Subversion Repositories planix.SVN

#include <u.h>
#include <libc.h>
#include <fcall.h>

int
read9pmsg(int fd, void *abuf, uint n)
{
        int m, len;
        uchar *buf;

        buf = abuf;

        /* read count */
        m = readn(fd, buf, BIT32SZ);
        if(m != BIT32SZ){
                if(m < 0)
                        return -1;
                return 0;
        }

        len = GBIT32(buf);
        if(len <= BIT32SZ || len > n){
                werrstr("bad length in 9P2000 message header");
                return -1;
        }
        len -= BIT32SZ;
        m = readn(fd, buf+BIT32SZ, len);
        if(m < len)
                return 0;
        return BIT32SZ+m;
}