ascii.h

// Copyright (c) 2014 The Trident Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Author: Zuoyan Qin (qinzuoyan@gmail.com)

#ifndef _TRIDENT_ASCII_H_
#define _TRIDENT_ASCII_H_

#include <limits.h>
#include <stdint.h>

namespace trident {

struct Ascii
{
private:
    Ascii();
    ~Ascii();
private:
    enum CharTypeMask
    {
        kUpper = 1 << 0,
        kLower = 1 << 1,
        kDigit = 1 << 2,
        kHexDigit = 1 << 3,
        kBlank = 1 << 4,
        kSpace = 1 << 5,
        kControl = 1 << 6,
        kPunct = 1 << 7,
        kPrint = 1 << 8,
        kGraph = 1 << 9,
    };
public:
    static inline bool is_valid(char c)
    {
        return (c & 0x80) == 0;
    }

    static inline bool is_lower(char c)
    {
        return char_include_any_type_mask(c, kLower);
    }

    static inline bool is_upper(char c)
    {
        return char_include_any_type_mask(c, kUpper);
    }

    static inline bool is_alpha(char c)
    {
        return char_include_any_type_mask(c, kUpper | kLower);
    }

    static inline bool is_digit(char c)
    {
        return char_include_any_type_mask(c, kDigit);
    }

    static inline bool is_alpha_number(char c)
    {
        return char_include_any_type_mask(c, kUpper | kLower | kDigit);
    }

    static inline bool is_blank(char c)
    {
        return char_include_any_type_mask(c, kBlank);
    }

    static inline bool is_space(char c)
    {
        return char_include_any_type_mask(c, kSpace);
    }

    static inline bool is_control(char c)
    {
        return char_include_any_type_mask(c, kControl);
    }

    static inline bool is_punct(char c)
    {
        return char_include_any_type_mask(c, kPunct);
    }

    static inline bool is_hex_digit(char c)
    {
        return char_include_any_type_mask(c, kHexDigit);
    }

    static inline bool is_graph(char c)
    {
        return char_include_any_type_mask(c, kGraph);
    }

    static inline bool is_print(char c)
    {
        return char_include_any_type_mask(c, kPrint);
    }

    static inline char to_ascii(char c)
    {
        return c & 0x7F;
    }

    static inline char to_lower(char c)
    {
        return is_upper(c) ? c + ('a' - 'A') : c;
    }

    static inline char to_upper(char c)
    {
        return is_lower(c) ? c - ('a' - 'A') : c;
    }

private:
    static inline int get_char_type_mask(char c)
    {
        //////////// Table Generator Begin /////////////
        // #include <ctype.h>
        // #include <stdio.h>
        // int main()
        // {
        //     for (int i = 0; i < 128; ++i)
        //     {
        //         printf("            /* 0x%02x(%c) */ ", i, isgraph(i) ? i : ' ');
        //         if (isblank(i)) printf("kBlank | ");
        //         if (isspace(i)) printf("kSpace | ");
        //         if (isupper(i)) printf("kUpper | ");
        //         if (islower(i)) printf("kLower | ");
        //         if (isdigit(i)) printf("kDigit | ");
        //         if (isxdigit(i)) printf("kHexDigit | ");
        //         if (ispunct(i)) printf("kPunct | ");
        //         if (iscntrl(i)) printf("kControl | ");
        //         if (isgraph(i)) printf("kGraph | ");
        //         if (isprint(i)) printf("kPrint | ");
        //         printf("0,\n");
        //     }
        // }
        //////////// Table Generator End /////////////
        // Run with this command:
        // $ LC_ALL=C ./a.out
        //////////////////////////////////////////////
        static const uint16_t table[UCHAR_MAX + 1] =
        {
            /* 0x00( ) */ kControl | 0,
            /* 0x01( ) */ kControl | 0,
            /* 0x02( ) */ kControl | 0,
            /* 0x03( ) */ kControl | 0,
            /* 0x04( ) */ kControl | 0,
            /* 0x05( ) */ kControl | 0,
            /* 0x06( ) */ kControl | 0,
            /* 0x07( ) */ kControl | 0,
            /* 0x08( ) */ kControl | 0,
            /* 0x09( ) */ kBlank | kSpace | kControl | 0,
            /* 0x0a( ) */ kSpace | kControl | 0,
            /* 0x0b( ) */ kSpace | kControl | 0,
            /* 0x0c( ) */ kSpace | kControl | 0,
            /* 0x0d( ) */ kSpace | kControl | 0,
            /* 0x0e( ) */ kControl | 0,
            /* 0x0f( ) */ kControl | 0,
            /* 0x10( ) */ kControl | 0,
            /* 0x11( ) */ kControl | 0,
            /* 0x12( ) */ kControl | 0,
            /* 0x13( ) */ kControl | 0,
            /* 0x14( ) */ kControl | 0,
            /* 0x15( ) */ kControl | 0,
            /* 0x16( ) */ kControl | 0,
            /* 0x17( ) */ kControl | 0,
            /* 0x18( ) */ kControl | 0,
            /* 0x19( ) */ kControl | 0,
            /* 0x1a( ) */ kControl | 0,
            /* 0x1b( ) */ kControl | 0,
            /* 0x1c( ) */ kControl | 0,
            /* 0x1d( ) */ kControl | 0,
            /* 0x1e( ) */ kControl | 0,
            /* 0x1f( ) */ kControl | 0,
            /* 0x20( ) */ kBlank | kSpace | kPrint | 0,
            /* 0x21(!) */ kPunct | kGraph | kPrint | 0,
            /* 0x22(") */ kPunct | kGraph | kPrint | 0,
            /* 0x23(#) */ kPunct | kGraph | kPrint | 0,
            /* 0x24($) */ kPunct | kGraph | kPrint | 0,
            /* 0x25(%) */ kPunct | kGraph | kPrint | 0,
            /* 0x26(&) */ kPunct | kGraph | kPrint | 0,
            /* 0x27(') */ kPunct | kGraph | kPrint | 0,
            /* 0x28(() */ kPunct | kGraph | kPrint | 0,
            /* 0x29()) */ kPunct | kGraph | kPrint | 0,
            /* 0x2a(*) */ kPunct | kGraph | kPrint | 0,
            /* 0x2b(+) */ kPunct | kGraph | kPrint | 0,
            /* 0x2c(,) */ kPunct | kGraph | kPrint | 0,
            /* 0x2d(-) */ kPunct | kGraph | kPrint | 0,
            /* 0x2e(.) */ kPunct | kGraph | kPrint | 0,
            /* 0x2f(/) */ kPunct | kGraph | kPrint | 0,
            /* 0x30(0) */ kDigit | kHexDigit | kGraph | kPrint | 0,
            /* 0x31(1) */ kDigit | kHexDigit | kGraph | kPrint | 0,
            /* 0x32(2) */ kDigit | kHexDigit | kGraph | kPrint | 0,
            /* 0x33(3) */ kDigit | kHexDigit | kGraph | kPrint | 0,
            /* 0x34(4) */ kDigit | kHexDigit | kGraph | kPrint | 0,
            /* 0x35(5) */ kDigit | kHexDigit | kGraph | kPrint | 0,
            /* 0x36(6) */ kDigit | kHexDigit | kGraph | kPrint | 0,
            /* 0x37(7) */ kDigit | kHexDigit | kGraph | kPrint | 0,
            /* 0x38(8) */ kDigit | kHexDigit | kGraph | kPrint | 0,
            /* 0x39(9) */ kDigit | kHexDigit | kGraph | kPrint | 0,
            /* 0x3a(:) */ kPunct | kGraph | kPrint | 0,
            /* 0x3b(;) */ kPunct | kGraph | kPrint | 0,
            /* 0x3c(<) */ kPunct | kGraph | kPrint | 0,
            /* 0x3d(=) */ kPunct | kGraph | kPrint | 0,
            /* 0x3e(>) */ kPunct | kGraph | kPrint | 0,
            /* 0x3f(?) */ kPunct | kGraph | kPrint | 0,
            /* 0x40(@) */ kPunct | kGraph | kPrint | 0,
            /* 0x41(A) */ kUpper | kHexDigit | kGraph | kPrint | 0,
            /* 0x42(B) */ kUpper | kHexDigit | kGraph | kPrint | 0,
            /* 0x43(C) */ kUpper | kHexDigit | kGraph | kPrint | 0,
            /* 0x44(D) */ kUpper | kHexDigit | kGraph | kPrint | 0,
            /* 0x45(E) */ kUpper | kHexDigit | kGraph | kPrint | 0,
            /* 0x46(F) */ kUpper | kHexDigit | kGraph | kPrint | 0,
            /* 0x47(G) */ kUpper | kGraph | kPrint | 0,
            /* 0x48(H) */ kUpper | kGraph | kPrint | 0,
            /* 0x49(I) */ kUpper | kGraph | kPrint | 0,
            /* 0x4a(J) */ kUpper | kGraph | kPrint | 0,
            /* 0x4b(K) */ kUpper | kGraph | kPrint | 0,
            /* 0x4c(L) */ kUpper | kGraph | kPrint | 0,
            /* 0x4d(M) */ kUpper | kGraph | kPrint | 0,
            /* 0x4e(N) */ kUpper | kGraph | kPrint | 0,
            /* 0x4f(O) */ kUpper | kGraph | kPrint | 0,
            /* 0x50(P) */ kUpper | kGraph | kPrint | 0,
            /* 0x51(Q) */ kUpper | kGraph | kPrint | 0,
            /* 0x52(R) */ kUpper | kGraph | kPrint | 0,
            /* 0x53(S) */ kUpper | kGraph | kPrint | 0,
            /* 0x54(T) */ kUpper | kGraph | kPrint | 0,
            /* 0x55(U) */ kUpper | kGraph | kPrint | 0,
            /* 0x56(V) */ kUpper | kGraph | kPrint | 0,
            /* 0x57(W) */ kUpper | kGraph | kPrint | 0,
            /* 0x58(X) */ kUpper | kGraph | kPrint | 0,
            /* 0x59(Y) */ kUpper | kGraph | kPrint | 0,
            /* 0x5a(Z) */ kUpper | kGraph | kPrint | 0,
            /* 0x5b([) */ kPunct | kGraph | kPrint | 0,
            /* 0x5c(\) */ kPunct | kGraph | kPrint | 0,
            /* 0x5d(]) */ kPunct | kGraph | kPrint | 0,
            /* 0x5e(^) */ kPunct | kGraph | kPrint | 0,
            /* 0x5f(_) */ kPunct | kGraph | kPrint | 0,
            /* 0x60(`) */ kPunct | kGraph | kPrint | 0,
            /* 0x61(a) */ kLower | kHexDigit | kGraph | kPrint | 0,
            /* 0x62(b) */ kLower | kHexDigit | kGraph | kPrint | 0,
            /* 0x63(c) */ kLower | kHexDigit | kGraph | kPrint | 0,
            /* 0x64(d) */ kLower | kHexDigit | kGraph | kPrint | 0,
            /* 0x65(e) */ kLower | kHexDigit | kGraph | kPrint | 0,
            /* 0x66(f) */ kLower | kHexDigit | kGraph | kPrint | 0,
            /* 0x67(g) */ kLower | kGraph | kPrint | 0,
            /* 0x68(h) */ kLower | kGraph | kPrint | 0,
            /* 0x69(i) */ kLower | kGraph | kPrint | 0,
            /* 0x6a(j) */ kLower | kGraph | kPrint | 0,
            /* 0x6b(k) */ kLower | kGraph | kPrint | 0,
            /* 0x6c(l) */ kLower | kGraph | kPrint | 0,
            /* 0x6d(m) */ kLower | kGraph | kPrint | 0,
            /* 0x6e(n) */ kLower | kGraph | kPrint | 0,
            /* 0x6f(o) */ kLower | kGraph | kPrint | 0,
            /* 0x70(p) */ kLower | kGraph | kPrint | 0,
            /* 0x71(q) */ kLower | kGraph | kPrint | 0,
            /* 0x72(r) */ kLower | kGraph | kPrint | 0,
            /* 0x73(s) */ kLower | kGraph | kPrint | 0,
            /* 0x74(t) */ kLower | kGraph | kPrint | 0,
            /* 0x75(u) */ kLower | kGraph | kPrint | 0,
            /* 0x76(v) */ kLower | kGraph | kPrint | 0,
            /* 0x77(w) */ kLower | kGraph | kPrint | 0,
            /* 0x78(x) */ kLower | kGraph | kPrint | 0,
            /* 0x79(y) */ kLower | kGraph | kPrint | 0,
            /* 0x7a(z) */ kLower | kGraph | kPrint | 0,
            /* 0x7b({) */ kPunct | kGraph | kPrint | 0,
            /* 0x7c(|) */ kPunct | kGraph | kPrint | 0,
            /* 0x7d(}) */ kPunct | kGraph | kPrint | 0,
            /* 0x7e(~) */ kPunct | kGraph | kPrint | 0,
            /* 0x7f( ) */ kControl | 0,
            // the followings are all 0
        };
        return table[static_cast<unsigned char>(c)];
    }

    static bool char_include_any_type_mask(char c, int mask)
    {
        return (get_char_type_mask(c) & mask) != 0;
    }

    static bool char_include_all_type_mask(char c, int mask)
    {
        return (get_char_type_mask(c) & mask) == mask;
    }
};

} // namespace trident

#endif // _TRIDENT_ASCII_H_