libc: Add ctype.h

libs/libc/include/ctype.h

@@ -0,0 +1,58 @@
+#ifndef _CTYPE_H
+#define _CTYPE_H
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+    /* Is this character alphanumeric? */
+    int isalnum(int c);
+
+    /* Is this character a letter? */
+    int isalpha(int c);
+
+    /* Is this character part of ASCII? */
+    int isascii(int c);
+
+    /* Is this character a blank character (space or tab)? */
+    int isblank(int c);
+
+    /* Is this character a control character? */
+    int iscntrl(int c);
+
+    /* Is this character a digit? */
+    int isdigit(int c);
+
+    /* Is this character any printable character except space? */
+    int isgraph(int c);
+
+    /* Is this character a lowercase letter? */
+    int islower(int c);
+
+    /* Is this character any printable character (including space)? */
+    int isprint(int c);
+
+    /* Is this character any printable character which is not a space or an alphanumeric character? */
+    int ispunct(int c);
+
+    /* Is this character any space character (space, form feed, newline, carriage return, tab, vertical tab)? */
+    int isspace(int c);
+
+    /* Is this character an uppercase letter? */
+    int isupper(int c);
+
+    /* Is this character a hexadecimal digit (0-9, a-f, A-F)? */
+    int isxdigit(int c);
+
+    /* Returns the lowercase form of the specified character. */
+    int tolower(int c);
+
+    /* Returns the uppercase form of the specified character. */
+    int toupper(int c);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

libs/libc/src/ctype.cpp

@@ -0,0 +1,81 @@
+#include <ctype.h>
+
+extern "C"
+{
+    int isalnum(int c)
+    {
+        return isalpha(c) || isdigit(c);
+    }
+
+    int isalpha(int c)
+    {
+        return islower(c) || isupper(c);
+    }
+
+    int isascii(int c)
+    {
+        return !(c & ~0x7f);
+    }
+
+    int isblank(int c)
+    {
+        return c == ' ' || c == '\t';
+    }
+
+    int iscntrl(int c)
+    {
+        return (unsigned int)c < 0x20 || c == 0x7f;
+    }
+
+    int isdigit(int c)
+    {
+        return c >= '0' && c < ':';
+    }
+
+    int isgraph(int c)
+    {
+        return (unsigned int)c - 0x21 < 0x5e;
+    }
+
+    int islower(int c)
+    {
+        return c >= 'a' && c < '{';
+    }
+
+    int isprint(int c)
+    {
+        return (unsigned int)c - 0x20 < 0x5f;
+    }
+
+    int ispunct(int c)
+    {
+        return isgraph(c) && !isalnum(c);
+    }
+
+    int isspace(int c)
+    {
+        return c == ' ' || (unsigned int)c - '\t' < 5;
+    }
+
+    int isupper(int c)
+    {
+        return c >= 'A' && c < '[';
+    }
+
+    int isxdigit(int c)
+    {
+        return isdigit(c) || ((unsigned int)c | 32) - 'a' < 6;
+    }
+
+    int tolower(int c)
+    {
+        if (isupper(c)) return c | 32;
+        return c;
+    }
+
+    int toupper(int c)
+    {
+        if (islower(c)) return c & 0x5f;
+        return c;
+    }
+}