tinywebd
view src/tinyweb.c @ 7:5ec50ca0d071
separated the server code
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Fri, 17 Apr 2015 11:45:08 +0300 |
| parents | |
| children | 121b991ccc1d |
line source
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4 #include <ctype.h>
5 #include <errno.h>
6 #include <unistd.h>
7 #include <fcntl.h>
8 #include <sys/stat.h>
9 #include <sys/select.h>
10 #include <sys/mman.h>
11 #include <sys/types.h>
12 #include <sys/socket.h>
13 #include <arpa/inet.h>
14 #include "tinyweb.h"
15 #include "http.h"
16 #include "mime.h"
17 #include "logger.h"
19 /* HTTP version */
20 #define HTTP_VER_MAJOR 1
21 #define HTTP_VER_MINOR 1
22 #define HTTP_VER_STR "1.1"
24 /* maximum request length: 64mb */
25 #define MAX_REQ_LENGTH (65536 * 1024)
27 struct client {
28 int s;
29 char *rcvbuf;
30 int bufsz;
31 struct client *next;
32 };
34 static int accept_conn(int lis);
35 static void close_conn(struct client *c);
36 static int handle_client(struct client *c);
37 static int do_get(struct client *c, const char *uri, int with_body);
38 static void respond_error(struct client *c, int errcode);
40 static int lis = -1;
41 static int maxfd;
42 static int port = 8080;
43 static struct client *clist;
44 static int num_clients;
46 static const char *indexfiles[] = {
47 "index.cgi",
48 "index.html",
49 "index.htm",
50 0
51 };
53 void tw_set_port(int p)
54 {
55 port = p;
56 }
58 int tw_set_root(const char *path)
59 {
60 return chdir(path);
61 }
63 int tw_set_logfile(const char *fname)
64 {
65 return set_log_file(fname);
66 }
68 int tw_start(void)
69 {
70 int s;
71 struct sockaddr_in sa;
73 logmsg("starting server ...\n");
75 if(lis != -1) {
76 logmsg("can't start tinyweb server: already running!\n");
77 return -1;
78 }
80 if((s = socket(PF_INET, SOCK_STREAM, 0)) == -1) {
81 logmsg("failed to create listening socket: %s\n", strerror(errno));
82 return -1;
83 }
84 fcntl(s, F_SETFL, fcntl(s, F_GETFL) | O_NONBLOCK);
86 memset(&sa, 0, sizeof sa);
87 sa.sin_family = AF_INET;
88 sa.sin_addr.s_addr = INADDR_ANY;
89 sa.sin_port = htons(port);
91 if(bind(s, (struct sockaddr*)&sa, sizeof sa) == -1) {
92 logmsg("failed to bind socket to port %d: %s\n", port, strerror(errno));
93 return -1;
94 }
95 listen(s, 16);
97 lis = s;
98 return s;
99 }
101 int tw_stop(void)
102 {
103 if(lis == -1) {
104 return -1;
105 }
107 logmsg("stopping server...\n");
109 close(lis);
110 lis = -1;
112 while(clist) {
113 struct client *c = clist;
114 clist = clist->next;
115 close_conn(c);
116 free(c);
117 }
118 clist = 0;
120 return 0;
121 }
123 int tw_get_sockets(int *socks)
124 {
125 struct client *c, dummy;
127 if(!socks) {
128 /* just return the count */
129 return num_clients + 1; /* +1 for the listening socket */
130 }
132 /* first cleanup the clients marked for removal */
133 dummy.next = clist;
134 c = &dummy;
136 while(c->next) {
137 struct client *n = c->next;
139 if(n->s == -1) {
140 /* marked for removal */
141 c->next = n->next;
142 free(n);
143 --num_clients;
144 } else {
145 c = c->next;
146 }
147 }
148 clist = dummy.next;
150 /* go through the client list and populate the array */
151 maxfd = lis;
152 *socks++ = lis;
154 c = clist;
155 while(c) {
156 *socks++ = c->s;
157 if(c->s > maxfd) {
158 maxfd = c->s;
159 }
160 c = c->next;
161 }
162 return num_clients + 1; /* +1 for the listening socket */
163 }
165 int tw_get_maxfd(void)
166 {
167 return maxfd;
168 }
170 int tw_handle_socket(int s)
171 {
172 struct client *c;
174 if(s == lis) {
175 return accept_conn(s);
176 }
178 /* find which client corresponds to this socket */
179 c = clist;
180 while(c) {
181 if(c->s == s) {
182 return handle_client(c);
183 }
184 c = c->next;
185 }
187 logmsg("socket %d doesn't correspond to any client\n");
188 return -1;
189 }
191 static int accept_conn(int lis)
192 {
193 int s;
194 struct client *c;
195 struct sockaddr_in addr;
196 socklen_t addr_sz = sizeof addr;
198 if((s = accept(lis, (struct sockaddr*)&addr, &addr_sz)) == -1) {
199 logmsg("failed to accept incoming connection: %s\n", strerror(errno));
200 return -1;
201 }
202 fcntl(s, F_SETFL, fcntl(s, F_GETFL) | O_NONBLOCK);
204 if(!(c = malloc(sizeof *c))) {
205 logmsg("failed to allocate memory while accepting connection: %s\n", strerror(errno));
206 return -1;
207 }
208 c->s = s;
209 c->rcvbuf = 0;
210 c->bufsz = 0;
211 c->next = clist;
212 clist = c;
213 return 0;
214 }
216 static void close_conn(struct client *c)
217 {
218 close(c->s);
219 c->s = -1; /* mark it for removal */
220 free(c->rcvbuf);
221 c->rcvbuf = 0;
222 }
224 static int handle_client(struct client *c)
225 {
226 struct http_req_header hdr;
227 static char buf[2048];
228 int rdsz, status;
230 while((rdsz = recv(c->s, buf, sizeof buf, 0)) > 0) {
231 char *newbuf;
232 int newsz = c->bufsz + rdsz;
233 if(newsz > MAX_REQ_LENGTH) {
234 respond_error(c, 413);
235 return -1;
236 }
238 if(!(newbuf = realloc(c->rcvbuf, newsz + 1))) {
239 logmsg("failed to allocate %d byte buffer\n", newsz);
240 respond_error(c, 503);
241 return -1;
242 }
244 memcpy(newbuf + c->bufsz, buf, rdsz);
245 newbuf[newsz] = 0;
247 c->rcvbuf = newbuf;
248 c->bufsz = newsz;
249 }
251 if((status = http_parse_request(&hdr, c->rcvbuf, c->bufsz)) != HTTP_HDR_OK) {
252 http_log_request(&hdr);
253 switch(status) {
254 case HTTP_HDR_INVALID:
255 respond_error(c, 400);
256 return -1;
258 case HTTP_HDR_NOMEM:
259 respond_error(c, 503);
260 return -1;
262 case HTTP_HDR_PARTIAL:
263 return 0; /* partial header, continue reading */
264 }
265 }
266 http_log_request(&hdr);
268 /* we only support GET and HEAD at this point, so freak out on anything else */
269 switch(hdr.method) {
270 case HTTP_GET:
271 if(do_get(c, hdr.uri, 1) == -1) {
272 return -1;
273 }
274 break;
276 case HTTP_HEAD:
277 if(do_get(c, hdr.uri, 0) == -1) {
278 return -1;
279 }
280 break;
282 default:
283 respond_error(c, 501);
284 return -1;
285 }
287 close_conn(c);
288 return 0;
289 }
291 static int do_get(struct client *c, const char *uri, int with_body)
292 {
293 const char *ptr;
294 struct http_resp_header resp;
296 if((ptr = strstr(uri, "://"))) {
297 uri = ptr + 3;
298 }
300 /* skip the host part and the first slash if it exists */
301 if((ptr = strchr(uri, '/'))) {
302 uri = ptr + 1;
303 }
305 if(*uri) {
306 struct stat st;
307 char *path = 0;
308 char *rsphdr;
309 const char *type;
310 int fd, rspsize;
312 if(stat(uri, &st) == -1) {
313 respond_error(c, 404);
314 return -1;
315 }
317 if(S_ISDIR(st.st_mode)) {
318 int i;
319 path = alloca(strlen(uri) + 64);
321 for(i=0; indexfiles[i]; i++) {
322 sprintf(path, "%s/%s", uri, indexfiles[i]);
323 if(stat(path, &st) == 0 && !S_ISDIR(st.st_mode)) {
324 break;
325 }
326 }
328 if(indexfiles[i] == 0) {
329 respond_error(c, 404);
330 return -1;
331 }
332 } else {
333 path = (char*)uri;
334 }
336 if((fd = open(path, O_RDONLY)) == -1) {
337 respond_error(c, 403);
338 return -1;
339 }
341 /* construct response header */
342 http_init_resp(&resp);
343 http_add_resp_field(&resp, "Content-Length: %d", st.st_size);
344 if((type = mime_type(path))) {
345 http_add_resp_field(&resp, "Content-Type: %s", type);
346 }
348 rspsize = http_serialize_resp(&resp, 0);
349 rsphdr = alloca(rspsize);
350 http_serialize_resp(&resp, rsphdr);
352 if(with_body) {
353 int cont_left = st.st_size;
354 char *cont = mmap(0, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
355 if(cont == (void*)-1) {
356 respond_error(c, 503);
357 close(fd);
358 return -1;
359 }
360 ptr = cont;
362 send(c->s, rsphdr, rspsize, 0);
363 while(cont_left > 0) {
364 int sz = cont_left < 4096 ? cont_left : 4096;
365 send(c->s, ptr, sz, 0);
366 ptr += sz;
367 }
369 munmap(cont, st.st_size);
370 } else {
371 send(c->s, rsphdr, rspsize, 0);
372 }
374 close(fd);
375 }
376 return 0;
377 }
379 static void respond_error(struct client *c, int errcode)
380 {
381 char buf[512];
383 sprintf(buf, "HTTP/" HTTP_VER_STR " %d %s\r\n\r\n", errcode, http_strmsg(errcode));
385 send(c->s, buf, strlen(buf), 0);
386 close_conn(c);
387 }