Andrew's git / gitweb.git / connect.c
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connect.con commit git-fetch-pack: Implement client part of the multi_ack extension (40a1046)
   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
  11/*
  12 * Read all the refs from the other end
  13 */
  14struct ref **get_remote_heads(int in, struct ref **list,
  15                              int nr_match, char **match, int ignore_funny)
  16{
  17        *list = NULL;
  18        for (;;) {
  19                struct ref *ref;
  20                unsigned char old_sha1[20];
  21                static char buffer[1000];
  22                char *name;
  23                int len;
  24
  25                len = packet_read_line(in, buffer, sizeof(buffer));
  26                if (!len)
  27                        break;
  28                if (buffer[len-1] == '\n')
  29                        buffer[--len] = 0;
  30
  31                if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
  32                        die("protocol error: expected sha/ref, got '%s'", buffer);
  33                name = buffer + 41;
  34
  35                if (ignore_funny && 45 < len && !memcmp(name, "refs/", 5) &&
  36                    check_ref_format(name + 5))
  37                        continue;
  38
  39                if (nr_match && !path_match(name, nr_match, match))
  40                        continue;
  41                ref = xcalloc(1, sizeof(*ref) + len - 40);
  42                memcpy(ref->old_sha1, old_sha1, 20);
  43                memcpy(ref->name, buffer + 41, len - 40);
  44                *list = ref;
  45                list = &ref->next;
  46        }
  47        return list;
  48}
  49
  50int get_ack(int fd, unsigned char *result_sha1)
  51{
  52        static char line[1000];
  53        int len = packet_read_line(fd, line, sizeof(line));
  54
  55        if (!len)
  56                die("git-fetch-pack: expected ACK/NAK, got EOF");
  57        if (line[len-1] == '\n')
  58                line[--len] = 0;
  59        if (!strcmp(line, "NAK"))
  60                return 0;
  61        if (!strncmp(line, "ACK ", 3)) {
  62                if (!get_sha1_hex(line+4, result_sha1)) {
  63                        if (strstr(line+45, "continue"))
  64                                return 2;
  65                        return 1;
  66                }
  67        }
  68        die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
  69}
  70
  71int path_match(const char *path, int nr, char **match)
  72{
  73        int i;
  74        int pathlen = strlen(path);
  75
  76        for (i = 0; i < nr; i++) {
  77                char *s = match[i];
  78                int len = strlen(s);
  79
  80                if (!len || len > pathlen)
  81                        continue;
  82                if (memcmp(path + pathlen - len, s, len))
  83                        continue;
  84                if (pathlen > len && path[pathlen - len - 1] != '/')
  85                        continue;
  86                *s = 0;
  87                return 1;
  88        }
  89        return 0;
  90}
  91
  92struct refspec {
  93        char *src;
  94        char *dst;
  95        char force;
  96};
  97
  98/*
  99 * A:B means fast forward remote B with local A.
 100 * +A:B means overwrite remote B with local A.
 101 * +A is a shorthand for +A:A.
 102 * A is a shorthand for A:A.
 103 */
 104static struct refspec *parse_ref_spec(int nr_refspec, char **refspec)
 105{
 106        int i;
 107        struct refspec *rs = xcalloc(sizeof(*rs), (nr_refspec + 1));
 108        for (i = 0; i < nr_refspec; i++) {
 109                char *sp, *dp, *ep;
 110                sp = refspec[i];
 111                if (*sp == '+') {
 112                        rs[i].force = 1;
 113                        sp++;
 114                }
 115                ep = strchr(sp, ':');
 116                if (ep) {
 117                        dp = ep + 1;
 118                        *ep = 0;
 119                }
 120                else
 121                        dp = sp;
 122                rs[i].src = sp;
 123                rs[i].dst = dp;
 124        }
 125        rs[nr_refspec].src = rs[nr_refspec].dst = NULL;
 126        return rs;
 127}
 128
 129static int count_refspec_match(const char *pattern,
 130                               struct ref *refs,
 131                               struct ref **matched_ref)
 132{
 133        int match;
 134        int patlen = strlen(pattern);
 135
 136        for (match = 0; refs; refs = refs->next) {
 137                char *name = refs->name;
 138                int namelen = strlen(name);
 139                if (namelen < patlen ||
 140                    memcmp(name + namelen - patlen, pattern, patlen))
 141                        continue;
 142                if (namelen != patlen && name[namelen - patlen - 1] != '/')
 143                        continue;
 144                match++;
 145                *matched_ref = refs;
 146        }
 147        return match;
 148}
 149
 150static void link_dst_tail(struct ref *ref, struct ref ***tail)
 151{
 152        **tail = ref;
 153        *tail = &ref->next;
 154        **tail = NULL;
 155}
 156
 157static struct ref *try_explicit_object_name(const char *name)
 158{
 159        unsigned char sha1[20];
 160        struct ref *ref;
 161        int len;
 162        if (get_sha1(name, sha1))
 163                return NULL;
 164        len = strlen(name) + 1;
 165        ref = xcalloc(1, sizeof(*ref) + len);
 166        memcpy(ref->name, name, len);
 167        memcpy(ref->new_sha1, sha1, 20);
 168        return ref;
 169}
 170
 171static int match_explicit_refs(struct ref *src, struct ref *dst,
 172                               struct ref ***dst_tail, struct refspec *rs)
 173{
 174        int i, errs;
 175        for (i = errs = 0; rs[i].src; i++) {
 176                struct ref *matched_src, *matched_dst;
 177
 178                matched_src = matched_dst = NULL;
 179                switch (count_refspec_match(rs[i].src, src, &matched_src)) {
 180                case 1:
 181                        break;
 182                case 0:
 183                        /* The source could be in the get_sha1() format
 184                         * not a reference name.
 185                         */
 186                        matched_src = try_explicit_object_name(rs[i].src);
 187                        if (matched_src)
 188                                break;
 189                        errs = 1;
 190                        error("src refspec %s does not match any.",
 191                              rs[i].src);
 192                        break;
 193                default:
 194                        errs = 1;
 195                        error("src refspec %s matches more than one.",
 196                              rs[i].src);
 197                        break;
 198                }
 199                switch (count_refspec_match(rs[i].dst, dst, &matched_dst)) {
 200                case 1:
 201                        break;
 202                case 0:
 203                        if (!memcmp(rs[i].dst, "refs/", 5)) {
 204                                int len = strlen(rs[i].dst) + 1;
 205                                matched_dst = xcalloc(1, sizeof(*dst) + len);
 206                                memcpy(matched_dst->name, rs[i].dst, len);
 207                                link_dst_tail(matched_dst, dst_tail);
 208                        }
 209                        else if (!strcmp(rs[i].src, rs[i].dst) &&
 210                                 matched_src) {
 211                                /* pushing "master:master" when
 212                                 * remote does not have master yet.
 213                                 */
 214                                int len = strlen(matched_src->name) + 1;
 215                                matched_dst = xcalloc(1, sizeof(*dst) + len);
 216                                memcpy(matched_dst->name, matched_src->name,
 217                                       len);
 218                                link_dst_tail(matched_dst, dst_tail);
 219                        }
 220                        else {
 221                                errs = 1;
 222                                error("dst refspec %s does not match any "
 223                                      "existing ref on the remote and does "
 224                                      "not start with refs/.", rs[i].dst);
 225                        }
 226                        break;
 227                default:
 228                        errs = 1;
 229                        error("dst refspec %s matches more than one.",
 230                              rs[i].dst);
 231                        break;
 232                }
 233                if (errs)
 234                        continue;
 235                if (matched_dst->peer_ref) {
 236                        errs = 1;
 237                        error("dst ref %s receives from more than one src.",
 238                              matched_dst->name);
 239                }
 240                else {
 241                        matched_dst->peer_ref = matched_src;
 242                        matched_dst->force = rs[i].force;
 243                }
 244        }
 245        return -errs;
 246}
 247
 248static struct ref *find_ref_by_name(struct ref *list, const char *name)
 249{
 250        for ( ; list; list = list->next)
 251                if (!strcmp(list->name, name))
 252                        return list;
 253        return NULL;
 254}
 255
 256int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 257               int nr_refspec, char **refspec, int all)
 258{
 259        struct refspec *rs = parse_ref_spec(nr_refspec, refspec);
 260
 261        if (nr_refspec)
 262                return match_explicit_refs(src, dst, dst_tail, rs);
 263
 264        /* pick the remainder */
 265        for ( ; src; src = src->next) {
 266                struct ref *dst_peer;
 267                if (src->peer_ref)
 268                        continue;
 269                dst_peer = find_ref_by_name(dst, src->name);
 270                if ((dst_peer && dst_peer->peer_ref) || (!dst_peer && !all))
 271                        continue;
 272                if (!dst_peer) {
 273                        /* Create a new one and link it */
 274                        int len = strlen(src->name) + 1;
 275                        dst_peer = xcalloc(1, sizeof(*dst_peer) + len);
 276                        memcpy(dst_peer->name, src->name, len);
 277                        memcpy(dst_peer->new_sha1, src->new_sha1, 20);
 278                        link_dst_tail(dst_peer, dst_tail);
 279                }
 280                dst_peer->peer_ref = src;
 281        }
 282        return 0;
 283}
 284
 285enum protocol {
 286        PROTO_LOCAL = 1,
 287        PROTO_SSH,
 288        PROTO_GIT,
 289};
 290
 291static enum protocol get_protocol(const char *name)
 292{
 293        if (!strcmp(name, "ssh"))
 294                return PROTO_SSH;
 295        if (!strcmp(name, "git"))
 296                return PROTO_GIT;
 297        if (!strcmp(name, "git+ssh"))
 298                return PROTO_SSH;
 299        if (!strcmp(name, "ssh+git"))
 300                return PROTO_SSH;
 301        die("I don't handle protocol '%s'", name);
 302}
 303
 304#define STR_(s) # s
 305#define STR(s)  STR_(s)
 306
 307#ifndef NO_IPV6
 308
 309static int git_tcp_connect(int fd[2], const char *prog, char *host, char *path)
 310{
 311        int sockfd = -1;
 312        char *colon, *end;
 313        char *port = STR(DEFAULT_GIT_PORT);
 314        struct addrinfo hints, *ai0, *ai;
 315        int gai;
 316
 317        if (host[0] == '[') {
 318                end = strchr(host + 1, ']');
 319                if (end) {
 320                        *end = 0;
 321                        end++;
 322                        host++;
 323                } else
 324                        end = host;
 325        } else
 326                end = host;
 327        colon = strchr(end, ':');
 328
 329        if (colon) {
 330                *colon = 0;
 331                port = colon + 1;
 332        }
 333
 334        memset(&hints, 0, sizeof(hints));
 335        hints.ai_socktype = SOCK_STREAM;
 336        hints.ai_protocol = IPPROTO_TCP;
 337
 338        gai = getaddrinfo(host, port, &hints, &ai);
 339        if (gai)
 340                die("Unable to look up %s (%s)", host, gai_strerror(gai));
 341
 342        for (ai0 = ai; ai; ai = ai->ai_next) {
 343                sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 344                if (sockfd < 0)
 345                        continue;
 346                if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
 347                        close(sockfd);
 348                        sockfd = -1;
 349                        continue;
 350                }
 351                break;
 352        }
 353
 354        freeaddrinfo(ai0);
 355
 356        if (sockfd < 0)
 357                die("unable to connect a socket (%s)", strerror(errno));
 358
 359        fd[0] = sockfd;
 360        fd[1] = sockfd;
 361        packet_write(sockfd, "%s %s\n", prog, path);
 362        return 0;
 363}
 364
 365#else /* NO_IPV6 */
 366
 367static int git_tcp_connect(int fd[2], const char *prog, char *host, char *path)
 368{
 369        int sockfd = -1;
 370        char *colon, *end;
 371        char *port = STR(DEFAULT_GIT_PORT), *ep;
 372        struct hostent *he;
 373        struct sockaddr_in sa;
 374        char **ap;
 375        unsigned int nport;
 376
 377        if (host[0] == '[') {
 378                end = strchr(host + 1, ']');
 379                if (end) {
 380                        *end = 0;
 381                        end++;
 382                        host++;
 383                } else
 384                        end = host;
 385        } else
 386                end = host;
 387        colon = strchr(end, ':');
 388
 389        if (colon) {
 390                *colon = 0;
 391                port = colon + 1;
 392        }
 393
 394
 395        he = gethostbyname(host);
 396        if (!he)
 397                die("Unable to look up %s (%s)", host, hstrerror(h_errno));
 398        nport = strtoul(port, &ep, 10);
 399        if ( ep == port || *ep ) {
 400                /* Not numeric */
 401                struct servent *se = getservbyname(port,"tcp");
 402                if ( !se )
 403                        die("Unknown port %s\n", port);
 404                nport = se->s_port;
 405        }
 406
 407        for (ap = he->h_addr_list; *ap; ap++) {
 408                sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
 409                if (sockfd < 0)
 410                        continue;
 411
 412                memset(&sa, 0, sizeof sa);
 413                sa.sin_family = he->h_addrtype;
 414                sa.sin_port = htons(nport);
 415                memcpy(&sa.sin_addr, ap, he->h_length);
 416
 417                if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
 418                        close(sockfd);
 419                        sockfd = -1;
 420                        continue;
 421                }
 422                break;
 423        }
 424
 425        if (sockfd < 0)
 426                die("unable to connect a socket (%s)", strerror(errno));
 427
 428        fd[0] = sockfd;
 429        fd[1] = sockfd;
 430        packet_write(sockfd, "%s %s\n", prog, path);
 431        return 0;
 432}
 433
 434#endif /* NO_IPV6 */
 435
 436/*
 437 * Yeah, yeah, fixme. Need to pass in the heads etc.
 438 */
 439int git_connect(int fd[2], char *url, const char *prog)
 440{
 441        char command[1024];
 442        char *host, *path;
 443        char *colon;
 444        int pipefd[2][2];
 445        pid_t pid;
 446        enum protocol protocol;
 447
 448        host = NULL;
 449        path = url;
 450        colon = strchr(url, ':');
 451        protocol = PROTO_LOCAL;
 452        if (colon) {
 453                *colon = 0;
 454                host = url;
 455                path = colon+1;
 456                protocol = PROTO_SSH;
 457                if (!memcmp(path, "//", 2)) {
 458                        char *slash = strchr(path + 2, '/');
 459                        if (slash) {
 460                                int nr = slash - path - 2;
 461                                memmove(path, path+2, nr);
 462                                path[nr] = 0;
 463                                protocol = get_protocol(url);
 464                                host = path;
 465                                path = slash;
 466                        }
 467                }
 468        }
 469
 470        if (protocol == PROTO_GIT)
 471                return git_tcp_connect(fd, prog, host, path);
 472
 473        if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
 474                die("unable to create pipe pair for communication");
 475        pid = fork();
 476        if (!pid) {
 477                snprintf(command, sizeof(command), "%s %s", prog,
 478                         sq_quote(path));
 479                dup2(pipefd[1][0], 0);
 480                dup2(pipefd[0][1], 1);
 481                close(pipefd[0][0]);
 482                close(pipefd[0][1]);
 483                close(pipefd[1][0]);
 484                close(pipefd[1][1]);
 485                if (protocol == PROTO_SSH) {
 486                        const char *ssh, *ssh_basename;
 487                        ssh = getenv("GIT_SSH");
 488                        if (!ssh) ssh = "ssh";
 489                        ssh_basename = strrchr(ssh, '/');
 490                        if (!ssh_basename)
 491                                ssh_basename = ssh;
 492                        else
 493                                ssh_basename++;
 494                        execlp(ssh, ssh_basename, host, command, NULL);
 495                }
 496                else
 497                        execlp("sh", "sh", "-c", command, NULL);
 498                die("exec failed");
 499        }               
 500        fd[0] = pipefd[0][0];
 501        fd[1] = pipefd[1][1];
 502        close(pipefd[0][1]);
 503        close(pipefd[1][0]);
 504        return pid;
 505}
 506
 507int finish_connect(pid_t pid)
 508{
 509        int ret;
 510
 511        for (;;) {
 512                ret = waitpid(pid, NULL, 0);
 513                if (!ret)
 514                        break;
 515                if (errno != EINTR)
 516                        break;
 517        }
 518        return ret;
 519}