packfile-uri.txt: fix blobPackfileUri description
[git] / http.c
1 #include "git-compat-util.h"
2 #include "http.h"
3 #include "config.h"
4 #include "pack.h"
5 #include "sideband.h"
6 #include "run-command.h"
7 #include "url.h"
8 #include "urlmatch.h"
9 #include "credential.h"
10 #include "version.h"
11 #include "pkt-line.h"
12 #include "gettext.h"
13 #include "transport.h"
14 #include "packfile.h"
15 #include "protocol.h"
16 #include "string-list.h"
17 #include "object-store.h"
18
19 static struct trace_key trace_curl = TRACE_KEY_INIT(CURL);
20 static int trace_curl_data = 1;
21 static int trace_curl_redact = 1;
22 #if LIBCURL_VERSION_NUM >= 0x070a08
23 long int git_curl_ipresolve = CURL_IPRESOLVE_WHATEVER;
24 #else
25 long int git_curl_ipresolve;
26 #endif
27 int active_requests;
28 int http_is_verbose;
29 ssize_t http_post_buffer = 16 * LARGE_PACKET_MAX;
30
31 #if LIBCURL_VERSION_NUM >= 0x070a06
32 #define LIBCURL_CAN_HANDLE_AUTH_ANY
33 #endif
34
35 static int min_curl_sessions = 1;
36 static int curl_session_count;
37 #ifdef USE_CURL_MULTI
38 static int max_requests = -1;
39 static CURLM *curlm;
40 #endif
41 #ifndef NO_CURL_EASY_DUPHANDLE
42 static CURL *curl_default;
43 #endif
44
45 #define PREV_BUF_SIZE 4096
46
47 char curl_errorstr[CURL_ERROR_SIZE];
48
49 static int curl_ssl_verify = -1;
50 static int curl_ssl_try;
51 static const char *curl_http_version = NULL;
52 static const char *ssl_cert;
53 static const char *ssl_cipherlist;
54 static const char *ssl_version;
55 static struct {
56         const char *name;
57         long ssl_version;
58 } sslversions[] = {
59         { "sslv2", CURL_SSLVERSION_SSLv2 },
60         { "sslv3", CURL_SSLVERSION_SSLv3 },
61         { "tlsv1", CURL_SSLVERSION_TLSv1 },
62 #if LIBCURL_VERSION_NUM >= 0x072200
63         { "tlsv1.0", CURL_SSLVERSION_TLSv1_0 },
64         { "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
65         { "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
66 #endif
67 #if LIBCURL_VERSION_NUM >= 0x073400
68         { "tlsv1.3", CURL_SSLVERSION_TLSv1_3 },
69 #endif
70 };
71 #if LIBCURL_VERSION_NUM >= 0x070903
72 static const char *ssl_key;
73 #endif
74 #if LIBCURL_VERSION_NUM >= 0x070908
75 static const char *ssl_capath;
76 #endif
77 #if LIBCURL_VERSION_NUM >= 0x071304
78 static const char *curl_no_proxy;
79 #endif
80 #if LIBCURL_VERSION_NUM >= 0x072c00
81 static const char *ssl_pinnedkey;
82 #endif
83 static const char *ssl_cainfo;
84 static long curl_low_speed_limit = -1;
85 static long curl_low_speed_time = -1;
86 static int curl_ftp_no_epsv;
87 static const char *curl_http_proxy;
88 static const char *http_proxy_authmethod;
89
90 static const char *http_proxy_ssl_cert;
91 static const char *http_proxy_ssl_key;
92 static const char *http_proxy_ssl_ca_info;
93 static struct credential proxy_cert_auth = CREDENTIAL_INIT;
94 static int proxy_ssl_cert_password_required;
95
96 static struct {
97         const char *name;
98         long curlauth_param;
99 } proxy_authmethods[] = {
100         { "basic", CURLAUTH_BASIC },
101         { "digest", CURLAUTH_DIGEST },
102         { "negotiate", CURLAUTH_GSSNEGOTIATE },
103         { "ntlm", CURLAUTH_NTLM },
104 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
105         { "anyauth", CURLAUTH_ANY },
106 #endif
107         /*
108          * CURLAUTH_DIGEST_IE has no corresponding command-line option in
109          * curl(1) and is not included in CURLAUTH_ANY, so we leave it out
110          * here, too
111          */
112 };
113 #ifdef CURLGSSAPI_DELEGATION_FLAG
114 static const char *curl_deleg;
115 static struct {
116         const char *name;
117         long curl_deleg_param;
118 } curl_deleg_levels[] = {
119         { "none", CURLGSSAPI_DELEGATION_NONE },
120         { "policy", CURLGSSAPI_DELEGATION_POLICY_FLAG },
121         { "always", CURLGSSAPI_DELEGATION_FLAG },
122 };
123 #endif
124
125 static struct credential proxy_auth = CREDENTIAL_INIT;
126 static const char *curl_proxyuserpwd;
127 static const char *curl_cookie_file;
128 static int curl_save_cookies;
129 struct credential http_auth = CREDENTIAL_INIT;
130 static int http_proactive_auth;
131 static const char *user_agent;
132 static int curl_empty_auth = -1;
133
134 enum http_follow_config http_follow_config = HTTP_FOLLOW_INITIAL;
135
136 #if LIBCURL_VERSION_NUM >= 0x071700
137 /* Use CURLOPT_KEYPASSWD as is */
138 #elif LIBCURL_VERSION_NUM >= 0x070903
139 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
140 #else
141 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
142 #endif
143
144 static struct credential cert_auth = CREDENTIAL_INIT;
145 static int ssl_cert_password_required;
146 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
147 static unsigned long http_auth_methods = CURLAUTH_ANY;
148 static int http_auth_methods_restricted;
149 /* Modes for which empty_auth cannot actually help us. */
150 static unsigned long empty_auth_useless =
151         CURLAUTH_BASIC
152 #ifdef CURLAUTH_DIGEST_IE
153         | CURLAUTH_DIGEST_IE
154 #endif
155         | CURLAUTH_DIGEST;
156 #endif
157
158 static struct curl_slist *pragma_header;
159 static struct curl_slist *no_pragma_header;
160 static struct string_list extra_http_headers = STRING_LIST_INIT_DUP;
161
162 static struct active_request_slot *active_queue_head;
163
164 static char *cached_accept_language;
165
166 static char *http_ssl_backend;
167
168 static int http_schannel_check_revoke = 1;
169 /*
170  * With the backend being set to `schannel`, setting sslCAinfo would override
171  * the Certificate Store in cURL v7.60.0 and later, which is not what we want
172  * by default.
173  */
174 static int http_schannel_use_ssl_cainfo;
175
176 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
177 {
178         size_t size = eltsize * nmemb;
179         struct buffer *buffer = buffer_;
180
181         if (size > buffer->buf.len - buffer->posn)
182                 size = buffer->buf.len - buffer->posn;
183         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
184         buffer->posn += size;
185
186         return size / eltsize;
187 }
188
189 #ifndef NO_CURL_IOCTL
190 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
191 {
192         struct buffer *buffer = clientp;
193
194         switch (cmd) {
195         case CURLIOCMD_NOP:
196                 return CURLIOE_OK;
197
198         case CURLIOCMD_RESTARTREAD:
199                 buffer->posn = 0;
200                 return CURLIOE_OK;
201
202         default:
203                 return CURLIOE_UNKNOWNCMD;
204         }
205 }
206 #endif
207
208 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
209 {
210         size_t size = eltsize * nmemb;
211         struct strbuf *buffer = buffer_;
212
213         strbuf_add(buffer, ptr, size);
214         return nmemb;
215 }
216
217 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
218 {
219         return nmemb;
220 }
221
222 static void closedown_active_slot(struct active_request_slot *slot)
223 {
224         active_requests--;
225         slot->in_use = 0;
226 }
227
228 static void finish_active_slot(struct active_request_slot *slot)
229 {
230         closedown_active_slot(slot);
231         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
232
233         if (slot->finished != NULL)
234                 (*slot->finished) = 1;
235
236         /* Store slot results so they can be read after the slot is reused */
237         if (slot->results != NULL) {
238                 slot->results->curl_result = slot->curl_result;
239                 slot->results->http_code = slot->http_code;
240 #if LIBCURL_VERSION_NUM >= 0x070a08
241                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
242                                   &slot->results->auth_avail);
243 #else
244                 slot->results->auth_avail = 0;
245 #endif
246
247                 curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CONNECTCODE,
248                         &slot->results->http_connectcode);
249         }
250
251         /* Run callback if appropriate */
252         if (slot->callback_func != NULL)
253                 slot->callback_func(slot->callback_data);
254 }
255
256 static void xmulti_remove_handle(struct active_request_slot *slot)
257 {
258 #ifdef USE_CURL_MULTI
259         curl_multi_remove_handle(curlm, slot->curl);
260 #endif
261 }
262
263 #ifdef USE_CURL_MULTI
264 static void process_curl_messages(void)
265 {
266         int num_messages;
267         struct active_request_slot *slot;
268         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
269
270         while (curl_message != NULL) {
271                 if (curl_message->msg == CURLMSG_DONE) {
272                         int curl_result = curl_message->data.result;
273                         slot = active_queue_head;
274                         while (slot != NULL &&
275                                slot->curl != curl_message->easy_handle)
276                                 slot = slot->next;
277                         if (slot != NULL) {
278                                 xmulti_remove_handle(slot);
279                                 slot->curl_result = curl_result;
280                                 finish_active_slot(slot);
281                         } else {
282                                 fprintf(stderr, "Received DONE message for unknown request!\n");
283                         }
284                 } else {
285                         fprintf(stderr, "Unknown CURL message received: %d\n",
286                                 (int)curl_message->msg);
287                 }
288                 curl_message = curl_multi_info_read(curlm, &num_messages);
289         }
290 }
291 #endif
292
293 static int http_options(const char *var, const char *value, void *cb)
294 {
295         if (!strcmp("http.version", var)) {
296                 return git_config_string(&curl_http_version, var, value);
297         }
298         if (!strcmp("http.sslverify", var)) {
299                 curl_ssl_verify = git_config_bool(var, value);
300                 return 0;
301         }
302         if (!strcmp("http.sslcipherlist", var))
303                 return git_config_string(&ssl_cipherlist, var, value);
304         if (!strcmp("http.sslversion", var))
305                 return git_config_string(&ssl_version, var, value);
306         if (!strcmp("http.sslcert", var))
307                 return git_config_pathname(&ssl_cert, var, value);
308 #if LIBCURL_VERSION_NUM >= 0x070903
309         if (!strcmp("http.sslkey", var))
310                 return git_config_pathname(&ssl_key, var, value);
311 #endif
312 #if LIBCURL_VERSION_NUM >= 0x070908
313         if (!strcmp("http.sslcapath", var))
314                 return git_config_pathname(&ssl_capath, var, value);
315 #endif
316         if (!strcmp("http.sslcainfo", var))
317                 return git_config_pathname(&ssl_cainfo, var, value);
318         if (!strcmp("http.sslcertpasswordprotected", var)) {
319                 ssl_cert_password_required = git_config_bool(var, value);
320                 return 0;
321         }
322         if (!strcmp("http.ssltry", var)) {
323                 curl_ssl_try = git_config_bool(var, value);
324                 return 0;
325         }
326         if (!strcmp("http.sslbackend", var)) {
327                 free(http_ssl_backend);
328                 http_ssl_backend = xstrdup_or_null(value);
329                 return 0;
330         }
331
332         if (!strcmp("http.schannelcheckrevoke", var)) {
333                 http_schannel_check_revoke = git_config_bool(var, value);
334                 return 0;
335         }
336
337         if (!strcmp("http.schannelusesslcainfo", var)) {
338                 http_schannel_use_ssl_cainfo = git_config_bool(var, value);
339                 return 0;
340         }
341
342         if (!strcmp("http.minsessions", var)) {
343                 min_curl_sessions = git_config_int(var, value);
344 #ifndef USE_CURL_MULTI
345                 if (min_curl_sessions > 1)
346                         min_curl_sessions = 1;
347 #endif
348                 return 0;
349         }
350 #ifdef USE_CURL_MULTI
351         if (!strcmp("http.maxrequests", var)) {
352                 max_requests = git_config_int(var, value);
353                 return 0;
354         }
355 #endif
356         if (!strcmp("http.lowspeedlimit", var)) {
357                 curl_low_speed_limit = (long)git_config_int(var, value);
358                 return 0;
359         }
360         if (!strcmp("http.lowspeedtime", var)) {
361                 curl_low_speed_time = (long)git_config_int(var, value);
362                 return 0;
363         }
364
365         if (!strcmp("http.noepsv", var)) {
366                 curl_ftp_no_epsv = git_config_bool(var, value);
367                 return 0;
368         }
369         if (!strcmp("http.proxy", var))
370                 return git_config_string(&curl_http_proxy, var, value);
371
372         if (!strcmp("http.proxyauthmethod", var))
373                 return git_config_string(&http_proxy_authmethod, var, value);
374
375         if (!strcmp("http.proxysslcert", var))
376                 return git_config_string(&http_proxy_ssl_cert, var, value);
377
378         if (!strcmp("http.proxysslkey", var))
379                 return git_config_string(&http_proxy_ssl_key, var, value);
380
381         if (!strcmp("http.proxysslcainfo", var))
382                 return git_config_string(&http_proxy_ssl_ca_info, var, value);
383
384         if (!strcmp("http.proxysslcertpasswordprotected", var)) {
385                 proxy_ssl_cert_password_required = git_config_bool(var, value);
386                 return 0;
387         }
388
389         if (!strcmp("http.cookiefile", var))
390                 return git_config_pathname(&curl_cookie_file, var, value);
391         if (!strcmp("http.savecookies", var)) {
392                 curl_save_cookies = git_config_bool(var, value);
393                 return 0;
394         }
395
396         if (!strcmp("http.postbuffer", var)) {
397                 http_post_buffer = git_config_ssize_t(var, value);
398                 if (http_post_buffer < 0)
399                         warning(_("negative value for http.postbuffer; defaulting to %d"), LARGE_PACKET_MAX);
400                 if (http_post_buffer < LARGE_PACKET_MAX)
401                         http_post_buffer = LARGE_PACKET_MAX;
402                 return 0;
403         }
404
405         if (!strcmp("http.useragent", var))
406                 return git_config_string(&user_agent, var, value);
407
408         if (!strcmp("http.emptyauth", var)) {
409                 if (value && !strcmp("auto", value))
410                         curl_empty_auth = -1;
411                 else
412                         curl_empty_auth = git_config_bool(var, value);
413                 return 0;
414         }
415
416         if (!strcmp("http.delegation", var)) {
417 #ifdef CURLGSSAPI_DELEGATION_FLAG
418                 return git_config_string(&curl_deleg, var, value);
419 #else
420                 warning(_("Delegation control is not supported with cURL < 7.22.0"));
421                 return 0;
422 #endif
423         }
424
425         if (!strcmp("http.pinnedpubkey", var)) {
426 #if LIBCURL_VERSION_NUM >= 0x072c00
427                 return git_config_pathname(&ssl_pinnedkey, var, value);
428 #else
429                 warning(_("Public key pinning not supported with cURL < 7.44.0"));
430                 return 0;
431 #endif
432         }
433
434         if (!strcmp("http.extraheader", var)) {
435                 if (!value) {
436                         return config_error_nonbool(var);
437                 } else if (!*value) {
438                         string_list_clear(&extra_http_headers, 0);
439                 } else {
440                         string_list_append(&extra_http_headers, value);
441                 }
442                 return 0;
443         }
444
445         if (!strcmp("http.followredirects", var)) {
446                 if (value && !strcmp(value, "initial"))
447                         http_follow_config = HTTP_FOLLOW_INITIAL;
448                 else if (git_config_bool(var, value))
449                         http_follow_config = HTTP_FOLLOW_ALWAYS;
450                 else
451                         http_follow_config = HTTP_FOLLOW_NONE;
452                 return 0;
453         }
454
455         /* Fall back on the default ones */
456         return git_default_config(var, value, cb);
457 }
458
459 static int curl_empty_auth_enabled(void)
460 {
461         if (curl_empty_auth >= 0)
462                 return curl_empty_auth;
463
464 #ifndef LIBCURL_CAN_HANDLE_AUTH_ANY
465         /*
466          * Our libcurl is too old to do AUTH_ANY in the first place;
467          * just default to turning the feature off.
468          */
469 #else
470         /*
471          * In the automatic case, kick in the empty-auth
472          * hack as long as we would potentially try some
473          * method more exotic than "Basic" or "Digest".
474          *
475          * But only do this when this is our second or
476          * subsequent request, as by then we know what
477          * methods are available.
478          */
479         if (http_auth_methods_restricted &&
480             (http_auth_methods & ~empty_auth_useless))
481                 return 1;
482 #endif
483         return 0;
484 }
485
486 static void init_curl_http_auth(CURL *result)
487 {
488         if (!http_auth.username || !*http_auth.username) {
489                 if (curl_empty_auth_enabled())
490                         curl_easy_setopt(result, CURLOPT_USERPWD, ":");
491                 return;
492         }
493
494         credential_fill(&http_auth);
495
496 #if LIBCURL_VERSION_NUM >= 0x071301
497         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
498         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
499 #else
500         {
501                 static struct strbuf up = STRBUF_INIT;
502                 /*
503                  * Note that we assume we only ever have a single set of
504                  * credentials in a given program run, so we do not have
505                  * to worry about updating this buffer, only setting its
506                  * initial value.
507                  */
508                 if (!up.len)
509                         strbuf_addf(&up, "%s:%s",
510                                 http_auth.username, http_auth.password);
511                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
512         }
513 #endif
514 }
515
516 /* *var must be free-able */
517 static void var_override(const char **var, char *value)
518 {
519         if (value) {
520                 free((void *)*var);
521                 *var = xstrdup(value);
522         }
523 }
524
525 static void set_proxyauth_name_password(CURL *result)
526 {
527 #if LIBCURL_VERSION_NUM >= 0x071301
528                 curl_easy_setopt(result, CURLOPT_PROXYUSERNAME,
529                         proxy_auth.username);
530                 curl_easy_setopt(result, CURLOPT_PROXYPASSWORD,
531                         proxy_auth.password);
532 #else
533                 struct strbuf s = STRBUF_INIT;
534
535                 strbuf_addstr_urlencode(&s, proxy_auth.username,
536                                         is_rfc3986_unreserved);
537                 strbuf_addch(&s, ':');
538                 strbuf_addstr_urlencode(&s, proxy_auth.password,
539                                         is_rfc3986_unreserved);
540                 curl_proxyuserpwd = strbuf_detach(&s, NULL);
541                 curl_easy_setopt(result, CURLOPT_PROXYUSERPWD, curl_proxyuserpwd);
542 #endif
543 }
544
545 static void init_curl_proxy_auth(CURL *result)
546 {
547         if (proxy_auth.username) {
548                 if (!proxy_auth.password)
549                         credential_fill(&proxy_auth);
550                 set_proxyauth_name_password(result);
551         }
552
553         var_override(&http_proxy_authmethod, getenv("GIT_HTTP_PROXY_AUTHMETHOD"));
554
555 #if LIBCURL_VERSION_NUM >= 0x070a07 /* CURLOPT_PROXYAUTH and CURLAUTH_ANY */
556         if (http_proxy_authmethod) {
557                 int i;
558                 for (i = 0; i < ARRAY_SIZE(proxy_authmethods); i++) {
559                         if (!strcmp(http_proxy_authmethod, proxy_authmethods[i].name)) {
560                                 curl_easy_setopt(result, CURLOPT_PROXYAUTH,
561                                                 proxy_authmethods[i].curlauth_param);
562                                 break;
563                         }
564                 }
565                 if (i == ARRAY_SIZE(proxy_authmethods)) {
566                         warning("unsupported proxy authentication method %s: using anyauth",
567                                         http_proxy_authmethod);
568                         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
569                 }
570         }
571         else
572                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
573 #endif
574 }
575
576 static int has_cert_password(void)
577 {
578         if (ssl_cert == NULL || ssl_cert_password_required != 1)
579                 return 0;
580         if (!cert_auth.password) {
581                 cert_auth.protocol = xstrdup("cert");
582                 cert_auth.host = xstrdup("");
583                 cert_auth.username = xstrdup("");
584                 cert_auth.path = xstrdup(ssl_cert);
585                 credential_fill(&cert_auth);
586         }
587         return 1;
588 }
589
590 #if LIBCURL_VERSION_NUM >= 0x073400
591 static int has_proxy_cert_password(void)
592 {
593         if (http_proxy_ssl_cert == NULL || proxy_ssl_cert_password_required != 1)
594                 return 0;
595         if (!proxy_cert_auth.password) {
596                 proxy_cert_auth.protocol = xstrdup("cert");
597                 proxy_cert_auth.host = xstrdup("");
598                 proxy_cert_auth.username = xstrdup("");
599                 proxy_cert_auth.path = xstrdup(http_proxy_ssl_cert);
600                 credential_fill(&proxy_cert_auth);
601         }
602         return 1;
603 }
604 #endif
605
606 #if LIBCURL_VERSION_NUM >= 0x071900
607 static void set_curl_keepalive(CURL *c)
608 {
609         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
610 }
611
612 #elif LIBCURL_VERSION_NUM >= 0x071000
613 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
614 {
615         int ka = 1;
616         int rc;
617         socklen_t len = (socklen_t)sizeof(ka);
618
619         if (type != CURLSOCKTYPE_IPCXN)
620                 return 0;
621
622         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
623         if (rc < 0)
624                 warning_errno("unable to set SO_KEEPALIVE on socket");
625
626         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
627 }
628
629 static void set_curl_keepalive(CURL *c)
630 {
631         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
632 }
633
634 #else
635 static void set_curl_keepalive(CURL *c)
636 {
637         /* not supported on older curl versions */
638 }
639 #endif
640
641 static void redact_sensitive_header(struct strbuf *header)
642 {
643         const char *sensitive_header;
644
645         if (trace_curl_redact &&
646             (skip_prefix(header->buf, "Authorization:", &sensitive_header) ||
647              skip_prefix(header->buf, "Proxy-Authorization:", &sensitive_header))) {
648                 /* The first token is the type, which is OK to log */
649                 while (isspace(*sensitive_header))
650                         sensitive_header++;
651                 while (*sensitive_header && !isspace(*sensitive_header))
652                         sensitive_header++;
653                 /* Everything else is opaque and possibly sensitive */
654                 strbuf_setlen(header,  sensitive_header - header->buf);
655                 strbuf_addstr(header, " <redacted>");
656         } else if (trace_curl_redact &&
657                    skip_prefix(header->buf, "Cookie:", &sensitive_header)) {
658                 struct strbuf redacted_header = STRBUF_INIT;
659                 const char *cookie;
660
661                 while (isspace(*sensitive_header))
662                         sensitive_header++;
663
664                 cookie = sensitive_header;
665
666                 while (cookie) {
667                         char *equals;
668                         char *semicolon = strstr(cookie, "; ");
669                         if (semicolon)
670                                 *semicolon = 0;
671                         equals = strchrnul(cookie, '=');
672                         if (!equals) {
673                                 /* invalid cookie, just append and continue */
674                                 strbuf_addstr(&redacted_header, cookie);
675                                 continue;
676                         }
677                         strbuf_add(&redacted_header, cookie, equals - cookie);
678                         strbuf_addstr(&redacted_header, "=<redacted>");
679                         if (semicolon) {
680                                 /*
681                                  * There are more cookies. (Or, for some
682                                  * reason, the input string ends in "; ".)
683                                  */
684                                 strbuf_addstr(&redacted_header, "; ");
685                                 cookie = semicolon + strlen("; ");
686                         } else {
687                                 cookie = NULL;
688                         }
689                 }
690
691                 strbuf_setlen(header, sensitive_header - header->buf);
692                 strbuf_addbuf(header, &redacted_header);
693         }
694 }
695
696 static void curl_dump_header(const char *text, unsigned char *ptr, size_t size, int hide_sensitive_header)
697 {
698         struct strbuf out = STRBUF_INIT;
699         struct strbuf **headers, **header;
700
701         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
702                 text, (long)size, (long)size);
703         trace_strbuf(&trace_curl, &out);
704         strbuf_reset(&out);
705         strbuf_add(&out, ptr, size);
706         headers = strbuf_split_max(&out, '\n', 0);
707
708         for (header = headers; *header; header++) {
709                 if (hide_sensitive_header)
710                         redact_sensitive_header(*header);
711                 strbuf_insertstr((*header), 0, text);
712                 strbuf_insertstr((*header), strlen(text), ": ");
713                 strbuf_rtrim((*header));
714                 strbuf_addch((*header), '\n');
715                 trace_strbuf(&trace_curl, (*header));
716         }
717         strbuf_list_free(headers);
718         strbuf_release(&out);
719 }
720
721 static void curl_dump_data(const char *text, unsigned char *ptr, size_t size)
722 {
723         size_t i;
724         struct strbuf out = STRBUF_INIT;
725         unsigned int width = 60;
726
727         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
728                 text, (long)size, (long)size);
729         trace_strbuf(&trace_curl, &out);
730
731         for (i = 0; i < size; i += width) {
732                 size_t w;
733
734                 strbuf_reset(&out);
735                 strbuf_addf(&out, "%s: ", text);
736                 for (w = 0; (w < width) && (i + w < size); w++) {
737                         unsigned char ch = ptr[i + w];
738
739                         strbuf_addch(&out,
740                                        (ch >= 0x20) && (ch < 0x80)
741                                        ? ch : '.');
742                 }
743                 strbuf_addch(&out, '\n');
744                 trace_strbuf(&trace_curl, &out);
745         }
746         strbuf_release(&out);
747 }
748
749 static int curl_trace(CURL *handle, curl_infotype type, char *data, size_t size, void *userp)
750 {
751         const char *text;
752         enum { NO_FILTER = 0, DO_FILTER = 1 };
753
754         switch (type) {
755         case CURLINFO_TEXT:
756                 trace_printf_key(&trace_curl, "== Info: %s", data);
757                 break;
758         case CURLINFO_HEADER_OUT:
759                 text = "=> Send header";
760                 curl_dump_header(text, (unsigned char *)data, size, DO_FILTER);
761                 break;
762         case CURLINFO_DATA_OUT:
763                 if (trace_curl_data) {
764                         text = "=> Send data";
765                         curl_dump_data(text, (unsigned char *)data, size);
766                 }
767                 break;
768         case CURLINFO_SSL_DATA_OUT:
769                 if (trace_curl_data) {
770                         text = "=> Send SSL data";
771                         curl_dump_data(text, (unsigned char *)data, size);
772                 }
773                 break;
774         case CURLINFO_HEADER_IN:
775                 text = "<= Recv header";
776                 curl_dump_header(text, (unsigned char *)data, size, NO_FILTER);
777                 break;
778         case CURLINFO_DATA_IN:
779                 if (trace_curl_data) {
780                         text = "<= Recv data";
781                         curl_dump_data(text, (unsigned char *)data, size);
782                 }
783                 break;
784         case CURLINFO_SSL_DATA_IN:
785                 if (trace_curl_data) {
786                         text = "<= Recv SSL data";
787                         curl_dump_data(text, (unsigned char *)data, size);
788                 }
789                 break;
790
791         default:                /* we ignore unknown types by default */
792                 return 0;
793         }
794         return 0;
795 }
796
797 void http_trace_curl_no_data(void)
798 {
799         trace_override_envvar(&trace_curl, "1");
800         trace_curl_data = 0;
801 }
802
803 void setup_curl_trace(CURL *handle)
804 {
805         if (!trace_want(&trace_curl))
806                 return;
807         curl_easy_setopt(handle, CURLOPT_VERBOSE, 1L);
808         curl_easy_setopt(handle, CURLOPT_DEBUGFUNCTION, curl_trace);
809         curl_easy_setopt(handle, CURLOPT_DEBUGDATA, NULL);
810 }
811
812 #ifdef CURLPROTO_HTTP
813 static long get_curl_allowed_protocols(int from_user)
814 {
815         long allowed_protocols = 0;
816
817         if (is_transport_allowed("http", from_user))
818                 allowed_protocols |= CURLPROTO_HTTP;
819         if (is_transport_allowed("https", from_user))
820                 allowed_protocols |= CURLPROTO_HTTPS;
821         if (is_transport_allowed("ftp", from_user))
822                 allowed_protocols |= CURLPROTO_FTP;
823         if (is_transport_allowed("ftps", from_user))
824                 allowed_protocols |= CURLPROTO_FTPS;
825
826         return allowed_protocols;
827 }
828 #endif
829
830 #if LIBCURL_VERSION_NUM >=0x072f00
831 static int get_curl_http_version_opt(const char *version_string, long *opt)
832 {
833         int i;
834         static struct {
835                 const char *name;
836                 long opt_token;
837         } choice[] = {
838                 { "HTTP/1.1", CURL_HTTP_VERSION_1_1 },
839                 { "HTTP/2", CURL_HTTP_VERSION_2 }
840         };
841
842         for (i = 0; i < ARRAY_SIZE(choice); i++) {
843                 if (!strcmp(version_string, choice[i].name)) {
844                         *opt = choice[i].opt_token;
845                         return 0;
846                 }
847         }
848
849         warning("unknown value given to http.version: '%s'", version_string);
850         return -1; /* not found */
851 }
852
853 #endif
854
855 static CURL *get_curl_handle(void)
856 {
857         CURL *result = curl_easy_init();
858
859         if (!result)
860                 die("curl_easy_init failed");
861
862         if (!curl_ssl_verify) {
863                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
864                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
865         } else {
866                 /* Verify authenticity of the peer's certificate */
867                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
868                 /* The name in the cert must match whom we tried to connect */
869                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
870         }
871
872 #if LIBCURL_VERSION_NUM >= 0x072f00 // 7.47.0
873     if (curl_http_version) {
874                 long opt;
875                 if (!get_curl_http_version_opt(curl_http_version, &opt)) {
876                         /* Set request use http version */
877                         curl_easy_setopt(result, CURLOPT_HTTP_VERSION, opt);
878                 }
879     }
880 #endif
881
882 #if LIBCURL_VERSION_NUM >= 0x070907
883         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
884 #endif
885 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
886         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
887 #endif
888
889 #ifdef CURLGSSAPI_DELEGATION_FLAG
890         if (curl_deleg) {
891                 int i;
892                 for (i = 0; i < ARRAY_SIZE(curl_deleg_levels); i++) {
893                         if (!strcmp(curl_deleg, curl_deleg_levels[i].name)) {
894                                 curl_easy_setopt(result, CURLOPT_GSSAPI_DELEGATION,
895                                                 curl_deleg_levels[i].curl_deleg_param);
896                                 break;
897                         }
898                 }
899                 if (i == ARRAY_SIZE(curl_deleg_levels))
900                         warning("Unknown delegation method '%s': using default",
901                                 curl_deleg);
902         }
903 #endif
904
905         if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
906             !http_schannel_check_revoke) {
907 #if LIBCURL_VERSION_NUM >= 0x072c00
908                 curl_easy_setopt(result, CURLOPT_SSL_OPTIONS, CURLSSLOPT_NO_REVOKE);
909 #else
910                 warning(_("CURLSSLOPT_NO_REVOKE not supported with cURL < 7.44.0"));
911 #endif
912         }
913
914         if (http_proactive_auth)
915                 init_curl_http_auth(result);
916
917         if (getenv("GIT_SSL_VERSION"))
918                 ssl_version = getenv("GIT_SSL_VERSION");
919         if (ssl_version && *ssl_version) {
920                 int i;
921                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
922                         if (!strcmp(ssl_version, sslversions[i].name)) {
923                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
924                                                  sslversions[i].ssl_version);
925                                 break;
926                         }
927                 }
928                 if (i == ARRAY_SIZE(sslversions))
929                         warning("unsupported ssl version %s: using default",
930                                 ssl_version);
931         }
932
933         if (getenv("GIT_SSL_CIPHER_LIST"))
934                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
935         if (ssl_cipherlist != NULL && *ssl_cipherlist)
936                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
937                                 ssl_cipherlist);
938
939         if (ssl_cert != NULL)
940                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
941         if (has_cert_password())
942                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
943 #if LIBCURL_VERSION_NUM >= 0x070903
944         if (ssl_key != NULL)
945                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
946 #endif
947 #if LIBCURL_VERSION_NUM >= 0x070908
948         if (ssl_capath != NULL)
949                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
950 #endif
951 #if LIBCURL_VERSION_NUM >= 0x072c00
952         if (ssl_pinnedkey != NULL)
953                 curl_easy_setopt(result, CURLOPT_PINNEDPUBLICKEY, ssl_pinnedkey);
954 #endif
955         if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
956             !http_schannel_use_ssl_cainfo) {
957                 curl_easy_setopt(result, CURLOPT_CAINFO, NULL);
958 #if LIBCURL_VERSION_NUM >= 0x073400
959                 curl_easy_setopt(result, CURLOPT_PROXY_CAINFO, NULL);
960 #endif
961         } else if (ssl_cainfo != NULL || http_proxy_ssl_ca_info != NULL) {
962                 if (ssl_cainfo != NULL)
963                         curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
964 #if LIBCURL_VERSION_NUM >= 0x073400
965                 if (http_proxy_ssl_ca_info != NULL)
966                         curl_easy_setopt(result, CURLOPT_PROXY_CAINFO, http_proxy_ssl_ca_info);
967 #endif
968         }
969
970         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
971                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
972                                  curl_low_speed_limit);
973                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
974                                  curl_low_speed_time);
975         }
976
977         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
978 #if LIBCURL_VERSION_NUM >= 0x071301
979         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
980 #elif LIBCURL_VERSION_NUM >= 0x071101
981         curl_easy_setopt(result, CURLOPT_POST301, 1);
982 #endif
983 #ifdef CURLPROTO_HTTP
984         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS,
985                          get_curl_allowed_protocols(0));
986         curl_easy_setopt(result, CURLOPT_PROTOCOLS,
987                          get_curl_allowed_protocols(-1));
988 #else
989         warning(_("Protocol restrictions not supported with cURL < 7.19.4"));
990 #endif
991         if (getenv("GIT_CURL_VERBOSE"))
992                 http_trace_curl_no_data();
993         setup_curl_trace(result);
994         if (getenv("GIT_TRACE_CURL_NO_DATA"))
995                 trace_curl_data = 0;
996         if (!git_env_bool("GIT_TRACE_REDACT", 1))
997                 trace_curl_redact = 0;
998
999         curl_easy_setopt(result, CURLOPT_USERAGENT,
1000                 user_agent ? user_agent : git_user_agent());
1001
1002         if (curl_ftp_no_epsv)
1003                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
1004
1005 #ifdef CURLOPT_USE_SSL
1006         if (curl_ssl_try)
1007                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
1008 #endif
1009
1010         /*
1011          * CURL also examines these variables as a fallback; but we need to query
1012          * them here in order to decide whether to prompt for missing password (cf.
1013          * init_curl_proxy_auth()).
1014          *
1015          * Unlike many other common environment variables, these are historically
1016          * lowercase only. It appears that CURL did not know this and implemented
1017          * only uppercase variants, which was later corrected to take both - with
1018          * the exception of http_proxy, which is lowercase only also in CURL. As
1019          * the lowercase versions are the historical quasi-standard, they take
1020          * precedence here, as in CURL.
1021          */
1022         if (!curl_http_proxy) {
1023                 if (http_auth.protocol && !strcmp(http_auth.protocol, "https")) {
1024                         var_override(&curl_http_proxy, getenv("HTTPS_PROXY"));
1025                         var_override(&curl_http_proxy, getenv("https_proxy"));
1026                 } else {
1027                         var_override(&curl_http_proxy, getenv("http_proxy"));
1028                 }
1029                 if (!curl_http_proxy) {
1030                         var_override(&curl_http_proxy, getenv("ALL_PROXY"));
1031                         var_override(&curl_http_proxy, getenv("all_proxy"));
1032                 }
1033         }
1034
1035         if (curl_http_proxy && curl_http_proxy[0] == '\0') {
1036                 /*
1037                  * Handle case with the empty http.proxy value here to keep
1038                  * common code clean.
1039                  * NB: empty option disables proxying at all.
1040                  */
1041                 curl_easy_setopt(result, CURLOPT_PROXY, "");
1042         } else if (curl_http_proxy) {
1043 #if LIBCURL_VERSION_NUM >= 0x071800
1044                 if (starts_with(curl_http_proxy, "socks5h"))
1045                         curl_easy_setopt(result,
1046                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
1047                 else if (starts_with(curl_http_proxy, "socks5"))
1048                         curl_easy_setopt(result,
1049                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
1050                 else if (starts_with(curl_http_proxy, "socks4a"))
1051                         curl_easy_setopt(result,
1052                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
1053                 else if (starts_with(curl_http_proxy, "socks"))
1054                         curl_easy_setopt(result,
1055                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
1056 #endif
1057 #if LIBCURL_VERSION_NUM >= 0x073400
1058                 else if (starts_with(curl_http_proxy, "https")) {
1059                         curl_easy_setopt(result, CURLOPT_PROXYTYPE, CURLPROXY_HTTPS);
1060
1061                         if (http_proxy_ssl_cert)
1062                                 curl_easy_setopt(result, CURLOPT_PROXY_SSLCERT, http_proxy_ssl_cert);
1063
1064                         if (http_proxy_ssl_key)
1065                                 curl_easy_setopt(result, CURLOPT_PROXY_SSLKEY, http_proxy_ssl_key);
1066
1067                         if (has_proxy_cert_password())
1068                                 curl_easy_setopt(result, CURLOPT_PROXY_KEYPASSWD, proxy_cert_auth.password);
1069                 }
1070 #endif
1071                 if (strstr(curl_http_proxy, "://"))
1072                         credential_from_url(&proxy_auth, curl_http_proxy);
1073                 else {
1074                         struct strbuf url = STRBUF_INIT;
1075                         strbuf_addf(&url, "http://%s", curl_http_proxy);
1076                         credential_from_url(&proxy_auth, url.buf);
1077                         strbuf_release(&url);
1078                 }
1079
1080                 if (!proxy_auth.host)
1081                         die("Invalid proxy URL '%s'", curl_http_proxy);
1082
1083                 curl_easy_setopt(result, CURLOPT_PROXY, proxy_auth.host);
1084 #if LIBCURL_VERSION_NUM >= 0x071304
1085                 var_override(&curl_no_proxy, getenv("NO_PROXY"));
1086                 var_override(&curl_no_proxy, getenv("no_proxy"));
1087                 curl_easy_setopt(result, CURLOPT_NOPROXY, curl_no_proxy);
1088 #endif
1089         }
1090         init_curl_proxy_auth(result);
1091
1092         set_curl_keepalive(result);
1093
1094         return result;
1095 }
1096
1097 static void set_from_env(const char **var, const char *envname)
1098 {
1099         const char *val = getenv(envname);
1100         if (val)
1101                 *var = val;
1102 }
1103
1104 void http_init(struct remote *remote, const char *url, int proactive_auth)
1105 {
1106         char *low_speed_limit;
1107         char *low_speed_time;
1108         char *normalized_url;
1109         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
1110
1111         config.section = "http";
1112         config.key = NULL;
1113         config.collect_fn = http_options;
1114         config.cascade_fn = git_default_config;
1115         config.cb = NULL;
1116
1117         http_is_verbose = 0;
1118         normalized_url = url_normalize(url, &config.url);
1119
1120         git_config(urlmatch_config_entry, &config);
1121         free(normalized_url);
1122         string_list_clear(&config.vars, 1);
1123
1124 #if LIBCURL_VERSION_NUM >= 0x073800
1125         if (http_ssl_backend) {
1126                 const curl_ssl_backend **backends;
1127                 struct strbuf buf = STRBUF_INIT;
1128                 int i;
1129
1130                 switch (curl_global_sslset(-1, http_ssl_backend, &backends)) {
1131                 case CURLSSLSET_UNKNOWN_BACKEND:
1132                         strbuf_addf(&buf, _("Unsupported SSL backend '%s'. "
1133                                             "Supported SSL backends:"),
1134                                             http_ssl_backend);
1135                         for (i = 0; backends[i]; i++)
1136                                 strbuf_addf(&buf, "\n\t%s", backends[i]->name);
1137                         die("%s", buf.buf);
1138                 case CURLSSLSET_NO_BACKENDS:
1139                         die(_("Could not set SSL backend to '%s': "
1140                               "cURL was built without SSL backends"),
1141                             http_ssl_backend);
1142                 case CURLSSLSET_TOO_LATE:
1143                         die(_("Could not set SSL backend to '%s': already set"),
1144                             http_ssl_backend);
1145                 case CURLSSLSET_OK:
1146                         break; /* Okay! */
1147                 }
1148         }
1149 #endif
1150
1151         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
1152                 die("curl_global_init failed");
1153
1154         http_proactive_auth = proactive_auth;
1155
1156         if (remote && remote->http_proxy)
1157                 curl_http_proxy = xstrdup(remote->http_proxy);
1158
1159         if (remote)
1160                 var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
1161
1162         pragma_header = curl_slist_append(http_copy_default_headers(),
1163                 "Pragma: no-cache");
1164         no_pragma_header = curl_slist_append(http_copy_default_headers(),
1165                 "Pragma:");
1166
1167 #ifdef USE_CURL_MULTI
1168         {
1169                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
1170                 if (http_max_requests != NULL)
1171                         max_requests = atoi(http_max_requests);
1172         }
1173
1174         curlm = curl_multi_init();
1175         if (!curlm)
1176                 die("curl_multi_init failed");
1177 #endif
1178
1179         if (getenv("GIT_SSL_NO_VERIFY"))
1180                 curl_ssl_verify = 0;
1181
1182         set_from_env(&ssl_cert, "GIT_SSL_CERT");
1183 #if LIBCURL_VERSION_NUM >= 0x070903
1184         set_from_env(&ssl_key, "GIT_SSL_KEY");
1185 #endif
1186 #if LIBCURL_VERSION_NUM >= 0x070908
1187         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
1188 #endif
1189         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
1190
1191         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
1192
1193         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
1194         if (low_speed_limit != NULL)
1195                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
1196         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
1197         if (low_speed_time != NULL)
1198                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
1199
1200         if (curl_ssl_verify == -1)
1201                 curl_ssl_verify = 1;
1202
1203         curl_session_count = 0;
1204 #ifdef USE_CURL_MULTI
1205         if (max_requests < 1)
1206                 max_requests = DEFAULT_MAX_REQUESTS;
1207 #endif
1208
1209         set_from_env(&http_proxy_ssl_cert, "GIT_PROXY_SSL_CERT");
1210         set_from_env(&http_proxy_ssl_key, "GIT_PROXY_SSL_KEY");
1211         set_from_env(&http_proxy_ssl_ca_info, "GIT_PROXY_SSL_CAINFO");
1212
1213         if (getenv("GIT_PROXY_SSL_CERT_PASSWORD_PROTECTED"))
1214                 proxy_ssl_cert_password_required = 1;
1215
1216         if (getenv("GIT_CURL_FTP_NO_EPSV"))
1217                 curl_ftp_no_epsv = 1;
1218
1219         if (url) {
1220                 credential_from_url(&http_auth, url);
1221                 if (!ssl_cert_password_required &&
1222                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
1223                     starts_with(url, "https://"))
1224                         ssl_cert_password_required = 1;
1225         }
1226
1227 #ifndef NO_CURL_EASY_DUPHANDLE
1228         curl_default = get_curl_handle();
1229 #endif
1230 }
1231
1232 void http_cleanup(void)
1233 {
1234         struct active_request_slot *slot = active_queue_head;
1235
1236         while (slot != NULL) {
1237                 struct active_request_slot *next = slot->next;
1238                 if (slot->curl != NULL) {
1239                         xmulti_remove_handle(slot);
1240                         curl_easy_cleanup(slot->curl);
1241                 }
1242                 free(slot);
1243                 slot = next;
1244         }
1245         active_queue_head = NULL;
1246
1247 #ifndef NO_CURL_EASY_DUPHANDLE
1248         curl_easy_cleanup(curl_default);
1249 #endif
1250
1251 #ifdef USE_CURL_MULTI
1252         curl_multi_cleanup(curlm);
1253 #endif
1254         curl_global_cleanup();
1255
1256         string_list_clear(&extra_http_headers, 0);
1257
1258         curl_slist_free_all(pragma_header);
1259         pragma_header = NULL;
1260
1261         curl_slist_free_all(no_pragma_header);
1262         no_pragma_header = NULL;
1263
1264         if (curl_http_proxy) {
1265                 free((void *)curl_http_proxy);
1266                 curl_http_proxy = NULL;
1267         }
1268
1269         if (proxy_auth.password) {
1270                 memset(proxy_auth.password, 0, strlen(proxy_auth.password));
1271                 FREE_AND_NULL(proxy_auth.password);
1272         }
1273
1274         free((void *)curl_proxyuserpwd);
1275         curl_proxyuserpwd = NULL;
1276
1277         free((void *)http_proxy_authmethod);
1278         http_proxy_authmethod = NULL;
1279
1280         if (cert_auth.password != NULL) {
1281                 memset(cert_auth.password, 0, strlen(cert_auth.password));
1282                 FREE_AND_NULL(cert_auth.password);
1283         }
1284         ssl_cert_password_required = 0;
1285
1286         if (proxy_cert_auth.password != NULL) {
1287                 memset(proxy_cert_auth.password, 0, strlen(proxy_cert_auth.password));
1288                 FREE_AND_NULL(proxy_cert_auth.password);
1289         }
1290         proxy_ssl_cert_password_required = 0;
1291
1292         FREE_AND_NULL(cached_accept_language);
1293 }
1294
1295 struct active_request_slot *get_active_slot(void)
1296 {
1297         struct active_request_slot *slot = active_queue_head;
1298         struct active_request_slot *newslot;
1299
1300 #ifdef USE_CURL_MULTI
1301         int num_transfers;
1302
1303         /* Wait for a slot to open up if the queue is full */
1304         while (active_requests >= max_requests) {
1305                 curl_multi_perform(curlm, &num_transfers);
1306                 if (num_transfers < active_requests)
1307                         process_curl_messages();
1308         }
1309 #endif
1310
1311         while (slot != NULL && slot->in_use)
1312                 slot = slot->next;
1313
1314         if (slot == NULL) {
1315                 newslot = xmalloc(sizeof(*newslot));
1316                 newslot->curl = NULL;
1317                 newslot->in_use = 0;
1318                 newslot->next = NULL;
1319
1320                 slot = active_queue_head;
1321                 if (slot == NULL) {
1322                         active_queue_head = newslot;
1323                 } else {
1324                         while (slot->next != NULL)
1325                                 slot = slot->next;
1326                         slot->next = newslot;
1327                 }
1328                 slot = newslot;
1329         }
1330
1331         if (slot->curl == NULL) {
1332 #ifdef NO_CURL_EASY_DUPHANDLE
1333                 slot->curl = get_curl_handle();
1334 #else
1335                 slot->curl = curl_easy_duphandle(curl_default);
1336 #endif
1337                 curl_session_count++;
1338         }
1339
1340         active_requests++;
1341         slot->in_use = 1;
1342         slot->results = NULL;
1343         slot->finished = NULL;
1344         slot->callback_data = NULL;
1345         slot->callback_func = NULL;
1346         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
1347         if (curl_save_cookies)
1348                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
1349         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
1350         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
1351         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
1352         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
1353         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
1354         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
1355         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
1356         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1357         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
1358         curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
1359
1360         /*
1361          * Default following to off unless "ALWAYS" is configured; this gives
1362          * callers a sane starting point, and they can tweak for individual
1363          * HTTP_FOLLOW_* cases themselves.
1364          */
1365         if (http_follow_config == HTTP_FOLLOW_ALWAYS)
1366                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1367         else
1368                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 0);
1369
1370 #if LIBCURL_VERSION_NUM >= 0x070a08
1371         curl_easy_setopt(slot->curl, CURLOPT_IPRESOLVE, git_curl_ipresolve);
1372 #endif
1373 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1374         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
1375 #endif
1376         if (http_auth.password || curl_empty_auth_enabled())
1377                 init_curl_http_auth(slot->curl);
1378
1379         return slot;
1380 }
1381
1382 int start_active_slot(struct active_request_slot *slot)
1383 {
1384 #ifdef USE_CURL_MULTI
1385         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
1386         int num_transfers;
1387
1388         if (curlm_result != CURLM_OK &&
1389             curlm_result != CURLM_CALL_MULTI_PERFORM) {
1390                 warning("curl_multi_add_handle failed: %s",
1391                         curl_multi_strerror(curlm_result));
1392                 active_requests--;
1393                 slot->in_use = 0;
1394                 return 0;
1395         }
1396
1397         /*
1398          * We know there must be something to do, since we just added
1399          * something.
1400          */
1401         curl_multi_perform(curlm, &num_transfers);
1402 #endif
1403         return 1;
1404 }
1405
1406 #ifdef USE_CURL_MULTI
1407 struct fill_chain {
1408         void *data;
1409         int (*fill)(void *);
1410         struct fill_chain *next;
1411 };
1412
1413 static struct fill_chain *fill_cfg;
1414
1415 void add_fill_function(void *data, int (*fill)(void *))
1416 {
1417         struct fill_chain *new_fill = xmalloc(sizeof(*new_fill));
1418         struct fill_chain **linkp = &fill_cfg;
1419         new_fill->data = data;
1420         new_fill->fill = fill;
1421         new_fill->next = NULL;
1422         while (*linkp)
1423                 linkp = &(*linkp)->next;
1424         *linkp = new_fill;
1425 }
1426
1427 void fill_active_slots(void)
1428 {
1429         struct active_request_slot *slot = active_queue_head;
1430
1431         while (active_requests < max_requests) {
1432                 struct fill_chain *fill;
1433                 for (fill = fill_cfg; fill; fill = fill->next)
1434                         if (fill->fill(fill->data))
1435                                 break;
1436
1437                 if (!fill)
1438                         break;
1439         }
1440
1441         while (slot != NULL) {
1442                 if (!slot->in_use && slot->curl != NULL
1443                         && curl_session_count > min_curl_sessions) {
1444                         curl_easy_cleanup(slot->curl);
1445                         slot->curl = NULL;
1446                         curl_session_count--;
1447                 }
1448                 slot = slot->next;
1449         }
1450 }
1451
1452 void step_active_slots(void)
1453 {
1454         int num_transfers;
1455         CURLMcode curlm_result;
1456
1457         do {
1458                 curlm_result = curl_multi_perform(curlm, &num_transfers);
1459         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
1460         if (num_transfers < active_requests) {
1461                 process_curl_messages();
1462                 fill_active_slots();
1463         }
1464 }
1465 #endif
1466
1467 void run_active_slot(struct active_request_slot *slot)
1468 {
1469 #ifdef USE_CURL_MULTI
1470         fd_set readfds;
1471         fd_set writefds;
1472         fd_set excfds;
1473         int max_fd;
1474         struct timeval select_timeout;
1475         int finished = 0;
1476
1477         slot->finished = &finished;
1478         while (!finished) {
1479                 step_active_slots();
1480
1481                 if (slot->in_use) {
1482 #if LIBCURL_VERSION_NUM >= 0x070f04
1483                         long curl_timeout;
1484                         curl_multi_timeout(curlm, &curl_timeout);
1485                         if (curl_timeout == 0) {
1486                                 continue;
1487                         } else if (curl_timeout == -1) {
1488                                 select_timeout.tv_sec  = 0;
1489                                 select_timeout.tv_usec = 50000;
1490                         } else {
1491                                 select_timeout.tv_sec  =  curl_timeout / 1000;
1492                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
1493                         }
1494 #else
1495                         select_timeout.tv_sec  = 0;
1496                         select_timeout.tv_usec = 50000;
1497 #endif
1498
1499                         max_fd = -1;
1500                         FD_ZERO(&readfds);
1501                         FD_ZERO(&writefds);
1502                         FD_ZERO(&excfds);
1503                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
1504
1505                         /*
1506                          * It can happen that curl_multi_timeout returns a pathologically
1507                          * long timeout when curl_multi_fdset returns no file descriptors
1508                          * to read.  See commit message for more details.
1509                          */
1510                         if (max_fd < 0 &&
1511                             (select_timeout.tv_sec > 0 ||
1512                              select_timeout.tv_usec > 50000)) {
1513                                 select_timeout.tv_sec  = 0;
1514                                 select_timeout.tv_usec = 50000;
1515                         }
1516
1517                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
1518                 }
1519         }
1520 #else
1521         while (slot->in_use) {
1522                 slot->curl_result = curl_easy_perform(slot->curl);
1523                 finish_active_slot(slot);
1524         }
1525 #endif
1526 }
1527
1528 static void release_active_slot(struct active_request_slot *slot)
1529 {
1530         closedown_active_slot(slot);
1531         if (slot->curl) {
1532                 xmulti_remove_handle(slot);
1533                 if (curl_session_count > min_curl_sessions) {
1534                         curl_easy_cleanup(slot->curl);
1535                         slot->curl = NULL;
1536                         curl_session_count--;
1537                 }
1538         }
1539 #ifdef USE_CURL_MULTI
1540         fill_active_slots();
1541 #endif
1542 }
1543
1544 void finish_all_active_slots(void)
1545 {
1546         struct active_request_slot *slot = active_queue_head;
1547
1548         while (slot != NULL)
1549                 if (slot->in_use) {
1550                         run_active_slot(slot);
1551                         slot = active_queue_head;
1552                 } else {
1553                         slot = slot->next;
1554                 }
1555 }
1556
1557 /* Helpers for modifying and creating URLs */
1558 static inline int needs_quote(int ch)
1559 {
1560         if (((ch >= 'A') && (ch <= 'Z'))
1561                         || ((ch >= 'a') && (ch <= 'z'))
1562                         || ((ch >= '0') && (ch <= '9'))
1563                         || (ch == '/')
1564                         || (ch == '-')
1565                         || (ch == '.'))
1566                 return 0;
1567         return 1;
1568 }
1569
1570 static char *quote_ref_url(const char *base, const char *ref)
1571 {
1572         struct strbuf buf = STRBUF_INIT;
1573         const char *cp;
1574         int ch;
1575
1576         end_url_with_slash(&buf, base);
1577
1578         for (cp = ref; (ch = *cp) != 0; cp++)
1579                 if (needs_quote(ch))
1580                         strbuf_addf(&buf, "%%%02x", ch);
1581                 else
1582                         strbuf_addch(&buf, *cp);
1583
1584         return strbuf_detach(&buf, NULL);
1585 }
1586
1587 void append_remote_object_url(struct strbuf *buf, const char *url,
1588                               const char *hex,
1589                               int only_two_digit_prefix)
1590 {
1591         end_url_with_slash(buf, url);
1592
1593         strbuf_addf(buf, "objects/%.*s/", 2, hex);
1594         if (!only_two_digit_prefix)
1595                 strbuf_addstr(buf, hex + 2);
1596 }
1597
1598 char *get_remote_object_url(const char *url, const char *hex,
1599                             int only_two_digit_prefix)
1600 {
1601         struct strbuf buf = STRBUF_INIT;
1602         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
1603         return strbuf_detach(&buf, NULL);
1604 }
1605
1606 void normalize_curl_result(CURLcode *result, long http_code,
1607                            char *errorstr, size_t errorlen)
1608 {
1609         /*
1610          * If we see a failing http code with CURLE_OK, we have turned off
1611          * FAILONERROR (to keep the server's custom error response), and should
1612          * translate the code into failure here.
1613          *
1614          * Likewise, if we see a redirect (30x code), that means we turned off
1615          * redirect-following, and we should treat the result as an error.
1616          */
1617         if (*result == CURLE_OK && http_code >= 300) {
1618                 *result = CURLE_HTTP_RETURNED_ERROR;
1619                 /*
1620                  * Normally curl will already have put the "reason phrase"
1621                  * from the server into curl_errorstr; unfortunately without
1622                  * FAILONERROR it is lost, so we can give only the numeric
1623                  * status code.
1624                  */
1625                 xsnprintf(errorstr, errorlen,
1626                           "The requested URL returned error: %ld",
1627                           http_code);
1628         }
1629 }
1630
1631 static int handle_curl_result(struct slot_results *results)
1632 {
1633         normalize_curl_result(&results->curl_result, results->http_code,
1634                               curl_errorstr, sizeof(curl_errorstr));
1635
1636         if (results->curl_result == CURLE_OK) {
1637                 credential_approve(&http_auth);
1638                 if (proxy_auth.password)
1639                         credential_approve(&proxy_auth);
1640                 return HTTP_OK;
1641         } else if (missing_target(results))
1642                 return HTTP_MISSING_TARGET;
1643         else if (results->http_code == 401) {
1644                 if (http_auth.username && http_auth.password) {
1645                         credential_reject(&http_auth);
1646                         return HTTP_NOAUTH;
1647                 } else {
1648 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1649                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
1650                         if (results->auth_avail) {
1651                                 http_auth_methods &= results->auth_avail;
1652                                 http_auth_methods_restricted = 1;
1653                         }
1654 #endif
1655                         return HTTP_REAUTH;
1656                 }
1657         } else {
1658                 if (results->http_connectcode == 407)
1659                         credential_reject(&proxy_auth);
1660 #if LIBCURL_VERSION_NUM >= 0x070c00
1661                 if (!curl_errorstr[0])
1662                         strlcpy(curl_errorstr,
1663                                 curl_easy_strerror(results->curl_result),
1664                                 sizeof(curl_errorstr));
1665 #endif
1666                 return HTTP_ERROR;
1667         }
1668 }
1669
1670 int run_one_slot(struct active_request_slot *slot,
1671                  struct slot_results *results)
1672 {
1673         slot->results = results;
1674         if (!start_active_slot(slot)) {
1675                 xsnprintf(curl_errorstr, sizeof(curl_errorstr),
1676                           "failed to start HTTP request");
1677                 return HTTP_START_FAILED;
1678         }
1679
1680         run_active_slot(slot);
1681         return handle_curl_result(results);
1682 }
1683
1684 struct curl_slist *http_copy_default_headers(void)
1685 {
1686         struct curl_slist *headers = NULL;
1687         const struct string_list_item *item;
1688
1689         for_each_string_list_item(item, &extra_http_headers)
1690                 headers = curl_slist_append(headers, item->string);
1691
1692         return headers;
1693 }
1694
1695 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
1696 {
1697         char *ptr;
1698         CURLcode ret;
1699
1700         strbuf_reset(buf);
1701         ret = curl_easy_getinfo(curl, info, &ptr);
1702         if (!ret && ptr)
1703                 strbuf_addstr(buf, ptr);
1704         return ret;
1705 }
1706
1707 /*
1708  * Check for and extract a content-type parameter. "raw"
1709  * should be positioned at the start of the potential
1710  * parameter, with any whitespace already removed.
1711  *
1712  * "name" is the name of the parameter. The value is appended
1713  * to "out".
1714  */
1715 static int extract_param(const char *raw, const char *name,
1716                          struct strbuf *out)
1717 {
1718         size_t len = strlen(name);
1719
1720         if (strncasecmp(raw, name, len))
1721                 return -1;
1722         raw += len;
1723
1724         if (*raw != '=')
1725                 return -1;
1726         raw++;
1727
1728         while (*raw && !isspace(*raw) && *raw != ';')
1729                 strbuf_addch(out, *raw++);
1730         return 0;
1731 }
1732
1733 /*
1734  * Extract a normalized version of the content type, with any
1735  * spaces suppressed, all letters lowercased, and no trailing ";"
1736  * or parameters.
1737  *
1738  * Note that we will silently remove even invalid whitespace. For
1739  * example, "text / plain" is specifically forbidden by RFC 2616,
1740  * but "text/plain" is the only reasonable output, and this keeps
1741  * our code simple.
1742  *
1743  * If the "charset" argument is not NULL, store the value of any
1744  * charset parameter there.
1745  *
1746  * Example:
1747  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1748  *   "text / plain" -> "text/plain"
1749  */
1750 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1751                                  struct strbuf *charset)
1752 {
1753         const char *p;
1754
1755         strbuf_reset(type);
1756         strbuf_grow(type, raw->len);
1757         for (p = raw->buf; *p; p++) {
1758                 if (isspace(*p))
1759                         continue;
1760                 if (*p == ';') {
1761                         p++;
1762                         break;
1763                 }
1764                 strbuf_addch(type, tolower(*p));
1765         }
1766
1767         if (!charset)
1768                 return;
1769
1770         strbuf_reset(charset);
1771         while (*p) {
1772                 while (isspace(*p) || *p == ';')
1773                         p++;
1774                 if (!extract_param(p, "charset", charset))
1775                         return;
1776                 while (*p && !isspace(*p))
1777                         p++;
1778         }
1779
1780         if (!charset->len && starts_with(type->buf, "text/"))
1781                 strbuf_addstr(charset, "ISO-8859-1");
1782 }
1783
1784 static void write_accept_language(struct strbuf *buf)
1785 {
1786         /*
1787          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1788          * that, q-value will be smaller than 0.001, the minimum q-value the
1789          * HTTP specification allows. See
1790          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1791          */
1792         const int MAX_DECIMAL_PLACES = 3;
1793         const int MAX_LANGUAGE_TAGS = 1000;
1794         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1795         char **language_tags = NULL;
1796         int num_langs = 0;
1797         const char *s = get_preferred_languages();
1798         int i;
1799         struct strbuf tag = STRBUF_INIT;
1800
1801         /* Don't add Accept-Language header if no language is preferred. */
1802         if (!s)
1803                 return;
1804
1805         /*
1806          * Split the colon-separated string of preferred languages into
1807          * language_tags array.
1808          */
1809         do {
1810                 /* collect language tag */
1811                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1812                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1813
1814                 /* skip .codeset, @modifier and any other unnecessary parts */
1815                 while (*s && *s != ':')
1816                         s++;
1817
1818                 if (tag.len) {
1819                         num_langs++;
1820                         REALLOC_ARRAY(language_tags, num_langs);
1821                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1822                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1823                                 break;
1824                 }
1825         } while (*s++);
1826
1827         /* write Accept-Language header into buf */
1828         if (num_langs) {
1829                 int last_buf_len = 0;
1830                 int max_q;
1831                 int decimal_places;
1832                 char q_format[32];
1833
1834                 /* add '*' */
1835                 REALLOC_ARRAY(language_tags, num_langs + 1);
1836                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1837
1838                 /* compute decimal_places */
1839                 for (max_q = 1, decimal_places = 0;
1840                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1841                      decimal_places++, max_q *= 10)
1842                         ;
1843
1844                 xsnprintf(q_format, sizeof(q_format), ";q=0.%%0%dd", decimal_places);
1845
1846                 strbuf_addstr(buf, "Accept-Language: ");
1847
1848                 for (i = 0; i < num_langs; i++) {
1849                         if (i > 0)
1850                                 strbuf_addstr(buf, ", ");
1851
1852                         strbuf_addstr(buf, language_tags[i]);
1853
1854                         if (i > 0)
1855                                 strbuf_addf(buf, q_format, max_q - i);
1856
1857                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1858                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1859                                 break;
1860                         }
1861
1862                         last_buf_len = buf->len;
1863                 }
1864         }
1865
1866         /* free language tags -- last one is a static '*' */
1867         for (i = 0; i < num_langs - 1; i++)
1868                 free(language_tags[i]);
1869         free(language_tags);
1870 }
1871
1872 /*
1873  * Get an Accept-Language header which indicates user's preferred languages.
1874  *
1875  * Examples:
1876  *   LANGUAGE= -> ""
1877  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1878  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1879  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1880  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1881  *   LANGUAGE= LANG=C -> ""
1882  */
1883 static const char *get_accept_language(void)
1884 {
1885         if (!cached_accept_language) {
1886                 struct strbuf buf = STRBUF_INIT;
1887                 write_accept_language(&buf);
1888                 if (buf.len > 0)
1889                         cached_accept_language = strbuf_detach(&buf, NULL);
1890         }
1891
1892         return cached_accept_language;
1893 }
1894
1895 static void http_opt_request_remainder(CURL *curl, off_t pos)
1896 {
1897         char buf[128];
1898         xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1899         curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1900 }
1901
1902 /* http_request() targets */
1903 #define HTTP_REQUEST_STRBUF     0
1904 #define HTTP_REQUEST_FILE       1
1905
1906 static int http_request(const char *url,
1907                         void *result, int target,
1908                         const struct http_get_options *options)
1909 {
1910         struct active_request_slot *slot;
1911         struct slot_results results;
1912         struct curl_slist *headers = http_copy_default_headers();
1913         struct strbuf buf = STRBUF_INIT;
1914         const char *accept_language;
1915         int ret;
1916
1917         slot = get_active_slot();
1918         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1919
1920         if (result == NULL) {
1921                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1922         } else {
1923                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1924                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1925
1926                 if (target == HTTP_REQUEST_FILE) {
1927                         off_t posn = ftello(result);
1928                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1929                                          fwrite);
1930                         if (posn > 0)
1931                                 http_opt_request_remainder(slot->curl, posn);
1932                 } else
1933                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1934                                          fwrite_buffer);
1935         }
1936
1937         accept_language = get_accept_language();
1938
1939         if (accept_language)
1940                 headers = curl_slist_append(headers, accept_language);
1941
1942         strbuf_addstr(&buf, "Pragma:");
1943         if (options && options->no_cache)
1944                 strbuf_addstr(&buf, " no-cache");
1945         if (options && options->initial_request &&
1946             http_follow_config == HTTP_FOLLOW_INITIAL)
1947                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1948
1949         headers = curl_slist_append(headers, buf.buf);
1950
1951         /* Add additional headers here */
1952         if (options && options->extra_headers) {
1953                 const struct string_list_item *item;
1954                 for_each_string_list_item(item, options->extra_headers) {
1955                         headers = curl_slist_append(headers, item->string);
1956                 }
1957         }
1958
1959         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1960         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1961         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
1962         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1963
1964         ret = run_one_slot(slot, &results);
1965
1966         if (options && options->content_type) {
1967                 struct strbuf raw = STRBUF_INIT;
1968                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1969                 extract_content_type(&raw, options->content_type,
1970                                      options->charset);
1971                 strbuf_release(&raw);
1972         }
1973
1974         if (options && options->effective_url)
1975                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1976                                 options->effective_url);
1977
1978         curl_slist_free_all(headers);
1979         strbuf_release(&buf);
1980
1981         return ret;
1982 }
1983
1984 /*
1985  * Update the "base" url to a more appropriate value, as deduced by
1986  * redirects seen when requesting a URL starting with "url".
1987  *
1988  * The "asked" parameter is a URL that we asked curl to access, and must begin
1989  * with "base".
1990  *
1991  * The "got" parameter is the URL that curl reported to us as where we ended
1992  * up.
1993  *
1994  * Returns 1 if we updated the base url, 0 otherwise.
1995  *
1996  * Our basic strategy is to compare "base" and "asked" to find the bits
1997  * specific to our request. We then strip those bits off of "got" to yield the
1998  * new base. So for example, if our base is "http://example.com/foo.git",
1999  * and we ask for "http://example.com/foo.git/info/refs", we might end up
2000  * with "https://other.example.com/foo.git/info/refs". We would want the
2001  * new URL to become "https://other.example.com/foo.git".
2002  *
2003  * Note that this assumes a sane redirect scheme. It's entirely possible
2004  * in the example above to end up at a URL that does not even end in
2005  * "info/refs".  In such a case we die. There's not much we can do, such a
2006  * scheme is unlikely to represent a real git repository, and failing to
2007  * rewrite the base opens options for malicious redirects to do funny things.
2008  */
2009 static int update_url_from_redirect(struct strbuf *base,
2010                                     const char *asked,
2011                                     const struct strbuf *got)
2012 {
2013         const char *tail;
2014         size_t new_len;
2015
2016         if (!strcmp(asked, got->buf))
2017                 return 0;
2018
2019         if (!skip_prefix(asked, base->buf, &tail))
2020                 BUG("update_url_from_redirect: %s is not a superset of %s",
2021                     asked, base->buf);
2022
2023         new_len = got->len;
2024         if (!strip_suffix_mem(got->buf, &new_len, tail))
2025                 die(_("unable to update url base from redirection:\n"
2026                       "  asked for: %s\n"
2027                       "   redirect: %s"),
2028                     asked, got->buf);
2029
2030         strbuf_reset(base);
2031         strbuf_add(base, got->buf, new_len);
2032
2033         return 1;
2034 }
2035
2036 static int http_request_reauth(const char *url,
2037                                void *result, int target,
2038                                struct http_get_options *options)
2039 {
2040         int ret = http_request(url, result, target, options);
2041
2042         if (ret != HTTP_OK && ret != HTTP_REAUTH)
2043                 return ret;
2044
2045         if (options && options->effective_url && options->base_url) {
2046                 if (update_url_from_redirect(options->base_url,
2047                                              url, options->effective_url)) {
2048                         credential_from_url(&http_auth, options->base_url->buf);
2049                         url = options->effective_url->buf;
2050                 }
2051         }
2052
2053         if (ret != HTTP_REAUTH)
2054                 return ret;
2055
2056         /*
2057          * The previous request may have put cruft into our output stream; we
2058          * should clear it out before making our next request.
2059          */
2060         switch (target) {
2061         case HTTP_REQUEST_STRBUF:
2062                 strbuf_reset(result);
2063                 break;
2064         case HTTP_REQUEST_FILE:
2065                 if (fflush(result)) {
2066                         error_errno("unable to flush a file");
2067                         return HTTP_START_FAILED;
2068                 }
2069                 rewind(result);
2070                 if (ftruncate(fileno(result), 0) < 0) {
2071                         error_errno("unable to truncate a file");
2072                         return HTTP_START_FAILED;
2073                 }
2074                 break;
2075         default:
2076                 BUG("Unknown http_request target");
2077         }
2078
2079         credential_fill(&http_auth);
2080
2081         return http_request(url, result, target, options);
2082 }
2083
2084 int http_get_strbuf(const char *url,
2085                     struct strbuf *result,
2086                     struct http_get_options *options)
2087 {
2088         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
2089 }
2090
2091 /*
2092  * Downloads a URL and stores the result in the given file.
2093  *
2094  * If a previous interrupted download is detected (i.e. a previous temporary
2095  * file is still around) the download is resumed.
2096  */
2097 static int http_get_file(const char *url, const char *filename,
2098                          struct http_get_options *options)
2099 {
2100         int ret;
2101         struct strbuf tmpfile = STRBUF_INIT;
2102         FILE *result;
2103
2104         strbuf_addf(&tmpfile, "%s.temp", filename);
2105         result = fopen(tmpfile.buf, "a");
2106         if (!result) {
2107                 error("Unable to open local file %s", tmpfile.buf);
2108                 ret = HTTP_ERROR;
2109                 goto cleanup;
2110         }
2111
2112         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
2113         fclose(result);
2114
2115         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
2116                 ret = HTTP_ERROR;
2117 cleanup:
2118         strbuf_release(&tmpfile);
2119         return ret;
2120 }
2121
2122 int http_fetch_ref(const char *base, struct ref *ref)
2123 {
2124         struct http_get_options options = {0};
2125         char *url;
2126         struct strbuf buffer = STRBUF_INIT;
2127         int ret = -1;
2128
2129         options.no_cache = 1;
2130
2131         url = quote_ref_url(base, ref->name);
2132         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
2133                 strbuf_rtrim(&buffer);
2134                 if (buffer.len == the_hash_algo->hexsz)
2135                         ret = get_oid_hex(buffer.buf, &ref->old_oid);
2136                 else if (starts_with(buffer.buf, "ref: ")) {
2137                         ref->symref = xstrdup(buffer.buf + 5);
2138                         ret = 0;
2139                 }
2140         }
2141
2142         strbuf_release(&buffer);
2143         free(url);
2144         return ret;
2145 }
2146
2147 /* Helpers for fetching packs */
2148 static char *fetch_pack_index(unsigned char *hash, const char *base_url)
2149 {
2150         char *url, *tmp;
2151         struct strbuf buf = STRBUF_INIT;
2152
2153         if (http_is_verbose)
2154                 fprintf(stderr, "Getting index for pack %s\n", hash_to_hex(hash));
2155
2156         end_url_with_slash(&buf, base_url);
2157         strbuf_addf(&buf, "objects/pack/pack-%s.idx", hash_to_hex(hash));
2158         url = strbuf_detach(&buf, NULL);
2159
2160         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(hash));
2161         tmp = strbuf_detach(&buf, NULL);
2162
2163         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
2164                 error("Unable to get pack index %s", url);
2165                 FREE_AND_NULL(tmp);
2166         }
2167
2168         free(url);
2169         return tmp;
2170 }
2171
2172 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
2173         unsigned char *sha1, const char *base_url)
2174 {
2175         struct packed_git *new_pack;
2176         char *tmp_idx = NULL;
2177         int ret;
2178
2179         if (has_pack_index(sha1)) {
2180                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
2181                 if (!new_pack)
2182                         return -1; /* parse_pack_index() already issued error message */
2183                 goto add_pack;
2184         }
2185
2186         tmp_idx = fetch_pack_index(sha1, base_url);
2187         if (!tmp_idx)
2188                 return -1;
2189
2190         new_pack = parse_pack_index(sha1, tmp_idx);
2191         if (!new_pack) {
2192                 unlink(tmp_idx);
2193                 free(tmp_idx);
2194
2195                 return -1; /* parse_pack_index() already issued error message */
2196         }
2197
2198         ret = verify_pack_index(new_pack);
2199         if (!ret) {
2200                 close_pack_index(new_pack);
2201                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
2202         }
2203         free(tmp_idx);
2204         if (ret)
2205                 return -1;
2206
2207 add_pack:
2208         new_pack->next = *packs_head;
2209         *packs_head = new_pack;
2210         return 0;
2211 }
2212
2213 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
2214 {
2215         struct http_get_options options = {0};
2216         int ret = 0;
2217         char *url;
2218         const char *data;
2219         struct strbuf buf = STRBUF_INIT;
2220         struct object_id oid;
2221
2222         end_url_with_slash(&buf, base_url);
2223         strbuf_addstr(&buf, "objects/info/packs");
2224         url = strbuf_detach(&buf, NULL);
2225
2226         options.no_cache = 1;
2227         ret = http_get_strbuf(url, &buf, &options);
2228         if (ret != HTTP_OK)
2229                 goto cleanup;
2230
2231         data = buf.buf;
2232         while (*data) {
2233                 if (skip_prefix(data, "P pack-", &data) &&
2234                     !parse_oid_hex(data, &oid, &data) &&
2235                     skip_prefix(data, ".pack", &data) &&
2236                     (*data == '\n' || *data == '\0')) {
2237                         fetch_and_setup_pack_index(packs_head, oid.hash, base_url);
2238                 } else {
2239                         data = strchrnul(data, '\n');
2240                 }
2241                 if (*data)
2242                         data++; /* skip past newline */
2243         }
2244
2245 cleanup:
2246         free(url);
2247         return ret;
2248 }
2249
2250 void release_http_pack_request(struct http_pack_request *preq)
2251 {
2252         if (preq->packfile != NULL) {
2253                 fclose(preq->packfile);
2254                 preq->packfile = NULL;
2255         }
2256         preq->slot = NULL;
2257         strbuf_release(&preq->tmpfile);
2258         free(preq->url);
2259         free(preq);
2260 }
2261
2262 static const char *default_index_pack_args[] =
2263         {"index-pack", "--stdin", NULL};
2264
2265 int finish_http_pack_request(struct http_pack_request *preq)
2266 {
2267         struct child_process ip = CHILD_PROCESS_INIT;
2268         int tmpfile_fd;
2269         int ret = 0;
2270
2271         fclose(preq->packfile);
2272         preq->packfile = NULL;
2273
2274         tmpfile_fd = xopen(preq->tmpfile.buf, O_RDONLY);
2275
2276         ip.git_cmd = 1;
2277         ip.in = tmpfile_fd;
2278         ip.argv = preq->index_pack_args ? preq->index_pack_args
2279                                         : default_index_pack_args;
2280
2281         if (preq->preserve_index_pack_stdout)
2282                 ip.out = 0;
2283         else
2284                 ip.no_stdout = 1;
2285
2286         if (run_command(&ip)) {
2287                 ret = -1;
2288                 goto cleanup;
2289         }
2290
2291 cleanup:
2292         close(tmpfile_fd);
2293         unlink(preq->tmpfile.buf);
2294         return ret;
2295 }
2296
2297 void http_install_packfile(struct packed_git *p,
2298                            struct packed_git **list_to_remove_from)
2299 {
2300         struct packed_git **lst = list_to_remove_from;
2301
2302         while (*lst != p)
2303                 lst = &((*lst)->next);
2304         *lst = (*lst)->next;
2305
2306         install_packed_git(the_repository, p);
2307 }
2308
2309 struct http_pack_request *new_http_pack_request(
2310         const unsigned char *packed_git_hash, const char *base_url) {
2311
2312         struct strbuf buf = STRBUF_INIT;
2313
2314         end_url_with_slash(&buf, base_url);
2315         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
2316                 hash_to_hex(packed_git_hash));
2317         return new_direct_http_pack_request(packed_git_hash,
2318                                             strbuf_detach(&buf, NULL));
2319 }
2320
2321 struct http_pack_request *new_direct_http_pack_request(
2322         const unsigned char *packed_git_hash, char *url)
2323 {
2324         off_t prev_posn = 0;
2325         struct http_pack_request *preq;
2326
2327         CALLOC_ARRAY(preq, 1);
2328         strbuf_init(&preq->tmpfile, 0);
2329
2330         preq->url = url;
2331
2332         strbuf_addf(&preq->tmpfile, "%s.temp", sha1_pack_name(packed_git_hash));
2333         preq->packfile = fopen(preq->tmpfile.buf, "a");
2334         if (!preq->packfile) {
2335                 error("Unable to open local file %s for pack",
2336                       preq->tmpfile.buf);
2337                 goto abort;
2338         }
2339
2340         preq->slot = get_active_slot();
2341         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
2342         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
2343         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
2344         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
2345                 no_pragma_header);
2346
2347         /*
2348          * If there is data present from a previous transfer attempt,
2349          * resume where it left off
2350          */
2351         prev_posn = ftello(preq->packfile);
2352         if (prev_posn>0) {
2353                 if (http_is_verbose)
2354                         fprintf(stderr,
2355                                 "Resuming fetch of pack %s at byte %"PRIuMAX"\n",
2356                                 hash_to_hex(packed_git_hash),
2357                                 (uintmax_t)prev_posn);
2358                 http_opt_request_remainder(preq->slot->curl, prev_posn);
2359         }
2360
2361         return preq;
2362
2363 abort:
2364         strbuf_release(&preq->tmpfile);
2365         free(preq->url);
2366         free(preq);
2367         return NULL;
2368 }
2369
2370 /* Helpers for fetching objects (loose) */
2371 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
2372                                void *data)
2373 {
2374         unsigned char expn[4096];
2375         size_t size = eltsize * nmemb;
2376         int posn = 0;
2377         struct http_object_request *freq = data;
2378         struct active_request_slot *slot = freq->slot;
2379
2380         if (slot) {
2381                 CURLcode c = curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE,
2382                                                 &slot->http_code);
2383                 if (c != CURLE_OK)
2384                         BUG("curl_easy_getinfo for HTTP code failed: %s",
2385                                 curl_easy_strerror(c));
2386                 if (slot->http_code >= 300)
2387                         return nmemb;
2388         }
2389
2390         do {
2391                 ssize_t retval = xwrite(freq->localfile,
2392                                         (char *) ptr + posn, size - posn);
2393                 if (retval < 0)
2394                         return posn / eltsize;
2395                 posn += retval;
2396         } while (posn < size);
2397
2398         freq->stream.avail_in = size;
2399         freq->stream.next_in = (void *)ptr;
2400         do {
2401                 freq->stream.next_out = expn;
2402                 freq->stream.avail_out = sizeof(expn);
2403                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
2404                 the_hash_algo->update_fn(&freq->c, expn,
2405                                          sizeof(expn) - freq->stream.avail_out);
2406         } while (freq->stream.avail_in && freq->zret == Z_OK);
2407         return nmemb;
2408 }
2409
2410 struct http_object_request *new_http_object_request(const char *base_url,
2411                                                     const struct object_id *oid)
2412 {
2413         char *hex = oid_to_hex(oid);
2414         struct strbuf filename = STRBUF_INIT;
2415         struct strbuf prevfile = STRBUF_INIT;
2416         int prevlocal;
2417         char prev_buf[PREV_BUF_SIZE];
2418         ssize_t prev_read = 0;
2419         off_t prev_posn = 0;
2420         struct http_object_request *freq;
2421
2422         CALLOC_ARRAY(freq, 1);
2423         strbuf_init(&freq->tmpfile, 0);
2424         oidcpy(&freq->oid, oid);
2425         freq->localfile = -1;
2426
2427         loose_object_path(the_repository, &filename, oid);
2428         strbuf_addf(&freq->tmpfile, "%s.temp", filename.buf);
2429
2430         strbuf_addf(&prevfile, "%s.prev", filename.buf);
2431         unlink_or_warn(prevfile.buf);
2432         rename(freq->tmpfile.buf, prevfile.buf);
2433         unlink_or_warn(freq->tmpfile.buf);
2434         strbuf_release(&filename);
2435
2436         if (freq->localfile != -1)
2437                 error("fd leakage in start: %d", freq->localfile);
2438         freq->localfile = open(freq->tmpfile.buf,
2439                                O_WRONLY | O_CREAT | O_EXCL, 0666);
2440         /*
2441          * This could have failed due to the "lazy directory creation";
2442          * try to mkdir the last path component.
2443          */
2444         if (freq->localfile < 0 && errno == ENOENT) {
2445                 char *dir = strrchr(freq->tmpfile.buf, '/');
2446                 if (dir) {
2447                         *dir = 0;
2448                         mkdir(freq->tmpfile.buf, 0777);
2449                         *dir = '/';
2450                 }
2451                 freq->localfile = open(freq->tmpfile.buf,
2452                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
2453         }
2454
2455         if (freq->localfile < 0) {
2456                 error_errno("Couldn't create temporary file %s",
2457                             freq->tmpfile.buf);
2458                 goto abort;
2459         }
2460
2461         git_inflate_init(&freq->stream);
2462
2463         the_hash_algo->init_fn(&freq->c);
2464
2465         freq->url = get_remote_object_url(base_url, hex, 0);
2466
2467         /*
2468          * If a previous temp file is present, process what was already
2469          * fetched.
2470          */
2471         prevlocal = open(prevfile.buf, O_RDONLY);
2472         if (prevlocal != -1) {
2473                 do {
2474                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
2475                         if (prev_read>0) {
2476                                 if (fwrite_sha1_file(prev_buf,
2477                                                      1,
2478                                                      prev_read,
2479                                                      freq) == prev_read) {
2480                                         prev_posn += prev_read;
2481                                 } else {
2482                                         prev_read = -1;
2483                                 }
2484                         }
2485                 } while (prev_read > 0);
2486                 close(prevlocal);
2487         }
2488         unlink_or_warn(prevfile.buf);
2489         strbuf_release(&prevfile);
2490
2491         /*
2492          * Reset inflate/SHA1 if there was an error reading the previous temp
2493          * file; also rewind to the beginning of the local file.
2494          */
2495         if (prev_read == -1) {
2496                 memset(&freq->stream, 0, sizeof(freq->stream));
2497                 git_inflate_init(&freq->stream);
2498                 the_hash_algo->init_fn(&freq->c);
2499                 if (prev_posn>0) {
2500                         prev_posn = 0;
2501                         lseek(freq->localfile, 0, SEEK_SET);
2502                         if (ftruncate(freq->localfile, 0) < 0) {
2503                                 error_errno("Couldn't truncate temporary file %s",
2504                                             freq->tmpfile.buf);
2505                                 goto abort;
2506                         }
2507                 }
2508         }
2509
2510         freq->slot = get_active_slot();
2511
2512         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
2513         curl_easy_setopt(freq->slot->curl, CURLOPT_FAILONERROR, 0);
2514         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
2515         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
2516         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
2517         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
2518
2519         /*
2520          * If we have successfully processed data from a previous fetch
2521          * attempt, only fetch the data we don't already have.
2522          */
2523         if (prev_posn>0) {
2524                 if (http_is_verbose)
2525                         fprintf(stderr,
2526                                 "Resuming fetch of object %s at byte %"PRIuMAX"\n",
2527                                 hex, (uintmax_t)prev_posn);
2528                 http_opt_request_remainder(freq->slot->curl, prev_posn);
2529         }
2530
2531         return freq;
2532
2533 abort:
2534         strbuf_release(&prevfile);
2535         free(freq->url);
2536         free(freq);
2537         return NULL;
2538 }
2539
2540 void process_http_object_request(struct http_object_request *freq)
2541 {
2542         if (freq->slot == NULL)
2543                 return;
2544         freq->curl_result = freq->slot->curl_result;
2545         freq->http_code = freq->slot->http_code;
2546         freq->slot = NULL;
2547 }
2548
2549 int finish_http_object_request(struct http_object_request *freq)
2550 {
2551         struct stat st;
2552         struct strbuf filename = STRBUF_INIT;
2553
2554         close(freq->localfile);
2555         freq->localfile = -1;
2556
2557         process_http_object_request(freq);
2558
2559         if (freq->http_code == 416) {
2560                 warning("requested range invalid; we may already have all the data.");
2561         } else if (freq->curl_result != CURLE_OK) {
2562                 if (stat(freq->tmpfile.buf, &st) == 0)
2563                         if (st.st_size == 0)
2564                                 unlink_or_warn(freq->tmpfile.buf);
2565                 return -1;
2566         }
2567
2568         git_inflate_end(&freq->stream);
2569         the_hash_algo->final_fn(freq->real_oid.hash, &freq->c);
2570         if (freq->zret != Z_STREAM_END) {
2571                 unlink_or_warn(freq->tmpfile.buf);
2572                 return -1;
2573         }
2574         if (!oideq(&freq->oid, &freq->real_oid)) {
2575                 unlink_or_warn(freq->tmpfile.buf);
2576                 return -1;
2577         }
2578         loose_object_path(the_repository, &filename, &freq->oid);
2579         freq->rename = finalize_object_file(freq->tmpfile.buf, filename.buf);
2580         strbuf_release(&filename);
2581
2582         return freq->rename;
2583 }
2584
2585 void abort_http_object_request(struct http_object_request *freq)
2586 {
2587         unlink_or_warn(freq->tmpfile.buf);
2588
2589         release_http_object_request(freq);
2590 }
2591
2592 void release_http_object_request(struct http_object_request *freq)
2593 {
2594         if (freq->localfile != -1) {
2595                 close(freq->localfile);
2596                 freq->localfile = -1;
2597         }
2598         FREE_AND_NULL(freq->url);
2599         if (freq->slot != NULL) {
2600                 freq->slot->callback_func = NULL;
2601                 freq->slot->callback_data = NULL;
2602                 release_active_slot(freq->slot);
2603                 freq->slot = NULL;
2604         }
2605         strbuf_release(&freq->tmpfile);
2606 }