path: root/src/d_iwad.c

// Emacs style mode select   -*- C++ -*- 
//-----------------------------------------------------------------------------
//
// Copyright(C) 2006 Simon Howard
//
// 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.
//
// DESCRIPTION:
//     Search for and locate an IWAD file, and initialise according
//     to the IWAD type.
//
//-----------------------------------------------------------------------------

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>

#include "deh_str.h"
#include "doomkeys.h"
#include "d_iwad.h"
#include "i_system.h"
#include "m_argv.h"
#include "m_config.h"
#include "m_misc.h"
#include "w_wad.h"
#include "z_zone.h"

// Array of locations to search for IWAD files
//
// "128 IWAD search directories should be enough for anybody".

#define MAX_IWAD_DIRS 128

static boolean iwad_dirs_built = false;
static char *iwad_dirs[MAX_IWAD_DIRS];
static int num_iwad_dirs = 0;

static void AddIWADDir(char *dir)
{
    if (num_iwad_dirs < MAX_IWAD_DIRS)
    {
        iwad_dirs[num_iwad_dirs] = dir;
        ++num_iwad_dirs;
    }
}

// This is Windows-specific code that automatically finds the location
// of installed IWAD files.  The registry is inspected to find special
// keys installed by the Windows installers for various CD versions
// of Doom.  From these keys we can deduce where to find an IWAD.

#ifdef _WIN32

#define WIN32_LEAN_AND_MEAN
#include <windows.h>

typedef struct 
{
    HKEY root;
    char *path;
    char *value;
} registry_value_t;

#define UNINSTALLER_STRING "\\uninstl.exe /S "

// Keys installed by the various CD editions.  These are actually the 
// commands to invoke the uninstaller and look like this:
//
// C:\Program Files\Path\uninstl.exe /S C:\Program Files\Path
//
// With some munging we can find where Doom was installed.

static registry_value_t uninstall_values[] = 
{
    // Ultimate Doom, CD version (Depths of Doom trilogy)

    {
        HKEY_LOCAL_MACHINE, 
        "Software\\Microsoft\\Windows\\CurrentVersion\\"
            "Uninstall\\Ultimate Doom for Windows 95",
        "UninstallString",
    },

    // Doom II, CD version (Depths of Doom trilogy)

    {
        HKEY_LOCAL_MACHINE, 
        "Software\\Microsoft\\Windows\\CurrentVersion\\"
            "Uninstall\\Doom II for Windows 95",
        "UninstallString",
    },

    // Final Doom

    {
        HKEY_LOCAL_MACHINE, 
        "Software\\Microsoft\\Windows\\CurrentVersion\\"
            "Uninstall\\Final Doom for Windows 95",
        "UninstallString",
    },

    // Shareware version

    {
        HKEY_LOCAL_MACHINE, 
        "Software\\Microsoft\\Windows\\CurrentVersion\\"
            "Uninstall\\Doom Shareware for Windows 95",
        "UninstallString",
    },
};

// Value installed by the Collector's Edition when it is installed

static registry_value_t collectors_edition_value =
{
    HKEY_LOCAL_MACHINE,
    "Software\\Activision\\DOOM Collector's Edition\\v1.0",
    "INSTALLPATH",
};

// Subdirectories of the above install path, where IWADs are installed.

static char *collectors_edition_subdirs[] = 
{
    "Doom2",
    "Final Doom",
    "Ultimate Doom",
};

// Location where Steam is installed

static registry_value_t steam_install_location =
{
    HKEY_LOCAL_MACHINE,
    "Software\\Valve\\Steam",
    "InstallPath",
};

// Subdirs of the steam install directory where IWADs are found

static char *steam_install_subdirs[] =
{
    "steamapps\\common\\doom 2\\base",
    "steamapps\\common\\final doom\\base",
    "steamapps\\common\\ultimate doom\\base",
    "steamapps\\common\\hexen\\base",
    "steamapps\\common\\heretic shadow of the serpent riders"
};

static char *GetRegistryString(registry_value_t *reg_val)
{
    HKEY key;
    DWORD len;
    DWORD valtype;
    char *result;

    // Open the key (directory where the value is stored)

    if (RegOpenKeyEx(reg_val->root, reg_val->path, 0, KEY_READ, &key) 
          != ERROR_SUCCESS)
    {
        return NULL;
    }

    // Find the type and length of the string

    if (RegQueryValueEx(key, reg_val->value, NULL, &valtype, NULL, &len) 
          != ERROR_SUCCESS)
    {
        return NULL;
    }

    // Only accept strings

    if (valtype != REG_SZ)
    {
        return NULL;
    }

    // Allocate a buffer for the value and read the value

    result = malloc(len);

    if (RegQueryValueEx(key, reg_val->value, NULL, &valtype, (unsigned char *) result, &len) 
          != ERROR_SUCCESS)
    {
        free(result);
        return NULL;
    }

    // Close the key
        
    RegCloseKey(key);

    return result;
}

// Check for the uninstall strings from the CD versions

static void CheckUninstallStrings(void)
{
    unsigned int i;

    for (i=0; i<arrlen(uninstall_values); ++i)
    {
        char *val;
        char *path;
        char *unstr;

        val = GetRegistryString(&uninstall_values[i]);

        if (val == NULL)
        {
            continue;
        }

        unstr = strstr(val, UNINSTALLER_STRING);

        if (unstr == NULL)
        {
            free(val);
        }
        else
        {
            path = unstr + strlen(UNINSTALLER_STRING);

            AddIWADDir(path);
        }
    }
}

// Check for Doom: Collector's Edition

static void CheckCollectorsEdition(void)
{
    char *install_path;
    char *subpath;
    unsigned int i;

    install_path = GetRegistryString(&collectors_edition_value);

    if (install_path == NULL)
    {
        return;
    }

    for (i=0; i<arrlen(collectors_edition_subdirs); ++i)
    {
        subpath = malloc(strlen(install_path)
                         + strlen(collectors_edition_subdirs[i])
                         + 5);

        sprintf(subpath, "%s\\%s", install_path, collectors_edition_subdirs[i]);

        AddIWADDir(subpath);
    }

    free(install_path);
}


// Check for Doom downloaded via Steam

static void CheckSteamEdition(void)
{
    char *install_path;
    char *subpath;
    size_t i;

    install_path = GetRegistryString(&steam_install_location);

    if (install_path == NULL)
    {
        return;
    }

    for (i=0; i<arrlen(steam_install_subdirs); ++i)
    {
        subpath = malloc(strlen(install_path) 
                         + strlen(steam_install_subdirs[i]) + 5);

        sprintf(subpath, "%s\\%s", install_path, steam_install_subdirs[i]);

        AddIWADDir(subpath);
    }
}

// Default install directories for DOS Doom

static void CheckDOSDefaults(void)
{
    // These are the default install directories used by the deice
    // installer program:

    AddIWADDir("\\doom2");              // Doom II
    AddIWADDir("\\plutonia");           // Final Doom
    AddIWADDir("\\tnt");
    AddIWADDir("\\doom_se");            // Ultimate Doom
    AddIWADDir("\\doom");               // Shareware / Registered Doom
    AddIWADDir("\\dooms");              // Shareware versions
    AddIWADDir("\\doomsw");
}

#endif

// Search a directory to try to find an IWAD
// Returns the location of the IWAD if found, otherwise NULL.

static char *SearchDirectoryForIWAD(char *dir, iwad_t *iwads,
                                    GameMission_t *mission)
{
    size_t i;

    for (i=0; iwads[i].name != NULL; ++i) 
    {
        char *filename; 
        char *iwadname;

        iwadname = DEH_String(iwads[i].name);
        
        filename = malloc(strlen(dir) + strlen(iwadname) + 3);

        if (!strcmp(dir, "."))
        {
            strcpy(filename, iwadname);
        }
        else
        {
            sprintf(filename, "%s%c%s", dir, DIR_SEPARATOR, iwadname);
        }

        if (M_FileExists(filename))
        {
            *mission = iwads[i].mission;

            return filename;
        }

        free(filename);
    }

    return NULL;
}

// When given an IWAD with the '-iwad' parameter,
// attempt to identify it by its name.

static GameMission_t IdentifyIWADByName(char *name, iwad_t *iwads)
{
    size_t i;
    GameMission_t mission;

    mission = none;
    
    for (i=0; iwads[i].name != NULL; ++i)
    {
        char *iwadname;

        iwadname = DEH_String(iwads[i].name);

        if (strlen(name) < strlen(iwadname))
            continue;

        // Check if it ends in this IWAD name.

        if (!strcasecmp(name + strlen(name) - strlen(iwadname), 
                        iwadname))
        {
            mission = iwads[i].mission;
            break;
        }
    }

    return mission;
}

//
// Add directories from the list in the DOOMWADPATH environment variable.
// 

static void AddDoomWadPath(void)
{
    char *doomwadpath;
    char *p;

    // Check the DOOMWADPATH environment variable.

    doomwadpath = getenv("DOOMWADPATH");

    if (doomwadpath == NULL)
    {
        return;
    }

    doomwadpath = strdup(doomwadpath);

    // Add the initial directory

    AddIWADDir(doomwadpath);

    // Split into individual dirs within the list.

    p = doomwadpath;

    for (;;)
    {
        p = strchr(p, PATH_SEPARATOR);

        if (p != NULL)
        {
            // Break at the separator and store the right hand side
            // as another iwad dir
  
            *p = '\0';
            p += 1;

            AddIWADDir(p);
        }
        else
        {
            break;
        }
    }
}


//
// Build a list of IWAD files
//

static void BuildIWADDirList(void)
{
    char *doomwaddir;

    if (iwad_dirs_built)
    {
        return;
    }

    // Look in the current directory.  Doom always does this.

    AddIWADDir(".");

    // Add DOOMWADDIR if it is in the environment

    doomwaddir = getenv("DOOMWADDIR");

    if (doomwaddir != NULL)
    {
        AddIWADDir(doomwaddir);
    }        

    // Add dirs from DOOMWADPATH

    AddDoomWadPath();

#ifdef _WIN32

    // Search the registry and find where IWADs have been installed.

    CheckUninstallStrings();
    CheckCollectorsEdition();
    CheckSteamEdition();
    CheckDOSDefaults();

#else

    // Standard places where IWAD files are installed under Unix.

    AddIWADDir("/usr/share/games/doom");
    AddIWADDir("/usr/local/share/games/doom");

#endif

    // Don't run this function again.

    iwad_dirs_built = true;
}

//
// Searches WAD search paths for an WAD with a specific filename.
// 

char *D_FindWADByName(char *name)
{
    char *buf;
    int i;
    boolean exists;
    
    // Absolute path?

    if (M_FileExists(name))
    {
        return name;
    }

    BuildIWADDirList();
    
    // Search through all IWAD paths for a file with the given name.

    for (i=0; i<num_iwad_dirs; ++i)
    {
        // Construct a string for the full path

        buf = malloc(strlen(iwad_dirs[i]) + strlen(name) + 5);
        sprintf(buf, "%s%c%s", iwad_dirs[i], DIR_SEPARATOR, name);

        exists = M_FileExists(buf);

        if (exists)
        {
            return buf;
        }

        free(buf);
    }

    // File not found

    return NULL;
}

//
// D_TryWADByName
//
// Searches for a WAD by its filename, or passes through the filename
// if not found.
//

char *D_TryFindWADByName(char *filename)
{
    char *result;

    result = D_FindWADByName(filename);

    if (result != NULL)
    {
        return result;
    }
    else
    {
        return filename;
    }
}

//
// FindIWAD
// Checks availability of IWAD files by name,
// to determine whether registered/commercial features
// should be executed (notably loading PWADs).
//

char *D_FindIWAD(iwad_t *iwads, GameMission_t *mission)
{
    char *result;
    char *iwadfile;
    int iwadparm;
    int i;

    // Check for the -iwad parameter

    //!
    // Specify an IWAD file to use.
    //
    // @arg <file>
    //

    iwadparm = M_CheckParm("-iwad");

    if (iwadparm)
    {
        // Search through IWAD dirs for an IWAD with the given name.

        iwadfile = myargv[iwadparm + 1];

        result = D_FindWADByName(iwadfile);

        if (result == NULL)
        {
            I_Error("IWAD file '%s' not found!", iwadfile);
        }
        
        *mission = IdentifyIWADByName(result, iwads);
    }
    else
    {
        // Search through the list and look for an IWAD

        result = NULL;

        BuildIWADDirList();
    
        for (i=0; result == NULL && i<num_iwad_dirs; ++i)
        {
            result = SearchDirectoryForIWAD(iwad_dirs[i], iwads, mission);
        }
    }

    return result;
}

// Clever hack: Setup can invoke Doom to determine which IWADs are installed.
// Doom searches install paths and exits with the return code being a 
// bitmask of the installed IWAD files.

void D_FindInstalledIWADs(iwad_t *iwads)
{
    unsigned int i;
    int result;

    BuildIWADDirList();

    result = 0;

    for (i=0; i<arrlen(iwads); ++i)
    {
        if (D_FindWADByName(iwads[i].name) != NULL)
        {
            result |= 1 << i;
        }
    }

    exit(result);
}