Merge branch 'ml/encode-header-refactor' into next
[git] / http.c
1 #include "http.h"
2 #include "pack.h"
3 #include "sideband.h"
4
5 int data_received;
6 int active_requests;
7 int http_is_verbose;
8 size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
9
10 #if LIBCURL_VERSION_NUM >= 0x070a06
11 #define LIBCURL_CAN_HANDLE_AUTH_ANY
12 #endif
13
14 static int min_curl_sessions = 1;
15 static int curl_session_count;
16 #ifdef USE_CURL_MULTI
17 static int max_requests = -1;
18 static CURLM *curlm;
19 #endif
20 #ifndef NO_CURL_EASY_DUPHANDLE
21 static CURL *curl_default;
22 #endif
23
24 #define PREV_BUF_SIZE 4096
25 #define RANGE_HEADER_SIZE 30
26
27 char curl_errorstr[CURL_ERROR_SIZE];
28
29 static int curl_ssl_verify = -1;
30 static const char *ssl_cert;
31 #if LIBCURL_VERSION_NUM >= 0x070903
32 static const char *ssl_key;
33 #endif
34 #if LIBCURL_VERSION_NUM >= 0x070908
35 static const char *ssl_capath;
36 #endif
37 static const char *ssl_cainfo;
38 static long curl_low_speed_limit = -1;
39 static long curl_low_speed_time = -1;
40 static int curl_ftp_no_epsv;
41 static const char *curl_http_proxy;
42 static char *user_name, *user_pass;
43
44 #if LIBCURL_VERSION_NUM >= 0x071700
45 /* Use CURLOPT_KEYPASSWD as is */
46 #elif LIBCURL_VERSION_NUM >= 0x070903
47 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
48 #else
49 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
50 #endif
51
52 static char *ssl_cert_password;
53 static int ssl_cert_password_required;
54
55 static struct curl_slist *pragma_header;
56 static struct curl_slist *no_pragma_header;
57
58 static struct active_request_slot *active_queue_head;
59
60 size_t fread_buffer(void *ptr, size_t eltsize, size_t nmemb, void *buffer_)
61 {
62         size_t size = eltsize * nmemb;
63         struct buffer *buffer = buffer_;
64
65         if (size > buffer->buf.len - buffer->posn)
66                 size = buffer->buf.len - buffer->posn;
67         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
68         buffer->posn += size;
69
70         return size;
71 }
72
73 #ifndef NO_CURL_IOCTL
74 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
75 {
76         struct buffer *buffer = clientp;
77
78         switch (cmd) {
79         case CURLIOCMD_NOP:
80                 return CURLIOE_OK;
81
82         case CURLIOCMD_RESTARTREAD:
83                 buffer->posn = 0;
84                 return CURLIOE_OK;
85
86         default:
87                 return CURLIOE_UNKNOWNCMD;
88         }
89 }
90 #endif
91
92 size_t fwrite_buffer(const void *ptr, size_t eltsize, size_t nmemb, void *buffer_)
93 {
94         size_t size = eltsize * nmemb;
95         struct strbuf *buffer = buffer_;
96
97         strbuf_add(buffer, ptr, size);
98         data_received++;
99         return size;
100 }
101
102 size_t fwrite_null(const void *ptr, size_t eltsize, size_t nmemb, void *strbuf)
103 {
104         data_received++;
105         return eltsize * nmemb;
106 }
107
108 #ifdef USE_CURL_MULTI
109 static void process_curl_messages(void)
110 {
111         int num_messages;
112         struct active_request_slot *slot;
113         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
114
115         while (curl_message != NULL) {
116                 if (curl_message->msg == CURLMSG_DONE) {
117                         int curl_result = curl_message->data.result;
118                         slot = active_queue_head;
119                         while (slot != NULL &&
120                                slot->curl != curl_message->easy_handle)
121                                 slot = slot->next;
122                         if (slot != NULL) {
123                                 curl_multi_remove_handle(curlm, slot->curl);
124                                 slot->curl_result = curl_result;
125                                 finish_active_slot(slot);
126                         } else {
127                                 fprintf(stderr, "Received DONE message for unknown request!\n");
128                         }
129                 } else {
130                         fprintf(stderr, "Unknown CURL message received: %d\n",
131                                 (int)curl_message->msg);
132                 }
133                 curl_message = curl_multi_info_read(curlm, &num_messages);
134         }
135 }
136 #endif
137
138 static int http_options(const char *var, const char *value, void *cb)
139 {
140         if (!strcmp("http.sslverify", var)) {
141                 curl_ssl_verify = git_config_bool(var, value);
142                 return 0;
143         }
144         if (!strcmp("http.sslcert", var))
145                 return git_config_string(&ssl_cert, var, value);
146 #if LIBCURL_VERSION_NUM >= 0x070903
147         if (!strcmp("http.sslkey", var))
148                 return git_config_string(&ssl_key, var, value);
149 #endif
150 #if LIBCURL_VERSION_NUM >= 0x070908
151         if (!strcmp("http.sslcapath", var))
152                 return git_config_string(&ssl_capath, var, value);
153 #endif
154         if (!strcmp("http.sslcainfo", var))
155                 return git_config_string(&ssl_cainfo, var, value);
156         if (!strcmp("http.sslcertpasswordprotected", var)) {
157                 if (git_config_bool(var, value))
158                         ssl_cert_password_required = 1;
159                 return 0;
160         }
161         if (!strcmp("http.minsessions", var)) {
162                 min_curl_sessions = git_config_int(var, value);
163 #ifndef USE_CURL_MULTI
164                 if (min_curl_sessions > 1)
165                         min_curl_sessions = 1;
166 #endif
167                 return 0;
168         }
169 #ifdef USE_CURL_MULTI
170         if (!strcmp("http.maxrequests", var)) {
171                 max_requests = git_config_int(var, value);
172                 return 0;
173         }
174 #endif
175         if (!strcmp("http.lowspeedlimit", var)) {
176                 curl_low_speed_limit = (long)git_config_int(var, value);
177                 return 0;
178         }
179         if (!strcmp("http.lowspeedtime", var)) {
180                 curl_low_speed_time = (long)git_config_int(var, value);
181                 return 0;
182         }
183
184         if (!strcmp("http.noepsv", var)) {
185                 curl_ftp_no_epsv = git_config_bool(var, value);
186                 return 0;
187         }
188         if (!strcmp("http.proxy", var))
189                 return git_config_string(&curl_http_proxy, var, value);
190
191         if (!strcmp("http.postbuffer", var)) {
192                 http_post_buffer = git_config_int(var, value);
193                 if (http_post_buffer < LARGE_PACKET_MAX)
194                         http_post_buffer = LARGE_PACKET_MAX;
195                 return 0;
196         }
197
198         /* Fall back on the default ones */
199         return git_default_config(var, value, cb);
200 }
201
202 static void init_curl_http_auth(CURL *result)
203 {
204         if (user_name) {
205                 struct strbuf up = STRBUF_INIT;
206                 if (!user_pass)
207                         user_pass = xstrdup(getpass("Password: "));
208                 strbuf_addf(&up, "%s:%s", user_name, user_pass);
209                 curl_easy_setopt(result, CURLOPT_USERPWD,
210                                  strbuf_detach(&up, NULL));
211         }
212 }
213
214 static int has_cert_password(void)
215 {
216         if (ssl_cert_password != NULL)
217                 return 1;
218         if (ssl_cert == NULL || ssl_cert_password_required != 1)
219                 return 0;
220         /* Only prompt the user once. */
221         ssl_cert_password_required = -1;
222         ssl_cert_password = getpass("Certificate Password: ");
223         if (ssl_cert_password != NULL) {
224                 ssl_cert_password = xstrdup(ssl_cert_password);
225                 return 1;
226         } else
227                 return 0;
228 }
229
230 static CURL *get_curl_handle(void)
231 {
232         CURL *result = curl_easy_init();
233
234         if (!curl_ssl_verify) {
235                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
236                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
237         } else {
238                 /* Verify authenticity of the peer's certificate */
239                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
240                 /* The name in the cert must match whom we tried to connect */
241                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
242         }
243
244 #if LIBCURL_VERSION_NUM >= 0x070907
245         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
246 #endif
247 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
248         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
249 #endif
250
251         init_curl_http_auth(result);
252
253         if (ssl_cert != NULL)
254                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
255         if (has_cert_password())
256                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, ssl_cert_password);
257 #if LIBCURL_VERSION_NUM >= 0x070903
258         if (ssl_key != NULL)
259                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
260 #endif
261 #if LIBCURL_VERSION_NUM >= 0x070908
262         if (ssl_capath != NULL)
263                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
264 #endif
265         if (ssl_cainfo != NULL)
266                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
267         curl_easy_setopt(result, CURLOPT_FAILONERROR, 1);
268
269         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
270                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
271                                  curl_low_speed_limit);
272                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
273                                  curl_low_speed_time);
274         }
275
276         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
277
278         if (getenv("GIT_CURL_VERBOSE"))
279                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
280
281         curl_easy_setopt(result, CURLOPT_USERAGENT, GIT_USER_AGENT);
282
283         if (curl_ftp_no_epsv)
284                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
285
286         if (curl_http_proxy)
287                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
288
289         return result;
290 }
291
292 static void http_auth_init(const char *url)
293 {
294         char *at, *colon, *cp, *slash;
295         int len;
296
297         cp = strstr(url, "://");
298         if (!cp)
299                 return;
300
301         /*
302          * Ok, the URL looks like "proto://something".  Which one?
303          * "proto://<user>:<pass>@<host>/...",
304          * "proto://<user>@<host>/...", or just
305          * "proto://<host>/..."?
306          */
307         cp += 3;
308         at = strchr(cp, '@');
309         colon = strchr(cp, ':');
310         slash = strchrnul(cp, '/');
311         if (!at || slash <= at)
312                 return; /* No credentials */
313         if (!colon || at <= colon) {
314                 /* Only username */
315                 len = at - cp;
316                 user_name = xmalloc(len + 1);
317                 memcpy(user_name, cp, len);
318                 user_name[len] = '\0';
319                 user_pass = NULL;
320         } else {
321                 len = colon - cp;
322                 user_name = xmalloc(len + 1);
323                 memcpy(user_name, cp, len);
324                 user_name[len] = '\0';
325                 len = at - (colon + 1);
326                 user_pass = xmalloc(len + 1);
327                 memcpy(user_pass, colon + 1, len);
328                 user_pass[len] = '\0';
329         }
330 }
331
332 static void set_from_env(const char **var, const char *envname)
333 {
334         const char *val = getenv(envname);
335         if (val)
336                 *var = val;
337 }
338
339 void http_init(struct remote *remote)
340 {
341         char *low_speed_limit;
342         char *low_speed_time;
343
344         http_is_verbose = 0;
345
346         git_config(http_options, NULL);
347
348         curl_global_init(CURL_GLOBAL_ALL);
349
350         if (remote && remote->http_proxy)
351                 curl_http_proxy = xstrdup(remote->http_proxy);
352
353         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
354         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
355
356 #ifdef USE_CURL_MULTI
357         {
358                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
359                 if (http_max_requests != NULL)
360                         max_requests = atoi(http_max_requests);
361         }
362
363         curlm = curl_multi_init();
364         if (curlm == NULL) {
365                 fprintf(stderr, "Error creating curl multi handle.\n");
366                 exit(1);
367         }
368 #endif
369
370         if (getenv("GIT_SSL_NO_VERIFY"))
371                 curl_ssl_verify = 0;
372
373         set_from_env(&ssl_cert, "GIT_SSL_CERT");
374 #if LIBCURL_VERSION_NUM >= 0x070903
375         set_from_env(&ssl_key, "GIT_SSL_KEY");
376 #endif
377 #if LIBCURL_VERSION_NUM >= 0x070908
378         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
379 #endif
380         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
381
382         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
383         if (low_speed_limit != NULL)
384                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
385         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
386         if (low_speed_time != NULL)
387                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
388
389         if (curl_ssl_verify == -1)
390                 curl_ssl_verify = 1;
391
392         curl_session_count = 0;
393 #ifdef USE_CURL_MULTI
394         if (max_requests < 1)
395                 max_requests = DEFAULT_MAX_REQUESTS;
396 #endif
397
398         if (getenv("GIT_CURL_FTP_NO_EPSV"))
399                 curl_ftp_no_epsv = 1;
400
401         if (remote && remote->url && remote->url[0]) {
402                 http_auth_init(remote->url[0]);
403                 if (!ssl_cert_password_required &&
404                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
405                     !prefixcmp(remote->url[0], "https://"))
406                         ssl_cert_password_required = 1;
407         }
408
409 #ifndef NO_CURL_EASY_DUPHANDLE
410         curl_default = get_curl_handle();
411 #endif
412 }
413
414 void http_cleanup(void)
415 {
416         struct active_request_slot *slot = active_queue_head;
417
418         while (slot != NULL) {
419                 struct active_request_slot *next = slot->next;
420                 if (slot->curl != NULL) {
421 #ifdef USE_CURL_MULTI
422                         curl_multi_remove_handle(curlm, slot->curl);
423 #endif
424                         curl_easy_cleanup(slot->curl);
425                 }
426                 free(slot);
427                 slot = next;
428         }
429         active_queue_head = NULL;
430
431 #ifndef NO_CURL_EASY_DUPHANDLE
432         curl_easy_cleanup(curl_default);
433 #endif
434
435 #ifdef USE_CURL_MULTI
436         curl_multi_cleanup(curlm);
437 #endif
438         curl_global_cleanup();
439
440         curl_slist_free_all(pragma_header);
441         pragma_header = NULL;
442
443         curl_slist_free_all(no_pragma_header);
444         no_pragma_header = NULL;
445
446         if (curl_http_proxy) {
447                 free((void *)curl_http_proxy);
448                 curl_http_proxy = NULL;
449         }
450
451         if (ssl_cert_password != NULL) {
452                 memset(ssl_cert_password, 0, strlen(ssl_cert_password));
453                 free(ssl_cert_password);
454                 ssl_cert_password = NULL;
455         }
456         ssl_cert_password_required = 0;
457 }
458
459 struct active_request_slot *get_active_slot(void)
460 {
461         struct active_request_slot *slot = active_queue_head;
462         struct active_request_slot *newslot;
463
464 #ifdef USE_CURL_MULTI
465         int num_transfers;
466
467         /* Wait for a slot to open up if the queue is full */
468         while (active_requests >= max_requests) {
469                 curl_multi_perform(curlm, &num_transfers);
470                 if (num_transfers < active_requests)
471                         process_curl_messages();
472         }
473 #endif
474
475         while (slot != NULL && slot->in_use)
476                 slot = slot->next;
477
478         if (slot == NULL) {
479                 newslot = xmalloc(sizeof(*newslot));
480                 newslot->curl = NULL;
481                 newslot->in_use = 0;
482                 newslot->next = NULL;
483
484                 slot = active_queue_head;
485                 if (slot == NULL) {
486                         active_queue_head = newslot;
487                 } else {
488                         while (slot->next != NULL)
489                                 slot = slot->next;
490                         slot->next = newslot;
491                 }
492                 slot = newslot;
493         }
494
495         if (slot->curl == NULL) {
496 #ifdef NO_CURL_EASY_DUPHANDLE
497                 slot->curl = get_curl_handle();
498 #else
499                 slot->curl = curl_easy_duphandle(curl_default);
500 #endif
501                 curl_session_count++;
502         }
503
504         active_requests++;
505         slot->in_use = 1;
506         slot->local = NULL;
507         slot->results = NULL;
508         slot->finished = NULL;
509         slot->callback_data = NULL;
510         slot->callback_func = NULL;
511         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
512         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
513         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
514         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
515         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
516         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
517         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
518
519         return slot;
520 }
521
522 int start_active_slot(struct active_request_slot *slot)
523 {
524 #ifdef USE_CURL_MULTI
525         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
526         int num_transfers;
527
528         if (curlm_result != CURLM_OK &&
529             curlm_result != CURLM_CALL_MULTI_PERFORM) {
530                 active_requests--;
531                 slot->in_use = 0;
532                 return 0;
533         }
534
535         /*
536          * We know there must be something to do, since we just added
537          * something.
538          */
539         curl_multi_perform(curlm, &num_transfers);
540 #endif
541         return 1;
542 }
543
544 #ifdef USE_CURL_MULTI
545 struct fill_chain {
546         void *data;
547         int (*fill)(void *);
548         struct fill_chain *next;
549 };
550
551 static struct fill_chain *fill_cfg;
552
553 void add_fill_function(void *data, int (*fill)(void *))
554 {
555         struct fill_chain *new = xmalloc(sizeof(*new));
556         struct fill_chain **linkp = &fill_cfg;
557         new->data = data;
558         new->fill = fill;
559         new->next = NULL;
560         while (*linkp)
561                 linkp = &(*linkp)->next;
562         *linkp = new;
563 }
564
565 void fill_active_slots(void)
566 {
567         struct active_request_slot *slot = active_queue_head;
568
569         while (active_requests < max_requests) {
570                 struct fill_chain *fill;
571                 for (fill = fill_cfg; fill; fill = fill->next)
572                         if (fill->fill(fill->data))
573                                 break;
574
575                 if (!fill)
576                         break;
577         }
578
579         while (slot != NULL) {
580                 if (!slot->in_use && slot->curl != NULL
581                         && curl_session_count > min_curl_sessions) {
582                         curl_easy_cleanup(slot->curl);
583                         slot->curl = NULL;
584                         curl_session_count--;
585                 }
586                 slot = slot->next;
587         }
588 }
589
590 void step_active_slots(void)
591 {
592         int num_transfers;
593         CURLMcode curlm_result;
594
595         do {
596                 curlm_result = curl_multi_perform(curlm, &num_transfers);
597         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
598         if (num_transfers < active_requests) {
599                 process_curl_messages();
600                 fill_active_slots();
601         }
602 }
603 #endif
604
605 void run_active_slot(struct active_request_slot *slot)
606 {
607 #ifdef USE_CURL_MULTI
608         long last_pos = 0;
609         long current_pos;
610         fd_set readfds;
611         fd_set writefds;
612         fd_set excfds;
613         int max_fd;
614         struct timeval select_timeout;
615         int finished = 0;
616
617         slot->finished = &finished;
618         while (!finished) {
619                 data_received = 0;
620                 step_active_slots();
621
622                 if (!data_received && slot->local != NULL) {
623                         current_pos = ftell(slot->local);
624                         if (current_pos > last_pos)
625                                 data_received++;
626                         last_pos = current_pos;
627                 }
628
629                 if (slot->in_use && !data_received) {
630                         max_fd = 0;
631                         FD_ZERO(&readfds);
632                         FD_ZERO(&writefds);
633                         FD_ZERO(&excfds);
634                         select_timeout.tv_sec = 0;
635                         select_timeout.tv_usec = 50000;
636                         select(max_fd, &readfds, &writefds,
637                                &excfds, &select_timeout);
638                 }
639         }
640 #else
641         while (slot->in_use) {
642                 slot->curl_result = curl_easy_perform(slot->curl);
643                 finish_active_slot(slot);
644         }
645 #endif
646 }
647
648 static void closedown_active_slot(struct active_request_slot *slot)
649 {
650         active_requests--;
651         slot->in_use = 0;
652 }
653
654 static void release_active_slot(struct active_request_slot *slot)
655 {
656         closedown_active_slot(slot);
657         if (slot->curl && curl_session_count > min_curl_sessions) {
658 #ifdef USE_CURL_MULTI
659                 curl_multi_remove_handle(curlm, slot->curl);
660 #endif
661                 curl_easy_cleanup(slot->curl);
662                 slot->curl = NULL;
663                 curl_session_count--;
664         }
665 #ifdef USE_CURL_MULTI
666         fill_active_slots();
667 #endif
668 }
669
670 void finish_active_slot(struct active_request_slot *slot)
671 {
672         closedown_active_slot(slot);
673         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
674
675         if (slot->finished != NULL)
676                 (*slot->finished) = 1;
677
678         /* Store slot results so they can be read after the slot is reused */
679         if (slot->results != NULL) {
680                 slot->results->curl_result = slot->curl_result;
681                 slot->results->http_code = slot->http_code;
682         }
683
684         /* Run callback if appropriate */
685         if (slot->callback_func != NULL)
686                 slot->callback_func(slot->callback_data);
687 }
688
689 void finish_all_active_slots(void)
690 {
691         struct active_request_slot *slot = active_queue_head;
692
693         while (slot != NULL)
694                 if (slot->in_use) {
695                         run_active_slot(slot);
696                         slot = active_queue_head;
697                 } else {
698                         slot = slot->next;
699                 }
700 }
701
702 /* Helpers for modifying and creating URLs */
703 static inline int needs_quote(int ch)
704 {
705         if (((ch >= 'A') && (ch <= 'Z'))
706                         || ((ch >= 'a') && (ch <= 'z'))
707                         || ((ch >= '0') && (ch <= '9'))
708                         || (ch == '/')
709                         || (ch == '-')
710                         || (ch == '.'))
711                 return 0;
712         return 1;
713 }
714
715 static inline int hex(int v)
716 {
717         if (v < 10)
718                 return '0' + v;
719         else
720                 return 'A' + v - 10;
721 }
722
723 static void end_url_with_slash(struct strbuf *buf, const char *url)
724 {
725         strbuf_addstr(buf, url);
726         if (buf->len && buf->buf[buf->len - 1] != '/')
727                 strbuf_addstr(buf, "/");
728 }
729
730 static char *quote_ref_url(const char *base, const char *ref)
731 {
732         struct strbuf buf = STRBUF_INIT;
733         const char *cp;
734         int ch;
735
736         end_url_with_slash(&buf, base);
737
738         for (cp = ref; (ch = *cp) != 0; cp++)
739                 if (needs_quote(ch))
740                         strbuf_addf(&buf, "%%%02x", ch);
741                 else
742                         strbuf_addch(&buf, *cp);
743
744         return strbuf_detach(&buf, NULL);
745 }
746
747 void append_remote_object_url(struct strbuf *buf, const char *url,
748                               const char *hex,
749                               int only_two_digit_prefix)
750 {
751         end_url_with_slash(buf, url);
752
753         strbuf_addf(buf, "objects/%.*s/", 2, hex);
754         if (!only_two_digit_prefix)
755                 strbuf_addf(buf, "%s", hex+2);
756 }
757
758 char *get_remote_object_url(const char *url, const char *hex,
759                             int only_two_digit_prefix)
760 {
761         struct strbuf buf = STRBUF_INIT;
762         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
763         return strbuf_detach(&buf, NULL);
764 }
765
766 /* http_request() targets */
767 #define HTTP_REQUEST_STRBUF     0
768 #define HTTP_REQUEST_FILE       1
769
770 static int http_request(const char *url, void *result, int target, int options)
771 {
772         struct active_request_slot *slot;
773         struct slot_results results;
774         struct curl_slist *headers = NULL;
775         struct strbuf buf = STRBUF_INIT;
776         int ret;
777
778         slot = get_active_slot();
779         slot->results = &results;
780         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
781
782         if (result == NULL) {
783                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
784         } else {
785                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
786                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
787
788                 if (target == HTTP_REQUEST_FILE) {
789                         long posn = ftell(result);
790                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
791                                          fwrite);
792                         if (posn > 0) {
793                                 strbuf_addf(&buf, "Range: bytes=%ld-", posn);
794                                 headers = curl_slist_append(headers, buf.buf);
795                                 strbuf_reset(&buf);
796                         }
797                         slot->local = result;
798                 } else
799                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
800                                          fwrite_buffer);
801         }
802
803         strbuf_addstr(&buf, "Pragma:");
804         if (options & HTTP_NO_CACHE)
805                 strbuf_addstr(&buf, " no-cache");
806
807         headers = curl_slist_append(headers, buf.buf);
808
809         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
810         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
811
812         if (start_active_slot(slot)) {
813                 run_active_slot(slot);
814                 if (results.curl_result == CURLE_OK)
815                         ret = HTTP_OK;
816                 else if (missing_target(&results))
817                         ret = HTTP_MISSING_TARGET;
818                 else
819                         ret = HTTP_ERROR;
820         } else {
821                 error("Unable to start HTTP request for %s", url);
822                 ret = HTTP_START_FAILED;
823         }
824
825         slot->local = NULL;
826         curl_slist_free_all(headers);
827         strbuf_release(&buf);
828
829         return ret;
830 }
831
832 int http_get_strbuf(const char *url, struct strbuf *result, int options)
833 {
834         return http_request(url, result, HTTP_REQUEST_STRBUF, options);
835 }
836
837 /*
838  * Downloads an url and stores the result in the given file.
839  *
840  * If a previous interrupted download is detected (i.e. a previous temporary
841  * file is still around) the download is resumed.
842  */
843 static int http_get_file(const char *url, const char *filename, int options)
844 {
845         int ret;
846         struct strbuf tmpfile = STRBUF_INIT;
847         FILE *result;
848
849         strbuf_addf(&tmpfile, "%s.temp", filename);
850         result = fopen(tmpfile.buf, "a");
851         if (! result) {
852                 error("Unable to open local file %s", tmpfile.buf);
853                 ret = HTTP_ERROR;
854                 goto cleanup;
855         }
856
857         ret = http_request(url, result, HTTP_REQUEST_FILE, options);
858         fclose(result);
859
860         if ((ret == HTTP_OK) && move_temp_to_file(tmpfile.buf, filename))
861                 ret = HTTP_ERROR;
862 cleanup:
863         strbuf_release(&tmpfile);
864         return ret;
865 }
866
867 int http_error(const char *url, int ret)
868 {
869         /* http_request has already handled HTTP_START_FAILED. */
870         if (ret != HTTP_START_FAILED)
871                 error("%s while accessing %s\n", curl_errorstr, url);
872
873         return ret;
874 }
875
876 int http_fetch_ref(const char *base, struct ref *ref)
877 {
878         char *url;
879         struct strbuf buffer = STRBUF_INIT;
880         int ret = -1;
881
882         url = quote_ref_url(base, ref->name);
883         if (http_get_strbuf(url, &buffer, HTTP_NO_CACHE) == HTTP_OK) {
884                 strbuf_rtrim(&buffer);
885                 if (buffer.len == 40)
886                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
887                 else if (!prefixcmp(buffer.buf, "ref: ")) {
888                         ref->symref = xstrdup(buffer.buf + 5);
889                         ret = 0;
890                 }
891         }
892
893         strbuf_release(&buffer);
894         free(url);
895         return ret;
896 }
897
898 /* Helpers for fetching packs */
899 static int fetch_pack_index(unsigned char *sha1, const char *base_url)
900 {
901         int ret = 0;
902         char *hex = xstrdup(sha1_to_hex(sha1));
903         char *filename;
904         char *url = NULL;
905         struct strbuf buf = STRBUF_INIT;
906
907         if (has_pack_index(sha1)) {
908                 ret = 0;
909                 goto cleanup;
910         }
911
912         if (http_is_verbose)
913                 fprintf(stderr, "Getting index for pack %s\n", hex);
914
915         end_url_with_slash(&buf, base_url);
916         strbuf_addf(&buf, "objects/pack/pack-%s.idx", hex);
917         url = strbuf_detach(&buf, NULL);
918
919         filename = sha1_pack_index_name(sha1);
920         if (http_get_file(url, filename, 0) != HTTP_OK)
921                 ret = error("Unable to get pack index %s\n", url);
922
923 cleanup:
924         free(hex);
925         free(url);
926         return ret;
927 }
928
929 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
930         unsigned char *sha1, const char *base_url)
931 {
932         struct packed_git *new_pack;
933
934         if (fetch_pack_index(sha1, base_url))
935                 return -1;
936
937         new_pack = parse_pack_index(sha1);
938         if (!new_pack)
939                 return -1; /* parse_pack_index() already issued error message */
940         new_pack->next = *packs_head;
941         *packs_head = new_pack;
942         return 0;
943 }
944
945 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
946 {
947         int ret = 0, i = 0;
948         char *url, *data;
949         struct strbuf buf = STRBUF_INIT;
950         unsigned char sha1[20];
951
952         end_url_with_slash(&buf, base_url);
953         strbuf_addstr(&buf, "objects/info/packs");
954         url = strbuf_detach(&buf, NULL);
955
956         ret = http_get_strbuf(url, &buf, HTTP_NO_CACHE);
957         if (ret != HTTP_OK)
958                 goto cleanup;
959
960         data = buf.buf;
961         while (i < buf.len) {
962                 switch (data[i]) {
963                 case 'P':
964                         i++;
965                         if (i + 52 <= buf.len &&
966                             !prefixcmp(data + i, " pack-") &&
967                             !prefixcmp(data + i + 46, ".pack\n")) {
968                                 get_sha1_hex(data + i + 6, sha1);
969                                 fetch_and_setup_pack_index(packs_head, sha1,
970                                                       base_url);
971                                 i += 51;
972                                 break;
973                         }
974                 default:
975                         while (i < buf.len && data[i] != '\n')
976                                 i++;
977                 }
978                 i++;
979         }
980
981 cleanup:
982         free(url);
983         return ret;
984 }
985
986 void release_http_pack_request(struct http_pack_request *preq)
987 {
988         if (preq->packfile != NULL) {
989                 fclose(preq->packfile);
990                 preq->packfile = NULL;
991                 preq->slot->local = NULL;
992         }
993         if (preq->range_header != NULL) {
994                 curl_slist_free_all(preq->range_header);
995                 preq->range_header = NULL;
996         }
997         preq->slot = NULL;
998         free(preq->url);
999 }
1000
1001 int finish_http_pack_request(struct http_pack_request *preq)
1002 {
1003         int ret;
1004         struct packed_git **lst;
1005
1006         preq->target->pack_size = ftell(preq->packfile);
1007
1008         if (preq->packfile != NULL) {
1009                 fclose(preq->packfile);
1010                 preq->packfile = NULL;
1011                 preq->slot->local = NULL;
1012         }
1013
1014         ret = move_temp_to_file(preq->tmpfile, preq->filename);
1015         if (ret)
1016                 return ret;
1017
1018         lst = preq->lst;
1019         while (*lst != preq->target)
1020                 lst = &((*lst)->next);
1021         *lst = (*lst)->next;
1022
1023         if (verify_pack(preq->target))
1024                 return -1;
1025         install_packed_git(preq->target);
1026
1027         return 0;
1028 }
1029
1030 struct http_pack_request *new_http_pack_request(
1031         struct packed_git *target, const char *base_url)
1032 {
1033         char *filename;
1034         long prev_posn = 0;
1035         char range[RANGE_HEADER_SIZE];
1036         struct strbuf buf = STRBUF_INIT;
1037         struct http_pack_request *preq;
1038
1039         preq = xmalloc(sizeof(*preq));
1040         preq->target = target;
1041         preq->range_header = NULL;
1042
1043         end_url_with_slash(&buf, base_url);
1044         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1045                 sha1_to_hex(target->sha1));
1046         preq->url = strbuf_detach(&buf, NULL);
1047
1048         filename = sha1_pack_name(target->sha1);
1049         snprintf(preq->filename, sizeof(preq->filename), "%s", filename);
1050         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp", filename);
1051         preq->packfile = fopen(preq->tmpfile, "a");
1052         if (!preq->packfile) {
1053                 error("Unable to open local file %s for pack",
1054                       preq->tmpfile);
1055                 goto abort;
1056         }
1057
1058         preq->slot = get_active_slot();
1059         preq->slot->local = preq->packfile;
1060         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1061         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1062         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1063         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1064                 no_pragma_header);
1065
1066         /*
1067          * If there is data present from a previous transfer attempt,
1068          * resume where it left off
1069          */
1070         prev_posn = ftell(preq->packfile);
1071         if (prev_posn>0) {
1072                 if (http_is_verbose)
1073                         fprintf(stderr,
1074                                 "Resuming fetch of pack %s at byte %ld\n",
1075                                 sha1_to_hex(target->sha1), prev_posn);
1076                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1077                 preq->range_header = curl_slist_append(NULL, range);
1078                 curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1079                         preq->range_header);
1080         }
1081
1082         return preq;
1083
1084 abort:
1085         free(filename);
1086         free(preq->url);
1087         free(preq);
1088         return NULL;
1089 }
1090
1091 /* Helpers for fetching objects (loose) */
1092 static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb,
1093                                void *data)
1094 {
1095         unsigned char expn[4096];
1096         size_t size = eltsize * nmemb;
1097         int posn = 0;
1098         struct http_object_request *freq =
1099                 (struct http_object_request *)data;
1100         do {
1101                 ssize_t retval = xwrite(freq->localfile,
1102                                         (char *) ptr + posn, size - posn);
1103                 if (retval < 0)
1104                         return posn;
1105                 posn += retval;
1106         } while (posn < size);
1107
1108         freq->stream.avail_in = size;
1109         freq->stream.next_in = ptr;
1110         do {
1111                 freq->stream.next_out = expn;
1112                 freq->stream.avail_out = sizeof(expn);
1113                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1114                 git_SHA1_Update(&freq->c, expn,
1115                                 sizeof(expn) - freq->stream.avail_out);
1116         } while (freq->stream.avail_in && freq->zret == Z_OK);
1117         data_received++;
1118         return size;
1119 }
1120
1121 struct http_object_request *new_http_object_request(const char *base_url,
1122         unsigned char *sha1)
1123 {
1124         char *hex = sha1_to_hex(sha1);
1125         char *filename;
1126         char prevfile[PATH_MAX];
1127         int prevlocal;
1128         unsigned char prev_buf[PREV_BUF_SIZE];
1129         ssize_t prev_read = 0;
1130         long prev_posn = 0;
1131         char range[RANGE_HEADER_SIZE];
1132         struct curl_slist *range_header = NULL;
1133         struct http_object_request *freq;
1134
1135         freq = xmalloc(sizeof(*freq));
1136         hashcpy(freq->sha1, sha1);
1137         freq->localfile = -1;
1138
1139         filename = sha1_file_name(sha1);
1140         snprintf(freq->filename, sizeof(freq->filename), "%s", filename);
1141         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1142                  "%s.temp", filename);
1143
1144         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1145         unlink_or_warn(prevfile);
1146         rename(freq->tmpfile, prevfile);
1147         unlink_or_warn(freq->tmpfile);
1148
1149         if (freq->localfile != -1)
1150                 error("fd leakage in start: %d", freq->localfile);
1151         freq->localfile = open(freq->tmpfile,
1152                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1153         /*
1154          * This could have failed due to the "lazy directory creation";
1155          * try to mkdir the last path component.
1156          */
1157         if (freq->localfile < 0 && errno == ENOENT) {
1158                 char *dir = strrchr(freq->tmpfile, '/');
1159                 if (dir) {
1160                         *dir = 0;
1161                         mkdir(freq->tmpfile, 0777);
1162                         *dir = '/';
1163                 }
1164                 freq->localfile = open(freq->tmpfile,
1165                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1166         }
1167
1168         if (freq->localfile < 0) {
1169                 error("Couldn't create temporary file %s for %s: %s",
1170                       freq->tmpfile, freq->filename, strerror(errno));
1171                 goto abort;
1172         }
1173
1174         memset(&freq->stream, 0, sizeof(freq->stream));
1175
1176         git_inflate_init(&freq->stream);
1177
1178         git_SHA1_Init(&freq->c);
1179
1180         freq->url = get_remote_object_url(base_url, hex, 0);
1181
1182         /*
1183          * If a previous temp file is present, process what was already
1184          * fetched.
1185          */
1186         prevlocal = open(prevfile, O_RDONLY);
1187         if (prevlocal != -1) {
1188                 do {
1189                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1190                         if (prev_read>0) {
1191                                 if (fwrite_sha1_file(prev_buf,
1192                                                      1,
1193                                                      prev_read,
1194                                                      freq) == prev_read) {
1195                                         prev_posn += prev_read;
1196                                 } else {
1197                                         prev_read = -1;
1198                                 }
1199                         }
1200                 } while (prev_read > 0);
1201                 close(prevlocal);
1202         }
1203         unlink_or_warn(prevfile);
1204
1205         /*
1206          * Reset inflate/SHA1 if there was an error reading the previous temp
1207          * file; also rewind to the beginning of the local file.
1208          */
1209         if (prev_read == -1) {
1210                 memset(&freq->stream, 0, sizeof(freq->stream));
1211                 git_inflate_init(&freq->stream);
1212                 git_SHA1_Init(&freq->c);
1213                 if (prev_posn>0) {
1214                         prev_posn = 0;
1215                         lseek(freq->localfile, 0, SEEK_SET);
1216                         if (ftruncate(freq->localfile, 0) < 0) {
1217                                 error("Couldn't truncate temporary file %s for %s: %s",
1218                                           freq->tmpfile, freq->filename, strerror(errno));
1219                                 goto abort;
1220                         }
1221                 }
1222         }
1223
1224         freq->slot = get_active_slot();
1225
1226         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1227         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1228         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1229         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1230         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1231
1232         /*
1233          * If we have successfully processed data from a previous fetch
1234          * attempt, only fetch the data we don't already have.
1235          */
1236         if (prev_posn>0) {
1237                 if (http_is_verbose)
1238                         fprintf(stderr,
1239                                 "Resuming fetch of object %s at byte %ld\n",
1240                                 hex, prev_posn);
1241                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1242                 range_header = curl_slist_append(range_header, range);
1243                 curl_easy_setopt(freq->slot->curl,
1244                                  CURLOPT_HTTPHEADER, range_header);
1245         }
1246
1247         return freq;
1248
1249 abort:
1250         free(filename);
1251         free(freq->url);
1252         free(freq);
1253         return NULL;
1254 }
1255
1256 void process_http_object_request(struct http_object_request *freq)
1257 {
1258         if (freq->slot == NULL)
1259                 return;
1260         freq->curl_result = freq->slot->curl_result;
1261         freq->http_code = freq->slot->http_code;
1262         freq->slot = NULL;
1263 }
1264
1265 int finish_http_object_request(struct http_object_request *freq)
1266 {
1267         struct stat st;
1268
1269         close(freq->localfile);
1270         freq->localfile = -1;
1271
1272         process_http_object_request(freq);
1273
1274         if (freq->http_code == 416) {
1275                 warning("requested range invalid; we may already have all the data.");
1276         } else if (freq->curl_result != CURLE_OK) {
1277                 if (stat(freq->tmpfile, &st) == 0)
1278                         if (st.st_size == 0)
1279                                 unlink_or_warn(freq->tmpfile);
1280                 return -1;
1281         }
1282
1283         git_inflate_end(&freq->stream);
1284         git_SHA1_Final(freq->real_sha1, &freq->c);
1285         if (freq->zret != Z_STREAM_END) {
1286                 unlink_or_warn(freq->tmpfile);
1287                 return -1;
1288         }
1289         if (hashcmp(freq->sha1, freq->real_sha1)) {
1290                 unlink_or_warn(freq->tmpfile);
1291                 return -1;
1292         }
1293         freq->rename =
1294                 move_temp_to_file(freq->tmpfile, freq->filename);
1295
1296         return freq->rename;
1297 }
1298
1299 void abort_http_object_request(struct http_object_request *freq)
1300 {
1301         unlink_or_warn(freq->tmpfile);
1302
1303         release_http_object_request(freq);
1304 }
1305
1306 void release_http_object_request(struct http_object_request *freq)
1307 {
1308         if (freq->localfile != -1) {
1309                 close(freq->localfile);
1310                 freq->localfile = -1;
1311         }
1312         if (freq->url != NULL) {
1313                 free(freq->url);
1314                 freq->url = NULL;
1315         }
1316         if (freq->slot != NULL) {
1317                 freq->slot->callback_func = NULL;
1318                 freq->slot->callback_data = NULL;
1319                 release_active_slot(freq->slot);
1320                 freq->slot = NULL;
1321         }
1322 }