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/* |
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* Copyright (c) 1995 Danny Gasparovski. |
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* |
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* Please read the file COPYRIGHT for the |
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* terms and conditions of the copyright. |
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*/ |
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|
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#include <stdlib.h> |
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#include <slirp.h> |
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|
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/* Done as a macro in socket.h */ |
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/* int |
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* sbspace(struct sockbuff *sb) |
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* { |
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* return SB_DATALEN - sb->sb_cc; |
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* } |
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*/ |
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|
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void |
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sbfree(sb) |
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struct sbuf *sb; |
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{ |
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free(sb->sb_data); |
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} |
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|
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void |
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sbdrop(sb, num) |
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struct sbuf *sb; |
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int num; |
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{ |
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/* |
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* We can only drop how much we have |
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* This should never succeed |
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*/ |
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if(num > sb->sb_cc) |
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num = sb->sb_cc; |
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sb->sb_cc -= num; |
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sb->sb_rptr += num; |
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if(sb->sb_rptr >= sb->sb_data + sb->sb_datalen) |
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sb->sb_rptr -= sb->sb_datalen; |
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|
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} |
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|
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void |
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sbreserve(sb, size) |
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struct sbuf *sb; |
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int size; |
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{ |
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if (sb->sb_data) { |
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/* Already alloced, realloc if necessary */ |
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if (sb->sb_datalen != size) { |
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sb->sb_wptr = sb->sb_rptr = sb->sb_data = (char *)realloc(sb->sb_data, size); |
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sb->sb_cc = 0; |
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if (sb->sb_wptr) |
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sb->sb_datalen = size; |
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else |
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sb->sb_datalen = 0; |
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} |
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} else { |
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sb->sb_wptr = sb->sb_rptr = sb->sb_data = (char *)malloc(size); |
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sb->sb_cc = 0; |
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if (sb->sb_wptr) |
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sb->sb_datalen = size; |
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else |
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sb->sb_datalen = 0; |
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} |
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} |
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|
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/* |
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* Try and write() to the socket, whatever doesn't get written |
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* append to the buffer... for a host with a fast net connection, |
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* this prevents an unnecessary copy of the data |
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* (the socket is non-blocking, so we won't hang) |
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*/ |
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void |
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sbappend(so, m) |
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struct socket *so; |
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struct mbuf *m; |
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{ |
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int ret = 0; |
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|
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DEBUG_CALL("sbappend"); |
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DEBUG_ARG("so = %lx", (long)so); |
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DEBUG_ARG("m = %lx", (long)m); |
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DEBUG_ARG("m->m_len = %d", m->m_len); |
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|
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/* Shouldn't happen, but... e.g. foreign host closes connection */ |
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if (m->m_len <= 0) { |
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m_free(m); |
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return; |
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} |
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|
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/* |
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* If there is urgent data, call sosendoob |
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* if not all was sent, sowrite will take care of the rest |
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* (The rest of this function is just an optimisation) |
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*/ |
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if (so->so_urgc) { |
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sbappendsb(&so->so_rcv, m); |
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m_free(m); |
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sosendoob(so); |
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return; |
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} |
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|
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/* |
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* We only write if there's nothing in the buffer, |
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* ottherwise it'll arrive out of order, and hence corrupt |
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*/ |
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if (!so->so_rcv.sb_cc) |
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ret = send(so->s, m->m_data, m->m_len, 0); |
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|
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if (ret <= 0) { |
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/* |
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* Nothing was written |
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* It's possible that the socket has closed, but |
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* we don't need to check because if it has closed, |
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* it will be detected in the normal way by soread() |
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*/ |
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sbappendsb(&so->so_rcv, m); |
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} else if (ret != m->m_len) { |
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/* |
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* Something was written, but not everything.. |
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* sbappendsb the rest |
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*/ |
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m->m_len -= ret; |
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m->m_data += ret; |
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sbappendsb(&so->so_rcv, m); |
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} /* else */ |
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/* Whatever happened, we free the mbuf */ |
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m_free(m); |
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} |
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|
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/* |
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* Copy the data from m into sb |
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* The caller is responsible to make sure there's enough room |
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*/ |
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void |
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sbappendsb(sb, m) |
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struct sbuf *sb; |
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struct mbuf *m; |
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{ |
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int len, n, nn; |
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|
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len = m->m_len; |
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|
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if (sb->sb_wptr < sb->sb_rptr) { |
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n = sb->sb_rptr - sb->sb_wptr; |
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if (n > len) n = len; |
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memcpy(sb->sb_wptr, m->m_data, n); |
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} else { |
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/* Do the right edge first */ |
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n = sb->sb_data + sb->sb_datalen - sb->sb_wptr; |
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if (n > len) n = len; |
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memcpy(sb->sb_wptr, m->m_data, n); |
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len -= n; |
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if (len) { |
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/* Now the left edge */ |
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nn = sb->sb_rptr - sb->sb_data; |
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if (nn > len) nn = len; |
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memcpy(sb->sb_data,m->m_data+n,nn); |
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n += nn; |
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} |
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} |
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|
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sb->sb_cc += n; |
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sb->sb_wptr += n; |
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if (sb->sb_wptr >= sb->sb_data + sb->sb_datalen) |
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sb->sb_wptr -= sb->sb_datalen; |
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} |
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|
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/* |
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* Copy data from sbuf to a normal, straight buffer |
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* Don't update the sbuf rptr, this will be |
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* done in sbdrop when the data is acked |
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*/ |
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void |
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sbcopy(sb, off, len, to) |
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struct sbuf *sb; |
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int off; |
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int len; |
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char *to; |
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{ |
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char *from; |
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|
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from = sb->sb_rptr + off; |
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if (from >= sb->sb_data + sb->sb_datalen) |
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from -= sb->sb_datalen; |
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|
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if (from < sb->sb_wptr) { |
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if (len > sb->sb_cc) len = sb->sb_cc; |
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memcpy(to,from,len); |
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} else { |
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/* re-use off */ |
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off = (sb->sb_data + sb->sb_datalen) - from; |
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if (off > len) off = len; |
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memcpy(to,from,off); |
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len -= off; |
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if (len) |
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memcpy(to+off,sb->sb_data,len); |
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} |
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} |
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