Andrew's git / gitweb.git / connect.c
?
connect.con commit Merge branch 'fixes' (f680493)
   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                        return 1;
  64        }
  65        die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
  66}
  67
  68int path_match(const char *path, int nr, char **match)
  69{
  70        int i;
  71        int pathlen = strlen(path);
  72
  73        for (i = 0; i < nr; i++) {
  74                char *s = match[i];
  75                int len = strlen(s);
  76
  77                if (!len || len > pathlen)
  78                        continue;
  79                if (memcmp(path + pathlen - len, s, len))
  80                        continue;
  81                if (pathlen > len && path[pathlen - len - 1] != '/')
  82                        continue;
  83                *s = 0;
  84                return 1;
  85        }
  86        return 0;
  87}
  88
  89struct refspec {
  90        char *src;
  91        char *dst;
  92        char force;
  93};
  94
  95/*
  96 * A:B means fast forward remote B with local A.
  97 * +A:B means overwrite remote B with local A.
  98 * +A is a shorthand for +A:A.
  99 * A is a shorthand for A:A.
 100 */
 101static struct refspec *parse_ref_spec(int nr_refspec, char **refspec)
 102{
 103        int i;
 104        struct refspec *rs = xcalloc(sizeof(*rs), (nr_refspec + 1));
 105        for (i = 0; i < nr_refspec; i++) {
 106                char *sp, *dp, *ep;
 107                sp = refspec[i];
 108                if (*sp == '+') {
 109                        rs[i].force = 1;
 110                        sp++;
 111                }
 112                ep = strchr(sp, ':');
 113                if (ep) {
 114                        dp = ep + 1;
 115                        *ep = 0;
 116                }
 117                else
 118                        dp = sp;
 119                rs[i].src = sp;
 120                rs[i].dst = dp;
 121        }
 122        rs[nr_refspec].src = rs[nr_refspec].dst = NULL;
 123        return rs;
 124}
 125
 126static int count_refspec_match(const char *pattern,
 127                               struct ref *refs,
 128                               struct ref **matched_ref)
 129{
 130        int match;
 131        int patlen = strlen(pattern);
 132
 133        for (match = 0; refs; refs = refs->next) {
 134                char *name = refs->name;
 135                int namelen = strlen(name);
 136                if (namelen < patlen ||
 137                    memcmp(name + namelen - patlen, pattern, patlen))
 138                        continue;
 139                if (namelen != patlen && name[namelen - patlen - 1] != '/')
 140                        continue;
 141                match++;
 142                *matched_ref = refs;
 143        }
 144        return match;
 145}
 146
 147static void link_dst_tail(struct ref *ref, struct ref ***tail)
 148{
 149        **tail = ref;
 150        *tail = &ref->next;
 151        **tail = NULL;
 152}
 153
 154static struct ref *try_explicit_object_name(const char *name)
 155{
 156        unsigned char sha1[20];
 157        struct ref *ref;
 158        int len;
 159        if (get_sha1(name, sha1))
 160                return NULL;
 161        len = strlen(name) + 1;
 162        ref = xcalloc(1, sizeof(*ref) + len);
 163        memcpy(ref->name, name, len);
 164        memcpy(ref->new_sha1, sha1, 20);
 165        return ref;
 166}
 167
 168static int match_explicit_refs(struct ref *src, struct ref *dst,
 169                               struct ref ***dst_tail, struct refspec *rs)
 170{
 171        int i, errs;
 172        for (i = errs = 0; rs[i].src; i++) {
 173                struct ref *matched_src, *matched_dst;
 174
 175                matched_src = matched_dst = NULL;
 176                switch (count_refspec_match(rs[i].src, src, &matched_src)) {
 177                case 1:
 178                        break;
 179                case 0:
 180                        /* The source could be in the get_sha1() format
 181                         * not a reference name.
 182                         */
 183                        matched_src = try_explicit_object_name(rs[i].src);
 184                        if (matched_src)
 185                                break;
 186                        errs = 1;
 187                        error("src refspec %s does not match any.",
 188                              rs[i].src);
 189                        break;
 190                default:
 191                        errs = 1;
 192                        error("src refspec %s matches more than one.",
 193                              rs[i].src);
 194                        break;
 195                }
 196                switch (count_refspec_match(rs[i].dst, dst, &matched_dst)) {
 197                case 1:
 198                        break;
 199                case 0:
 200                        if (!memcmp(rs[i].dst, "refs/", 5)) {
 201                                int len = strlen(rs[i].dst) + 1;
 202                                matched_dst = xcalloc(1, sizeof(*dst) + len);
 203                                memcpy(matched_dst->name, rs[i].dst, len);
 204                                link_dst_tail(matched_dst, dst_tail);
 205                        }
 206                        else if (!strcmp(rs[i].src, rs[i].dst) &&
 207                                 matched_src) {
 208                                /* pushing "master:master" when
 209                                 * remote does not have master yet.
 210                                 */
 211                                int len = strlen(matched_src->name) + 1;
 212                                matched_dst = xcalloc(1, sizeof(*dst) + len);
 213                                memcpy(matched_dst->name, matched_src->name,
 214                                       len);
 215                                link_dst_tail(matched_dst, dst_tail);
 216                        }
 217                        else {
 218                                errs = 1;
 219                                error("dst refspec %s does not match any "
 220                                      "existing ref on the remote and does "
 221                                      "not start with refs/.", rs[i].dst);
 222                        }
 223                        break;
 224                default:
 225                        errs = 1;
 226                        error("dst refspec %s matches more than one.",
 227                              rs[i].dst);
 228                        break;
 229                }
 230                if (errs)
 231                        continue;
 232                if (matched_dst->peer_ref) {
 233                        errs = 1;
 234                        error("dst ref %s receives from more than one src.",
 235                              matched_dst->name);
 236                }
 237                else {
 238                        matched_dst->peer_ref = matched_src;
 239                        matched_dst->force = rs[i].force;
 240                }
 241        }
 242        return -errs;
 243}
 244
 245static struct ref *find_ref_by_name(struct ref *list, const char *name)
 246{
 247        for ( ; list; list = list->next)
 248                if (!strcmp(list->name, name))
 249                        return list;
 250        return NULL;
 251}
 252
 253int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 254               int nr_refspec, char **refspec, int all)
 255{
 256        struct refspec *rs = parse_ref_spec(nr_refspec, refspec);
 257
 258        if (nr_refspec)
 259                return match_explicit_refs(src, dst, dst_tail, rs);
 260
 261        /* pick the remainder */
 262        for ( ; src; src = src->next) {
 263                struct ref *dst_peer;
 264                if (src->peer_ref)
 265                        continue;
 266                dst_peer = find_ref_by_name(dst, src->name);
 267                if ((dst_peer && dst_peer->peer_ref) || (!dst_peer && !all))
 268                        continue;
 269                if (!dst_peer) {
 270                        /* Create a new one and link it */
 271                        int len = strlen(src->name) + 1;
 272                        dst_peer = xcalloc(1, sizeof(*dst_peer) + len);
 273                        memcpy(dst_peer->name, src->name, len);
 274                        memcpy(dst_peer->new_sha1, src->new_sha1, 20);
 275                        link_dst_tail(dst_peer, dst_tail);
 276                }
 277                dst_peer->peer_ref = src;
 278        }
 279        return 0;
 280}
 281
 282enum protocol {
 283        PROTO_LOCAL = 1,
 284        PROTO_SSH,
 285        PROTO_GIT,
 286};
 287
 288static enum protocol get_protocol(const char *name)
 289{
 290        if (!strcmp(name, "ssh"))
 291                return PROTO_SSH;
 292        if (!strcmp(name, "git"))
 293                return PROTO_GIT;
 294        die("I don't handle protocol '%s'", name);
 295}
 296
 297#define STR_(s) # s
 298#define STR(s)  STR_(s)
 299
 300static int git_tcp_connect(int fd[2], const char *prog, char *host, char *path)
 301{
 302        int sockfd = -1;
 303        char *colon, *end;
 304        char *port = STR(DEFAULT_GIT_PORT);
 305        struct addrinfo hints, *ai0, *ai;
 306        int gai;
 307
 308        if (host[0] == '[') {
 309                end = strchr(host + 1, ']');
 310                if (end) {
 311                        *end = 0;
 312                        end++;
 313                        host++;
 314                } else
 315                        end = host;
 316        } else
 317                end = host;
 318        colon = strchr(end, ':');
 319
 320        if (colon) {
 321                *colon = 0;
 322                port = colon + 1;
 323        }
 324
 325        memset(&hints, 0, sizeof(hints));
 326        hints.ai_socktype = SOCK_STREAM;
 327        hints.ai_protocol = IPPROTO_TCP;
 328
 329        gai = getaddrinfo(host, port, &hints, &ai);
 330        if (gai)
 331                die("Unable to look up %s (%s)", host, gai_strerror(gai));
 332
 333        for (ai0 = ai; ai; ai = ai->ai_next) {
 334                sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 335                if (sockfd < 0)
 336                        continue;
 337                if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
 338                        close(sockfd);
 339                        sockfd = -1;
 340                        continue;
 341                }
 342                break;
 343        }
 344
 345        freeaddrinfo(ai0);
 346
 347        if (sockfd < 0)
 348                die("unable to connect a socket (%s)", strerror(errno));
 349
 350        fd[0] = sockfd;
 351        fd[1] = sockfd;
 352        packet_write(sockfd, "%s %s\n", prog, path);
 353        return 0;
 354}
 355
 356/*
 357 * Yeah, yeah, fixme. Need to pass in the heads etc.
 358 */
 359int git_connect(int fd[2], char *url, const char *prog)
 360{
 361        char command[1024];
 362        char *host, *path;
 363        char *colon;
 364        int pipefd[2][2];
 365        pid_t pid;
 366        enum protocol protocol;
 367
 368        host = NULL;
 369        path = url;
 370        colon = strchr(url, ':');
 371        protocol = PROTO_LOCAL;
 372        if (colon) {
 373                *colon = 0;
 374                host = url;
 375                path = colon+1;
 376                protocol = PROTO_SSH;
 377                if (!memcmp(path, "//", 2)) {
 378                        char *slash = strchr(path + 2, '/');
 379                        if (slash) {
 380                                int nr = slash - path - 2;
 381                                memmove(path, path+2, nr);
 382                                path[nr] = 0;
 383                                protocol = get_protocol(url);
 384                                host = path;
 385                                path = slash;
 386                        }
 387                }
 388        }
 389
 390        if (protocol == PROTO_GIT)
 391                return git_tcp_connect(fd, prog, host, path);
 392
 393        if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
 394                die("unable to create pipe pair for communication");
 395        pid = fork();
 396        if (!pid) {
 397                snprintf(command, sizeof(command), "%s %s", prog,
 398                         sq_quote(path));
 399                dup2(pipefd[1][0], 0);
 400                dup2(pipefd[0][1], 1);
 401                close(pipefd[0][0]);
 402                close(pipefd[0][1]);
 403                close(pipefd[1][0]);
 404                close(pipefd[1][1]);
 405                if (protocol == PROTO_SSH) {
 406                        const char *ssh, *ssh_basename;
 407                        ssh = getenv("GIT_SSH");
 408                        if (!ssh) ssh = "ssh";
 409                        ssh_basename = strrchr(ssh, '/');
 410                        if (!ssh_basename)
 411                                ssh_basename = ssh;
 412                        else
 413                                ssh_basename++;
 414                        execlp(ssh, ssh_basename, host, command, NULL);
 415                }
 416                else
 417                        execlp("sh", "sh", "-c", command, NULL);
 418                die("exec failed");
 419        }               
 420        fd[0] = pipefd[0][0];
 421        fd[1] = pipefd[1][1];
 422        close(pipefd[0][1]);
 423        close(pipefd[1][0]);
 424        return pid;
 425}
 426
 427int finish_connect(pid_t pid)
 428{
 429        int ret;
 430
 431        for (;;) {
 432                ret = waitpid(pid, NULL, 0);
 433                if (!ret)
 434                        break;
 435                if (errno != EINTR)
 436                        break;
 437        }
 438        return ret;
 439}