Andrew's git / gitweb.git / connect.c
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connect.con commit Everyday: some examples. (44db136)
   1#include "cache.h"
   2#include "pkt-line.h"
   3#include "quote.h"
   4#include "refs.h"
   5#include <sys/wait.h>
   6#include <sys/socket.h>
   7#include <netinet/in.h>
   8#include <arpa/inet.h>
   9#include <netdb.h>
  10
  11static char *server_capabilities = NULL;
  12
  13/*
  14 * Read all the refs from the other end
  15 */
  16struct ref **get_remote_heads(int in, struct ref **list,
  17                              int nr_match, char **match, int ignore_funny)
  18{
  19        *list = NULL;
  20        for (;;) {
  21                struct ref *ref;
  22                unsigned char old_sha1[20];
  23                static char buffer[1000];
  24                char *name;
  25                int len, name_len;
  26
  27                len = packet_read_line(in, buffer, sizeof(buffer));
  28                if (!len)
  29                        break;
  30                if (buffer[len-1] == '\n')
  31                        buffer[--len] = 0;
  32
  33                if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
  34                        die("protocol error: expected sha/ref, got '%s'", buffer);
  35                name = buffer + 41;
  36
  37                if (ignore_funny && 45 < len && !memcmp(name, "refs/", 5) &&
  38                    check_ref_format(name + 5))
  39                        continue;
  40
  41                name_len = strlen(name);
  42                if (len != name_len + 41) {
  43                        if (server_capabilities)
  44                                free(server_capabilities);
  45                        server_capabilities = strdup(name + name_len + 1);
  46                }
  47
  48                if (nr_match && !path_match(name, nr_match, match))
  49                        continue;
  50                ref = xcalloc(1, sizeof(*ref) + len - 40);
  51                memcpy(ref->old_sha1, old_sha1, 20);
  52                memcpy(ref->name, buffer + 41, len - 40);
  53                *list = ref;
  54                list = &ref->next;
  55        }
  56        return list;
  57}
  58
  59int server_supports(const char *feature)
  60{
  61        return server_capabilities &&
  62                strstr(server_capabilities, feature) != NULL;
  63}
  64
  65int get_ack(int fd, unsigned char *result_sha1)
  66{
  67        static char line[1000];
  68        int len = packet_read_line(fd, line, sizeof(line));
  69
  70        if (!len)
  71                die("git-fetch-pack: expected ACK/NAK, got EOF");
  72        if (line[len-1] == '\n')
  73                line[--len] = 0;
  74        if (!strcmp(line, "NAK"))
  75                return 0;
  76        if (!strncmp(line, "ACK ", 3)) {
  77                if (!get_sha1_hex(line+4, result_sha1)) {
  78                        if (strstr(line+45, "continue"))
  79                                return 2;
  80                        return 1;
  81                }
  82        }
  83        die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
  84}
  85
  86int path_match(const char *path, int nr, char **match)
  87{
  88        int i;
  89        int pathlen = strlen(path);
  90
  91        for (i = 0; i < nr; i++) {
  92                char *s = match[i];
  93                int len = strlen(s);
  94
  95                if (!len || len > pathlen)
  96                        continue;
  97                if (memcmp(path + pathlen - len, s, len))
  98                        continue;
  99                if (pathlen > len && path[pathlen - len - 1] != '/')
 100                        continue;
 101                *s = 0;
 102                return 1;
 103        }
 104        return 0;
 105}
 106
 107struct refspec {
 108        char *src;
 109        char *dst;
 110        char force;
 111};
 112
 113/*
 114 * A:B means fast forward remote B with local A.
 115 * +A:B means overwrite remote B with local A.
 116 * +A is a shorthand for +A:A.
 117 * A is a shorthand for A:A.
 118 */
 119static struct refspec *parse_ref_spec(int nr_refspec, char **refspec)
 120{
 121        int i;
 122        struct refspec *rs = xcalloc(sizeof(*rs), (nr_refspec + 1));
 123        for (i = 0; i < nr_refspec; i++) {
 124                char *sp, *dp, *ep;
 125                sp = refspec[i];
 126                if (*sp == '+') {
 127                        rs[i].force = 1;
 128                        sp++;
 129                }
 130                ep = strchr(sp, ':');
 131                if (ep) {
 132                        dp = ep + 1;
 133                        *ep = 0;
 134                }
 135                else
 136                        dp = sp;
 137                rs[i].src = sp;
 138                rs[i].dst = dp;
 139        }
 140        rs[nr_refspec].src = rs[nr_refspec].dst = NULL;
 141        return rs;
 142}
 143
 144static int count_refspec_match(const char *pattern,
 145                               struct ref *refs,
 146                               struct ref **matched_ref)
 147{
 148        int match;
 149        int patlen = strlen(pattern);
 150
 151        for (match = 0; refs; refs = refs->next) {
 152                char *name = refs->name;
 153                int namelen = strlen(name);
 154                if (namelen < patlen ||
 155                    memcmp(name + namelen - patlen, pattern, patlen))
 156                        continue;
 157                if (namelen != patlen && name[namelen - patlen - 1] != '/')
 158                        continue;
 159                match++;
 160                *matched_ref = refs;
 161        }
 162        return match;
 163}
 164
 165static void link_dst_tail(struct ref *ref, struct ref ***tail)
 166{
 167        **tail = ref;
 168        *tail = &ref->next;
 169        **tail = NULL;
 170}
 171
 172static struct ref *try_explicit_object_name(const char *name)
 173{
 174        unsigned char sha1[20];
 175        struct ref *ref;
 176        int len;
 177        if (get_sha1(name, sha1))
 178                return NULL;
 179        len = strlen(name) + 1;
 180        ref = xcalloc(1, sizeof(*ref) + len);
 181        memcpy(ref->name, name, len);
 182        memcpy(ref->new_sha1, sha1, 20);
 183        return ref;
 184}
 185
 186static int match_explicit_refs(struct ref *src, struct ref *dst,
 187                               struct ref ***dst_tail, struct refspec *rs)
 188{
 189        int i, errs;
 190        for (i = errs = 0; rs[i].src; i++) {
 191                struct ref *matched_src, *matched_dst;
 192
 193                matched_src = matched_dst = NULL;
 194                switch (count_refspec_match(rs[i].src, src, &matched_src)) {
 195                case 1:
 196                        break;
 197                case 0:
 198                        /* The source could be in the get_sha1() format
 199                         * not a reference name.
 200                         */
 201                        matched_src = try_explicit_object_name(rs[i].src);
 202                        if (matched_src)
 203                                break;
 204                        errs = 1;
 205                        error("src refspec %s does not match any.",
 206                              rs[i].src);
 207                        break;
 208                default:
 209                        errs = 1;
 210                        error("src refspec %s matches more than one.",
 211                              rs[i].src);
 212                        break;
 213                }
 214                switch (count_refspec_match(rs[i].dst, dst, &matched_dst)) {
 215                case 1:
 216                        break;
 217                case 0:
 218                        if (!memcmp(rs[i].dst, "refs/", 5)) {
 219                                int len = strlen(rs[i].dst) + 1;
 220                                matched_dst = xcalloc(1, sizeof(*dst) + len);
 221                                memcpy(matched_dst->name, rs[i].dst, len);
 222                                link_dst_tail(matched_dst, dst_tail);
 223                        }
 224                        else if (!strcmp(rs[i].src, rs[i].dst) &&
 225                                 matched_src) {
 226                                /* pushing "master:master" when
 227                                 * remote does not have master yet.
 228                                 */
 229                                int len = strlen(matched_src->name) + 1;
 230                                matched_dst = xcalloc(1, sizeof(*dst) + len);
 231                                memcpy(matched_dst->name, matched_src->name,
 232                                       len);
 233                                link_dst_tail(matched_dst, dst_tail);
 234                        }
 235                        else {
 236                                errs = 1;
 237                                error("dst refspec %s does not match any "
 238                                      "existing ref on the remote and does "
 239                                      "not start with refs/.", rs[i].dst);
 240                        }
 241                        break;
 242                default:
 243                        errs = 1;
 244                        error("dst refspec %s matches more than one.",
 245                              rs[i].dst);
 246                        break;
 247                }
 248                if (errs)
 249                        continue;
 250                if (matched_dst->peer_ref) {
 251                        errs = 1;
 252                        error("dst ref %s receives from more than one src.",
 253                              matched_dst->name);
 254                }
 255                else {
 256                        matched_dst->peer_ref = matched_src;
 257                        matched_dst->force = rs[i].force;
 258                }
 259        }
 260        return -errs;
 261}
 262
 263static struct ref *find_ref_by_name(struct ref *list, const char *name)
 264{
 265        for ( ; list; list = list->next)
 266                if (!strcmp(list->name, name))
 267                        return list;
 268        return NULL;
 269}
 270
 271int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 272               int nr_refspec, char **refspec, int all)
 273{
 274        struct refspec *rs = parse_ref_spec(nr_refspec, refspec);
 275
 276        if (nr_refspec)
 277                return match_explicit_refs(src, dst, dst_tail, rs);
 278
 279        /* pick the remainder */
 280        for ( ; src; src = src->next) {
 281                struct ref *dst_peer;
 282                if (src->peer_ref)
 283                        continue;
 284                dst_peer = find_ref_by_name(dst, src->name);
 285                if ((dst_peer && dst_peer->peer_ref) || (!dst_peer && !all))
 286                        continue;
 287                if (!dst_peer) {
 288                        /* Create a new one and link it */
 289                        int len = strlen(src->name) + 1;
 290                        dst_peer = xcalloc(1, sizeof(*dst_peer) + len);
 291                        memcpy(dst_peer->name, src->name, len);
 292                        memcpy(dst_peer->new_sha1, src->new_sha1, 20);
 293                        link_dst_tail(dst_peer, dst_tail);
 294                }
 295                dst_peer->peer_ref = src;
 296        }
 297        return 0;
 298}
 299
 300enum protocol {
 301        PROTO_LOCAL = 1,
 302        PROTO_SSH,
 303        PROTO_GIT,
 304};
 305
 306static enum protocol get_protocol(const char *name)
 307{
 308        if (!strcmp(name, "ssh"))
 309                return PROTO_SSH;
 310        if (!strcmp(name, "git"))
 311                return PROTO_GIT;
 312        if (!strcmp(name, "git+ssh"))
 313                return PROTO_SSH;
 314        if (!strcmp(name, "ssh+git"))
 315                return PROTO_SSH;
 316        die("I don't handle protocol '%s'", name);
 317}
 318
 319#define STR_(s) # s
 320#define STR(s)  STR_(s)
 321
 322#ifndef NO_IPV6
 323
 324static int git_tcp_connect(int fd[2], const char *prog, char *host, char *path)
 325{
 326        int sockfd = -1;
 327        char *colon, *end;
 328        char *port = STR(DEFAULT_GIT_PORT);
 329        struct addrinfo hints, *ai0, *ai;
 330        int gai;
 331
 332        if (host[0] == '[') {
 333                end = strchr(host + 1, ']');
 334                if (end) {
 335                        *end = 0;
 336                        end++;
 337                        host++;
 338                } else
 339                        end = host;
 340        } else
 341                end = host;
 342        colon = strchr(end, ':');
 343
 344        if (colon) {
 345                *colon = 0;
 346                port = colon + 1;
 347        }
 348
 349        memset(&hints, 0, sizeof(hints));
 350        hints.ai_socktype = SOCK_STREAM;
 351        hints.ai_protocol = IPPROTO_TCP;
 352
 353        gai = getaddrinfo(host, port, &hints, &ai);
 354        if (gai)
 355                die("Unable to look up %s (%s)", host, gai_strerror(gai));
 356
 357        for (ai0 = ai; ai; ai = ai->ai_next) {
 358                sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 359                if (sockfd < 0)
 360                        continue;
 361                if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
 362                        close(sockfd);
 363                        sockfd = -1;
 364                        continue;
 365                }
 366                break;
 367        }
 368
 369        freeaddrinfo(ai0);
 370
 371        if (sockfd < 0)
 372                die("unable to connect a socket (%s)", strerror(errno));
 373
 374        fd[0] = sockfd;
 375        fd[1] = sockfd;
 376        packet_write(sockfd, "%s %s\n", prog, path);
 377        return 0;
 378}
 379
 380#else /* NO_IPV6 */
 381
 382static int git_tcp_connect(int fd[2], const char *prog, char *host, char *path)
 383{
 384        int sockfd = -1;
 385        char *colon, *end;
 386        char *port = STR(DEFAULT_GIT_PORT), *ep;
 387        struct hostent *he;
 388        struct sockaddr_in sa;
 389        char **ap;
 390        unsigned int nport;
 391
 392        if (host[0] == '[') {
 393                end = strchr(host + 1, ']');
 394                if (end) {
 395                        *end = 0;
 396                        end++;
 397                        host++;
 398                } else
 399                        end = host;
 400        } else
 401                end = host;
 402        colon = strchr(end, ':');
 403
 404        if (colon) {
 405                *colon = 0;
 406                port = colon + 1;
 407        }
 408
 409
 410        he = gethostbyname(host);
 411        if (!he)
 412                die("Unable to look up %s (%s)", host, hstrerror(h_errno));
 413        nport = strtoul(port, &ep, 10);
 414        if ( ep == port || *ep ) {
 415                /* Not numeric */
 416                struct servent *se = getservbyname(port,"tcp");
 417                if ( !se )
 418                        die("Unknown port %s\n", port);
 419                nport = se->s_port;
 420        }
 421
 422        for (ap = he->h_addr_list; *ap; ap++) {
 423                sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
 424                if (sockfd < 0)
 425                        continue;
 426
 427                memset(&sa, 0, sizeof sa);
 428                sa.sin_family = he->h_addrtype;
 429                sa.sin_port = htons(nport);
 430                memcpy(&sa.sin_addr, *ap, he->h_length);
 431
 432                if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
 433                        close(sockfd);
 434                        sockfd = -1;
 435                        continue;
 436                }
 437                break;
 438        }
 439
 440        if (sockfd < 0)
 441                die("unable to connect a socket (%s)", strerror(errno));
 442
 443        fd[0] = sockfd;
 444        fd[1] = sockfd;
 445        packet_write(sockfd, "%s %s\n", prog, path);
 446        return 0;
 447}
 448
 449#endif /* NO_IPV6 */
 450
 451static char *git_proxy_command = NULL;
 452static const char *rhost_name = NULL;
 453static int rhost_len;
 454
 455static int git_proxy_command_options(const char *var, const char *value)
 456{
 457        if (!strcmp(var, "core.gitproxy")) {
 458                const char *for_pos;
 459                int matchlen = -1;
 460                int hostlen;
 461
 462                if (git_proxy_command)
 463                        return 0;
 464                /* [core]
 465                 * ;# matches www.kernel.org as well
 466                 * gitproxy = netcatter-1 for kernel.org
 467                 * gitproxy = netcatter-2 for sample.xz
 468                 * gitproxy = netcatter-default
 469                 */
 470                for_pos = strstr(value, " for ");
 471                if (!for_pos)
 472                        /* matches everybody */
 473                        matchlen = strlen(value);
 474                else {
 475                        hostlen = strlen(for_pos + 5);
 476                        if (rhost_len < hostlen)
 477                                matchlen = -1;
 478                        else if (!strncmp(for_pos + 5,
 479                                          rhost_name + rhost_len - hostlen,
 480                                          hostlen) &&
 481                                 ((rhost_len == hostlen) ||
 482                                  rhost_name[rhost_len - hostlen -1] == '.'))
 483                                matchlen = for_pos - value;
 484                        else
 485                                matchlen = -1;
 486                }
 487                if (0 <= matchlen) {
 488                        /* core.gitproxy = none for kernel.org */
 489                        if (matchlen == 4 && 
 490                            !memcmp(value, "none", 4))
 491                                matchlen = 0;
 492                        git_proxy_command = xmalloc(matchlen + 1);
 493                        memcpy(git_proxy_command, value, matchlen);
 494                        git_proxy_command[matchlen] = 0;
 495                }
 496                return 0;
 497        }
 498
 499        return git_default_config(var, value);
 500}
 501
 502static int git_use_proxy(const char *host)
 503{
 504        rhost_name = host;
 505        rhost_len = strlen(host);
 506        git_proxy_command = getenv("GIT_PROXY_COMMAND");
 507        git_config(git_proxy_command_options);
 508        rhost_name = NULL;
 509        return (git_proxy_command && *git_proxy_command);
 510}
 511
 512static int git_proxy_connect(int fd[2], const char *prog, char *host, char *path)
 513{
 514        char *port = STR(DEFAULT_GIT_PORT);
 515        char *colon, *end;
 516        int pipefd[2][2];
 517        pid_t pid;
 518
 519        if (host[0] == '[') {
 520                end = strchr(host + 1, ']');
 521                if (end) {
 522                        *end = 0;
 523                        end++;
 524                        host++;
 525                } else
 526                        end = host;
 527        } else
 528                end = host;
 529        colon = strchr(end, ':');
 530
 531        if (colon) {
 532                *colon = 0;
 533                port = colon + 1;
 534        }
 535
 536        if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
 537                die("unable to create pipe pair for communication");
 538        pid = fork();
 539        if (!pid) {
 540                dup2(pipefd[1][0], 0);
 541                dup2(pipefd[0][1], 1);
 542                close(pipefd[0][0]);
 543                close(pipefd[0][1]);
 544                close(pipefd[1][0]);
 545                close(pipefd[1][1]);
 546                execlp(git_proxy_command, git_proxy_command, host, port, NULL);
 547                die("exec failed");
 548        }
 549        fd[0] = pipefd[0][0];
 550        fd[1] = pipefd[1][1];
 551        close(pipefd[0][1]);
 552        close(pipefd[1][0]);
 553        packet_write(fd[1], "%s %s\n", prog, path);
 554        return pid;
 555}
 556
 557/*
 558 * Yeah, yeah, fixme. Need to pass in the heads etc.
 559 */
 560int git_connect(int fd[2], char *url, const char *prog)
 561{
 562        char command[1024];
 563        char *host, *path = url;
 564        char *colon = NULL;
 565        int pipefd[2][2];
 566        pid_t pid;
 567        enum protocol protocol = PROTO_LOCAL;
 568
 569        host = strstr(url, "://");
 570        if(host) {
 571                *host = '\0';
 572                protocol = get_protocol(url);
 573                host += 3;
 574                path = strchr(host, '/');
 575        }
 576        else {
 577                host = url;
 578                if ((colon = strchr(host, ':'))) {
 579                        protocol = PROTO_SSH;
 580                        *colon = '\0';
 581                        path = colon + 1;
 582                }
 583        }
 584
 585        if (!path || !*path)
 586                die("No path specified. See 'man git-pull' for valid url syntax");
 587
 588        /*
 589         * null-terminate hostname and point path to ~ for URL's like this:
 590         *    ssh://host.xz/~user/repo
 591         */
 592        if (protocol != PROTO_LOCAL && host != url) {
 593                char *ptr = path;
 594                if (path[1] == '~')
 595                        path++;
 596                else
 597                        path = strdup(ptr);
 598
 599                *ptr = '\0';
 600        }
 601
 602        if (protocol == PROTO_GIT) {
 603                if (git_use_proxy(host))
 604                        return git_proxy_connect(fd, prog, host, path);
 605                return git_tcp_connect(fd, prog, host, path);
 606        }
 607
 608        if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
 609                die("unable to create pipe pair for communication");
 610        pid = fork();
 611        if (!pid) {
 612                snprintf(command, sizeof(command), "%s %s", prog,
 613                         sq_quote(path));
 614                dup2(pipefd[1][0], 0);
 615                dup2(pipefd[0][1], 1);
 616                close(pipefd[0][0]);
 617                close(pipefd[0][1]);
 618                close(pipefd[1][0]);
 619                close(pipefd[1][1]);
 620                if (protocol == PROTO_SSH) {
 621                        const char *ssh, *ssh_basename;
 622                        ssh = getenv("GIT_SSH");
 623                        if (!ssh) ssh = "ssh";
 624                        ssh_basename = strrchr(ssh, '/');
 625                        if (!ssh_basename)
 626                                ssh_basename = ssh;
 627                        else
 628                                ssh_basename++;
 629                        execlp(ssh, ssh_basename, host, command, NULL);
 630                }
 631                else
 632                        execlp("sh", "sh", "-c", command, NULL);
 633                die("exec failed");
 634        }               
 635        fd[0] = pipefd[0][0];
 636        fd[1] = pipefd[1][1];
 637        close(pipefd[0][1]);
 638        close(pipefd[1][0]);
 639        return pid;
 640}
 641
 642int finish_connect(pid_t pid)
 643{
 644        int ret;
 645
 646        for (;;) {
 647                ret = waitpid(pid, NULL, 0);
 648                if (!ret)
 649                        break;
 650                if (errno != EINTR)
 651                        break;
 652        }
 653        return ret;
 654}