Code

Merge branch 'js/maint-send-pack-stateless-rpc-deadlock-fix'
authorJunio C Hamano <gitster@pobox.com>
Fri, 13 May 2011 18:02:29 +0000 (11:02 -0700)
committerJunio C Hamano <gitster@pobox.com>
Fri, 13 May 2011 18:02:29 +0000 (11:02 -0700)
* js/maint-send-pack-stateless-rpc-deadlock-fix:
  send-pack: unbreak push over stateless rpc
  send-pack: avoid deadlock when pack-object dies early

1  2 
builtin/send-pack.c

index 8b0911c0d2ac5a60f8a3c7a43e7960617ded9d7a,0000000000000000000000000000000000000000..4ac2ca984ff36588c68274f10f131ef88023d622
mode 100644,000000..100644
--- /dev/null
@@@ -1,534 -1,0 +1,539 @@@
 +#include "builtin.h"
 +#include "commit.h"
 +#include "refs.h"
 +#include "pkt-line.h"
 +#include "sideband.h"
 +#include "run-command.h"
 +#include "remote.h"
 +#include "send-pack.h"
 +#include "quote.h"
 +#include "transport.h"
 +
 +static const char send_pack_usage[] =
 +"git send-pack [--all | --mirror] [--dry-run] [--force] [--receive-pack=<git-receive-pack>] [--verbose] [--thin] [<host>:]<directory> [<ref>...]\n"
 +"  --all and explicit <ref> specification are mutually exclusive.";
 +
 +static struct send_pack_args args;
 +
 +static int feed_object(const unsigned char *sha1, int fd, int negative)
 +{
 +      char buf[42];
 +
 +      if (negative && !has_sha1_file(sha1))
 +              return 1;
 +
 +      memcpy(buf + negative, sha1_to_hex(sha1), 40);
 +      if (negative)
 +              buf[0] = '^';
 +      buf[40 + negative] = '\n';
 +      return write_or_whine(fd, buf, 41 + negative, "send-pack: send refs");
 +}
 +
 +/*
 + * Make a pack stream and spit it out into file descriptor fd
 + */
 +static int pack_objects(int fd, struct ref *refs, struct extra_have_objects *extra, struct send_pack_args *args)
 +{
 +      /*
 +       * The child becomes pack-objects --revs; we feed
 +       * the revision parameters to it via its stdin and
 +       * let its stdout go back to the other end.
 +       */
 +      const char *argv[] = {
 +              "pack-objects",
 +              "--all-progress-implied",
 +              "--revs",
 +              "--stdout",
 +              NULL,
 +              NULL,
 +              NULL,
 +              NULL,
 +              NULL,
 +      };
 +      struct child_process po;
 +      int i;
 +
 +      i = 4;
 +      if (args->use_thin_pack)
 +              argv[i++] = "--thin";
 +      if (args->use_ofs_delta)
 +              argv[i++] = "--delta-base-offset";
 +      if (args->quiet)
 +              argv[i++] = "-q";
 +      if (args->progress)
 +              argv[i++] = "--progress";
 +      memset(&po, 0, sizeof(po));
 +      po.argv = argv;
 +      po.in = -1;
 +      po.out = args->stateless_rpc ? -1 : fd;
 +      po.git_cmd = 1;
 +      if (start_command(&po))
 +              die_errno("git pack-objects failed");
 +
 +      /*
 +       * We feed the pack-objects we just spawned with revision
 +       * parameters by writing to the pipe.
 +       */
 +      for (i = 0; i < extra->nr; i++)
 +              if (!feed_object(extra->array[i], po.in, 1))
 +                      break;
 +
 +      while (refs) {
 +              if (!is_null_sha1(refs->old_sha1) &&
 +                  !feed_object(refs->old_sha1, po.in, 1))
 +                      break;
 +              if (!is_null_sha1(refs->new_sha1) &&
 +                  !feed_object(refs->new_sha1, po.in, 0))
 +                      break;
 +              refs = refs->next;
 +      }
 +
 +      close(po.in);
 +
 +      if (args->stateless_rpc) {
 +              char *buf = xmalloc(LARGE_PACKET_MAX);
 +              while (1) {
 +                      ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
 +                      if (n <= 0)
 +                              break;
 +                      send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
 +              }
 +              free(buf);
 +              close(po.out);
 +              po.out = -1;
 +      }
 +
 +      if (finish_command(&po))
 +              return -1;
 +      return 0;
 +}
 +
 +static int receive_status(int in, struct ref *refs)
 +{
 +      struct ref *hint;
 +      char line[1000];
 +      int ret = 0;
 +      int len = packet_read_line(in, line, sizeof(line));
 +      if (len < 10 || memcmp(line, "unpack ", 7))
 +              return error("did not receive remote status");
 +      if (memcmp(line, "unpack ok\n", 10)) {
 +              char *p = line + strlen(line) - 1;
 +              if (*p == '\n')
 +                      *p = '\0';
 +              error("unpack failed: %s", line + 7);
 +              ret = -1;
 +      }
 +      hint = NULL;
 +      while (1) {
 +              char *refname;
 +              char *msg;
 +              len = packet_read_line(in, line, sizeof(line));
 +              if (!len)
 +                      break;
 +              if (len < 3 ||
 +                  (memcmp(line, "ok ", 3) && memcmp(line, "ng ", 3))) {
 +                      fprintf(stderr, "protocol error: %s\n", line);
 +                      ret = -1;
 +                      break;
 +              }
 +
 +              line[strlen(line)-1] = '\0';
 +              refname = line + 3;
 +              msg = strchr(refname, ' ');
 +              if (msg)
 +                      *msg++ = '\0';
 +
 +              /* first try searching at our hint, falling back to all refs */
 +              if (hint)
 +                      hint = find_ref_by_name(hint, refname);
 +              if (!hint)
 +                      hint = find_ref_by_name(refs, refname);
 +              if (!hint) {
 +                      warning("remote reported status on unknown ref: %s",
 +                                      refname);
 +                      continue;
 +              }
 +              if (hint->status != REF_STATUS_EXPECTING_REPORT) {
 +                      warning("remote reported status on unexpected ref: %s",
 +                                      refname);
 +                      continue;
 +              }
 +
 +              if (line[0] == 'o' && line[1] == 'k')
 +                      hint->status = REF_STATUS_OK;
 +              else {
 +                      hint->status = REF_STATUS_REMOTE_REJECT;
 +                      ret = -1;
 +              }
 +              if (msg)
 +                      hint->remote_status = xstrdup(msg);
 +              /* start our next search from the next ref */
 +              hint = hint->next;
 +      }
 +      return ret;
 +}
 +
 +static void print_helper_status(struct ref *ref)
 +{
 +      struct strbuf buf = STRBUF_INIT;
 +
 +      for (; ref; ref = ref->next) {
 +              const char *msg = NULL;
 +              const char *res;
 +
 +              switch(ref->status) {
 +              case REF_STATUS_NONE:
 +                      res = "error";
 +                      msg = "no match";
 +                      break;
 +
 +              case REF_STATUS_OK:
 +                      res = "ok";
 +                      break;
 +
 +              case REF_STATUS_UPTODATE:
 +                      res = "ok";
 +                      msg = "up to date";
 +                      break;
 +
 +              case REF_STATUS_REJECT_NONFASTFORWARD:
 +                      res = "error";
 +                      msg = "non-fast forward";
 +                      break;
 +
 +              case REF_STATUS_REJECT_NODELETE:
 +              case REF_STATUS_REMOTE_REJECT:
 +                      res = "error";
 +                      break;
 +
 +              case REF_STATUS_EXPECTING_REPORT:
 +              default:
 +                      continue;
 +              }
 +
 +              strbuf_reset(&buf);
 +              strbuf_addf(&buf, "%s %s", res, ref->name);
 +              if (ref->remote_status)
 +                      msg = ref->remote_status;
 +              if (msg) {
 +                      strbuf_addch(&buf, ' ');
 +                      quote_two_c_style(&buf, "", msg, 0);
 +              }
 +              strbuf_addch(&buf, '\n');
 +
 +              safe_write(1, buf.buf, buf.len);
 +      }
 +      strbuf_release(&buf);
 +}
 +
 +static int sideband_demux(int in, int out, void *data)
 +{
 +      int *fd = data;
++#ifdef NO_PTHREADS
++      close(fd[1]);
++#endif
 +      int ret = recv_sideband("send-pack", fd[0], out);
 +      close(out);
 +      return ret;
 +}
 +
 +int send_pack(struct send_pack_args *args,
 +            int fd[], struct child_process *conn,
 +            struct ref *remote_refs,
 +            struct extra_have_objects *extra_have)
 +{
 +      int in = fd[0];
 +      int out = fd[1];
 +      struct strbuf req_buf = STRBUF_INIT;
 +      struct ref *ref;
 +      int new_refs;
 +      int allow_deleting_refs = 0;
 +      int status_report = 0;
 +      int use_sideband = 0;
 +      unsigned cmds_sent = 0;
 +      int ret;
 +      struct async demux;
 +
 +      /* Does the other end support the reporting? */
 +      if (server_supports("report-status"))
 +              status_report = 1;
 +      if (server_supports("delete-refs"))
 +              allow_deleting_refs = 1;
 +      if (server_supports("ofs-delta"))
 +              args->use_ofs_delta = 1;
 +      if (server_supports("side-band-64k"))
 +              use_sideband = 1;
 +
 +      if (!remote_refs) {
 +              fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 +                      "Perhaps you should specify a branch such as 'master'.\n");
 +              return 0;
 +      }
 +
 +      /*
 +       * Finally, tell the other end!
 +       */
 +      new_refs = 0;
 +      for (ref = remote_refs; ref; ref = ref->next) {
 +              if (!ref->peer_ref && !args->send_mirror)
 +                      continue;
 +
 +              /* Check for statuses set by set_ref_status_for_push() */
 +              switch (ref->status) {
 +              case REF_STATUS_REJECT_NONFASTFORWARD:
 +              case REF_STATUS_UPTODATE:
 +                      continue;
 +              default:
 +                      ; /* do nothing */
 +              }
 +
 +              if (ref->deletion && !allow_deleting_refs) {
 +                      ref->status = REF_STATUS_REJECT_NODELETE;
 +                      continue;
 +              }
 +
 +              if (!ref->deletion)
 +                      new_refs++;
 +
 +              if (args->dry_run) {
 +                      ref->status = REF_STATUS_OK;
 +              } else {
 +                      char *old_hex = sha1_to_hex(ref->old_sha1);
 +                      char *new_hex = sha1_to_hex(ref->new_sha1);
 +
 +                      if (!cmds_sent && (status_report || use_sideband)) {
 +                              packet_buf_write(&req_buf, "%s %s %s%c%s%s",
 +                                      old_hex, new_hex, ref->name, 0,
 +                                      status_report ? " report-status" : "",
 +                                      use_sideband ? " side-band-64k" : "");
 +                      }
 +                      else
 +                              packet_buf_write(&req_buf, "%s %s %s",
 +                                      old_hex, new_hex, ref->name);
 +                      ref->status = status_report ?
 +                              REF_STATUS_EXPECTING_REPORT :
 +                              REF_STATUS_OK;
 +                      cmds_sent++;
 +              }
 +      }
 +
 +      if (args->stateless_rpc) {
 +              if (!args->dry_run && cmds_sent) {
 +                      packet_buf_flush(&req_buf);
 +                      send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
 +              }
 +      } else {
 +              safe_write(out, req_buf.buf, req_buf.len);
 +              packet_flush(out);
 +      }
 +      strbuf_release(&req_buf);
 +
 +      if (use_sideband && cmds_sent) {
 +              memset(&demux, 0, sizeof(demux));
 +              demux.proc = sideband_demux;
 +              demux.data = fd;
 +              demux.out = -1;
 +              if (start_async(&demux))
 +                      die("receive-pack: unable to fork off sideband demultiplexer");
 +              in = demux.out;
 +      }
 +
 +      if (new_refs && cmds_sent) {
 +              if (pack_objects(out, remote_refs, extra_have, args) < 0) {
 +                      for (ref = remote_refs; ref; ref = ref->next)
 +                              ref->status = REF_STATUS_NONE;
++                      if (args->stateless_rpc)
++                              close(out);
 +                      if (use_sideband)
 +                              finish_async(&demux);
 +                      return -1;
 +              }
 +      }
 +      if (args->stateless_rpc && cmds_sent)
 +              packet_flush(out);
 +
 +      if (status_report && cmds_sent)
 +              ret = receive_status(in, remote_refs);
 +      else
 +              ret = 0;
 +      if (args->stateless_rpc)
 +              packet_flush(out);
 +
 +      if (use_sideband && cmds_sent) {
 +              if (finish_async(&demux)) {
 +                      error("error in sideband demultiplexer");
 +                      ret = -1;
 +              }
 +              close(demux.out);
 +      }
 +
 +      if (ret < 0)
 +              return ret;
 +
 +      if (args->porcelain)
 +              return 0;
 +
 +      for (ref = remote_refs; ref; ref = ref->next) {
 +              switch (ref->status) {
 +              case REF_STATUS_NONE:
 +              case REF_STATUS_UPTODATE:
 +              case REF_STATUS_OK:
 +                      break;
 +              default:
 +                      return -1;
 +              }
 +      }
 +      return 0;
 +}
 +
 +int cmd_send_pack(int argc, const char **argv, const char *prefix)
 +{
 +      int i, nr_refspecs = 0;
 +      const char **refspecs = NULL;
 +      const char *remote_name = NULL;
 +      struct remote *remote = NULL;
 +      const char *dest = NULL;
 +      int fd[2];
 +      struct child_process *conn;
 +      struct extra_have_objects extra_have;
 +      struct ref *remote_refs, *local_refs;
 +      int ret;
 +      int helper_status = 0;
 +      int send_all = 0;
 +      const char *receivepack = "git-receive-pack";
 +      int flags;
 +      int nonfastforward = 0;
 +
 +      argv++;
 +      for (i = 1; i < argc; i++, argv++) {
 +              const char *arg = *argv;
 +
 +              if (*arg == '-') {
 +                      if (!prefixcmp(arg, "--receive-pack=")) {
 +                              receivepack = arg + 15;
 +                              continue;
 +                      }
 +                      if (!prefixcmp(arg, "--exec=")) {
 +                              receivepack = arg + 7;
 +                              continue;
 +                      }
 +                      if (!prefixcmp(arg, "--remote=")) {
 +                              remote_name = arg + 9;
 +                              continue;
 +                      }
 +                      if (!strcmp(arg, "--all")) {
 +                              send_all = 1;
 +                              continue;
 +                      }
 +                      if (!strcmp(arg, "--dry-run")) {
 +                              args.dry_run = 1;
 +                              continue;
 +                      }
 +                      if (!strcmp(arg, "--mirror")) {
 +                              args.send_mirror = 1;
 +                              continue;
 +                      }
 +                      if (!strcmp(arg, "--force")) {
 +                              args.force_update = 1;
 +                              continue;
 +                      }
 +                      if (!strcmp(arg, "--verbose")) {
 +                              args.verbose = 1;
 +                              continue;
 +                      }
 +                      if (!strcmp(arg, "--thin")) {
 +                              args.use_thin_pack = 1;
 +                              continue;
 +                      }
 +                      if (!strcmp(arg, "--stateless-rpc")) {
 +                              args.stateless_rpc = 1;
 +                              continue;
 +                      }
 +                      if (!strcmp(arg, "--helper-status")) {
 +                              helper_status = 1;
 +                              continue;
 +                      }
 +                      usage(send_pack_usage);
 +              }
 +              if (!dest) {
 +                      dest = arg;
 +                      continue;
 +              }
 +              refspecs = (const char **) argv;
 +              nr_refspecs = argc - i;
 +              break;
 +      }
 +      if (!dest)
 +              usage(send_pack_usage);
 +      /*
 +       * --all and --mirror are incompatible; neither makes sense
 +       * with any refspecs.
 +       */
 +      if ((refspecs && (send_all || args.send_mirror)) ||
 +          (send_all && args.send_mirror))
 +              usage(send_pack_usage);
 +
 +      if (remote_name) {
 +              remote = remote_get(remote_name);
 +              if (!remote_has_url(remote, dest)) {
 +                      die("Destination %s is not a uri for %s",
 +                          dest, remote_name);
 +              }
 +      }
 +
 +      if (args.stateless_rpc) {
 +              conn = NULL;
 +              fd[0] = 0;
 +              fd[1] = 1;
 +      } else {
 +              conn = git_connect(fd, dest, receivepack,
 +                      args.verbose ? CONNECT_VERBOSE : 0);
 +      }
 +
 +      memset(&extra_have, 0, sizeof(extra_have));
 +
 +      get_remote_heads(fd[0], &remote_refs, 0, NULL, REF_NORMAL,
 +                       &extra_have);
 +
 +      transport_verify_remote_names(nr_refspecs, refspecs);
 +
 +      local_refs = get_local_heads();
 +
 +      flags = MATCH_REFS_NONE;
 +
 +      if (send_all)
 +              flags |= MATCH_REFS_ALL;
 +      if (args.send_mirror)
 +              flags |= MATCH_REFS_MIRROR;
 +
 +      /* match them up */
 +      if (match_refs(local_refs, &remote_refs, nr_refspecs, refspecs, flags))
 +              return -1;
 +
 +      set_ref_status_for_push(remote_refs, args.send_mirror,
 +              args.force_update);
 +
 +      ret = send_pack(&args, fd, conn, remote_refs, &extra_have);
 +
 +      if (helper_status)
 +              print_helper_status(remote_refs);
 +
 +      close(fd[1]);
 +      close(fd[0]);
 +
 +      ret |= finish_connect(conn);
 +
 +      if (!helper_status)
 +              transport_print_push_status(dest, remote_refs, args.verbose, 0, &nonfastforward);
 +
 +      if (!args.dry_run && remote) {
 +              struct ref *ref;
 +              for (ref = remote_refs; ref; ref = ref->next)
 +                      transport_update_tracking_ref(remote, ref, args.verbose);
 +      }
 +
 +      if (!ret && !transport_refs_pushed(remote_refs))
 +              fprintf(stderr, "Everything up-to-date\n");
 +
 +      return ret;
 +}