ctype: restore character classification for non-ASCII platforms

With commit 4272a0b0fc49a1ac0ceab5c4a365c9f6ab8bf8e2 curl-speficic
character classification macros and functions were introduced in
curl_ctype.[ch] to avoid dependencies on the locale. This broke curl on
non-ASCII, e.g. EBCDIC platforms. This change restores the previous set
of character classification macros when CURL_DOES_CONVERSIONS is
defined.

Closes #2494

1 files changed, 30 insertions, 0 deletions

diff --git a/lib/curl_ctype.h b/lib/curl_ctype.h
index da3bd95a6..1ffecb99a 100644
--- a/lib/curl_ctype.h
+++ b/lib/curl_ctype.h
@@ -22,6 +22,33 @@
  *
  ***************************************************************************/
 
+#include "curl_setup.h"
+
+#ifdef CURL_DOES_CONVERSIONS
+
+/*
+ * Uppercase macro versions of ANSI/ISO is*() functions/macros which
+ * avoid negative number inputs with argument byte codes > 127.
+ *
+ * For non-ASCII platforms the C library character classification routines
+ * are used despite being locale-dependent, because this is better than
+ * not to work at all.
+ */
+#include <ctype.h>
+
+#define ISSPACE(x)  (isspace((int)  ((unsigned char)x)))
+#define ISDIGIT(x)  (isdigit((int)  ((unsigned char)x)))
+#define ISALNUM(x)  (isalnum((int)  ((unsigned char)x)))
+#define ISXDIGIT(x) (isxdigit((int) ((unsigned char)x)))
+#define ISGRAPH(x)  (isgraph((int)  ((unsigned char)x)))
+#define ISALPHA(x)  (isalpha((int)  ((unsigned char)x)))
+#define ISPRINT(x)  (isprint((int)  ((unsigned char)x)))
+#define ISUPPER(x)  (isupper((int)  ((unsigned char)x)))
+#define ISLOWER(x)  (islower((int)  ((unsigned char)x)))
+#define ISASCII(x)  (isascii((int)  ((unsigned char)x)))
+
+#else
+
 int Curl_isspace(int c);
 int Curl_isdigit(int c);
 int Curl_isalnum(int c);
@@ -42,6 +69,9 @@ int Curl_islower(int c);
 #define ISUPPER(x)  (Curl_isupper((int)  ((unsigned char)x)))
 #define ISLOWER(x)  (Curl_islower((int)  ((unsigned char)x)))
 #define ISASCII(x)  (((x) >= 0) && ((x) <= 0x80))
+
+#endif
+
 #define ISBLANK(x)  (int)((((unsigned char)x) == ' ') ||        \
                           (((unsigned char)x) == '\t'))