src/slirp/sbuf.c

/*
 * Copyright (c) 1995 Danny Gasparovski.
 * 
 * Please read the file COPYRIGHT for the 
 * terms and conditions of the copyright.
 */

#include <stdlib.h>
#include <slirp.h>

/* Done as a macro in socket.h */
/* int
 * sbspace(struct sockbuff *sb) 
 * {
 *      return SB_DATALEN - sb->sb_cc;
 * }
 */

void
sbfree(sb)
        struct sbuf *sb;
{
        free(sb->sb_data);
}

void
sbdrop(sb, num)
        struct sbuf *sb;
        int num; 
{
        /* 
         * We can only drop how much we have
         * This should never succeed 
         */
        if(num > sb->sb_cc)
                num = sb->sb_cc;
        sb->sb_cc -= num;
        sb->sb_rptr += num;
        if(sb->sb_rptr >= sb->sb_data + sb->sb_datalen)
                sb->sb_rptr -= sb->sb_datalen;
   
}

void
sbreserve(sb, size)
        struct sbuf *sb;
        int size;
{
        if (sb->sb_data) {
                /* Already alloced, realloc if necessary */
                if (sb->sb_datalen != size) {
                        sb->sb_wptr = sb->sb_rptr = sb->sb_data = (char *)realloc(sb->sb_data, size);
                        sb->sb_cc = 0;
                        if (sb->sb_wptr)
                           sb->sb_datalen = size;
                        else
                           sb->sb_datalen = 0;
                }
        } else {
                sb->sb_wptr = sb->sb_rptr = sb->sb_data = (char *)malloc(size);
                sb->sb_cc = 0;
                if (sb->sb_wptr)
                   sb->sb_datalen = size;
                else
                   sb->sb_datalen = 0;
        }
}

/*
 * Try and write() to the socket, whatever doesn't get written
 * append to the buffer... for a host with a fast net connection,
 * this prevents an unnecessary copy of the data
 * (the socket is non-blocking, so we won't hang)
 */
void
sbappend(so, m)
        struct socket *so;
        struct mbuf *m;
{
        int ret = 0;
        
        DEBUG_CALL("sbappend");
        DEBUG_ARG("so = %lx", (long)so);
        DEBUG_ARG("m = %lx", (long)m);
        DEBUG_ARG("m->m_len = %d", m->m_len);
        
        /* Shouldn't happen, but...  e.g. foreign host closes connection */
        if (m->m_len <= 0) {
                m_free(m);
                return;
        }
        
        /*
         * If there is urgent data, call sosendoob
         * if not all was sent, sowrite will take care of the rest
         * (The rest of this function is just an optimisation)
         */
        if (so->so_urgc) {
                sbappendsb(&so->so_rcv, m);
                m_free(m);
                sosendoob(so);
                return;
        }
        
        /*
         * We only write if there's nothing in the buffer,
         * ottherwise it'll arrive out of order, and hence corrupt
         */
        if (!so->so_rcv.sb_cc)
           ret = send(so->s, m->m_data, m->m_len, 0);
        
        if (ret <= 0) {
                /* 
                 * Nothing was written
                 * It's possible that the socket has closed, but
                 * we don't need to check because if it has closed,
                 * it will be detected in the normal way by soread()
                 */
                sbappendsb(&so->so_rcv, m);
        } else if (ret != m->m_len) {
                /*
                 * Something was written, but not everything..
                 * sbappendsb the rest
                 */
                m->m_len -= ret;
                m->m_data += ret;
                sbappendsb(&so->so_rcv, m);
        } /* else */
        /* Whatever happened, we free the mbuf */
        m_free(m);
}

/*
 * Copy the data from m into sb
 * The caller is responsible to make sure there's enough room
 */
void
sbappendsb(sb, m)
         struct sbuf *sb;
         struct mbuf *m;
{
        int len, n,  nn;
        
        len = m->m_len;

        if (sb->sb_wptr < sb->sb_rptr) {
                n = sb->sb_rptr - sb->sb_wptr;
                if (n > len) n = len;
                memcpy(sb->sb_wptr, m->m_data, n);
        } else {
                /* Do the right edge first */
                n = sb->sb_data + sb->sb_datalen - sb->sb_wptr;
                if (n > len) n = len;
                memcpy(sb->sb_wptr, m->m_data, n);
                len -= n;
                if (len) {
                        /* Now the left edge */
                        nn = sb->sb_rptr - sb->sb_data;
                        if (nn > len) nn = len;
                        memcpy(sb->sb_data,m->m_data+n,nn);
                        n += nn;
                }
        }

        sb->sb_cc += n;
        sb->sb_wptr += n;
        if (sb->sb_wptr >= sb->sb_data + sb->sb_datalen)
                sb->sb_wptr -= sb->sb_datalen;
}

/*
 * Copy data from sbuf to a normal, straight buffer
 * Don't update the sbuf rptr, this will be
 * done in sbdrop when the data is acked
 */
void
sbcopy(sb, off, len, to)
        struct sbuf *sb;
        int off;
        int len;
        char *to;
{
        char *from;
        
        from = sb->sb_rptr + off;
        if (from >= sb->sb_data + sb->sb_datalen)
                from -= sb->sb_datalen;

        if (from < sb->sb_wptr) {
                if (len > sb->sb_cc) len = sb->sb_cc;
                memcpy(to,from,len);
        } else {
                /* re-use off */
                off = (sb->sb_data + sb->sb_datalen) - from;
                if (off > len) off = len;
                memcpy(to,from,off);
                len -= off;
                if (len)
                   memcpy(to+off,sb->sb_data,len);
        }
}
                
Revision:	1.2
Committed:	2007-01-22T14:48:40Z (17 years, 8 months ago) by asvitkine
Content type:	text/plain
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.1:	+1 -0 lines
Log Message:	fix compile warnings w/ slirp caused by not including stdlib
#	User	Rev	Content
1	gbeauche	1.1	/*
2			* Copyright (c) 1995 Danny Gasparovski.
3			*
4			* Please read the file COPYRIGHT for the
5			* terms and conditions of the copyright.
6			*/
7
8	asvitkine	1.2	#include <stdlib.h>
9	gbeauche	1.1	#include <slirp.h>
10
11			/* Done as a macro in socket.h */
12			/* int
13			* sbspace(struct sockbuff *sb)
14			* {
15			* return SB_DATALEN - sb->sb_cc;
16			* }
17			*/
18
19			void
20			sbfree(sb)
21			struct sbuf *sb;
22			{
23			free(sb->sb_data);
24			}
25
26			void
27			sbdrop(sb, num)
28			struct sbuf *sb;
29			int num;
30			{
31			/*
32			* We can only drop how much we have
33			* This should never succeed
34			*/
35			if(num > sb->sb_cc)
36			num = sb->sb_cc;
37			sb->sb_cc -= num;
38			sb->sb_rptr += num;
39			if(sb->sb_rptr >= sb->sb_data + sb->sb_datalen)
40			sb->sb_rptr -= sb->sb_datalen;
41
42			}
43
44			void
45			sbreserve(sb, size)
46			struct sbuf *sb;
47			int size;
48			{
49			if (sb->sb_data) {
50			/* Already alloced, realloc if necessary */
51			if (sb->sb_datalen != size) {
52			sb->sb_wptr = sb->sb_rptr = sb->sb_data = (char *)realloc(sb->sb_data, size);
53			sb->sb_cc = 0;
54			if (sb->sb_wptr)
55			sb->sb_datalen = size;
56			else
57			sb->sb_datalen = 0;
58			}
59			} else {
60			sb->sb_wptr = sb->sb_rptr = sb->sb_data = (char *)malloc(size);
61			sb->sb_cc = 0;
62			if (sb->sb_wptr)
63			sb->sb_datalen = size;
64			else
65			sb->sb_datalen = 0;
66			}
67			}
68
69			/*
70			* Try and write() to the socket, whatever doesn't get written
71			* append to the buffer... for a host with a fast net connection,
72			* this prevents an unnecessary copy of the data
73			* (the socket is non-blocking, so we won't hang)
74			*/
75			void
76			sbappend(so, m)
77			struct socket *so;
78			struct mbuf *m;
79			{
80			int ret = 0;
81
82			DEBUG_CALL("sbappend");
83			DEBUG_ARG("so = %lx", (long)so);
84			DEBUG_ARG("m = %lx", (long)m);
85			DEBUG_ARG("m->m_len = %d", m->m_len);
86
87			/* Shouldn't happen, but... e.g. foreign host closes connection */
88			if (m->m_len <= 0) {
89			m_free(m);
90			return;
91			}
92
93			/*
94			* If there is urgent data, call sosendoob
95			* if not all was sent, sowrite will take care of the rest
96			* (The rest of this function is just an optimisation)
97			*/
98			if (so->so_urgc) {
99			sbappendsb(&so->so_rcv, m);
100			m_free(m);
101			sosendoob(so);
102			return;
103			}
104
105			/*
106			* We only write if there's nothing in the buffer,
107			* ottherwise it'll arrive out of order, and hence corrupt
108			*/
109			if (!so->so_rcv.sb_cc)
110			ret = send(so->s, m->m_data, m->m_len, 0);
111
112			if (ret <= 0) {
113			/*
114			* Nothing was written
115			* It's possible that the socket has closed, but
116			* we don't need to check because if it has closed,
117			* it will be detected in the normal way by soread()
118			*/
119			sbappendsb(&so->so_rcv, m);
120			} else if (ret != m->m_len) {
121			/*
122			* Something was written, but not everything..
123			* sbappendsb the rest
124			*/
125			m->m_len -= ret;
126			m->m_data += ret;
127			sbappendsb(&so->so_rcv, m);
128			} /* else */
129			/* Whatever happened, we free the mbuf */
130			m_free(m);
131			}
132
133			/*
134			* Copy the data from m into sb
135			* The caller is responsible to make sure there's enough room
136			*/
137			void
138			sbappendsb(sb, m)
139			struct sbuf *sb;
140			struct mbuf *m;
141			{
142			int len, n, nn;
143
144			len = m->m_len;
145
146			if (sb->sb_wptr < sb->sb_rptr) {
147			n = sb->sb_rptr - sb->sb_wptr;
148			if (n > len) n = len;
149			memcpy(sb->sb_wptr, m->m_data, n);
150			} else {
151			/* Do the right edge first */
152			n = sb->sb_data + sb->sb_datalen - sb->sb_wptr;
153			if (n > len) n = len;
154			memcpy(sb->sb_wptr, m->m_data, n);
155			len -= n;
156			if (len) {
157			/* Now the left edge */
158			nn = sb->sb_rptr - sb->sb_data;
159			if (nn > len) nn = len;
160			memcpy(sb->sb_data,m->m_data+n,nn);
161			n += nn;
162			}
163			}
164
165			sb->sb_cc += n;
166			sb->sb_wptr += n;
167			if (sb->sb_wptr >= sb->sb_data + sb->sb_datalen)
168			sb->sb_wptr -= sb->sb_datalen;
169			}
170
171			/*
172			* Copy data from sbuf to a normal, straight buffer
173			* Don't update the sbuf rptr, this will be
174			* done in sbdrop when the data is acked
175			*/
176			void
177			sbcopy(sb, off, len, to)
178			struct sbuf *sb;
179			int off;
180			int len;
181			char *to;
182			{
183			char *from;
184
185			from = sb->sb_rptr + off;
186			if (from >= sb->sb_data + sb->sb_datalen)
187			from -= sb->sb_datalen;
188
189			if (from < sb->sb_wptr) {
190			if (len > sb->sb_cc) len = sb->sb_cc;
191			memcpy(to,from,len);
192			} else {
193			/* re-use off */
194			off = (sb->sb_data + sb->sb_datalen) - from;
195			if (off > len) off = len;
196			memcpy(to,from,off);
197			len -= off;
198			if (len)
199			memcpy(to+off,sb->sb_data,len);
200			}
201			}
202