File: libhttp.c

package info (click to toggle)
getstream 20070419-1
  • links: PTS
  • area: main
  • in suites: lenny
  • size: 308 kB
  • ctags: 658
  • sloc: ansic: 4,137; makefile: 58
file content (573 lines) | stat: -rw-r--r-- 12,481 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573

#include <sys/socket.h>
#include <sys/types.h>
#include <sys/time.h>
#include <event.h>
#include <unistd.h>
#include <fcntl.h>
#include <time.h>

#include <strings.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>

#include <glib/glist.h>

#include "libhttp.h"

//#define DEBUG
#ifdef DEBUG
#define Dprintf		printf
#else
#define Dprintf( a... )
#endif

int http_get_cmd(char *cmd) {
	if (strcasecmp("GET", cmd) == 0)
		return HC_CMD_GET;
	if (strcasecmp("POST", cmd) == 0)
		return HC_CMD_POST;
	if (strcasecmp("HEAD", cmd) == 0)
		return HC_CMD_HEAD;

	return HC_CMD_UNKNOWN;
}

/* Split line into string elements seperated by space or tab */
static int split_string_by_space(char *input, char **elem, int max) {
	int	no;
	char	*i=input;

	for(no=0;no<max;) {
		/* Skip space or tab */
		while(*i == ' ' || *i == '\t' || *i == '\r' || *i == '\n')
			*i++=0x0;
		if(*i == 0x0)
			break;
		/* Store pointer */
		elem[no++]=i;
		/* Skip non space */
		while(*i != ' ' && *i != '\t' && *i != 0x0)
			i++;
		/* End of String ? */
		if(*i == 0x0)
			break;
	}

	return no;
}

/*
 * Parse a string like HTTP/1.0 or HTTP/1.1 and return
 * the protocol and version
 *
 *
 * HP_UNKNOWN		- Unknown protocol
 * HP_HTTP		- Seems to be HTTP without/with broken/with unknown version
 * HP_HTTP10		- HTTP/1.0
 * HP_HTTP11		- HTTP/1.1
 *
 */
static int http_parse_proto(char *pstr) {
	char		*pver, *dotptr, *endptr;
	int		major, minor;

	/* Check if we are dealing with HTTP */
	if (strncasecmp(pstr, "HTTP", 4) != 0)
		return HP_UNKNOWN;

	pver=strchr(pstr, '/');
	if (!pver)
		return HP_HTTP;

	major=strtol(++pver, &dotptr, 10);

	/* 1.0 or 1.1 */
	if (*dotptr != '.')
		return HP_HTTP;

	minor=strtol(++dotptr, &endptr, 10);

	/* String should end after [major].[minor] */
	if (*endptr != 0x0)
		return HP_HTTP;

	Dprintf("%s: major %d minor %d\n", __FUNCTION__, major, minor);

	if (major == 1 && minor == 0)
		return HP_HTTP10;
	if (major == 1 && minor == 1)
		return HP_HTTP11;

	return HP_HTTP;
}

/*
 * Read the first line - PUT/GET/POST etc ...
 *
 * GET <url> HTTP/<version>
 *
 */
static int http_parse_command_url(struct http_connection *hc, struct evbuffer *input) {
	char	*p=(char *) EVBUFFER_DATA(input);
	char	*elem[10];
	int	no;

	no=split_string_by_space(p, elem, 10);

	/* Need "CMD URL PROTO/VERSION" which makes it 3 parms */
	if (no != 3)
		return 0;

	if ((hc->cmd=http_get_cmd(elem[0])) == HC_CMD_UNKNOWN)
		return 0;

	hc->url=strdup(elem[1]);
	hc->proto=http_parse_proto(elem[2]);

	if (hc->proto == HP_HTTP11)
		hc->keepalive=1;
	else
		hc->keepalive=0;

	return 1;
}

static int http_parse_attrib(struct http_connection *hc, struct evbuffer *input) {
	char	*p=(char *) EVBUFFER_DATA(input);
	struct	http_attrib	*ha;
	char	*token, *value;

	token=p;

	while(*p != ':' && *p != ' ' && *p != 0x0)
		p++;

	/* Did we find the colon as delimiter ?
	 * If not something went really wrong - terminate the connection
	 */
	if (*p == ':')
		*p++=0x0;
	else
		return 0;

	while(*p == ' ' || *p == '\t')
		p++;

	value=p;

	ha=malloc(sizeof(struct http_attrib));
	ha->token=strdup(token);
	ha->value=strdup(value);

	hc->attrib=g_list_append(hc->attrib, ha);

	Dprintf("%s: %s %s\n", __FUNCTION__, token, value);

	return 1;
}

/*
 * HTTP/1.1 404 Not Found
 * Date: Wed, 17 May 2006 17:33:00 GMT
 * Server: Apache/2.0.54 (Debian GNU/Linux)
 * Content-Length: 310
 * Connection: close
 * Content-Type: text/html; charset=iso-8859-1
 *
 */
static char *http_static_msg_404 =
"<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\"> \
<html><head> \
<title>404 Not Found</title> \
</head><body> \
<h1>404 Not Found</h1> \
</body> \
</html>";

int http_url_handler_404(struct http_connection *hc, int cbtype, void *arg) {
	int		err;

	Dprintf("%s: cbtype %d\n", __FUNCTION__, cbtype);

	/* Answer with 404 page on QUERY */
	if (cbtype == HCB_QUERY) {
		err=http_return_simple(hc,
				"404 Not found",
				"text/html",
				http_static_msg_404,
				strlen(http_static_msg_404));
		return 1;
	}

	/*
	 * Drop connection if socket gets writeable again
	 * or we have an error
	 */
	http_request_end(hc);

	return 1;
}


size_t http_get_queue(struct http_connection *hc) {
	return EVBUFFER_LENGTH(hc->bev->output);
}

/*
 * Function to return an http chunk with previous unknown size. HTTP/1.1 allows
 * for chunked transfers which HTTP/1.0 doesnt know about. There is no legal way
 * to do this so we hope our best.
 *
 */
int http_return_stream(struct http_connection *hc, void *data, size_t datalen) {
	struct evbuffer *evb;

	evb=evbuffer_new();

	/* We are chunked and done sending - end session */
	if (!data) {
		/* Chunked transfer - send a 0 chunk */
		if (hc->proto == HP_HTTP11) {
			evbuffer_add_printf(evb,"0\r\n\r\n");
			bufferevent_write_buffer(hc->bev, evb);
		}
		evbuffer_free(evb);
		hc->status=HC_STATUS_END;
		return 1;
	}

	/* In case of Transfer-Encoding: chunked send a chunk - otherwise just data */
	if (hc->proto == HP_HTTP11) {
		evbuffer_add_printf(evb,"%x\r\n", datalen);
		evbuffer_add(evb, data, datalen);
		evbuffer_add_printf(evb, "\r\n");
	} else {
		evbuffer_add(evb, data, datalen);
	}

	bufferevent_write_buffer(hc->bev, evb);

	Dprintf("%s: output buffer len %d\n", __FUNCTION__,
			EVBUFFER_LENGTH(hc->bev->output));

	evbuffer_free(evb);
	return 1;
}

int http_header_add(struct http_connection *hc, char *fmt, ...) {
	va_list ap;
	va_start(ap, fmt);
	hc->hsize+=vsprintf(&hc->hdr[hc->hsize], fmt, ap);
	hc->hdr[hc->hsize++]=0x0d;
	hc->hdr[hc->hsize++]=0x0a;
	hc->hdr[hc->hsize]=0x00;
	va_end(ap);
	return 0;
}

int http_header_end(struct http_connection *hc) {
	if (hc->keepalive)
		http_header_add(hc, "Connection: keep-alive");
	else
		http_header_add(hc, "Connection: close");

	hc->hsize+=sprintf(&hc->hdr[hc->hsize], "\r\n");
	bufferevent_write(hc->bev, hc->hdr, hc->hsize);
	hc->hsize=0;
	return 0;
}

int http_header_clength(struct http_connection *hc, ssize_t length) {
	if (length >= 0)
		http_header_add(hc, "Content-Length: %d", length);
	else {
		if (hc->proto == HP_HTTP11)
			http_header_add(hc, "Transfer-Encoding: chunked");
	}
	return 0;
}

int http_header_nocache(struct http_connection *hc) {
	http_header_add(hc, "Pragma: no-cache");
	http_header_add(hc, "Cache-Control: no-cache");
	return 0;
}

int http_header_start(struct http_connection *hc, char *result, char *type) {
	struct tm	*tm;
	time_t		t;

	/* Wed, 17 May 2006 17:33:00 GMT */
	t=time(NULL);
	tm=gmtime(&t);

	hc->hsize=0;
	hc->hsize+=sprintf(&hc->hdr[hc->hsize],
			"HTTP/1.1 %s\r\n", result);
	hc->hsize+=sprintf(&hc->hdr[hc->hsize],
			"Date: ");
	hc->hsize+=strftime(&hc->hdr[hc->hsize],
			MAX_HEADER_SIZE-hc->hsize,
			"%a, %d %b %Y %H:%M:%S %Z\r\n", tm);

	http_header_add(hc, "Content-Type: %s", type);

	return 0;
}

/*
 * Send a simple request answer:
 * Content-Length: is set - No chunked, partial transfer,
 * After requests gets answered - connection will be closed
 *
 */
int http_return_simple(struct http_connection *hc, char *result,
		char *type, void *data, size_t datalen) {

	http_header_start(hc, result, type);
	http_header_clength(hc, datalen);
	http_header_end(hc);

	bufferevent_write(hc->bev, data, datalen);

	hc->status=HC_STATUS_END;
	return 1;
}

static int http_process_query(struct http_connection *hc) {
	struct http_url *hu;

	/*
	 * FIXME Need to parse url to parameters, unescaping
	 * characters etc ...
	 *
	 */
	hu=g_hash_table_lookup(hc->server->urls, hc->url);

	Dprintf("%s: hu %p\n", __FUNCTION__, hu);

	if (hu) {
		hc->url_handler=hu->cb;
		return hc->url_handler(hc, HCB_QUERY, hu->arg);
	}

	return hc->url_handler(hc, HCB_QUERY, NULL);
}

static int http_read_head(struct http_connection *hc, struct bufferevent *bev) {
	struct evbuffer	*input = EVBUFFER_INPUT(bev);
	u_char		*eol, *p;
	int		err, drainlen;

	while((eol=evbuffer_find(input, (u_char *) "\n", 1)) != NULL) {

		/* get begin of line */
		p=EVBUFFER_DATA(input);

		/* Line length */
		drainlen=eol-p+1;

		/*
		 * Remove \n and if exists the \r
		 * FIXME Is this robust enough ?
		 */
		*eol=0x0;
		if (eol > p && *(eol-1) == '\r')
			*(--eol) = 0x0;

		if (!hc->url) {
			/* Did we have the first line with command and url ? */
			err=http_parse_command_url(hc, input);
		} else if (eol == p) {
			err=http_process_query(hc);
		} else {
			err=http_parse_attrib(hc, input);
		}

		/* tell buffer to remove leading bytes */
		evbuffer_drain(input, drainlen);

		if (!err)
			return 0;
	}

	return 1;
}

/*
 * Free Request based resources from the http_connection
 *
 */
static void http_request_free(struct http_connection *hc) {
	GList			*item;
	struct http_attrib	*ha;

	if (hc->url)
		free(hc->url);
	hc->url=NULL;

	/* Free http attributes */
	while((item=g_list_first(hc->attrib))) {
		hc->attrib=g_list_remove_link(hc->attrib, item);

		ha=item->data;
		free(ha->token);
		free(ha->value);
		free(ha);

		g_list_free(item);
	}
}

/*
 * Drop the connection in case of error of non keepalive
 */
void http_drop_connection(struct http_connection *hc) {
	struct http_server	*hs=hc->server;

	http_request_free(hc);

	Dprintf("%s:%d\n", __FUNCTION__, __LINE__);
	hs->conn=g_list_remove(hs->conn, hc);

	bufferevent_disable(hc->bev, EV_READ|EV_WRITE);
	bufferevent_free(hc->bev);

	close(hc->fd);
}

/*
 * Application signals http request end - either
 * drop the connection or simply free the request
 * resources.
 *
 */
void http_request_end(struct http_connection *hc) {
	if (!hc->keepalive) {
		http_drop_connection(hc);
	} else {
		http_request_free(hc);
		hc->status=HC_STATUS_HEAD;
		hc->url_handler=&http_url_handler_404;
		hc->hsize=0;
	}
}

/*
 * Callback handler for EV_READ of the client connection. If data
 * arrives for our handler
 */
static void http_cb_read(struct bufferevent *bev, void *arg) {
	struct http_connection	*hc=arg;
	Dprintf("%s:%d\n", __FUNCTION__, __LINE__);
	switch(hc->status) {
		case(HC_STATUS_END):
			hc->url_handler(hc, HCB_END, hc->arg);
			break;
		case(HC_STATUS_HEAD):
			if (!http_read_head(hc, bev))
				http_drop_connection(hc);
			break;
		case(HC_STATUS_BODY):
			hc->url_handler(hc, HCB_READ, hc->arg);
			break;
	}
}

static void http_cb_write(struct bufferevent *bev, void *arg) {
	struct http_connection	*hc=arg;
	Dprintf("%s:%d\n", __FUNCTION__, __LINE__);

	if (hc->status != HC_STATUS_END)
		hc->url_handler(hc, HCB_WRITE, hc->arg);

	if (hc->status == HC_STATUS_END)
		hc->url_handler(hc, HCB_END, hc->arg);
}

static void http_cb_error(struct bufferevent *bev, short what, void *arg) {
	struct http_connection	*hc=arg;
	Dprintf("%s:%d\n", __FUNCTION__, __LINE__);
	hc->url_handler(hc, HCB_ERROR, hc->arg);
}

static void http_connect(int fd, short ev, void *arg) {
	struct http_server	*hs=arg;
	struct http_connection	*hc;
	struct sockaddr_in	sin;
	socklen_t		slen=sizeof(struct sockaddr_in);
	int			nfd;
	unsigned long		flags;

	nfd=accept(fd, (struct sockaddr *) &sin, &slen);

	if (nfd < 0)
		return;

	Dprintf("%s:%d New connection\n", __FUNCTION__, __LINE__);

	/* Set new socket O_NONBLOCK */
	flags=fcntl(nfd, F_GETFL);
	fcntl(nfd, F_SETFL, flags | O_NONBLOCK);

	hc=calloc(1, sizeof(struct http_connection));
	hc->fd=nfd;
	hc->server=hs;
	hc->status=HC_STATUS_HEAD;
	hc->cid=hs->cid++;

	/* Copy remote endpoint sockaddr to http_connection structure */
	memcpy(&hc->sin, &sin, sizeof(struct sockaddr_in));

	hc->bev=bufferevent_new(hc->fd, http_cb_read, http_cb_write, http_cb_error, hc);
	bufferevent_enable(hc->bev, EV_READ);

	hc->url_handler=&http_url_handler_404;

	hs->conn=g_list_append(hs->conn, hc);
}

int http_register_url(struct http_server *hs, struct http_url *hu) {
	while(hu->url) {
		g_hash_table_insert(hs->urls, hu->url, hu);
		hu++;
	}
	return 1;
}

struct http_server *http_init(int port) {
	struct http_server	*hs;
	unsigned long		flags;
	int			one=1;

	hs=calloc(1, sizeof(struct http_server));
	hs->port=port;
	hs->urls=g_hash_table_new(g_str_hash, g_str_equal);

	hs->fd=socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);

	setsockopt(hs->fd, SOL_SOCKET, SO_REUSEADDR,
			(void *) &one, sizeof(int));

	hs->sin.sin_family=AF_INET;
	hs->sin.sin_port=htons(port);
	hs->sin.sin_addr.s_addr=INADDR_ANY;

	if (bind(hs->fd, (struct sockaddr *) &hs->sin,
				sizeof(struct sockaddr_in)))
		return NULL;

	if (listen(hs->fd, 3))
		return NULL;

	flags=fcntl(hs->fd, F_GETFL);
	fcntl(hs->fd, F_GETFL, flags | O_NONBLOCK);

	event_set(&hs->ev, hs->fd, EV_READ|EV_PERSIST, http_connect, (void *) hs);
	event_add(&hs->ev, NULL);

	return hs;
}