cdlmisc.cxx

eCos1.31版

//{{{  Banner                                                   

//============================================================================
//
//      cdlmisc.cxx
//
//      Implementation of the various CDL utility member functions.
//
//============================================================================
//####COPYRIGHTBEGIN####
//                                                                          
// ----------------------------------------------------------------------------
// Copyright (C) 1998, 1999, 2000 Red Hat, Inc.
//
// This file is part of the eCos host tools.
//
// This program is free software; you can redistribute it and/or modify it 
// under the terms of the GNU General Public License as published by the Free 
// Software Foundation; either version 2 of the License, or (at your option) 
// any later version.
// 
// This program is distributed in the hope that it will be useful, but WITHOUT 
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for 
// more details.
// 
// You should have received a copy of the GNU General Public License along with
// this program; if not, write to the Free Software Foundation, Inc., 
// 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
//
// ----------------------------------------------------------------------------
//                                                                          
//####COPYRIGHTEND####
//============================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):   bartv
// Contact(s):  bartv
// Date:        1998/03/04
// Version:     0.01
//
//####DESCRIPTIONEND####
//============================================================================

//}}}
//{{{  #include's                                               

// ----------------------------------------------------------------------------
#include "cdlconfig.h"

// Get the infrastructure types, assertions, tracing and similar
// facilities.
#include <cyg/infra/cyg_ass.h>
#include <cyg/infra/cyg_trac.h>

// <cdlcore.hxx> defines everything implemented in this module.
// It implicitly supplies <string>, <vector> and <map> because
// the class definitions rely on these headers.
#include <cdlcore.hxx>

// For access to the isdigit(), isupper(), tolower(), ... functions
#include <cctype>

// For access to sprintf(), specifically double to string conversions.
#include <cstdio>

// For access to strtod()
#include <cstdlib>

// strtod() involves errno...
#include <cerrno>

// For access to fmod()
#include <cmath>

// For access to DBL_DIG
#include <cfloat>

//}}}

//{{{  Cdl::is_valid_xxx()                                      

// ---------------------------------------------------------------------------

bool
Cdl::is_valid_value_flavor(CdlValueFlavor data)
{
    bool result = false;

    switch(data) {
      case CdlValueFlavor_None     :
      case CdlValueFlavor_Bool     :
      case CdlValueFlavor_BoolData :
      case CdlValueFlavor_Data     :
        result = true;
        break;

      default:
        break;
    }

    return result;
}

bool
Cdl::is_valid_value_source(CdlValueSource data)
{
    bool result = false;

    switch(data) {
      case CdlValueSource_Default         :
      case CdlValueSource_User            :
      case CdlValueSource_Wizard          :
      case CdlValueSource_Inferred        :
        result = true;
        break;

      default:
        break;
    }

    return result;
}

// ----------------------------------------------------------------------------
// For now CDL names are restricted to what is acceptable to the C
// preprocessor. This may cause problems in future, e.g. i18n.

bool
Cdl::is_valid_cdl_name(const std::string& name)
{
    CYG_REPORT_FUNCNAMETYPE("Cdl::is_valid_cdl_name", "result %d");

    bool result = is_valid_c_preprocessor_symbol(name);
    
    CYG_REPORT_RETVAL(result);
    return result;
}

bool
Cdl::is_valid_c_preprocessor_symbol(const std::string& symbol)
{
    CYG_REPORT_FUNCNAMETYPE("Cdl::is_valid_c_preprocessor_symbol", "result %d");

    bool result = true;
    if ("" == symbol) {
        result = false;
    } else {
        // A valid preprocessor symbol should begin with either an underscore
        // or a letter. It should then be followed by some number of underscores,
        // letters, or digits.
        //
        // In some locales isalpha() may succeed for characters which are not
        // legal for C preprocessor symbols. Instead ASCII is assumed here.
        if (('_' != symbol[0]) &&
            !(('a' <= symbol[0]) && (symbol[0] <= 'z')) &&
            !(('A' <= symbol[0]) && (symbol[0] <= 'Z'))) {
            
            result = false;
        } else {
            for (unsigned int i = 1; i < symbol.size(); i++) {
                if (('_' != symbol[i]) &&
                    !(('a' <= symbol[i]) && (symbol[i] <= 'z')) &&
                    !(('A' <= symbol[i]) && (symbol[i] <= 'Z')) &&
                    !(('0' <= symbol[i]) && (symbol[i] <= '9'))) {
                    
                    result = false;
                    break;
                }
            }
        }
    }

    CYG_REPORT_RETVAL(result);
    return result;
}

//}}}
//{{{  Cdl::xxx_to_yyy() - strings, ints, doubles, ...          

// ---------------------------------------------------------------------------
// Conversion routines between strings, integers, doubles, bools, ...
//
// Conversions to/from integers are complicated somewhat because the
// data type in question is cdl_int. In the initial implementation this
// is 64 bits. In the long term it will be arbitrary precision and
// the conversion routines will need to be reimplemented.
//
// ASCII rather than EBCDIC is assumed.
//
// Some of the routines may fail, e.g. string to integer conversions.
// Others are guaranteed to succeed. 

//{{{  string_to_integer()                      

// ----------------------------------------------------------------------------
bool
Cdl::string_to_integer(std::string data, cdl_int& target)
{
    CYG_REPORT_FUNCNAMETYPE("Cdl::string_to_integer", "success %d");

    bool negative       = false;
    // Life is a bit easier if I can check for '\0'
    const char* ptr           = data.c_str();

    // Not essential but harmless.
    while (isspace(*ptr))
        ptr++;

    if ('-' == *ptr) {
        negative = true;
        ptr++;
    }

    cdl_int acc = 0;
    if ('0' == *ptr) {
        // This happens sufficiently often to be worth a special case.
        if ('\0' == ptr[1]) {
            target = 0;
            CYG_REPORT_RETVAL(true);
            return true;
        }
        // Hex is always worth supporting. 
        if (('x' == ptr[1]) || ('X' == ptr[1])) {
            ptr++; ptr++;
            if (!isxdigit(*ptr)) {
                CYG_REPORT_RETVAL(false);
                return false;
            }
            while (isxdigit(*ptr)) {
                cdl_int new_acc = acc * 16;
                if (isdigit(*ptr)) {
                    new_acc += (*ptr - '0');
                } else if (('a' <= *ptr) && (*ptr <= 'f')) {
                    new_acc += (*ptr + 10 - 'a');
                } else if (('A' <= *ptr) && (*ptr <= 'F')) {
                    new_acc += (*ptr + 10 - 'A');
                } else {
                    CYG_FAIL("this platform's implementation of isxdigit() is broken");
                }
                if (new_acc < acc) {
                    CYG_REPORT_RETVAL(false);
                    return false;
                }
                acc = new_acc;
                ptr++;
            }
            if ('\0' != *ptr) {
                CYG_REPORT_RETVAL(false);
                return false;
            }
            if (negative) {
                cdl_int new_acc = 0 - acc;
                if (new_acc > 0) {
                    CYG_REPORT_RETVAL(false);
                    return false;
                } else {
                    acc = new_acc;
                }
            }
            target = acc;
            CYG_REPORT_RETVAL(true);
            return true;
        }

        // Octal? Oh well, might as well be complete.
        if (('0' <= ptr[1]) && (ptr[1] <= '7')) {
            ptr++;
            do {
                cdl_int new_acc = 8 * acc;
                new_acc += (*ptr - '0');
                if (new_acc < acc) {
                    CYG_REPORT_RETVAL(false);
                    return false;
                }
                acc = new_acc;
                ptr++;
            } while (('0' <= *ptr) && (*ptr <= '7'));
            if ('\0' != *ptr) {
                CYG_REPORT_RETVAL(false);
                return false;
            }
            if (negative) {
                cdl_int new_acc = 0 - acc;
                if (new_acc > 0) {
                    CYG_REPORT_RETVAL(false);
                    return false;
                }
                else {
                    acc = new_acc;
                }
            }
            target = acc;
            CYG_REPORT_RETVAL(true);
            return true;
        }

        // Drop through for the case of a decimal.
    }

    while(isdigit(*ptr)) {
        cdl_int new_acc = 10 * acc;
        new_acc += (*ptr - '0');
        if (new_acc < acc) {
            CYG_REPORT_RETVAL(false);
            return false;
        }
        acc = new_acc;
        ptr++;
    }
    if ('\0' != *ptr) {
        CYG_REPORT_RETVAL(false);
        return false;
    }
    if (negative) {
        cdl_int new_acc = 0 - acc;
        if (new_acc > 0) {
            CYG_REPORT_RETVAL(false);
            return false;
        } else {
            acc = new_acc;
        }
    }
    target = acc;
    CYG_REPORT_RETVAL(true);
    return true;
}

//}}}
//{{{  string_to_double()                       

// ----------------------------------------------------------------------------
// There is no point in doing this the hard way, just use standard
// library calls.
//
// There is an obvious question as to how much precision can get lost
// doing the conversion to a string. In practice this should not matter
// too much, since the expression handling code generally keeps the
// original double precision lying around to be re-used. However it may
// be desirable to keep the libcdl behaviour in synch with Tcl's
// tcl_precision variable.

bool
Cdl::string_to_double(std::string value, double& target)
{
    CYG_REPORT_FUNCNAMETYPE("Cdl::string_to_double", "success %d");

    bool        result      = true;
    const char* start_ptr   = value.c_str();
    char*       end_ptr;
    int         old_errno   = errno;
    
    errno                   = 0;
    double conv             = strtod(start_ptr, &end_ptr);
    if (0 != errno) {
        CYG_ASSERT(ERANGE == errno, "standard-compliant C library");
        result = false;
    } else if ('\0' != *end_ptr) {
        result = false;
    } else {
        target = conv;
        result = true;
    }
     
    errno = old_errno;
    CYG_REPORT_RETVAL(result);
    return result;
}

//}}}
//{{{  string_to_bool()                         

// ----------------------------------------------------------------------------
// Conversions to and from bools. The only real issue here is exactly
// what strings should be accepted as synonyms for true and false.
// It is not actually clear that these functions are useful.
bool
Cdl::string_to_bool(std::string data, bool& target)
{
    CYG_REPORT_FUNCNAMETYPE("Cdl::string_to_bool", "success %d");

    // Arguably there should be a precondition ( "" != data )
    bool result = false;

    // What is truth ?
    if (( data == "1"   ) || (data == "true") ||
        ( data == "True") || (data == "TRUE") ) {
        result = true;
        target = true;
    } else if ((data == "0"    ) || (data == "false") ||
               (data == "False") || (data == "FALSE") ) {
        result = true;
        target = false;
    }

    CYG_REPORT_RETVAL(result);
    return result;
}

//}}}

//{{{  integer_to_string()                      

// ----------------------------------------------------------------------------

std::string
Cdl::integer_to_string(cdl_int value, CdlValueFormat format)
{
    std::string result;
    Cdl::integer_to_string(value, result, format);
    return result;
}

void
Cdl::integer_to_string(cdl_int value, std::string& target, CdlValueFormat format)
{
    CYG_REPORT_FUNCNAME("Cdl::integer_to_string");
    CYG_REPORT_FUNCARG2XV((long) value, format);

    // Optimise this special case.
    if (0 == value) {
        if (CdlValueFormat_Hex == format) {
            target = "0x0";
        } else {
            target = "0";
        }
        CYG_REPORT_RETVAL(true);
        return;
    }

    // A local buffer to construct partial strings. This avoids
    // unnecessary std::string reallocation.
    // 64 bits and three bits at a time for octal numbers gives 21 digits,
    // plus spares for the leading '0' and the terminator.
    char local_buf[24];
    char *local_ptr = &(local_buf[23]);
    *local_ptr-- = '\0';
    
    if (CdlValueFormat_Hex == format) {

        // Output the data as 0x... with either 8 or 16 digits,
        // depending on the size.
        int i;
        for (i = 0; i < 8; i++) {
            int tmp = (int) (value & 0x0F);
            value   = value >> 4;
            if (tmp < 10) {
                *local_ptr-- = '0' + tmp;
            } else {
                *local_ptr-- = 'A' + (tmp - 10);
            }
        }
        // Beware of right shifts that preserve the sign bit.
        {
            int tmp1 = (value & 0x0FFFF);
            int tmp2 = ((value >> 16) & 0x0FFFF);
            value    = (tmp2 << 16) + tmp1;
        }
        if (value != 0) {
            for (i = 0; i < 8; i++) {
                int tmp = (int) (value & 0x0F);
                value   = value >> 4;
                if (tmp < 10) {
                    *local_ptr-- = '0' + tmp;
                } else {
                    *local_ptr-- = 'A' + (tmp - 10);
                }
            }
        }
        *local_ptr-- = 'x';
        *local_ptr   = '0';
        target = std::string(local_ptr);
        
    } else if (CdlValueFormat_Octal == format) {

        // Simply output the data three bits at a time, do not worry about any
        // particular width restrictions. However it is necessary to worry
        // about masking.
        cdl_int mask = 0x1FFFFFFF;
        mask = (mask << 16) | 0x0FFFF;
        mask = (mask << 16) | 0x0FFFF;

        target = "";
        while (value > 0) {
            int tmp = value & 0x07;
            value   = (value >> 3) & mask;
            *local_ptr-- = '0' + tmp;
        }
        *local_ptr = '0';
        target = std::string(local_ptr);
        
    } else {
        // A simple decimal number      
        // Switch to positive arithmetic.
        bool negative = false;
        if (value < 0) {
            negative = true;
            value    = 0 - value;
            // Only MININT cannot be converted using the above line
            if (value < 0) {
                target = "-9223372036854775808";
                CYG_REPORT_RETVAL(true);
                return;
            }
        }

        while (value > 0) {
            int rem = (int) (value % 10);
            value   = value / 10;
            *local_ptr-- = '0' + rem;
        }
        if (negative) {
            *local_ptr-- = '-';
        }
        local_ptr++;
        target = std::string(local_ptr);
    }