Merge branch 'en/rebase-against-rebase-fix' into maint
[git] / http.c
1 #include "http.h"
2 #include "pack.h"
3 #include "sideband.h"
4 #include "run-command.h"
5
6 int data_received;
7 int active_requests;
8 int http_is_verbose;
9 size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
10
11 #if LIBCURL_VERSION_NUM >= 0x070a06
12 #define LIBCURL_CAN_HANDLE_AUTH_ANY
13 #endif
14
15 static int min_curl_sessions = 1;
16 static int curl_session_count;
17 #ifdef USE_CURL_MULTI
18 static int max_requests = -1;
19 static CURLM *curlm;
20 #endif
21 #ifndef NO_CURL_EASY_DUPHANDLE
22 static CURL *curl_default;
23 #endif
24
25 #define PREV_BUF_SIZE 4096
26 #define RANGE_HEADER_SIZE 30
27
28 char curl_errorstr[CURL_ERROR_SIZE];
29
30 static int curl_ssl_verify = -1;
31 static const char *ssl_cert;
32 #if LIBCURL_VERSION_NUM >= 0x070903
33 static const char *ssl_key;
34 #endif
35 #if LIBCURL_VERSION_NUM >= 0x070908
36 static const char *ssl_capath;
37 #endif
38 static const char *ssl_cainfo;
39 static long curl_low_speed_limit = -1;
40 static long curl_low_speed_time = -1;
41 static int curl_ftp_no_epsv;
42 static const char *curl_http_proxy;
43 static char *user_name, *user_pass;
44
45 #if LIBCURL_VERSION_NUM >= 0x071700
46 /* Use CURLOPT_KEYPASSWD as is */
47 #elif LIBCURL_VERSION_NUM >= 0x070903
48 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
49 #else
50 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
51 #endif
52
53 static char *ssl_cert_password;
54 static int ssl_cert_password_required;
55
56 static struct curl_slist *pragma_header;
57 static struct curl_slist *no_pragma_header;
58
59 static struct active_request_slot *active_queue_head;
60
61 size_t fread_buffer(void *ptr, size_t eltsize, size_t nmemb, void *buffer_)
62 {
63         size_t size = eltsize * nmemb;
64         struct buffer *buffer = buffer_;
65
66         if (size > buffer->buf.len - buffer->posn)
67                 size = buffer->buf.len - buffer->posn;
68         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
69         buffer->posn += size;
70
71         return size;
72 }
73
74 #ifndef NO_CURL_IOCTL
75 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
76 {
77         struct buffer *buffer = clientp;
78
79         switch (cmd) {
80         case CURLIOCMD_NOP:
81                 return CURLIOE_OK;
82
83         case CURLIOCMD_RESTARTREAD:
84                 buffer->posn = 0;
85                 return CURLIOE_OK;
86
87         default:
88                 return CURLIOE_UNKNOWNCMD;
89         }
90 }
91 #endif
92
93 size_t fwrite_buffer(const void *ptr, size_t eltsize, size_t nmemb, void *buffer_)
94 {
95         size_t size = eltsize * nmemb;
96         struct strbuf *buffer = buffer_;
97
98         strbuf_add(buffer, ptr, size);
99         data_received++;
100         return size;
101 }
102
103 size_t fwrite_null(const void *ptr, size_t eltsize, size_t nmemb, void *strbuf)
104 {
105         data_received++;
106         return eltsize * nmemb;
107 }
108
109 #ifdef USE_CURL_MULTI
110 static void process_curl_messages(void)
111 {
112         int num_messages;
113         struct active_request_slot *slot;
114         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
115
116         while (curl_message != NULL) {
117                 if (curl_message->msg == CURLMSG_DONE) {
118                         int curl_result = curl_message->data.result;
119                         slot = active_queue_head;
120                         while (slot != NULL &&
121                                slot->curl != curl_message->easy_handle)
122                                 slot = slot->next;
123                         if (slot != NULL) {
124                                 curl_multi_remove_handle(curlm, slot->curl);
125                                 slot->curl_result = curl_result;
126                                 finish_active_slot(slot);
127                         } else {
128                                 fprintf(stderr, "Received DONE message for unknown request!\n");
129                         }
130                 } else {
131                         fprintf(stderr, "Unknown CURL message received: %d\n",
132                                 (int)curl_message->msg);
133                 }
134                 curl_message = curl_multi_info_read(curlm, &num_messages);
135         }
136 }
137 #endif
138
139 static int http_options(const char *var, const char *value, void *cb)
140 {
141         if (!strcmp("http.sslverify", var)) {
142                 curl_ssl_verify = git_config_bool(var, value);
143                 return 0;
144         }
145         if (!strcmp("http.sslcert", var))
146                 return git_config_string(&ssl_cert, var, value);
147 #if LIBCURL_VERSION_NUM >= 0x070903
148         if (!strcmp("http.sslkey", var))
149                 return git_config_string(&ssl_key, var, value);
150 #endif
151 #if LIBCURL_VERSION_NUM >= 0x070908
152         if (!strcmp("http.sslcapath", var))
153                 return git_config_string(&ssl_capath, var, value);
154 #endif
155         if (!strcmp("http.sslcainfo", var))
156                 return git_config_string(&ssl_cainfo, var, value);
157         if (!strcmp("http.sslcertpasswordprotected", var)) {
158                 if (git_config_bool(var, value))
159                         ssl_cert_password_required = 1;
160                 return 0;
161         }
162         if (!strcmp("http.minsessions", var)) {
163                 min_curl_sessions = git_config_int(var, value);
164 #ifndef USE_CURL_MULTI
165                 if (min_curl_sessions > 1)
166                         min_curl_sessions = 1;
167 #endif
168                 return 0;
169         }
170 #ifdef USE_CURL_MULTI
171         if (!strcmp("http.maxrequests", var)) {
172                 max_requests = git_config_int(var, value);
173                 return 0;
174         }
175 #endif
176         if (!strcmp("http.lowspeedlimit", var)) {
177                 curl_low_speed_limit = (long)git_config_int(var, value);
178                 return 0;
179         }
180         if (!strcmp("http.lowspeedtime", var)) {
181                 curl_low_speed_time = (long)git_config_int(var, value);
182                 return 0;
183         }
184
185         if (!strcmp("http.noepsv", var)) {
186                 curl_ftp_no_epsv = git_config_bool(var, value);
187                 return 0;
188         }
189         if (!strcmp("http.proxy", var))
190                 return git_config_string(&curl_http_proxy, var, value);
191
192         if (!strcmp("http.postbuffer", var)) {
193                 http_post_buffer = git_config_int(var, value);
194                 if (http_post_buffer < LARGE_PACKET_MAX)
195                         http_post_buffer = LARGE_PACKET_MAX;
196                 return 0;
197         }
198
199         /* Fall back on the default ones */
200         return git_default_config(var, value, cb);
201 }
202
203 static void init_curl_http_auth(CURL *result)
204 {
205         if (user_name) {
206                 struct strbuf up = STRBUF_INIT;
207                 if (!user_pass)
208                         user_pass = xstrdup(git_getpass("Password: "));
209                 strbuf_addf(&up, "%s:%s", user_name, user_pass);
210                 curl_easy_setopt(result, CURLOPT_USERPWD,
211                                  strbuf_detach(&up, NULL));
212         }
213 }
214
215 static int has_cert_password(void)
216 {
217         if (ssl_cert_password != NULL)
218                 return 1;
219         if (ssl_cert == NULL || ssl_cert_password_required != 1)
220                 return 0;
221         /* Only prompt the user once. */
222         ssl_cert_password_required = -1;
223         ssl_cert_password = git_getpass("Certificate Password: ");
224         if (ssl_cert_password != NULL) {
225                 ssl_cert_password = xstrdup(ssl_cert_password);
226                 return 1;
227         } else
228                 return 0;
229 }
230
231 static CURL *get_curl_handle(void)
232 {
233         CURL *result = curl_easy_init();
234
235         if (!curl_ssl_verify) {
236                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
237                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
238         } else {
239                 /* Verify authenticity of the peer's certificate */
240                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
241                 /* The name in the cert must match whom we tried to connect */
242                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
243         }
244
245 #if LIBCURL_VERSION_NUM >= 0x070907
246         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
247 #endif
248 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
249         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
250 #endif
251
252         init_curl_http_auth(result);
253
254         if (ssl_cert != NULL)
255                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
256         if (has_cert_password())
257                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, ssl_cert_password);
258 #if LIBCURL_VERSION_NUM >= 0x070903
259         if (ssl_key != NULL)
260                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
261 #endif
262 #if LIBCURL_VERSION_NUM >= 0x070908
263         if (ssl_capath != NULL)
264                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
265 #endif
266         if (ssl_cainfo != NULL)
267                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
268         curl_easy_setopt(result, CURLOPT_FAILONERROR, 1);
269
270         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
271                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
272                                  curl_low_speed_limit);
273                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
274                                  curl_low_speed_time);
275         }
276
277         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
278
279         if (getenv("GIT_CURL_VERBOSE"))
280                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
281
282         curl_easy_setopt(result, CURLOPT_USERAGENT, GIT_USER_AGENT);
283
284         if (curl_ftp_no_epsv)
285                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
286
287         if (curl_http_proxy)
288                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
289
290         return result;
291 }
292
293 static void http_auth_init(const char *url)
294 {
295         char *at, *colon, *cp, *slash;
296         int len;
297
298         cp = strstr(url, "://");
299         if (!cp)
300                 return;
301
302         /*
303          * Ok, the URL looks like "proto://something".  Which one?
304          * "proto://<user>:<pass>@<host>/...",
305          * "proto://<user>@<host>/...", or just
306          * "proto://<host>/..."?
307          */
308         cp += 3;
309         at = strchr(cp, '@');
310         colon = strchr(cp, ':');
311         slash = strchrnul(cp, '/');
312         if (!at || slash <= at)
313                 return; /* No credentials */
314         if (!colon || at <= colon) {
315                 /* Only username */
316                 len = at - cp;
317                 user_name = xmalloc(len + 1);
318                 memcpy(user_name, cp, len);
319                 user_name[len] = '\0';
320                 user_pass = NULL;
321         } else {
322                 len = colon - cp;
323                 user_name = xmalloc(len + 1);
324                 memcpy(user_name, cp, len);
325                 user_name[len] = '\0';
326                 len = at - (colon + 1);
327                 user_pass = xmalloc(len + 1);
328                 memcpy(user_pass, colon + 1, len);
329                 user_pass[len] = '\0';
330         }
331 }
332
333 static void set_from_env(const char **var, const char *envname)
334 {
335         const char *val = getenv(envname);
336         if (val)
337                 *var = val;
338 }
339
340 void http_init(struct remote *remote)
341 {
342         char *low_speed_limit;
343         char *low_speed_time;
344
345         http_is_verbose = 0;
346
347         git_config(http_options, NULL);
348
349         curl_global_init(CURL_GLOBAL_ALL);
350
351         if (remote && remote->http_proxy)
352                 curl_http_proxy = xstrdup(remote->http_proxy);
353
354         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
355         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
356
357 #ifdef USE_CURL_MULTI
358         {
359                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
360                 if (http_max_requests != NULL)
361                         max_requests = atoi(http_max_requests);
362         }
363
364         curlm = curl_multi_init();
365         if (curlm == NULL) {
366                 fprintf(stderr, "Error creating curl multi handle.\n");
367                 exit(1);
368         }
369 #endif
370
371         if (getenv("GIT_SSL_NO_VERIFY"))
372                 curl_ssl_verify = 0;
373
374         set_from_env(&ssl_cert, "GIT_SSL_CERT");
375 #if LIBCURL_VERSION_NUM >= 0x070903
376         set_from_env(&ssl_key, "GIT_SSL_KEY");
377 #endif
378 #if LIBCURL_VERSION_NUM >= 0x070908
379         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
380 #endif
381         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
382
383         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
384         if (low_speed_limit != NULL)
385                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
386         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
387         if (low_speed_time != NULL)
388                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
389
390         if (curl_ssl_verify == -1)
391                 curl_ssl_verify = 1;
392
393         curl_session_count = 0;
394 #ifdef USE_CURL_MULTI
395         if (max_requests < 1)
396                 max_requests = DEFAULT_MAX_REQUESTS;
397 #endif
398
399         if (getenv("GIT_CURL_FTP_NO_EPSV"))
400                 curl_ftp_no_epsv = 1;
401
402         if (remote && remote->url && remote->url[0]) {
403                 http_auth_init(remote->url[0]);
404                 if (!ssl_cert_password_required &&
405                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
406                     !prefixcmp(remote->url[0], "https://"))
407                         ssl_cert_password_required = 1;
408         }
409
410 #ifndef NO_CURL_EASY_DUPHANDLE
411         curl_default = get_curl_handle();
412 #endif
413 }
414
415 void http_cleanup(void)
416 {
417         struct active_request_slot *slot = active_queue_head;
418
419         while (slot != NULL) {
420                 struct active_request_slot *next = slot->next;
421                 if (slot->curl != NULL) {
422 #ifdef USE_CURL_MULTI
423                         curl_multi_remove_handle(curlm, slot->curl);
424 #endif
425                         curl_easy_cleanup(slot->curl);
426                 }
427                 free(slot);
428                 slot = next;
429         }
430         active_queue_head = NULL;
431
432 #ifndef NO_CURL_EASY_DUPHANDLE
433         curl_easy_cleanup(curl_default);
434 #endif
435
436 #ifdef USE_CURL_MULTI
437         curl_multi_cleanup(curlm);
438 #endif
439         curl_global_cleanup();
440
441         curl_slist_free_all(pragma_header);
442         pragma_header = NULL;
443
444         curl_slist_free_all(no_pragma_header);
445         no_pragma_header = NULL;
446
447         if (curl_http_proxy) {
448                 free((void *)curl_http_proxy);
449                 curl_http_proxy = NULL;
450         }
451
452         if (ssl_cert_password != NULL) {
453                 memset(ssl_cert_password, 0, strlen(ssl_cert_password));
454                 free(ssl_cert_password);
455                 ssl_cert_password = NULL;
456         }
457         ssl_cert_password_required = 0;
458 }
459
460 struct active_request_slot *get_active_slot(void)
461 {
462         struct active_request_slot *slot = active_queue_head;
463         struct active_request_slot *newslot;
464
465 #ifdef USE_CURL_MULTI
466         int num_transfers;
467
468         /* Wait for a slot to open up if the queue is full */
469         while (active_requests >= max_requests) {
470                 curl_multi_perform(curlm, &num_transfers);
471                 if (num_transfers < active_requests)
472                         process_curl_messages();
473         }
474 #endif
475
476         while (slot != NULL && slot->in_use)
477                 slot = slot->next;
478
479         if (slot == NULL) {
480                 newslot = xmalloc(sizeof(*newslot));
481                 newslot->curl = NULL;
482                 newslot->in_use = 0;
483                 newslot->next = NULL;
484
485                 slot = active_queue_head;
486                 if (slot == NULL) {
487                         active_queue_head = newslot;
488                 } else {
489                         while (slot->next != NULL)
490                                 slot = slot->next;
491                         slot->next = newslot;
492                 }
493                 slot = newslot;
494         }
495
496         if (slot->curl == NULL) {
497 #ifdef NO_CURL_EASY_DUPHANDLE
498                 slot->curl = get_curl_handle();
499 #else
500                 slot->curl = curl_easy_duphandle(curl_default);
501 #endif
502                 curl_session_count++;
503         }
504
505         active_requests++;
506         slot->in_use = 1;
507         slot->local = NULL;
508         slot->results = NULL;
509         slot->finished = NULL;
510         slot->callback_data = NULL;
511         slot->callback_func = NULL;
512         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
513         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
514         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
515         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
516         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
517         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
518         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
519
520         return slot;
521 }
522
523 int start_active_slot(struct active_request_slot *slot)
524 {
525 #ifdef USE_CURL_MULTI
526         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
527         int num_transfers;
528
529         if (curlm_result != CURLM_OK &&
530             curlm_result != CURLM_CALL_MULTI_PERFORM) {
531                 active_requests--;
532                 slot->in_use = 0;
533                 return 0;
534         }
535
536         /*
537          * We know there must be something to do, since we just added
538          * something.
539          */
540         curl_multi_perform(curlm, &num_transfers);
541 #endif
542         return 1;
543 }
544
545 #ifdef USE_CURL_MULTI
546 struct fill_chain {
547         void *data;
548         int (*fill)(void *);
549         struct fill_chain *next;
550 };
551
552 static struct fill_chain *fill_cfg;
553
554 void add_fill_function(void *data, int (*fill)(void *))
555 {
556         struct fill_chain *new = xmalloc(sizeof(*new));
557         struct fill_chain **linkp = &fill_cfg;
558         new->data = data;
559         new->fill = fill;
560         new->next = NULL;
561         while (*linkp)
562                 linkp = &(*linkp)->next;
563         *linkp = new;
564 }
565
566 void fill_active_slots(void)
567 {
568         struct active_request_slot *slot = active_queue_head;
569
570         while (active_requests < max_requests) {
571                 struct fill_chain *fill;
572                 for (fill = fill_cfg; fill; fill = fill->next)
573                         if (fill->fill(fill->data))
574                                 break;
575
576                 if (!fill)
577                         break;
578         }
579
580         while (slot != NULL) {
581                 if (!slot->in_use && slot->curl != NULL
582                         && curl_session_count > min_curl_sessions) {
583                         curl_easy_cleanup(slot->curl);
584                         slot->curl = NULL;
585                         curl_session_count--;
586                 }
587                 slot = slot->next;
588         }
589 }
590
591 void step_active_slots(void)
592 {
593         int num_transfers;
594         CURLMcode curlm_result;
595
596         do {
597                 curlm_result = curl_multi_perform(curlm, &num_transfers);
598         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
599         if (num_transfers < active_requests) {
600                 process_curl_messages();
601                 fill_active_slots();
602         }
603 }
604 #endif
605
606 void run_active_slot(struct active_request_slot *slot)
607 {
608 #ifdef USE_CURL_MULTI
609         long last_pos = 0;
610         long current_pos;
611         fd_set readfds;
612         fd_set writefds;
613         fd_set excfds;
614         int max_fd;
615         struct timeval select_timeout;
616         int finished = 0;
617
618         slot->finished = &finished;
619         while (!finished) {
620                 data_received = 0;
621                 step_active_slots();
622
623                 if (!data_received && slot->local != NULL) {
624                         current_pos = ftell(slot->local);
625                         if (current_pos > last_pos)
626                                 data_received++;
627                         last_pos = current_pos;
628                 }
629
630                 if (slot->in_use && !data_received) {
631                         max_fd = 0;
632                         FD_ZERO(&readfds);
633                         FD_ZERO(&writefds);
634                         FD_ZERO(&excfds);
635                         select_timeout.tv_sec = 0;
636                         select_timeout.tv_usec = 50000;
637                         select(max_fd, &readfds, &writefds,
638                                &excfds, &select_timeout);
639                 }
640         }
641 #else
642         while (slot->in_use) {
643                 slot->curl_result = curl_easy_perform(slot->curl);
644                 finish_active_slot(slot);
645         }
646 #endif
647 }
648
649 static void closedown_active_slot(struct active_request_slot *slot)
650 {
651         active_requests--;
652         slot->in_use = 0;
653 }
654
655 static void release_active_slot(struct active_request_slot *slot)
656 {
657         closedown_active_slot(slot);
658         if (slot->curl && curl_session_count > min_curl_sessions) {
659 #ifdef USE_CURL_MULTI
660                 curl_multi_remove_handle(curlm, slot->curl);
661 #endif
662                 curl_easy_cleanup(slot->curl);
663                 slot->curl = NULL;
664                 curl_session_count--;
665         }
666 #ifdef USE_CURL_MULTI
667         fill_active_slots();
668 #endif
669 }
670
671 void finish_active_slot(struct active_request_slot *slot)
672 {
673         closedown_active_slot(slot);
674         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
675
676         if (slot->finished != NULL)
677                 (*slot->finished) = 1;
678
679         /* Store slot results so they can be read after the slot is reused */
680         if (slot->results != NULL) {
681                 slot->results->curl_result = slot->curl_result;
682                 slot->results->http_code = slot->http_code;
683         }
684
685         /* Run callback if appropriate */
686         if (slot->callback_func != NULL)
687                 slot->callback_func(slot->callback_data);
688 }
689
690 void finish_all_active_slots(void)
691 {
692         struct active_request_slot *slot = active_queue_head;
693
694         while (slot != NULL)
695                 if (slot->in_use) {
696                         run_active_slot(slot);
697                         slot = active_queue_head;
698                 } else {
699                         slot = slot->next;
700                 }
701 }
702
703 /* Helpers for modifying and creating URLs */
704 static inline int needs_quote(int ch)
705 {
706         if (((ch >= 'A') && (ch <= 'Z'))
707                         || ((ch >= 'a') && (ch <= 'z'))
708                         || ((ch >= '0') && (ch <= '9'))
709                         || (ch == '/')
710                         || (ch == '-')
711                         || (ch == '.'))
712                 return 0;
713         return 1;
714 }
715
716 static inline int hex(int v)
717 {
718         if (v < 10)
719                 return '0' + v;
720         else
721                 return 'A' + v - 10;
722 }
723
724 void end_url_with_slash(struct strbuf *buf, const char *url)
725 {
726         strbuf_addstr(buf, url);
727         if (buf->len && buf->buf[buf->len - 1] != '/')
728                 strbuf_addstr(buf, "/");
729 }
730
731 static char *quote_ref_url(const char *base, const char *ref)
732 {
733         struct strbuf buf = STRBUF_INIT;
734         const char *cp;
735         int ch;
736
737         end_url_with_slash(&buf, base);
738
739         for (cp = ref; (ch = *cp) != 0; cp++)
740                 if (needs_quote(ch))
741                         strbuf_addf(&buf, "%%%02x", ch);
742                 else
743                         strbuf_addch(&buf, *cp);
744
745         return strbuf_detach(&buf, NULL);
746 }
747
748 void append_remote_object_url(struct strbuf *buf, const char *url,
749                               const char *hex,
750                               int only_two_digit_prefix)
751 {
752         end_url_with_slash(buf, url);
753
754         strbuf_addf(buf, "objects/%.*s/", 2, hex);
755         if (!only_two_digit_prefix)
756                 strbuf_addf(buf, "%s", hex+2);
757 }
758
759 char *get_remote_object_url(const char *url, const char *hex,
760                             int only_two_digit_prefix)
761 {
762         struct strbuf buf = STRBUF_INIT;
763         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
764         return strbuf_detach(&buf, NULL);
765 }
766
767 /* http_request() targets */
768 #define HTTP_REQUEST_STRBUF     0
769 #define HTTP_REQUEST_FILE       1
770
771 static int http_request(const char *url, void *result, int target, int options)
772 {
773         struct active_request_slot *slot;
774         struct slot_results results;
775         struct curl_slist *headers = NULL;
776         struct strbuf buf = STRBUF_INIT;
777         int ret;
778
779         slot = get_active_slot();
780         slot->results = &results;
781         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
782
783         if (result == NULL) {
784                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
785         } else {
786                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
787                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
788
789                 if (target == HTTP_REQUEST_FILE) {
790                         long posn = ftell(result);
791                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
792                                          fwrite);
793                         if (posn > 0) {
794                                 strbuf_addf(&buf, "Range: bytes=%ld-", posn);
795                                 headers = curl_slist_append(headers, buf.buf);
796                                 strbuf_reset(&buf);
797                         }
798                         slot->local = result;
799                 } else
800                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
801                                          fwrite_buffer);
802         }
803
804         strbuf_addstr(&buf, "Pragma:");
805         if (options & HTTP_NO_CACHE)
806                 strbuf_addstr(&buf, " no-cache");
807
808         headers = curl_slist_append(headers, buf.buf);
809
810         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
811         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
812
813         if (start_active_slot(slot)) {
814                 run_active_slot(slot);
815                 if (results.curl_result == CURLE_OK)
816                         ret = HTTP_OK;
817                 else if (missing_target(&results))
818                         ret = HTTP_MISSING_TARGET;
819                 else if (results.http_code == 401) {
820                         if (user_name) {
821                                 ret = HTTP_NOAUTH;
822                         } else {
823                                 /*
824                                  * git_getpass is needed here because its very likely stdin/stdout are
825                                  * pipes to our parent process.  So we instead need to use /dev/tty,
826                                  * but that is non-portable.  Using git_getpass() can at least be stubbed
827                                  * on other platforms with a different implementation if/when necessary.
828                                  */
829                                 user_name = xstrdup(git_getpass("Username: "));
830                                 init_curl_http_auth(slot->curl);
831                                 ret = HTTP_REAUTH;
832                         }
833                 } else
834                         ret = HTTP_ERROR;
835         } else {
836                 error("Unable to start HTTP request for %s", url);
837                 ret = HTTP_START_FAILED;
838         }
839
840         slot->local = NULL;
841         curl_slist_free_all(headers);
842         strbuf_release(&buf);
843
844         return ret;
845 }
846
847 int http_get_strbuf(const char *url, struct strbuf *result, int options)
848 {
849         int http_ret = http_request(url, result, HTTP_REQUEST_STRBUF, options);
850         if (http_ret == HTTP_REAUTH) {
851                 http_ret = http_request(url, result, HTTP_REQUEST_STRBUF, options);
852         }
853         return http_ret;
854 }
855
856 /*
857  * Downloads an url and stores the result in the given file.
858  *
859  * If a previous interrupted download is detected (i.e. a previous temporary
860  * file is still around) the download is resumed.
861  */
862 static int http_get_file(const char *url, const char *filename, int options)
863 {
864         int ret;
865         struct strbuf tmpfile = STRBUF_INIT;
866         FILE *result;
867
868         strbuf_addf(&tmpfile, "%s.temp", filename);
869         result = fopen(tmpfile.buf, "a");
870         if (! result) {
871                 error("Unable to open local file %s", tmpfile.buf);
872                 ret = HTTP_ERROR;
873                 goto cleanup;
874         }
875
876         ret = http_request(url, result, HTTP_REQUEST_FILE, options);
877         fclose(result);
878
879         if ((ret == HTTP_OK) && move_temp_to_file(tmpfile.buf, filename))
880                 ret = HTTP_ERROR;
881 cleanup:
882         strbuf_release(&tmpfile);
883         return ret;
884 }
885
886 int http_error(const char *url, int ret)
887 {
888         /* http_request has already handled HTTP_START_FAILED. */
889         if (ret != HTTP_START_FAILED)
890                 error("%s while accessing %s\n", curl_errorstr, url);
891
892         return ret;
893 }
894
895 int http_fetch_ref(const char *base, struct ref *ref)
896 {
897         char *url;
898         struct strbuf buffer = STRBUF_INIT;
899         int ret = -1;
900
901         url = quote_ref_url(base, ref->name);
902         if (http_get_strbuf(url, &buffer, HTTP_NO_CACHE) == HTTP_OK) {
903                 strbuf_rtrim(&buffer);
904                 if (buffer.len == 40)
905                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
906                 else if (!prefixcmp(buffer.buf, "ref: ")) {
907                         ref->symref = xstrdup(buffer.buf + 5);
908                         ret = 0;
909                 }
910         }
911
912         strbuf_release(&buffer);
913         free(url);
914         return ret;
915 }
916
917 /* Helpers for fetching packs */
918 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
919 {
920         char *url, *tmp;
921         struct strbuf buf = STRBUF_INIT;
922
923         if (http_is_verbose)
924                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
925
926         end_url_with_slash(&buf, base_url);
927         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
928         url = strbuf_detach(&buf, NULL);
929
930         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
931         tmp = strbuf_detach(&buf, NULL);
932
933         if (http_get_file(url, tmp, 0) != HTTP_OK) {
934                 error("Unable to get pack index %s\n", url);
935                 free(tmp);
936                 tmp = NULL;
937         }
938
939         free(url);
940         return tmp;
941 }
942
943 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
944         unsigned char *sha1, const char *base_url)
945 {
946         struct packed_git *new_pack;
947         char *tmp_idx = NULL;
948         int ret;
949
950         if (has_pack_index(sha1)) {
951                 new_pack = parse_pack_index(sha1, NULL);
952                 if (!new_pack)
953                         return -1; /* parse_pack_index() already issued error message */
954                 goto add_pack;
955         }
956
957         tmp_idx = fetch_pack_index(sha1, base_url);
958         if (!tmp_idx)
959                 return -1;
960
961         new_pack = parse_pack_index(sha1, tmp_idx);
962         if (!new_pack) {
963                 unlink(tmp_idx);
964                 free(tmp_idx);
965
966                 return -1; /* parse_pack_index() already issued error message */
967         }
968
969         ret = verify_pack_index(new_pack);
970         if (!ret) {
971                 close_pack_index(new_pack);
972                 ret = move_temp_to_file(tmp_idx, sha1_pack_index_name(sha1));
973         }
974         free(tmp_idx);
975         if (ret)
976                 return -1;
977
978 add_pack:
979         new_pack->next = *packs_head;
980         *packs_head = new_pack;
981         return 0;
982 }
983
984 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
985 {
986         int ret = 0, i = 0;
987         char *url, *data;
988         struct strbuf buf = STRBUF_INIT;
989         unsigned char sha1[20];
990
991         end_url_with_slash(&buf, base_url);
992         strbuf_addstr(&buf, "objects/info/packs");
993         url = strbuf_detach(&buf, NULL);
994
995         ret = http_get_strbuf(url, &buf, HTTP_NO_CACHE);
996         if (ret != HTTP_OK)
997                 goto cleanup;
998
999         data = buf.buf;
1000         while (i < buf.len) {
1001                 switch (data[i]) {
1002                 case 'P':
1003                         i++;
1004                         if (i + 52 <= buf.len &&
1005                             !prefixcmp(data + i, " pack-") &&
1006                             !prefixcmp(data + i + 46, ".pack\n")) {
1007                                 get_sha1_hex(data + i + 6, sha1);
1008                                 fetch_and_setup_pack_index(packs_head, sha1,
1009                                                       base_url);
1010                                 i += 51;
1011                                 break;
1012                         }
1013                 default:
1014                         while (i < buf.len && data[i] != '\n')
1015                                 i++;
1016                 }
1017                 i++;
1018         }
1019
1020 cleanup:
1021         free(url);
1022         return ret;
1023 }
1024
1025 void release_http_pack_request(struct http_pack_request *preq)
1026 {
1027         if (preq->packfile != NULL) {
1028                 fclose(preq->packfile);
1029                 preq->packfile = NULL;
1030                 preq->slot->local = NULL;
1031         }
1032         if (preq->range_header != NULL) {
1033                 curl_slist_free_all(preq->range_header);
1034                 preq->range_header = NULL;
1035         }
1036         preq->slot = NULL;
1037         free(preq->url);
1038 }
1039
1040 int finish_http_pack_request(struct http_pack_request *preq)
1041 {
1042         struct packed_git **lst;
1043         struct packed_git *p = preq->target;
1044         char *tmp_idx;
1045         struct child_process ip;
1046         const char *ip_argv[8];
1047
1048         close_pack_index(p);
1049
1050         fclose(preq->packfile);
1051         preq->packfile = NULL;
1052         preq->slot->local = NULL;
1053
1054         lst = preq->lst;
1055         while (*lst != p)
1056                 lst = &((*lst)->next);
1057         *lst = (*lst)->next;
1058
1059         tmp_idx = xstrdup(preq->tmpfile);
1060         strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1061                ".idx.temp");
1062
1063         ip_argv[0] = "index-pack";
1064         ip_argv[1] = "-o";
1065         ip_argv[2] = tmp_idx;
1066         ip_argv[3] = preq->tmpfile;
1067         ip_argv[4] = NULL;
1068
1069         memset(&ip, 0, sizeof(ip));
1070         ip.argv = ip_argv;
1071         ip.git_cmd = 1;
1072         ip.no_stdin = 1;
1073         ip.no_stdout = 1;
1074
1075         if (run_command(&ip)) {
1076                 unlink(preq->tmpfile);
1077                 unlink(tmp_idx);
1078                 free(tmp_idx);
1079                 return -1;
1080         }
1081
1082         unlink(sha1_pack_index_name(p->sha1));
1083
1084         if (move_temp_to_file(preq->tmpfile, sha1_pack_name(p->sha1))
1085          || move_temp_to_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1086                 free(tmp_idx);
1087                 return -1;
1088         }
1089
1090         install_packed_git(p);
1091         free(tmp_idx);
1092         return 0;
1093 }
1094
1095 struct http_pack_request *new_http_pack_request(
1096         struct packed_git *target, const char *base_url)
1097 {
1098         long prev_posn = 0;
1099         char range[RANGE_HEADER_SIZE];
1100         struct strbuf buf = STRBUF_INIT;
1101         struct http_pack_request *preq;
1102
1103         preq = xmalloc(sizeof(*preq));
1104         preq->target = target;
1105         preq->range_header = NULL;
1106
1107         end_url_with_slash(&buf, base_url);
1108         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1109                 sha1_to_hex(target->sha1));
1110         preq->url = strbuf_detach(&buf, NULL);
1111
1112         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1113                 sha1_pack_name(target->sha1));
1114         preq->packfile = fopen(preq->tmpfile, "a");
1115         if (!preq->packfile) {
1116                 error("Unable to open local file %s for pack",
1117                       preq->tmpfile);
1118                 goto abort;
1119         }
1120
1121         preq->slot = get_active_slot();
1122         preq->slot->local = preq->packfile;
1123         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1124         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1125         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1126         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1127                 no_pragma_header);
1128
1129         /*
1130          * If there is data present from a previous transfer attempt,
1131          * resume where it left off
1132          */
1133         prev_posn = ftell(preq->packfile);
1134         if (prev_posn>0) {
1135                 if (http_is_verbose)
1136                         fprintf(stderr,
1137                                 "Resuming fetch of pack %s at byte %ld\n",
1138                                 sha1_to_hex(target->sha1), prev_posn);
1139                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1140                 preq->range_header = curl_slist_append(NULL, range);
1141                 curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1142                         preq->range_header);
1143         }
1144
1145         return preq;
1146
1147 abort:
1148         free(preq->url);
1149         free(preq);
1150         return NULL;
1151 }
1152
1153 /* Helpers for fetching objects (loose) */
1154 static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb,
1155                                void *data)
1156 {
1157         unsigned char expn[4096];
1158         size_t size = eltsize * nmemb;
1159         int posn = 0;
1160         struct http_object_request *freq =
1161                 (struct http_object_request *)data;
1162         do {
1163                 ssize_t retval = xwrite(freq->localfile,
1164                                         (char *) ptr + posn, size - posn);
1165                 if (retval < 0)
1166                         return posn;
1167                 posn += retval;
1168         } while (posn < size);
1169
1170         freq->stream.avail_in = size;
1171         freq->stream.next_in = ptr;
1172         do {
1173                 freq->stream.next_out = expn;
1174                 freq->stream.avail_out = sizeof(expn);
1175                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1176                 git_SHA1_Update(&freq->c, expn,
1177                                 sizeof(expn) - freq->stream.avail_out);
1178         } while (freq->stream.avail_in && freq->zret == Z_OK);
1179         data_received++;
1180         return size;
1181 }
1182
1183 struct http_object_request *new_http_object_request(const char *base_url,
1184         unsigned char *sha1)
1185 {
1186         char *hex = sha1_to_hex(sha1);
1187         char *filename;
1188         char prevfile[PATH_MAX];
1189         int prevlocal;
1190         unsigned char prev_buf[PREV_BUF_SIZE];
1191         ssize_t prev_read = 0;
1192         long prev_posn = 0;
1193         char range[RANGE_HEADER_SIZE];
1194         struct curl_slist *range_header = NULL;
1195         struct http_object_request *freq;
1196
1197         freq = xmalloc(sizeof(*freq));
1198         hashcpy(freq->sha1, sha1);
1199         freq->localfile = -1;
1200
1201         filename = sha1_file_name(sha1);
1202         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1203                  "%s.temp", filename);
1204
1205         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1206         unlink_or_warn(prevfile);
1207         rename(freq->tmpfile, prevfile);
1208         unlink_or_warn(freq->tmpfile);
1209
1210         if (freq->localfile != -1)
1211                 error("fd leakage in start: %d", freq->localfile);
1212         freq->localfile = open(freq->tmpfile,
1213                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1214         /*
1215          * This could have failed due to the "lazy directory creation";
1216          * try to mkdir the last path component.
1217          */
1218         if (freq->localfile < 0 && errno == ENOENT) {
1219                 char *dir = strrchr(freq->tmpfile, '/');
1220                 if (dir) {
1221                         *dir = 0;
1222                         mkdir(freq->tmpfile, 0777);
1223                         *dir = '/';
1224                 }
1225                 freq->localfile = open(freq->tmpfile,
1226                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1227         }
1228
1229         if (freq->localfile < 0) {
1230                 error("Couldn't create temporary file %s: %s",
1231                       freq->tmpfile, strerror(errno));
1232                 goto abort;
1233         }
1234
1235         memset(&freq->stream, 0, sizeof(freq->stream));
1236
1237         git_inflate_init(&freq->stream);
1238
1239         git_SHA1_Init(&freq->c);
1240
1241         freq->url = get_remote_object_url(base_url, hex, 0);
1242
1243         /*
1244          * If a previous temp file is present, process what was already
1245          * fetched.
1246          */
1247         prevlocal = open(prevfile, O_RDONLY);
1248         if (prevlocal != -1) {
1249                 do {
1250                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1251                         if (prev_read>0) {
1252                                 if (fwrite_sha1_file(prev_buf,
1253                                                      1,
1254                                                      prev_read,
1255                                                      freq) == prev_read) {
1256                                         prev_posn += prev_read;
1257                                 } else {
1258                                         prev_read = -1;
1259                                 }
1260                         }
1261                 } while (prev_read > 0);
1262                 close(prevlocal);
1263         }
1264         unlink_or_warn(prevfile);
1265
1266         /*
1267          * Reset inflate/SHA1 if there was an error reading the previous temp
1268          * file; also rewind to the beginning of the local file.
1269          */
1270         if (prev_read == -1) {
1271                 memset(&freq->stream, 0, sizeof(freq->stream));
1272                 git_inflate_init(&freq->stream);
1273                 git_SHA1_Init(&freq->c);
1274                 if (prev_posn>0) {
1275                         prev_posn = 0;
1276                         lseek(freq->localfile, 0, SEEK_SET);
1277                         if (ftruncate(freq->localfile, 0) < 0) {
1278                                 error("Couldn't truncate temporary file %s: %s",
1279                                           freq->tmpfile, strerror(errno));
1280                                 goto abort;
1281                         }
1282                 }
1283         }
1284
1285         freq->slot = get_active_slot();
1286
1287         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1288         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1289         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1290         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1291         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1292
1293         /*
1294          * If we have successfully processed data from a previous fetch
1295          * attempt, only fetch the data we don't already have.
1296          */
1297         if (prev_posn>0) {
1298                 if (http_is_verbose)
1299                         fprintf(stderr,
1300                                 "Resuming fetch of object %s at byte %ld\n",
1301                                 hex, prev_posn);
1302                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1303                 range_header = curl_slist_append(range_header, range);
1304                 curl_easy_setopt(freq->slot->curl,
1305                                  CURLOPT_HTTPHEADER, range_header);
1306         }
1307
1308         return freq;
1309
1310 abort:
1311         free(filename);
1312         free(freq->url);
1313         free(freq);
1314         return NULL;
1315 }
1316
1317 void process_http_object_request(struct http_object_request *freq)
1318 {
1319         if (freq->slot == NULL)
1320                 return;
1321         freq->curl_result = freq->slot->curl_result;
1322         freq->http_code = freq->slot->http_code;
1323         freq->slot = NULL;
1324 }
1325
1326 int finish_http_object_request(struct http_object_request *freq)
1327 {
1328         struct stat st;
1329
1330         close(freq->localfile);
1331         freq->localfile = -1;
1332
1333         process_http_object_request(freq);
1334
1335         if (freq->http_code == 416) {
1336                 warning("requested range invalid; we may already have all the data.");
1337         } else if (freq->curl_result != CURLE_OK) {
1338                 if (stat(freq->tmpfile, &st) == 0)
1339                         if (st.st_size == 0)
1340                                 unlink_or_warn(freq->tmpfile);
1341                 return -1;
1342         }
1343
1344         git_inflate_end(&freq->stream);
1345         git_SHA1_Final(freq->real_sha1, &freq->c);
1346         if (freq->zret != Z_STREAM_END) {
1347                 unlink_or_warn(freq->tmpfile);
1348                 return -1;
1349         }
1350         if (hashcmp(freq->sha1, freq->real_sha1)) {
1351                 unlink_or_warn(freq->tmpfile);
1352                 return -1;
1353         }
1354         freq->rename =
1355                 move_temp_to_file(freq->tmpfile, sha1_file_name(freq->sha1));
1356
1357         return freq->rename;
1358 }
1359
1360 void abort_http_object_request(struct http_object_request *freq)
1361 {
1362         unlink_or_warn(freq->tmpfile);
1363
1364         release_http_object_request(freq);
1365 }
1366
1367 void release_http_object_request(struct http_object_request *freq)
1368 {
1369         if (freq->localfile != -1) {
1370                 close(freq->localfile);
1371                 freq->localfile = -1;
1372         }
1373         if (freq->url != NULL) {
1374                 free(freq->url);
1375                 freq->url = NULL;
1376         }
1377         if (freq->slot != NULL) {
1378                 freq->slot->callback_func = NULL;
1379                 freq->slot->callback_data = NULL;
1380                 release_active_slot(freq->slot);
1381                 freq->slot = NULL;
1382         }
1383 }