XCOSnTh—YModem

XCOSnTh是一个开源的shell，由笔者设计

#include"XCOSnTh.h"
#include"YModem.h"
YModemRx YModemR;
/*
* XShell在YModem传输开始的时候会发送一个rb -E
* 此时需要Ymodem的接收方，回一个传输请求C(0x43)
* void (*RxInfo)(char *fileName,unsigned int fileSize)
* void (*RxSave)(unsigned char *rxBytes,int rxLength)
*/
unsigned char rxbuff[1024+5];
static int rxCount = 0;
static volatile unsigned int remainingLength;//剩余接收长度
static int calcrc(unsigned char *ptr, int count)
{
	int crc, i;
	crc = 0;
	while (--count >= 0) 
	{
		crc = crc ^ (int)*ptr++ << 8;
		for (i = 0; i < 8; ++i)
		{
			if (crc & 0x8000)
			{
				crc = crc << 1 ^ 0x1021;//0x1021是CRC多项式
			}
			else
			{
				crc = crc << 1;
			}
		}
	}
	return (crc & 0xFFFF);
}
static int ATOI(char *string)
{
	int i=0;
	int rtn=0;
	while(string[i]!=0)
	{
		rtn*=10;
		rtn+=(string[i]-'0');
		i++;
	}
	return rtn;
}
static int CMD_ymodemRx_exe(CmdObj obj, char* str, int len)
{
	int rxByte;
	int length=1;
	int headerFlag=0;
	unsigned char a;
	int crc=1;
	YModemRxObj ymodemObj=&YModemR;
	ymodemObj->printf = obj->printf;
	ymodemObj->fifo_pop=(int (*)())ShellRegisterFormFind( "Root", "CMD_FIFO_POP");//从注册表中并获取pop函数
	ymodemObj->printf("YModemRxing");
	//1、响应C
	while (ymodemObj->fifo_pop() != 0x0D);
	ymodemObj->printf("\x43");//ymodemObj->printf("C");//2种写法是一样的
	
	//2、接收数据帧
	while (1)
	{
		for (rxCount = 0, length=1; rxCount < length; )
		{
			rxByte = ymodemObj->fifo_pop();
			if (rxByte >= 0)
			{
				rxbuff[rxCount++] = rxByte;
				if (rxbuff[0] == 1)
				{
					if(headerFlag==0){headerFlag=1;}
					length = 128 + 5;
				}
				else if (rxbuff[0] == 2)
				{
					if(headerFlag==0){headerFlag=1;}
					length = 1024 + 5;
				}
				else if (rxbuff[0] == 4)
				{//接收流程结束
					if(ymodemObj->RxDatasEND)
					{
						ymodemObj->RxDatasEND();
					}
					break;
				}
			}
		}
		/
		a=~rxbuff[2];
		if ((rxbuff[0] == 1)&&(rxbuff[1]==a))
		{
			if(headerFlag==1)
			{
				headerFlag=2;
				if(ymodemObj->RxInfo)
				{//接收的文件名和大小
					int i=3,j=0;
					for(;;){if(rxbuff[i++]==0){break;}}
					for(;;){if(rxbuff[i+j++]==0x20){break;}}
					rxbuff[i+j-1]=0;
					crc=calcrc(&rxbuff[3],128);//归零CRC //数据头不进行CRC校验
					remainingLength=ATOI((char*)&rxbuff[i]);
					ymodemObj->RxInfo((char*)&rxbuff[3],remainingLength);//首次剩余接收长度表示文件大小
				}
			}
			else
			{
				if (ymodemObj->RxSave)
				{
					crc=calcrc(&rxbuff[3],128+2);//归零CRC
					if(crc==0)
					{
						if(remainingLength>128)
						{
							ymodemObj->RxSave(&rxbuff[3],128);
							remainingLength-=128;
						}
						else
						{
							ymodemObj->RxSave(&rxbuff[3],remainingLength);
						}
					}
				}
			}
		}
		else if ((rxbuff[0] == 2)&&(rxbuff[1]==a))
		{
			if(headerFlag==1)
			{//接收的文件名和大小
				int i=3,j=0;
				for(;;){if(rxbuff[i++]==0){break;}}
				for(;;){if(rxbuff[i+j++]==0x20){break;}}
				rxbuff[i+j-1]=0;
				ymodemObj->RxInfo((char*)&rxbuff[3],ATOI((char*)&rxbuff[i]));
			}
			else
			{
				if (ymodemObj->RxSave)
				{
					ymodemObj->RxSave(&rxbuff[3], 128);
				}
			}
		}
		else if (rxbuff[0] == 4)
		{
			break;
		}
		ymodemObj->printf("\x06");
	}
	//4、接收结束流程
	ymodemObj->printf("\x15");
	while (ymodemObj->fifo_pop() != 0x04);
	ymodemObj->printf("\x06");
	ymodemObj->printf("\x43");
	while (ymodemObj->fifo_pop() != 0x01);
	ymodemObj->printf("\x06");
	ymodemObj->printf("\x4F");
	while (ymodemObj->fifo_pop() != 0x18);
	ymodemObj->printf("\r\n...");
	if(ymodemObj->RxEND)
	{
		ymodemObj->RxEND(obj->printf);
	}
	ymodemObj->printf("\r\nEND");
	return 0;
}
CmdDef(ymodemRx, "接收文件", CMD_ymodemRx_exe, "YModem接收文件");

#ifndef YModem_h
#define YModem_h
typedef struct
{
	int (*fifo_pop)();
	int(*printf)(const char* format, ...);
	void (*RxInfo)(char* fileName, unsigned int fileSize);
	void (*RxSave)(unsigned char* rxBytes, int rxLength);
	void (*RxDatasEND)(void);//接收数据结束
	void (*RxEND)(int(*printf)(const char* format, ...));//整个接收流程结束
}YModemRx, * YModemRxObj;
extern YModemRx YModemR;
#endif