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>
//
// 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 1994-1999
// Please read the full copyright statement in the file COPYRIGHT_URI.
//
// Authors:
//      jhrg,jimg       James Gallagher <jgallagher@gso.uri.edu>

// Utility functions used by the api.
//
// jhrg 9/21/94

#include "config.h"

#include <fstream>

#include <cassert>
#include <cstring>
#include <climits>
#include <cstdlib>

#include <ctype.h>
#ifndef TM_IN_SYS_TIME
#include <time.h>
#else
#include <sys/time.h>
#endif

#ifndef WIN32
#include <unistd.h>    // for stat
#else
#include <io.h>
#include <fcntl.h>
#include <process.h>
#endif

#include <sys/types.h>
#include <sys/stat.h>

#include <string>
#include <sstream>
#include <vector>
#include <algorithm>
#include <stdexcept>

#include "BaseType.h"
#include "Byte.h"
#include "Int16.h"
#include "Int32.h"
#include "UInt16.h"
#include "UInt32.h"
#include "Float32.h"
#include "Float64.h"
#include "Str.h"
#include "Array.h"

#include "Int64.h"
#include "UInt64.h"
#include "Int8.h"

#include "Error.h"

#include "util.h"
#include "GNURegex.h"
#include "debug.h"

using namespace std;

namespace libdap {

bool is_host_big_endian()
{
#ifdef COMPUTE_ENDIAN_AT_RUNTIME

    dods_int16 i = 0x0100;
    char *c = reinterpret_cast<char*>(&i);
    return *c;

#else

#if WORDS_BIGENDIAN
    return true;
#else
    return false;
#endif

#endif
}

string extract_string_argument(BaseType *arg)
{
    assert(arg);

    if (arg->type() != dods_str_c) throw Error(malformed_expr, "The function requires a string argument.");

    if (!arg->read_p())
        throw InternalErr(__FILE__, __LINE__,
                "The CE Evaluator built an argument list where some constants held no values.");

    return static_cast<Str*>(arg)->value();
}

template<class T> static void set_array_using_double_helper(Array *a, double *src, int src_len)
{
    assert(a);
    assert(src);
    assert(src_len > 0);

    vector<T> values(src_len);
    for (int i = 0; i < src_len; ++i)
        values[i] = (T) src[i];

    // This copies the values
    a->set_value(values, src_len);
}

void set_array_using_double(Array *dest, double *src, int src_len)
{
    assert(dest);
    assert(src);
    assert(src_len > 0);

    // Simple types are Byte, ..., Float64, String and Url.
    if ((dest->type() == dods_array_c && !dest->var()->is_simple_type()) || dest->var()->type() == dods_str_c
            || dest->var()->type() == dods_url_c)
        throw InternalErr(__FILE__, __LINE__, "The function requires a numeric-type array argument.");

    // Test sizes. Note that Array::length() takes any constraint into account
    // when it returns the length. Even if this was removed, the 'helper'
    // function this uses calls Vector::val2buf() which uses Vector::width()
    // which in turn uses length().
    if (dest->length() != src_len)
        throw InternalErr(__FILE__, __LINE__,
                "The source and destination array sizes don't match (" + long_to_string(src_len) + " versus "
                        + long_to_string(dest->length()) + ").");

    // The types of arguments that the CE Parser will build for numeric
    // constants are limited to Uint32, Int32 and Float64. See ce_expr.y.
    // Expanded to work for any numeric type so it can be used for more than
    // just arguments.
    switch (dest->var()->type()) {
    case dods_byte_c:
        set_array_using_double_helper<dods_byte>(dest, src, src_len);
        break;
    case dods_uint16_c:
        set_array_using_double_helper<dods_uint16>(dest, src, src_len);
        break;
    case dods_int16_c:
        set_array_using_double_helper<dods_int16>(dest, src, src_len);
        break;
    case dods_uint32_c:
        set_array_using_double_helper<dods_uint32>(dest, src, src_len);
        break;
    case dods_int32_c:
        set_array_using_double_helper<dods_int32>(dest, src, src_len);
        break;
    case dods_float32_c:
        set_array_using_double_helper<dods_float32>(dest, src, src_len);
        break;
    case dods_float64_c:
        set_array_using_double_helper<dods_float64>(dest, src, src_len);
        break;

        // DAP4 support
    case dods_uint8_c:
        set_array_using_double_helper<dods_byte>(dest, src, src_len);
        break;
    case dods_int8_c:
        set_array_using_double_helper<dods_int8>(dest, src, src_len);
        break;
    case dods_uint64_c:
        set_array_using_double_helper<dods_uint64>(dest, src, src_len);
        break;
    case dods_int64_c:
        set_array_using_double_helper<dods_int64>(dest, src, src_len);
        break;
    default:
        throw InternalErr(__FILE__, __LINE__,
                "The argument list built by the CE parser contained an unsupported numeric type.");
    }

    // Set the read_p property.
    dest->set_read_p(true);
}

template<class T> static double *extract_double_array_helper(Array * a)
{
    assert(a);

    int length = a->length();

    vector<T> b(length);
    a->value(&b[0]);    // Extract the values of 'a' to 'b'

    double *dest = new double[length];
    for (int i = 0; i < length; ++i)
        dest[i] = (double) b[i];

    return dest;
}

double *extract_double_array(Array * a)
{
    assert(a);

    // Simple types are Byte, ..., Float64, String and Url.
    if ((a->type() == dods_array_c && !a->var()->is_simple_type()) || a->var()->type() == dods_str_c
            || a->var()->type() == dods_url_c)
        throw Error(malformed_expr, "The function requires a DAP numeric-type array argument.");

    if (!a->read_p())
        throw InternalErr(__FILE__, __LINE__, string("The Array '") + a->name() + "'does not contain values.");

    // The types of arguments that the CE Parser will build for numeric
    // constants are limited to Uint32, Int32 and Float64. See ce_expr.y.
    // Expanded to work for any numeric type so it can be used for more than
    // just arguments.
    switch (a->var()->type()) {
    case dods_byte_c:
        return extract_double_array_helper<dods_byte>(a);
    case dods_uint16_c:
        return extract_double_array_helper<dods_uint16>(a);
    case dods_int16_c:
        return extract_double_array_helper<dods_int16>(a);
    case dods_uint32_c:
        return extract_double_array_helper<dods_uint32>(a);
    case dods_int32_c:
        return extract_double_array_helper<dods_int32>(a);
    case dods_float32_c:
        return extract_double_array_helper<dods_float32>(a);
    case dods_float64_c:
        // Should not be copying these values, just read them,
        // but older code may depend on the return of this function
        // being something that should be deleted, so leave this
        // alone. jhrg 2/24/15
        return extract_double_array_helper<dods_float64>(a);

        // Support for DAP4
    case dods_uint8_c:
        return extract_double_array_helper<dods_byte>(a);
    case dods_int8_c:
        return extract_double_array_helper<dods_int8>(a);
    case dods_uint64_c:
        return extract_double_array_helper<dods_uint64>(a);
    case dods_int64_c:
        return extract_double_array_helper<dods_int64>(a);
    default:
        throw InternalErr(__FILE__, __LINE__,
                "The argument list built by the CE parser contained an unsupported numeric type.");
    }
}

// This helper function assumes 'dest' is the correct size. This should not
// be called when the Array 'a' is a Float64, since the values are already
// in a double array!
template<class T> static void extract_double_array_helper(Array * a, vector<double> &dest)
{
    assert(a);
    assert(dest.size() == (unsigned long )a->length());

    int length = a->length();

    vector<T> b(length);
    a->value(&b[0]);    // Extract the values of 'a' to 'b'

    for (int i = 0; i < length; ++i)
        dest[i] = (double) b[i];
}

void extract_double_array(Array *a, vector<double> &dest)
{
    assert(a);

    // Simple types are Byte, ..., Float64, String and Url.
    if ((a->type() == dods_array_c && !a->var()->is_simple_type()) || a->var()->type() == dods_str_c
            || a->var()->type() == dods_url_c)
        throw Error(malformed_expr, "The function requires a DAP numeric-type array argument.");

    if (!a->read_p())
        throw InternalErr(__FILE__, __LINE__, string("The Array '") + a->name() + "' does not contain values.");

    dest.resize(a->length());

    // The types of arguments that the CE Parser will build for numeric
    // constants are limited to Uint32, Int32 and Float64. See ce_expr.y.
    // Expanded to work for any numeric type so it can be used for more than
    // just arguments.
    switch (a->var()->type()) {
    case dods_byte_c:
        return extract_double_array_helper<dods_byte>(a, dest);
    case dods_uint16_c:
        return extract_double_array_helper<dods_uint16>(a, dest);
    case dods_int16_c:
        return extract_double_array_helper<dods_int16>(a, dest);
    case dods_uint32_c:
        return extract_double_array_helper<dods_uint32>(a, dest);
    case dods_int32_c:
        return extract_double_array_helper<dods_int32>(a, dest);
    case dods_float32_c:
        return extract_double_array_helper<dods_float32>(a, dest);
    case dods_float64_c:
        return a->value(&dest[0]);      // no need to copy the values
        // return extract_double_array_helper<dods_float64>(a, dest);

        // Support for DAP4
    case dods_uint8_c:
        return extract_double_array_helper<dods_byte>(a, dest);
    case dods_int8_c:
        return extract_double_array_helper<dods_int8>(a, dest);
    case dods_uint64_c:
        return extract_double_array_helper<dods_uint64>(a, dest);
    case dods_int64_c:
        return extract_double_array_helper<dods_int64>(a, dest);
    default:
        throw InternalErr(__FILE__, __LINE__,
                "The argument list built by the CE parser contained an unsupported numeric type.");
    }
}

double extract_double_value(BaseType *arg)
{
    assert(arg);

    // Simple types are Byte, ..., Float64, String and Url.
    if (!arg->is_simple_type() || arg->type() == dods_str_c || arg->type() == dods_url_c)
        throw Error(malformed_expr, "The function requires a numeric-type argument.");

    if (!arg->read_p())
        throw InternalErr(__FILE__, __LINE__,
                "The Evaluator built an argument list where some constants held no values.");

    // The types of arguments that the CE Parser will build for numeric
    // constants are limited to Uint32, Int32 and Float64. See ce_expr.y.
    // Expanded to work for any numeric type so it can be used for more than
    // just arguments.
    switch (arg->type()) {
    case dods_byte_c:
        return (double) (static_cast<Byte*>(arg)->value());
    case dods_uint16_c:
        return (double) (static_cast<UInt16*>(arg)->value());
    case dods_int16_c:
        return (double) (static_cast<Int16*>(arg)->value());
    case dods_uint32_c:
        return (double) (static_cast<UInt32*>(arg)->value());
    case dods_int32_c:
        return (double) (static_cast<Int32*>(arg)->value());
    case dods_float32_c:
        return (double) (static_cast<Float32*>(arg)->value());
    case dods_float64_c:
        return static_cast<Float64*>(arg)->value();

        // Support for DAP4 types.
    case dods_uint8_c:
        return (double) (static_cast<Byte*>(arg)->value());
    case dods_int8_c:
        return (double) (static_cast<Int8*>(arg)->value());
    case dods_uint64_c:
        return (double) (static_cast<UInt64*>(arg)->value());
    case dods_int64_c:
        return (double) (static_cast<Int64*>(arg)->value());

    default:
        throw InternalErr(__FILE__, __LINE__,
                "The argument list built by the parser contained an unsupported numeric type.");
    }
}

// Remove spaces from the start of a URL and from the start of any constraint
// expression it contains. 4/7/98 jhrg

string prune_spaces(const string &name)
{
    // If the URL does not even have white space return.
    if (name.find_first_of(' ') == name.npos)
        return name;
    else {
        // Strip leading spaces from http://...
        unsigned int i = name.find_first_not_of(' ');
        string tmp_name = name.substr(i);

        // Strip leading spaces from constraint part (following `?').
        unsigned int j = tmp_name.find('?') + 1;
        i = tmp_name.find_first_not_of(' ', j);
        tmp_name.erase(j, i - j);

        return tmp_name;
    }
}

// Compare elements in a list of (BaseType *)s and return true if there are
// no duplicate elements, otherwise return false.

bool unique_names(vector<BaseType *> l, const string &var_name, const string &type_name, string &msg)
{
    // copy the identifier names to a vector
    vector<string> names(l.size());

    int nelem = 0;
    typedef std::vector<BaseType *>::const_iterator citer;
    for (citer i = l.begin(); i != l.end(); i++) {
        assert(*i);
        names[nelem++] = (*i)->name();
        DBG(cerr << "NAMES[" << nelem - 1 << "]=" << names[nelem-1] << endl);
    }

    // sort the array of names
    sort(names.begin(), names.end());

    // sort the array of names
    sort(names.begin(), names.end());

    // look for any instance of consecutive names that are ==
    for (int j = 1; j < nelem; ++j) {
        if (names[j - 1] == names[j]) {
            ostringstream oss;
            oss << "The variable `" << names[j] << "' is used more than once in " << type_name << " `" << var_name
                    << "'";
            msg = oss.str();

            return false;
        }
    }

    return true;
}

const char *
libdap_root()
{
    return LIBDAP_ROOT;
}

extern "C" const char *
libdap_version()
{
    return PACKAGE_VERSION;
}

extern "C" const char *
libdap_name()
{
    return PACKAGE_NAME;
}

string systime()
{
    time_t TimBin;

    if (time(&TimBin) == (time_t) -1)
        return string("time() error");
    else {
        char *ctime_value = ctime(&TimBin);
        if (ctime_value) {
            string TimStr = ctime_value;
            return TimStr.substr(0, TimStr.size() - 2); // remove the \n
        }
        else
            return "Unknown";
    }
}

void downcase(string &s)
{
    for (unsigned int i = 0; i < s.length(); i++)
        s[i] = tolower(s[i]);
}

bool is_quoted(const string &s)
{
    return (!s.empty() && s[0] == '\"' && s[s.length() - 1] == '\"');
}

string remove_quotes(const string &s)
{
    if (is_quoted(s))
        return s.substr(1, s.length() - 2);
    else
        return s;
}

Type get_type(const char *name)
{
    if (strcmp(name, "Byte") == 0) return dods_byte_c;

    if (strcmp(name, "Char") == 0) return dods_char_c;

    if (strcmp(name, "Int8") == 0) return dods_int8_c;

    if (strcmp(name, "UInt8") == 0) return dods_uint8_c;

    if (strcmp(name, "Int16") == 0) return dods_int16_c;

    if (strcmp(name, "UInt16") == 0) return dods_uint16_c;

    if (strcmp(name, "Int32") == 0) return dods_int32_c;

    if (strcmp(name, "UInt32") == 0) return dods_uint32_c;

    if (strcmp(name, "Int64") == 0) return dods_int64_c;

    if (strcmp(name, "UInt64") == 0) return dods_uint64_c;

    if (strcmp(name, "Float32") == 0) return dods_float32_c;

    if (strcmp(name, "Float64") == 0) return dods_float64_c;

    if (strcmp(name, "String") == 0) return dods_str_c;

    // accept both spellings; this might be confusing since URL
    // could be filtered through code and come out Url. Don't know...
    // jhrg 8/15/13
    if (strcmp(name, "Url") == 0 || strcmp(name, "URL") == 0) return dods_url_c;

    if (strcmp(name, "Enum") == 0) return dods_enum_c;

    if (strcmp(name, "Opaque") == 0) return dods_opaque_c;

    if (strcmp(name, "Array") == 0) return dods_array_c;

    if (strcmp(name, "Structure") == 0) return dods_structure_c;

    if (strcmp(name, "Sequence") == 0) return dods_sequence_c;

    if (strcmp(name, "Grid") == 0) return dods_grid_c;

    return dods_null_c;
}

string D2type_name(Type t)
{
    switch (t) {
    case dods_null_c:
        return string("Null");
    case dods_byte_c:
        return string("Byte");
    case dods_int16_c:
        return string("Int16");
    case dods_uint16_c:
        return string("UInt16");
    case dods_int32_c:
        return string("Int32");
    case dods_uint32_c:
        return string("UInt32");
    case dods_float32_c:
        return string("Float32");
    case dods_float64_c:
        return string("Float64");
    case dods_str_c:
        return string("String");
    case dods_url_c:
        return string("Url");

    case dods_array_c:
        return string("Array");
    case dods_structure_c:
        return string("Structure");
    case dods_sequence_c:
        return string("Sequence");
    case dods_grid_c:
        return string("Grid");

    default:
        throw InternalErr(__FILE__, __LINE__, "Unknown type.");
    }
}

string D4type_name(Type t)
{
    switch (t) {
    case dods_null_c:
        return string("Null");
    case dods_byte_c:
        return string("Byte");
    case dods_char_c:
        return string("Char");
    case dods_int8_c:
        return string("Int8");
    case dods_uint8_c:
        return string("UInt8");
    case dods_int16_c:
        return string("Int16");
    case dods_uint16_c:
        return string("UInt16");
    case dods_int32_c:
        return string("Int32");
    case dods_uint32_c:
        return string("UInt32");
    case dods_int64_c:
        return string("Int64");
    case dods_uint64_c:
        return string("UInt64");
    case dods_enum_c:
        return string("Enum");

    case dods_float32_c:
        return string("Float32");
    case dods_float64_c:
        return string("Float64");

    case dods_str_c:
        return string("String");
    case dods_url_c:
        return string("URL");

    case dods_opaque_c:
        return string("Opaque");

    case dods_array_c:
        return string("Array");

    case dods_structure_c:
        return string("Structure");
    case dods_sequence_c:
        return string("Sequence");
    case dods_group_c:
        return string("Group");

    default:
        throw InternalErr(__FILE__, __LINE__, "Unknown type.");
    }
}

string type_name(Type t)
{
    try {
        return D4type_name(t);
    }
    catch (...) {
        return D2type_name(t);
    }
}

bool is_simple_type(Type t)
{
    switch (t) {

    case dods_byte_c:
    case dods_char_c:

    case dods_int8_c:
    case dods_uint8_c:

    case dods_int16_c:
    case dods_uint16_c:
    case dods_int32_c:
    case dods_uint32_c:

    case dods_int64_c:
    case dods_uint64_c:

    case dods_float32_c:
    case dods_float64_c:
    case dods_str_c:
    case dods_url_c:
    case dods_enum_c:
    case dods_opaque_c:
        return true;

    case dods_null_c:
    case dods_array_c:
    case dods_structure_c:
    case dods_sequence_c:
    case dods_grid_c:
    case dods_group_c:
    default:
        return false;
    }
}

bool is_vector_type(Type t)
{
    switch (t) {
    case dods_null_c:
    case dods_byte_c:
    case dods_char_c:

    case dods_int8_c:
    case dods_uint8_c:

    case dods_int16_c:
    case dods_uint16_c:

    case dods_int32_c:
    case dods_uint32_c:

    case dods_int64_c:
    case dods_uint64_c:

    case dods_float32_c:
    case dods_float64_c:

    case dods_str_c:
    case dods_url_c:
    case dods_enum_c:
    case dods_opaque_c:
        return false;

    case dods_array_c:
        return true;

    case dods_structure_c:
    case dods_sequence_c:
    case dods_grid_c:
    case dods_group_c:
    default:
        return false;
    }
}

bool is_constructor_type(Type t)
{
    switch (t) {
    case dods_null_c:
    case dods_byte_c:
    case dods_char_c:

    case dods_int8_c:
    case dods_uint8_c:

    case dods_int16_c:
    case dods_uint16_c:
    case dods_int32_c:
    case dods_uint32_c:

    case dods_int64_c:
    case dods_uint64_c:

    case dods_float32_c:
    case dods_float64_c:
    case dods_str_c:
    case dods_url_c:
    case dods_enum_c:
    case dods_opaque_c:

    case dods_array_c:
        return false;

    case dods_structure_c:
    case dods_sequence_c:
    case dods_grid_c:
    case dods_group_c:
    default:
        return true;
    }
}

bool is_integer_type(Type t)
{
    switch (t) {
    case dods_byte_c:
    case dods_char_c:
    case dods_int8_c:
    case dods_uint8_c:
    case dods_int16_c:
    case dods_uint16_c:
    case dods_int32_c:
    case dods_uint32_c:
    case dods_int64_c:
    case dods_uint64_c:
        return true;
    default:
        return false;
    }
}

bool dir_exists(const string &dir)
{
    struct stat buf;

    return (stat(dir.c_str(), &buf) == 0) && (buf.st_mode & S_IFDIR);
}

// Jose Garcia
void append_long_to_string(long val, int base, string &str_val)
{
    // The array digits contains 36 elements which are the
    // posible valid digits for out bases in the range
    // [2,36]
    char digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    // result of val / base
    ldiv_t r;

    if (base > 36 || base < 2) {
        // no conversion if wrong base
        std::invalid_argument ex("The parameter base has an invalid value.");
        throw ex;
    }
    if (val < 0) str_val += '-';
    r = ldiv(labs(val), base);

    // output digits of val/base first
    if (r.quot > 0) append_long_to_string(r.quot, base, str_val);

    // output last digit

    str_val += digits[(int) r.rem];
}

// base defaults to 10
string long_to_string(long val, int base)
{
    string s;
    append_long_to_string(val, base, s);
    return s;
}

// Jose Garcia
void append_double_to_string(const double &num, string &str)
{
    // s having 100 characters should be enough for sprintf to do its job.
    // I want to banish all instances of sprintf. 10/5/2001 jhrg
    ostringstream oss;
    oss.precision(9);
    oss << num;
    str += oss.str();
}

string double_to_string(const double &num)
{
    string s;
    append_double_to_string(num, s);
    return s;
}

// Given a pathname, return the file at the end of the path. This is used
// when reporting errors (maybe other times, too) to keep the server from
// revealing too much about its organization when sending error responses
// back to clients. 10/11/2000 jhrg
// MT-safe. 08/05/02 jhrg

#ifdef WIN32
static const char path_sep[] =
{   "\\"
};
#else
static const char path_sep[] = { "/" };
#endif

string path_to_filename(string path)
{
    string::size_type pos = path.rfind(path_sep);

    return (pos == string::npos) ? path : path.substr(++pos);
}

#define CHECK_BIT( tab, bit ) ( tab[ (bit)/8 ] & (1<<( (bit)%8 )) )
#define BITLISTSIZE 16 /* bytes used for [chars] in compiled expr */

/*
 * globchars() - build a bitlist to check for character group match
 */

static void globchars(const char *s, const char *e, char *b)
{
    int neg = 0;

    memset(b, '\0', BITLISTSIZE);

    if (*s == '^') neg++, s++;

    while (s < e) {
        int c;

        if (s + 2 < e && s[1] == '-') {
            for (c = s[0]; c <= s[2]; c++)
                b[c / 8] |= (1 << (c % 8));
            s += 3;
        }
        else {
            c = *s++;
            b[c / 8] |= (1 << (c % 8));
        }
    }

    if (neg) {
        int i;
        for (i = 0; i < BITLISTSIZE; i++)
            b[i] ^= 0377;
    }

    /* Don't include \0 in either $[chars] or $[^chars] */

    b[0] &= 0376;
}

int glob(const char *c, const char *s)
{
    if (!c || !s) return 1;

    char bitlist[BITLISTSIZE];
    int i = 0;
    for (;;) {
        ++i;
        switch (*c++) {
        case '\0':
            return *s ? -1 : 0;

        case '?':
            if (!*s++) return i/*1*/;
            break;

        case '[': {
            /* scan for matching ] */

            const char *here = c;
            do {
                if (!*c++) return i/*1*/;
            } while (here == c || *c != ']');
            c++;

            /* build character class bitlist */

            globchars(here, c, bitlist);

            if (!CHECK_BIT(bitlist, *(unsigned char * )s)) return i/*1*/;
            s++;
            break;
        }

        case '*': {
            const char *here = s;

            while (*s)
                s++;

            /* Try to match the rest of the pattern in a recursive */
            /* call.  If the match fails we'll back up chars, retrying. */

            while (s != here) {
                int r;

                /* A fast path for the last token in a pattern */

                r = *c ? glob(c, s) : *s ? -1 : 0;

                if (!r)
                    return 0;
                else if (r < 0) return i/*1*/;

                --s;
            }
            break;
        }

        case '\\':
            /* Force literal match of next char. */

            if (!*c || *s++ != *c++) return i/*1*/;
            break;

        default:
            if (*s++ != c[-1]) return i/*1*/;
            break;
        }
    }
}

bool size_ok(unsigned int sz, unsigned int nelem)
{
    return (sz > 0 && nelem < UINT_MAX / sz);
}

bool pathname_ok(const string &path, bool strict)
{
    if (path.length() > 255) return false;

    Regex name("[-0-9A-z_./]+");
    if (!strict) name = "[:print:]+";

    string::size_type len = path.length();
    int result = name.match(path.c_str(), len);
    // Protect against casting too big an uint to int
    // if LEN is bigger than the max int32, the second test can't work
    if (len > INT_MAX || result != static_cast<int>(len)) return false;

    return true;
}


string dap_version()
{
    return (string) "OPeNDAP DAP/" + libdap_version() + ": compiled on " + __DATE__ + ":" + __TIME__;
}

string open_temp_fstream(ofstream &f, const string &name_template, const string &suffix /* = "" */)
{
    vector<char> name;
    copy(name_template.begin(), name_template.end(), back_inserter(name));
    if (!suffix.empty())
        copy(suffix.begin(), suffix.end(), back_inserter(name));
    name.push_back('\0');

    // Use mkstemp to make and open the temp file atomically
    int tmpfile = mkstemps(&name[0], suffix.length());
    if (tmpfile == -1)
        throw Error(internal_error, "Could not make a temporary file.");
    // Open the file using C++ ofstream; get a C++ fstream object
    f.open(&name[0]);
    // Close the file descriptor; the file stays open because of the fstream object
    close(tmpfile);
    // Now test that the fstream object is valid
    if (f.fail())
        throw Error(internal_error, "Could not make a temporary file.");

    return string(&name[0]);
}


} // namespace libdap