cper-utils.c

/**
 * Describes utility functions for parsing CPER into JSON IR. 
 * 
 * Author: Lawrence.Tang@arm.com
 **/

#include <stdio.h>
#include "json.h"
#include "edk/Cper.h"
#include "cper-utils.h"

//The available severity types for CPER.
const char* CPER_SEVERITY_TYPES[4] = {"Recoverable", "Fatal", "Corrected", "Informational"};

//Converts the given generic CPER error status to JSON IR.
json_object* cper_generic_error_status_to_ir(EFI_GENERIC_ERROR_STATUS* error_status)
{
    json_object* error_status_ir = json_object_new_object();

    //Error type.
    json_object_object_add(error_status_ir, "errorType", integer_to_readable_pair_with_desc(error_status->Type, 18,
        CPER_GENERIC_ERROR_TYPES_KEYS,
        CPER_GENERIC_ERROR_TYPES_VALUES,
        CPER_GENERIC_ERROR_TYPES_DESCRIPTIONS,
        "Unknown (Reserved)"));

    //Boolean bit fields.
    json_object_object_add(error_status_ir, "addressSignal", json_object_new_boolean(error_status->AddressSignal));
    json_object_object_add(error_status_ir, "controlSignal", json_object_new_boolean(error_status->ControlSignal));
    json_object_object_add(error_status_ir, "dataSignal", json_object_new_boolean(error_status->DataSignal));
    json_object_object_add(error_status_ir, "detectedByResponder", json_object_new_boolean(error_status->DetectedByResponder));
    json_object_object_add(error_status_ir, "detectedByRequester", json_object_new_boolean(error_status->DetectedByRequester));
    json_object_object_add(error_status_ir, "firstError", json_object_new_boolean(error_status->FirstError));
    json_object_object_add(error_status_ir, "overflowDroppedLogs", json_object_new_boolean(error_status->OverflowNotLogged));
    
    return error_status_ir;
}

//Converts the given CPER-JSON generic error status into a CPER structure.
void ir_generic_error_status_to_cper(json_object* error_status, EFI_GENERIC_ERROR_STATUS* error_status_cper)
{
    error_status_cper->Type = readable_pair_to_integer(json_object_object_get(error_status, "errorType"));
    error_status_cper->AddressSignal = json_object_get_boolean(json_object_object_get(error_status, "addressSignal"));
    error_status_cper->ControlSignal = json_object_get_boolean(json_object_object_get(error_status, "controlSignal"));
    error_status_cper->DataSignal = json_object_get_boolean(json_object_object_get(error_status, "dataSignal"));
    error_status_cper->DetectedByResponder = json_object_get_boolean(json_object_object_get(error_status, "detectedByResponder"));
    error_status_cper->DetectedByRequester = json_object_get_boolean(json_object_object_get(error_status, "detectedByRequester"));
    error_status_cper->FirstError = json_object_get_boolean(json_object_object_get(error_status, "firstError"));
    error_status_cper->OverflowNotLogged = json_object_get_boolean(json_object_object_get(error_status, "overflowDroppedLogs"));
}

//Converts a single uniform struct of UINT64s into intermediate JSON IR format, given names for each field in byte order.
json_object* uniform_struct64_to_ir(UINT64* start, int len, const char* names[])
{
    json_object* result = json_object_new_object();

    UINT64* cur = start;
    for (int i=0; i<len; i++)
    {
        json_object_object_add(result, names[i], json_object_new_uint64(*cur));
        cur++;
    }

    return result;
}

//Converts a single uniform struct of UINT32s into intermediate JSON IR format, given names for each field in byte order.
json_object* uniform_struct_to_ir(UINT32* start, int len, const char* names[])
{
    json_object* result = json_object_new_object();

    UINT32* cur = start;
    for (int i=0; i<len; i++)
    {
        json_object_object_add(result, names[i], json_object_new_uint64(*cur));
        cur++;
    }

    return result;
}

//Converts a single object containing UINT32s into a uniform struct.
void ir_to_uniform_struct64(json_object* ir, UINT64* start, int len, const char* names[])
{
    UINT64* cur = start;
    for (int i=0; i<len; i++)
    {
        *cur = json_object_get_uint64(json_object_object_get(ir, names[i]));
        cur++;
    }
}

//Converts a single object containing UINT32s into a uniform struct.
void ir_to_uniform_struct(json_object* ir, UINT32* start, int len, const char* names[])
{
    UINT32* cur = start;
    for (int i=0; i<len; i++)
    {
        *cur = (UINT32)json_object_get_uint64(json_object_object_get(ir, names[i]));
        cur++;
    }
}

//Converts a single integer value to an object containing a value, and a readable name if possible.
json_object* integer_to_readable_pair(UINT64 value, int len, int keys[], const char* values[], const char* default_value)
{
    json_object* result = json_object_new_object();
    json_object_object_add(result, "value", json_object_new_uint64(value));

    //Search for human readable name, add.
    const char* name = default_value;
    for (int i=0; i<len; i++)
    {
        if (keys[i] == value)
            name = values[i];
    }

    json_object_object_add(result, "name", json_object_new_string(name));
    return result;
}

//Converts a single integer value to an object containing a value, readable name and description if possible.
json_object* integer_to_readable_pair_with_desc(int value, int len, int keys[], const char* values[], 
    const char* descriptions[], const char* default_value) 
{
    json_object* result = json_object_new_object();
    json_object_object_add(result, "value", json_object_new_int(value));

    //Search for human readable name, add.
    const char* name = default_value;
    for (int i=0; i<len; i++)
    {
        if (keys[i] == value) 
        {
            name = values[i];
            json_object_object_add(result, "description", json_object_new_string(descriptions[i]));
        }
    }

    json_object_object_add(result, "name", json_object_new_string(name));
    return result;
}

//Returns a single UINT64 value from the given readable pair object.
//Assumes the integer value is held in the "value" field.
UINT64 readable_pair_to_integer(json_object* pair)
{
    return json_object_get_uint64(json_object_object_get(pair, "value"));
}

//Converts the given 64 bit bitfield to IR, assuming bit 0 starts on the left.
json_object* bitfield_to_ir(UINT64 bitfield, int num_fields, const char* names[])
{
    json_object* result = json_object_new_object();
    for (int i=0; i<num_fields; i++)
    {
        json_object_object_add(result, names[i], json_object_new_boolean((bitfield >> i) & 0b1));
    }

    return result;
}

//Converts the given IR bitfield into a standard UINT64 bitfield, with fields beginning from bit 0.
UINT64 ir_to_bitfield(json_object* ir, int num_fields, const char* names[])
{
    UINT64 result = 0x0;
    for (int i=0; i<num_fields; i++)
    {
        if (json_object_get_boolean(json_object_object_get(ir, names[i])))
            result |= (0x1 << i);
    }

    return result;
}

//Converts the given UINT64 array into a JSON IR array, given the length.
json_object* uint64_array_to_ir_array(UINT64* array, int len)
{
    json_object* array_ir = json_object_new_array();
    for (int i=0; i<len; i++)
        json_object_array_add(array_ir, json_object_new_uint64(array[i]));
    return array_ir;
}

//Converts a single UINT16 revision number into JSON IR representation.
json_object* revision_to_ir(UINT16 revision)
{
    json_object* revision_info = json_object_new_object();
    json_object_object_add(revision_info, "major", json_object_new_int(revision >> 8));
    json_object_object_add(revision_info, "minor", json_object_new_int(revision & 0xFF));
    return revision_info;
}

//Returns the appropriate string for the given integer severity.
const char* severity_to_string(UINT8 severity)
{
    return severity < 4 ? CPER_SEVERITY_TYPES[severity] : "Unknown";
}

//Converts a single EFI timestamp to string, at the given output.
//Output must be at least TIMESTAMP_LENGTH bytes long.
void timestamp_to_string(char* out, EFI_ERROR_TIME_STAMP* timestamp)
{
    sprintf(out, "%02d%02d-%02d-%02dT%02d:%02d:%02d.000", 
            timestamp->Century,
            timestamp->Year,
            timestamp->Month,
            timestamp->Day,
            timestamp->Hours,
            timestamp->Minutes,
            timestamp->Seconds);
}

//Converts a single timestamp string to an EFI timestamp.
void string_to_timestamp(EFI_ERROR_TIME_STAMP* out, const char* timestamp)
{
    //Ignore invalid timestamps.
    if (timestamp == NULL)
        return;

    sscanf(timestamp, "%02hhd%02hhd-%02hhd-%02hhdT%02hhd:%02hhd:%02hhd.000", 
            &out->Century,
            &out->Year,
            &out->Month,
            &out->Day,
            &out->Hours,
            &out->Minutes,
            &out->Seconds);
}

//Helper function to convert an EDK EFI GUID into a string for intermediate use.
void guid_to_string(char* out, EFI_GUID* guid)
{
    sprintf(out, "%08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x", 
        guid->Data1, 
        guid->Data2, 
        guid->Data3,
        guid->Data4[0],
        guid->Data4[1],
        guid->Data4[2],
        guid->Data4[3],
        guid->Data4[4],
        guid->Data4[5],
        guid->Data4[6],
        guid->Data4[7]);
}

//Helper function to convert a string into an EDK EFI GUID.
void string_to_guid(EFI_GUID* out, const char* guid)
{
    //Ignore invalid GUIDs.
    if (guid == NULL)
        return;

    sscanf(guid, "%08x-%04hx-%04hx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx", 
        &out->Data1, 
        &out->Data2, 
        &out->Data3,
        out->Data4,
        out->Data4 + 1,
        out->Data4 + 2,
        out->Data4 + 3,
        out->Data4 + 4,
        out->Data4 + 5,
        out->Data4 + 6,
        out->Data4 + 7);
}

//Returns one if two EFI GUIDs are equal, zero otherwise.
int guid_equal(EFI_GUID* a, EFI_GUID* b)
{
    //Check top base 3 components.
    if (a->Data1 != b->Data1
        || a->Data2 != b->Data2
        || a->Data3 != b->Data3) 
    {
        return 0;
    }

    //Check Data4 array for equality.
    for (int i=0; i<8; i++)
    {
        if (a->Data4[i] != b->Data4[i])
            return 0;
    }

    return 1;
}

//Converts the given BCD byte to a standard integer.
int bcd_to_int(UINT8 bcd)
{
    return ((bcd & 0xF0) >> 4) * 10 + (bcd & 0x0F);
}

//Converts the given integer to a single byte BCD.
UINT8 int_to_bcd(int value)
{
    UINT8 result = 0;
    int shift = 0;
    while (value > 0) {
        result |= (value % 10) << (shift++ << 2);
        value /= 10;
    }

    return result;
}