Annotation of libwww/Library/src/HTBufWrt.c, revision 2.18
2.1 frystyk 1: /*
2: ** BUFFERED TRANSPORT WRITER STREAM
3: **
4: ** (c) COPYRIGHT MIT 1995.
5: ** Please first read the full copyright statement in the file COPYRIGH.
2.18 ! frystyk 6: ** @(#) $Id: HTBufWrt.c,v 2.17 1998/01/04 16:53:54 frystyk Exp $
2.1 frystyk 7: **
8: ** A buffered output stream. This stream lets you write characters to a
9: ** stream without causing a write every time. The data is first written
10: ** into a buffer. Data is written to the actual stream only when the
11: ** buffer is full, or when the stream is flushed.
12: */
13:
14: /* Library include files */
15: #include "sysdep.h"
16: #include "WWWUtil.h"
17: #include "WWWCore.h"
18: #include "HTNetMan.h"
19: #include "HTWriter.h"
2.6 frystyk 20: #include "HTTimer.h"
2.1 frystyk 21: #include "HTBufWrt.h" /* Implemented here */
22:
23: struct _HTOutputStream {
24: const HTOutputStreamClass * isa;
25: HTOutputStream * target; /* Target for outgoing data */
2.6 frystyk 26: HTHost * host;
2.15 frystyk 27:
28: int allocated; /* Allocated Buffer size */
29: int growby;
2.16 frystyk 30: int expo;
2.15 frystyk 31:
2.1 frystyk 32: char * read; /* Position in 'data' */
33: char * data; /* buffer */
2.6 frystyk 34:
2.7 frystyk 35: ms_t lastFlushTime; /* polar coordinates of the moon */
2.6 frystyk 36: HTTimer * timer;
2.1 frystyk 37: };
38:
39: #define PUTBLOCK(b,l) (*me->target->isa->put_block)(me->target,(b),(l))
40:
41: /* ------------------------------------------------------------------------- */
42:
2.11 frystyk 43: /*
44: ** This function is only called from either FlushEvent or HTBufferWriter_lazyFlush
45: ** which means that only the host object or timeout can cause a flush
46: */
2.1 frystyk 47: PRIVATE int HTBufferWriter_flush (HTOutputStream * me)
48: {
2.17 frystyk 49: int status = HT_OK;
2.11 frystyk 50: if (me && me->read > me->data) {
2.16 frystyk 51: me->lastFlushTime = HTGetTimeInMillis();
52: if ((status = PUTBLOCK(me->data, me->read - me->data))==HT_WOULD_BLOCK)
2.1 frystyk 53: return HT_WOULD_BLOCK;
54: me->read = me->data;
55: }
56: return status;
57: }
58:
2.9 eric 59: PRIVATE int FlushEvent (HTTimer * timer, void * param, HTEventType type)
2.6 frystyk 60: {
61: HTOutputStream * me = (HTOutputStream *) param;
62: if (timer != me->timer) HTDebugBreak();
2.17 frystyk 63: if (PROT_TRACE) HTTrace("Buffer...... Timeout flushing %p with timer %p\n", me, timer);
2.11 frystyk 64:
65: /*
66: ** We ignore the return code here which we shouldn't!!!
67: */
2.6 frystyk 68: HTBufferWriter_flush(me);
2.11 frystyk 69:
70: /*
71: ** Delete the timer
72: */
73: me->timer = NULL;
2.6 frystyk 74: return HT_OK;
75: }
76:
77: PRIVATE int HTBufferWriter_lazyFlush (HTOutputStream * me)
78: {
79: HTNet * net;
80: int delay;
81:
2.18 ! frystyk 82: if (me->read <= me->data) {
! 83: #if 0
! 84: fprintf(stderr, "nothing to flush\n");
! 85: #endif
2.6 frystyk 86: return HT_OK; /* nothing to flush */
2.18 ! frystyk 87: }
2.6 frystyk 88: /*
89: ** If we are allowed to delay the flush then set a timer with the
90: ** delay descibed by our delay variable. If we can't delay then flush
91: ** right away.
92: */
2.12 frystyk 93: delay = HTHost_findWriteDelay(me->host, me->lastFlushTime, me->read - me->data);
2.6 frystyk 94:
95: /*
96: ** Flush immediately
97: */
2.11 frystyk 98: if (!delay) {
99: int status;
2.17 frystyk 100: if (PROT_TRACE) HTTrace("Buffer...... Flushing %p\n", me);
2.11 frystyk 101: if ((status = HTBufferWriter_flush(me)) && me->timer) {
102: HTTimer_delete(me->timer);
103: me->timer = NULL;
104: }
105: return status;
106: }
2.6 frystyk 107:
108: /*
2.11 frystyk 109: ** Set a timer and tell the host we've done the write if
110: ** we have not already started a timer earlier.
2.6 frystyk 111: */
2.11 frystyk 112: if (!me->timer) {
2.14 frystyk 113: ms_t exp = HTGetTimeInMillis() + delay;
2.11 frystyk 114: net = HTHost_getWriteNet(me->host);
2.14 frystyk 115: me->timer = HTTimer_new(NULL, FlushEvent, me, exp, NO);
2.11 frystyk 116: HTHost_unregister(me->host, net, HTEvent_WRITE);
2.17 frystyk 117: if (PROT_TRACE) HTTrace("Buffer...... Waiting %p\n", me);
2.11 frystyk 118: }
2.6 frystyk 119: return HT_OK;
120: }
121:
2.1 frystyk 122: PRIVATE int HTBufferWriter_free (HTOutputStream * me)
123: {
2.11 frystyk 124: return HTBufferWriter_lazyFlush(me);
2.1 frystyk 125: }
126:
2.15 frystyk 127: PRIVATE BOOL HTBufferWriter_addBuffer(HTOutputStream * me, int addthis)
128: {
129: if (me) {
2.16 frystyk 130: me->allocated += (addthis - addthis%me->growby + (me->growby*me->expo));
2.17 frystyk 131: me->expo *= 2;
2.16 frystyk 132: if (PROT_TRACE) HTTrace("Buffer...... Increasing buffer to %d bytes\n", me->allocated);
2.15 frystyk 133: if (me->data) {
134: int size = me->read-me->data;
135: if ((me->data = (char *) HT_REALLOC(me->data, me->allocated)) == NULL)
136: HT_OUTOFMEM("HTBufferWriter_addBuffer");
137: me->read = me->data + size;
138: } else {
139: if ((me->data = (char *) HT_CALLOC(1, me->allocated)) == NULL)
140: HT_OUTOFMEM("HTBufferWriter_addBuffer");
141: me->read = me->data;
142: }
143: return YES;
144: }
145: return NO;
146: }
147:
2.1 frystyk 148: PRIVATE int HTBufferWriter_abort (HTOutputStream * me, HTList * e)
149: {
2.8 frystyk 150: if (PROT_TRACE) HTTrace("Buffer...... ABORTING...\n");
2.1 frystyk 151: if (me->target) (*me->target->isa->abort)(me->target, e);
2.8 frystyk 152: if (me->timer) {
153: HTTimer_delete(me->timer);
154: me->timer = NULL;
155: }
2.1 frystyk 156: return HT_ERROR;
157: }
158:
2.6 frystyk 159: PRIVATE int HTBufferWriter_write (HTOutputStream * me, const char * buf, int len)
2.1 frystyk 160: {
2.6 frystyk 161: HTNet * net = HTHost_getWriteNet(me->host);
2.1 frystyk 162: int status;
2.16 frystyk 163: while (1) {
164: int available = me->data + me->allocated - me->read;
165:
166: /* If we have enough buffer space */
167: if (len <= available) {
168: int size = 0;
169: memcpy(me->read, buf, len);
170: me->read += len;
2.15 frystyk 171:
2.16 frystyk 172: /* If we have accumulated enough data then flush */
173: if ((size = me->read - me->data) > me->growby) {
174: me->lastFlushTime = HTGetTimeInMillis();
175: status = PUTBLOCK(me->data, size);
176: if (status == HT_OK) {
177: HTNet_addBytesWritten(net, size);
178: me->read = me->data;
179: } else {
180: return (status == HT_WOULD_BLOCK) ? HT_OK : HT_ERROR;
181: }
182: }
183: return HT_OK;
184: } else {
185:
186: /* Fill the existing buffer (if not already) and flush */
187: if (available) {
188: memcpy(me->read, buf, available);
189: buf += available;
190: len -= available;
191: me->read += available;
192: }
193: me->lastFlushTime = HTGetTimeInMillis();
194: status = PUTBLOCK(me->data, me->allocated);
195: if (status == HT_OK) {
196: HTNet_addBytesWritten(net, me->allocated);
197: me->read = me->data;
198: } else if (status == HT_WOULD_BLOCK) {
199: HTBufferWriter_addBuffer(me, len);
200: memcpy(me->read, buf, len);
201: me->read += len;
202: return HT_OK;
203: }
204: }
2.15 frystyk 205: }
2.1 frystyk 206: }
207:
208: /* Character handling
209: ** ------------------
210: */
211: PRIVATE int HTBufferWriter_put_character (HTOutputStream * me, char c)
212: {
213: return HTBufferWriter_write(me, &c, 1);
214: }
215:
216: /* String handling
217: ** ---------------
218: **
219: ** Strings must be smaller than this buffer size.
220: */
221: PRIVATE int HTBufferWriter_put_string (HTOutputStream * me, const char * s)
222: {
223: return HTBufferWriter_write(me, s, (int) strlen(s));
224: }
225: /*
226: ** The difference between the close and the free method is that we don't
227: ** close the connection in the free method - we only call the free method
228: ** of the target stream. That way, we can keep the output stream as long
229: ** as the channel itself.
230: */
231: PRIVATE int HTBufferWriter_close (HTOutputStream * me)
232: {
233: if (me) {
234: if (me->target) (*me->target->isa->close)(me->target);
235: HT_FREE(me->data);
236: HT_FREE(me);
237: }
238: return HT_OK;
239: }
240:
241: PRIVATE const HTOutputStreamClass HTBufferWriter =
242: {
2.6 frystyk 243: "BufferedSocketWriter",
244: HTBufferWriter_lazyFlush,
2.1 frystyk 245: HTBufferWriter_free,
246: HTBufferWriter_abort,
247: HTBufferWriter_put_character,
248: HTBufferWriter_put_string,
249: HTBufferWriter_write,
250: HTBufferWriter_close
251: };
252:
2.6 frystyk 253: PUBLIC HTOutputStream * HTBufferWriter_new (HTHost * host, HTChannel * ch,
2.1 frystyk 254: void * param, int bufsize)
255: {
2.6 frystyk 256: if (host && ch) {
2.1 frystyk 257: HTOutputStream * me = HTChannel_output(ch);
2.6 frystyk 258: if (!me) {
259: HTOutputStream * me;
2.16 frystyk 260: int tcpbufsize = 0;
261:
262: #if defined(HAVE_GETSOCKOPT) && defined(SO_SNDBUF)
263: /*
264: ** Get the TCP socket buffer size
265: */
266: {
267: SOCKET sockfd = HTChannel_socket(ch);
268: int size = sizeof(int);
269: int status = getsockopt(sockfd, SOL_SOCKET, SO_SNDBUF,
270: (void *) &tcpbufsize, &size);
271: if (status == -1) {
272: if (PROT_TRACE)
273: HTTrace("Socket...... Could not get TCP send buffer size for socket %d\n", sockfd);
274: } else {
275: if (PROT_TRACE)
276: HTTrace("Socket...... TCP send buffer size is %d for socket %d\n", tcpbufsize, sockfd);
277: }
278: }
279: #endif
2.17 frystyk 280: if (bufsize <= 0) bufsize = tcpbufsize ? tcpbufsize : OUTPUT_BUFFER_SIZE;
2.6 frystyk 281: if ((me = (HTOutputStream *) HT_CALLOC(1, sizeof(HTOutputStream)))==NULL ||
2.1 frystyk 282: (me->data = (char *) HT_MALLOC(bufsize)) == NULL)
283: HT_OUTOFMEM("HTBufferWriter_new");
284: me->isa = &HTBufferWriter;
285: me->read = me->data;
2.15 frystyk 286: me->allocated = bufsize;
287: me->growby = bufsize;
2.16 frystyk 288: me->expo = 1;
2.6 frystyk 289: me->target = HTWriter_new(host, ch, param, 0);
290: me->host = host;
2.15 frystyk 291: return me;
2.6 frystyk 292: }
2.1 frystyk 293: }
294: return NULL;
295: }
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