Thread: String is getting mysteriously knackered

Hi, I am trying to write a program to open zzt files, but I have come across a problem which I don't understand.

If I printf the world.title string before I have called load_board it works fine, but if I try and printf it after load_board has been called it crashes. This makes me think that the load_board function is crapping over the world.title string, but I can't see where its touching it at all!

Code:

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>

/*    unsigned short int c;   / Two byte thingy */
/*    unsigned char d;        / One byte thingy */


/* Map structure */
struct Sworld
{
    int board_count;
    int start_board;
    
    int start_ammo;
    int start_gems;
    int start_health;
    int start_torches;
    
    int torch_cycles_left;
    int energiser_cycles_left;
    
    bool blue_key;
    bool green_key;
    bool cyan_key;
    bool red_key;
    bool purple_key;
    bool yellow_key;
    bool white_key;
    
    int start_score;
    
    char *title;
    int time_left;
    
    bool saved_game;
}; 

/* Tile structure */
struct Stile
{
    char code;
    char colour;
};
    
/* Board Structure */
struct Sboard
{
    char *title;
    char *message;
    struct Stile tile[1500];
    
    int object_count;
    int maximum_shots_fired;
    int time_limit;
    
    
    int board_north;
    int board_south;
    int board_west;
    int board_east;
    
    bool dark;
    bool teleport_when_hurt;    
};    

/* Functions */
bool load_world(char *file_name);
void load_board(FILE *file_pointer);

/* Variables */
struct Sworld world;
struct Sboard board;

int main(int argc, char *argv[])
{
  
    if (load_world("BOB.ZZT") == false)
        printf("Cock up loading map\n");
       
   /* if (load_world("SAVED.SAV") == false)
        printf("Cock up loading map\n"); */
  
    printf("map title: %s\n", world.title);  

    if (world.saved_game == true)
        printf("Its a saved game\n");
    else
        printf("Its not a saved game\n");

    system("PAUSE");	
    
    free(world.title);
    return 0;
}

bool load_world(char *file_name)
{
    FILE *file_pointer;
    char buffer[512];       /* Header goes here */
    int i, title_length;
    
    file_pointer = fopen(file_name, "r");
    if (file_pointer == NULL)
    {
        printf("FAILED opening world file: %s\n", file_name);
        system("PAUSE");
        return false;
    }
    else
        printf("Opened world file: %s\n", file_name);    
    
    for (i = 0; i < 512; i++)
        buffer[i] = getc(file_pointer);
    
    world.board_count = (unsigned short)buffer[2] + buffer[3] * 256;
    world.start_ammo = (unsigned short)buffer[4] + buffer[5] * 256;
    world.start_gems = (unsigned short)buffer[6] + buffer[7] * 256;
    world.blue_key = buffer[8];
    world.green_key = buffer[9];
    world.cyan_key = buffer[10];
    world.red_key = buffer[11];
    world.purple_key = buffer[12];
    world.yellow_key = buffer[13];
    world.white_key = buffer[14];
    world.start_health = (unsigned short)buffer[15] + buffer[16] * 256;
    world.start_board = (unsigned short)buffer[17] + buffer[18] * 256;
    world.start_torches = (unsigned short)buffer[19] + buffer[20] * 256;
    world.torch_cycles_left = (unsigned short)buffer[21] + buffer[22] * 256;
    world.energiser_cycles_left = (unsigned short)buffer[23] + buffer[24] * 256;
    world.start_score = (unsigned short)buffer[27] + buffer[28] * 256;
    
    title_length = buffer[29];
    world.title = malloc(title_length + 1);
    for (i = 0; i < title_length; i++)
        world.title[i] = buffer[30 + i];
    world.title[i] = '\0'; 
    
    world.saved_game = buffer[264];
    
    printf("Board Count: %d\n",world.board_count);
    
    printf("Loaded world: %s\n", world.title);
    
    load_board(file_pointer);

    fclose(file_pointer);

    return true;
}    

void load_board(FILE *file_pointer)
{
    char *buffer;
    int i, board_size, title_length;
    int current_tile = 0;
    
    /* Read the board into the buffer */
    buffer = malloc(53);
    
    for (i = 0; i < 53; i++)
        buffer[i] = getc(file_pointer);
    
    /* Get the board size */    
    board_size = (unsigned short)buffer[0] + buffer[1] * 256; 
        
    /* Get the title */
    title_length = buffer[2];
    board.title = malloc(title_length + 1);
    for (i = 0; i < title_length; i++)
        board.title[i] = buffer[3 + i];
    board.title[i] = '\0';
    
    free(buffer);
    
    printf("Board title: %s\n", board.title);
    
    buffer = malloc(3);
    
    /* Get all the tiles put into the board.tile array */
    while (current_tile < 1500)
    {    
        for (i = 0; i < 3; i++)
            buffer[i] = getc(file_pointer);
        
        printf("Repeat amount: %d\n",buffer[0]);
        printf("Code: %d\n",buffer[1]);
        printf("Colour: %d\n",buffer[2]);
        
        
        
        for (i = 0; i < buffer[0]; i++)
        {
            board.tile[current_tile + i].code = buffer[1];
            board.tile[current_tile + i].colour = buffer[2];
            
            current_tile++;
        }   
        printf("Current_tile: %d\n",current_tile);
        system("PAUSE");
        
    }     

    free(board.title);
    free(buffer);
}