win32/actype.c b/win32/actype.c
index 4d0cf91a3..967de4644 100644
--- a/win32/actype.c
+++ b/win32/actype.c
@@ -31,10 +31,8 @@ along with this program; if not, see https://www.gnu.org/licenses/ .
 #endif
 
 #if ACTYPE_OPTIMIZE_FOR_SIZE
-  #include <string.h>  /* strcmp */
   char *is_prefixed_with(const char*, const char*);  /* libbb */
   #define IS_PREFIXED_WITH_CLASS is_prefixed_with
-  #define IS_CLASS(s, c)         (!strcmp((s), (c)))
 #else
   /* c[0]-c[4] are not 0, so we can skip these 0-tests, and do it inline.
    * in x64 this adds ~ 40 bytes, and actype/actail are almost x2 faster.
@@ -44,9 +42,6 @@ along with this program; if not, see https://www.gnu.org/licenses/ .
          ? c[5] ? /* xdigit */ s[5] == 't' ? s+6 : 0 \
                 : s+5 \
          : 0)
-
-  /* modifies s */
-  #define IS_CLASS(s, c) ((s = IS_PREFIXED_WITH_CLASS(s, c)) && !*s)
 #endif
 
 
@@ -107,27 +102,23 @@ const _isactype_t _actype_fns[] = {
         "alnum\0alpha\0blank\0cntrl\0digit\0graph\0" \
         "lower\0print\0punct\0space\0upper\0xdigit"
 
-actype_t actype(const char *s)
-{
-        int i = POTENTIAL_CLASS_IDX(s);
-        const char *c = CHAR_CLASSES + i * 6;
-
-        if (!IS_CLASS(s, c))
-                return 0;
-        return ACTYPE_FROM_IDX(i);
-}
-
 actype_t actail(const char *s, int *len)
 {
         int i = POTENTIAL_CLASS_IDX(s);
         const char *c = CHAR_CLASSES + i * 6;
 
         s = IS_PREFIXED_WITH_CLASS(s, c);
-
-        if (!s || *s++ != ':' || *s != ']')
+        if (!s)
                 return 0;
 
-        *len = 7 + (i == 11);  /* xdigit is 6, others are 5 */
+        /* done: s is just past the matched name, verify tail based on len */
+        if (len) {
+                if (*s++ != ':' || *s != ']')
+                        return 0;
+                *len = 7 + (i == 11);  /* xdigit is 6, others are 5 */
+        } else if (*s) {
+                return 0;
+        }
         return ACTYPE_FROM_IDX(i);
 }
 
diff --git a/win32/actype.h b/win32/actype.h
index d0a2da39f..4e906a7f1 100644
--- a/win32/actype.h
+++ b/win32/actype.h
@@ -46,6 +46,9 @@ typedef int (*_isactype_t)(int);  /* isalpha et-al prototype */
 extern actype_t actype(const char *name);
 extern int isactype(int c, actype_t t);
 
+/* actype above is the official prototype, but in practice we invoke actail */
+#define actype(name) (actail((name), NULL))
+
 
 /* extensions */
 
@@ -58,6 +61,7 @@ extern int isactype(int c, actype_t t);
  *   set *len=strlen("NAME:]") and return non-0 actype("NAME").
  * else return 0.
  * useful in typical char-class parsing scenarios.
+ * if len is NULL: identical to actype.
  */
 extern actype_t actail(const char *str, int *len);