Documentation Source Text

**                   $HOST.website subdirectories, each containing web content 
**                   for a single virtual host.  If launched as root and if
**                   "--user USER" also appears on the command-line and if
**                   "--jail 0" is omitted, then the process runs in a chroot
**                   jail rooted at this directory and under the userid USER.
**                   This option is required for xinetd launch but defaults
**                   to "." for a stand-alone web server.
**
**  --port N         Run in standalone mode listening on TCP port N
**
**  --user USER      Define the user under which the process should run if
**                   originally launched as root.  This process will refuse to
**                   run as root (for security).  If this option is omitted and
**                   the process is launched as root, it will abort without
**                   processing any HTTP requests.
**

static char *zContentLength = 0; /* Content length reported in the header */
static char *zContentType = 0;   /* Content type reported in the header */
static char *zQuerySuffix = 0;   /* The part of the URL after the first ? */
static char *zAuthType = 0;      /* Authorization type (basic or digest) */
static char *zAuthArg = 0;       /* Authorization values */
static char *zRemoteUser = 0;    /* REMOTE_USER set by authorization module */
static char *zIfNoneMatch= 0;    /* The If-None-Match header value */
static char *zIfModifiedSince=0; /* The If-Modified-Since header value */
static int nIn = 0;              /* Number of bytes of input */
static int nOut = 0;             /* Number of bytes of output */
static char zReplyStatus[4];     /* Reply status code */
static int statusSent = 0;       /* True after status line is sent */
static char *zLogFile = 0;       /* Log to this file */
static int debugFlag = 0;        /* True if being debugged */
static struct timeval beginTime; /* Time when this process starts */

** Break a line at the first \n or \r character seen.
*/
static void RemoveNewline(char *z){
  if( z==0 ) return;
  while( *z && *z!='\n' && *z!='\r' ){ z++; }
  *z = 0;
}

/* Render seconds since 1970 as an RFC822 date string.  Return
** a pointer to that string in a static buffer.
*/
static char *Rfc822Date(time_t t){
  struct tm *tm;
  static char zDate[100];
  tm = gmtime(&t);
  strftime(zDate, sizeof(zDate), "%a, %d %b %Y %H:%M:%S %z", tm);
  return zDate;
}

/*
** Print a date tag in the header.  The name of the tag is zTag.
** The date is determined from the unix timestamp given.
*/
static int DateTag(const char *zTag, time_t t){
  return printf("%s: %s\r\n", zTag, Rfc822Date(t));
}

/*
** Parse an RFC822-formatted timestamp as we'd expect from HTTP and return
** a Unix epoch time. <= zero is returned on failure.
*/
time_t ParseRfc822Date(const char *zDate){
  int mday, mon, year, yday, hour, min, sec;
  char zIgnore[4];
  char zMonth[4];
  static const char *const azMonths[] =
    {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec", 0};
  if( 7==sscanf(zDate, "%3[A-Za-z], %d %3[A-Za-z] %d %d:%d:%d", zIgnore,
                       &mday, zMonth, &year, &hour, &min, &sec)){
    if( year > 1900 ) year -= 1900;
    for(mon=0; azMonths[mon]; mon++){
      if( !strncmp( azMonths[mon], zMonth, 3 )){
        int nDay;
        int isLeapYr;
        static int priorDays[] =
         {  0, 31, 59, 90,120,151,181,212,243,273,304,334 };
        if( mon<0 ){
          int nYear = (11 - mon)/12;
          year -= nYear;
          mon += nYear*12;
        }else if( mon>11 ){
          year += mon/12;
          mon %= 12;
        }
        isLeapYr = year%4==0 && (year%100!=0 || (year+300)%400==0);
        yday = priorDays[mon] + mday - 1;
        if( isLeapYr && mon>1 ) yday++;
        nDay = (year-70)*365 + (year-69)/4 - year/100 + (year+300)/400 + yday;
        return ((nDay*24 + hour)*60 + min)*60 + sec;
      }
    }
  }
  return 0;
}

/*
** Test procedure for ParseRfc822Date
*/
void TestParseRfc822Date(void){
  time_t t1, t2;
  for(t1=0; t1<0x7fffffff; t1 += 127){
    t2 = ParseRfc822Date(Rfc822Date(t1));
    assert( t1==t2 );
  }
}

/*
** Print the first line of a response followed by the server type.
*/
static void StartResponse(const char *zResultCode){
  time_t now;

  /* Get all the optional fields that follow the first line.
  */
  zCookie = 0;
  zAuthType = 0;
  zRemoteUser = 0;
  zReferer = 0;
  zIfNoneMatch = 0;
  zIfModifiedSince = 0;
  while( fgets(zLine,sizeof(zLine),stdin) ){
    char *zFieldName;
    char *zVal;

#ifdef LOG_HEADER
    if( hdrLog ) fprintf(hdrLog, "%s", zLine);
#endif

      if( zRealPort ){
        zServerPort = StrDup(zRealPort);
      }
    }else if( strcasecmp(zFieldName,"Authorization:")==0 ){
      zAuthType = GetFirstElement(StrDup(zVal), &zAuthArg);
    }else if( strcasecmp(zFieldName,"If-None-Match:")==0 ){
      zIfNoneMatch = StrDup(zVal);
    }else if( strcasecmp(zFieldName,"If-Modified-Since:")==0 ){
      zIfModifiedSince = StrDup(zVal);
    }
  }
#ifdef LOG_HEADER
  if( hdrLog ) fclose(hdrLog);
#endif

  /* Disallow requests from certain clients */

      { "CONTENT_TYPE",                &zContentType },
      { "DOCUMENT_ROOT",               &zHome },
      { "GATEWAY_INTERFACE",           &gateway_interface },
      { "HTTP_ACCEPT",                 &zAccept },
      { "HTTP_ACCEPT_ENCODING",        &zAcceptEncoding },
      { "HTTP_COOKIE",                 &zCookie },
      { "HTTP_HOST",                   &zHttpHost },
      { "HTTP_IF_MODIFIED_SINCE",      &zIfModifiedSince },
      { "HTTP_IF_NONE_MATCH",          &zIfNoneMatch },
      { "HTTP_REFERER",                &zReferer },
      { "HTTP_USER_AGENT",             &zAgent },
      { "PATH",                        &default_path },
      { "PATH_INFO",                   &zPathInfo },
      { "QUERY_STRING",                &zQueryString },
      { "REMOTE_ADDR",                 &zRemoteAddr },

    ** actual content file name, report that as a 404 error. */
    NotFound(__LINE__); /* LOG: Excess URI content past static file name */
  }else{
    /* If it isn't executable then it
    ** must a simple file that needs to be copied to output.
    */
    const char *zContentType = GetMimeType(zFile, lenFile);
    time_t t;
    char zETag[100];

    if( zTmpNam ) unlink(zTmpNam);
    sprintf(zETag, "m%xs%x", (int)statbuf.st_mtime, (int)statbuf.st_size);
    if( CompareEtags(zIfNoneMatch,zETag)==0
     || (zIfModifiedSince!=0
          && (t = ParseRfc822Date(zIfModifiedSince))>0
          && t>=statbuf.st_mtime)
    ){
      StartResponse("304 Not Modified");
      nOut += DateTag("Last-Modified", statbuf.st_mtime);
      nOut += printf("Cache-Control: max-age=%d\r\n", mxAge);
      nOut += printf("ETag: \"%s\"\r\n", zETag);
      nOut += printf("\r\n");
      fflush(stdout);
      MakeLogEntry(0, __LINE__);  /* LOG: ETag Cache Hit */
      return;
    }

      if( atoi(zArg)==0 ){
        useChrootJail = 0;
      }
    }else if( strcmp(z, "-debug")==0 ){
      if( atoi(zArg) ){
        useTimeout = 0;
      }
    }else if( strcmp(z, "-datetest")==0 ){
      TestParseRfc822Date();
      printf("Ok\n");
      exit(0);
    }else{
      Malfunction(__LINE__, /* LOG: unknown command-line argument on launch */
                  "unknown argument: [%s]\n", z);
    }
    argv += 2;
    argc -= 2;
  }