1 #include "a.h"
2 
3 static char*
4 haveheader(char *buf, int n)
5 {
6 	int i;
7 
8 	for(i=0; i<n; i++){
9 		if(buf[i] == '\n'){
10 			if(i+2 < n && buf[i+1] == '\r' && buf[i+2] == '\n')
11 				return buf+i+3;
12 			if(i+1 < n && buf[i+1] == '\n')
13 				return buf+i+2;
14 		}
15 	}
16 	return 0;
17 }
18 
19 static int
20 parseheader(char *buf, int n, HTTPHeader *hdr)
21 {
22 	int nline;
23 	char *data, *ebuf, *p, *q, *next;
24 	
25 	memset(hdr, 0, sizeof *hdr);
26 	ebuf = buf+n;
27 	data = haveheader(buf, n);
28 	if(data == nil)
29 		return -1;
30 
31 	data[-1] = 0;
32 	if(data[-2] == '\r')
33 		data[-2] = 0;
34 	if(chattyhttp > 1){
35 		fprint(2, "--HTTP Response Header:\n");
36 		fprint(2, "%s\n", buf);
37 		fprint(2, "--\n");
38 	}
39 	nline = 0;
40 	for(p=buf; *p; p=next, nline++){
41 		q = strchr(p, '\n');
42 		if(q){
43 			next = q+1;
44 			*q = 0;
45 			if(q > p && q[-1] == '\r')
46 				q[-1] = 0;
47 		}else
48 			next = p+strlen(p);
49 		if(nline == 0){
50 			if(memcmp(p, "HTTP/", 5) != 0){
51 				werrstr("invalid HTTP version: %.10s", p);
52 				return -1;
53 			}
54 			q = strchr(p, ' ');
55 			if(q == nil){
56 				werrstr("invalid HTTP version");
57 				return -1;
58 			}
59 			*q++ = 0;
60 			strncpy(hdr->proto, p, sizeof hdr->proto);
61 			hdr->proto[sizeof hdr->proto-1] = 0;
62 			while(*q == ' ')
63 				q++;
64 			if(*q < '0' || '9' < *q){
65 				werrstr("invalid HTTP response code");
66 				return -1;
67 			}
68 			p = q;
69 			q = strchr(p, ' ');
70 			if(q == nil)
71 				q = p+strlen(p);
72 			else
73 				*q++ = 0;
74 			hdr->code = strtol(p, &p, 10);
75 			if(*p != 0)
76 				return -1;
77 			while(*q == ' ')
78 				q++;
79 			strncpy(hdr->codedesc, q, sizeof hdr->codedesc);
80 			hdr->codedesc[sizeof hdr->codedesc-1] = 0;
81 			continue;				
82 		}
83 		q = strchr(p, ':');
84 		if(q == nil)
85 			continue;
86 		*q++ = 0;
87 		while(*q != 0 && (*q == ' ' || *q == '\t'))
88 			q++;
89 		if(cistrcmp(p, "Content-Type") == 0){
90 			strncpy(hdr->contenttype, q, sizeof hdr->contenttype);
91 			hdr->contenttype[sizeof hdr->contenttype-1] = 0;
92 			continue;
93 		}
94 		if(cistrcmp(p, "Content-Length") == 0 && '0' <= *q && *q <= '9'){
95 			hdr->contentlength = strtoll(q, 0, 10);
96 			continue;
97 		}
98 	}
99 	if(nline < 1){
100 		werrstr("no header");
101 		return -1;
102 	}
103 
104 	memmove(buf, data, ebuf - data);
105 	return ebuf - data;
106 } 
107 
108 static char*
109 genhttp(Protocol *proto, char *host, char *req, HTTPHeader *hdr, int wfd, int rfd, vlong rtotal)
110 {
111 	int n, m, total, want;
112 	char buf[8192], *data;
113 	Pfd *fd;
114 
115 	if(chattyhttp > 1){
116 		fprint(2, "--HTTP Request:\n");
117 		fprint(2, "%s", req);
118 		fprint(2, "--\n");
119 	}
120 	fd = proto->connect(host);
121 	if(fd == nil){
122 		if(chattyhttp > 0)
123 			fprint(2, "connect %s: %r\n", host);
124 		return nil;
125 	}
126 
127 	n = strlen(req);
128 	if(proto->write(fd, req, n) != n){
129 		if(chattyhttp > 0)
130 			fprint(2, "write %s: %r\n", host);
131 		proto->close(fd);
132 		return nil;
133 	}
134 	
135 	if(rfd >= 0){
136 		while(rtotal > 0){
137 			m = sizeof buf;
138 			if(m > rtotal)
139 				m = rtotal;
140 			if((n = read(rfd, buf, m)) <= 0){
141 				fprint(2, "read: missing data\n");
142 				proto->close(fd);
143 				return nil;
144 			}
145 			if(proto->write(fd, buf, n) != n){
146 				fprint(2, "write data: %r\n");
147 				proto->close(fd);
148 				return nil;
149 			}
150 			rtotal -= n;
151 		}
152 	}
153 
154 	total = 0;
155 	while(!haveheader(buf, total)){
156 		n = proto->read(fd, buf+total, sizeof buf-total);
157 		if(n <= 0){
158 			if(chattyhttp > 0)
159 				fprint(2, "read missing header\n");
160 			proto->close(fd);
161 			return nil;
162 		}
163 		total += n;
164 	}
165 
166 	n = parseheader(buf, total, hdr);
167 	if(n < 0){
168 		fprint(2, "failed response parse: %r\n");
169 		proto->close(fd);
170 		return nil;
171 	}
172 	if(hdr->contentlength >= MaxResponse){
173 		werrstr("response too long");
174 		proto->close(fd);
175 		return nil;
176 	}
177 	if(hdr->contentlength >= 0 && n > hdr->contentlength)
178 		n = hdr->contentlength;
179 	want = sizeof buf;
180 	data = nil;
181 	total = 0;
182 	goto didread;
183 
184 	while(want > 0 && (n = proto->read(fd, buf, want)) > 0){
185 	didread:
186 		if(wfd >= 0){
187 			if(writen(wfd, buf, n) < 0){
188 				proto->close(fd);
189 				werrstr("write error");
190 				return nil;
191 			}
192 		}else{
193 			data = erealloc(data, total+n);
194 			memmove(data+total, buf, n);
195 		}
196 		total += n;
197 		if(total > MaxResponse){
198 			proto->close(fd);
199 			werrstr("response too long");
200 			return nil;
201 		}
202 		if(hdr->contentlength >= 0 && total + want > hdr->contentlength)
203 			want = hdr->contentlength - total;
204 	}
205 	proto->close(fd);
206 
207 	if(hdr->contentlength >= 0 && total != hdr->contentlength){
208 		werrstr("got wrong content size %d %d", total, hdr->contentlength);
209 		return nil;
210 	}
211 	hdr->contentlength = total;
212 	if(wfd >= 0)
213 		return (void*)1;
214 	else{
215 		data = erealloc(data, total+1);
216 		data[total] = 0;
217 	}
218 	return data;
219 }
220 
221 char*
222 httpreq(Protocol *proto, char *host, char *req, HTTPHeader *hdr, int rfd, vlong rlength)
223 {
224 	return genhttp(proto, host, req, hdr, -1, rfd, rlength);
225 }
226 
227 int
228 httptofile(Protocol *proto, char *host, char *req, HTTPHeader *hdr, int fd)
229 {
230 	if(fd < 0){
231 		werrstr("bad fd");
232 		return -1;
233 	}
234 	if(genhttp(proto, host, req, hdr, fd, -1, 0) == nil)
235 		return -1;
236 	return 0;
237 }