smbios.cpp

Go to the documentation of this file.

/* Copyright (c) 2011 Wildfire Games
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/*
 * provide access to System Management BIOS information
 */

#include "precompiled.h"
#include "lib/sysdep/smbios.h"

#include "lib/bits.h"
#include "lib/alignment.h"
#include "lib/byte_order.h" // FOURCC_BE
#include "lib/module_init.h"

#if OS_WIN
# include "lib/sysdep/os/win/wutil.h"
# include "lib/sysdep/os/win/wfirmware.h"
#endif

#include <sstream>

namespace SMBIOS {

//-----------------------------------------------------------------------------
// GetTable

#if OS_WIN

static Status GetTable(wfirmware::Table& table)
{
    // (MSDN mentions 'RSMB', but multi-character literals are implementation-defined.)
    const DWORD provider = FOURCC_BE('R','S','M','B');

    // (MSDN says this will be 0, but we'll retrieve it for 100% correctness.)
    wfirmware::TableIds tableIds = wfirmware::GetTableIDs(provider);
    if(tableIds.empty())
        return ERR::_1; // NOWARN (happens on 32-bit XP)

    table = wfirmware::GetTable(provider, tableIds[0]);
    if(table.empty())
        WARN_RETURN(ERR::_2);

    // strip the WmiHeader
    struct WmiHeader
    {
        u8 used20CallingMethod;
        u8 majorVersion;
        u8 minorVersion;
        u8 dmiRevision;
        u32 length;
    };
    const WmiHeader* wmiHeader = (const WmiHeader*)&table[0];
    ENSURE(table.size() == sizeof(WmiHeader) + wmiHeader->length);
    memmove(&table[0], &table[sizeof(WmiHeader)], table.size()-sizeof(WmiHeader));

    return INFO::OK;
}

#endif  // OS_WIN


//-----------------------------------------------------------------------------
// strings

// pointers to the strings (if any) at the end of an SMBIOS structure
typedef std::vector<const char*> Strings;

static Strings ExtractStrings(const Header* header, const char* end, const Header*& next)
{
    Strings strings;

    const char* pos = ((const char*)header) + header->length;
    while(pos <= end-2)
    {
        if(*pos == '\0')
        {
            pos++;
            if(*pos == 0)
            {
                pos++;
                break;
            }
        }

        strings.push_back(pos);
        pos += strlen(pos);
    }

    next = (const Header*)pos;
    return strings;
}


// storage for all structures' strings (must be copied from the original
// wfirmware table since its std::vector container cannot be stored in a
// static variable because we may be called before _cinit)
static char* stringStorage;
static char* stringStoragePos;

// pointers to dynamically allocated structures
static Structures structures;

static void Cleanup()   // called via atexit
{
    SAFE_FREE(stringStorage);
    stringStoragePos = 0;

    // free each allocated structure
#define STRUCTURE(name, id)\
    while(structures.name##_)\
    {\
        name* next = structures.name##_->next;\
        SAFE_FREE(structures.name##_);\
        structures.name##_ = next;\
    }
    STRUCTURES
#undef STRUCTURE
}


//-----------------------------------------------------------------------------
// FieldInitializer

// define function templates that invoke a Visitor for each of a structure's fields
#define FIELD(flags, type, name, units) visitor(flags, p.name, #name, units);
#define STRUCTURE(name, id) template<class Visitor> void VisitFields(name& p, Visitor& visitor) { name##_FIELDS }
STRUCTURES
#undef STRUCTURE
#undef FIELD


// initialize each of a structure's fields by copying from the SMBIOS data
class FieldInitializer
{
    NONCOPYABLE(FieldInitializer);  // reference member
public:
    FieldInitializer(const Header* header, const Strings& strings)
        : data((const u8*)(header+1))
        , end((const u8*)header + header->length)
        , strings(strings)
    {
    }

    template<typename Field>
    void operator()(size_t flags, Field& field, const char* UNUSED(name), const char* UNUSED(units))
    {
        if((flags & F_DERIVED) || data >= end)
        {
            field = Field();
            return;
        }

        Read(field, 0); // SFINAE
    }

private:
    template<typename T>
    T ReadValue()
    {
        T value;
        memcpy(&value, data, sizeof(value));
        data += sizeof(value);
        return value;
    }

    // construct from SMBIOS representations that don't match the
    // actual type (e.g. enum)
    template<typename Field>
    void Read(Field& field, typename Field::T*)
    {
        field = Field(ReadValue<typename Field::T>());
    }

    template<typename Field>
    void Read(Field& field, ...)
    {
        field = ReadValue<Field>();
    }

    const u8* data;
    const u8* end;
    const Strings& strings;
};


// C++03 14.7.3(2): "An explicit specialization shall be declared [..] in the
// namespace of which the enclosing class [..] is a member.

// (this specialization avoids a "forcing value to bool true or false" warning)
template<>
void FieldInitializer::operator()<bool>(size_t flags, bool& UNUSED(t), const char* UNUSED(name), const char* UNUSED(units))
{
    // SMBIOS doesn't specify any individual booleans, so we're only called for
    // derived fields and don't need to do anything.
    ENSURE(flags & F_DERIVED);
}

template<>
void FieldInitializer::operator()<const char*>(size_t flags, const char*& t, const char* UNUSED(name), const char* UNUSED(units))
{
    t = 0;  // (allow immediate `return' when the string is found to be invalid)

    u8 number;
    operator()(flags, number, 0, 0);
    if(number == 0) // no string given
        return;

    if(number > strings.size())
    {
        debug_printf(L"SMBIOS: invalid string number %d (count=%d)\n", number, (int)strings.size());
        return;
    }

    // copy to stringStorage
    strcpy(stringStoragePos, strings[number-1]);
    t = stringStoragePos;
    stringStoragePos += strlen(t)+1;
}


//-----------------------------------------------------------------------------
// Fixup (e.g. compute derived fields)

template<class Structure>
void Fixup(Structure& UNUSED(structure))
{
    // primary template: do nothing
}

template<>
void Fixup<Bios>(Bios& p)
{
    p.size = size_t(p.encodedSize+1) * 64*KiB;
}

template<>
void Fixup<Processor>(Processor& p)
{
    p.populated = (p.status & 0x40) != 0;
    p.status = (ProcessorStatus)bits(p.status, 0, 2);

    if(p.voltage & 0x80)
        p.voltage &= ~0x80;
    else
    {
        // (arbitrarily) report the lowest supported value
        if(IsBitSet(p.voltage, 0))
            p.voltage = 50;
        if(IsBitSet(p.voltage, 1))
            p.voltage = 33;
        if(IsBitSet(p.voltage, 2))
            p.voltage = 29;
    }
}

template<>
void Fixup<Cache>(Cache& p)
{
    struct DecodeSize
    {
        u64 operator()(u16 size) const
        {
            const size_t granularity = IsBitSet(size, 15)? 64*KiB : 1*KiB;
            return u64(bits(size, 0, 14)) * granularity;
        }
    };
    p.maxSize = DecodeSize()(p.maxSize16);
    p.installedSize = DecodeSize()(p.installedSize16);
    p.level = bits(p.configuration, 0, 2)+1;
    p.location = (CacheLocation)bits(p.configuration, 5, 6);
    p.mode = (CacheMode)bits(p.configuration, 8, 9);
    p.configuration = (CacheConfigurationFlags)(p.configuration & ~0x367);
}

template<>
void Fixup<SystemSlot>(SystemSlot& p)
{
    // (only initialize function and device numbers if functionAndDeviceNumber is valid)
    if(p.functionAndDeviceNumber != 0xFF)
    {
        p.functionNumber = bits(p.functionAndDeviceNumber, 0, 2);
        p.deviceNumber = bits(p.functionAndDeviceNumber, 3, 7);
    }
}

template<>
void Fixup<OnBoardDevices>(OnBoardDevices& p)
{
    p.enabled = (p.type.value & 0x80) != 0;
    p.type = (OnBoardDeviceType)(p.type & ~0x80);
}

template<>
void Fixup<MemoryArray>(MemoryArray& p)
{
    if(p.maxCapacity32 != (u32)INT32_MIN)
        p.maxCapacity = u64(p.maxCapacity32) * KiB;
}

template<>
void Fixup<MemoryDevice>(MemoryDevice& p)
{
    if(p.size16 != INT16_MAX)
        p.size = u64(bits(p.size16, 0, 14)) * (IsBitSet(p.size16, 15)? 1*KiB : 1*MiB);
    else
        p.size = u64(bits(p.size32, 0, 30)) * MiB;
    p.rank = bits(p.attributes, 0, 3);
}

template<>
void Fixup<MemoryArrayMappedAddress>(MemoryArrayMappedAddress& p)
{
    if(p.startAddress32 != UINT32_MAX)
        p.startAddress = u64(p.startAddress32) * KiB;
    if(p.endAddress32 != UINT32_MAX)
        p.endAddress = u64(p.endAddress32) * KiB;
}

template<>
void Fixup<MemoryDeviceMappedAddress>(MemoryDeviceMappedAddress& p)
{
    if(p.startAddress32 != UINT32_MAX)
        p.startAddress = u64(p.startAddress32) * KiB;
    if(p.endAddress32 != UINT32_MAX)
        p.endAddress = u64(p.endAddress32) * KiB;
}

template<>
void Fixup<VoltageProbe>(VoltageProbe& p)
{
    p.location = (VoltageProbeLocation)bits(p.locationAndStatus, 0, 4);
    p.status = (State)bits(p.locationAndStatus, 5, 7);
}

template<>
void Fixup<CoolingDevice>(CoolingDevice& p)
{
    p.type = (CoolingDeviceType)bits(p.typeAndStatus, 0, 4);
    p.status = (State)bits(p.typeAndStatus, 5, 7);
}

template<>
void Fixup<TemperatureProbe>(TemperatureProbe& p)
{
    p.location = (TemperatureProbeLocation)bits(p.locationAndStatus, 0, 4);
    p.status = (State)bits(p.locationAndStatus, 5, 7);
}

template<>
void Fixup<SystemPowerSupply>(SystemPowerSupply& p)
{
    p.type = (SystemPowerSupplyType)bits(p.characteristics, 10, 13);
    p.status = (State)bits(p.characteristics, 7, 9);
    p.inputSwitching = (SystemPowerSupplyInputSwitching)bits(p.characteristics, 3, 6);
    p.characteristics = bits(p.characteristics, 0, 2);
}

template<>
void Fixup<OnboardDevices2>(OnboardDevices2& p)
{
    p.enabled = IsBitSet(p.type, 7);
    p.type = (OnBoardDeviceType)bits(p.type, 0, 6);
    p.deviceNumber = bits(p.functionAndDeviceNumber, 3, 7);
    p.functionNumber = bits(p.functionAndDeviceNumber, 0, 2);
}


//-----------------------------------------------------------------------------
// InitStructures

template<class Structure>
void AddStructure(const Header* header, const Strings& strings, Structure*& listHead)
{
    Structure* const p = (Structure*)calloc(1, sizeof(Structure));  // freed in Cleanup
    p->header = *header;

    if(listHead)
    {
        // insert at end of list to preserve order of caches/slots
        Structure* last = listHead;
        while(last->next)
            last = last->next;
        last->next = p;
    }
    else
        listHead = p;

    FieldInitializer fieldInitializer(header, strings);
    VisitFields(*p, fieldInitializer);

    Fixup(*p);
}


static Status InitStructures()
{
#if OS_WIN
    wfirmware::Table table;
    RETURN_STATUS_IF_ERR(GetTable(table));
#else
    std::vector<u8> table;
    return ERR::NOT_SUPPORTED;
#endif

    // (instead of counting the total string size, just use the
    // SMBIOS size - typically 1-2 KB - as an upper bound.)
    stringStoragePos = stringStorage = (char*)calloc(table.size(), sizeof(char));   // freed in Cleanup
    if(!stringStorage)
        WARN_RETURN(ERR::NO_MEM);

    atexit(Cleanup);

    const Header* header = (const Header*)&table[0];
    const Header* const end = (const Header*)(&table[0] + table.size());
    for(;;)
    {
        if(header+1 > end)
        {
            debug_printf(L"SMBIOS: table not terminated\n");
            break;
        }
        if(header->id == 127)   // end
            break;
        if(header->length < sizeof(Header))
            WARN_RETURN(ERR::_3);

        const Header* next;
        const Strings strings = ExtractStrings(header, (const char*)end, next);

        switch(header->id)
        {
#define STRUCTURE(name, id) case id: AddStructure(header, strings, structures.name##_); break;
            STRUCTURES
#undef STRUCTURE

        default:
            if(32 < header->id && header->id < 126) // only mention non-proprietary structures of which we are not aware
                debug_printf(L"SMBIOS: unknown structure type %d\n", header->id);
            break;
        }

        header = next;
    }

    return INFO::OK;
}


//-----------------------------------------------------------------------------
// StringFromEnum

template<class Enum>
std::string StringFromEnum(Enum UNUSED(field))
{
    return "(unknown enumeration)";
}

#define ENUM(enumerator, VALUE)\
    if(field.value == VALUE) /* single bit flag or matching enumerator */\
        return #enumerator;\
    if(!is_pow2(VALUE)) /* these aren't bit flags */\
    {\
        allowFlags = false;\
        string.clear();\
    }\
    if(allowFlags && (field.value & (VALUE)))\
    {\
        if(!string.empty())\
            string += "|";\
        string += #enumerator;\
    }
#define ENUMERATION(name, type)\
    template<>\
    std::string StringFromEnum<name>(name field)\
    {\
        std::string string;\
        bool allowFlags = true;\
        name##_ENUMERATORS\
        /* (don't warn about the value 0, e.g. optional fields) */\
        if(string.empty() && field != 0)\
        {\
            std::stringstream ss;\
            ss << "(unknown " << #name << " " << field.value << ")";\
            return ss.str();\
        }\
        return string;\
    }
ENUMERATIONS
#undef ENUMERATION
#undef ENUM


//-----------------------------------------------------------------------------
// FieldStringizer

class FieldStringizer
{
    NONCOPYABLE(FieldStringizer);   // reference member
public:
    FieldStringizer(std::stringstream& ss)
        : ss(ss)
    {
    }

    template<typename Field>
    void operator()(size_t flags, Field& field, const char* name, const char* units)
    {
        if(flags & F_INTERNAL)
            return;

        Write(flags, field, name, units, 0);    // SFINAE
    }

    // special case for sizes [bytes]
    template<typename T>
    void operator()(size_t flags, Size<T>& size, const char* name, const char* units)
    {
        if(flags & F_INTERNAL)
            return;

        const u64 value = (u64)size.value;
        if(value == 0)
            return;

        u64 divisor;
        if(value > GiB)
        {
            divisor = GiB;
            units = " GiB";
        }
        else if(value > MiB)
        {
            divisor = MiB;
            units = " MiB";
        }
        else if(value > KiB)
        {
            divisor = KiB;
            units = " KiB";
        }
        else
        {
            divisor = 1;
            units = " bytes";
        }

        WriteName(name);

        // (avoid floating-point output unless division would truncate the value)
        if(value % divisor == 0)
            ss << (value/divisor);
        else
            ss << (double(value)/divisor);

        WriteUnits(units);
    }

private:
    void WriteName(const char* name)
    {
        ss << "  "; // indent
        ss << name << ": ";
    }

    void WriteUnits(const char* units)
    {
        ss << units;
        ss << "\n";
    }

    // enumerations and bit flags
    template<typename Field>
    void Write(size_t UNUSED(flags), Field& field, const char* name, const char* units, typename Field::Enum*)
    {
        // 0 usually means "not included in structure", but some packed
        // enumerations actually use that value. therefore, only skip this
        // field if it is zero AND no matching enumerator is found.
        const std::string string = StringFromEnum(field);
        if(string.empty())
            return;

        WriteName(name);
        ss << StringFromEnum(field);
        WriteUnits(units);
    }

    // all other field types
    template<typename Field>
    void Write(size_t flags, Field& field, const char* name, const char* units, ...)
    {
        // SMBIOS uses the smallest and sometimes also largest representable
        // signed/unsigned value to indicate `unknown' (except enumerators -
        // but those are handled in the other function overload), so skip them.
        if(field == std::numeric_limits<Field>::min() || field == std::numeric_limits<Field>::max())
            return;

        WriteName(name);

        if(flags & F_HEX)
            ss << std::hex << std::uppercase;

        if(sizeof(field) == 1)  // avoid printing as a character
            ss << unsigned(field);
        else
            ss << field;

        if(flags & F_HEX)
            ss << std::dec; // (revert to decimal, e.g. for displaying sizes)

        WriteUnits(units);
    }

    std::stringstream& ss;
};

template<>
void FieldStringizer::operator()<bool>(size_t flags, bool& value, const char* name, const char* units)
{
    if(flags & F_INTERNAL)
        return;

    WriteName(name);
    ss << (value? "true" : "false");
    WriteUnits(units);
}

template<>
void FieldStringizer::operator()<Handle>(size_t flags, Handle& handle, const char* name, const char* units)
{
    if(flags & F_INTERNAL)
        return;

    // don't display useless handles
    if(handle.value == 0 || handle.value == 0xFFFE || handle.value == 0xFFFF)
        return;

    WriteName(name);
    ss << handle.value;
    WriteUnits(units);
}


template<>
void FieldStringizer::operator()<const char*>(size_t flags, const char*& value, const char* name, const char* units)
{
    if(flags & F_INTERNAL)
        return;

    // don't display useless strings
    if(value == 0)
        return;
    std::string string(value);
    const size_t lastChar = string.find_last_not_of(' ');
    if(lastChar == std::string::npos)   // nothing but spaces
        return;
    string.resize(lastChar+1);  // strip trailing spaces
    if(!strcasecmp(value, "To Be Filled By O.E.M."))
        return;

    WriteName(name);
    ss << "\"" << string << "\"";
    WriteUnits(units);
}


//-----------------------------------------------------------------------------
// public interface

const Structures* GetStructures()
{
    static ModuleInitState initState;
    Status ret = ModuleInit(&initState, InitStructures);
    // (callers have to check if member pointers are nonzero anyway, so
    // we always return a valid pointer to simplify most use cases.)
    UNUSED2(ret);
    return &structures;
}


template<class Structure>
void StringizeStructure(const char* name, Structure* p, std::stringstream& ss)
{
    for(; p; p = p->next)
    {
        ss << "\n[" << name << "]\n";
        FieldStringizer fieldStringizer(ss);
        VisitFields(*p, fieldStringizer);
    }
}

std::string StringizeStructures(const Structures* structures)
{
    std::stringstream ss;
#define STRUCTURE(name, id) StringizeStructure(#name, structures->name##_, ss);
    STRUCTURES
#undef STRUCTURE

    return ss.str();
}

}   // namespace SMBIOS