}
  if( find_option("no-http-compression",0,0)!=0 ){
    *pSyncFlags |= SYNC_NOHTTPCOMPRESS;
  }
  if( find_option("all",0,0)!=0 ){
    *pSyncFlags |= SYNC_ALLURL;
  }
  if( ((*pSyncFlags) & SYNC_PULL)!=0
   && find_option("share-links",0,0)!=0
  ){
    *pSyncFlags |= SYNC_SHARE_LINKS;
  }
  url_proxy_options();
  clone_ssh_find_options();
  if( !uvOnly ) db_find_and_open_repository(0, 0);
  db_open_config(0, 1);
  if( g.argc==2 ){
    if( db_get_boolean("auto-shun",0) ) configSync = CONFIGSET_SHUN;
  }else if( g.argc==3 ){

**   --ipv4                     Use only IPv4, not IPv6
**   --no-http-compression      Do not compress HTTP traffic
**   --once                     Do not remember URL for subsequent syncs
**   --private                  Pull private branches too
**   --project-code CODE        Use CODE as the project code
**   --proxy PROXY              Use the specified HTTP proxy
**   -R|--repository REPO       Local repository to pull into
**   --share-links              Share links to mirror repos
**   --ssl-identity FILE        Local SSL credentials, if requested by remote
**   --ssh-command SSH          Use SSH as the "ssh" command
**   -v|--verbose               Additional (debugging) output
**   --verily                   Exchange extra information with the remote
**                              to ensure no content is overlooked
**
** See also: [[clone]], [[config]], [[push]], [[remote]], [[sync]]

**                              if required by the remote website
**   --ipv4                     Use only IPv4, not IPv6
**   --no-http-compression      Do not compress HTTP traffic
**   --once                     Do not remember URL for subsequent syncs
**   --proxy PROXY              Use the specified HTTP proxy
**   --private                  Sync private branches too
**   -R|--repository REPO       Local repository to sync with
**   --share-links              Share links to mirror repos
**   --ssl-identity FILE        Local SSL credentials, if requested by remote
**   --ssh-command SSH          Use SSH as the "ssh" command
**   -u|--unversioned           Also sync unversioned content
**   -v|--verbose               Additional (debugging) output
**   --verily                   Exchange extra information with the remote
**                              to ensure no content is overlooked
**

  int rc;
  const char *zScript = 0;
  char *zUuidList = 0;
  int nUuidList = 0;
  char **pzUuidList = 0;
  int *pnUuidList = 0;
  int uvCatalogSent = 0;
  int bSendLinks = 0;

  if( fossil_strcmp(PD("REQUEST_METHOD","POST"),"POST") ){
     fossil_redirect_home();
  }
  g.zLogin = "anonymous";
  login_set_anon_nobody_capabilities();
  login_check_credentials();

      if( blob_eq(&xfer.aToken[1], "send-private") ){
        login_check_credentials();
        if( !g.perm.Private ){
          server_private_xfer_not_authorized();
        }else{
          xfer.syncPrivate = 1;
        }
      }else

      /*   pragma send-catalog
      **
      ** The client wants to see igot cards for all known artifacts.
      ** This is used as part of "sync --verily" to help ensure that
      ** no artifacts have been missed on prior syncs.
      */
      if( blob_eq(&xfer.aToken[1], "send-catalog") ){
        xfer.resync = 0x7fffffff;
      }else

      /*   pragma client-version VERSION ?DATE? ?TIME?
      **
      ** The client announces to the server what version of Fossil it
      ** is running.  The DATE and TIME are a pure numeric ISO8601 time
      ** for the specific check-in of the client.
      */
      if( xfer.nToken>=3 && blob_eq(&xfer.aToken[1], "client-version") ){
        xfer.remoteVersion = atoi(blob_str(&xfer.aToken[2]));
        if( xfer.nToken>=5 ){
          xfer.remoteDate = atoi(blob_str(&xfer.aToken[3]));
          xfer.remoteTime = atoi(blob_str(&xfer.aToken[4]));
          @ pragma server-version %d(RELEASE_VERSION_NUMBER) \
          @ %d(MANIFEST_NUMERIC_DATE) %d(MANIFEST_NUMERIC_TIME)
        }
      }else

      /*   pragma uv-hash HASH
      **
      ** The client wants to make sure that unversioned files are all synced.
      ** If the HASH does not match, send a complete catalog of
      ** "uvigot" cards.
      */

            @ pragma uv-push-ok
          }else if( g.perm.Read ){
            @ pragma uv-pull-only
          }
          send_unversioned_catalog(&xfer);
        }
        uvCatalogSent = 1;
      }else

      /*   pragma ci-lock CHECKIN-HASH CLIENT-ID
      **
      ** The client wants to make non-branch commit against the check-in
      ** identified by CHECKIN-HASH.  The server will remember this and
      ** subsequent ci-lock requests from different clients will generate
      ** a ci-lock-fail pragma in the reply.

            blob_str(&xfer.aToken[3])
          );
          db_protect_pop();
        }
        if( db_get_boolean("forbid-delta-manifests",0) ){
          @ pragma avoid-delta-manifests
        }
      }else

      /*   pragma ci-unlock CLIENT-ID
      **
      ** Remove any locks previously held by CLIENT-ID.  Clients send this
      ** pragma with their own ID whenever they know that they no longer
      ** have any commits pending.
      */
      if( blob_eq(&xfer.aToken[1], "ci-unlock")
       && xfer.nToken==3
       && blob_is_hname(&xfer.aToken[2])
      ){
        db_unprotect(PROTECT_CONFIG);
        db_multi_exec(
          "DELETE FROM config"
          " WHERE name GLOB 'ci-lock-*'"
          "   AND json_extract(value,'$.clientid')=%Q",
          blob_str(&xfer.aToken[2])
        );
        db_protect_pop();
      }else

      /*   pragma client-url URL
      **
      ** This pragma is an informational notification to the server that
      ** their relationship could, in theory, be inverted by having the
      ** server call the client at URL.
      */
      if( blob_eq(&xfer.aToken[1], "client-url")
       && xfer.nToken==3
       && g.perm.Write
      ){
        xfer_syncwith(blob_str(&xfer.aToken[2]), 1);
      }else

      /*    pragma req-links
      **
      ** The client sends this message to the server to ask the server
      ** to tell it about alternative repositories  in the reply.
      */
      if( blob_eq(&xfer.aToken[1], "req-links") ){
        bSendLinks = 1;
      }

    }else

    /* Unknown message
    */
    {

    create_cluster();
    send_unclustered(&xfer);
    if( xfer.syncPrivate ) send_private(&xfer);
  }
  hook_expecting_more_artifacts(xfer.nGimmeSent?60:0);
  db_multi_exec("DROP TABLE onremote; DROP TABLE unk;");
  manifest_crosslink_end(MC_PERMIT_HOOKS);

  /* Send URLs for alternative repositories for the same project,
  ** if requested by the client. */
  if( bSendLinks && g.zBaseURL ){
    Stmt q;
    db_prepare(&q,
      "WITH remote(mtime, url, arg) AS (\n"
      "  SELECT mtime, substr(name,10), '{}' FROM config\n"
      "   WHERE name GLOB 'syncwith:http*'\n"
      "  UNION ALL\n"
      "  SELECT mtime, substr(name,10), '{}' FROM config\n"
      "   WHERE name GLOB 'syncfrom:http*'\n"
      "  UNION ALL\n"
      "  SELECT mtime, substr(name,9), '{\"type\":\"git\"}' FROM config\n"
      "   WHERE name GLOB 'gitpush:*'\n"
      ")\n"
      "SELECT url, json_insert(arg,'$.src',%Q), max(mtime)\n"
      "  FROM remote WHERE mtime>unixepoch('now','-1 month')\n"
      " GROUP BY url;",
      g.zBaseURL
    );
    while( db_step(&q)==SQLITE_ROW ){
      UrlData x;
      const char *zUrl = db_column_text(&q, 0);
      const char *zArg = db_column_text(&q, 1);
      i64 iMtime = db_column_int64(&q, 2);
      memset(&x, 0, sizeof(x));
      url_parse_local(zUrl, URL_OMIT_USER, &x);
      if( x.name!=0 && sqlite3_strlike("%localhost%", x.name, 0)!=0 ){
        @ pragma link %F(x.canonical) %F(zArg) %lld(iMtime)
      }
      url_unparse(&x);      
    }
    db_finalize(&q);
  }

  /* Send the server timestamp last, in case prior processing happened
  ** to use up a significant fraction of our time window.
  */
  zNow = db_text(0, "SELECT strftime('%%Y-%%m-%%dT%%H:%%M:%%S', 'now')");
  @ # timestamp %s(zNow)
  free(zNow);

static const char zBriefFormat[] =
   "Round-trips: %d   Artifacts sent: %d  received: %d\r";

#if INTERFACE
/*
** Flag options for controlling client_sync()
*/
#define SYNC_PUSH           0x00001    /* push content client to server */
#define SYNC_PULL           0x00002    /* pull content server to client */
#define SYNC_CLONE          0x00004    /* clone the repository */
#define SYNC_PRIVATE        0x00008    /* Also transfer private content */
#define SYNC_VERBOSE        0x00010    /* Extra diagnostics */
#define SYNC_RESYNC         0x00020    /* --verily */
#define SYNC_FROMPARENT     0x00040    /* Pull from the parent project */
#define SYNC_UNVERSIONED    0x00100    /* Sync unversioned content */
#define SYNC_UV_REVERT      0x00200    /* Copy server unversioned to client */
#define SYNC_UV_TRACE       0x00400    /* Describe UV activities */
#define SYNC_UV_DRYRUN      0x00800    /* Do not actually exchange files */
#define SYNC_IFABLE         0x01000    /* Inability to sync is not fatal */
#define SYNC_CKIN_LOCK      0x02000    /* Lock the current check-in */
#define SYNC_NOHTTPCOMPRESS 0x04000    /* Do not compression HTTP messages */
#define SYNC_ALLURL         0x08000    /* The --all flag - sync to all URLs */
#define SYNC_SHARE_LINKS    0x10000    /* Request alternate repo links */
#endif

/*
** Floating-point absolute value
*/
static double fossil_fabs(double x){
  return x>0.0 ? x : -x;

  if( zAltPCode==0 ){
    const char *zSelfUrl = public_url();
    if( zSelfUrl ){
      blob_appendf(&send, "pragma client-url %s\n", zSelfUrl);
    }
  }

  /* Request URLs of alternative repositories
  */
  if( zAltPCode==0 && (syncFlags & SYNC_SHARE_LINKS)!=0 ){
    blob_appendf(&send, "pragma req-links\n");
  }

  while( go ){
    int newPhantom = 0;
    char *zRandomness;
    db_begin_transaction();
    db_record_repository_filename(0);

        **
        ** If the server is unwill to accept new unversioned content (because
        ** this client lacks the necessary permissions) then it sends a
        ** "uv-pull-only" pragma so that the client will know not to waste
        ** bandwidth trying to upload unversioned content.  If the server
        ** does accept new unversioned content, it sends "uv-push-ok".
        */
        else if( syncFlags & SYNC_UNVERSIONED ){
          if( blob_eq(&xfer.aToken[1], "uv-pull-only") ){
            uvPullOnly = 1;
            if( syncFlags & SYNC_UV_REVERT ) uvDoPush = 1;
          }else if( blob_eq(&xfer.aToken[1], "uv-push-ok") ){
            uvDoPush = 1;
          }
        }

        **
        ** Discourage the use of delta manifests.  The remote side sends
        ** this pragma when its forbid-delta-manifests setting is true.
        */
        else if( blob_eq(&xfer.aToken[1], "avoid-delta-manifests") ){
          g.bAvoidDeltaManifests = 1;
        }

        /*    pragma link URL ARG MTIME
        **
        ** The server has sent the URL for a link to another repository.
        ** Record this as a link:URL entry in the config table.
        */
        else if( blob_eq(&xfer.aToken[1], "link")
              && xfer.nToken==5
              && (syncFlags & SYNC_SHARE_LINKS)!=0
        ){
          UrlData x;
          char *zUrl = blob_str(&xfer.aToken[2]);
          char *zArg = blob_str(&xfer.aToken[3]);
          i64 iTime = strtoll(blob_str(&xfer.aToken[4]),0,0);
          memset(&x, 0, sizeof(x));
          defossilize(zUrl);
          defossilize(zArg);
          url_parse_local(zUrl, URL_OMIT_USER, &x);
          if( x.protocol
           && strncmp(x.protocol,"http",4)==0
           && iTime>0
          ){
            db_unprotect(PROTECT_CONFIG);
            db_multi_exec(
              "INSERT INTO config(name,value,mtime)\n"
              " VALUES('link:%q',%Q,%lld)\n"
              " ON CONFLICT DO UPDATE\n"
              "   SET value=excluded.value, mtime=excluded.mtime\n"
              "   WHERE mtime<excluded.mtime;",
              zUrl, zArg, iTime
            );
            db_protect_pop();
          }
          url_unparse(&x);
        }

      }else

      /*   error MESSAGE
      **
      ** The server is reporting an error.  The client will abandon
      ** the sync session.
      **