关于uboot中tftp上传内存数据到tftp服务器

uboot下的tftp下载功能是非常重要和常见的功能。但是偶尔有些特殊需求的人需要使用uboot的tftp具有上传功能。
默认的uboot没有tftp上传功能，如果需要修改uboot代码。
使用时键入第4个参数，则不同于3个参数的tftp下载功能。
#tftp 50400000 xx.bin 10000
TFTP to server 192.168.0.30; our IP address is 192.168.0.152
Upload Filename 'xx.bin'.
Upload from address: 0x50400000, 0.064 MB to be send ...
Uploading: %#   [ Connected ]

         0.064 MB upload ok.
这条命令将板子上0x50400000 开始，长度0x10000的数据上传到远程tftp服务器，命名为xx.bin

这个修改在uboot1.3.4和2008.10版本上测试通过。
1、修改common/cmd_net.c 
注释掉

/*
int do_tftpb (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
    return netboot_common (TFTP, cmdtp, argc, argv);
}

U_BOOT_CMD(
    tftpboot,    3,    1,    do_tftpb,
    "tftpboot- boot image via network using TFTP protocol
",
    "[loadAddress] [[hostIPaddr:]bootfilename]
"
);
*/

可以看出默认uboot执行tftp命令其实调用的是tftpboot，uboot果然是看命名的前面几个字母而不是全名。例如print命令只需要键入pri。
接着添加

int do_tftp (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
    return netboot_common (TFTP, cmdtp, argc, argv);
}

U_BOOT_CMD(
    tftp,    4,    1,    do_tftp,
    "tftp	- download or upload image via network using TFTP protocol
",
    "[loadAddress] [bootfilename] <upload_size>
"
);

然后修改netboot_common成如下代码

static int
netboot_common (proto_t proto, cmd_tbl_t *cmdtp, int argc, char *argv[])
{
    extern ulong upload_addr;
    extern ulong upload_size;

    char *s;
    int rcode = 0;
    int size;

    /* pre-set load_addr */
    if ((s = getenv("loadaddr")) != NULL) {
        load_addr = simple_strtoul(s, NULL, 16);
    }

    switch (argc) {
    case 1:
        break;

    case 2:    /* only one arg - accept two forms:
         * just load address, or just boot file name.
         * The latter form must be written "filename" here.
         */
        if (argv[1][0] == '"') {    /* just boot filename */
            copy_filename (BootFile, argv[1], sizeof(BootFile));
        } else {            /* load address    */
            load_addr = simple_strtoul(argv[1], NULL, 16);
        }
        break;

    case 3:    load_addr = simple_strtoul(argv[1], NULL, 16);
        copy_filename (BootFile, argv[2], sizeof(BootFile));
        upload_size = 0;

        break;

    case 4:
        upload_addr = simple_strtoul(argv[1], NULL, 16);
        upload_size = simple_strtoul(argv[3], NULL, 16);
        copy_filename (BootFile, argv[2], sizeof(BootFile));

        break;

    default: printf ("Usage:
%s
", cmdtp->usage);
        show_boot_progress (-80);
        return 1;
    }

    show_boot_progress (80);
    if ((size = NetLoop(proto)) < 0) {
        show_boot_progress (-81);
        return 1;
    }

    show_boot_progress (81);
    /* NetLoop ok, update environment */
    netboot_update_env();

    /* done if no file was loaded (no errors though) */
    if (size == 0) {
        show_boot_progress (-82);
        return 0;
    }

    /* flush cache */
    flush_cache(load_addr, size);

    /* Loading ok, check if we should attempt an auto-start */
    if (((s = getenv("autostart")) != NULL) && (strcmp(s,"yes") == 0)) {
        char *local_args[2];
        local_args[0] = argv[0];
        local_args[1] = NULL;

        printf ("Automatic boot of image at addr 0x%08lX ...
",
            load_addr);
        show_boot_progress (82);
        rcode = do_bootm (cmdtp, 0, 1, local_args);
    }

#ifdef CONFIG_AUTOSCRIPT
    if (((s = getenv("autoscript")) != NULL) && (strcmp(s,"yes") == 0)) {
        printf ("Running autoscript at addr 0x%08lX", load_addr);

        s = getenv ("autoscript_uname");
        if (s)
            printf (":%s ...
", s);
        else
            puts (" ...
");

        show_boot_progress (83);
        rcode = autoscript (load_addr, s);
    }
#endif
    if (rcode < 0)
        show_boot_progress (-83);
    else
        show_boot_progress (84);
    return rcode;
}

2、修改net/tftp.c 为

/*
* Copyright 1994, 1995, 2000 Neil Russell.
* (See License)
* Copyright 2000, 2001 DENX Software Engineering, Wolfgang Denk, wd@denx.de
*/

#include <common.h>
#include <command.h>
#include <net.h>
#include "tftp.h"
#include "bootp.h"

#undef ET_DEBUG

#if defined(CONFIG_CMD_NET)

#define WELL_KNOWN_PORT 69 /* Well known TFTP port # */
#define TIMEOUT 1 /* Seconds to timeout for a lost pkt */
#ifndef CONFIG_NET_RETRY_COUNT
# define TIMEOUT_COUNT 10 /* # of timeouts before giving up */
#else
# define TIMEOUT_COUNT (CONFIG_NET_RETRY_COUNT * 2)
#endif
/* (for checking the image size) */
#define TBLKS_PER_HASHES 64
#define HASHES_PER_LINE 32 /* Number of "loading" hashes per line */

/*
* TFTP operations.
*/
#define TFTP_RRQ 1
#define TFTP_WRQ 2
#define TFTP_DATA 3
#define TFTP_ACK 4
#define TFTP_ERROR 5
#define TFTP_OACK 6

#define STATE_OK 0
#define STATE_ERROR 3
#define STATE_WRQ 6
#define STATE_ACK 7

static IPaddr_t TftpServerIP;
static int TftpServerPort; /* The UDP port at their end */
static int TftpOurPort; /* The UDP port at our end */
static int TftpTimeoutCount;
static ulong TftpBlock; /* packet sequence number */
static ulong TftpLastBlock; /* last packet sequence number received */
static ulong TftpBlockWrap; /* count of sequence number wraparounds */
static ulong TftpBlockWrapOffset; /* memory offset due to wrapping */
static int TftpState;

#define STATE_RRQ 1
#define STATE_DATA 2
#define STATE_TOO_LARGE 3
#define STATE_BAD_MAGIC 4
#define STATE_OACK 5

#define TFTP_BLOCK_SIZE 512 /* default TFTP block size */
#define TFTP_SEQUENCE_SIZE ((ulong)(1<<16)) /* sequence number is 16 bit */

#define DEFAULT_NAME_LEN (8 + 4 + 1)
static char default_filename[DEFAULT_NAME_LEN];

#ifndef CONFIG_TFTP_FILE_NAME_MAX_LEN
#define MAX_LEN 128
#else
#define MAX_LEN CONFIG_TFTP_FILE_NAME_MAX_LEN
#endif

static char tftp_filename[MAX_LEN];

#ifdef CFG_DIRECT_FLASH_TFTP
extern flash_info_t flash_info[];
#endif

ulong upload_addr = CFG_LOAD_ADDR; /* Default upLoad Address */
ulong upload_size = 0;

/* 512 is poor choice for ethernet, MTU is typically 1500.
* Minus eth.hdrs thats 1468. Can get 2x better throughput with
* almost-MTU block sizes. At least try... fall back to 512 if need be.
*/
#define TFTP_MTU_BLOCKSIZE 1468
static unsigned short TftpBlkSize=TFTP_BLOCK_SIZE;
static unsigned short TftpBlkSizeOption=TFTP_MTU_BLOCKSIZE;

#ifdef CONFIG_MCAST_TFTP
#include <malloc.h>
#define MTFTP_BITMAPSIZE 0x1000
static unsigned *Bitmap;
static int PrevBitmapHole,Mapsize=MTFTP_BITMAPSIZE;
static uchar ProhibitMcast=0, MasterClient=0;
static uchar Multicast=0;
extern IPaddr_t Mcast_addr;
static int Mcast_port;
static ulong TftpEndingBlock; /* can get 'last' block before done..*/

static void parse_multicast_oack(char *pkt,int len);

static void
mcast_cleanup(void)
{
if (Mcast_addr) eth_mcast_join(Mcast_addr, 0);
if (Bitmap) free(Bitmap);
Bitmap=NULL;
Mcast_addr = Multicast = Mcast_port = 0;
TftpEndingBlock = -1;
}

#endif /* CONFIG_MCAST_TFTP */

static __inline__ void
store_block (unsigned block, uchar * src, unsigned len)
{
ulong offset = block * TftpBlkSize + TftpBlockWrapOffset;
ulong newsize = offset + len;
#ifdef CFG_DIRECT_FLASH_TFTP
int i, rc = 0;

for (i=0; i<CFG_MAX_FLASH_BANKS; i++) {
/* start address in flash? */
if (flash_info[i].flash_id == FLASH_UNKNOWN)
continue;
if ((load_addr + offset >= flash_info[i].start[0]) && (load_addr + offset < flash_info[i].start[0] + flash_info[i].size)) {
rc = 1;
break;
}
}

if (rc) { /* Flash is destination for this packet */
rc = flash_write ((char *)src, (ulong)(load_addr+offset), len);
if (rc) {
flash_perror (rc);
NetState = NETLOOP_FAIL;
return;
}
}
else
#endif /* CFG_DIRECT_FLASH_TFTP */
{
(void)memcpy((void *)(load_addr + offset), src, len);
}
#ifdef CONFIG_MCAST_TFTP
if (Multicast)
ext2_set_bit(block, Bitmap);
#endif

if (NetBootFileXferSize < newsize)
NetBootFileXferSize = newsize;
}

static void TftpSend (void);
static void TftpTimeout (void);

/**********************************************************************/

static void
TftpSend (void)
{
volatile uchar * pkt;
volatile uchar * xp;
int len = 0;
int uplen=0;
volatile ushort *s;

#ifdef CONFIG_MCAST_TFTP
/* Multicast TFTP.. non-MasterClients do not ACK data. */
if (Multicast
&& (TftpState == STATE_DATA)
&& (MasterClient == 0))
return;
#endif
/*
* We will always be sending some sort of packet, so
* cobble together the packet headers now.
*/
pkt = NetTxPacket + NetEthHdrSize() + IP_HDR_SIZE;

switch (TftpState) {

case STATE_RRQ:
case STATE_WRQ:
xp = pkt;

s = (ushort *)pkt;
if(TftpState == STATE_WRQ)
*s++ = htons(TFTP_WRQ);
else *s++ = htons(TFTP_RRQ);
pkt = (uchar *)s;
strcpy ((char *)pkt, tftp_filename);
pkt += strlen(tftp_filename) + 1;
strcpy ((char *)pkt, "octet");
pkt += 5 /*strlen("octet")*/ + 1;
strcpy ((char *)pkt, "timeout");
pkt += 7 /*strlen("timeout")*/ + 1;
sprintf((char *)pkt, "%d", TIMEOUT);
#ifdef ET_DEBUG
printf("send option "timeout %s"
", (char *)pkt);
#endif
pkt += strlen((char *)pkt) + 1;
/* try for more effic. blk size */
if(TftpState == STATE_WRQ)
pkt += sprintf((char *)pkt,"blksize%c%d%c",
0,TftpBlkSizeOption,0);
else
pkt += sprintf((char *)pkt,"blksize%c%d%c",
0,TftpBlkSizeOption,0);

#ifdef CONFIG_MCAST_TFTP
/* Check all preconditions before even trying the option */
if (!ProhibitMcast
&& (Bitmap=malloc(Mapsize))
&& eth_get_dev()->mcast) {
free(Bitmap);
Bitmap=NULL;
pkt += sprintf((char *)pkt,"multicast%c%c",0,0);
}
#endif /* CONFIG_MCAST_TFTP */
len = pkt - xp;
printf("%%");
break;

case STATE_OACK:
#ifdef CONFIG_MCAST_TFTP
/* My turn! Start at where I need blocks I missed.*/
if (Multicast)
TftpBlock=ext2_find_next_zero_bit(Bitmap,(Mapsize*8),0);
/*..falling..*/
#endif
case STATE_DATA:
xp = pkt;
s = (ushort *)pkt;
*s++ = htons(TFTP_ACK);
*s++ = htons(TftpBlock);
pkt = (uchar *)s;
len = pkt - xp;
break;

case STATE_TOO_LARGE:
xp = pkt;
s = (ushort *)pkt;
*s++ = htons(TFTP_ERROR);
*s++ = htons(3);
pkt = (uchar *)s;
strcpy ((char *)pkt, "File too large");
pkt += 14 /*strlen("File too large")*/ + 1;
len = pkt - xp;
break;

case STATE_BAD_MAGIC:
xp = pkt;
s = (ushort *)pkt;
*s++ = htons(TFTP_ERROR);
*s++ = htons(2);
pkt = (uchar *)s;
strcpy ((char *)pkt, "File has bad magic");
pkt += 18 /*strlen("File has bad magic")*/ + 1;
len = pkt - xp;
break;
case STATE_ACK:
xp = pkt;
s = (ushort *)pkt;
*s++ = htons(TFTP_DATA);
*s++ = htons(TftpBlock+1);
pkt = (uchar *)s;

uplen = (upload_size-TftpBlock*TftpBlkSize);
uplen = uplen > TftpBlkSize ? TftpBlkSize : uplen;
memcpy((void*)pkt, (const char*)upload_addr + TftpBlock*TftpBlkSize , uplen);
pkt += uplen;
len = pkt - xp;
break;
default:
return;
}

NetSendUDPPacket(NetServerEther, TftpServerIP, TftpServerPort, TftpOurPort, len);
}

static void tftp_show_transferd(int block, unsigned long wrap)
{
#define SHOW_TRANSFERD(tail) printf ("	[%2lu.%03lu MB]%s", ((block-1)* TftpBlkSize + wrap)>>20,
(((block-1) * TftpBlkSize + wrap)&0x0FFFFF)>>10, tail)

if( ((block-1) & (TBLKS_PER_HASHES-1)) == 0)
putc('#');

if( ((block-1) & (TBLKS_PER_HASHES*HASHES_PER_LINE-1)) == 0) {
if((block-1) ==0) {
if(wrap==0) {
puts("	[ Connected ]
");
} else {
SHOW_TRANSFERD(" [BlockCounter Reset]
");
}
} else {
SHOW_TRANSFERD("
");
}
}
#undef SHOW_TRANSFERD
}

static void
TftpHandler (uchar * pkt, unsigned dest, unsigned src, unsigned len)
{
ushort proto;
ushort *s;
int i;

if (dest != TftpOurPort) {
#ifdef CONFIG_MCAST_TFTP
if (Multicast
&& (!Mcast_port || (dest != Mcast_port)))
#endif
return;
}
if ( !(TftpState==STATE_RRQ || TftpState==STATE_WRQ) && src != TftpServerPort) {
return;
}

if (len < 2) {
return;
}
len -= 2;
/* warning: don't use increment (++) in ntohs() macros!! */
s = (ushort *)pkt;
proto = *s++;
pkt = (uchar *)s;
switch (ntohs(proto)) {

case TFTP_RRQ:
case TFTP_WRQ:
break;
case TFTP_ACK:
TftpServerPort = src;
TftpState=STATE_ACK;
TftpBlock = ntohs(*(ushort *)pkt);
if(TftpLastBlock == TftpBlock) {
putc('%');
} else {
tftp_show_transferd(TftpBlock, TftpBlockWrapOffset);
}
TftpLastBlock = TftpBlock;
NetSetTimeout (TIMEOUT * CFG_HZ, TftpTimeout);

if(TftpBlkSize*TftpBlock> upload_size )
{
NetState = NETLOOP_SUCCESS;
TftpState = STATE_OK;
printf ("
	 %lu.%03lu MB upload ok.
", (TftpBlockWrapOffset+upload_size)>>20,
((TftpBlockWrapOffset+upload_size)&0x0FFFFF)>>10);
break;
}
TftpSend (); /* Send ACK */
break;
default:
break;

case TFTP_OACK:
#ifdef ET_DEBUG
printf("Got OACK: %s %s
", pkt, pkt+strlen(pkt)+1);
#endif
if(TftpState == STATE_WRQ)
{
TftpState = STATE_ACK;
TftpBlock = 0;
}
else
{
TftpState = STATE_OACK;
}
TftpServerPort = src;
/*
* Check for 'blksize' option.
* Careful: "i" is signed, "len" is unsigned, thus
* something like "len-8" may give a *huge* number
*/
for (i=0; i+8<len; i++) {
if (strcmp ((char*)pkt+i,"blksize") == 0) {
TftpBlkSize = (unsigned short)
simple_strtoul((char*)pkt+i+8,NULL,10);
#ifdef ET_DEBUG
printf ("Blocksize ack: %s, %d
",
(char*)pkt+i+8,TftpBlkSize);
#endif
break;
}
}
#ifdef CONFIG_MCAST_TFTP
parse_multicast_oack((char *)pkt,len-1);
if ((Multicast) && (!MasterClient))
TftpState = STATE_DATA; /* passive.. */
else
#endif
TftpSend (); /* Send ACK */
break;
case TFTP_DATA:
if (len < 2)
return;
len -= 2;
TftpBlock = ntohs(*(ushort *)pkt);

/*
* RFC1350 specifies that the first data packet will
* have sequence number 1. If we receive a sequence
* number of 0 this means that there was a wrap
* around of the (16 bit) counter.
*/
if (TftpBlock == 0) {
TftpBlockWrap++;
TftpBlockWrapOffset += TftpBlkSize * TFTP_SEQUENCE_SIZE;
printf ("
	 %lu MB received
	 ", TftpBlockWrapOffset>>20);
} else {
#if 0
if (((TftpBlock - 1) % 10) == 0) {
putc ('#');
} else if ((TftpBlock % (10 * HASHES_PER_LINE)) == 0) {
puts ("
	 ");
}
#endif
tftp_show_transferd(TftpBlock, TftpBlockWrapOffset);
}

#ifdef ET_DEBUG
if (TftpState == STATE_RRQ) {
puts ("Server did not acknowledge timeout option!
");
}
#endif

if (TftpState == STATE_RRQ || TftpState == STATE_OACK) {
/* first block received */
TftpState = STATE_DATA;
TftpServerPort = src;
TftpLastBlock = 0;
TftpBlockWrap = 0;
TftpBlockWrapOffset = 0;

#ifdef CONFIG_MCAST_TFTP
if (Multicast) { /* start!=1 common if mcast */
TftpLastBlock = TftpBlock - 1;
} else
#endif
if (TftpBlock != 1) { /* Assertion */
printf ("
TFTP error: "
"First block is not block 1 (%ld)
"
"Starting again

",
TftpBlock);
NetStartAgain ();
break;
}
}

if (TftpBlock == TftpLastBlock) {
/*
* Same block again; ignore it.
*/
putc ('%');
break;
}

TftpLastBlock = TftpBlock;
NetSetTimeout (TIMEOUT * CFG_HZ, TftpTimeout);

store_block (TftpBlock - 1, pkt + 2, len);

/*
* Acknoledge the block just received, which will prompt
* the server for the next one.
*/
#ifdef CONFIG_MCAST_TFTP
/* if I am the MasterClient, actively calculate what my next
* needed block is; else I'm passive; not ACKING
*/
if (Multicast) {
if (len < TftpBlkSize) {
TftpEndingBlock = TftpBlock;
} else if (MasterClient) {
TftpBlock = PrevBitmapHole =
ext2_find_next_zero_bit(
Bitmap,
(Mapsize*8),
PrevBitmapHole);
if (TftpBlock > ((Mapsize*8) - 1)) {
printf ("tftpfile too big
");
/* try to double it and retry */
Mapsize<<=1;
mcast_cleanup();
NetStartAgain ();
return;
}
TftpLastBlock = TftpBlock;
}
}
#endif
TftpSend ();

#ifdef CONFIG_MCAST_TFTP
if (Multicast) {
if (MasterClient && (TftpBlock >= TftpEndingBlock)) {
puts ("
Multicast tftp done
");
mcast_cleanup();
NetState = NETLOOP_SUCCESS;
}
}
else
#endif
if (len < TftpBlkSize) {
/*
* We received the whole thing. Try to
* run it.
*/
printf ("
	 %lu.%03lu MB download ok.
", ((TftpBlock-1)* TftpBlkSize + TftpBlockWrapOffset)>>20,
(((TftpBlock-1) * TftpBlkSize + TftpBlockWrapOffset)&0x0FFFFF)>>10);
puts ("
done
");
NetState = NETLOOP_SUCCESS;
}
break;

case TFTP_ERROR:
printf ("
TFTP error: '%s' (%d)
",
pkt + 2, ntohs(*(ushort *)pkt));
puts ("Starting again

");
#ifdef CONFIG_MCAST_TFTP
mcast_cleanup();
#endif
NetStartAgain ();
break;
}
}


static void
TftpTimeout (void)
{
if (++TftpTimeoutCount > TIMEOUT_COUNT) {
puts ("
Retry count exceeded; starting again
");
#ifdef CONFIG_MCAST_TFTP
mcast_cleanup();
#endif
NetStartAgain ();
} else {
puts ("T ");
NetSetTimeout (TIMEOUT * CFG_HZ, TftpTimeout);
TftpSend ();
}
}


void
TftpStart (void)
{
#ifdef CONFIG_TFTP_PORT
char *ep; /* Environment pointer */
#endif

if(upload_size)
TftpState = STATE_WRQ;
else TftpState = STATE_RRQ;

TftpServerIP = NetServerIP;
if (BootFile[0] == '') {
sprintf(default_filename, "%02lX%02lX%02lX%02lX.img",
NetOurIP & 0xFF,
(NetOurIP >> 8) & 0xFF,
(NetOurIP >> 16) & 0xFF,
(NetOurIP >> 24) & 0xFF );

strncpy(tftp_filename, default_filename, MAX_LEN);
tftp_filename[MAX_LEN-1] = 0;

printf ("*** Warning: no boot file name; using '%s'
",
tftp_filename);
} else {
char *p = strchr (BootFile, ':');

if (p == NULL) {
strncpy(tftp_filename, BootFile, MAX_LEN);
tftp_filename[MAX_LEN-1] = 0;
} else {
*p++ = '';
TftpServerIP = string_to_ip (BootFile);
strncpy(tftp_filename, p, MAX_LEN);
tftp_filename[MAX_LEN-1] = 0;
}
}

#if defined(CONFIG_NET_MULTI)
printf ("Using %s device
", eth_get_name());
#endif
if( TftpState == STATE_WRQ)
{
puts ("TFTP to server "); print_IPaddr (NetServerIP);
}
else
{
puts ("TFTP from server "); print_IPaddr (TftpServerIP);
}
puts ("; our IP address is "); print_IPaddr (NetOurIP);

/* Check if we need to send across this subnet */
if (NetOurGatewayIP && NetOurSubnetMask) {
IPaddr_t OurNet = NetOurIP & NetOurSubnetMask;
IPaddr_t ServerNet = TftpServerIP & NetOurSubnetMask;

if (OurNet != ServerNet) {
puts ("; sending through gateway ");
print_IPaddr (NetOurGatewayIP) ;
}
}
putc ('
');

if( TftpState == STATE_WRQ)
printf ("Upload Filename '%s'.", tftp_filename);
else printf ("Download Filename '%s'.", tftp_filename);

if (NetBootFileSize) {
printf (" Size is 0x%x Bytes = ", NetBootFileSize<<9);
print_size (NetBootFileSize<<9, "");
}

putc ('
');

if( TftpState == STATE_WRQ)
{
printf ("Upload from address: 0x%lx, ", upload_addr);
printf ("%lu.%03lu MB to be send ...
", upload_size>>20, (upload_size&0x0FFFFF)>>10);
printf ("Uploading: *");
}
else
{
printf ("Download to address: 0x%lx
", load_addr);
printf ("Downloading: *");
}

NetSetTimeout (TIMEOUT * CFG_HZ, TftpTimeout);
NetSetHandler (TftpHandler);

TftpServerPort = WELL_KNOWN_PORT;
TftpTimeoutCount = 0;
/* Use a pseudo-random port unless a specific port is set */
TftpOurPort = 1024 + (get_timer(0) % 3072);

#ifdef CONFIG_TFTP_PORT
if ((ep = getenv("tftpdstp")) != NULL) {
TftpServerPort = simple_strtol(ep, NULL, 10);
}
if ((ep = getenv("tftpsrcp")) != NULL) {
TftpOurPort= simple_strtol(ep, NULL, 10);
}
#endif
TftpBlock = 0;

TftpLastBlock = 0;
TftpBlockWrap = 0;
TftpBlockWrapOffset = 0;

/* zero out server ether in case the server ip has changed */
memset(NetServerEther, 0, 6);
/* Revert TftpBlkSize to dflt */
TftpBlkSize = TFTP_BLOCK_SIZE;
#ifdef CONFIG_MCAST_TFTP
mcast_cleanup();
#endif

TftpSend ();
}

#ifdef CONFIG_MCAST_TFTP
/* Credits: atftp project.
*/

/* pick up BcastAddr, Port, and whether I am [now] the master-client. *
* Frame:
* +-------+-----------+---+-------~~-------+---+
* | opc | multicast | 0 | addr, port, mc | 0 |
* +-------+-----------+---+-------~~-------+---+
* The multicast addr/port becomes what I listen to, and if 'mc' is '1' then
* I am the new master-client so must send ACKs to DataBlocks. If I am not
* master-client, I'm a passive client, gathering what DataBlocks I may and
* making note of which ones I got in my bitmask.
* In theory, I never go from master->passive..
* .. this comes in with pkt already pointing just past opc
*/
static void parse_multicast_oack(char *pkt, int len)
{
int i;
IPaddr_t addr;
char *mc_adr, *port, *mc;

mc_adr=port=mc=NULL;
/* march along looking for 'multicast', which has to start at least
* 14 bytes back from the end.
*/
for (i=0;i<len-14;i++)
if (strcmp (pkt+i,"multicast") == 0)
break;
if (i >= (len-14)) /* non-Multicast OACK, ign. */
return;

i+=10; /* strlen multicast */
mc_adr = pkt+i;
for (;i<len;i++) {
if (*(pkt+i) == ',') {
*(pkt+i) = '';
if (port) {
mc = pkt+i+1;
break;
} else {
port = pkt+i+1;
}
}
}
if (!port || !mc_adr || !mc ) return;
if (Multicast && MasterClient) {
printf ("I got a OACK as master Client, WRONG!
");
return;
}
/* ..I now accept packets destined for this MCAST addr, port */
if (!Multicast) {
if (Bitmap) {
printf ("Internal failure! no mcast.
");
free(Bitmap);
Bitmap=NULL;
ProhibitMcast=1;
return ;
}
/* I malloc instead of pre-declare; so that if the file ends
* up being too big for this bitmap I can retry
*/
if (!(Bitmap = malloc (Mapsize))) {
printf ("No Bitmap, no multicast. Sorry.
");
ProhibitMcast=1;
return;
}
memset (Bitmap,0,Mapsize);
PrevBitmapHole = 0;
Multicast = 1;
}
addr = string_to_ip(mc_adr);
if (Mcast_addr != addr) {
if (Mcast_addr)
eth_mcast_join(Mcast_addr, 0);
if (eth_mcast_join(Mcast_addr=addr, 1)) {
printf ("Fail to set mcast, revert to TFTP
");
ProhibitMcast=1;
mcast_cleanup();
NetStartAgain();
}
}
MasterClient = (unsigned char)simple_strtoul((char *)mc,NULL,10);
Mcast_port = (unsigned short)simple_strtoul(port,NULL,10);
printf ("Multicast: %s:%d [%d]
", mc_adr, Mcast_port, MasterClient);
return;
}

#endif /* Multicast TFTP */

#endif

 

 

来自：http://blog.chinaunix.net/uid-20737871-id-2124122.html