git.oblomov.eu Git - git/blob - http-push.c

   1 #include "cache.h"
   2 #include "commit.h"
   3 #include "pack.h"
   4 #include "fetch.h"
   5 #include "tag.h"
   6 #include "blob.h"
   7 #include "http.h"
   8
   9 #include <expat.h>
  10
  11 static const char http_push_usage[] =
  12 "git-http-push [--complete] [--force] [--verbose] <url> <ref> [<ref>...]\n";
  13
  14 #ifndef XML_STATUS_OK
  15 enum XML_Status {
  16   XML_STATUS_OK = 1,
  17   XML_STATUS_ERROR = 0
  18 };
  19 #define XML_STATUS_OK    1
  20 #define XML_STATUS_ERROR 0
  21 #endif
  22
  23 #define RANGE_HEADER_SIZE 30
  24
  25 /* DAV methods */
  26 #define DAV_LOCK "LOCK"
  27 #define DAV_MKCOL "MKCOL"
  28 #define DAV_MOVE "MOVE"
  29 #define DAV_PROPFIND "PROPFIND"
  30 #define DAV_PUT "PUT"
  31 #define DAV_UNLOCK "UNLOCK"
  32
  33 /* DAV lock flags */
  34 #define DAV_PROP_LOCKWR (1u << 0)
  35 #define DAV_PROP_LOCKEX (1u << 1)
  36 #define DAV_LOCK_OK (1u << 2)
  37
  38 /* DAV XML properties */
  39 #define DAV_CTX_LOCKENTRY ".multistatus.response.propstat.prop.supportedlock.lockentry"
  40 #define DAV_CTX_LOCKTYPE_WRITE ".multistatus.response.propstat.prop.supportedlock.lockentry.locktype.write"
  41 #define DAV_CTX_LOCKTYPE_EXCLUSIVE ".multistatus.response.propstat.prop.supportedlock.lockentry.lockscope.exclusive"
  42 #define DAV_ACTIVELOCK_OWNER ".prop.lockdiscovery.activelock.owner.href"
  43 #define DAV_ACTIVELOCK_TIMEOUT ".prop.lockdiscovery.activelock.timeout"
  44 #define DAV_ACTIVELOCK_TOKEN ".prop.lockdiscovery.activelock.locktoken.href"
  45
  46 /* DAV request body templates */
  47 #define PROPFIND_REQUEST "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:propfind xmlns:D=\"DAV:\">\n<D:prop xmlns:R=\"%s\">\n<D:supportedlock/>\n</D:prop>\n</D:propfind>"
  48 #define LOCK_REQUEST "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:lockinfo xmlns:D=\"DAV:\">\n<D:lockscope><D:exclusive/></D:lockscope>\n<D:locktype><D:write/></D:locktype>\n<D:owner>\n<D:href>mailto:%s</D:href>\n</D:owner>\n</D:lockinfo>"
  49
  50 #define LOCK_TIME 600
  51 #define LOCK_REFRESH 30
  52
  53 static int pushing = 0;
  54 static int aborted = 0;
  55 static char remote_dir_exists[256];
  56
  57 static struct curl_slist *no_pragma_header;
  58 static struct curl_slist *default_headers;
  59
  60 static int push_verbosely = 0;
  61 static int push_all = 0;
  62 static int force_all = 0;
  63
  64 struct repo
  65 {
  66         char *url;
  67         struct packed_git *packs;
  68 };
  69
  70 static struct repo *remote = NULL;
  71
  72 enum transfer_state {
  73         NEED_CHECK,
  74         RUN_HEAD,
  75         NEED_PUSH,
  76         RUN_MKCOL,
  77         RUN_PUT,
  78         RUN_MOVE,
  79         ABORTED,
  80         COMPLETE,
  81 };
  82
  83 struct transfer_request
  84 {
  85         unsigned char sha1[20];
  86         char *url;
  87         char *dest;
  88         struct active_lock *lock;
  89         struct curl_slist *headers;
  90         struct buffer buffer;
  91         char filename[PATH_MAX];
  92         char tmpfile[PATH_MAX];
  93         enum transfer_state state;
  94         CURLcode curl_result;
  95         char errorstr[CURL_ERROR_SIZE];
  96         long http_code;
  97         unsigned char real_sha1[20];
  98         SHA_CTX c;
  99         z_stream stream;
 100         int zret;
 101         int rename;
 102         struct active_request_slot *slot;
 103         struct transfer_request *next;
 104 };
 105
 106 static struct transfer_request *request_queue_head = NULL;
 107
 108 struct xml_ctx
 109 {
 110         char *name;
 111         int len;
 112         char *cdata;
 113         void (*userFunc)(struct xml_ctx *ctx, int tag_closed);
 114         void *userData;
 115 };
 116
 117 struct active_lock
 118 {
 119         char *url;
 120         char *owner;
 121         char *token;
 122         time_t start_time;
 123         long timeout;
 124         int refreshing;
 125 };
 126
 127 static void finish_request(struct transfer_request *request);
 128
 129 static void process_response(void *callback_data)
 130 {
 131         struct transfer_request *request =
 132                 (struct transfer_request *)callback_data;
 133
 134         finish_request(request);
 135 }
 136
 137 static void start_check(struct transfer_request *request)
 138 {
 139         char *hex = sha1_to_hex(request->sha1);
 140         struct active_request_slot *slot;
 141         char *posn;
 142
 143         request->url = xmalloc(strlen(remote->url) + 55);
 144         strcpy(request->url, remote->url);
 145         posn = request->url + strlen(remote->url);
 146         strcpy(posn, "objects/");
 147         posn += 8;
 148         memcpy(posn, hex, 2);
 149         posn += 2;
 150         *(posn++) = '/';
 151         strcpy(posn, hex + 2);
 152
 153         slot = get_active_slot();
 154         slot->callback_func = process_response;
 155         slot->callback_data = request;
 156         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, request->errorstr);
 157         curl_easy_setopt(slot->curl, CURLOPT_URL, request->url);
 158         curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
 159
 160         if (start_active_slot(slot)) {
 161                 request->slot = slot;
 162                 request->state = RUN_HEAD;
 163         } else {
 164                 request->state = ABORTED;
 165                 free(request->url);
 166                 request->url = NULL;
 167         }
 168 }
 169
 170 static void start_mkcol(struct transfer_request *request)
 171 {
 172         char *hex = sha1_to_hex(request->sha1);
 173         struct active_request_slot *slot;
 174         char *posn;
 175
 176         request->url = xmalloc(strlen(remote->url) + 13);
 177         strcpy(request->url, remote->url);
 178         posn = request->url + strlen(remote->url);
 179         strcpy(posn, "objects/");
 180         posn += 8;
 181         memcpy(posn, hex, 2);
 182         posn += 2;
 183         strcpy(posn, "/");
 184
 185         slot = get_active_slot();
 186         slot->callback_func = process_response;
 187         slot->callback_data = request;
 188         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1); /* undo PUT setup */
 189         curl_easy_setopt(slot->curl, CURLOPT_URL, request->url);
 190         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, request->errorstr);
 191         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, DAV_MKCOL);
 192         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_null);
 193
 194         if (start_active_slot(slot)) {
 195                 request->slot = slot;
 196                 request->state = RUN_MKCOL;
 197         } else {
 198                 request->state = ABORTED;
 199                 free(request->url);
 200                 request->url = NULL;
 201         }
 202 }
 203
 204 static void start_put(struct transfer_request *request)
 205 {
 206         char *hex = sha1_to_hex(request->sha1);
 207         struct active_request_slot *slot;
 208         char *posn;
 209         char type[20];
 210         char hdr[50];
 211         void *unpacked;
 212         unsigned long len;
 213         int hdrlen;
 214         ssize_t size;
 215         z_stream stream;
 216
 217         unpacked = read_sha1_file(request->sha1, type, &len);
 218         hdrlen = sprintf(hdr, "%s %lu", type, len) + 1;
 219
 220         /* Set it up */
 221         memset(&stream, 0, sizeof(stream));
 222         deflateInit(&stream, Z_BEST_COMPRESSION);
 223         size = deflateBound(&stream, len + hdrlen);
 224         request->buffer.buffer = xmalloc(size);
 225
 226         /* Compress it */
 227         stream.next_out = request->buffer.buffer;
 228         stream.avail_out = size;
 229
 230         /* First header.. */
 231         stream.next_in = (void *)hdr;
 232         stream.avail_in = hdrlen;
 233         while (deflate(&stream, 0) == Z_OK)
 234                 /* nothing */;
 235
 236         /* Then the data itself.. */
 237         stream.next_in = unpacked;
 238         stream.avail_in = len;
 239         while (deflate(&stream, Z_FINISH) == Z_OK)
 240                 /* nothing */;
 241         deflateEnd(&stream);
 242         free(unpacked);
 243
 244         request->buffer.size = stream.total_out;
 245         request->buffer.posn = 0;
 246
 247         request->url = xmalloc(strlen(remote->url) +
 248                                strlen(request->lock->token) + 51);
 249         strcpy(request->url, remote->url);
 250         posn = request->url + strlen(remote->url);
 251         strcpy(posn, "objects/");
 252         posn += 8;
 253         memcpy(posn, hex, 2);
 254         posn += 2;
 255         *(posn++) = '/';
 256         strcpy(posn, hex + 2);
 257         request->dest = xmalloc(strlen(request->url) + 14);
 258         sprintf(request->dest, "Destination: %s", request->url);
 259         posn += 38;
 260         *(posn++) = '.';
 261         strcpy(posn, request->lock->token);
 262
 263         slot = get_active_slot();
 264         slot->callback_func = process_response;
 265         slot->callback_data = request;
 266         curl_easy_setopt(slot->curl, CURLOPT_INFILE, &request->buffer);
 267         curl_easy_setopt(slot->curl, CURLOPT_INFILESIZE, request->buffer.size);
 268         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, fread_buffer);
 269         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_null);
 270         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, DAV_PUT);
 271         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 1);
 272         curl_easy_setopt(slot->curl, CURLOPT_PUT, 1);
 273         curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 274         curl_easy_setopt(slot->curl, CURLOPT_URL, request->url);
 275
 276         if (start_active_slot(slot)) {
 277                 request->slot = slot;
 278                 request->state = RUN_PUT;
 279         } else {
 280                 request->state = ABORTED;
 281                 free(request->url);
 282                 request->url = NULL;
 283         }
 284 }
 285
 286 static void start_move(struct transfer_request *request)
 287 {
 288         struct active_request_slot *slot;
 289         struct curl_slist *dav_headers = NULL;
 290
 291         slot = get_active_slot();
 292         slot->callback_func = process_response;
 293         slot->callback_data = request;
 294         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1); /* undo PUT setup */
 295         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, DAV_MOVE);
 296         dav_headers = curl_slist_append(dav_headers, request->dest);
 297         dav_headers = curl_slist_append(dav_headers, "Overwrite: T");
 298         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, dav_headers);
 299         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_null);
 300         curl_easy_setopt(slot->curl, CURLOPT_URL, request->url);
 301
 302         if (start_active_slot(slot)) {
 303                 request->slot = slot;
 304                 request->state = RUN_MOVE;
 305         } else {
 306                 request->state = ABORTED;
 307                 free(request->url);
 308                 request->url = NULL;
 309         }
 310 }
 311
 312 static int refresh_lock(struct active_lock *lock)
 313 {
 314         struct active_request_slot *slot;
 315         char *if_header;
 316         char timeout_header[25];
 317         struct curl_slist *dav_headers = NULL;
 318         int rc = 0;
 319
 320         lock->refreshing = 1;
 321
 322         if_header = xmalloc(strlen(lock->token) + 25);
 323         sprintf(if_header, "If: (<opaquelocktoken:%s>)", lock->token);
 324         sprintf(timeout_header, "Timeout: Second-%ld", lock->timeout);
 325         dav_headers = curl_slist_append(dav_headers, if_header);
 326         dav_headers = curl_slist_append(dav_headers, timeout_header);
 327
 328         slot = get_active_slot();
 329         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 330         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_null);
 331         curl_easy_setopt(slot->curl, CURLOPT_URL, lock->url);
 332         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, DAV_LOCK);
 333         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, dav_headers);
 334
 335         if (start_active_slot(slot)) {
 336                 run_active_slot(slot);
 337                 if (slot->curl_result != CURLE_OK) {
 338                         fprintf(stderr, "Got HTTP error %ld\n", slot->http_code);
 339                 } else {
 340                         lock->start_time = time(NULL);
 341                         rc = 1;
 342                 }
 343         }
 344
 345         lock->refreshing = 0;
 346         curl_slist_free_all(dav_headers);
 347         free(if_header);
 348
 349         return rc;
 350 }
 351
 352 static void finish_request(struct transfer_request *request)
 353 {
 354         time_t current_time = time(NULL);
 355         int time_remaining;
 356
 357         request->curl_result =  request->slot->curl_result;
 358         request->http_code = request->slot->http_code;
 359         request->slot = NULL;
 360
 361         /* Refresh the lock if it is close to timing out */
 362         time_remaining = request->lock->start_time + request->lock->timeout
 363                 - current_time;
 364         if (time_remaining < LOCK_REFRESH && !request->lock->refreshing) {
 365                 if (!refresh_lock(request->lock)) {
 366                         fprintf(stderr, "Unable to refresh remote lock\n");
 367                         aborted = 1;
 368                 }
 369         }
 370
 371         if (request->headers != NULL)
 372                 curl_slist_free_all(request->headers);
 373
 374         /* URL is reused for MOVE after PUT */
 375         if (request->state != RUN_PUT) {
 376                 free(request->url);
 377                 request->url = NULL;
 378         }
 379
 380         if (request->state == RUN_HEAD) {
 381                 if (request->http_code == 404) {
 382                         request->state = NEED_PUSH;
 383                 } else if (request->curl_result == CURLE_OK) {
 384                         remote_dir_exists[request->sha1[0]] = 1;
 385                         request->state = COMPLETE;
 386                 } else {
 387                         fprintf(stderr, "HEAD %s failed, aborting (%d/%ld)\n",
 388                                 sha1_to_hex(request->sha1),
 389                                 request->curl_result, request->http_code);
 390                         request->state = ABORTED;
 391                         aborted = 1;
 392                 }
 393         } else if (request->state == RUN_MKCOL) {
 394                 if (request->curl_result == CURLE_OK ||
 395                     request->http_code == 405) {
 396                         remote_dir_exists[request->sha1[0]] = 1;
 397                         start_put(request);
 398                 } else {
 399                         fprintf(stderr, "MKCOL %s failed, aborting (%d/%ld)\n",
 400                                 sha1_to_hex(request->sha1),
 401                                 request->curl_result, request->http_code);
 402                         request->state = ABORTED;
 403                         aborted = 1;
 404                 }
 405         } else if (request->state == RUN_PUT) {
 406                 if (request->curl_result == CURLE_OK) {
 407                         start_move(request);
 408                 } else {
 409                         fprintf(stderr, "PUT %s failed, aborting (%d/%ld)\n",
 410                                 sha1_to_hex(request->sha1),
 411                                 request->curl_result, request->http_code);
 412                         request->state = ABORTED;
 413                         aborted = 1;
 414                 }
 415         } else if (request->state == RUN_MOVE) {
 416                 if (request->curl_result == CURLE_OK) {
 417                         if (push_verbosely)
 418                                 fprintf(stderr,
 419                                         "sent %s\n",
 420                                         sha1_to_hex(request->sha1));
 421                         request->state = COMPLETE;
 422                 } else {
 423                         fprintf(stderr, "MOVE %s failed, aborting (%d/%ld)\n",
 424                                 sha1_to_hex(request->sha1),
 425                                 request->curl_result, request->http_code);
 426                         request->state = ABORTED;
 427                         aborted = 1;
 428                 }
 429         }
 430 }
 431
 432 static void release_request(struct transfer_request *request)
 433 {
 434         struct transfer_request *entry = request_queue_head;
 435
 436         if (request == request_queue_head) {
 437                 request_queue_head = request->next;
 438         } else {
 439                 while (entry->next != NULL && entry->next != request)
 440                         entry = entry->next;
 441                 if (entry->next == request)
 442                         entry->next = entry->next->next;
 443         }
 444
 445         if (request->url != NULL)
 446                 free(request->url);
 447         free(request);
 448 }
 449
 450 void fill_active_slots(void)
 451 {
 452         struct transfer_request *request = request_queue_head;
 453         struct active_request_slot *slot = active_queue_head;
 454         int num_transfers;
 455
 456         if (aborted)
 457                 return;
 458
 459         while (active_requests < max_requests && request != NULL) {
 460                 if (!pushing && request->state == NEED_CHECK) {
 461                         start_check(request);
 462                         curl_multi_perform(curlm, &num_transfers);
 463                 } else if (pushing && request->state == NEED_PUSH) {
 464                         if (remote_dir_exists[request->sha1[0]])
 465                                 start_put(request);
 466                         else
 467                                 start_mkcol(request);
 468                         curl_multi_perform(curlm, &num_transfers);
 469                 }
 470                 request = request->next;
 471         }
 472
 473         while (slot != NULL) {
 474                 if (!slot->in_use && slot->curl != NULL) {
 475                         curl_easy_cleanup(slot->curl);
 476                         slot->curl = NULL;
 477                 }
 478                 slot = slot->next;
 479         }
 480 }
 481
 482 static void add_request(unsigned char *sha1, struct active_lock *lock)
 483 {
 484         struct transfer_request *request = request_queue_head;
 485         struct packed_git *target;
 486
 487         while (request != NULL && memcmp(request->sha1, sha1, 20))
 488                 request = request->next;
 489         if (request != NULL)
 490                 return;
 491
 492         target = find_sha1_pack(sha1, remote->packs);
 493         if (target)
 494                 return;
 495
 496         request = xmalloc(sizeof(*request));
 497         memcpy(request->sha1, sha1, 20);
 498         request->url = NULL;
 499         request->lock = lock;
 500         request->headers = NULL;
 501         request->state = NEED_CHECK;
 502         request->next = request_queue_head;
 503         request_queue_head = request;
 504
 505         fill_active_slots();
 506         step_active_slots();
 507 }
 508
 509 static int fetch_index(unsigned char *sha1)
 510 {
 511         char *hex = sha1_to_hex(sha1);
 512         char *filename;
 513         char *url;
 514         char tmpfile[PATH_MAX];
 515         long prev_posn = 0;
 516         char range[RANGE_HEADER_SIZE];
 517         struct curl_slist *range_header = NULL;
 518
 519         FILE *indexfile;
 520         struct active_request_slot *slot;
 521
 522         /* Don't use the index if the pack isn't there */
 523         url = xmalloc(strlen(remote->url) + 65);
 524         sprintf(url, "%s/objects/pack/pack-%s.pack", remote->url, hex);
 525         slot = get_active_slot();
 526         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 527         curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
 528         if (start_active_slot(slot)) {
 529                 run_active_slot(slot);
 530                 if (slot->curl_result != CURLE_OK) {
 531                         free(url);
 532                         return error("Unable to verify pack %s is available",
 533                                      hex);
 534                 }
 535         } else {
 536                 return error("Unable to start request");
 537         }
 538
 539         if (has_pack_index(sha1))
 540                 return 0;
 541
 542         if (push_verbosely)
 543                 fprintf(stderr, "Getting index for pack %s\n", hex);
 544
 545         sprintf(url, "%s/objects/pack/pack-%s.idx", remote->url, hex);
 546
 547         filename = sha1_pack_index_name(sha1);
 548         snprintf(tmpfile, sizeof(tmpfile), "%s.temp", filename);
 549         indexfile = fopen(tmpfile, "a");
 550         if (!indexfile)
 551                 return error("Unable to open local file %s for pack index",
 552                              filename);
 553
 554         slot = get_active_slot();
 555         curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
 556         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 557         curl_easy_setopt(slot->curl, CURLOPT_FILE, indexfile);
 558         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
 559         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 560         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
 561         slot->local = indexfile;
 562
 563         /* If there is data present from a previous transfer attempt,
 564            resume where it left off */
 565         prev_posn = ftell(indexfile);
 566         if (prev_posn>0) {
 567                 if (push_verbosely)
 568                         fprintf(stderr,
 569                                 "Resuming fetch of index for pack %s at byte %ld\n",
 570                                 hex, prev_posn);
 571                 sprintf(range, "Range: bytes=%ld-", prev_posn);
 572                 range_header = curl_slist_append(range_header, range);
 573                 curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, range_header);
 574         }
 575
 576         if (start_active_slot(slot)) {
 577                 run_active_slot(slot);
 578                 if (slot->curl_result != CURLE_OK) {
 579                         free(url);
 580                         fclose(indexfile);
 581                         return error("Unable to get pack index %s\n%s", url,
 582                                      curl_errorstr);
 583                 }
 584         } else {
 585                 free(url);
 586                 fclose(indexfile);
 587                 return error("Unable to start request");
 588         }
 589
 590         free(url);
 591         fclose(indexfile);
 592
 593         return move_temp_to_file(tmpfile, filename);
 594 }
 595
 596 static int setup_index(unsigned char *sha1)
 597 {
 598         struct packed_git *new_pack;
 599
 600         if (fetch_index(sha1))
 601                 return -1;
 602
 603         new_pack = parse_pack_index(sha1);
 604         new_pack->next = remote->packs;
 605         remote->packs = new_pack;
 606         return 0;
 607 }
 608
 609 static int fetch_indices(void)
 610 {
 611         unsigned char sha1[20];
 612         char *url;
 613         struct buffer buffer;
 614         char *data;
 615         int i = 0;
 616
 617         struct active_request_slot *slot;
 618
 619         data = xmalloc(4096);
 620         memset(data, 0, 4096);
 621         buffer.size = 4096;
 622         buffer.posn = 0;
 623         buffer.buffer = data;
 624
 625         if (push_verbosely)
 626                 fprintf(stderr, "Getting pack list\n");
 627
 628         url = xmalloc(strlen(remote->url) + 21);
 629         sprintf(url, "%s/objects/info/packs", remote->url);
 630
 631         slot = get_active_slot();
 632         curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 633         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 634         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 635         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
 636         if (start_active_slot(slot)) {
 637                 run_active_slot(slot);
 638                 if (slot->curl_result != CURLE_OK) {
 639                         free(buffer.buffer);
 640                         free(url);
 641                         if (slot->http_code == 404)
 642                                 return 0;
 643                         else
 644                                 return error("%s", curl_errorstr);
 645                 }
 646         } else {
 647                 free(buffer.buffer);
 648                 free(url);
 649                 return error("Unable to start request");
 650         }
 651         free(url);
 652
 653         data = buffer.buffer;
 654         while (i < buffer.posn) {
 655                 switch (data[i]) {
 656                 case 'P':
 657                         i++;
 658                         if (i + 52 < buffer.posn &&
 659                             !strncmp(data + i, " pack-", 6) &&
 660                             !strncmp(data + i + 46, ".pack\n", 6)) {
 661                                 get_sha1_hex(data + i + 6, sha1);
 662                                 setup_index(sha1);
 663                                 i += 51;
 664                                 break;
 665                         }
 666                 default:
 667                         while (data[i] != '\n')
 668                                 i++;
 669                 }
 670                 i++;
 671         }
 672
 673         free(buffer.buffer);
 674         return 0;
 675 }
 676
 677 static inline int needs_quote(int ch)
 678 {
 679         switch (ch) {
 680         case '/': case '-': case '.':
 681         case 'A'...'Z': case 'a'...'z': case '0'...'9':
 682                 return 0;
 683         default:
 684                 return 1;
 685         }
 686 }
 687
 688 static inline int hex(int v)
 689 {
 690         if (v < 10) return '0' + v;
 691         else return 'A' + v - 10;
 692 }
 693
 694 static char *quote_ref_url(const char *base, const char *ref)
 695 {
 696         const char *cp;
 697         char *dp, *qref;
 698         int len, baselen, ch;
 699
 700         baselen = strlen(base);
 701         len = baselen + 12; /* "refs/heads/" + NUL */
 702         for (cp = ref; (ch = *cp) != 0; cp++, len++)
 703                 if (needs_quote(ch))
 704                         len += 2; /* extra two hex plus replacement % */
 705         qref = xmalloc(len);
 706         memcpy(qref, base, baselen);
 707         memcpy(qref + baselen, "refs/heads/", 11);
 708         for (cp = ref, dp = qref + baselen + 11; (ch = *cp) != 0; cp++) {
 709                 if (needs_quote(ch)) {
 710                         *dp++ = '%';
 711                         *dp++ = hex((ch >> 4) & 0xF);
 712                         *dp++ = hex(ch & 0xF);
 713                 }
 714                 else
 715                         *dp++ = ch;
 716         }
 717         *dp = 0;
 718
 719         return qref;
 720 }
 721
 722 int fetch_ref(char *ref, unsigned char *sha1)
 723 {
 724         char *url;
 725         char hex[42];
 726         struct buffer buffer;
 727         char *base = remote->url;
 728         struct active_request_slot *slot;
 729         buffer.size = 41;
 730         buffer.posn = 0;
 731         buffer.buffer = hex;
 732         hex[41] = '\0';
 733
 734         url = quote_ref_url(base, ref);
 735         slot = get_active_slot();
 736         curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 737         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 738         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
 739         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 740         if (start_active_slot(slot)) {
 741                 run_active_slot(slot);
 742                 if (slot->curl_result != CURLE_OK)
 743                         return error("Couldn't get %s for %s\n%s",
 744                                      url, ref, curl_errorstr);
 745         } else {
 746                 return error("Unable to start request");
 747         }
 748
 749         hex[40] = '\0';
 750         get_sha1_hex(hex, sha1);
 751         return 0;
 752 }
 753
 754 static void handle_lockprop_ctx(struct xml_ctx *ctx, int tag_closed)
 755 {
 756         int *lock_flags = (int *)ctx->userData;
 757
 758         if (tag_closed) {
 759                 if (!strcmp(ctx->name, DAV_CTX_LOCKENTRY)) {
 760                         if ((*lock_flags & DAV_PROP_LOCKEX) &&
 761                             (*lock_flags & DAV_PROP_LOCKWR)) {
 762                                 *lock_flags |= DAV_LOCK_OK;
 763                         }
 764                         *lock_flags &= DAV_LOCK_OK;
 765                 } else if (!strcmp(ctx->name, DAV_CTX_LOCKTYPE_WRITE)) {
 766                         *lock_flags |= DAV_PROP_LOCKWR;
 767                 } else if (!strcmp(ctx->name, DAV_CTX_LOCKTYPE_EXCLUSIVE)) {
 768                         *lock_flags |= DAV_PROP_LOCKEX;
 769                 }
 770         }
 771 }
 772
 773 static void handle_new_lock_ctx(struct xml_ctx *ctx, int tag_closed)
 774 {
 775         struct active_lock *lock = (struct active_lock *)ctx->userData;
 776
 777         if (tag_closed && ctx->cdata) {
 778                 if (!strcmp(ctx->name, DAV_ACTIVELOCK_OWNER)) {
 779                         lock->owner = xmalloc(strlen(ctx->cdata) + 1);
 780                         strcpy(lock->owner, ctx->cdata);
 781                 } else if (!strcmp(ctx->name, DAV_ACTIVELOCK_TIMEOUT)) {
 782                         if (!strncmp(ctx->cdata, "Second-", 7))
 783                                 lock->timeout =
 784                                         strtol(ctx->cdata + 7, NULL, 10);
 785                 } else if (!strcmp(ctx->name, DAV_ACTIVELOCK_TOKEN)) {
 786                         if (!strncmp(ctx->cdata, "opaquelocktoken:", 16)) {
 787                                 lock->token = xmalloc(strlen(ctx->cdata) - 15);
 788                                 strcpy(lock->token, ctx->cdata + 16);
 789                         }
 790                 }
 791         }
 792 }
 793
 794 static void
 795 xml_start_tag(void *userData, const char *name, const char **atts)
 796 {
 797         struct xml_ctx *ctx = (struct xml_ctx *)userData;
 798         const char *c = index(name, ':');
 799         int new_len;
 800
 801         if (c == NULL)
 802                 c = name;
 803         else
 804                 c++;
 805
 806         new_len = strlen(ctx->name) + strlen(c) + 2;
 807
 808         if (new_len > ctx->len) {
 809                 ctx->name = xrealloc(ctx->name, new_len);
 810                 ctx->len = new_len;
 811         }
 812         strcat(ctx->name, ".");
 813         strcat(ctx->name, c);
 814
 815         if (ctx->cdata) {
 816                 free(ctx->cdata);
 817                 ctx->cdata = NULL;
 818         }
 819
 820         ctx->userFunc(ctx, 0);
 821 }
 822
 823 static void
 824 xml_end_tag(void *userData, const char *name)
 825 {
 826         struct xml_ctx *ctx = (struct xml_ctx *)userData;
 827         const char *c = index(name, ':');
 828         char *ep;
 829
 830         ctx->userFunc(ctx, 1);
 831
 832         if (c == NULL)
 833                 c = name;
 834         else
 835                 c++;
 836
 837         ep = ctx->name + strlen(ctx->name) - strlen(c) - 1;
 838         *ep = 0;
 839 }
 840
 841 static void
 842 xml_cdata(void *userData, const XML_Char *s, int len)
 843 {
 844         struct xml_ctx *ctx = (struct xml_ctx *)userData;
 845         if (ctx->cdata)
 846                 free(ctx->cdata);
 847         ctx->cdata = xcalloc(len+1, 1);
 848         strncpy(ctx->cdata, s, len);
 849 }
 850
 851 static struct active_lock *lock_remote(char *file, long timeout)
 852 {
 853         struct active_request_slot *slot;
 854         struct buffer out_buffer;
 855         struct buffer in_buffer;
 856         char *out_data;
 857         char *in_data;
 858         char *url;
 859         char *ep;
 860         char timeout_header[25];
 861         struct active_lock *new_lock = NULL;
 862         XML_Parser parser = XML_ParserCreate(NULL);
 863         enum XML_Status result;
 864         struct curl_slist *dav_headers = NULL;
 865         struct xml_ctx ctx;
 866
 867         url = xmalloc(strlen(remote->url) + strlen(file) + 1);
 868         sprintf(url, "%s%s", remote->url, file);
 869
 870         /* Make sure leading directories exist for the remote ref */
 871         ep = strchr(url + strlen(remote->url) + 11, '/');
 872         while (ep) {
 873                 *ep = 0;
 874                 slot = get_active_slot();
 875                 curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 876                 curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 877                 curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, DAV_MKCOL);
 878                 curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_null);
 879                 if (start_active_slot(slot)) {
 880                         run_active_slot(slot);
 881                         if (slot->curl_result != CURLE_OK &&
 882                             slot->http_code != 405) {
 883                                 fprintf(stderr,
 884                                         "Unable to create branch path %s\n",
 885                                         url);
 886                                 free(url);
 887                                 return NULL;
 888                         }
 889                 } else {
 890                         fprintf(stderr, "Unable to start request\n");
 891                         free(url);
 892                         return NULL;
 893                 }
 894                 *ep = '/';
 895                 ep = strchr(ep + 1, '/');
 896         }
 897
 898         out_buffer.size = strlen(LOCK_REQUEST) + strlen(git_default_email) - 2;
 899         out_data = xmalloc(out_buffer.size + 1);
 900         snprintf(out_data, out_buffer.size + 1, LOCK_REQUEST, git_default_email);
 901         out_buffer.posn = 0;
 902         out_buffer.buffer = out_data;
 903
 904         in_buffer.size = 4096;
 905         in_data = xmalloc(in_buffer.size);
 906         in_buffer.posn = 0;
 907         in_buffer.buffer = in_data;
 908
 909         sprintf(timeout_header, "Timeout: Second-%ld", timeout);
 910         dav_headers = curl_slist_append(dav_headers, timeout_header);
 911         dav_headers = curl_slist_append(dav_headers, "Content-Type: text/xml");
 912
 913         slot = get_active_slot();
 914         curl_easy_setopt(slot->curl, CURLOPT_INFILE, &out_buffer);
 915         curl_easy_setopt(slot->curl, CURLOPT_INFILESIZE, out_buffer.size);
 916         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, fread_buffer);
 917         curl_easy_setopt(slot->curl, CURLOPT_FILE, &in_buffer);
 918         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 919         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
 920         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 1);
 921         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, DAV_LOCK);
 922         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, dav_headers);
 923
 924         new_lock = xcalloc(1, sizeof(*new_lock));
 925         new_lock->owner = NULL;
 926         new_lock->token = NULL;
 927         new_lock->timeout = -1;
 928         new_lock->refreshing = 0;
 929
 930         if (start_active_slot(slot)) {
 931                 run_active_slot(slot);
 932                 if (slot->curl_result == CURLE_OK) {
 933                         ctx.name = xcalloc(10, 1);
 934                         ctx.len = 0;
 935                         ctx.cdata = NULL;
 936                         ctx.userFunc = handle_new_lock_ctx;
 937                         ctx.userData = new_lock;
 938                         XML_SetUserData(parser, &ctx);
 939                         XML_SetElementHandler(parser, xml_start_tag,
 940                                               xml_end_tag);
 941                         XML_SetCharacterDataHandler(parser, xml_cdata);
 942                         result = XML_Parse(parser, in_buffer.buffer,
 943                                            in_buffer.posn, 1);
 944                         free(ctx.name);
 945                         if (result != XML_STATUS_OK) {
 946                                 fprintf(stderr, "XML error: %s\n",
 947                                         XML_ErrorString(
 948                                                 XML_GetErrorCode(parser)));
 949                                 new_lock->timeout = -1;
 950                         }
 951                 }
 952         } else {
 953                 fprintf(stderr, "Unable to start request\n");
 954         }
 955
 956         curl_slist_free_all(dav_headers);
 957         free(out_data);
 958         free(in_data);
 959
 960         if (new_lock->token == NULL || new_lock->timeout <= 0) {
 961                 if (new_lock->token != NULL)
 962                         free(new_lock->token);
 963                 if (new_lock->owner != NULL)
 964                         free(new_lock->owner);
 965                 free(url);
 966                 free(new_lock);
 967                 new_lock = NULL;
 968         } else {
 969                 new_lock->url = url;
 970                 new_lock->start_time = time(NULL);
 971         }
 972
 973         return new_lock;
 974 }
 975
 976 static int unlock_remote(struct active_lock *lock)
 977 {
 978         struct active_request_slot *slot;
 979         char *lock_token_header;
 980         struct curl_slist *dav_headers = NULL;
 981         int rc = 0;
 982
 983         lock_token_header = xmalloc(strlen(lock->token) + 31);
 984         sprintf(lock_token_header, "Lock-Token: <opaquelocktoken:%s>",
 985                 lock->token);
 986         dav_headers = curl_slist_append(dav_headers, lock_token_header);
 987
 988         slot = get_active_slot();
 989         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_null);
 990         curl_easy_setopt(slot->curl, CURLOPT_URL, lock->url);
 991         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, DAV_UNLOCK);
 992         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, dav_headers);
 993
 994         if (start_active_slot(slot)) {
 995                 run_active_slot(slot);
 996                 if (slot->curl_result == CURLE_OK)
 997                         rc = 1;
 998                 else
 999                         fprintf(stderr, "Got HTTP error %ld\n",
1000                                 slot->http_code);
1001         } else {
1002                 fprintf(stderr, "Unable to start request\n");
1003         }
1004
1005         curl_slist_free_all(dav_headers);
1006         free(lock_token_header);
1007
1008         if (lock->owner != NULL)
1009                 free(lock->owner);
1010         free(lock->url);
1011         free(lock->token);
1012         free(lock);
1013
1014         return rc;
1015 }
1016
1017 static int locking_available(void)
1018 {
1019         struct active_request_slot *slot;
1020         struct buffer in_buffer;
1021         struct buffer out_buffer;
1022         char *in_data;
1023         char *out_data;
1024         XML_Parser parser = XML_ParserCreate(NULL);
1025         enum XML_Status result;
1026         struct curl_slist *dav_headers = NULL;
1027         struct xml_ctx ctx;
1028         int lock_flags = 0;
1029
1030         out_buffer.size = strlen(PROPFIND_REQUEST) + strlen(remote->url) - 2;
1031         out_data = xmalloc(out_buffer.size + 1);
1032         snprintf(out_data, out_buffer.size + 1, PROPFIND_REQUEST, remote->url);
1033         out_buffer.posn = 0;
1034         out_buffer.buffer = out_data;
1035
1036         in_buffer.size = 4096;
1037         in_data = xmalloc(in_buffer.size);
1038         in_buffer.posn = 0;
1039         in_buffer.buffer = in_data;
1040
1041         dav_headers = curl_slist_append(dav_headers, "Depth: 0");
1042         dav_headers = curl_slist_append(dav_headers, "Content-Type: text/xml");
1043
1044         slot = get_active_slot();
1045         curl_easy_setopt(slot->curl, CURLOPT_INFILE, &out_buffer);
1046         curl_easy_setopt(slot->curl, CURLOPT_INFILESIZE, out_buffer.size);
1047         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, fread_buffer);
1048         curl_easy_setopt(slot->curl, CURLOPT_FILE, &in_buffer);
1049         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
1050         curl_easy_setopt(slot->curl, CURLOPT_URL, remote->url);
1051         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 1);
1052         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, DAV_PROPFIND);
1053         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, dav_headers);
1054
1055         if (start_active_slot(slot)) {
1056                 run_active_slot(slot);
1057                 if (slot->curl_result == CURLE_OK) {
1058                         ctx.name = xcalloc(10, 1);
1059                         ctx.len = 0;
1060                         ctx.cdata = NULL;
1061                         ctx.userFunc = handle_lockprop_ctx;
1062                         ctx.userData = &lock_flags;
1063                         XML_SetUserData(parser, &ctx);
1064                         XML_SetElementHandler(parser, xml_start_tag,
1065                                               xml_end_tag);
1066                         result = XML_Parse(parser, in_buffer.buffer,
1067                                            in_buffer.posn, 1);
1068                         free(ctx.name);
1069
1070                         if (result != XML_STATUS_OK) {
1071                                 fprintf(stderr, "XML error: %s\n",
1072                                         XML_ErrorString(
1073                                                 XML_GetErrorCode(parser)));
1074                                 lock_flags = 0;
1075                         }
1076                 }
1077         } else {
1078                 fprintf(stderr, "Unable to start request\n");
1079         }
1080
1081         free(out_data);
1082         free(in_buffer.buffer);
1083         curl_slist_free_all(dav_headers);
1084
1085         return lock_flags;
1086 }
1087
1088 static int is_ancestor(unsigned char *sha1, struct commit *commit)
1089 {
1090         struct commit_list *parents;
1091
1092         if (parse_commit(commit))
1093                 return 0;
1094         parents = commit->parents;
1095         for (; parents; parents = parents->next) {
1096                 if (!memcmp(sha1, parents->item->object.sha1, 20)) {
1097                         return 1;
1098                 } else if (parents->item->object.type == commit_type) {
1099                         if (is_ancestor(
1100                                     sha1,
1101                                     (struct commit *)&parents->item->object
1102                                     ))
1103                                 return 1;
1104                 }
1105         }
1106         return 0;
1107 }
1108
1109 static void get_delta(unsigned char *sha1, struct object *obj,
1110                       struct active_lock *lock)
1111 {
1112         struct commit *commit;
1113         struct commit_list *parents;
1114         struct tree *tree;
1115         struct tree_entry_list *entry;
1116
1117         if (sha1 && !memcmp(sha1, obj->sha1, 20))
1118                 return;
1119
1120         if (aborted)
1121                 return;
1122
1123         if (obj->type == commit_type) {
1124                 if (push_verbosely)
1125                         fprintf(stderr, "walk %s\n", sha1_to_hex(obj->sha1));
1126                 add_request(obj->sha1, lock);
1127                 commit = (struct commit *)obj;
1128                 if (parse_commit(commit)) {
1129                         fprintf(stderr, "Error parsing commit %s\n",
1130                                 sha1_to_hex(obj->sha1));
1131                         aborted = 1;
1132                         return;
1133                 }
1134                 parents = commit->parents;
1135                 for (; parents; parents = parents->next)
1136                         if (sha1 == NULL ||
1137                             memcmp(sha1, parents->item->object.sha1, 20))
1138                                 get_delta(sha1, &parents->item->object,
1139                                           lock);
1140                 get_delta(sha1, &commit->tree->object, lock);
1141         } else if (obj->type == tree_type) {
1142                 if (push_verbosely)
1143                         fprintf(stderr, "walk %s\n", sha1_to_hex(obj->sha1));
1144                 add_request(obj->sha1, lock);
1145                 tree = (struct tree *)obj;
1146                 if (parse_tree(tree)) {
1147                         fprintf(stderr, "Error parsing tree %s\n",
1148                                 sha1_to_hex(obj->sha1));
1149                         aborted = 1;
1150                         return;
1151                 }
1152                 entry = tree->entries;
1153                 tree->entries = NULL;
1154                 while (entry) {
1155                         struct tree_entry_list *next = entry->next;
1156                         get_delta(sha1, entry->item.any, lock);
1157                         free(entry->name);
1158                         free(entry);
1159                         entry = next;
1160                 }
1161         } else if (obj->type == blob_type || obj->type == tag_type) {
1162                 add_request(obj->sha1, lock);
1163         }
1164 }
1165
1166 static int update_remote(unsigned char *sha1, struct active_lock *lock)
1167 {
1168         struct active_request_slot *slot;
1169         char *out_data;
1170         char *if_header;
1171         struct buffer out_buffer;
1172         struct curl_slist *dav_headers = NULL;
1173         int i;
1174
1175         if_header = xmalloc(strlen(lock->token) + 25);
1176         sprintf(if_header, "If: (<opaquelocktoken:%s>)", lock->token);
1177         dav_headers = curl_slist_append(dav_headers, if_header);
1178
1179         out_buffer.size = 41;
1180         out_data = xmalloc(out_buffer.size + 1);
1181         i = snprintf(out_data, out_buffer.size + 1, "%s\n", sha1_to_hex(sha1));
1182         if (i != out_buffer.size) {
1183                 fprintf(stderr, "Unable to initialize PUT request body\n");
1184                 return 0;
1185         }
1186         out_buffer.posn = 0;
1187         out_buffer.buffer = out_data;
1188
1189         slot = get_active_slot();
1190         curl_easy_setopt(slot->curl, CURLOPT_INFILE, &out_buffer);
1191         curl_easy_setopt(slot->curl, CURLOPT_INFILESIZE, out_buffer.size);
1192         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, fread_buffer);
1193         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_null);
1194         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, DAV_PUT);
1195         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, dav_headers);
1196         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 1);
1197         curl_easy_setopt(slot->curl, CURLOPT_PUT, 1);
1198         curl_easy_setopt(slot->curl, CURLOPT_URL, lock->url);
1199
1200         if (start_active_slot(slot)) {
1201                 run_active_slot(slot);
1202                 free(out_data);
1203                 free(if_header);
1204                 if (slot->curl_result != CURLE_OK) {
1205                         fprintf(stderr,
1206                                 "PUT error: curl result=%d, HTTP code=%ld\n",
1207                                 slot->curl_result, slot->http_code);
1208                         /* We should attempt recovery? */
1209                         return 0;
1210                 }
1211         } else {
1212                 free(out_data);
1213                 free(if_header);
1214                 fprintf(stderr, "Unable to start PUT request\n");
1215                 return 0;
1216         }
1217
1218         return 1;
1219 }
1220
1221 int main(int argc, char **argv)
1222 {
1223         struct transfer_request *request;
1224         struct transfer_request *next_request;
1225         int nr_refspec = 0;
1226         char **refspec = NULL;
1227         int do_remote_update;
1228         int new_branch;
1229         int force_this;
1230         char *local_ref;
1231         unsigned char local_sha1[20];
1232         struct object *local_object = NULL;
1233         char *remote_ref = NULL;
1234         unsigned char remote_sha1[20];
1235         struct active_lock *remote_lock;
1236         char *remote_path = NULL;
1237         int rc = 0;
1238         int i;
1239
1240         setup_git_directory();
1241         setup_ident();
1242
1243         remote = xmalloc(sizeof(*remote));
1244         remote->url = NULL;
1245         remote->packs = NULL;
1246
1247         argv++;
1248         for (i = 1; i < argc; i++, argv++) {
1249                 char *arg = *argv;
1250
1251                 if (*arg == '-') {
1252                         if (!strcmp(arg, "--complete")) {
1253                                 push_all = 1;
1254                                 continue;
1255                         }
1256                         if (!strcmp(arg, "--force")) {
1257                                 force_all = 1;
1258                                 continue;
1259                         }
1260                         if (!strcmp(arg, "--verbose")) {
1261                                 push_verbosely = 1;
1262                                 continue;
1263                         }
1264                         usage(http_push_usage);
1265                 }
1266                 if (!remote->url) {
1267                         remote->url = arg;
1268                         continue;
1269                 }
1270                 refspec = argv;
1271                 nr_refspec = argc - i;
1272                 break;
1273         }
1274
1275         if (!remote->url)
1276                 usage(http_push_usage);
1277
1278         memset(remote_dir_exists, 0, 256);
1279
1280         http_init();
1281
1282         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
1283         default_headers = curl_slist_append(default_headers, "Range:");
1284         default_headers = curl_slist_append(default_headers, "Destination:");
1285         default_headers = curl_slist_append(default_headers, "If:");
1286         default_headers = curl_slist_append(default_headers,
1287                                             "Pragma: no-cache");
1288
1289         /* Verify DAV compliance/lock support */
1290         if (!locking_available()) {
1291                 fprintf(stderr, "Error: no DAV locking support on remote repo %s\n", remote->url);
1292                 rc = 1;
1293                 goto cleanup;
1294         }
1295
1296         /* Process each refspec */
1297         for (i = 0; i < nr_refspec; i++) {
1298                 char *ep;
1299                 force_this = 0;
1300                 do_remote_update = 0;
1301                 new_branch = 0;
1302                 local_ref = refspec[i];
1303                 if (*local_ref == '+') {
1304                         force_this = 1;
1305                         local_ref++;
1306                 }
1307                 ep = strchr(local_ref, ':');
1308                 if (ep) {
1309                         remote_ref = ep + 1;
1310                         *ep = 0;
1311                 }
1312                 else
1313                         remote_ref = local_ref;
1314
1315                 /* Lock remote branch ref */
1316                 if (remote_path)
1317                         free(remote_path);
1318                 remote_path = xmalloc(strlen(remote_ref) + 12);
1319                 sprintf(remote_path, "refs/heads/%s", remote_ref);
1320                 remote_lock = lock_remote(remote_path, LOCK_TIME);
1321                 if (remote_lock == NULL) {
1322                         fprintf(stderr, "Unable to lock remote branch %s\n",
1323                                 remote_ref);
1324                         rc = 1;
1325                         continue;
1326                 }
1327
1328                 /* Resolve local and remote refs */
1329                 if (fetch_ref(remote_ref, remote_sha1) != 0) {
1330                         fprintf(stderr,
1331                                 "Remote branch %s does not exist on %s\n",
1332                                 remote_ref, remote->url);
1333                         new_branch = 1;
1334                 }
1335                 if (get_sha1(local_ref, local_sha1) != 0) {
1336                         fprintf(stderr, "Error resolving local branch %s\n",
1337                                 local_ref);
1338                         rc = 1;
1339                         goto unlock;
1340                 }
1341
1342                 /* Find relationship between local and remote */
1343                 local_object = parse_object(local_sha1);
1344                 if (!local_object) {
1345                         fprintf(stderr, "Unable to parse local object %s\n",
1346                                 sha1_to_hex(local_sha1));
1347                         rc = 1;
1348                         goto unlock;
1349                 } else if (new_branch) {
1350                         do_remote_update = 1;
1351                 } else {
1352                         if (!memcmp(local_sha1, remote_sha1, 20)) {
1353                                 fprintf(stderr,
1354                                         "* %s: same as branch '%s' of %s\n",
1355                                         local_ref, remote_ref, remote->url);
1356                         } else if (is_ancestor(remote_sha1,
1357                                                (struct commit *)local_object)) {
1358                                 fprintf(stderr,
1359                                         "Remote %s will fast-forward to local %s\n",
1360                                         remote_ref, local_ref);
1361                                 do_remote_update = 1;
1362                         } else if (force_all || force_this) {
1363                                 fprintf(stderr,
1364                                         "* %s on %s does not fast forward to local branch '%s', overwriting\n",
1365                                         remote_ref, remote->url, local_ref);
1366                                 do_remote_update = 1;
1367                         } else {
1368                                 fprintf(stderr,
1369                                         "* %s on %s does not fast forward to local branch '%s'\n",
1370                                         remote_ref, remote->url, local_ref);
1371                                 rc = 1;
1372                                 goto unlock;
1373                         }
1374                 }
1375
1376                 /* Generate and check list of required objects */
1377                 pushing = 0;
1378                 if (do_remote_update || push_all)
1379                         fetch_indices();
1380                 get_delta(push_all ? NULL : remote_sha1,
1381                           local_object, remote_lock);
1382                 finish_all_active_slots();
1383
1384                 /* Push missing objects to remote, this would be a
1385                    convenient time to pack them first if appropriate. */
1386                 pushing = 1;
1387                 fill_active_slots();
1388                 finish_all_active_slots();
1389
1390                 /* Update the remote branch if all went well */
1391                 if (do_remote_update) {
1392                         if (!aborted && update_remote(local_sha1,
1393                                                       remote_lock)) {
1394                                 fprintf(stderr, "%s remote branch %s\n",
1395                                         new_branch ? "Created" : "Updated",
1396                                         remote_ref);
1397                         } else {
1398                                 fprintf(stderr,
1399                                         "Unable to %s remote branch %s\n",
1400                                         new_branch ? "create" : "update",
1401                                         remote_ref);
1402                                 rc = 1;
1403                                 goto unlock;
1404                         }
1405                 }
1406
1407         unlock:
1408                 unlock_remote(remote_lock);
1409                 free(remote_path);
1410         }
1411
1412  cleanup:
1413         free(remote);
1414
1415         curl_slist_free_all(no_pragma_header);
1416         curl_slist_free_all(default_headers);
1417
1418         http_cleanup();
1419
1420         request = request_queue_head;
1421         while (request != NULL) {
1422                 next_request = request->next;
1423                 release_request(request);
1424                 request = next_request;
1425         }
1426
1427         return rc;
1428 }