myvtm/Module/mod_chromium/BufferOperation.h

#ifndef CBufferOperation_h
#define CBufferOperation_h

#include "SimpleString.h"
#include "AutoArray.h"
#include "Blob.h"

namespace Chromium{

#define IOBUF_T_I8	    0
#define IOBUF_T_I4	    1
#define IOBUF_T_I2	    2
#define IOBUF_T_I1	    3
#define IOBUF_T_STR	    4
#define IOBUF_T_BUF	    5
#define IOBUF_T_WSTR    6 /* wchar_t */
#define IOBUF_T_7BIT	7

/////////////////// Read Buf Start ///////////////////////
static void buffer_read_buf(const char *iobuf, char *buf, int n, int* rpos)
{
//	assert(content_size(iobuf) >= n);
	memcpy(buf, iobuf + *rpos, n);
	*rpos += n;
}

static void buffer_read_7bit_int(const char *iobuf, int *v, int* rpos)
{
	int count = 0;
	int shift = 0;
	unsigned char b;
	do {
		if (shift == 5*7) // corrupted stream
			assert(0);
		b = iobuf[*rpos];
		*rpos += 1;
		count |= (b & 0x7F) << shift;
		shift += 7;
	} while (b & 0x80);		// most left bit is flag
	*v = count;
}

static void buffer_read(const char *iobuf, int t, void *v, int *n, int* rpos){
	int len = 0;
	switch (t)
	{
	case IOBUF_T_I8:
		len += 8;
		buffer_read_buf(iobuf, (char*)v, len, rpos);
		break;
	case IOBUF_T_I4:
		len += 4;
		buffer_read_buf(iobuf, (char*)v, len, rpos);
		break;
	case IOBUF_T_I2:
		len += 2;
		buffer_read_buf(iobuf, (char*)v, len, rpos);
		break;
	case IOBUF_T_I1:
		len += 1;
		buffer_read_buf(iobuf, (char*)v, len, rpos);
		break;
	case IOBUF_T_STR:
		if (v) {
			int old_rpos = *rpos;
			buffer_read_7bit_int(iobuf, &len, rpos);
			if (!n || len < *n) {
				buffer_read_buf(iobuf, (char *)v, len, rpos);
				*((char*)v + len) = 0;
				if (n)
					*n = len;
			} else {
				*rpos = old_rpos;
				*n = len;
			}
		} else {
			if (n) {
				int old_rpos = *rpos;
				buffer_read_7bit_int(iobuf, &len, rpos);
				*rpos = old_rpos;
				*n = len;
			} else {
				assert(0);
			}
		}
		break;
	case IOBUF_T_WSTR:
		if (v) {
			int old_rpos = *rpos;
			buffer_read_7bit_int(iobuf, &len, rpos);
			if (!n || len < *n) {
				buffer_read_buf(iobuf, (char*)v, len, rpos); /* wchar_t */
				*((char*)v + len) = 0; // wchar termination char is 2 byte
				*((char*)v + len+1) = 0;
				if (n)
					*n = len;
			} else {
				*rpos = old_rpos;
				*n = len;
			}
		} else {
			if (n) {
				int old_rpos = *rpos;
				buffer_read_7bit_int(iobuf, &len, rpos);
				*rpos = old_rpos;
				*n = len;
			} else {
				assert(0);
			}
		}
		break;
	case IOBUF_T_BUF:
		if (*n > 0)
			buffer_read_buf(iobuf, (char*)v, *n, rpos);
		break;
	case IOBUF_T_7BIT:
		buffer_read_7bit_int(iobuf, (int*)v, rpos);
		break;
	default:
		assert(0);
	}
}

void buffer_format_readv(const char *iobuf, int* rpos, const char *fmt, va_list arg)
{
	if (fmt) {
		const char *p = fmt;
		while (*p) {
			switch (*p) {
			case '8':
				buffer_read(iobuf, IOBUF_T_I8, va_arg(arg, void*), NULL, rpos);
				break;
			case '7':  // 7bit int code
				buffer_read(iobuf, IOBUF_T_7BIT, va_arg(arg, void*), NULL, rpos);
				break;
			case '4':
				buffer_read(iobuf, IOBUF_T_I4, va_arg(arg, void*), 0, rpos);
				break;
			case '2':
				buffer_read(iobuf, IOBUF_T_I2, va_arg(arg, void*), 0, rpos);
				break;
			case '1':
				buffer_read(iobuf, IOBUF_T_I1, va_arg(arg, void*), 0, rpos);
				break;
			case 's':case 'S':
				{
					char **pstr = va_arg(arg, char**);
					int slen;
					buffer_read(iobuf, IOBUF_T_STR, NULL, &slen, rpos);
					//*pstr = (char*)malloc(slen+1);
					*pstr = new char[slen+1];
					buffer_read(iobuf, IOBUF_T_STR, *pstr, 0, rpos);
				}
				break;
			case 'w': case 'W':
				{
					wchar_t **pstr = va_arg(arg, wchar_t**);
					int slen;
					buffer_read(iobuf, IOBUF_T_WSTR, NULL, &slen, rpos);
//					*pstr = (wchar_t*)malloc(slen+2); // null terminated is two bytes
					*pstr = new wchar_t[slen+2];
					buffer_read(iobuf, IOBUF_T_WSTR, *pstr, 0, rpos);
				}
				break;
			case 'b':case 'B':
				{
					void *buf = va_arg(arg, void*);
					int size = va_arg(arg, int);
					buffer_read(iobuf, IOBUF_T_BUF, buf, &size, rpos);
				}
				break;
			default:
				assert(0);
				break;
			}
			p++;
		}
	}
}

class BufferFormatRead{
public:
	static void buffer_format_read(const char *iobuf, int* rpos, const char *fmt, ...)
	{
		va_list arg;
		va_start(arg, fmt);
		buffer_format_readv(iobuf, rpos, fmt, arg);
		va_end(arg);
	}
};


template<class T>
static inline void ReadT(const char *iobuf, T &t, int* rpos){
	int size = sizeof(t);
	buffer_read(iobuf, IOBUF_T_BUF, &t, &size, rpos);
}

static inline void ReadT(const char *iobuf, void* data, int &len, int* rpos){
	buffer_read(iobuf, IOBUF_T_BUF, data, &len, rpos);
}

template<class T>
static inline void ReadArrayT(const char *iobuf, CAutoArray<T> &t, int* rpos){
	int nArrayNum(0);
	buffer_read(iobuf, IOBUF_T_I4, &nArrayNum, NULL, rpos);

	if (nArrayNum >0)
	{
		t.Init(nArrayNum);

		for(int i=0; i<nArrayNum; i++)
		{
			ReadT(iobuf, t[i], rpos);
		}
	}
}

static inline void ReadT(const char *iobuf, CSimpleStringA &t, int* rpos){
	wchar_t *wt = NULL;
	BufferFormatRead::buffer_format_read(iobuf, rpos, "w", &wt); // string is unicode so we can compatible with silverlight
	CSimpleStringW wStr = wt;
	free(wt);
	t = CSimpleStringW2A(wStr);
}

static inline void ReadT(const char *iobuf, CSimpleStringW &t, int* rpos){
	wchar_t *wt = NULL;
	BufferFormatRead::buffer_format_read(iobuf, rpos, "w", &wt); // string is unicode so we can compatible with silverlight
	t = wt;
	free(wt);
}

/////////////////// Read Buf End///////////////////////


////////////////// Write Buffer Start /////////////////////

static void expand(char *iobuf, int head_capacity, int newcapacity, 
	int *capacity, int *hcapacity, int* rpos, int* wpos)
{
	if (head_capacity == -1) {
		int t = *capacity;
		while (newcapacity > t)
			t = t*2;
		if (t > *capacity) {
			iobuf = (char*)realloc(iobuf, t);
			*capacity = t;
		}
	} else if (newcapacity == -1) {
		int t = *hcapacity;
		while (head_capacity > t)
			t = t*2;
		if (t > *rpos) {
			char *new_data;
			int new_rpos;
			int new_wpos;
			newcapacity = *capacity + (t - *hcapacity);
//			new_data = (char*)malloc(newcapacity);
			new_data = new char[newcapacity];
			new_rpos = t;		
			new_wpos = new_rpos + (*wpos - *rpos);
			memcpy(new_data+new_rpos, iobuf+*rpos, *wpos - *rpos);
			free(iobuf);
			iobuf = new_data;
			*rpos = new_rpos;
			*wpos = new_wpos;
			*hcapacity  = t;
			*capacity = newcapacity;
		}
	} else {
		int t = *capacity;
//		char *new_data = (char*)malloc(t);
		char *new_data = new char[t];
		int new_rpos = head_capacity;
		int new_wpos = new_rpos + (*wpos - *rpos);
		while (newcapacity > t)
			t = t*2;
		memcpy(new_data+new_rpos, iobuf+*rpos, *wpos - *rpos);
		free(iobuf);
		iobuf = new_data;
		*rpos = new_rpos;
		*wpos = new_wpos;
		*capacity = t;
	}
}

static void buffer_write_buf(char *iobuf, const char *buf, int n, int* wpos, int* capacity)
{
	int rpos = 0;
	int hcapacity = 0;
	if ( n+(*wpos) > *capacity )
		expand(iobuf, -1, n + *wpos, capacity, &hcapacity, &rpos, wpos);
	memcpy(iobuf+*wpos, buf, n);
	*wpos += n;
}

static int write_7bit_int(unsigned char buf[8], unsigned int v)
{
	int i = 0;
	while (v >= 0x80) {
		buf[i++] = (unsigned char)(v | 0x80);		// set most left bit == 1 
		v >>= 7;
	}
	buf[i++] = (unsigned char)v;
	return i;
}

static void buffer_write_7bit_int(char *iobuf, unsigned int v, int* wpos, int* capacity)
{
	char buf[8];
	int n = write_7bit_int((unsigned char*)buf, v);
	buffer_write_buf(iobuf, buf, n, wpos, capacity);
}

void buffer_write(char *iobuf, int t, const void *v, int n, int* wpos, int* capacity)
{
	int len = 0;

	switch (t) {
	case IOBUF_T_I8:
		len += 8;
		buffer_write_buf(iobuf, (const char*)v, len, wpos, capacity);
		break;
	case IOBUF_T_I4:
		len += 4;
		buffer_write_buf(iobuf, (const char*)v, len, wpos, capacity);
		break;
	case IOBUF_T_I2:
		len += 2;
		buffer_write_buf(iobuf, (const char*)v, len, wpos, capacity);
		break;
	case IOBUF_T_I1:
		len += 1;
		buffer_write_buf(iobuf, (const char*)v, len, wpos, capacity);
		break;
	case IOBUF_T_STR:
		if (!v) {
			n = 0;
		} else {
			if (n == -1)
				n = strlen((const char*)v);
		}
		buffer_write_7bit_int(iobuf, (unsigned int)n,  wpos, capacity);
		if (n > 0)
			buffer_write_buf(iobuf, (const char*)v, n, wpos, capacity);
		break;
	case IOBUF_T_WSTR:
		if (!v) {
			n = 0;
		} else {
			if (n == -1)
				n = wcslen((const wchar_t*)v)<<1;
		}
		buffer_write_7bit_int(iobuf, n, wpos, capacity);
		if (n > 0)
			buffer_write_buf(iobuf, (const char*)v, n, wpos, capacity);
		break;
	case IOBUF_T_BUF:
		if (n > 0)
			buffer_write_buf(iobuf, (const char*)v, n, wpos, capacity);
		break;
	case IOBUF_T_7BIT:
		buffer_write_7bit_int(iobuf, *(unsigned int*)v, wpos, capacity);
		break;
	default:
		assert(0);
		break;
	}
}

template<class T>
static inline void WriteT(char *iobuf, T &t, int* wpos, int* capacity)
{
	buffer_write(iobuf, IOBUF_T_BUF, &t, sizeof(t), wpos, capacity);
}

template<class T>
static inline void WriteT(char *iobuf, const T &t)
{
	buffer_write(iobuf, IOBUF_T_BUF, &t, sizeof(t), wpos, capacity);
}


template<class T>
static inline void WriteArrayT(char *iobuf, CAutoArray<T> &t, int* wpos, int* capacity)
{
	int nArrayNum = t.GetCount();
	buffer_write(iobuf, IOBUF_T_I4, &nArrayNum, 0, wpos, capacity);

	for(int i=0; i<nArrayNum; i++)
	{
		WriteT(iobuf, t[i], wpos, capacity);
	}
}

template<class T>
static inline void WriteArrayT(char *iobuf, const CAutoArray<T> &t, int* wpos, int* capacity)
{
	int nArrayNum = t.GetCount();
	buffer_write(iobuf, IOBUF_T_I4, &nArrayNum, 0, wpos, capacity);

	for(int i=0; i<nArrayNum; i++)
	{
		WriteT(iobuf, t[i], wpos, capacity);
	}
}

static inline void WriteT(char *iobuf, CSimpleStringA &t, int* wpos, int* capacity)
{
	CSimpleStringW wt = CSimpleStringA2W(t); // string is unicode so we can compatible with silverlight
	buffer_write(iobuf, IOBUF_T_WSTR, wt.GetData(), -1, wpos, capacity);
}


static inline void WriteT(char *iobuf, CSimpleStringW &t, int* wpos, int* capacity)
{
	buffer_write(iobuf, IOBUF_T_WSTR, t.GetData(), -1, wpos, capacity);
}

static inline void WriteT(char *iobuf, const CSimpleStringA &t, int* wpos, int* capacity)
{
	CSimpleStringW wt = CSimpleStringA2W(t); // string is unicode so we can compatible with silverlight
	buffer_write(iobuf, IOBUF_T_WSTR, wt.GetData(), -1, wpos, capacity);
}

static inline void WriteT(char *iobuf, const CSimpleStringW &t, int* wpos, int* capacity)
{
	buffer_write(iobuf, IOBUF_T_WSTR, t.GetData(), -1, wpos, capacity);
}

static inline void WriteT(char *iobuf, char* t, int* wpos, int* capacity, int len)
{
	buffer_write(iobuf, IOBUF_T_BUF, t, len, wpos, capacity);
}


// static inline void WriteT(char *iobuf, CBlob &t)
// {
// // 	iobuffer_write(iobuf, IOBUF_T_I4, &t.m_iLength, 0);
// // 	iobuffer_write(iobuf, IOBUF_T_BUF, t.m_pData, t.m_iLength);
// }
// 
// 
// static inline void WriteT(char *iobuf, const CBlob &t)
// {
// // 	iobuffer_write(iobuf, IOBUF_T_I4, &t.m_iLength, 0);
// // 	iobuffer_write(iobuf, IOBUF_T_BUF, t.m_pData, t.m_iLength);
// }

/////////////////  Write Buffer End //////////////////////

}

#endif