mime_util.cc

 
// -*- mode: c++; c-basic-offset:4 -*-
 
// This file is part of libdap, A C++ implementation of the OPeNDAP Data
// Access Protocol.
 
// Copyright (c) 2002,2003 OPeNDAP, Inc.
// Author: James Gallagher <jgallagher@opendap.org>
//         Reza Nekovei <rnekovei@intcomm.net>
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
//
// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.
 
// (c) COPYRIGHT URI/MIT 1994-2001
// Please read the full copyright statement in the file COPYRIGHT_URI.
//
// Authors:
//      jhrg,jimg       James Gallagher <jgallagher@gso.uri.edu>
//      reza            Reza Nekovei <rnekovei@intcomm.net>
 
// A few useful routines which are used in CGI programs.
//
// ReZa 9/30/94
 
#include "config.h"
 
#include <cstring>
#include <cstdio>
#include <ctype.h>
 
#ifndef TM_IN_SYS_TIME
#include <time.h>
#else
#include <sys/time.h>
#endif
 
#include <sys/types.h>
#include <sys/stat.h>
 
#ifndef WIN32
#include <unistd.h>    // for access
#include <sys/wait.h>
#else
#include <io.h>
#include <fcntl.h>
#include <process.h>
// Win32 does not define this. 08/21/02 jhrg
#define F_OK 0
#endif
 
#include <iostream>
#include <sstream>
#include <fstream>
#include <string>
 
#include "mime_util.h"
#include "media_types.h"
 
#include "Ancillary.h"
#include "util.h"  // This supplies flush_stream for WIN32.
#include "debug.h"
 
#ifdef WIN32
#define FILE_DELIMITER '\\'
#else  //  default to unix
#define FILE_DELIMITER '/'
#endif
 
// ...not using a const string here to avoid global objects. jhrg 12/23/05
#define CRLF "\r\n"             // Change here, expr-test.cc, in DODSFilter and ResponseBuilder
 
using namespace std;
 
namespace libdap {
 
time_t
last_modified_time(const string &name)
{
    struct stat m;
 
    if (stat(name.c_str(), &m) == 0 && (S_IFREG & m.st_mode))
        return m.st_mtime;
    else
        return time(0);
}
// Return a MIME rfc-822 date. The grammar for this is:
//       date-time   =  [ day "," ] date time        ; dd mm yy
//                                                   ;  hh:mm:ss zzz
//
//       day         =  "Mon"  / "Tue" /  "Wed"  / "Thu"
//                   /  "Fri"  / "Sat" /  "Sun"
//
//       date        =  1*2DIGIT month 2DIGIT        ; day month year
//                                                   ;  e.g. 20 Jun 82
//                   NB: year is 4 digit; see RFC 1123. 11/30/99 jhrg
//
//       month       =  "Jan"  /  "Feb" /  "Mar"  /  "Apr"
//                   /  "May"  /  "Jun" /  "Jul"  /  "Aug"
//                   /  "Sep"  /  "Oct" /  "Nov"  /  "Dec"
//
//       time        =  hour zone                    ; ANSI and Military
//
//       hour        =  2DIGIT ":" 2DIGIT [":" 2DIGIT]
//                                                   ; 00:00:00 - 23:59:59
//
//       zone        =  "UT"  / "GMT"                ; Universal Time
//                                                   ; North American : UT
//                   /  "EST" / "EDT"                ;  Eastern:  - 5/ - 4
//                   /  "CST" / "CDT"                ;  Central:  - 6/ - 5
//                   /  "MST" / "MDT"                ;  Mountain: - 7/ - 6
//                   /  "PST" / "PDT"                ;  Pacific:  - 8/ - 7
//                   /  1ALPHA                       ; Military: Z = UT;
//                                                   ;  A:-1; (J not used)
//                                                   ;  M:-12; N:+1; Y:+12
//                   / ( ("+" / "-") 4DIGIT )        ; Local differential
//                                                   ;  hours+min. (HHMM)
 
static const char *days[] =
    {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
    };
static const char *months[] =
    {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul",
     "Aug", "Sep", "Oct", "Nov", "Dec"
    };
 
#ifdef _MSC_VER
#define snprintf sprintf_s
#endif
string
rfc822_date(const time_t t)
{
    struct tm *stm = gmtime(&t);
    if (!stm)
        return "";
 
    char d[256];
 
    snprintf(d, 255, "%s, %02d %s %4d %02d:%02d:%02d GMT", days[stm->tm_wday],
            stm->tm_mday, months[stm->tm_mon],
            1900 + stm->tm_year,
            stm->tm_hour, stm->tm_min, stm->tm_sec);
    d[255] = '\0';
    return string(d);
}
 
static const int TimLen = 26; // length of string from asctime()
//static const int CLUMP_SIZE = 1024; // size of clumps to new in fmakeword()
 
bool
do_version(const string &script_ver, const string &dataset_ver)
{
    fprintf(stdout, "HTTP/1.0 200 OK%s", CRLF) ;
    fprintf(stdout, "XDODS-Server: %s%s", DVR, CRLF) ;
    fprintf(stdout, "XOPeNDAP-Server: %s%s", DVR, CRLF) ;
    fprintf(stdout, "XDAP: %s%s", DAP_PROTOCOL_VERSION, CRLF) ;
    fprintf(stdout, "Content-Type: text/plain%s", CRLF) ;
    fprintf(stdout, CRLF) ;
 
    fprintf(stdout, "Core software version: %s%s", DVR, CRLF) ;
 
    if (script_ver != "")
        fprintf(stdout, "Server Script Revision: %s%s", script_ver.c_str(), CRLF) ;
 
    if (dataset_ver != "")
        fprintf(stdout,  "Dataset version: %s%s", dataset_ver.c_str(), CRLF) ;
 
    fflush(stdout) ;            // Not sure this is needed. jhrg 12/23/05
 
    return true;
}
 
void
ErrMsgT(const string &Msgt)
{
    time_t TimBin;
    char TimStr[TimLen];
 
    if (time(&TimBin) == (time_t) - 1)
        strncpy(TimStr, "time() error           ", TimLen-1);
    else {
        char *ctime_value = ctime(&TimBin);
        if (!ctime_value)
                strncpy(TimStr, "Unknown", TimLen-1);
        else {
                strncpy(TimStr, ctime_value, TimLen-1);
                TimStr[TimLen - 2] = '\0'; // overwrite the \n
        }
#if 0
        strncpy(TimStr, ctime(&TimBin), TimLen-1);
        TimStr[TimLen - 2] = '\0'; // overwrite the \n
#endif
    }
 
    cerr << "[" << TimStr << "] DAP server error: " << Msgt << endl;
}
 
// Given a pathname, return just the filename component with any extension
// removed. The new string resides in newly allocated memory; the caller must
// delete it when done using the filename.
// Originally from the netcdf distribution (ver 2.3.2).
//
// *** Change to string class argument and return type. jhrg
// *** Changed so it also removes the#path#of#the#file# from decompressed
//     files.  rph.
// Returns: A filename, with path and extension information removed. If
// memory for the new name cannot be allocated, does not return!
 
string
name_path(const string &path)
{
    if (path == "")
        return string("");
 
    string::size_type delim = path.find_last_of(FILE_DELIMITER);
    string::size_type pound = path.find_last_of("#");
    string new_path;
 
    if (pound != string::npos)
        new_path = path.substr(pound + 1);
    else
        new_path = path.substr(delim + 1);
 
    return new_path;
}
 
// Send string to set the transfer (mime) type and server version
// Note that the content description filed is used to indicate whether valid
// information of an error message is contained in the document and the
// content-encoding field is used to indicate whether the data is compressed.
// If the data stream is to be compressed, arrange for a compression output
// filter so that all information sent after the header will be compressed.
//
// Returns: false if the compression output filter was to be used but could
// not be started, true otherwise.
#if 0
static const char *descrip[] =
    {"unknown", "dods_das", "dods_dds", "dods_data", "dods_ddx",
     "dods_error", "web_error", "dap4-dmr", "dap4-data", "dap4-error"
    };
#endif
 
static const char *descrip[] = {
"unknown_type",
"dods_das",
"dods_dds",
"dods_data",
"dods_ddx",       // This is the old XML DDS/DAS used prior to dap4
"dods_data_ddx",  // This is used for caching data responses
"dods_error",
"web_error",
 
"dap4_dmr",       // DAP4 metadata
"dap4_data",      // The DMR with a data blob
"dap4_error"      // The error response for DAP4
};
 
static const char *encoding[] =
    {"unknown", "deflate", "x-plain", "gzip", "binary"
    };
 
ObjectType
get_type(const string &value)
{
        return get_description_type(value);
}
 
// TODO Recode to use the constants in media_types.h. jhrg 11/12/13
 
ObjectType
get_description_type(const string &value)
{
    if ((value == DAS1) || (value == "dods-das"))
        return dods_das;
    else if ((value == "dods_dds") || (value == "dods-dds"))
        return dods_dds;
    else if ((value == "dods_data") || (value == "dods-data"))
        return dods_data;
    else if ((value == "dods_ddx") || (value == "dods-ddx"))
        return dods_ddx;
    else if ((value == "dods_data_ddx" || (value == "dods-data-ddx")))
        return dods_data_ddx;
    else if ((value == "dods_error") || (value == "dods-error"))
        return dods_error;
    else if ((value == "web_error") || (value == "web-error"))
        return web_error;
 
    else if ((value == "dap4_dmr") || (value == "dap4-dmr") || (value == DMR_Content_Type))
        return dap4_dmr;
    else if ((value == "dap4_data") || (value == "dap4-data") || (value == DAP4_DATA_Content_Type))
        return dap4_data;
    else if ((value == "dap4_error") || (value == "dap4-error"))
        return dap4_error;
 
    else
        return unknown_type;
}
 
void
set_mime_text(FILE *out, ObjectType type, const string &ver,
              EncodingType enc, const time_t last_modified)
{
    ostringstream oss;
    set_mime_text(oss, type, ver, enc, last_modified);
    fwrite(oss.str().data(), 1, oss.str().length(), out);
}
 
void
set_mime_text(ostream &strm, ObjectType type, const string &ver,
              EncodingType enc, const time_t last_modified)
{
    strm << "HTTP/1.0 200 OK" << CRLF ;
    if (ver == "") {
        strm << "XDODS-Server: " << DVR << CRLF ;
        strm << "XOPeNDAP-Server: " << DVR << CRLF ;
    }
    else {
        strm << "XDODS-Server: " << ver.c_str() << CRLF ;
        strm << "XOPeNDAP-Server: " << ver.c_str() << CRLF ;
    }
    strm << "XDAP: " << DAP_PROTOCOL_VERSION << CRLF ;
 
    const time_t t = time(0);
    strm << "Date: " << rfc822_date(t).c_str() << CRLF ;
 
    strm << "Last-Modified: " ;
    if (last_modified > 0)
        strm << rfc822_date(last_modified).c_str() << CRLF ;
    else
        strm << rfc822_date(t).c_str() << CRLF ;
 
    if (type == dap4_dmr)
        strm << "Content-Type: application/vnd.org.opendap.dap4.dataset-metadata+xml" << CRLF ;
    else
        strm << "Content-Type: text/plain" << CRLF ;
 
    // Note that Content-Description is from RFC 2045 (MIME, pt 1), not 2616.
    // jhrg 12/23/05
    strm << "Content-Description: " << descrip[type] << CRLF ;
    if (type == dods_error) // don't cache our error responses.
        strm << "Cache-Control: no-cache" << CRLF ;
    // Don't write a Content-Encoding header for x-plain since that breaks
    // Netscape on NT. jhrg 3/23/97
    if (enc != x_plain)
        strm << "Content-Encoding: " << encoding[enc] << CRLF ;
    strm << CRLF ;
}
 
void set_mime_text(ostream &strm, ObjectType type, EncodingType enc, const time_t last_modified,
        const string &protocol)
{
    strm << "HTTP/1.0 200 OK" << CRLF;
 
    strm << "XDODS-Server: " << DVR << CRLF;
    strm << "XOPeNDAP-Server: " << DVR << CRLF;
 
    if (protocol == "")
        strm << "XDAP: " << DAP_PROTOCOL_VERSION << CRLF;
    else
        strm << "XDAP: " << protocol << CRLF;
 
    const time_t t = time(0);
    strm << "Date: " << rfc822_date(t).c_str() << CRLF;
 
    strm << "Last-Modified: ";
    if (last_modified > 0)
        strm << rfc822_date(last_modified).c_str() << CRLF;
    else
        strm << rfc822_date(t).c_str() << CRLF;
 
    if (type == dap4_dmr)
        strm << "Content-Type: application/vnd.org.opendap.dap4.dataset-metadata+xml" << CRLF;
    else
        strm << "Content-Type: text/plain" << CRLF;
 
    // Note that Content-Description is from RFC 2045 (MIME, pt 1), not 2616.
    // jhrg 12/23/05
    strm << "Content-Description: " << descrip[type] << CRLF;
    if (type == dods_error) // don't cache our error responses.
        strm << "Cache-Control: no-cache" << CRLF;
    // Don't write a Content-Encoding header for x-plain since that breaks
    // Netscape on NT. jhrg 3/23/97
    if (enc != x_plain)
        strm << "Content-Encoding: " << encoding[enc] << CRLF;
    strm << CRLF;
}
 
void
set_mime_html(FILE *out, ObjectType type, const string &ver,
              EncodingType enc, const time_t last_modified)
{
    ostringstream oss;
    set_mime_html(oss, type, ver, enc, last_modified);
    fwrite(oss.str().data(), 1, oss.str().length(), out);
}
 
void
set_mime_html(ostream &strm, ObjectType type, const string &ver,
              EncodingType enc, const time_t last_modified)
{
    strm << "HTTP/1.0 200 OK" << CRLF ;
    if (ver == "") {
        strm << "XDODS-Server: " << DVR << CRLF ;
        strm << "XOPeNDAP-Server: " << DVR << CRLF ;
    }
    else {
        strm << "XDODS-Server: " << ver.c_str() << CRLF ;
        strm << "XOPeNDAP-Server: " << ver.c_str() << CRLF ;
    }
    strm << "XDAP: " << DAP_PROTOCOL_VERSION << CRLF ;
 
    const time_t t = time(0);
    strm << "Date: " << rfc822_date(t).c_str() << CRLF ;
 
    strm << "Last-Modified: " ;
    if (last_modified > 0)
        strm << rfc822_date(last_modified).c_str() << CRLF ;
    else
        strm << rfc822_date(t).c_str() << CRLF ;
 
    strm << "Content-type: text/html" << CRLF ;
    // See note above about Content-Description header. jhrg 12/23/05
    strm << "Content-Description: " << descrip[type] << CRLF ;
    if (type == dods_error) // don't cache our error responses.
        strm << "Cache-Control: no-cache" << CRLF ;
    // Don't write a Content-Encoding header for x-plain since that breaks
    // Netscape on NT. jhrg 3/23/97
    if (enc != x_plain)
        strm << "Content-Encoding: " << encoding[enc] << CRLF ;
    strm << CRLF ;
}
 
void set_mime_html(ostream &strm, ObjectType type, EncodingType enc, const time_t last_modified,
        const string &protocol)
{
    strm << "HTTP/1.0 200 OK" << CRLF;
 
    strm << "XDODS-Server: " << DVR<< CRLF;
    strm << "XOPeNDAP-Server: " << DVR<< CRLF;
 
    if (protocol == "")
        strm << "XDAP: " << DAP_PROTOCOL_VERSION << CRLF;
    else
        strm << "XDAP: " << protocol << CRLF;
 
    const time_t t = time(0);
    strm << "Date: " << rfc822_date(t).c_str() << CRLF;
 
    strm << "Last-Modified: ";
    if (last_modified > 0)
        strm << rfc822_date(last_modified).c_str() << CRLF;
    else
        strm << rfc822_date(t).c_str() << CRLF;
 
    strm << "Content-type: text/html" << CRLF;
    // See note above about Content-Description header. jhrg 12/23/05
    strm << "Content-Description: " << descrip[type] << CRLF;
    if (type == dods_error) // don't cache our error responses.
        strm << "Cache-Control: no-cache" << CRLF;
    // Don't write a Content-Encoding header for x-plain since that breaks
    // Netscape on NT. jhrg 3/23/97
    if (enc != x_plain)
        strm << "Content-Encoding: " << encoding[enc] << CRLF;
    strm << CRLF;
}
 
void
set_mime_binary(FILE *out, ObjectType type, const string &ver,
                EncodingType enc, const time_t last_modified)
{
    ostringstream oss;
    set_mime_binary(oss, type, ver, enc, last_modified);
    fwrite(oss.str().data(), 1, oss.str().length(), out);
}
 
void
set_mime_binary(ostream &strm, ObjectType type, const string &ver,
                EncodingType enc, const time_t last_modified)
{
    strm << "HTTP/1.0 200 OK" << CRLF ;
    if (ver == "") {
        strm << "XDODS-Server: " << DVR << CRLF ;
        strm << "XOPeNDAP-Server: " << DVR << CRLF ;
    }
    else {
        strm << "XDODS-Server: " << ver.c_str() << CRLF ;
        strm << "XOPeNDAP-Server: " << ver.c_str() << CRLF ;
    }
    strm << "XDAP: " << DAP_PROTOCOL_VERSION << CRLF ;
 
    const time_t t = time(0);
    strm << "Date: " << rfc822_date(t).c_str() << CRLF ;
 
    strm << "Last-Modified: " ;
    if (last_modified > 0)
        strm << rfc822_date(last_modified).c_str() << CRLF ;
    else
        strm << rfc822_date(t).c_str() << CRLF ;
 
    strm << "Content-Type: application/octet-stream" << CRLF ;
    strm << "Content-Description: " << descrip[type] << CRLF ;
    if (enc != x_plain)
        strm << "Content-Encoding: " << encoding[enc] << CRLF ;
 
    strm << CRLF ;
}
 
void set_mime_binary(ostream &strm, ObjectType type, EncodingType enc, const time_t last_modified,
        const string &protocol)
{
    strm << "HTTP/1.0 200 OK" << CRLF;
 
    strm << "XDODS-Server: " << DVR << CRLF;
    strm << "XOPeNDAP-Server: " << DVR << CRLF;
 
    if (protocol.empty())
        strm << "XDAP: " << DAP_PROTOCOL_VERSION << CRLF;
    else
        strm << "XDAP: " << protocol << CRLF;
 
    const time_t t = time(0);
    strm << "Date: " << rfc822_date(t).c_str() << CRLF;
 
    strm << "Last-Modified: ";
    if (last_modified > 0)
        strm << rfc822_date(last_modified).c_str() << CRLF;
    else
        strm << rfc822_date(t).c_str() << CRLF;
 
    strm << "Content-Type: application/octet-stream" << CRLF;
    strm << "Content-Description: " << descrip[type] << CRLF;
    if (enc != x_plain)
        strm << "Content-Encoding: " << encoding[enc] << CRLF;
 
    strm << CRLF;
}
 
void set_mime_multipart(ostream &strm, const string &boundary,
        const string &start, ObjectType type,
        const string &version, EncodingType enc,
        const time_t last_modified)
{
    strm << "HTTP/1.0 200 OK" << CRLF ;
    if (version == "") {
        strm << "XDODS-Server: " << DVR << CRLF ;
        strm << "XOPeNDAP-Server: " << DVR << CRLF ;
    }
    else {
        strm << "XDODS-Server: " << version.c_str() << CRLF ;
        strm << "XOPeNDAP-Server: " << version.c_str() << CRLF ;
    }
    strm << "XDAP: " << DAP_PROTOCOL_VERSION << CRLF ;
 
    const time_t t = time(0);
    strm << "Date: " << rfc822_date(t).c_str() << CRLF ;
 
    strm << "Last-Modified: " ;
    if (last_modified > 0)
        strm << rfc822_date(last_modified).c_str() << CRLF ;
    else
        strm << rfc822_date(t).c_str() << CRLF ;
 
    strm << "Content-Type: Multipart/Related; boundary=" << boundary
        << "; start=\"<" << start << ">\"; type=\"Text/xml\"" << CRLF ;
    strm << "Content-Description: " << descrip[type] << CRLF ;
    if (enc != x_plain)
        strm << "Content-Encoding: " << encoding[enc] << CRLF ;
 
    strm << CRLF ;
}
 
void set_mime_multipart(ostream &strm, const string &boundary, const string &start, ObjectType type, EncodingType enc,
        const time_t last_modified, const string &protocol, const string &url)
{
    strm << "HTTP/1.1 200 OK" << CRLF;
 
    const time_t t = time(0);
    strm << "Date: " << rfc822_date(t).c_str() << CRLF;
 
    strm << "Last-Modified: ";
    if (last_modified > 0)
        strm << rfc822_date(last_modified).c_str() << CRLF;
    else
        strm << rfc822_date(t).c_str() << CRLF;
 
    strm << "Content-Type: multipart/related; boundary=" << boundary << "; start=\"<" << start
            << ">\"; type=\"text/xml\"" << CRLF;
 
    // data-ddx;"; removed as a result of the merge of the hyrax 1.8 release
    // branch.
    strm << "Content-Description: " << descrip[type] << ";";
    if (!url.empty())
        strm << " url=\"" << url << "\"" << CRLF;
    else
        strm << CRLF;
 
    if (enc != x_plain)
        strm << "Content-Encoding: " << encoding[enc] << CRLF;
 
    if (protocol == "")
        strm << "X-DAP: " << DAP_PROTOCOL_VERSION << CRLF;
    else
        strm << "X-DAP: " << protocol << CRLF;
 
    strm << "X-OPeNDAP-Server: " << DVR<< CRLF;
 
    strm << CRLF;
}
 
void set_mime_ddx_boundary(ostream &strm, const string &boundary,
        const string &cid, ObjectType type, EncodingType enc)
{
    strm << "--" << boundary << CRLF;
    strm << "Content-Type: Text/xml; charset=iso-8859-1" << CRLF;
    strm << "Content-Id: <" << cid << ">" << CRLF;
    strm << "Content-Description: " << descrip[type] << CRLF ;
    if (enc != x_plain)
         strm << "Content-Encoding: " << encoding[enc] << CRLF ;
 
    strm << CRLF;
}
 
void set_mime_data_boundary(ostream &strm, const string &boundary,
        const string &cid, ObjectType type, EncodingType enc)
{
    strm << "--" << boundary << CRLF;
    strm << "Content-Type: application/octet-stream" << CRLF;
    strm << "Content-Id: <" << cid << ">" << CRLF;
    strm << "Content-Description: " << descrip[type] << CRLF ;
    if (enc != x_plain)
         strm << "Content-Encoding: " << encoding[enc] << CRLF ;
 
    strm << CRLF;
}
 
const size_t line_length = 1024;
 
string get_next_mime_header(FILE *in)
{
    // Get the header line and strip \r\n. Some headers end with just \n.
    // If a blank line is found, return an empty string.
    char line[line_length];
    while (!feof(in)) {
        if (fgets(line, line_length, in)
                && (strncmp(line, CRLF, 2) == 0 || line[0] == '\n'))
            return "";
        else {
            size_t slen = min(strlen(line), line_length); // Never > line_length
            line[slen - 1] = '\0'; // remove the newline
            if (line[slen - 2] == '\r') // ...and the preceding carriage return
                line[slen - 2] = '\0';
            return string(line);
        }
    }
 
    throw Error("I expected to find a MIME header, but got EOF instead.");
}
 
string get_next_mime_header(istream &in)
{
#if 0
    // Get the header line and strip \r\n. Some headers end with just \n.
    // If a blank line is found, return an empty string.
        char line[line_length];
        while (!in.eof()) {
                in.getline(line, line_length);
                if (strncmp(line, CRLF, 2) == 0 || line[0] == '\n') {
                        return "";
                }
                else {
                        size_t slen = min(strlen(line), line_length); // Never > line_length
                        line[slen - 1] = '\0'; // remove the newline
                        if (line[slen - 2] == '\r') // ...and the preceding carriage return
                                line[slen - 2] = '\0';
                        return string(line);
                }
        }
#endif
    // Get the header line and strip \r\n. Some headers end with just \n.
    // If a blank line is found, return an empty string.
        char raw_line[line_length];
        while (!in.eof()) {
                in.getline(raw_line, line_length); // strips the trailing newline; terminates with null
                string line = raw_line;
                if (line.find('\r') != string::npos)
                        line = line.substr(0, line.size()-1);
                return line;
        }
 
        throw Error("I expected to find a MIME header, but got EOF instead.");
}
 
void parse_mime_header(const string &header, string &name, string &value)
{
    istringstream iss(header);
 
    size_t length = header.length() + 1;
    vector<char> s(length);
    //char s[line_length];
    iss.getline(&s[0], length, ':');
    name = &s[0];
 
    iss.ignore(length, ' ');
    iss.getline(&s[0], length);
    value = &s[0];
 
    downcase(name);
    downcase(value);
}
 
bool is_boundary(const char *line, const string &boundary)
{
    if (strlen(line) < 2 || !(line[0] == '-' && line[1] == '-'))
                return false;
    else
                return strncmp(line, boundary.c_str(), boundary.length()) == 0;
}
 
string read_multipart_boundary(FILE *in, const string &boundary)
{
    string boundary_line = get_next_mime_header(in);
    // If the caller passed in a value for the boundary, test for that value,
    // else just see that this line starts with '--'.
    // The value of 'boundary_line' is returned by this function.
    if ((!boundary.empty() && is_boundary(boundary_line.c_str(), boundary))
            || boundary_line.find("--") != 0)
        throw Error(internal_error, "The DAP4 data response document is broken - missing or malformed boundary.");
 
    return boundary_line;
}
 
string read_multipart_boundary(istream &in, const string &boundary)
{
    string boundary_line = get_next_mime_header(in);
    // If the caller passed in a value for the boundary, test for that value,
    // else just see that this line starts with '--'.
    // The value of 'boundary_line' is returned by this function.
    if ((!boundary.empty() && is_boundary(boundary_line.c_str(), boundary))
            || boundary_line.find("--") != 0)
        throw Error(internal_error, "The DAP4 data response document is broken - missing or malformed boundary.");
 
    return boundary_line;
}
 
void read_multipart_headers(FILE *in, const string &content_type, const ObjectType object_type, const string &cid)
{
        bool ct = false, cd = false, ci = false;
 
        string header = get_next_mime_header(in);
        while (!header.empty()) {
                string name, value;
                parse_mime_header(header, name, value);
 
                if (name == "content-type") {
                        ct = true;
                        if (value.find(content_type) == string::npos)
                                throw Error(internal_error, "Content-Type for this part of a DAP2 data ddx response must be " + content_type + ".");
                }
                else if (name == "content-description") {
                        cd = true;
                        if (get_description_type(value) != object_type)
                                throw Error(internal_error, "Content-Description for this part of a DAP2 data ddx response must be dods-ddx or dods-data-ddx");
                }
                else if (name == "content-id") {
                        ci = true;
                        if (!cid.empty() && value != cid)
                                throw Error("Content-Id mismatch. Expected: " + cid + ", but got: " + value);
                }
 
                header = get_next_mime_header(in);
        }
 
        if (!(ct && cd && ci)) throw Error(internal_error, "The DAP4 data response document is broken - missing header.");
}
 
void read_multipart_headers(istream &in, const string &content_type, const ObjectType object_type, const string &cid)
{
        bool ct = false, cd = false, ci = false;
 
        string header = get_next_mime_header(in);
        while (!header.empty()) {
                string name, value;
                parse_mime_header(header, name, value);
 
                if (name == "content-type") {
                        ct = true;
                        if (value.find(content_type) == string::npos)
                                throw Error(internal_error, "Content-Type for this part of a DAP4 data response must be " + content_type + ".");
                }
                else if (name == "content-description") {
                        cd = true;
                        if (get_description_type(value) != object_type)
                                throw Error("Content-Description '" + value + "' not the expected value (expected: " + descrip[object_type] + ").");
                }
                else if (name == "content-id") {
                        ci = true;
                        if (!cid.empty() && value != cid)
                                throw Error("Content-Id mismatch. Expected: " + cid + ", but got: " + value);
                }
 
                header = get_next_mime_header(in);
        }
 
        if (!(ct && cd && ci)) throw Error(internal_error, "The DAP4 data response document is broken - missing header.");
}
 
string cid_to_header_value(const string &cid)
{
    string::size_type offset = cid.find("cid:");
    if (offset != 0)
        throw Error(internal_error, "expected CID to start with 'cid:'");
 
    string value = "<";
    value.append(cid.substr(offset + 4));
    value.append(">");
    downcase(value);
 
    return value;
}
 
void
set_mime_error(FILE *out, int code, const string &reason,
               const string &version)
{
    ostringstream oss;
    set_mime_error(oss, code, reason, version);
    fwrite(oss.str().data(), 1, oss.str().length(), out);
}
 
void
set_mime_error(ostream &strm, int code, const string &reason,
               const string &version)
{
    strm << "HTTP/1.0 " << code << " " << reason.c_str() << CRLF ;
    if (version == "") {
        strm << "XDODS-Server: " << DVR << CRLF ;
        strm << "XOPeNDAP-Server: " << DVR << CRLF ;
    }
    else {
        strm << "XDODS-Server: " << version.c_str() << CRLF ;
        strm << "XOPeNDAP-Server: " << version.c_str() << CRLF ;
    }
    strm << "XDAP: " << DAP_PROTOCOL_VERSION << CRLF ;
 
    const time_t t = time(0);
    strm << "Date: " << rfc822_date(t).c_str() << CRLF ;
    strm << "Cache-Control: no-cache" << CRLF ;
    strm << CRLF ;
}
 
void
set_mime_not_modified(FILE *out)
{
    ostringstream oss;
    set_mime_not_modified(oss);
    fwrite(oss.str().data(), 1, oss.str().length(), out);
}
 
void
set_mime_not_modified(ostream &strm)
{
    strm << "HTTP/1.0 304 NOT MODIFIED" << CRLF ;
    const time_t t = time(0);
    strm << "Date: " << rfc822_date(t).c_str() << CRLF ;
    strm << CRLF ;
}
 
#if 0
 
// This was removed because it's not being used by our server.
 
bool
found_override(string name, string &doc)
{
    ifstream ifs((name + ".ovr").c_str());
    if (!ifs)
        return false;
 
    char tmp[256];
    doc = "";
    while (!ifs.eof()) {
        ifs.getline(tmp, 255);
        tmp[255] = '\0';
        strncat(tmp, "\n", sizeof(tmp) - strlen(tmp) - 1);
        doc += tmp;
    }
 
        ifs.close();
    return true;
}
#endif
 
bool
remove_mime_header(FILE *in)
{
    char tmp[256];
    while (!feof(in)) {
        char *s = fgets(tmp, 255, in);
        if (s && strncmp(s, CRLF, 2) == 0)
            return true;
    }
 
    return false;
}
 
void
remove_mime_header(istream &in)
{
        while(!get_next_mime_header(in).empty()) ;
#if 0
        string header;
        do {
                header = get_next_mime_header(in);
        } while (!header.empty());
#endif
}
 
} // namespace libdap