Andrew's git / gitweb.git / http-backend.c
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http-backend.con commit packfile: add repository argument to prepare_packed_git (6fdb4e9)
   1#include "cache.h"
   2#include "config.h"
   3#include "repository.h"
   4#include "refs.h"
   5#include "pkt-line.h"
   6#include "object.h"
   7#include "tag.h"
   8#include "exec_cmd.h"
   9#include "run-command.h"
  10#include "string-list.h"
  11#include "url.h"
  12#include "argv-array.h"
  13#include "packfile.h"
  14#include "object-store.h"
  15
  16static const char content_type[] = "Content-Type";
  17static const char content_length[] = "Content-Length";
  18static const char last_modified[] = "Last-Modified";
  19static int getanyfile = 1;
  20static unsigned long max_request_buffer = 10 * 1024 * 1024;
  21
  22static struct string_list *query_params;
  23
  24struct rpc_service {
  25        const char *name;
  26        const char *config_name;
  27        unsigned buffer_input : 1;
  28        signed enabled : 2;
  29};
  30
  31static struct rpc_service rpc_service[] = {
  32        { "upload-pack", "uploadpack", 1, 1 },
  33        { "receive-pack", "receivepack", 0, -1 },
  34};
  35
  36static struct string_list *get_parameters(void)
  37{
  38        if (!query_params) {
  39                const char *query = getenv("QUERY_STRING");
  40
  41                query_params = xcalloc(1, sizeof(*query_params));
  42                while (query && *query) {
  43                        char *name = url_decode_parameter_name(&query);
  44                        char *value = url_decode_parameter_value(&query);
  45                        struct string_list_item *i;
  46
  47                        i = string_list_lookup(query_params, name);
  48                        if (!i)
  49                                i = string_list_insert(query_params, name);
  50                        else
  51                                free(i->util);
  52                        i->util = value;
  53                }
  54        }
  55        return query_params;
  56}
  57
  58static const char *get_parameter(const char *name)
  59{
  60        struct string_list_item *i;
  61        i = string_list_lookup(get_parameters(), name);
  62        return i ? i->util : NULL;
  63}
  64
  65__attribute__((format (printf, 2, 3)))
  66static void format_write(int fd, const char *fmt, ...)
  67{
  68        static char buffer[1024];
  69
  70        va_list args;
  71        unsigned n;
  72
  73        va_start(args, fmt);
  74        n = vsnprintf(buffer, sizeof(buffer), fmt, args);
  75        va_end(args);
  76        if (n >= sizeof(buffer))
  77                die("protocol error: impossibly long line");
  78
  79        write_or_die(fd, buffer, n);
  80}
  81
  82static void http_status(struct strbuf *hdr, unsigned code, const char *msg)
  83{
  84        strbuf_addf(hdr, "Status: %u %s\r\n", code, msg);
  85}
  86
  87static void hdr_str(struct strbuf *hdr, const char *name, const char *value)
  88{
  89        strbuf_addf(hdr, "%s: %s\r\n", name, value);
  90}
  91
  92static void hdr_int(struct strbuf *hdr, const char *name, uintmax_t value)
  93{
  94        strbuf_addf(hdr, "%s: %" PRIuMAX "\r\n", name, value);
  95}
  96
  97static void hdr_date(struct strbuf *hdr, const char *name, timestamp_t when)
  98{
  99        const char *value = show_date(when, 0, DATE_MODE(RFC2822));
 100        hdr_str(hdr, name, value);
 101}
 102
 103static void hdr_nocache(struct strbuf *hdr)
 104{
 105        hdr_str(hdr, "Expires", "Fri, 01 Jan 1980 00:00:00 GMT");
 106        hdr_str(hdr, "Pragma", "no-cache");
 107        hdr_str(hdr, "Cache-Control", "no-cache, max-age=0, must-revalidate");
 108}
 109
 110static void hdr_cache_forever(struct strbuf *hdr)
 111{
 112        timestamp_t now = time(NULL);
 113        hdr_date(hdr, "Date", now);
 114        hdr_date(hdr, "Expires", now + 31536000);
 115        hdr_str(hdr, "Cache-Control", "public, max-age=31536000");
 116}
 117
 118static void end_headers(struct strbuf *hdr)
 119{
 120        strbuf_add(hdr, "\r\n", 2);
 121        write_or_die(1, hdr->buf, hdr->len);
 122        strbuf_release(hdr);
 123}
 124
 125__attribute__((format (printf, 2, 3)))
 126static NORETURN void not_found(struct strbuf *hdr, const char *err, ...)
 127{
 128        va_list params;
 129
 130        http_status(hdr, 404, "Not Found");
 131        hdr_nocache(hdr);
 132        end_headers(hdr);
 133
 134        va_start(params, err);
 135        if (err && *err)
 136                vfprintf(stderr, err, params);
 137        va_end(params);
 138        exit(0);
 139}
 140
 141__attribute__((format (printf, 2, 3)))
 142static NORETURN void forbidden(struct strbuf *hdr, const char *err, ...)
 143{
 144        va_list params;
 145
 146        http_status(hdr, 403, "Forbidden");
 147        hdr_nocache(hdr);
 148        end_headers(hdr);
 149
 150        va_start(params, err);
 151        if (err && *err)
 152                vfprintf(stderr, err, params);
 153        va_end(params);
 154        exit(0);
 155}
 156
 157static void select_getanyfile(struct strbuf *hdr)
 158{
 159        if (!getanyfile)
 160                forbidden(hdr, "Unsupported service: getanyfile");
 161}
 162
 163static void send_strbuf(struct strbuf *hdr,
 164                        const char *type, struct strbuf *buf)
 165{
 166        hdr_int(hdr, content_length, buf->len);
 167        hdr_str(hdr, content_type, type);
 168        end_headers(hdr);
 169        write_or_die(1, buf->buf, buf->len);
 170}
 171
 172static void send_local_file(struct strbuf *hdr, const char *the_type,
 173                                const char *name)
 174{
 175        char *p = git_pathdup("%s", name);
 176        size_t buf_alloc = 8192;
 177        char *buf = xmalloc(buf_alloc);
 178        int fd;
 179        struct stat sb;
 180
 181        fd = open(p, O_RDONLY);
 182        if (fd < 0)
 183                not_found(hdr, "Cannot open '%s': %s", p, strerror(errno));
 184        if (fstat(fd, &sb) < 0)
 185                die_errno("Cannot stat '%s'", p);
 186
 187        hdr_int(hdr, content_length, sb.st_size);
 188        hdr_str(hdr, content_type, the_type);
 189        hdr_date(hdr, last_modified, sb.st_mtime);
 190        end_headers(hdr);
 191
 192        for (;;) {
 193                ssize_t n = xread(fd, buf, buf_alloc);
 194                if (n < 0)
 195                        die_errno("Cannot read '%s'", p);
 196                if (!n)
 197                        break;
 198                write_or_die(1, buf, n);
 199        }
 200        close(fd);
 201        free(buf);
 202        free(p);
 203}
 204
 205static void get_text_file(struct strbuf *hdr, char *name)
 206{
 207        select_getanyfile(hdr);
 208        hdr_nocache(hdr);
 209        send_local_file(hdr, "text/plain", name);
 210}
 211
 212static void get_loose_object(struct strbuf *hdr, char *name)
 213{
 214        select_getanyfile(hdr);
 215        hdr_cache_forever(hdr);
 216        send_local_file(hdr, "application/x-git-loose-object", name);
 217}
 218
 219static void get_pack_file(struct strbuf *hdr, char *name)
 220{
 221        select_getanyfile(hdr);
 222        hdr_cache_forever(hdr);
 223        send_local_file(hdr, "application/x-git-packed-objects", name);
 224}
 225
 226static void get_idx_file(struct strbuf *hdr, char *name)
 227{
 228        select_getanyfile(hdr);
 229        hdr_cache_forever(hdr);
 230        send_local_file(hdr, "application/x-git-packed-objects-toc", name);
 231}
 232
 233static void http_config(void)
 234{
 235        int i, value = 0;
 236        struct strbuf var = STRBUF_INIT;
 237
 238        git_config_get_bool("http.getanyfile", &getanyfile);
 239        git_config_get_ulong("http.maxrequestbuffer", &max_request_buffer);
 240
 241        for (i = 0; i < ARRAY_SIZE(rpc_service); i++) {
 242                struct rpc_service *svc = &rpc_service[i];
 243                strbuf_addf(&var, "http.%s", svc->config_name);
 244                if (!git_config_get_bool(var.buf, &value))
 245                        svc->enabled = value;
 246                strbuf_reset(&var);
 247        }
 248
 249        strbuf_release(&var);
 250}
 251
 252static struct rpc_service *select_service(struct strbuf *hdr, const char *name)
 253{
 254        const char *svc_name;
 255        struct rpc_service *svc = NULL;
 256        int i;
 257
 258        if (!skip_prefix(name, "git-", &svc_name))
 259                forbidden(hdr, "Unsupported service: '%s'", name);
 260
 261        for (i = 0; i < ARRAY_SIZE(rpc_service); i++) {
 262                struct rpc_service *s = &rpc_service[i];
 263                if (!strcmp(s->name, svc_name)) {
 264                        svc = s;
 265                        break;
 266                }
 267        }
 268
 269        if (!svc)
 270                forbidden(hdr, "Unsupported service: '%s'", name);
 271
 272        if (svc->enabled < 0) {
 273                const char *user = getenv("REMOTE_USER");
 274                svc->enabled = (user && *user) ? 1 : 0;
 275        }
 276        if (!svc->enabled)
 277                forbidden(hdr, "Service not enabled: '%s'", svc->name);
 278        return svc;
 279}
 280
 281/*
 282 * This is basically strbuf_read(), except that if we
 283 * hit max_request_buffer we die (we'd rather reject a
 284 * maliciously large request than chew up infinite memory).
 285 */
 286static ssize_t read_request(int fd, unsigned char **out)
 287{
 288        size_t len = 0, alloc = 8192;
 289        unsigned char *buf = xmalloc(alloc);
 290
 291        if (max_request_buffer < alloc)
 292                max_request_buffer = alloc;
 293
 294        while (1) {
 295                ssize_t cnt;
 296
 297                cnt = read_in_full(fd, buf + len, alloc - len);
 298                if (cnt < 0) {
 299                        free(buf);
 300                        return -1;
 301                }
 302
 303                /* partial read from read_in_full means we hit EOF */
 304                len += cnt;
 305                if (len < alloc) {
 306                        *out = buf;
 307                        return len;
 308                }
 309
 310                /* otherwise, grow and try again (if we can) */
 311                if (alloc == max_request_buffer)
 312                        die("request was larger than our maximum size (%lu);"
 313                            " try setting GIT_HTTP_MAX_REQUEST_BUFFER",
 314                            max_request_buffer);
 315
 316                alloc = alloc_nr(alloc);
 317                if (alloc > max_request_buffer)
 318                        alloc = max_request_buffer;
 319                REALLOC_ARRAY(buf, alloc);
 320        }
 321}
 322
 323static void inflate_request(const char *prog_name, int out, int buffer_input)
 324{
 325        git_zstream stream;
 326        unsigned char *full_request = NULL;
 327        unsigned char in_buf[8192];
 328        unsigned char out_buf[8192];
 329        unsigned long cnt = 0;
 330
 331        memset(&stream, 0, sizeof(stream));
 332        git_inflate_init_gzip_only(&stream);
 333
 334        while (1) {
 335                ssize_t n;
 336
 337                if (buffer_input) {
 338                        if (full_request)
 339                                n = 0; /* nothing left to read */
 340                        else
 341                                n = read_request(0, &full_request);
 342                        stream.next_in = full_request;
 343                } else {
 344                        n = xread(0, in_buf, sizeof(in_buf));
 345                        stream.next_in = in_buf;
 346                }
 347
 348                if (n <= 0)
 349                        die("request ended in the middle of the gzip stream");
 350                stream.avail_in = n;
 351
 352                while (0 < stream.avail_in) {
 353                        int ret;
 354
 355                        stream.next_out = out_buf;
 356                        stream.avail_out = sizeof(out_buf);
 357
 358                        ret = git_inflate(&stream, Z_NO_FLUSH);
 359                        if (ret != Z_OK && ret != Z_STREAM_END)
 360                                die("zlib error inflating request, result %d", ret);
 361
 362                        n = stream.total_out - cnt;
 363                        if (write_in_full(out, out_buf, n) < 0)
 364                                die("%s aborted reading request", prog_name);
 365                        cnt += n;
 366
 367                        if (ret == Z_STREAM_END)
 368                                goto done;
 369                }
 370        }
 371
 372done:
 373        git_inflate_end(&stream);
 374        close(out);
 375        free(full_request);
 376}
 377
 378static void copy_request(const char *prog_name, int out)
 379{
 380        unsigned char *buf;
 381        ssize_t n = read_request(0, &buf);
 382        if (n < 0)
 383                die_errno("error reading request body");
 384        if (write_in_full(out, buf, n) < 0)
 385                die("%s aborted reading request", prog_name);
 386        close(out);
 387        free(buf);
 388}
 389
 390static void run_service(const char **argv, int buffer_input)
 391{
 392        const char *encoding = getenv("HTTP_CONTENT_ENCODING");
 393        const char *user = getenv("REMOTE_USER");
 394        const char *host = getenv("REMOTE_ADDR");
 395        int gzipped_request = 0;
 396        struct child_process cld = CHILD_PROCESS_INIT;
 397
 398        if (encoding && !strcmp(encoding, "gzip"))
 399                gzipped_request = 1;
 400        else if (encoding && !strcmp(encoding, "x-gzip"))
 401                gzipped_request = 1;
 402
 403        if (!user || !*user)
 404                user = "anonymous";
 405        if (!host || !*host)
 406                host = "(none)";
 407
 408        if (!getenv("GIT_COMMITTER_NAME"))
 409                argv_array_pushf(&cld.env_array, "GIT_COMMITTER_NAME=%s", user);
 410        if (!getenv("GIT_COMMITTER_EMAIL"))
 411                argv_array_pushf(&cld.env_array,
 412                                 "GIT_COMMITTER_EMAIL=%s@http.%s", user, host);
 413
 414        cld.argv = argv;
 415        if (buffer_input || gzipped_request)
 416                cld.in = -1;
 417        cld.git_cmd = 1;
 418        if (start_command(&cld))
 419                exit(1);
 420
 421        close(1);
 422        if (gzipped_request)
 423                inflate_request(argv[0], cld.in, buffer_input);
 424        else if (buffer_input)
 425                copy_request(argv[0], cld.in);
 426        else
 427                close(0);
 428
 429        if (finish_command(&cld))
 430                exit(1);
 431}
 432
 433static int show_text_ref(const char *name, const struct object_id *oid,
 434                         int flag, void *cb_data)
 435{
 436        const char *name_nons = strip_namespace(name);
 437        struct strbuf *buf = cb_data;
 438        struct object *o = parse_object(oid);
 439        if (!o)
 440                return 0;
 441
 442        strbuf_addf(buf, "%s\t%s\n", oid_to_hex(oid), name_nons);
 443        if (o->type == OBJ_TAG) {
 444                o = deref_tag(o, name, 0);
 445                if (!o)
 446                        return 0;
 447                strbuf_addf(buf, "%s\t%s^{}\n", oid_to_hex(&o->oid),
 448                            name_nons);
 449        }
 450        return 0;
 451}
 452
 453static void get_info_refs(struct strbuf *hdr, char *arg)
 454{
 455        const char *service_name = get_parameter("service");
 456        struct strbuf buf = STRBUF_INIT;
 457
 458        hdr_nocache(hdr);
 459
 460        if (service_name) {
 461                const char *argv[] = {NULL /* service name */,
 462                        "--stateless-rpc", "--advertise-refs",
 463                        ".", NULL};
 464                struct rpc_service *svc = select_service(hdr, service_name);
 465
 466                strbuf_addf(&buf, "application/x-git-%s-advertisement",
 467                        svc->name);
 468                hdr_str(hdr, content_type, buf.buf);
 469                end_headers(hdr);
 470
 471                packet_write_fmt(1, "# service=git-%s\n", svc->name);
 472                packet_flush(1);
 473
 474                argv[0] = svc->name;
 475                run_service(argv, 0);
 476
 477        } else {
 478                select_getanyfile(hdr);
 479                for_each_namespaced_ref(show_text_ref, &buf);
 480                send_strbuf(hdr, "text/plain", &buf);
 481        }
 482        strbuf_release(&buf);
 483}
 484
 485static int show_head_ref(const char *refname, const struct object_id *oid,
 486                         int flag, void *cb_data)
 487{
 488        struct strbuf *buf = cb_data;
 489
 490        if (flag & REF_ISSYMREF) {
 491                const char *target = resolve_ref_unsafe(refname,
 492                                                        RESOLVE_REF_READING,
 493                                                        NULL, NULL);
 494
 495                if (target)
 496                        strbuf_addf(buf, "ref: %s\n", strip_namespace(target));
 497        } else {
 498                strbuf_addf(buf, "%s\n", oid_to_hex(oid));
 499        }
 500
 501        return 0;
 502}
 503
 504static void get_head(struct strbuf *hdr, char *arg)
 505{
 506        struct strbuf buf = STRBUF_INIT;
 507
 508        select_getanyfile(hdr);
 509        head_ref_namespaced(show_head_ref, &buf);
 510        send_strbuf(hdr, "text/plain", &buf);
 511        strbuf_release(&buf);
 512}
 513
 514static void get_info_packs(struct strbuf *hdr, char *arg)
 515{
 516        size_t objdirlen = strlen(get_object_directory());
 517        struct strbuf buf = STRBUF_INIT;
 518        struct packed_git *p;
 519        size_t cnt = 0;
 520
 521        select_getanyfile(hdr);
 522        prepare_packed_git(the_repository);
 523        for (p = get_packed_git(the_repository); p; p = p->next) {
 524                if (p->pack_local)
 525                        cnt++;
 526        }
 527
 528        strbuf_grow(&buf, cnt * 53 + 2);
 529        for (p = get_packed_git(the_repository); p; p = p->next) {
 530                if (p->pack_local)
 531                        strbuf_addf(&buf, "P %s\n", p->pack_name + objdirlen + 6);
 532        }
 533        strbuf_addch(&buf, '\n');
 534
 535        hdr_nocache(hdr);
 536        send_strbuf(hdr, "text/plain; charset=utf-8", &buf);
 537        strbuf_release(&buf);
 538}
 539
 540static void check_content_type(struct strbuf *hdr, const char *accepted_type)
 541{
 542        const char *actual_type = getenv("CONTENT_TYPE");
 543
 544        if (!actual_type)
 545                actual_type = "";
 546
 547        if (strcmp(actual_type, accepted_type)) {
 548                http_status(hdr, 415, "Unsupported Media Type");
 549                hdr_nocache(hdr);
 550                end_headers(hdr);
 551                format_write(1,
 552                        "Expected POST with Content-Type '%s',"
 553                        " but received '%s' instead.\n",
 554                        accepted_type, actual_type);
 555                exit(0);
 556        }
 557}
 558
 559static void service_rpc(struct strbuf *hdr, char *service_name)
 560{
 561        const char *argv[] = {NULL, "--stateless-rpc", ".", NULL};
 562        struct rpc_service *svc = select_service(hdr, service_name);
 563        struct strbuf buf = STRBUF_INIT;
 564
 565        strbuf_reset(&buf);
 566        strbuf_addf(&buf, "application/x-git-%s-request", svc->name);
 567        check_content_type(hdr, buf.buf);
 568
 569        hdr_nocache(hdr);
 570
 571        strbuf_reset(&buf);
 572        strbuf_addf(&buf, "application/x-git-%s-result", svc->name);
 573        hdr_str(hdr, content_type, buf.buf);
 574
 575        end_headers(hdr);
 576
 577        argv[0] = svc->name;
 578        run_service(argv, svc->buffer_input);
 579        strbuf_release(&buf);
 580}
 581
 582static int dead;
 583static NORETURN void die_webcgi(const char *err, va_list params)
 584{
 585        if (dead <= 1) {
 586                struct strbuf hdr = STRBUF_INIT;
 587
 588                vreportf("fatal: ", err, params);
 589
 590                http_status(&hdr, 500, "Internal Server Error");
 591                hdr_nocache(&hdr);
 592                end_headers(&hdr);
 593        }
 594        exit(0); /* we successfully reported a failure ;-) */
 595}
 596
 597static int die_webcgi_recursing(void)
 598{
 599        return dead++ > 1;
 600}
 601
 602static char* getdir(void)
 603{
 604        struct strbuf buf = STRBUF_INIT;
 605        char *pathinfo = getenv("PATH_INFO");
 606        char *root = getenv("GIT_PROJECT_ROOT");
 607        char *path = getenv("PATH_TRANSLATED");
 608
 609        if (root && *root) {
 610                if (!pathinfo || !*pathinfo)
 611                        die("GIT_PROJECT_ROOT is set but PATH_INFO is not");
 612                if (daemon_avoid_alias(pathinfo))
 613                        die("'%s': aliased", pathinfo);
 614                end_url_with_slash(&buf, root);
 615                if (pathinfo[0] == '/')
 616                        pathinfo++;
 617                strbuf_addstr(&buf, pathinfo);
 618                return strbuf_detach(&buf, NULL);
 619        } else if (path && *path) {
 620                return xstrdup(path);
 621        } else
 622                die("No GIT_PROJECT_ROOT or PATH_TRANSLATED from server");
 623        return NULL;
 624}
 625
 626static struct service_cmd {
 627        const char *method;
 628        const char *pattern;
 629        void (*imp)(struct strbuf *, char *);
 630} services[] = {
 631        {"GET", "/HEAD$", get_head},
 632        {"GET", "/info/refs$", get_info_refs},
 633        {"GET", "/objects/info/alternates$", get_text_file},
 634        {"GET", "/objects/info/http-alternates$", get_text_file},
 635        {"GET", "/objects/info/packs$", get_info_packs},
 636        {"GET", "/objects/[0-9a-f]{2}/[0-9a-f]{38}$", get_loose_object},
 637        {"GET", "/objects/pack/pack-[0-9a-f]{40}\\.pack$", get_pack_file},
 638        {"GET", "/objects/pack/pack-[0-9a-f]{40}\\.idx$", get_idx_file},
 639
 640        {"POST", "/git-upload-pack$", service_rpc},
 641        {"POST", "/git-receive-pack$", service_rpc}
 642};
 643
 644static int bad_request(struct strbuf *hdr, const struct service_cmd *c)
 645{
 646        const char *proto = getenv("SERVER_PROTOCOL");
 647
 648        if (proto && !strcmp(proto, "HTTP/1.1")) {
 649                http_status(hdr, 405, "Method Not Allowed");
 650                hdr_str(hdr, "Allow",
 651                        !strcmp(c->method, "GET") ? "GET, HEAD" : c->method);
 652        } else
 653                http_status(hdr, 400, "Bad Request");
 654        hdr_nocache(hdr);
 655        end_headers(hdr);
 656        return 0;
 657}
 658
 659int cmd_main(int argc, const char **argv)
 660{
 661        char *method = getenv("REQUEST_METHOD");
 662        char *dir;
 663        struct service_cmd *cmd = NULL;
 664        char *cmd_arg = NULL;
 665        int i;
 666        struct strbuf hdr = STRBUF_INIT;
 667
 668        set_die_routine(die_webcgi);
 669        set_die_is_recursing_routine(die_webcgi_recursing);
 670
 671        if (!method)
 672                die("No REQUEST_METHOD from server");
 673        if (!strcmp(method, "HEAD"))
 674                method = "GET";
 675        dir = getdir();
 676
 677        for (i = 0; i < ARRAY_SIZE(services); i++) {
 678                struct service_cmd *c = &services[i];
 679                regex_t re;
 680                regmatch_t out[1];
 681
 682                if (regcomp(&re, c->pattern, REG_EXTENDED))
 683                        die("Bogus regex in service table: %s", c->pattern);
 684                if (!regexec(&re, dir, 1, out, 0)) {
 685                        size_t n;
 686
 687                        if (strcmp(method, c->method))
 688                                return bad_request(&hdr, c);
 689
 690                        cmd = c;
 691                        n = out[0].rm_eo - out[0].rm_so;
 692                        cmd_arg = xmemdupz(dir + out[0].rm_so + 1, n - 1);
 693                        dir[out[0].rm_so] = 0;
 694                        break;
 695                }
 696                regfree(&re);
 697        }
 698
 699        if (!cmd)
 700                not_found(&hdr, "Request not supported: '%s'", dir);
 701
 702        setup_path();
 703        if (!enter_repo(dir, 0))
 704                not_found(&hdr, "Not a git repository: '%s'", dir);
 705        if (!getenv("GIT_HTTP_EXPORT_ALL") &&
 706            access("git-daemon-export-ok", F_OK) )
 707                not_found(&hdr, "Repository not exported: '%s'", dir);
 708
 709        http_config();
 710        max_request_buffer = git_env_ulong("GIT_HTTP_MAX_REQUEST_BUFFER",
 711                                           max_request_buffer);
 712
 713        cmd->imp(&hdr, cmd_arg);
 714        return 0;
 715}