学步园

#include <stdio.h>
#include <string>
#include <stdlib.h>

char *url_encode( const char *src , char * dest) {
    char * tmp;
    int n = strlen(src) + 1;

    tmp = dest;//0 = g_new0(char, n * 3);

    for (; *src != '/0' && n >= 0; src++, dest++, n--)
    {
        if ( strchr(":/?&=%+", *src) )
        {
            sprintf( dest, "%%%02X", (int) *src & 0xFF );
            dest += 2;
        } else if ( isalnum(*src) || strchr("./-_", *src) )
            *dest = *src;
        else if ( *src == ' ' )
            *dest = '+';
        else {
            sprintf( dest, "%%%02X", (int) *src & 0xFF );
            dest += 2;
        }
    }

    *dest = '/0';
    return tmp;
}

static int fromhex ( char digit )
{
    char d = toupper(digit);
    if (!isxdigit(digit)) return 0;
    if (isdigit(d))
    {
        return d - '0';
    }
    else
    {
        return (int) ( d - 'A' ) + 10;
    }
}

char * url_decode( const char *src , char * dest) {
    char * tmp;
    int n;

    n = strlen(src) + 1;
    tmp = dest;

    for (; *src != '/0' && n >= 0; ++dest, ++src, --n )
        if ( *src == '%' && n > 2 )  {
            *dest  = fromhex( *(++src) ) * 0x10;
            *dest += fromhex( *(++src) );
            n -= 2;
        } else if ( *src == '+' )
            *dest = ' ';
        else
            *dest = *src;

    *dest = '/0';
    return tmp;
}

int main()
{
    char * src = "Hello, World! 逍遥大海";
    int size = strlen(src);
    char * encode = new char[size * 3 + 1];
    printf("原始内容：%s/n", src);
    url_encode(src, encode);
    printf("编码内容：%s/n", encode);
    char * decode = new char[strlen(encode) + 1];
    url_decode(encode, decode);
    printf("解码内容：%s/n", decode);
    return 0;
}