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