ldata.c

/**

    File:       ldata.c

    Project:    DCPU-16 Tools
    Component:  LibDCPU-ci-objfmt

    Authors:    James Rhodes

    Description:    Defines functions used to retrieve the
            linker table from an object file.

**/

#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "ldata.h"

struct ldata_entry* ldata_read(FILE* in)
{
    struct ldata_entry* result = malloc(sizeof(struct ldata_entry));

    // Read the character information (256 bytes).
    fread(result->label, 1, 256, in);
    fread(&result->mode, sizeof(uint8_t), 1, in);
    fread(&result->address, sizeof(uint16_t), 1, in);
    result->label[255] = '\0'; // Safety.

    return result;
}

void ldata_write(FILE* out, struct ldata_entry* entry)
{
    // The label part of the structure might not be
    // 256 bytes in memory, so we need to copy it first.
    char* cpy = malloc(256);
    memset(cpy, 0, 256);

    if (entry->label != NULL)
    {
        if (strlen(entry->label) + 1 < 256)
            memcpy(cpy, entry->label, strlen(entry->label) + 1);
        else
            memcpy(cpy, entry->label, 256);
    }

    cpy[255] = '\0'; // Safety.

    // Read the character information (256 bytes).
    fwrite(cpy, 1, 256, out);
    fwrite(&entry->mode, sizeof(uint8_t), 1, out);
    fwrite(&entry->address, sizeof(uint16_t), 1, out);
    free(cpy);
}

void ldata_free(struct ldata_entry* entry)
{
    free(entry);
}