/* ------------------------------------------------------------ */
/*
HTTrack Website Copier, Offline Browser for Windows and Unix
Copyright (C) 1998 Xavier Roche and other contributors

SPDX-License-Identifier: GPL-3.0-or-later

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.

Ethical use: we kindly ask that you NOT use this software to harvest email
addresses or to collect any other private information about people. Doing so
would dishonor our work and waste the many hours we have spent on it.

Please visit our Website: http://www.httrack.com
*/

/* ------------------------------------------------------------ */
/* File: basic FTP protocol manager                             */
/* Author: Xavier Roche                                         */
/* ------------------------------------------------------------ */

/* Internal engine bytecode */
#define HTS_INTERNAL_BYTECODE

// Gestion protocole ftp
// Version .05 (01/2000)

#include "htsftp.h"

#include "htscore.h"
#include "htsthread.h"
#ifdef _WIN32
#else
//inet_ntoa
#include <arpa/inet.h>
#endif

#ifdef _WIN32
#ifndef __cplusplus
// DOS
#include <process.h>            /* _beginthread, _endthread */
#endif
#endif

// ftp mode passif
#define FTP_PASV 1

#define FTP_DEBUG 0

#if USE_BEGINTHREAD

void back_launch_ftp(void *pP) {
  FTPDownloadStruct *pStruct = (FTPDownloadStruct *) pP;

  if (pStruct == NULL)
    return;

  if (pStruct == NULL) {
#if FTP_DEBUG
    printf("[ftp error: no args]\n");
#endif
    return;
  }

  /* Initialize */
  hts_init();

  // lancer ftp
#if FTP_DEBUG
  printf("[Launching main ftp routine]\n");
#endif
  run_launch_ftp(pStruct);
  // prêt
  pStruct->pBack->status = STATUS_FTP_READY;

  /* Delete structure */
  free(pP);

  /* Uninitialize */
  hts_uninit();
  return;
}

// lancer en back
void launch_ftp(FTPDownloadStruct * params) {
  // DOS
#if FTP_DEBUG
  printf("[Launching main ftp thread]\n");
#endif
  hts_newthread(back_launch_ftp, (void *) params);
}

#else
#error No more supported
#endif

// pour l'arrêt du ftp
#ifdef _WIN32
#define _T_SOC_close(soc)  do { closesocket(soc); soc=INVALID_SOCKET; } while(0)
#else
#define _T_SOC_close(soc)  do { close(soc); soc=INVALID_SOCKET; } while(0)
#endif
#define _HALT_FTP { \
  if ( soc_ctl     != INVALID_SOCKET ) _T_SOC_close(soc_ctl); \
  if ( soc_servdat != INVALID_SOCKET ) _T_SOC_close(soc_servdat); \
  if ( soc_dat     != INVALID_SOCKET ) _T_SOC_close(soc_dat); \
}
#define _CHECK_HALT_FTP \
  if (stop_ftp(back)) { \
  _HALT_FTP \
  return 0; \
  }

/* Bounded split of a hostile-URL "user[:pass]@" prefix (see htsftp.h). */
void ftp_split_userpass(const char *src, const char *end, char *user,
                        size_t user_size, char *pass, size_t pass_size) {
  size_t n = 0;

  assertf(user_size > 0 && pass_size > 0); /* the size-1 math underflows on 0 */

  while (src[n] != '\0' && src[n] != ':') {
    if (n < user_size - 1)
      user[n] = src[n];
    n++;
  }
  user[n < user_size ? n : user_size - 1] = '\0';
  pass[0] = '\0';
  if (src[n] == ':') { // password follows the colon
    const size_t base = n + 1;
    size_t k = 0;

    while (&src[base + k + 1] < end && src[base + k] != '\0') {
      if (k < pass_size - 1)
        pass[k] = src[base + k];
      k++;
    }
    pass[k < pass_size ? k : pass_size - 1] = '\0';
  }
}

// la véritable fonction une fois lancées les routines thread/fork
int run_launch_ftp(FTPDownloadStruct * pStruct) {
  lien_back *back = pStruct->pBack;
  httrackp *opt = pStruct->pOpt;
  char user[256] = "anonymous";
  char pass[256] = "user@";
  char line_retr[2048];
  int port = 21;

#if FTP_PASV
  int port_pasv = 0;
#endif
  char BIGSTK adr_ip[1024];
  char *adr, *real_adr;
  const char *ftp_filename = "";
  int timeout = 300;            // timeout
  int timeout_onfly = 8;        // attente réponse supplémentaire
  int transfer_list = 0;        // directory
  int rest_understood = 0;      // rest command understood

  //
  T_SOC soc_ctl = INVALID_SOCKET;
  T_SOC soc_servdat = INVALID_SOCKET;
  T_SOC soc_dat = INVALID_SOCKET;
  SOCaddr server_data;

  //
  line_retr[0] = adr_ip[0] = '\0';

  timeout = 300;

  // effacer
  strcpybuff(back->r.msg, "");
  back->r.statuscode = 0;
  back->r.size = 0;

  // récupérer user et pass si présents, et sauter user:id@ dans adr
  real_adr = strchr(back->url_adr, ':');
  if (real_adr)
    real_adr++;
  else
    real_adr = back->url_adr;
  while(*real_adr == '/')
    real_adr++;                 // sauter /
  if ((adr = jump_identification(real_adr)) != real_adr) {      // user
    ftp_split_userpass(real_adr, adr, user, sizeof(user), pass, sizeof(pass));
  }
  // Calculer RETR <nom>
  {
    char *a;

    a = back->url_fil;
    if (a != NULL && *a != '\0') {
      ftp_filename = a;
      if (strnotempty(a)) {
        char catbuff[CATBUFF_SIZE];
        char *ua = unescape_http(catbuff, sizeof(catbuff), a);
        int len_a = (int) strlen(ua);

        if (len_a > 0 && ua[len_a - 1] == '/') {        /* obviously a directory listing */
          transfer_list = 1;
          snprintf(line_retr, sizeof(line_retr), "LIST -A %s", ua);
        } else if ((strchr(ua, ' '))
                   || (strchr(ua, '\"'))
                   || (strchr(ua, '\''))
          ) {
          snprintf(line_retr, sizeof(line_retr), "RETR \"%s\"", ua);
        } else {                /* Regular one */
          snprintf(line_retr, sizeof(line_retr), "RETR %s", ua);
        }
      } else {
        transfer_list = 1;
        snprintf(line_retr, sizeof(line_retr), "LIST -A");
      }
    } else {
      strcpybuff(back->r.msg, "Unexpected PORT error");
      back->r.statuscode = STATUSCODE_INVALID;
    }
  }

#if FTP_DEBUG
  printf("Connecting to %s...\n", adr);
#endif

  // connexion
  {
    SOCaddr server;
    char *a;
    char _adr[256];
    const char *error = "unknown error";

    _adr[0] = '\0';
    //T_SOC soc_ctl;
    // effacer structure
    memset(&server, 0, sizeof(server));

    // port
    a = strchr(adr, ':');       // port
    if (a) {
      sscanf(a + 1, "%d", &port);
      strncatbuff(_adr, adr, (int) (a - adr));
    } else
      strcpybuff(_adr, adr);

    // récupérer adresse résolue
    strcpybuff(back->info, "host name");
    if (hts_dns_resolve2(opt, _adr, &server, &error) == NULL) {
      snprintf(back->r.msg, sizeof(back->r.msg),
               "Unable to get server's address: %s", error);
      back->r.statuscode = STATUSCODE_NON_FATAL;
      _HALT_FTP return 0;
    }
    _CHECK_HALT_FTP;

    // copie adresse pour cnx data
    SOCaddr_copy_SOCaddr(server_data, server);

    // créer ("attachement") une socket (point d'accès) internet,en flot
    soc_ctl = (T_SOC) socket(SOCaddr_sinfamily(server), SOCK_STREAM, 0);
    if (soc_ctl == INVALID_SOCKET) {
      strcpybuff(back->r.msg, "Unable to create a socket");
      back->r.statuscode = STATUSCODE_INVALID;
      _HALT_FTP return 0;
    }

    SOCaddr_initport(server, port);

    // connexion (bloquante, on est en thread)
    strcpybuff(back->info, "connect");

    if (connect(soc_ctl, &SOCaddr_sockaddr(server), SOCaddr_size(server)) != 0) {
      strcpybuff(back->r.msg, "Unable to connect to the server");
      back->r.statuscode = STATUSCODE_INVALID;
      _HALT_FTP return 0;
#ifdef _WIN32
    }
#else
    }
#endif
    _CHECK_HALT_FTP;

    {
      char BIGSTK line[1024];

      // envoi du login

      // --USER--
      get_ftp_line(soc_ctl, line, sizeof(line), timeout);     // en tête
      _CHECK_HALT_FTP;

      if (line[0] == '2') {     // ok, connecté
        strcpybuff(back->info, "login: user");
        snprintf(line, sizeof(line), "USER %s", user);
        send_line(soc_ctl, line);
        get_ftp_line(soc_ctl, line, sizeof(line), timeout);
        _CHECK_HALT_FTP;
        if ((line[0] == '3') || (line[0] == '2')) {
          // --PASS--
          if (line[0] == '3') {
            strcpybuff(back->info, "login: pass");
            snprintf(line, sizeof(line), "PASS %s", pass);
            send_line(soc_ctl, line);
            get_ftp_line(soc_ctl, line, sizeof(line), timeout);
            _CHECK_HALT_FTP;
          }
          if (line[0] == '2') { // ok
            send_line(soc_ctl, "TYPE I");
            get_ftp_line(soc_ctl, line, sizeof(line), timeout);
            _CHECK_HALT_FTP;
            if (line[0] == '2') {
              // ok
            } else {
              strcpybuff(back->r.msg, "TYPE I error");
              back->r.statuscode = STATUSCODE_INVALID;
            }

          } else {
            snprintf(back->r.msg, sizeof(back->r.msg), "Bad password: %s",
                     linejmp(line));
            back->r.statuscode = STATUSCODE_INVALID;
          }
        } else {
          snprintf(back->r.msg, sizeof(back->r.msg), "Bad user name: %s",
                   linejmp(line));
          back->r.statuscode = STATUSCODE_INVALID;
        }
      } else {
        snprintf(back->r.msg, sizeof(back->r.msg), "Connection refused: %s",
                 linejmp(line));
        back->r.statuscode = STATUSCODE_INVALID;
      }

      // ok, si on est prêts on écoute sur un port et on demande la sauce
      if (back->r.statuscode != -1) {

        //
        // Pré-REST
        //
#if FTP_PASV
        if (SOCaddr_getproto(server) == '1') {
          strcpybuff(back->info, "pasv");
          snprintf(line, sizeof(line), "PASV");
          send_line(soc_ctl, line);
          get_ftp_line(soc_ctl, line, sizeof(line), timeout);
        } else {                /* ipv6 */
          line[0] = '\0';
        }
        _CHECK_HALT_FTP;
        if (line[0] == '2') {
          char *a, *b, *c;

          a = strchr(line, '(');        // exemple: 227 Entering Passive Mode (123,45,67,89,177,27)
          if (a) {

            // -- analyse de l'adresse IP et du port --
            a++;
            b = strchr(a, ',');
            if (b)
              b = strchr(b + 1, ',');
            if (b)
              b = strchr(b + 1, ',');
            if (b)
              b = strchr(b + 1, ',');
            c = a;
            while((c = strchr(c, ',')))
              *c = '.';         // remplacer , par .
            if (b)
              *b = '\0';
            //
            strcpybuff(adr_ip, a);      // copier adresse ip
            //
            if (b) {
              a = b + 1;        // début du port
              b = strchr(a, '.');
              if (b) {
                int n1, n2;

                //
                *b = '\0';
                b++;
                c = strchr(b, ')');
                if (c) {
                  *c = '\0';
                  if ((sscanf(a, "%d", &n1) == 1) && (sscanf(b, "%d", &n2) == 1)
                      && (strlen(adr_ip) <= 16)) {
                    port_pasv = n2 + (n1 << 8);
                  }
                } else {
                  deletesoc(soc_dat);
                  soc_dat = INVALID_SOCKET;
                }               // sinon on est prêts
              }
            }
            // -- fin analyse de l'adresse IP et du port --
          } else {
            snprintf(back->r.msg, sizeof(back->r.msg), "PASV incorrect: %s",
                     linejmp(line));
            back->r.statuscode = STATUSCODE_INVALID;
          }                     // sinon on est prêts
        } else {
          /*
           * try epsv (ipv6) *
           */
          strcpybuff(back->info, "pasv");
          snprintf(line, sizeof(line), "EPSV");
          send_line(soc_ctl, line);
          get_ftp_line(soc_ctl, line, sizeof(line), timeout);
          _CHECK_HALT_FTP;
          if (line[0] == '2') { /* got it */
            char *a;

            a = strchr(line, '(');      // exemple: 229 Entering Extended Passive Mode (|||6446|)
            if ((a != NULL)
                && (*a == '(')
                && (*(a + 1))
                && (*(a + 1) == *(a + 2)) && (*(a + 1) == *(a + 3))
                && (isdigit(*(a + 4)))
                && (*(a + 5))
              ) {
              unsigned int n1 = 0;

              if (sscanf(a + 4, "%d", &n1) == 1) {
                if ((n1 < 65535) && (n1 > 0)) {
                  port_pasv = n1;
                }
              }
            } else {
              snprintf(back->r.msg, sizeof(back->r.msg), "EPSV incorrect: %s",
                       linejmp(line));
              back->r.statuscode = STATUSCODE_INVALID;
            }
          } else {
            snprintf(back->r.msg, sizeof(back->r.msg), "PASV/EPSV error: %s",
                     linejmp(line));
            back->r.statuscode = STATUSCODE_INVALID;
          }                     // sinon on est prêts
        }
#else
        // rien à faire avant
#endif

#if FTP_PASV
        if (port_pasv) {
#endif
          // SIZE
          if (back->r.statuscode != -1) {
            if (!transfer_list) {
              char catbuff[CATBUFF_SIZE];
              char *ua = unescape_http(catbuff, sizeof(catbuff), ftp_filename);

              if ((strchr(ua, ' '))
                  || (strchr(ua, '\"'))
                  || (strchr(ua, '\''))
                ) {
                snprintf(line, sizeof(line), "SIZE \"%s\"", ua);
              } else {
                snprintf(line, sizeof(line), "SIZE %s", ua);
              }

              // SIZE?
              strcpybuff(back->info, "size");
              send_line(soc_ctl, line);
              get_ftp_line(soc_ctl, line, sizeof(line), timeout);
              _CHECK_HALT_FTP;
              if (line[0] == '2') {     // SIZE compris, ALORS tester REST (sinon pas tester: cf probleme des txt.gz decompresses a la volee)
                char *szstr = strchr(line, ' ');

                if (szstr) {
                  LLint size = 0;

                  szstr++;
                  if (sscanf(szstr, LLintP, &size) == 1) {
                    back->r.totalsize = size;
                  }
                }
                // REST?
                if (fexist(back->url_sav) && (transfer_list == 0)) {
                  strcpybuff(back->info, "rest");
                  snprintf(line, sizeof(line), "REST " LLintP, (LLint) fsize(back->url_sav));
                  send_line(soc_ctl, line);
                  get_ftp_line(soc_ctl, line, sizeof(line), timeout);
                  _CHECK_HALT_FTP;
                  if ((line[0] == '3') || (line[0] == '2')) {   // ok
                    rest_understood = 1;
                  }             // sinon tant pis 
                }
              }                 // sinon tant pis 
            }
          }
#if FTP_PASV
        }
#endif

        //
        // Post-REST
        //
#if FTP_PASV
        // Ok, se connecter
        if (port_pasv) {
          SOCaddr server;
          int server_size = sizeof(server);
          const char *error = "unknown error";

          // effacer structure
          memset(&server, 0, sizeof(server));

          // infos
          strcpybuff(back->info, "resolv");

          // résoudre
          if (adr_ip[0]) {
            hts_dns_resolve2(opt, adr_ip, &server, &error);
          } else {
            SOCaddr_copy_SOCaddr(server, server_data);
          }

          // infos
          strcpybuff(back->info, "cnxdata");
#if FTP_DEBUG
          printf("Data: Connecting to %s:%d...\n", adr_ip, port_pasv);
#endif
          if (server_size > 0) {
            // socket
            soc_dat = (T_SOC) socket(SOCaddr_sinfamily(server), SOCK_STREAM, 0);
            if (soc_dat != INVALID_SOCKET) {
              // structure: connexion au domaine internet, port 80 (ou autre)
              SOCaddr_initport(server, port_pasv);
              if (connect(soc_dat, &SOCaddr_sockaddr(server), SOCaddr_size(server)) == 0) {
                strcpybuff(back->info, "retr");
                strcpybuff(line, line_retr);
                send_line(soc_ctl, line);
                get_ftp_line(soc_ctl, line, sizeof(line), timeout);
                _CHECK_HALT_FTP;
                if (line[0] == '1') {
                  // OK
                } else {
                  deletesoc(soc_dat);
                  soc_dat = INVALID_SOCKET;
                  //
                  snprintf(back->r.msg, sizeof(back->r.msg),
                           "RETR command error: %s", linejmp(line));
                  back->r.statuscode = STATUSCODE_INVALID;
                }               // sinon on est prêts
              } else {
#if FTP_DEBUG
                printf("Data: unable to connect\n");
#endif
                deletesoc(soc_dat);
                soc_dat = INVALID_SOCKET;
                //
                strcpybuff(back->r.msg, "Unable to connect");
                back->r.statuscode = STATUSCODE_INVALID;
              }                 // sinon on est prêts
            } else {
              strcpybuff(back->r.msg, "Unable to create a socket");
              back->r.statuscode = STATUSCODE_INVALID;
            }                   // sinon on est prêts
          } else {
            snprintf(back->r.msg, sizeof(back->r.msg),
                     "Unable to resolve IP %s: %s", adr_ip, error);
            back->r.statuscode = STATUSCODE_INVALID;
          }                     // sinon on est prêts
        } else {
          snprintf(back->r.msg, sizeof(back->r.msg), "PASV incorrect: %s",
                   linejmp(line));
          back->r.statuscode = STATUSCODE_INVALID;
        }                       // sinon on est prêts
#else
        //T_SOC soc_servdat;
        strcpybuff(back->info, "listening");
        if ((soc_servdat = get_datasocket(line, sizeof(line))) != INVALID_SOCKET) {
          _CHECK_HALT_FTP;
          send_line(soc_ctl, line);     // envoi du RETR
          get_ftp_line(soc_ctl, line, sizeof(line), timeout);
          _CHECK_HALT_FTP;
          if (line[0] == '2') { // ok
            strcpybuff(back->info, "retr");
            strcpybuff(line, line_retr);
            send_line(soc_ctl, line);
            get_ftp_line(soc_ctl, line, sizeof(line), timeout);
            _CHECK_HALT_FTP;
            if (line[0] == '1') {
              //T_SOC soc_dat;
              if ((soc_dat = accept(soc_servdat, NULL, NULL)) == INVALID_SOCKET) {
                strcpybuff(back->r.msg, "Unable to accept connection");
                back->r.statuscode = STATUSCODE_INVALID;
              }
            } else {
              snprintf(back->r.msg, sizeof(back->r.msg),
                       "RETR command error: %s", linejmp(line));
              back->r.statuscode = STATUSCODE_INVALID;
            }
          } else {
            snprintf(back->r.msg, sizeof(back->r.msg), "PORT command error: %s",
                     linejmp(line));
            back->r.statuscode = STATUSCODE_INVALID;
          }
#ifdef _WIN32
          closesocket(soc_servdat);
#else
          close(soc_servdat);
#endif
        } else {
          strcpybuff(back->r.msg, "Unable to listen to a port");
          back->r.statuscode = STATUSCODE_INVALID;
        }
#endif

        //
        // Ok, connexion initiée
        //
        if (soc_dat != INVALID_SOCKET) {
          if (rest_understood) {        // REST envoyée et comprise
            file_notify(opt, back->url_adr, back->url_fil, back->url_sav, 0, 1,
                        0);
            back->r.fp = fileappend(&opt->state.strc, back->url_sav);
          } else {
            file_notify(opt, back->url_adr, back->url_fil, back->url_sav, 1, 1,
                        0);
            back->r.fp = filecreate(&opt->state.strc, back->url_sav);
          }
          strcpybuff(back->info, "receiving");
          if (back->r.fp != NULL) {
            char BIGSTK buff[1024];
            int len = 1;
            int read_len = 1024;

            while((len > 0) && (!stop_ftp(back))) {
              // attendre les données
              len = 1;          // pas d'erreur pour le moment
              switch (wait_socket_receive(soc_dat, timeout)) {
              case -1:
                strcpybuff(back->r.msg, "FTP read error");
                back->r.statuscode = STATUSCODE_INVALID;
                len = 0;        // fin
                break;
              case 0:
                snprintf(back->r.msg, sizeof(back->r.msg), "Time out (%d)",
                         timeout);
                back->r.statuscode = STATUSCODE_INVALID;
                len = 0;        // fin
                break;
              }

              // réception
              if (len) {
                len = recv(soc_dat, buff, read_len, 0);
                if (len > 0) {
                  back->r.size += len;
                  HTS_STAT.HTS_TOTAL_RECV += len;
                  if (back->r.fp) {
                    if ((INTsys) fwrite(buff, 1, (INTsys) len, back->r.fp) !=
                        len) {
                      /*
                         int fcheck;
                         if ((fcheck=check_fatal_io_errno())) {
                         opt->state.exit_xh=-1;
                         }
                       */
                      strcpybuff(back->r.msg, "Write error");
                      back->r.statuscode = STATUSCODE_INVALID;
                      len = 0;  // error
                    }
                  } else {
                    strcpybuff(back->r.msg, "Unexpected write error");
                    back->r.statuscode = STATUSCODE_INVALID;
                  }
                } else { // Erreur ou terminé
                  back->r.statuscode = 0;
                  if (back->r.totalsize > 0
                      && back->r.size != back->r.totalsize) {
                    back->r.statuscode = STATUSCODE_INVALID;
                    strcpybuff(back->r.msg, "FTP file incomplete");
                  }
                }
                read_len = 1024;
              }
            }
            if (back->r.fp) {
              fclose(back->r.fp);
              back->r.fp = NULL;
            }
          } else {
            strcpybuff(back->r.msg, "Unable to write file");
            back->r.statuscode = STATUSCODE_INVALID;
          }
#ifdef _WIN32
          closesocket(soc_dat);
#else
          close(soc_dat);
#endif

          // 226 Transfer complete?
          if (back->r.statuscode != -1) {
            if (wait_socket_receive(soc_ctl, timeout_onfly) > 0) {
              // récupérer 226 transfer complete
              get_ftp_line(soc_ctl, line, sizeof(line), timeout);
              if (line[0] == '2') {     // OK
                strcpybuff(back->r.msg, "OK");
                back->r.statuscode = HTTP_OK;
              } else {
                snprintf(back->r.msg, sizeof(back->r.msg), "RETR incorrect: %s",
                         linejmp(line));
                back->r.statuscode = STATUSCODE_INVALID;
              }
            } else {
              strcpybuff(back->r.msg, "FTP read error");
              back->r.statuscode = STATUSCODE_INVALID;
            }
          }

        }

      }

    }

    _CHECK_HALT_FTP;
    strcpybuff(back->info, "quit");
    send_line(soc_ctl, "QUIT"); // bye bye
    get_ftp_line(soc_ctl, NULL, 0, timeout);
#ifdef _WIN32
    closesocket(soc_ctl);
#else
    close(soc_ctl);
#endif
  }

  if (back->r.statuscode != -1) {
    back->r.statuscode = HTTP_OK;
    strcpybuff(back->r.msg, "OK");
  }
  return 0;
}

// ouverture d'un port
T_SOC get_datasocket(char *to_send, size_t to_send_size) {
  T_SOC soc = INVALID_SOCKET;
  char h_loc[256 + 2];

  to_send[0] = '\0';
  if (gethostname(h_loc, 256) == 0) {   // host name
    SOCaddr server;

    if (hts_dns_resolve_nocache(h_loc, &server) != NULL) {   // notre host
      if ((soc =
           (T_SOC) socket(SOCaddr_sinfamily(server), SOCK_STREAM,
                          0)) != INVALID_SOCKET) {

        if (bind(soc, &SOCaddr_sockaddr(server), SOCaddr_size(server)) == 0) {
          SOCaddr server2;
          SOClen len = SOCaddr_capacity(server2);

          if (getsockname(soc, &SOCaddr_sockaddr(server2), &len) == 0) {
            // *port=ntohs(server.sin_port);  // récupérer port
            if (listen(soc, 1) >= 0) {
#if HTS_INET6==0
              unsigned short int a, n1, n2;

              // calculer port
              a = SOCaddr_sinport(server2);
              n1 = (a & 0xff);
              n2 = ((a >> 8) & 0xff);
              {
                char dots[256 + 2];
                char dot[256 + 2];
                char *a;

                SOCaddr_inetntoa(dot, 256, server2);
                //
                dots[0] = '\0';
                strncatbuff(dots, dot, 128);
                while((a = strchr(dots, '.')))
                  *a = ',';     // virgules!
                while((a = strchr(dots, ':')))
                  *a = ',';     // virgules!
                snprintf(to_send, to_send_size, "PORT %s,%d,%d", dots, n1, n2);
              }
#else
              /*
                 EPRT |1|132.235.1.2|6275|
                 EPRT |2|1080::8:800:200C:417A|5282|
               */
              {
                char dot[256 + 2];

                SOCaddr_inetntoa(dot, 256, server2);
                snprintf(to_send, to_send_size, "EPRT |%c|%s|%d|",
                         SOCaddr_getproto(server2), dot,
                         SOCaddr_sinport(server2));
              }
#endif

            } else {
#ifdef _WIN32
              closesocket(soc);
#else
              close(soc);
#endif
              soc = INVALID_SOCKET;
            }

          } else {
#ifdef _WIN32
            closesocket(soc);
#else
            close(soc);
#endif
            soc = INVALID_SOCKET;
          }

        } else {
#ifdef _WIN32
          closesocket(soc);
#else
          close(soc);
#endif
          soc = INVALID_SOCKET;
        }
      }
    }
  }

  return soc;
}

#if FTP_DEBUG
FILE *dd = NULL;
#endif

// routines de réception/émission
// 0 = ERROR
int send_line(T_SOC soc, const char *data) {
  char BIGSTK line[1024];

  if (_DEBUG_HEAD) {
    if (ioinfo) {
      fprintf(ioinfo, "---> %s\x0d\x0a", data);
      fflush(ioinfo);
    }
  }
#if FTP_DEBUG
  if (dd == NULL)
    dd = fopen("toto.txt", "w");
  fprintf(dd, "---> %s\x0d\x0a", data);
  fflush(dd);
  printf("---> %s", data);
  fflush(stdout);
#endif
  snprintf(line, sizeof(line), "%s\x0d\x0a", data);
  if (check_socket_connect(soc) != 1) {
#if FTP_DEBUG
    printf("!SOC WRITE ERROR\n");
#endif
    return 0;                   // erreur, plus connecté!
  }
#if FTP_DEBUG
  {
    int r = (send(soc, line, strlen(line), 0) == (int) strlen(line));

    printf("%s\x0d\x0a", data);
    fflush(stdout);
    return r;
  }
#else
  return (send(soc, line, (int) strlen(line), 0) == (int) strlen(line));
#endif
}

int get_ftp_line(T_SOC soc, char *ptrline, size_t line_size, int timeout) {
  char BIGSTK data[1024];
  int i, ok, multiline;

#if FTP_DEBUG
  if (dd == NULL)
    dd = fopen("toto.txt", "w");
#endif

  data[0] = '\0';
  i = ok = multiline = 0;
  data[3] = '\0';
  do {
    char b;

    // vérifier données
    switch (wait_socket_receive(soc, timeout)) {
    case -1:                   // erreur de lecture
      if (ptrline)
        snprintf(ptrline, line_size, "500 *read error");
      return 0;
      break;
    case 0:
      if (ptrline)
        snprintf(ptrline, line_size, "500 *read timeout (%d)", timeout);
      return 0;
      break;
    }

    switch (recv(soc, &b, 1, 0)) {
    case 1:
      HTS_STAT.HTS_TOTAL_RECV += 1;     // compter flux entrant
      if ((b != 10) && (b != 13) && (i < (int) sizeof(data) - 1))
        data[i++] = b; // truncate hostile over-long reply lines
      break;
    default:
      if (ptrline)
        snprintf(ptrline, line_size, "500 *read error");
      return 0;                 // error
      break;
    }
    if (((b == 13) || (b == 10)) && (i > 0)) {  // CR/LF
      if ((data[3] == '-')
          || ((multiline) && (!isdigit((unsigned char) data[0])))
        ) {
        data[3] = '\0';
        i = 0;
        multiline = 1;
      } else
        ok = 1;                 // sortir
    }
  } while(!ok);
  data[i++] = '\0';

  if (_DEBUG_HEAD) {
    if (ioinfo) {
      fprintf(ioinfo, "<--- %s\x0d\x0a", data);
      fflush(ioinfo);
    }
  }
#if FTP_DEBUG
  fprintf(dd, "<--- %s\n", data);
  fflush(dd);
  printf("<--- %s\n", data);
#endif
  if (ptrline)
    snprintf(ptrline, line_size, "%s", data);
  return (strnotempty(data));
}

// sauter NNN
char *linejmp(char *line) {
  if (strlen(line) > 4)
    return line + 4;
  else
    return line;
}

// test socket:
// 0 : no data
// 1 : data detected
// -1: error
int check_socket(T_SOC soc) {
  fd_set fds, fds_e;            // poll structures
  struct timeval tv;            // structure for select

  FD_ZERO(&fds);
  FD_ZERO(&fds_e);
  // socket read 
  FD_SET(soc, &fds);
  // socket error
  FD_SET(soc, &fds_e);
  tv.tv_sec = 0;
  tv.tv_usec = 0;
  // poll!     
  select((int) soc + 1, &fds, NULL, &fds_e, &tv);
  if (FD_ISSET(soc, &fds_e)) {  // error detected
    return -1;
  } else if (FD_ISSET(soc, &fds)) {
    return 1;
  }
  return 0;
}

// check if connected
int check_socket_connect(T_SOC soc) {
  fd_set fds, fds_e;            // poll structures
  struct timeval tv;            // structure for select

  FD_ZERO(&fds);
  FD_ZERO(&fds_e);
  // socket write 
  FD_SET(soc, &fds);
  // socket error
  FD_SET(soc, &fds_e);
  tv.tv_sec = 0;
  tv.tv_usec = 0;
  // poll!     
  select((int) soc + 1, NULL, &fds, &fds_e, &tv);
  if (FD_ISSET(soc, &fds_e)) {  // error detected
    return -1;
  } else if (FD_ISSET(soc, &fds)) {
    return 1;
  }
  return 0;
}

// attendre des données
int wait_socket_receive(T_SOC soc, int timeout) {
  // attendre les données
  TStamp ltime = time_local();
  int r;

#if FTP_DEBUG
  printf("\x0dWaiting for data ");
  fflush(stdout);
#endif
  while((!(r = check_socket(soc)))
        && (((int) ((TStamp) (time_local() - ltime))) < timeout)) {
    Sleep(100);
#if FTP_DEBUG
    printf(".");
    fflush(stdout);
#endif
  }
#if FTP_DEBUG
  printf("\x0dreturn: %d\x0d", r);
  fflush(stdout);
#endif
  return r;
}

// cancel reçu?
int stop_ftp(lien_back * back) {
  if (back->stop_ftp) {
    strcpybuff(back->r.msg, "Cancelled by User");
    back->r.statuscode = STATUSCODE_INVALID;
    return 1;
  }
  return 0;
}
