curl/tests/server/sws.c

/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2007, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at http://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 * $Id$
 ***************************************************************************/

/* sws.c: simple (silly?) web server

   This code was originally graciously donated to the project by Juergen
   Wilke. Thanks a bunch!

 */
#include "setup.h" /* portability help from the lib directory */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <signal.h>
#include <time.h>
#include <sys/time.h>
#include <sys/types.h>
#include <ctype.h>

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef _XOPEN_SOURCE_EXTENDED
/* This define is "almost" required to build on HPUX 11 */
#include <arpa/inet.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef HAVE_NETINET_TCP_H
#include <netinet/tcp.h> /* for TCP_NODELAY */
#endif

#define ENABLE_CURLX_PRINTF
/* make the curlx header define all printf() functions to use the curlx_*
   versions instead */
#include "curlx.h" /* from the private lib dir */
#include "getpart.h"
#include "util.h"

/* include memdebug.h last */
#include "memdebug.h"

#if !defined(CURL_SWS_FORK_ENABLED) && defined(HAVE_FORK)
/*
 * The normal sws build for the plain standard curl test suite has no use for
 * fork(), but if you feel wild and crazy and want to setup some more exotic
 * tests. Define this and run...
 */
#define CURL_SWS_FORK_ENABLED
#endif

#define REQBUFSIZ 150000
#define REQBUFSIZ_TXT "149999"

long prevtestno=-1; /* previous test number we served */
long prevpartno=-1; /* previous part number we served */
bool prevbounce;    /* instructs the server to increase the part number for
                       a test in case the identical testno+partno request
                       shows up again */

#define RCMD_NORMALREQ 0 /* default request, use the tests file normally */
#define RCMD_IDLE      1 /* told to sit idle */
#define RCMD_STREAM    2 /* told to stream */

struct httprequest {
  char reqbuf[REQBUFSIZ]; /* buffer area for the incoming request */
  int checkindex; /* where to start checking of the request */
  int offset;     /* size of the incoming request */
  long testno;     /* test number found in the request */
  long partno;     /* part number found in the request */
  int open;       /* keep connection open info, as found in the request */
  bool auth_req;  /* authentication required, don't wait for body unless
                     there's an Authorization header */
  bool auth;      /* Authorization header present in the incoming request */
  size_t cl;      /* Content-Length of the incoming request */
  bool digest;    /* Authorization digest header found */
  bool ntlm;      /* Authorization ntlm header found */
  int pipe;       /* if non-zero, expect this many requests to do a "piped"
                     request/response */
  int rcmd;       /* doing a special command, see defines above */
};

int ProcessRequest(struct httprequest *req);
void storerequest(char *reqbuf);

#define DEFAULT_PORT 8999

#ifndef DEFAULT_LOGFILE
#define DEFAULT_LOGFILE "log/sws.log"
#endif

const char *serverlogfile = DEFAULT_LOGFILE;

#define SWSVERSION "cURL test suite HTTP server/0.1"

#define REQUEST_DUMP  "log/server.input"
#define RESPONSE_DUMP "log/server.response"

/* very-big-path support */
#define MAXDOCNAMELEN 140000
#define MAXDOCNAMELEN_TXT "139999"

#define REQUEST_KEYWORD_SIZE 256

#define CMD_AUTH_REQUIRED "auth_required"

/* 'idle' means that it will accept the request fine but never respond
   any data. Just keep the connection alive. */
#define CMD_IDLE "idle"

/* 'stream' means to send a never-ending stream of data */
#define CMD_STREAM "stream"

#define END_OF_HEADERS "\r\n\r\n"

enum {
  DOCNUMBER_NOTHING = -7,
  DOCNUMBER_QUIT    = -6,
  DOCNUMBER_BADCONNECT = -5,
  DOCNUMBER_INTERNAL= -4,
  DOCNUMBER_CONNECT = -3,
  DOCNUMBER_WERULEZ = -2,
  DOCNUMBER_404     = -1
};


/* sent as reply to a QUIT */
static const char *docquit =
"HTTP/1.1 200 Goodbye" END_OF_HEADERS;

/* sent as reply to a CONNECT */
static const char *docconnect =
"HTTP/1.1 200 Mighty fine indeed" END_OF_HEADERS;

/* sent as reply to a "bad" CONNECT */
static const char *docbadconnect =
"HTTP/1.1 501 Forbidden you fool" END_OF_HEADERS;

/* send back this on 404 file not found */
static const char *doc404 = "HTTP/1.1 404 Not Found\r\n"
    "Server: " SWSVERSION "\r\n"
    "Connection: close\r\n"
    "Content-Type: text/html"
    END_OF_HEADERS
    "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">\n"
    "<HTML><HEAD>\n"
    "<TITLE>404 Not Found</TITLE>\n"
    "</HEAD><BODY>\n"
    "<H1>Not Found</H1>\n"
    "The requested URL was not found on this server.\n"
    "<P><HR><ADDRESS>" SWSVERSION "</ADDRESS>\n" "</BODY></HTML>\n";

#ifdef SIGPIPE
static volatile int sigpipe;  /* Why? It's not used */
#endif

#ifdef SIGPIPE
static void sigpipe_handler(int sig)
{
  (void)sig; /* prevent warning */
  sigpipe = 1;
}
#endif

int ProcessRequest(struct httprequest *req)
{
  char *line=&req->reqbuf[req->checkindex];
  char chunked=FALSE;
  static char request[REQUEST_KEYWORD_SIZE];
  static char doc[MAXDOCNAMELEN];
  char logbuf[256];
  int prot_major, prot_minor;
  char *end;
  int error;
  end = strstr(line, END_OF_HEADERS);

  logmsg("ProcessRequest() called");

  /* try to figure out the request characteristics as soon as possible, but
     only once! */
  if((req->testno == DOCNUMBER_NOTHING) &&
     sscanf(line, "%" REQBUFSIZ_TXT"s %" MAXDOCNAMELEN_TXT "s HTTP/%d.%d",
            request,
            doc,
            &prot_major,
            &prot_minor) == 4) {
    char *ptr;

    /* find the last slash */
    ptr = strrchr(doc, '/');

    /* get the number after it */
    if(ptr) {
      FILE *stream;
      char *filename;

      if((strlen(doc) + strlen(request)) < 200)
        sprintf(logbuf, "Got request: %s %s HTTP/%d.%d",
                request, doc, prot_major, prot_minor);
      else
        sprintf(logbuf, "Got a *HUGE* request HTTP/%d.%d",
                prot_major, prot_minor);
      logmsg("%s", logbuf);

      if(!strncmp("/verifiedserver", ptr, 15)) {
        logmsg("Are-we-friendly question received");
        req->testno = DOCNUMBER_WERULEZ;
        return 1; /* done */
      }

      if(!strncmp("/quit", ptr, 5)) {
        logmsg("Request-to-quit received");
        req->testno = DOCNUMBER_QUIT;
        return 1; /* done */
      }

      ptr++; /* skip the slash */

      /* skip all non-numericals following the slash */
      while(*ptr && !ISDIGIT(*ptr))
        ptr++;

      req->testno = strtol(ptr, &ptr, 10);

      if(req->testno > 10000) {
        req->partno = req->testno % 10000;
        req->testno /= 10000;
      }
      else
        req->partno = 0;

      sprintf(logbuf, "Requested test number %ld part %ld",
              req->testno, req->partno);

      logmsg("%s", logbuf);

      filename = test2file(req->testno);

      stream=fopen(filename, "rb");
      if(!stream) {
        error = ERRNO;
        logmsg("fopen() failed with error: %d %s", error, strerror(error));
        logmsg("Error opening file: %s", filename);
        logmsg("Couldn't open test file %d", req->testno);
        req->open = FALSE; /* closes connection */
        return 1; /* done */
      }
      else {
        char *cmd = NULL;
        size_t cmdsize = 0;
        int num=0;

        /* get the custom server control "commands" */
        cmd = (char *)spitout(stream, "reply", "servercmd", &cmdsize);
        fclose(stream);

        if(cmdsize) {
          logmsg("Found a reply-servercmd section!");

          if(!strncmp(CMD_AUTH_REQUIRED, cmd, strlen(CMD_AUTH_REQUIRED))) {
            logmsg("instructed to require authorization header");
            req->auth_req = TRUE;
          }
          else if(!strncmp(CMD_IDLE, cmd, strlen(CMD_IDLE))) {
            logmsg("instructed to idle");
            req->rcmd = RCMD_IDLE;
            req->open = TRUE;
          }
          else if(!strncmp(CMD_STREAM, cmd, strlen(CMD_STREAM))) {
            logmsg("instructed to stream");
            req->rcmd = RCMD_STREAM;
          }
          else if(1 == sscanf(cmd, "pipe: %d", &num)) {
            logmsg("instructed to allow a pipe size %d", num);
            req->pipe = num-1; /* decrease by one since we don't count the
                                  first request in this number */
          }
          free(cmd);
        }
      }
    }
    else {
      if(sscanf(req->reqbuf, "CONNECT %" MAXDOCNAMELEN_TXT "s HTTP/%d.%d",
                doc, &prot_major, &prot_minor) == 3) {
        sprintf(logbuf, "Received a CONNECT %s HTTP/%d.%d request",
                doc, prot_major, prot_minor);
        logmsg("%s", logbuf);

        if(prot_major*10+prot_minor == 10)
          req->open = FALSE; /* HTTP 1.0 closes connection by default */

        if(!strncmp(doc, "bad", 3))
          /* if the host name starts with bad, we fake an error here */
          req->testno = DOCNUMBER_BADCONNECT;
        else if(!strncmp(doc, "test", 4)) {
          /* if the host name starts with test, the port number used in the
             CONNECT line will be used as test number! */
          char *portp = strchr(doc, ':');
          if(portp)
            req->testno = atoi(portp+1);
          else
            req->testno = DOCNUMBER_CONNECT;
        }
        else
          req->testno = DOCNUMBER_CONNECT;
      }
      else {
        logmsg("Did not find test number in PATH");
        req->testno = DOCNUMBER_404;
      }
    }
  }

  if(!end) {
    /* we don't have a complete request yet! */
    logmsg("ProcessRequest returned without a complete request");
    return 0;
  }
  logmsg("ProcessRequest found a complete request");

  if(req->pipe)
    /* we do have a full set, advance the checkindex to after the end of the
       headers, for the pipelining case mostly */
    req->checkindex += (end - line) + strlen(END_OF_HEADERS);

  /* **** Persistancy ****
   *
   * If the request is a HTTP/1.0 one, we close the connection unconditionally
   * when we're done.
   *
   * If the request is a HTTP/1.1 one, we MUST check for a "Connection:"
   * header that might say "close". If it does, we close a connection when
   * this request is processed. Otherwise, we keep the connection alive for X
   * seconds.
   */

  do {
    if(!req->cl && curlx_strnequal("Content-Length:", line, 15)) {
      /* If we don't ignore content-length, we read it and we read the whole
         request including the body before we return. If we've been told to
         ignore the content-length, we will return as soon as all headers
         have been received */
      req->cl = strtol(line+15, &line, 10);

      logmsg("Found Content-Length: %d in the request", req->cl);
      break;
    }
    else if(curlx_strnequal("Transfer-Encoding: chunked", line,
                            strlen("Transfer-Encoding: chunked"))) {
      /* chunked data coming in */
      chunked = TRUE;
    }

    if(chunked) {
      if(strstr(req->reqbuf, "\r\n0\r\n\r\n"))
        /* end of chunks reached */
        return 1; /* done */
      else
        return 0; /* not done */
    }

    line = strchr(line, '\n');
    if(line)
      line++;
  } while(line);

  if(!req->auth && strstr(req->reqbuf, "Authorization:")) {
    req->auth = TRUE; /* Authorization: header present! */
    if(req->auth_req)
      logmsg("Authorization header found, as required");
  }

  if(!req->digest && strstr(req->reqbuf, "Authorization: Digest")) {
    /* If the client is passing this Digest-header, we set the part number
       to 1000. Not only to spice up the complexity of this, but to make
       Digest stuff to work in the test suite. */
    req->partno += 1000;
    req->digest = TRUE; /* header found */
    logmsg("Received Digest request, sending back data %d", req->partno);
  }
  else if(!req->ntlm &&
          strstr(req->reqbuf, "Authorization: NTLM TlRMTVNTUAAD")) {
    /* If the client is passing this type-3 NTLM header */
    req->partno += 1002;
    req->ntlm = TRUE; /* NTLM found */
    logmsg("Received NTLM type-3, sending back data %d", req->partno);
    if(req->cl) {
      logmsg("  Expecting %d POSTed bytes", req->cl);
    }
  }
  else if(!req->ntlm &&
          strstr(req->reqbuf, "Authorization: NTLM TlRMTVNTUAAB")) {
    /* If the client is passing this type-1 NTLM header */
    req->partno += 1001;
    req->ntlm = TRUE; /* NTLM found */
    logmsg("Received NTLM type-1, sending back data %d", req->partno);
  }
  if(strstr(req->reqbuf, "Connection: close"))
    req->open = FALSE; /* close connection after this request */

  while(req->pipe) {
    /* scan for more header ends within this chunk */
    line = &req->reqbuf[req->checkindex];
    end = strstr(line, END_OF_HEADERS);
    if(!end)
      break;
    req->checkindex += (end - line) + strlen(END_OF_HEADERS);
    req->pipe--;
  }


  /* If authentication is required and no auth was provided, end now. This
     makes the server NOT wait for PUT/POST data and you can then make the
     test case send a rejection before any such data has been sent. Test case
     154 uses this.*/
  if(req->auth_req && !req->auth)
    return 1;

  if(req->cl) {
    if(req->cl <= strlen(end+strlen(END_OF_HEADERS)))
      return 1; /* done */
    else
      return 0; /* not complete yet */
  }

  return 1; /* done */
}

/* store the entire request in a file */
void storerequest(char *reqbuf)
{
  int error;
  ssize_t written;
  ssize_t writeleft;
  ssize_t totalsize;
  FILE *dump;

  if (reqbuf == NULL)
    return;

  totalsize = (ssize_t)strlen(reqbuf);
  if (totalsize == 0)
    return;

  do {
    dump = fopen(REQUEST_DUMP, "ab");
  } while ((dump == NULL) && ((error = ERRNO) == EINTR));
  if (dump == NULL) {
    logmsg("Error opening file %s error: %d %s",
           REQUEST_DUMP, error, strerror(error));
    logmsg("Failed to write request input to " REQUEST_DUMP);
    return;
  }

  writeleft = totalsize;
  do {
    written = (ssize_t)fwrite((void *) &reqbuf[totalsize-writeleft],
                              1, (size_t)writeleft, dump);
    if (written > 0)
      writeleft -= written;
  } while ((writeleft > 0) && ((error = ERRNO) == EINTR));

  fclose(dump);  /* close it ASAP */

  if (writeleft > 0) {
    logmsg("Error writing file %s error: %d %s",
           REQUEST_DUMP, error, strerror(error));
    logmsg("Wrote only (%d bytes) of (%d bytes) request input to %s",
           totalsize-writeleft, totalsize, REQUEST_DUMP);
  }
  else {
    logmsg("Wrote request (%d bytes) input to " REQUEST_DUMP,
           totalsize);
  }
}

/* return 0 on success, non-zero on failure */
static int get_request(curl_socket_t sock, struct httprequest *req)
{
  int fail= FALSE;
  char *reqbuf = req->reqbuf;

  /*** Init the httpreqest structure properly for the upcoming request ***/
  memset(req, 0, sizeof(struct httprequest));

  /* here's what should not be 0 from the start */
  req->testno = DOCNUMBER_NOTHING; /* safe default */
  req->open = TRUE; /* connection should remain open and wait for more
                       commands */
  req->pipe = 0;

  /*** end of httprequest init ***/

  while (req->offset < REQBUFSIZ) {
    ssize_t got = sread(sock, reqbuf + req->offset, REQBUFSIZ - req->offset);
    if (got <= 0) {
      if (got < 0) {
        logmsg("recv() returned error: %d", SOCKERRNO);
        return DOCNUMBER_INTERNAL;
      }
      logmsg("Connection closed by client");
      reqbuf[req->offset]=0;

      /* dump the request receivied so far to the external file */
      storerequest(reqbuf);
      return DOCNUMBER_INTERNAL;
    }

    logmsg("Read %d bytes", got);

    req->offset += got;

    reqbuf[req->offset] = 0;

    if(ProcessRequest(req)) {
      if(req->pipe--) {
        logmsg("Waiting for another piped request");
        continue;
      }
      break;
    }
  }

  if (req->offset >= REQBUFSIZ) {
    logmsg("Request buffer overflow, closing connection");
    reqbuf[REQBUFSIZ-1]=0;
    fail = TRUE;
    /* dump the request to an external file anyway */
  }
  else
    reqbuf[req->offset]=0;

  /* dump the request to an external file */
  storerequest(reqbuf);

  return fail; /* success */
}

/* returns -1 on failure */
static int send_doc(curl_socket_t sock, struct httprequest *req)
{
  ssize_t written;
  size_t count;
  const char *buffer;
  char *ptr;
  FILE *stream;
  char *cmd=NULL;
  size_t cmdsize=0;
  FILE *dump;
  int persistant = TRUE;
  size_t responsesize;
  int error;

  static char weare[256];

  char partbuf[80]="data";

  logmsg("Send response number %d part %d", req->testno, req->partno);

  switch(req->rcmd) {
  default:
  case RCMD_NORMALREQ:
    break; /* continue with business as usual */
  case RCMD_STREAM:
#define STREAMTHIS "a string to stream 01234567890\n"
    count = strlen(STREAMTHIS);
    while(1) {
      written = swrite(sock, STREAMTHIS, count);
      if(written != (ssize_t)count) {
        logmsg("Stopped streaming");
        break;
      }
    }
    return -1;
  case RCMD_IDLE:
    /* Do nothing. Sit idle. Pretend it rains. */
    return 0;
  }

  req->open = FALSE;

  if(req->testno < 0) {
    size_t msglen;
    char msgbuf[64];

    switch(req->testno) {
    case DOCNUMBER_QUIT:
      logmsg("Replying to QUIT");
      buffer = docquit;
      break;
    case DOCNUMBER_WERULEZ:
      /* we got a "friends?" question, reply back that we sure are */
      logmsg("Identifying ourselves as friends");
      sprintf(msgbuf, "WE ROOLZ: %d\r\n", (int)getpid());
      msglen = strlen(msgbuf);
      sprintf(weare, "HTTP/1.1 200 OK\r\nContent-Length: %d\r\n\r\n%s",
              msglen, msgbuf);
      buffer = weare;
      break;
    case DOCNUMBER_INTERNAL:
      logmsg("Bailing out due to internal error");
      return -1;
    case DOCNUMBER_CONNECT:
      logmsg("Replying to CONNECT");
      buffer = docconnect;
      break;
    case DOCNUMBER_BADCONNECT:
      logmsg("Replying to a bad CONNECT");
      buffer = docbadconnect;
      break;
    case DOCNUMBER_404:
    default:
      logmsg("Replying to with a 404");
      buffer = doc404;
      break;
    }
    ptr = NULL;
    stream=NULL;

    count = strlen(buffer);
  }
  else {
    char *filename = test2file(req->testno);

    if(0 != req->partno)
      sprintf(partbuf, "data%ld", req->partno);

    stream=fopen(filename, "rb");
    if(!stream) {
      error = ERRNO;
      logmsg("fopen() failed with error: %d %s", error, strerror(error));
      logmsg("Error opening file: %s", filename);
      logmsg("Couldn't open test file");
      return 0;
    }
    else {
      buffer = spitout(stream, "reply", partbuf, &count);
      ptr = (char *)buffer;
      fclose(stream);
    }

    /* re-open the same file again */
    stream=fopen(filename, "rb");
    if(!stream) {
      error = ERRNO;
      logmsg("fopen() failed with error: %d %s", error, strerror(error));
      logmsg("Error opening file: %s", filename);
      logmsg("Couldn't open test file");
      return 0;
    }
    else {
      /* get the custom server control "commands" */
      cmd = (char *)spitout(stream, "reply", "postcmd", &cmdsize);
      fclose(stream);
    }
  }

  dump = fopen(RESPONSE_DUMP, "ab"); /* b is for windows-preparing */
  if(!dump) {
    error = ERRNO;
    logmsg("fopen() failed with error: %d %s", error, strerror(error));
    logmsg("Error opening file: %s", RESPONSE_DUMP);
    logmsg("couldn't create logfile: " RESPONSE_DUMP);
    return -1;
  }

  /* If the word 'swsclose' is present anywhere in the reply chunk, the
     connection will be closed after the data has been sent to the requesting
     client... */
  if(strstr(buffer, "swsclose") || !count) {
    persistant = FALSE;
    logmsg("connection close instruction \"swsclose\" found in response");
  }
  if(strstr(buffer, "swsbounce")) {
    prevbounce = TRUE;
    logmsg("enable \"swsbounce\" in the next request");
  }
  else
    prevbounce = FALSE;


  responsesize = count;
  do {
    /* Ok, we send no more than 200 bytes at a time, just to make sure that
       larger chunks are split up so that the client will need to do multiple
       recv() calls to get it and thus we exercise that code better */
    size_t num = count;
    if(num > 200)
      num = 200;
    written = swrite(sock, buffer, num);
    if (written < 0) {
      fclose(dump);
      logmsg("Sending response failed and we bailed out!");
      return -1;
    }
    else {
      logmsg("Sent off %d bytes", written);
    }
    /* write to file as well */
    fwrite(buffer, 1, written, dump);

    count -= written;
    buffer += written;
  } while(count>0);

  fclose(dump);

  logmsg("Response sent (%d bytes) and written to " RESPONSE_DUMP,
         responsesize);

  if(ptr)
    free(ptr);

  if(cmdsize > 0 ) {
    char command[32];
    int num;
    ptr=cmd;
    do {
      if(2 == sscanf(ptr, "%31s %d", command, &num)) {
        if(!strcmp("wait", command)) {
          logmsg("Told to sleep for %d seconds", num);
          sleep(num); /* wait this many seconds */
        }
        else
          logmsg("Unknown command in reply command section");
      }
      ptr = strchr(ptr, '\n');
      if(ptr)
        ptr++;
      else
        ptr = NULL;
    } while(ptr && *ptr);
  }
  if(cmd)
    free(cmd);

  req->open = persistant;

  prevtestno = req->testno;
  prevpartno = req->partno;

  return 0;
}

char use_ipv6=FALSE;

int main(int argc, char *argv[])
{
  struct sockaddr_in me;
#ifdef ENABLE_IPV6
  struct sockaddr_in6 me6;
#endif /* ENABLE_IPV6 */
  curl_socket_t sock, msgsock;
  int flag;
  unsigned short port = DEFAULT_PORT;
  FILE *pidfile;
  char *pidname= (char *)".http.pid";
  struct httprequest req;
  int rc;
  int error;
  int arg=1;
#ifdef CURL_SWS_FORK_ENABLED
  bool use_fork = FALSE;
#endif

  while(argc>arg) {
    if(!strcmp("--version", argv[arg])) {
      printf("sws IPv4%s"
#ifdef CURL_SWS_FORK_ENABLED
             " FORK"
#endif
             "\n"
             ,
#ifdef ENABLE_IPV6
             "/IPv6"
#else
             ""
#endif
             );
      return 0;
    }
    else if(!strcmp("--pidfile", argv[arg])) {
      arg++;
      if(argc>arg)
        pidname = argv[arg++];
    }
    else if(!strcmp("--ipv6", argv[arg])) {
#ifdef ENABLE_IPV6
      use_ipv6=TRUE;
#endif
      arg++;
    }
#ifdef CURL_SWS_FORK_ENABLED
    else if(!strcmp("--fork", argv[arg])) {
      use_fork=TRUE;
      arg++;
    }
#endif
    else if(argc>arg) {

      if(atoi(argv[arg]))
        port = (unsigned short)atoi(argv[arg++]);

      if(argc>arg)
        path = argv[arg++];
    }
  }

#ifdef WIN32
  win32_init();
  atexit(win32_cleanup);
#else

#ifdef SIGPIPE
#ifdef HAVE_SIGNAL
  signal(SIGPIPE, sigpipe_handler);
#endif
#ifdef HAVE_SIGINTERRUPT
  siginterrupt(SIGPIPE, 1);
#endif
#endif
#endif

#ifdef ENABLE_IPV6
  if(!use_ipv6)
#endif
    sock = socket(AF_INET, SOCK_STREAM, 0);
#ifdef ENABLE_IPV6
  else
    sock = socket(AF_INET6, SOCK_STREAM, 0);
#endif

  if (CURL_SOCKET_BAD == sock) {
    logmsg("Error opening socket: %d", SOCKERRNO);
    return 1;
  }

  flag = 1;
  if (0 != setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
            (void *) &flag, sizeof(flag))) {
    logmsg("setsockopt(SO_REUSEADDR) failed: %d", SOCKERRNO);
    sclose(sock);
    return 1;
  }

#ifdef ENABLE_IPV6
  if(!use_ipv6) {
#endif
    memset(&me, 0, sizeof(me));
    me.sin_family = AF_INET;
    me.sin_addr.s_addr = INADDR_ANY;
    me.sin_port = htons(port);
    rc = bind(sock, (struct sockaddr *) &me, sizeof(me));
#ifdef ENABLE_IPV6
  }
  else {
    memset(&me6, 0, sizeof(me6));
    me6.sin6_family = AF_INET6;
    me6.sin6_addr = in6addr_any;
    me6.sin6_port = htons(port);
    rc = bind(sock, (struct sockaddr *) &me6, sizeof(me6));
  }
#endif /* ENABLE_IPV6 */
  if(0 != rc) {
    logmsg("Error binding socket: %d", SOCKERRNO);
    sclose(sock);
    return 1;
  }

  pidfile = fopen(pidname, "w");
  if(pidfile) {
    fprintf(pidfile, "%d\n", (int)getpid());
    fclose(pidfile);
  }
  else {
    error = ERRNO;
    logmsg("fopen() failed with error: %d %s", error, strerror(error));
    logmsg("Error opening file: %s", pidname);
    logmsg("Couldn't write pid file");
    sclose(sock);
    return 1;
  }

  logmsg("Running IPv%d version on port %d",
#ifdef ENABLE_IPV6
         (use_ipv6?6:4)
#else
         4
#endif
         , port );

  /* start accepting connections */
  rc = listen(sock, 5);
  if(0 != rc) {
    logmsg("listen() failed with error: %d", SOCKERRNO);
    sclose(sock);
    return 1;
  }

  while (1) {
    msgsock = accept(sock, NULL, NULL);

    if (CURL_SOCKET_BAD == msgsock) {
      printf("MAJOR ERROR: accept() failed with error: %d\n", SOCKERRNO);
      break;
    }

#ifdef CURL_SWS_FORK_ENABLED
    if(use_fork) {
      /* The fork enabled version just forks off the child and don't care
         about it anymore, so don't assume otherwise. Beware and don't do
         this at home. */
      rc = fork();
      if(-1 == rc) {
        printf("MAJOR ERROR: fork() failed!\n");
        break;
      }
    }
    else
      /* not a fork, just set rc so the following proceeds nicely */
      rc = 0;
    /* 0 is returned to the child */
    if(0 == rc) {
#endif
    logmsg("====> Client connect");

#ifdef TCP_NODELAY
    /*
     * Disable the Nagle algorithm to make it easier to send out a large
     * response in many small segments to torture the clients more.
     */
    flag = 1;
    if (setsockopt(msgsock, IPPROTO_TCP, TCP_NODELAY,
                   (void *)&flag, sizeof(flag)) == -1) {
      logmsg("====> TCP_NODELAY failed");
    }
#endif

  do {
      if(get_request(msgsock, &req))
        /* non-zero means error, break out of loop */
        break;

      if(prevbounce) {
        /* bounce treatment requested */
        if((req.testno == prevtestno) &&
           (req.partno == prevpartno)) {
          req.partno++;
          logmsg("BOUNCE part number to %ld", req.partno);
        }
      }

      send_doc(msgsock, &req);

      if((req.testno < 0) && (req.testno != DOCNUMBER_CONNECT)) {
        logmsg("special request received, no persistancy");
        break;
      }
      if(!req.open) {
        logmsg("instructed to close connection after server-reply");
        break;
      }

      if(req.open)
        logmsg("=> persistant connection request ended, awaits new request");
      /* if we got a CONNECT, loop and get another request as well! */
    } while(req.open || (req.testno == DOCNUMBER_CONNECT));

    logmsg("====> Client disconnect");
    sclose(msgsock);

    if (req.testno == DOCNUMBER_QUIT)
      break;
#ifdef CURL_SWS_FORK_ENABLED
    }
#endif
  }

  sclose(sock);

  return 0;
}