misc/libphysfs/physfs.c
author nemo
Tue, 21 Aug 2018 15:11:28 -0400
branch0.9.24
changeset 13682 f60b3998ba56
parent 12453 89423b1db329
permissions -rw-r--r--
only-stats should never create visual gears. and lua should never rely on visual gears being created. critical is just to help ensure ones important to gameplay don't get lost in fast-forward

/**
 * PhysicsFS; a portable, flexible file i/o abstraction.
 *
 * Documentation is in physfs.h. It's verbose, honest.  :)
 *
 * Please see the file LICENSE.txt in the source's root directory.
 *
 *  This file written by Ryan C. Gordon.
 */

/* !!! FIXME: ERR_PAST_EOF shouldn't trigger for reads. Just return zero. */
/* !!! FIXME: use snprintf(), not sprintf(). */

#define __PHYSICSFS_INTERNAL__
#include "physfs_internal.h"


typedef struct __PHYSFS_DIRHANDLE__
{
    void *opaque;  /* Instance data unique to the archiver. */
    char *dirName;  /* Path to archive in platform-dependent notation. */
    char *mountPoint; /* Mountpoint in virtual file tree. */
    const PHYSFS_Archiver *funcs;  /* Ptr to archiver info for this handle. */
    struct __PHYSFS_DIRHANDLE__ *next;  /* linked list stuff. */
} DirHandle;


typedef struct __PHYSFS_FILEHANDLE__
{
    PHYSFS_Io *io;  /* Instance data unique to the archiver for this file. */
    PHYSFS_uint8 forReading; /* Non-zero if reading, zero if write/append */
    const DirHandle *dirHandle;  /* Archiver instance that created this */
    PHYSFS_uint8 *buffer;  /* Buffer, if set (NULL otherwise). Don't touch! */
    PHYSFS_uint32 bufsize;  /* Bufsize, if set (0 otherwise). Don't touch! */
    PHYSFS_uint32 buffill;  /* Buffer fill size. Don't touch! */
    PHYSFS_uint32 bufpos;  /* Buffer position. Don't touch! */
    struct __PHYSFS_FILEHANDLE__ *next;  /* linked list stuff. */
} FileHandle;


typedef struct __PHYSFS_ERRSTATETYPE__
{
    void *tid;
    PHYSFS_ErrorCode code;
    struct __PHYSFS_ERRSTATETYPE__ *next;
} ErrState;


/* General PhysicsFS state ... */
static int initialized = 0;
static ErrState *errorStates = NULL;
static DirHandle *searchPath = NULL;
static DirHandle *writeDir = NULL;
static FileHandle *openWriteList = NULL;
static FileHandle *openReadList = NULL;
static char *baseDir = NULL;
static char *userDir = NULL;
static char *prefDir = NULL;
static int allowSymLinks = 0;
static const PHYSFS_Archiver **archivers = NULL;
static const PHYSFS_ArchiveInfo **archiveInfo = NULL;
static volatile size_t numArchivers = 0;

/* mutexes ... */
static void *errorLock = NULL;     /* protects error message list.        */
static void *stateLock = NULL;     /* protects other PhysFS static state. */

/* allocator ... */
static int externalAllocator = 0;
PHYSFS_Allocator allocator;


/* PHYSFS_Io implementation for i/o to physical filesystem... */

/* !!! FIXME: maybe refcount the paths in a string pool? */
typedef struct __PHYSFS_NativeIoInfo
{
    void *handle;
    const char *path;
    int mode;   /* 'r', 'w', or 'a' */
} NativeIoInfo;

static PHYSFS_sint64 nativeIo_read(PHYSFS_Io *io, void *buf, PHYSFS_uint64 len)
{
    NativeIoInfo *info = (NativeIoInfo *) io->opaque;
    return __PHYSFS_platformRead(info->handle, buf, len);
} /* nativeIo_read */

static PHYSFS_sint64 nativeIo_write(PHYSFS_Io *io, const void *buffer,
                                    PHYSFS_uint64 len)
{
    NativeIoInfo *info = (NativeIoInfo *) io->opaque;
    return __PHYSFS_platformWrite(info->handle, buffer, len);
} /* nativeIo_write */

static int nativeIo_seek(PHYSFS_Io *io, PHYSFS_uint64 offset)
{
    NativeIoInfo *info = (NativeIoInfo *) io->opaque;
    return __PHYSFS_platformSeek(info->handle, offset);
} /* nativeIo_seek */

static PHYSFS_sint64 nativeIo_tell(PHYSFS_Io *io)
{
    NativeIoInfo *info = (NativeIoInfo *) io->opaque;
    return __PHYSFS_platformTell(info->handle);
} /* nativeIo_tell */

static PHYSFS_sint64 nativeIo_length(PHYSFS_Io *io)
{
    NativeIoInfo *info = (NativeIoInfo *) io->opaque;
    return __PHYSFS_platformFileLength(info->handle);
} /* nativeIo_length */

static PHYSFS_Io *nativeIo_duplicate(PHYSFS_Io *io)
{
    NativeIoInfo *info = (NativeIoInfo *) io->opaque;
    return __PHYSFS_createNativeIo(info->path, info->mode);
} /* nativeIo_duplicate */

static int nativeIo_flush(PHYSFS_Io *io)
{
    return __PHYSFS_platformFlush(io->opaque);
} /* nativeIo_flush */

static void nativeIo_destroy(PHYSFS_Io *io)
{
    NativeIoInfo *info = (NativeIoInfo *) io->opaque;
    __PHYSFS_platformClose(info->handle);
    allocator.Free((void *) info->path);
    allocator.Free(info);
    allocator.Free(io);
} /* nativeIo_destroy */

static const PHYSFS_Io __PHYSFS_nativeIoInterface =
{
    CURRENT_PHYSFS_IO_API_VERSION, NULL,
    nativeIo_read,
    nativeIo_write,
    nativeIo_seek,
    nativeIo_tell,
    nativeIo_length,
    nativeIo_duplicate,
    nativeIo_flush,
    nativeIo_destroy
};

PHYSFS_Io *__PHYSFS_createNativeIo(const char *path, const int mode)
{
    PHYSFS_Io *io = NULL;
    NativeIoInfo *info = NULL;
    void *handle = NULL;
    char *pathdup = NULL;

    assert((mode == 'r') || (mode == 'w') || (mode == 'a'));

    io = (PHYSFS_Io *) allocator.Malloc(sizeof (PHYSFS_Io));
    GOTO_IF_MACRO(!io, PHYSFS_ERR_OUT_OF_MEMORY, createNativeIo_failed);
    info = (NativeIoInfo *) allocator.Malloc(sizeof (NativeIoInfo));
    GOTO_IF_MACRO(!info, PHYSFS_ERR_OUT_OF_MEMORY, createNativeIo_failed);
    pathdup = (char *) allocator.Malloc(strlen(path) + 1);
    GOTO_IF_MACRO(!pathdup, PHYSFS_ERR_OUT_OF_MEMORY, createNativeIo_failed);

    if (mode == 'r')
        handle = __PHYSFS_platformOpenRead(path);
    else if (mode == 'w')
        handle = __PHYSFS_platformOpenWrite(path);
    else if (mode == 'a')
        handle = __PHYSFS_platformOpenAppend(path);

    GOTO_IF_MACRO(!handle, ERRPASS, createNativeIo_failed);

    strcpy(pathdup, path);
    info->handle = handle;
    info->path = pathdup;
    info->mode = mode;
    memcpy(io, &__PHYSFS_nativeIoInterface, sizeof (*io));
    io->opaque = info;
    return io;

createNativeIo_failed:
    if (handle != NULL) __PHYSFS_platformClose(handle);
    if (pathdup != NULL) allocator.Free(pathdup);
    if (info != NULL) allocator.Free(info);
    if (io != NULL) allocator.Free(io);
    return NULL;
} /* __PHYSFS_createNativeIo */


/* PHYSFS_Io implementation for i/o to a memory buffer... */

typedef struct __PHYSFS_MemoryIoInfo
{
    const PHYSFS_uint8 *buf;
    PHYSFS_uint64 len;
    PHYSFS_uint64 pos;
    PHYSFS_Io *parent;
    volatile PHYSFS_uint32 refcount;
    void (*destruct)(void *);
} MemoryIoInfo;

static PHYSFS_sint64 memoryIo_read(PHYSFS_Io *io, void *buf, PHYSFS_uint64 len)
{
    MemoryIoInfo *info = (MemoryIoInfo *) io->opaque;
    const PHYSFS_uint64 avail = info->len - info->pos;
    assert(avail <= info->len);

    if (avail == 0)
        return 0;  /* we're at EOF; nothing to do. */

    if (len > avail)
        len = avail;

    memcpy(buf, info->buf + info->pos, (size_t) len);
    info->pos += len;
    return len;
} /* memoryIo_read */

static PHYSFS_sint64 memoryIo_write(PHYSFS_Io *io, const void *buffer,
                                    PHYSFS_uint64 len)
{
    BAIL_MACRO(PHYSFS_ERR_OPEN_FOR_READING, -1);
} /* memoryIo_write */

static int memoryIo_seek(PHYSFS_Io *io, PHYSFS_uint64 offset)
{
    MemoryIoInfo *info = (MemoryIoInfo *) io->opaque;
    BAIL_IF_MACRO(offset > info->len, PHYSFS_ERR_PAST_EOF, 0);
    info->pos = offset;
    return 1;
} /* memoryIo_seek */

static PHYSFS_sint64 memoryIo_tell(PHYSFS_Io *io)
{
    const MemoryIoInfo *info = (MemoryIoInfo *) io->opaque;
    return (PHYSFS_sint64) info->pos;
} /* memoryIo_tell */

static PHYSFS_sint64 memoryIo_length(PHYSFS_Io *io)
{
    const MemoryIoInfo *info = (MemoryIoInfo *) io->opaque;
    return (PHYSFS_sint64) info->len;
} /* memoryIo_length */

static PHYSFS_Io *memoryIo_duplicate(PHYSFS_Io *io)
{
    MemoryIoInfo *info = (MemoryIoInfo *) io->opaque;
    MemoryIoInfo *newinfo = NULL;
    PHYSFS_Io *parent = info->parent;
    PHYSFS_Io *retval = NULL;

    /* avoid deep copies. */
    assert((!parent) || (!((MemoryIoInfo *) parent->opaque)->parent) );

    /* share the buffer between duplicates. */
    if (parent != NULL)  /* dup the parent, increment its refcount. */
        return parent->duplicate(parent);

    /* we're the parent. */

    retval = (PHYSFS_Io *) allocator.Malloc(sizeof (PHYSFS_Io));
    BAIL_IF_MACRO(!retval, PHYSFS_ERR_OUT_OF_MEMORY, NULL);
    newinfo = (MemoryIoInfo *) allocator.Malloc(sizeof (MemoryIoInfo));
    if (!newinfo)
    {
        allocator.Free(retval);
        BAIL_MACRO(PHYSFS_ERR_OUT_OF_MEMORY, NULL);
    } /* if */

    /* !!! FIXME: want lockless atomic increment. */
    __PHYSFS_platformGrabMutex(stateLock);
    info->refcount++;
    __PHYSFS_platformReleaseMutex(stateLock);

    memset(newinfo, '\0', sizeof (*info));
    newinfo->buf = info->buf;
    newinfo->len = info->len;
    newinfo->pos = 0;
    newinfo->parent = io;
    newinfo->refcount = 0;
    newinfo->destruct = NULL;

    memcpy(retval, io, sizeof (*retval));
    retval->opaque = newinfo;
    return retval;
} /* memoryIo_duplicate */

static int memoryIo_flush(PHYSFS_Io *io) { return 1;  /* it's read-only. */ }

static void memoryIo_destroy(PHYSFS_Io *io)
{
    MemoryIoInfo *info = (MemoryIoInfo *) io->opaque;
    PHYSFS_Io *parent = info->parent;
    int should_die = 0;

    if (parent != NULL)
    {
        assert(info->buf == ((MemoryIoInfo *) info->parent->opaque)->buf);
        assert(info->len == ((MemoryIoInfo *) info->parent->opaque)->len);
        assert(info->refcount == 0);
        assert(info->destruct == NULL);
        allocator.Free(info);
        allocator.Free(io);
        parent->destroy(parent);  /* decrements refcount. */
        return;
    } /* if */

    /* we _are_ the parent. */
    assert(info->refcount > 0);  /* even in a race, we hold a reference. */

    /* !!! FIXME: want lockless atomic decrement. */
    __PHYSFS_platformGrabMutex(stateLock);
    info->refcount--;
    should_die = (info->refcount == 0);
    __PHYSFS_platformReleaseMutex(stateLock);

    if (should_die)
    {
        void (*destruct)(void *) = info->destruct;
        void *buf = (void *) info->buf;
        io->opaque = NULL;  /* kill this here in case of race. */
        allocator.Free(info);
        allocator.Free(io);
        if (destruct != NULL)
            destruct(buf);
    } /* if */
} /* memoryIo_destroy */


static const PHYSFS_Io __PHYSFS_memoryIoInterface =
{
    CURRENT_PHYSFS_IO_API_VERSION, NULL,
    memoryIo_read,
    memoryIo_write,
    memoryIo_seek,
    memoryIo_tell,
    memoryIo_length,
    memoryIo_duplicate,
    memoryIo_flush,
    memoryIo_destroy
};

PHYSFS_Io *__PHYSFS_createMemoryIo(const void *buf, PHYSFS_uint64 len,
                                   void (*destruct)(void *))
{
    PHYSFS_Io *io = NULL;
    MemoryIoInfo *info = NULL;

    io = (PHYSFS_Io *) allocator.Malloc(sizeof (PHYSFS_Io));
    GOTO_IF_MACRO(!io, PHYSFS_ERR_OUT_OF_MEMORY, createMemoryIo_failed);
    info = (MemoryIoInfo *) allocator.Malloc(sizeof (MemoryIoInfo));
    GOTO_IF_MACRO(!info, PHYSFS_ERR_OUT_OF_MEMORY, createMemoryIo_failed);

    memset(info, '\0', sizeof (*info));
    info->buf = (const PHYSFS_uint8 *) buf;
    info->len = len;
    info->pos = 0;
    info->parent = NULL;
    info->refcount = 1;
    info->destruct = destruct;

    memcpy(io, &__PHYSFS_memoryIoInterface, sizeof (*io));
    io->opaque = info;
    return io;

createMemoryIo_failed:
    if (info != NULL) allocator.Free(info);
    if (io != NULL) allocator.Free(io);
    return NULL;
} /* __PHYSFS_createMemoryIo */


/* PHYSFS_Io implementation for i/o to a PHYSFS_File... */

static PHYSFS_sint64 handleIo_read(PHYSFS_Io *io, void *buf, PHYSFS_uint64 len)
{
    return PHYSFS_readBytes((PHYSFS_File *) io->opaque, buf, len);
} /* handleIo_read */

static PHYSFS_sint64 handleIo_write(PHYSFS_Io *io, const void *buffer,
                                    PHYSFS_uint64 len)
{
    return PHYSFS_writeBytes((PHYSFS_File *) io->opaque, buffer, len);
} /* handleIo_write */

static int handleIo_seek(PHYSFS_Io *io, PHYSFS_uint64 offset)
{
    return PHYSFS_seek((PHYSFS_File *) io->opaque, offset);
} /* handleIo_seek */

static PHYSFS_sint64 handleIo_tell(PHYSFS_Io *io)
{
    return PHYSFS_tell((PHYSFS_File *) io->opaque);
} /* handleIo_tell */

static PHYSFS_sint64 handleIo_length(PHYSFS_Io *io)
{
    return PHYSFS_fileLength((PHYSFS_File *) io->opaque);
} /* handleIo_length */

static PHYSFS_Io *handleIo_duplicate(PHYSFS_Io *io)
{
    /*
     * There's no duplicate at the PHYSFS_File level, so we break the
     *  abstraction. We're allowed to: we're physfs.c!
     */
    FileHandle *origfh = (FileHandle *) io->opaque;
    FileHandle *newfh = (FileHandle *) allocator.Malloc(sizeof (FileHandle));
    PHYSFS_Io *retval = NULL;

    GOTO_IF_MACRO(!newfh, PHYSFS_ERR_OUT_OF_MEMORY, handleIo_dupe_failed);
    memset(newfh, '\0', sizeof (*newfh));

    retval = (PHYSFS_Io *) allocator.Malloc(sizeof (PHYSFS_Io));
    GOTO_IF_MACRO(!retval, PHYSFS_ERR_OUT_OF_MEMORY, handleIo_dupe_failed);

#if 0  /* we don't buffer the duplicate, at least not at the moment. */
    if (origfh->buffer != NULL)
    {
        newfh->buffer = (PHYSFS_uint8 *) allocator.Malloc(origfh->bufsize);
        if (!newfh->buffer)
            GOTO_MACRO(PHYSFS_ERR_OUT_OF_MEMORY, handleIo_dupe_failed);
        newfh->bufsize = origfh->bufsize;
    } /* if */
#endif

    newfh->io = origfh->io->duplicate(origfh->io);
    GOTO_IF_MACRO(!newfh->io, ERRPASS, handleIo_dupe_failed);

    newfh->forReading = origfh->forReading;
    newfh->dirHandle = origfh->dirHandle;

    __PHYSFS_platformGrabMutex(stateLock);
    if (newfh->forReading)
    {
        newfh->next = openReadList;
        openReadList = newfh;
    } /* if */
    else
    {
        newfh->next = openWriteList;
        openWriteList = newfh;
    } /* else */
    __PHYSFS_platformReleaseMutex(stateLock);

    memcpy(retval, io, sizeof (PHYSFS_Io));
    retval->opaque = newfh;
    return retval;
    
handleIo_dupe_failed:
    if (newfh)
    {
        if (newfh->io != NULL) newfh->io->destroy(newfh->io);
        if (newfh->buffer != NULL) allocator.Free(newfh->buffer);
        allocator.Free(newfh);
    } /* if */

    return NULL;
} /* handleIo_duplicate */

static int handleIo_flush(PHYSFS_Io *io)
{
    return PHYSFS_flush((PHYSFS_File *) io->opaque);
} /* handleIo_flush */

static void handleIo_destroy(PHYSFS_Io *io)
{
    if (io->opaque != NULL)
        PHYSFS_close((PHYSFS_File *) io->opaque);
    allocator.Free(io);
} /* handleIo_destroy */

static const PHYSFS_Io __PHYSFS_handleIoInterface =
{
    CURRENT_PHYSFS_IO_API_VERSION, NULL,
    handleIo_read,
    handleIo_write,
    handleIo_seek,
    handleIo_tell,
    handleIo_length,
    handleIo_duplicate,
    handleIo_flush,
    handleIo_destroy
};

static PHYSFS_Io *__PHYSFS_createHandleIo(PHYSFS_File *f)
{
    PHYSFS_Io *io = (PHYSFS_Io *) allocator.Malloc(sizeof (PHYSFS_Io));
    BAIL_IF_MACRO(!io, PHYSFS_ERR_OUT_OF_MEMORY, NULL);
    memcpy(io, &__PHYSFS_handleIoInterface, sizeof (*io));
    io->opaque = f;
    return io;
} /* __PHYSFS_createHandleIo */


/* functions ... */

typedef struct
{
    char **list;
    PHYSFS_uint32 size;
    PHYSFS_ErrorCode errcode;
} EnumStringListCallbackData;

static void enumStringListCallback(void *data, const char *str)
{
    void *ptr;
    char *newstr;
    EnumStringListCallbackData *pecd = (EnumStringListCallbackData *) data;

    if (pecd->errcode)
        return;

    ptr = allocator.Realloc(pecd->list, (pecd->size + 2) * sizeof (char *));
    newstr = (char *) allocator.Malloc(strlen(str) + 1);
    if (ptr != NULL)
        pecd->list = (char **) ptr;

    if ((ptr == NULL) || (newstr == NULL))
    {
        pecd->errcode = PHYSFS_ERR_OUT_OF_MEMORY;
        pecd->list[pecd->size] = NULL;
        PHYSFS_freeList(pecd->list);
        return;
    } /* if */

    strcpy(newstr, str);
    pecd->list[pecd->size] = newstr;
    pecd->size++;
} /* enumStringListCallback */


static char **doEnumStringList(void (*func)(PHYSFS_StringCallback, void *))
{
    EnumStringListCallbackData ecd;
    memset(&ecd, '\0', sizeof (ecd));
    ecd.list = (char **) allocator.Malloc(sizeof (char *));
    BAIL_IF_MACRO(!ecd.list, PHYSFS_ERR_OUT_OF_MEMORY, NULL);
    func(enumStringListCallback, &ecd);

    if (ecd.errcode)
    {
        PHYSFS_setErrorCode(ecd.errcode);
        return NULL;
    } /* if */

    ecd.list[ecd.size] = NULL;
    return ecd.list;
} /* doEnumStringList */


static void __PHYSFS_bubble_sort(void *a, size_t lo, size_t hi,
                                 int (*cmpfn)(void *, size_t, size_t),
                                 void (*swapfn)(void *, size_t, size_t))
{
    size_t i;
    int sorted;

    do
    {
        sorted = 1;
        for (i = lo; i < hi; i++)
        {
            if (cmpfn(a, i, i + 1) > 0)
            {
                swapfn(a, i, i + 1);
                sorted = 0;
            } /* if */
        } /* for */
    } while (!sorted);
} /* __PHYSFS_bubble_sort */


static void __PHYSFS_quick_sort(void *a, size_t lo, size_t hi,
                         int (*cmpfn)(void *, size_t, size_t),
                         void (*swapfn)(void *, size_t, size_t))
{
    size_t i;
    size_t j;
    size_t v;

    if ((hi - lo) <= PHYSFS_QUICKSORT_THRESHOLD)
        __PHYSFS_bubble_sort(a, lo, hi, cmpfn, swapfn);
    else
    {
        i = (hi + lo) / 2;

        if (cmpfn(a, lo, i) > 0) swapfn(a, lo, i);
        if (cmpfn(a, lo, hi) > 0) swapfn(a, lo, hi);
        if (cmpfn(a, i, hi) > 0) swapfn(a, i, hi);

        j = hi - 1;
        swapfn(a, i, j);
        i = lo;
        v = j;
        while (1)
        {
            while(cmpfn(a, ++i, v) < 0) { /* do nothing */ }
            while(cmpfn(a, --j, v) > 0) { /* do nothing */ }
            if (j < i)
                break;
            swapfn(a, i, j);
        } /* while */
        if (i != (hi-1))
            swapfn(a, i, hi-1);
        __PHYSFS_quick_sort(a, lo, j, cmpfn, swapfn);
        __PHYSFS_quick_sort(a, i+1, hi, cmpfn, swapfn);
    } /* else */
} /* __PHYSFS_quick_sort */


void __PHYSFS_sort(void *entries, size_t max,
                   int (*cmpfn)(void *, size_t, size_t),
                   void (*swapfn)(void *, size_t, size_t))
{
    /*
     * Quicksort w/ Bubblesort fallback algorithm inspired by code from here:
     *   https://www.cs.ubc.ca/spider/harrison/Java/sorting-demo.html
     */
    if (max > 0)
        __PHYSFS_quick_sort(entries, 0, max - 1, cmpfn, swapfn);
} /* __PHYSFS_sort */


static ErrState *findErrorForCurrentThread(void)
{
    ErrState *i;
    void *tid;

    if (errorLock != NULL)
        __PHYSFS_platformGrabMutex(errorLock);

    if (errorStates != NULL)
    {
        tid = __PHYSFS_platformGetThreadID();

        for (i = errorStates; i != NULL; i = i->next)
        {
            if (i->tid == tid)
            {
                if (errorLock != NULL)
                    __PHYSFS_platformReleaseMutex(errorLock);
                return i;
            } /* if */
        } /* for */
    } /* if */

    if (errorLock != NULL)
        __PHYSFS_platformReleaseMutex(errorLock);

    return NULL;   /* no error available. */
} /* findErrorForCurrentThread */


/* this doesn't reset the error state. */
static inline PHYSFS_ErrorCode currentErrorCode(void)
{
    const ErrState *err = findErrorForCurrentThread();
    return err ? err->code : PHYSFS_ERR_OK;
} /* currentErrorCode */


PHYSFS_ErrorCode PHYSFS_getLastErrorCode(void)
{
    ErrState *err = findErrorForCurrentThread();
    const PHYSFS_ErrorCode retval = (err) ? err->code : PHYSFS_ERR_OK;
    if (err)
        err->code = PHYSFS_ERR_OK;
    return retval;
} /* PHYSFS_getLastErrorCode */


PHYSFS_DECL const char *PHYSFS_getErrorByCode(PHYSFS_ErrorCode code)
{
    switch (code)
    {
        case PHYSFS_ERR_OK: return "no error";
        case PHYSFS_ERR_OTHER_ERROR: return "unknown error";
        case PHYSFS_ERR_OUT_OF_MEMORY: return "out of memory";
        case PHYSFS_ERR_NOT_INITIALIZED: return "not initialized";
        case PHYSFS_ERR_IS_INITIALIZED: return "already initialized";
        case PHYSFS_ERR_ARGV0_IS_NULL: return "argv[0] is NULL";
        case PHYSFS_ERR_UNSUPPORTED: return "unsupported";
        case PHYSFS_ERR_PAST_EOF: return "past end of file";
        case PHYSFS_ERR_FILES_STILL_OPEN: return "files still open";
        case PHYSFS_ERR_INVALID_ARGUMENT: return "invalid argument";
        case PHYSFS_ERR_NOT_MOUNTED: return "not mounted";
        case PHYSFS_ERR_NOT_FOUND: return "not found";
        case PHYSFS_ERR_SYMLINK_FORBIDDEN: return "symlinks are forbidden";
        case PHYSFS_ERR_NO_WRITE_DIR: return "write directory is not set";
        case PHYSFS_ERR_OPEN_FOR_READING: return "file open for reading";
        case PHYSFS_ERR_OPEN_FOR_WRITING: return "file open for writing";
        case PHYSFS_ERR_NOT_A_FILE: return "not a file";
        case PHYSFS_ERR_READ_ONLY: return "read-only filesystem";
        case PHYSFS_ERR_CORRUPT: return "corrupted";
        case PHYSFS_ERR_SYMLINK_LOOP: return "infinite symbolic link loop";
        case PHYSFS_ERR_IO: return "i/o error";
        case PHYSFS_ERR_PERMISSION: return "permission denied";
        case PHYSFS_ERR_NO_SPACE: return "no space available for writing";
        case PHYSFS_ERR_BAD_FILENAME: return "filename is illegal or insecure";
        case PHYSFS_ERR_BUSY: return "tried to modify a file the OS needs";
        case PHYSFS_ERR_DIR_NOT_EMPTY: return "directory isn't empty";
        case PHYSFS_ERR_OS_ERROR: return "OS reported an error";
        case PHYSFS_ERR_DUPLICATE: return "duplicate resource";
        case PHYSFS_ERR_BAD_PASSWORD: return "bad password";
    } /* switch */

    return NULL;  /* don't know this error code. */
} /* PHYSFS_getErrorByCode */


void PHYSFS_setErrorCode(PHYSFS_ErrorCode errcode)
{
    ErrState *err;

    if (!errcode)
        return;

    err = findErrorForCurrentThread();
    if (err == NULL)
    {
        err = (ErrState *) allocator.Malloc(sizeof (ErrState));
        if (err == NULL)
            return;   /* uhh...? */

        memset(err, '\0', sizeof (ErrState));
        err->tid = __PHYSFS_platformGetThreadID();

        if (errorLock != NULL)
            __PHYSFS_platformGrabMutex(errorLock);

        err->next = errorStates;
        errorStates = err;

        if (errorLock != NULL)
            __PHYSFS_platformReleaseMutex(errorLock);
    } /* if */

    err->code = errcode;
} /* PHYSFS_setErrorCode */


const char *PHYSFS_getLastError(void)
{
    const PHYSFS_ErrorCode err = PHYSFS_getLastErrorCode();
    return (err) ? PHYSFS_getErrorByCode(err) : NULL;
} /* PHYSFS_getLastError */


/* MAKE SURE that errorLock is held before calling this! */
static void freeErrorStates(void)
{
    ErrState *i;
    ErrState *next;

    for (i = errorStates; i != NULL; i = next)
    {
        next = i->next;
        allocator.Free(i);
    } /* for */

    errorStates = NULL;
} /* freeErrorStates */


void PHYSFS_getLinkedVersion(PHYSFS_Version *ver)
{
    if (ver != NULL)
    {
        ver->major = PHYSFS_VER_MAJOR;
        ver->minor = PHYSFS_VER_MINOR;
        ver->patch = PHYSFS_VER_PATCH;
    } /* if */
} /* PHYSFS_getLinkedVersion */


static const char *find_filename_extension(const char *fname)
{
    const char *retval = NULL;
    if (fname != NULL)
    {
        const char *p = strchr(fname, '.');
        retval = p;

        while (p != NULL)
        {
            p = strchr(p + 1, '.');
            if (p != NULL)
                retval = p;
        } /* while */

        if (retval != NULL)
            retval++;  /* skip '.' */
    } /* if */

    return retval;
} /* find_filename_extension */


static DirHandle *tryOpenDir(PHYSFS_Io *io, const PHYSFS_Archiver *funcs,
                             const char *d, int forWriting)
{
    DirHandle *retval = NULL;
    void *opaque = NULL;

    if (io != NULL)
        BAIL_IF_MACRO(!io->seek(io, 0), ERRPASS, NULL);

    opaque = funcs->openArchive(io, d, forWriting);
    if (opaque != NULL)
    {
        retval = (DirHandle *) allocator.Malloc(sizeof (DirHandle));
        if (retval == NULL)
            funcs->closeArchive(opaque);
        else
        {
            memset(retval, '\0', sizeof (DirHandle));
            retval->mountPoint = NULL;
            retval->funcs = funcs;
            retval->opaque = opaque;
        } /* else */
    } /* if */

    return retval;
} /* tryOpenDir */


static DirHandle *openDirectory(PHYSFS_Io *io, const char *d, int forWriting)
{
    DirHandle *retval = NULL;
    const PHYSFS_Archiver **i;
    const char *ext;
    int created_io = 0;

    assert((io != NULL) || (d != NULL));

    if (io == NULL)
    {
        /* DIR gets first shot (unlike the rest, it doesn't deal with files). */
        extern const PHYSFS_Archiver __PHYSFS_Archiver_DIR;
        retval = tryOpenDir(io, &__PHYSFS_Archiver_DIR, d, forWriting);
        if (retval != NULL)
            return retval;

        io = __PHYSFS_createNativeIo(d, forWriting ? 'w' : 'r');
        BAIL_IF_MACRO(!io, ERRPASS, 0);
        created_io = 1;
    } /* if */

    ext = find_filename_extension(d);
    if (ext != NULL)
    {
        /* Look for archivers with matching file extensions first... */
        for (i = archivers; (*i != NULL) && (retval == NULL); i++)
        {
            if (__PHYSFS_utf8stricmp(ext, (*i)->info.extension) == 0)
                retval = tryOpenDir(io, *i, d, forWriting);
        } /* for */

        /* failing an exact file extension match, try all the others... */
        for (i = archivers; (*i != NULL) && (retval == NULL); i++)
        {
            if (__PHYSFS_utf8stricmp(ext, (*i)->info.extension) != 0)
                retval = tryOpenDir(io, *i, d, forWriting);
        } /* for */
    } /* if */

    else  /* no extension? Try them all. */
    {
        for (i = archivers; (*i != NULL) && (retval == NULL); i++)
            retval = tryOpenDir(io, *i, d, forWriting);
    } /* else */

    if ((!retval) && (created_io))
        io->destroy(io);

    BAIL_IF_MACRO(!retval, PHYSFS_ERR_UNSUPPORTED, NULL);
    return retval;
} /* openDirectory */


/*
 * Make a platform-independent path string sane. Doesn't actually check the
 *  file hierarchy, it just cleans up the string.
 *  (dst) must be a buffer at least as big as (src), as this is where the
 *  cleaned up string is deposited.
 * If there are illegal bits in the path (".." entries, etc) then we
 *  return zero and (dst) is undefined. Non-zero if the path was sanitized.
 */
static int sanitizePlatformIndependentPath(const char *src, char *dst)
{
    char *prev;
    char ch;

    while (*src == '/')  /* skip initial '/' chars... */
        src++;

    prev = dst;
    do
    {
        ch = *(src++);

        if ((ch == ':') || (ch == '\\'))  /* illegal chars in a physfs path. */
            BAIL_MACRO(PHYSFS_ERR_BAD_FILENAME, 0);

        if (ch == '/')   /* path separator. */
        {
            *dst = '\0';  /* "." and ".." are illegal pathnames. */
            if ((strcmp(prev, ".") == 0) || (strcmp(prev, "..") == 0))
                BAIL_MACRO(PHYSFS_ERR_BAD_FILENAME, 0);

            while (*src == '/')   /* chop out doubles... */
                src++;

            if (*src == '\0') /* ends with a pathsep? */
                break;  /* we're done, don't add final pathsep to dst. */

            prev = dst + 1;
        } /* if */

        *(dst++) = ch;
    } while (ch != '\0');

    return 1;
} /* sanitizePlatformIndependentPath */


/*
 * Figure out if (fname) is part of (h)'s mountpoint. (fname) must be an
 *  output from sanitizePlatformIndependentPath(), so that it is in a known
 *  state.
 *
 * This only finds legitimate segments of a mountpoint. If the mountpoint is
 *  "/a/b/c" and (fname) is "/a/b/c", "/", or "/a/b/c/d", then the results are
 *  all zero. "/a/b" will succeed, though.
 */
static int partOfMountPoint(DirHandle *h, char *fname)
{
    /* !!! FIXME: This code feels gross. */
    int rc;
    size_t len, mntpntlen;

    if (h->mountPoint == NULL)
        return 0;
    else if (*fname == '\0')
        return 1;

    len = strlen(fname);
    mntpntlen = strlen(h->mountPoint);
    if (len > mntpntlen)  /* can't be a subset of mountpoint. */
        return 0;

    /* if true, must be not a match or a complete match, but not a subset. */
    if ((len + 1) == mntpntlen)
        return 0;

    rc = strncmp(fname, h->mountPoint, len); /* !!! FIXME: case insensitive? */
    if (rc != 0)
        return 0;  /* not a match. */

    /* make sure /a/b matches /a/b/ and not /a/bc ... */
    return h->mountPoint[len] == '/';
} /* partOfMountPoint */


static DirHandle *createDirHandle(PHYSFS_Io *io, const char *newDir,
                                  const char *mountPoint, int forWriting)
{
    DirHandle *dirHandle = NULL;
    char *tmpmntpnt = NULL;

    if (mountPoint != NULL)
    {
        const size_t len = strlen(mountPoint) + 1;
        tmpmntpnt = (char *) __PHYSFS_smallAlloc(len);
        GOTO_IF_MACRO(!tmpmntpnt, PHYSFS_ERR_OUT_OF_MEMORY, badDirHandle);
        if (!sanitizePlatformIndependentPath(mountPoint, tmpmntpnt))
            goto badDirHandle;
        mountPoint = tmpmntpnt;  /* sanitized version. */
    } /* if */

    dirHandle = openDirectory(io, newDir, forWriting);
    GOTO_IF_MACRO(!dirHandle, ERRPASS, badDirHandle);

    if (newDir == NULL)
        dirHandle->dirName = NULL;
    else
    {
        dirHandle->dirName = (char *) allocator.Malloc(strlen(newDir) + 1);
        if (!dirHandle->dirName)
            GOTO_MACRO(PHYSFS_ERR_OUT_OF_MEMORY, badDirHandle);
        strcpy(dirHandle->dirName, newDir);
    } /* else */

    if ((mountPoint != NULL) && (*mountPoint != '\0'))
    {
        dirHandle->mountPoint = (char *)allocator.Malloc(strlen(mountPoint)+2);
        if (!dirHandle->mountPoint)
            GOTO_MACRO(PHYSFS_ERR_OUT_OF_MEMORY, badDirHandle);
        strcpy(dirHandle->mountPoint, mountPoint);
        strcat(dirHandle->mountPoint, "/");
    } /* if */

    __PHYSFS_smallFree(tmpmntpnt);
    return dirHandle;

badDirHandle:
    if (dirHandle != NULL)
    {
        dirHandle->funcs->closeArchive(dirHandle->opaque);
        allocator.Free(dirHandle->dirName);
        allocator.Free(dirHandle->mountPoint);
        allocator.Free(dirHandle);
    } /* if */

    __PHYSFS_smallFree(tmpmntpnt);
    return NULL;
} /* createDirHandle */


/* MAKE SURE you've got the stateLock held before calling this! */
static int freeDirHandle(DirHandle *dh, FileHandle *openList)
{
    FileHandle *i;

    if (dh == NULL)
        return 1;

    for (i = openList; i != NULL; i = i->next)
        BAIL_IF_MACRO(i->dirHandle == dh, PHYSFS_ERR_FILES_STILL_OPEN, 0);

    dh->funcs->closeArchive(dh->opaque);
    allocator.Free(dh->dirName);
    allocator.Free(dh->mountPoint);
    allocator.Free(dh);
    return 1;
} /* freeDirHandle */


static char *calculateBaseDir(const char *argv0)
{
    const char dirsep = __PHYSFS_platformDirSeparator;
    char *retval = NULL;
    char *ptr = NULL;

    /* Give the platform layer first shot at this. */
    retval = __PHYSFS_platformCalcBaseDir(argv0);
    if (retval != NULL)
        return retval;

    /* We need argv0 to go on. */
    BAIL_IF_MACRO(argv0 == NULL, PHYSFS_ERR_ARGV0_IS_NULL, NULL);

    ptr = strrchr(argv0, dirsep);
    if (ptr != NULL)
    {
        const size_t size = ((size_t) (ptr - argv0)) + 1;
        retval = (char *) allocator.Malloc(size + 1);
        BAIL_IF_MACRO(!retval, PHYSFS_ERR_OUT_OF_MEMORY, NULL);
        memcpy(retval, argv0, size);
        retval[size] = '\0';
        return retval;
    } /* if */

    /* argv0 wasn't helpful. */
    BAIL_MACRO(PHYSFS_ERR_INVALID_ARGUMENT, NULL);
} /* calculateBaseDir */


static int initializeMutexes(void)
{
    errorLock = __PHYSFS_platformCreateMutex();
    if (errorLock == NULL)
        goto initializeMutexes_failed;

    stateLock = __PHYSFS_platformCreateMutex();
    if (stateLock == NULL)
        goto initializeMutexes_failed;

    return 1;  /* success. */

initializeMutexes_failed:
    if (errorLock != NULL)
        __PHYSFS_platformDestroyMutex(errorLock);

    if (stateLock != NULL)
        __PHYSFS_platformDestroyMutex(stateLock);

    errorLock = stateLock = NULL;
    return 0;  /* failed. */
} /* initializeMutexes */


static int doRegisterArchiver(const PHYSFS_Archiver *_archiver);

static int initStaticArchivers(void)
{
    #define REGISTER_STATIC_ARCHIVER(arc) { \
        extern const PHYSFS_Archiver __PHYSFS_Archiver_##arc; \
        if (!doRegisterArchiver(&__PHYSFS_Archiver_##arc)) { \
            return 0; \
        } \
    }

    #if PHYSFS_SUPPORTS_ZIP
        REGISTER_STATIC_ARCHIVER(ZIP);
    #endif
    #if PHYSFS_SUPPORTS_7Z
        REGISTER_STATIC_ARCHIVER(LZMA);
    #endif
    #if PHYSFS_SUPPORTS_GRP
        REGISTER_STATIC_ARCHIVER(GRP);
    #endif
    #if PHYSFS_SUPPORTS_QPAK
        REGISTER_STATIC_ARCHIVER(QPAK);
    #endif
    #if PHYSFS_SUPPORTS_HOG
        REGISTER_STATIC_ARCHIVER(HOG);
    #endif
    #if PHYSFS_SUPPORTS_MVL
        REGISTER_STATIC_ARCHIVER(MVL);
    #endif
    #if PHYSFS_SUPPORTS_WAD
        REGISTER_STATIC_ARCHIVER(WAD);
    #endif
    #if PHYSFS_SUPPORTS_SLB
        REGISTER_STATIC_ARCHIVER(SLB);
    #endif
    #if PHYSFS_SUPPORTS_ISO9660
        REGISTER_STATIC_ARCHIVER(ISO9660);
    #endif

    #undef REGISTER_STATIC_ARCHIVER

    return 1;
} /* initStaticArchivers */


static void setDefaultAllocator(void);
static int doDeinit(void);

int PHYSFS_init(const char *argv0)
{
    BAIL_IF_MACRO(initialized, PHYSFS_ERR_IS_INITIALIZED, 0);

    if (!externalAllocator)
        setDefaultAllocator();

    if ((allocator.Init != NULL) && (!allocator.Init())) return 0;

    if (!__PHYSFS_platformInit())
    {
        if (allocator.Deinit != NULL) allocator.Deinit();
        return 0;
    } /* if */

    /* everything below here can be cleaned up safely by doDeinit(). */

    if (!initializeMutexes()) goto initFailed;

    baseDir = calculateBaseDir(argv0);
    if (!baseDir) goto initFailed;

    userDir = __PHYSFS_platformCalcUserDir();
    if (!userDir) goto initFailed;

    /* Platform layer is required to append a dirsep. */
    assert(baseDir[strlen(baseDir) - 1] == __PHYSFS_platformDirSeparator);
    assert(userDir[strlen(userDir) - 1] == __PHYSFS_platformDirSeparator);

    if (!initStaticArchivers()) goto initFailed;

    initialized = 1;

    /* This makes sure that the error subsystem is initialized. */
    PHYSFS_setErrorCode(PHYSFS_getLastErrorCode());

    return 1;

initFailed:
    doDeinit();
    return 0;
} /* PHYSFS_init */


/* MAKE SURE you hold stateLock before calling this! */
static int closeFileHandleList(FileHandle **list)
{
    FileHandle *i;
    FileHandle *next = NULL;

    for (i = *list; i != NULL; i = next)
    {
        PHYSFS_Io *io = i->io;
        next = i->next;

        if (io->flush && !io->flush(io))
        {
            *list = i;
            return 0;
        } /* if */

        io->destroy(io);
        allocator.Free(i);
    } /* for */

    *list = NULL;
    return 1;
} /* closeFileHandleList */


/* MAKE SURE you hold the stateLock before calling this! */
static void freeSearchPath(void)
{
    DirHandle *i;
    DirHandle *next = NULL;

    closeFileHandleList(&openReadList);

    if (searchPath != NULL)
    {
        for (i = searchPath; i != NULL; i = next)
        {
            next = i->next;
            freeDirHandle(i, openReadList);
        } /* for */
        searchPath = NULL;
    } /* if */
} /* freeSearchPath */


/* MAKE SURE you hold stateLock before calling this! */
static int archiverInUse(const PHYSFS_Archiver *arc, const DirHandle *list)
{
    const DirHandle *i;
    for (i = list; i != NULL; i = i->next)
    {
        if (i->funcs == arc)
            return 1;
    } /* for */

    return 0;  /* not in use */
} /* archiverInUse */


/* MAKE SURE you hold stateLock before calling this! */
static int doDeregisterArchiver(const size_t idx)
{
    const size_t len = (numArchivers - idx) * sizeof (void *);
    const PHYSFS_ArchiveInfo *info = archiveInfo[idx];
    const PHYSFS_Archiver *arc = archivers[idx];

    /* make sure nothing is still using this archiver */
    if (archiverInUse(arc, searchPath) || archiverInUse(arc, writeDir))
        BAIL_MACRO(PHYSFS_ERR_FILES_STILL_OPEN, 0);

    allocator.Free((void *) info->extension);
    allocator.Free((void *) info->description);
    allocator.Free((void *) info->author);
    allocator.Free((void *) info->url);
    allocator.Free((void *) arc);

    memmove(&archiveInfo[idx], &archiveInfo[idx+1], len);
    memmove(&archivers[idx], &archivers[idx+1], len);

    assert(numArchivers > 0);
    numArchivers--;

    return 1;
} /* doDeregisterArchiver */


/* Does NOT hold the state lock; we're shutting down. */
static void freeArchivers(void)
{
    while (numArchivers > 0)
    {
        if (!doDeregisterArchiver(numArchivers - 1))
            assert(!"nothing should be mounted during shutdown.");
    } /* while */

    allocator.Free(archivers);
    allocator.Free(archiveInfo);
    archivers = NULL;
    archiveInfo = NULL;
} /* freeArchivers */


static int doDeinit(void)
{
    closeFileHandleList(&openWriteList);
    BAIL_IF_MACRO(!PHYSFS_setWriteDir(NULL), PHYSFS_ERR_FILES_STILL_OPEN, 0);

    freeSearchPath();
    freeArchivers();
    freeErrorStates();

    if (baseDir != NULL)
    {
        allocator.Free(baseDir);
        baseDir = NULL;
    } /* if */

    if (userDir != NULL)
    {
        allocator.Free(userDir);
        userDir = NULL;
    } /* if */

    if (prefDir != NULL)
    {
        allocator.Free(prefDir);
        prefDir = NULL;
    } /* if */

    if (archiveInfo != NULL)
    {
        allocator.Free(archiveInfo);
        archiveInfo = NULL;
    } /* if */

    if (archivers != NULL)
    {
        allocator.Free(archivers);
        archivers = NULL;
    } /* if */

    allowSymLinks = 0;
    initialized = 0;

    if (errorLock) __PHYSFS_platformDestroyMutex(errorLock);
    if (stateLock) __PHYSFS_platformDestroyMutex(stateLock);

    if (allocator.Deinit != NULL)
        allocator.Deinit();

    errorLock = stateLock = NULL;

    /* !!! FIXME: what on earth are you supposed to do if this fails? */
    BAIL_IF_MACRO(!__PHYSFS_platformDeinit(), ERRPASS, 0);

    return 1;
} /* doDeinit */


int PHYSFS_deinit(void)
{
    BAIL_IF_MACRO(!initialized, PHYSFS_ERR_NOT_INITIALIZED, 0);
    return doDeinit();
} /* PHYSFS_deinit */


int PHYSFS_isInit(void)
{
    return initialized;
} /* PHYSFS_isInit */


char *__PHYSFS_strdup(const char *str)
{
    char *retval = (char *) allocator.Malloc(strlen(str) + 1);
    if (retval)
        strcpy(retval, str);
    return retval;
} /* __PHYSFS_strdup */


PHYSFS_uint32 __PHYSFS_hashString(const char *str, size_t len)
{
    PHYSFS_uint32 hash = 5381;
    while (len--)
        hash = ((hash << 5) + hash) ^ *(str++);
    return hash;
} /* __PHYSFS_hashString */


/* MAKE SURE you hold stateLock before calling this! */
static int doRegisterArchiver(const PHYSFS_Archiver *_archiver)
{
    const PHYSFS_uint32 maxver = CURRENT_PHYSFS_ARCHIVER_API_VERSION;
    const size_t len = (numArchivers + 2) * sizeof (void *);
    PHYSFS_Archiver *archiver = NULL;
    PHYSFS_ArchiveInfo *info = NULL;
    const char *ext = NULL;
    void *ptr = NULL;
    size_t i;

    BAIL_IF_MACRO(!_archiver, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(_archiver->version > maxver, PHYSFS_ERR_UNSUPPORTED, 0);
    BAIL_IF_MACRO(!_archiver->info.extension, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->info.description, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->info.author, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->info.url, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->openArchive, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->enumerateFiles, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->openRead, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->openWrite, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->openAppend, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->remove, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->mkdir, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->closeArchive, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!_archiver->stat, PHYSFS_ERR_INVALID_ARGUMENT, 0);

    ext = _archiver->info.extension;
    for (i = 0; i < numArchivers; i++)
    {
        if (__PHYSFS_utf8stricmp(archiveInfo[i]->extension, ext) == 0)
            BAIL_MACRO(PHYSFS_ERR_DUPLICATE, 0);  /* !!! FIXME: better error? ERR_IN_USE? */
    } /* for */

    /* make a copy of the data. */
    archiver = (PHYSFS_Archiver *) allocator.Malloc(sizeof (*archiver));
    GOTO_IF_MACRO(!archiver, PHYSFS_ERR_OUT_OF_MEMORY, regfailed);

    /* Must copy sizeof (OLD_VERSION_OF_STRUCT) when version changes! */
    memcpy(archiver, _archiver, sizeof (*archiver));

    info = (PHYSFS_ArchiveInfo *) &archiver->info;
    memset(info, '\0', sizeof (*info));  /* NULL in case an alloc fails. */
    #define CPYSTR(item) \
        info->item = __PHYSFS_strdup(_archiver->info.item); \
        GOTO_IF_MACRO(!info->item, PHYSFS_ERR_OUT_OF_MEMORY, regfailed);
    CPYSTR(extension);
    CPYSTR(description);
    CPYSTR(author);
    CPYSTR(url);
    info->supportsSymlinks = _archiver->info.supportsSymlinks;
    #undef CPYSTR

    ptr = allocator.Realloc(archiveInfo, len);
    GOTO_IF_MACRO(!ptr, PHYSFS_ERR_OUT_OF_MEMORY, regfailed);
    archiveInfo = (const PHYSFS_ArchiveInfo **) ptr;

    ptr = allocator.Realloc(archivers, len);
    GOTO_IF_MACRO(!ptr, PHYSFS_ERR_OUT_OF_MEMORY, regfailed);
    archivers = (const PHYSFS_Archiver **) ptr;

    archiveInfo[numArchivers] = info;
    archiveInfo[numArchivers + 1] = NULL;

    archivers[numArchivers] = archiver;
    archivers[numArchivers + 1] = NULL;

    numArchivers++;

    return 1;

regfailed:
    if (info != NULL)
    {
        allocator.Free((void *) info->extension);
        allocator.Free((void *) info->description);
        allocator.Free((void *) info->author);
        allocator.Free((void *) info->url);
    } /* if */
    allocator.Free(archiver);

    return 0;
} /* doRegisterArchiver */


int PHYSFS_registerArchiver(const PHYSFS_Archiver *archiver)
{
    int retval;
    BAIL_IF_MACRO(!initialized, PHYSFS_ERR_NOT_INITIALIZED, 0);
    __PHYSFS_platformGrabMutex(stateLock);
    retval = doRegisterArchiver(archiver);
    __PHYSFS_platformReleaseMutex(stateLock);
    return retval;
} /* PHYSFS_registerArchiver */


int PHYSFS_deregisterArchiver(const char *ext)
{
    size_t i;

    BAIL_IF_MACRO(!initialized, PHYSFS_ERR_NOT_INITIALIZED, 0);
    BAIL_IF_MACRO(!ext, PHYSFS_ERR_INVALID_ARGUMENT, 0);

    __PHYSFS_platformGrabMutex(stateLock);
    for (i = 0; i < numArchivers; i++)
    {
        if (__PHYSFS_utf8stricmp(archiveInfo[i]->extension, ext) == 0)
        {
            const int retval = doDeregisterArchiver(i);
            __PHYSFS_platformReleaseMutex(stateLock);
            return retval;
        } /* if */
    } /* for */
    __PHYSFS_platformReleaseMutex(stateLock);

    BAIL_MACRO(PHYSFS_ERR_NOT_FOUND, 0);
} /* PHYSFS_deregisterArchiver */


const PHYSFS_ArchiveInfo **PHYSFS_supportedArchiveTypes(void)
{
    BAIL_IF_MACRO(!initialized, PHYSFS_ERR_NOT_INITIALIZED, NULL);
    return archiveInfo;
} /* PHYSFS_supportedArchiveTypes */


void PHYSFS_freeList(void *list)
{
    void **i;
    if (list != NULL)
    {
        for (i = (void **) list; *i != NULL; i++)
            allocator.Free(*i);

        allocator.Free(list);
    } /* if */
} /* PHYSFS_freeList */


const char *PHYSFS_getDirSeparator(void)
{
    static char retval[2] = { __PHYSFS_platformDirSeparator, '\0' };
    return retval;
} /* PHYSFS_getDirSeparator */


char **PHYSFS_getCdRomDirs(void)
{
    return doEnumStringList(__PHYSFS_platformDetectAvailableCDs);
} /* PHYSFS_getCdRomDirs */


void PHYSFS_getCdRomDirsCallback(PHYSFS_StringCallback callback, void *data)
{
    __PHYSFS_platformDetectAvailableCDs(callback, data);
} /* PHYSFS_getCdRomDirsCallback */


const char *PHYSFS_getPrefDir(const char *org, const char *app)
{
    const char dirsep = __PHYSFS_platformDirSeparator;
    PHYSFS_Stat statbuf;
    char *ptr = NULL;
    char *endstr = NULL;

    BAIL_IF_MACRO(!initialized, PHYSFS_ERR_NOT_INITIALIZED, 0);
    BAIL_IF_MACRO(!org, PHYSFS_ERR_INVALID_ARGUMENT, NULL);
    BAIL_IF_MACRO(*org == '\0', PHYSFS_ERR_INVALID_ARGUMENT, NULL);
    BAIL_IF_MACRO(!app, PHYSFS_ERR_INVALID_ARGUMENT, NULL);
    BAIL_IF_MACRO(*app == '\0', PHYSFS_ERR_INVALID_ARGUMENT, NULL);

    allocator.Free(prefDir);
    prefDir = __PHYSFS_platformCalcPrefDir(org, app);
    BAIL_IF_MACRO(!prefDir, ERRPASS, NULL);

    assert(strlen(prefDir) > 0);
    endstr = prefDir + (strlen(prefDir) - 1);
    assert(*endstr == dirsep);
    *endstr = '\0';  /* mask out the final dirsep for now. */

    if (!__PHYSFS_platformStat(prefDir, &statbuf))
    {
        for (ptr = strchr(prefDir, dirsep); ptr; ptr = strchr(ptr+1, dirsep))
        {
            *ptr = '\0';
            __PHYSFS_platformMkDir(prefDir);
            *ptr = dirsep;
        } /* for */

        if (!__PHYSFS_platformMkDir(prefDir))
        {
            allocator.Free(prefDir);
            prefDir = NULL;
        } /* if */
    } /* if */

    *endstr = dirsep;  /* readd the final dirsep. */

    return prefDir;
} /* PHYSFS_getPrefDir */


const char *PHYSFS_getBaseDir(void)
{
    return baseDir;   /* this is calculated in PHYSFS_init()... */
} /* PHYSFS_getBaseDir */


const char *__PHYSFS_getUserDir(void)  /* not deprecated internal version. */
{
    return userDir;   /* this is calculated in PHYSFS_init()... */
} /* __PHYSFS_getUserDir */


const char *PHYSFS_getUserDir(void)
{
    return __PHYSFS_getUserDir();
} /* PHYSFS_getUserDir */


const char *PHYSFS_getWriteDir(void)
{
    const char *retval = NULL;

    __PHYSFS_platformGrabMutex(stateLock);
    if (writeDir != NULL)
        retval = writeDir->dirName;
    __PHYSFS_platformReleaseMutex(stateLock);

    return retval;
} /* PHYSFS_getWriteDir */


int PHYSFS_setWriteDir(const char *newDir)
{
    int retval = 1;

    __PHYSFS_platformGrabMutex(stateLock);

    if (writeDir != NULL)
    {
        BAIL_IF_MACRO_MUTEX(!freeDirHandle(writeDir, openWriteList), ERRPASS,
                            stateLock, 0);
        writeDir = NULL;
    } /* if */

    if (newDir != NULL)
    {
        /* !!! FIXME: PHYSFS_Io shouldn't be NULL */
        writeDir = createDirHandle(NULL, newDir, NULL, 1);
        retval = (writeDir != NULL);
    } /* if */

    __PHYSFS_platformReleaseMutex(stateLock);

    return retval;
} /* PHYSFS_setWriteDir */


static int doMount(PHYSFS_Io *io, const char *fname,
                   const char *mountPoint, int appendToPath)
{
    DirHandle *dh;
    DirHandle *prev = NULL;
    DirHandle *i;

    if (mountPoint == NULL)
        mountPoint = "/";

    __PHYSFS_platformGrabMutex(stateLock);

    if (fname != NULL)
    {
        for (i = searchPath; i != NULL; i = i->next)
        {
            /* already in search path? */
            if ((i->dirName != NULL) && (strcmp(fname, i->dirName) == 0))
                BAIL_MACRO_MUTEX(ERRPASS, stateLock, 1);
            prev = i;
        } /* for */
    } /* if */

    dh = createDirHandle(io, fname, mountPoint, 0);
    BAIL_IF_MACRO_MUTEX(!dh, ERRPASS, stateLock, 0);

    if (appendToPath)
    {
        if (prev == NULL)
            searchPath = dh;
        else
            prev->next = dh;
    } /* if */
    else
    {
        dh->next = searchPath;
        searchPath = dh;
    } /* else */

    __PHYSFS_platformReleaseMutex(stateLock);
    return 1;
} /* doMount */


int PHYSFS_mountIo(PHYSFS_Io *io, const char *fname,
                   const char *mountPoint, int appendToPath)
{
    BAIL_IF_MACRO(!io, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(io->version != 0, PHYSFS_ERR_UNSUPPORTED, 0);
    return doMount(io, fname, mountPoint, appendToPath);
} /* PHYSFS_mountIo */


int PHYSFS_mountMemory(const void *buf, PHYSFS_uint64 len, void (*del)(void *),
                       const char *fname, const char *mountPoint,
                       int appendToPath)
{
    int retval = 0;
    PHYSFS_Io *io = NULL;

    BAIL_IF_MACRO(!buf, PHYSFS_ERR_INVALID_ARGUMENT, 0);

    io = __PHYSFS_createMemoryIo(buf, len, del);
    BAIL_IF_MACRO(!io, ERRPASS, 0);
    retval = doMount(io, fname, mountPoint, appendToPath);
    if (!retval)
    {
        /* docs say not to call (del) in case of failure, so cheat. */
        MemoryIoInfo *info = (MemoryIoInfo *) io->opaque;
        info->destruct = NULL;
        io->destroy(io);
    } /* if */

    return retval;
} /* PHYSFS_mountMemory */


int PHYSFS_mountHandle(PHYSFS_File *file, const char *fname,
                       const char *mountPoint, int appendToPath)
{
    int retval = 0;
    PHYSFS_Io *io = NULL;

    BAIL_IF_MACRO(file == NULL, PHYSFS_ERR_INVALID_ARGUMENT, 0);

    io = __PHYSFS_createHandleIo(file);
    BAIL_IF_MACRO(!io, ERRPASS, 0);
    retval = doMount(io, fname, mountPoint, appendToPath);
    if (!retval)
    {
        /* docs say not to destruct in case of failure, so cheat. */
        io->opaque = NULL;
        io->destroy(io);
    } /* if */

    return retval;
} /* PHYSFS_mountHandle */


int PHYSFS_mount(const char *newDir, const char *mountPoint, int appendToPath)
{
    BAIL_IF_MACRO(!newDir, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    return doMount(NULL, newDir, mountPoint, appendToPath);
} /* PHYSFS_mount */


int PHYSFS_addToSearchPath(const char *newDir, int appendToPath)
{
    return doMount(NULL, newDir, NULL, appendToPath);
} /* PHYSFS_addToSearchPath */


int PHYSFS_removeFromSearchPath(const char *oldDir)
{
    return PHYSFS_unmount(oldDir);
} /* PHYSFS_removeFromSearchPath */


int PHYSFS_unmount(const char *oldDir)
{
    DirHandle *i;
    DirHandle *prev = NULL;
    DirHandle *next = NULL;

    BAIL_IF_MACRO(oldDir == NULL, PHYSFS_ERR_INVALID_ARGUMENT, 0);

    __PHYSFS_platformGrabMutex(stateLock);
    for (i = searchPath; i != NULL; i = i->next)
    {
        if (strcmp(i->dirName, oldDir) == 0)
        {
            next = i->next;
            BAIL_IF_MACRO_MUTEX(!freeDirHandle(i, openReadList), ERRPASS,
                                stateLock, 0);

            if (prev == NULL)
                searchPath = next;
            else
                prev->next = next;

            BAIL_MACRO_MUTEX(ERRPASS, stateLock, 1);
        } /* if */
        prev = i;
    } /* for */

    BAIL_MACRO_MUTEX(PHYSFS_ERR_NOT_MOUNTED, stateLock, 0);
} /* PHYSFS_unmount */


char **PHYSFS_getSearchPath(void)
{
    return doEnumStringList(PHYSFS_getSearchPathCallback);
} /* PHYSFS_getSearchPath */


const char *PHYSFS_getMountPoint(const char *dir)
{
    DirHandle *i;
    __PHYSFS_platformGrabMutex(stateLock);
    for (i = searchPath; i != NULL; i = i->next)
    {
        if (strcmp(i->dirName, dir) == 0)
        {
            const char *retval = ((i->mountPoint) ? i->mountPoint : "/");
            __PHYSFS_platformReleaseMutex(stateLock);
            return retval;
        } /* if */
    } /* for */
    __PHYSFS_platformReleaseMutex(stateLock);

    BAIL_MACRO(PHYSFS_ERR_NOT_MOUNTED, NULL);
} /* PHYSFS_getMountPoint */


void PHYSFS_getSearchPathCallback(PHYSFS_StringCallback callback, void *data)
{
    DirHandle *i;

    __PHYSFS_platformGrabMutex(stateLock);

    for (i = searchPath; i != NULL; i = i->next)
        callback(data, i->dirName);

    __PHYSFS_platformReleaseMutex(stateLock);
} /* PHYSFS_getSearchPathCallback */


/* Split out to avoid stack allocation in a loop. */
static void setSaneCfgAddPath(const char *i, const size_t l, const char *dirsep,
                              int archivesFirst)
{
    const char *d = PHYSFS_getRealDir(i);
    const size_t allocsize = strlen(d) + strlen(dirsep) + l + 1;
    char *str = (char *) __PHYSFS_smallAlloc(allocsize);
    if (str != NULL)
    {
        sprintf(str, "%s%s%s", d, dirsep, i);
        PHYSFS_mount(str, NULL, archivesFirst == 0);
        __PHYSFS_smallFree(str);
    } /* if */
} /* setSaneCfgAddPath */


int PHYSFS_setSaneConfig(const char *organization, const char *appName,
                         const char *archiveExt, int includeCdRoms,
                         int archivesFirst)
{
    const char *dirsep = PHYSFS_getDirSeparator();
    const char *basedir;
    const char *prefdir;

    BAIL_IF_MACRO(!initialized, PHYSFS_ERR_NOT_INITIALIZED, 0);

    prefdir = PHYSFS_getPrefDir(organization, appName);
    BAIL_IF_MACRO(!prefdir, ERRPASS, 0);

    basedir = PHYSFS_getBaseDir();
    BAIL_IF_MACRO(!basedir, ERRPASS, 0);

    BAIL_IF_MACRO(!PHYSFS_setWriteDir(prefdir), PHYSFS_ERR_NO_WRITE_DIR, 0);

    /* Put write dir first in search path... */
    PHYSFS_mount(prefdir, NULL, 0);

    /* Put base path on search path... */
    PHYSFS_mount(basedir, NULL, 1);

    /* handle CD-ROMs... */
    if (includeCdRoms)
    {
        char **cds = PHYSFS_getCdRomDirs();
        char **i;
        for (i = cds; *i != NULL; i++)
            PHYSFS_mount(*i, NULL, 1);
        PHYSFS_freeList(cds);
    } /* if */

    /* Root out archives, and add them to search path... */
    if (archiveExt != NULL)
    {
        char **rc = PHYSFS_enumerateFiles("/");
        char **i;
        size_t extlen = strlen(archiveExt);
        char *ext;

        for (i = rc; *i != NULL; i++)
        {
            size_t l = strlen(*i);
            if ((l > extlen) && ((*i)[l - extlen - 1] == '.'))
            {
                ext = (*i) + (l - extlen);
                if (__PHYSFS_utf8stricmp(ext, archiveExt) == 0)
                    setSaneCfgAddPath(*i, l, dirsep, archivesFirst);
            } /* if */
        } /* for */

        PHYSFS_freeList(rc);
    } /* if */

    return 1;
} /* PHYSFS_setSaneConfig */


void PHYSFS_permitSymbolicLinks(int allow)
{
    allowSymLinks = allow;
} /* PHYSFS_permitSymbolicLinks */


int PHYSFS_symbolicLinksPermitted(void)
{
    return allowSymLinks;
} /* PHYSFS_symbolicLinksPermitted */


/*
 * Verify that (fname) (in platform-independent notation), in relation
 *  to (h) is secure. That means that each element of fname is checked
 *  for symlinks (if they aren't permitted). This also allows for quick
 *  rejection of files that exist outside an archive's mountpoint.
 *
 * With some exceptions (like PHYSFS_mkdir(), which builds multiple subdirs
 *  at a time), you should always pass zero for "allowMissing" for efficiency.
 *
 * (fname) must point to an output from sanitizePlatformIndependentPath(),
 *  since it will make sure that path names are in the right format for
 *  passing certain checks. It will also do checks for "insecure" pathnames
 *  like ".." which should be done once instead of once per archive. This also
 *  gives us license to treat (fname) as scratch space in this function.
 *
 * Returns non-zero if string is safe, zero if there's a security issue.
 *  PHYSFS_getLastError() will specify what was wrong. (*fname) will be
 *  updated to point past any mount point elements so it is prepared to
 *  be used with the archiver directly.
 */
static int verifyPath(DirHandle *h, char **_fname, int allowMissing)
{
    char *fname = *_fname;
    int retval = 1;
    char *start;
    char *end;

    if (*fname == '\0')  /* quick rejection. */
        return 1;

    /* !!! FIXME: This codeblock sucks. */
    if (h->mountPoint != NULL)  /* NULL mountpoint means "/". */
    {
        size_t mntpntlen = strlen(h->mountPoint);
        size_t len = strlen(fname);
        assert(mntpntlen > 1); /* root mount points should be NULL. */
        /* not under the mountpoint, so skip this archive. */
        BAIL_IF_MACRO(len < mntpntlen-1, PHYSFS_ERR_NOT_FOUND, 0);
        /* !!! FIXME: Case insensitive? */
        retval = strncmp(h->mountPoint, fname, mntpntlen-1);
        BAIL_IF_MACRO(retval != 0, PHYSFS_ERR_NOT_FOUND, 0);
        if (len > mntpntlen-1)  /* corner case... */
            BAIL_IF_MACRO(fname[mntpntlen-1]!='/', PHYSFS_ERR_NOT_FOUND, 0);
        fname += mntpntlen-1;  /* move to start of actual archive path. */
        if (*fname == '/')
            fname++;
        *_fname = fname;  /* skip mountpoint for later use. */
        retval = 1;  /* may be reset, below. */
    } /* if */

    start = fname;
    if (!allowSymLinks)
    {
        while (1)
        {
            PHYSFS_Stat statbuf;
            int rc = 0;
            end = strchr(start, '/');

            if (end != NULL) *end = '\0';
            rc = h->funcs->stat(h->opaque, fname, &statbuf);
            if (rc)
                rc = (statbuf.filetype == PHYSFS_FILETYPE_SYMLINK);
            else if (currentErrorCode() == PHYSFS_ERR_NOT_FOUND)
                retval = 0;

            if (end != NULL) *end = '/';

            /* insecure path (has a disallowed symlink in it)? */
            BAIL_IF_MACRO(rc, PHYSFS_ERR_SYMLINK_FORBIDDEN, 0);

            /* break out early if path element is missing. */
            if (!retval)
            {
                /*
                 * We need to clear it if it's the last element of the path,
                 *  since this might be a non-existant file we're opening
                 *  for writing...
                 */
                if ((end == NULL) || (allowMissing))
                    retval = 1;
                break;
            } /* if */

            if (end == NULL)
                break;

            start = end + 1;
        } /* while */
    } /* if */

    return retval;
} /* verifyPath */


static int doMkdir(const char *_dname, char *dname)
{
    DirHandle *h;
    char *start;
    char *end;
    int retval = 0;
    int exists = 1;  /* force existance check on first path element. */

    BAIL_IF_MACRO(!sanitizePlatformIndependentPath(_dname, dname), ERRPASS, 0);

    __PHYSFS_platformGrabMutex(stateLock);
    BAIL_IF_MACRO_MUTEX(!writeDir, PHYSFS_ERR_NO_WRITE_DIR, stateLock, 0);
    h = writeDir;
    BAIL_IF_MACRO_MUTEX(!verifyPath(h, &dname, 1), ERRPASS, stateLock, 0);

    start = dname;
    while (1)
    {
        end = strchr(start, '/');
        if (end != NULL)
            *end = '\0';

        /* only check for existance if all parent dirs existed, too... */
        if (exists)
        {
            PHYSFS_Stat statbuf;
            const int rc = h->funcs->stat(h->opaque, dname, &statbuf);
            if ((!rc) && (currentErrorCode() == PHYSFS_ERR_NOT_FOUND))
                exists = 0;
            retval = ((rc) && (statbuf.filetype == PHYSFS_FILETYPE_DIRECTORY));
        } /* if */

        if (!exists)
            retval = h->funcs->mkdir(h->opaque, dname);

        if (!retval)
            break;

        if (end == NULL)
            break;

        *end = '/';
        start = end + 1;
    } /* while */

    __PHYSFS_platformReleaseMutex(stateLock);
    return retval;
} /* doMkdir */


int PHYSFS_mkdir(const char *_dname)
{
    int retval = 0;
    char *dname;
    size_t len;

    BAIL_IF_MACRO(!_dname, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    len = strlen(_dname) + 1;
    dname = (char *) __PHYSFS_smallAlloc(len);
    BAIL_IF_MACRO(!dname, PHYSFS_ERR_OUT_OF_MEMORY, 0);
    retval = doMkdir(_dname, dname);
    __PHYSFS_smallFree(dname);
    return retval;
} /* PHYSFS_mkdir */


static int doDelete(const char *_fname, char *fname)
{
    int retval;
    DirHandle *h;
    BAIL_IF_MACRO(!sanitizePlatformIndependentPath(_fname, fname), ERRPASS, 0);

    __PHYSFS_platformGrabMutex(stateLock);

    BAIL_IF_MACRO_MUTEX(!writeDir, PHYSFS_ERR_NO_WRITE_DIR, stateLock, 0);
    h = writeDir;
    BAIL_IF_MACRO_MUTEX(!verifyPath(h, &fname, 0), ERRPASS, stateLock, 0);
    retval = h->funcs->remove(h->opaque, fname);

    __PHYSFS_platformReleaseMutex(stateLock);
    return retval;
} /* doDelete */


int PHYSFS_delete(const char *_fname)
{
    int retval;
    char *fname;
    size_t len;

    BAIL_IF_MACRO(!_fname, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    len = strlen(_fname) + 1;
    fname = (char *) __PHYSFS_smallAlloc(len);
    BAIL_IF_MACRO(!fname, PHYSFS_ERR_OUT_OF_MEMORY, 0);
    retval = doDelete(_fname, fname);
    __PHYSFS_smallFree(fname);
    return retval;
} /* PHYSFS_delete */


const char *PHYSFS_getRealDir(const char *_fname)
{
    const char *retval = NULL;
    char *fname = NULL;
    size_t len;

    BAIL_IF_MACRO(!_fname, PHYSFS_ERR_INVALID_ARGUMENT, NULL);
    len = strlen(_fname) + 1;
    fname = __PHYSFS_smallAlloc(len);
    BAIL_IF_MACRO(!fname, PHYSFS_ERR_OUT_OF_MEMORY, NULL);
    if (sanitizePlatformIndependentPath(_fname, fname))
    {
        DirHandle *i;
        __PHYSFS_platformGrabMutex(stateLock);
        for (i = searchPath; i != NULL; i = i->next)
        {
            char *arcfname = fname;
            if (partOfMountPoint(i, arcfname))
            {
                retval = i->dirName;
                break;
            } /* if */
            else if (verifyPath(i, &arcfname, 0))
            {
                PHYSFS_Stat statbuf;
                if (i->funcs->stat(i->opaque, arcfname, &statbuf))
                {
                    retval = i->dirName;
                    break;
                } /* if */
            } /* if */
        } /* for */
        __PHYSFS_platformReleaseMutex(stateLock);
    } /* if */

    __PHYSFS_smallFree(fname);
    return retval;
} /* PHYSFS_getRealDir */


static int locateInStringList(const char *str,
                              char **list,
                              PHYSFS_uint32 *pos)
{
    PHYSFS_uint32 len = *pos;
    PHYSFS_uint32 half_len;
    PHYSFS_uint32 lo = 0;
    PHYSFS_uint32 middle;
    int cmp;

    while (len > 0)
    {
        half_len = len >> 1;
        middle = lo + half_len;
        cmp = strcmp(list[middle], str);

        if (cmp == 0)  /* it's in the list already. */
            return 1;
        else if (cmp > 0)
            len = half_len;
        else
        {
            lo = middle + 1;
            len -= half_len + 1;
        } /* else */
    } /* while */

    *pos = lo;
    return 0;
} /* locateInStringList */


static void enumFilesCallback(void *data, const char *origdir, const char *str)
{
    PHYSFS_uint32 pos;
    void *ptr;
    char *newstr;
    EnumStringListCallbackData *pecd = (EnumStringListCallbackData *) data;

    /*
     * See if file is in the list already, and if not, insert it in there
     *  alphabetically...
     */
    pos = pecd->size;
    if (locateInStringList(str, pecd->list, &pos))
        return;  /* already in the list. */

    ptr = allocator.Realloc(pecd->list, (pecd->size + 2) * sizeof (char *));
    newstr = (char *) allocator.Malloc(strlen(str) + 1);
    if (ptr != NULL)
        pecd->list = (char **) ptr;

    if ((ptr == NULL) || (newstr == NULL))
        return;  /* better luck next time. */

    strcpy(newstr, str);

    if (pos != pecd->size)
    {
        memmove(&pecd->list[pos+1], &pecd->list[pos],
                 sizeof (char *) * ((pecd->size) - pos));
    } /* if */

    pecd->list[pos] = newstr;
    pecd->size++;
} /* enumFilesCallback */


char **PHYSFS_enumerateFiles(const char *path)
{
    EnumStringListCallbackData ecd;
    memset(&ecd, '\0', sizeof (ecd));
    ecd.list = (char **) allocator.Malloc(sizeof (char *));
    BAIL_IF_MACRO(!ecd.list, PHYSFS_ERR_OUT_OF_MEMORY, NULL);
    PHYSFS_enumerateFilesCallback(path, enumFilesCallback, &ecd);
    ecd.list[ecd.size] = NULL;
    return ecd.list;
} /* PHYSFS_enumerateFiles */


/*
 * Broke out to seperate function so we can use stack allocation gratuitously.
 */
static void enumerateFromMountPoint(DirHandle *i, const char *arcfname,
                                    PHYSFS_EnumFilesCallback callback,
                                    const char *_fname, void *data)
{
    const size_t len = strlen(arcfname);
    char *ptr = NULL;
    char *end = NULL;
    const size_t slen = strlen(i->mountPoint) + 1;
    char *mountPoint = (char *) __PHYSFS_smallAlloc(slen);

    if (mountPoint == NULL)
        return;  /* oh well. */

    strcpy(mountPoint, i->mountPoint);
    ptr = mountPoint + ((len) ? len + 1 : 0);
    end = strchr(ptr, '/');
    assert(end);  /* should always find a terminating '/'. */
    *end = '\0';
    callback(data, _fname, ptr);
    __PHYSFS_smallFree(mountPoint);
} /* enumerateFromMountPoint */


typedef struct SymlinkFilterData
{
    PHYSFS_EnumFilesCallback callback;
    void *callbackData;
    DirHandle *dirhandle;
} SymlinkFilterData;

/* !!! FIXME: broken if in a virtual mountpoint (stat call fails). */
static void enumCallbackFilterSymLinks(void *_data, const char *origdir,
                                       const char *fname)
{
    const char *trimmedDir = (*origdir == '/') ? (origdir+1) : origdir;
    const size_t slen = strlen(trimmedDir) + strlen(fname) + 2;
    char *path = (char *) __PHYSFS_smallAlloc(slen);

    if (path != NULL)
    {
        SymlinkFilterData *data = (SymlinkFilterData *) _data;
        const DirHandle *dh = data->dirhandle;
        PHYSFS_Stat statbuf;

        sprintf(path, "%s%s%s", trimmedDir, *trimmedDir ? "/" : "", fname);
        if (dh->funcs->stat(dh->opaque, path, &statbuf))
        {
            /* Pass it on to the application if it's not a symlink. */
            if (statbuf.filetype != PHYSFS_FILETYPE_SYMLINK)
                data->callback(data->callbackData, origdir, fname);
        } /* if */

        __PHYSFS_smallFree(path);
    } /* if */
} /* enumCallbackFilterSymLinks */


/* !!! FIXME: this should report error conditions. */
void PHYSFS_enumerateFilesCallback(const char *_fname,
                                   PHYSFS_EnumFilesCallback callback,
                                   void *data)
{
    size_t len;
    char *fname;

    BAIL_IF_MACRO(!_fname, PHYSFS_ERR_INVALID_ARGUMENT, ) /*0*/;
    BAIL_IF_MACRO(!callback, PHYSFS_ERR_INVALID_ARGUMENT, ) /*0*/;

    len = strlen(_fname) + 1;
    fname = (char *) __PHYSFS_smallAlloc(len);
    BAIL_IF_MACRO(!fname, PHYSFS_ERR_OUT_OF_MEMORY, ) /*0*/;

    if (sanitizePlatformIndependentPath(_fname, fname))
    {
        DirHandle *i;
        SymlinkFilterData filterdata;

        __PHYSFS_platformGrabMutex(stateLock);

        if (!allowSymLinks)
        {
            memset(&filterdata, '\0', sizeof (filterdata));
            filterdata.callback = callback;
            filterdata.callbackData = data;
        } /* if */

        for (i = searchPath; i != NULL; i = i->next)
        {
            char *arcfname = fname;
            if (partOfMountPoint(i, arcfname))
                enumerateFromMountPoint(i, arcfname, callback, _fname, data);

            else if (verifyPath(i, &arcfname, 0))
            {
                if ((!allowSymLinks) && (i->funcs->info.supportsSymlinks))
                {
                    filterdata.dirhandle = i;
                    i->funcs->enumerateFiles(i->opaque, arcfname,
                                             enumCallbackFilterSymLinks,
                                             _fname, &filterdata);
                } /* if */
                else
                {
                    i->funcs->enumerateFiles(i->opaque, arcfname,
                                             callback, _fname, data);
                } /* else */
            } /* else if */
        } /* for */
        __PHYSFS_platformReleaseMutex(stateLock);
    } /* if */

    __PHYSFS_smallFree(fname);
} /* PHYSFS_enumerateFilesCallback */


int PHYSFS_exists(const char *fname)
{
    return (PHYSFS_getRealDir(fname) != NULL);
} /* PHYSFS_exists */


PHYSFS_sint64 PHYSFS_getLastModTime(const char *fname)
{
    PHYSFS_Stat statbuf;
    BAIL_IF_MACRO(!PHYSFS_stat(fname, &statbuf), ERRPASS, -1);
    return statbuf.modtime;
} /* PHYSFS_getLastModTime */


int PHYSFS_isDirectory(const char *fname)
{
    PHYSFS_Stat statbuf;
    BAIL_IF_MACRO(!PHYSFS_stat(fname, &statbuf), ERRPASS, 0);
    return (statbuf.filetype == PHYSFS_FILETYPE_DIRECTORY);
} /* PHYSFS_isDirectory */


int PHYSFS_isSymbolicLink(const char *fname)
{
    PHYSFS_Stat statbuf;
    BAIL_IF_MACRO(!PHYSFS_stat(fname, &statbuf), ERRPASS, 0);
    return (statbuf.filetype == PHYSFS_FILETYPE_SYMLINK);
} /* PHYSFS_isSymbolicLink */


static PHYSFS_File *doOpenWrite(const char *_fname, int appending)
{
    FileHandle *fh = NULL;
    size_t len;
    char *fname;

    BAIL_IF_MACRO(!_fname, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    len = strlen(_fname) + 1;
    fname = (char *) __PHYSFS_smallAlloc(len);
    BAIL_IF_MACRO(!fname, PHYSFS_ERR_OUT_OF_MEMORY, 0);

    if (sanitizePlatformIndependentPath(_fname, fname))
    {
        PHYSFS_Io *io = NULL;
        DirHandle *h = NULL;
        const PHYSFS_Archiver *f;

        __PHYSFS_platformGrabMutex(stateLock);

        GOTO_IF_MACRO(!writeDir, PHYSFS_ERR_NO_WRITE_DIR, doOpenWriteEnd);

        h = writeDir;
        GOTO_IF_MACRO(!verifyPath(h, &fname, 0), ERRPASS, doOpenWriteEnd);

        f = h->funcs;
        if (appending)
            io = f->openAppend(h->opaque, fname);
        else
            io = f->openWrite(h->opaque, fname);

        GOTO_IF_MACRO(!io, ERRPASS, doOpenWriteEnd);

        fh = (FileHandle *) allocator.Malloc(sizeof (FileHandle));
        if (fh == NULL)
        {
            io->destroy(io);
            GOTO_MACRO(PHYSFS_ERR_OUT_OF_MEMORY, doOpenWriteEnd);
        } /* if */
        else
        {
            memset(fh, '\0', sizeof (FileHandle));
            fh->io = io;
            fh->dirHandle = h;
            fh->next = openWriteList;
            openWriteList = fh;
        } /* else */

        doOpenWriteEnd:
        __PHYSFS_platformReleaseMutex(stateLock);
    } /* if */

    __PHYSFS_smallFree(fname);
    return ((PHYSFS_File *) fh);
} /* doOpenWrite */


PHYSFS_File *PHYSFS_openWrite(const char *filename)
{
    return doOpenWrite(filename, 0);
} /* PHYSFS_openWrite */


PHYSFS_File *PHYSFS_openAppend(const char *filename)
{
    return doOpenWrite(filename, 1);
} /* PHYSFS_openAppend */


PHYSFS_File *PHYSFS_openRead(const char *_fname)
{
    FileHandle *fh = NULL;
    char *fname;
    size_t len;

    BAIL_IF_MACRO(!_fname, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    len = strlen(_fname) + 1;
    fname = (char *) __PHYSFS_smallAlloc(len);
    BAIL_IF_MACRO(!fname, PHYSFS_ERR_OUT_OF_MEMORY, 0);

    if (sanitizePlatformIndependentPath(_fname, fname))
    {
        DirHandle *i = NULL;
        PHYSFS_Io *io = NULL;

        __PHYSFS_platformGrabMutex(stateLock);

        GOTO_IF_MACRO(!searchPath, PHYSFS_ERR_NOT_FOUND, openReadEnd);

        for (i = searchPath; i != NULL; i = i->next)
        {
            char *arcfname = fname;
            if (verifyPath(i, &arcfname, 0))
            {
                io = i->funcs->openRead(i->opaque, arcfname);
                if (io)
                    break;
            } /* if */
        } /* for */

        GOTO_IF_MACRO(!io, ERRPASS, openReadEnd);

        fh = (FileHandle *) allocator.Malloc(sizeof (FileHandle));
        if (fh == NULL)
        {
            io->destroy(io);
            GOTO_MACRO(PHYSFS_ERR_OUT_OF_MEMORY, openReadEnd);
        } /* if */

        memset(fh, '\0', sizeof (FileHandle));
        fh->io = io;
        fh->forReading = 1;
        fh->dirHandle = i;
        fh->next = openReadList;
        openReadList = fh;

        openReadEnd:
        __PHYSFS_platformReleaseMutex(stateLock);
    } /* if */

    __PHYSFS_smallFree(fname);
    return ((PHYSFS_File *) fh);
} /* PHYSFS_openRead */


static int closeHandleInOpenList(FileHandle **list, FileHandle *handle)
{
    FileHandle *prev = NULL;
    FileHandle *i;
    int rc = 1;

    for (i = *list; i != NULL; i = i->next)
    {
        if (i == handle)  /* handle is in this list? */
        {
            PHYSFS_Io *io = handle->io;
            PHYSFS_uint8 *tmp = handle->buffer;
            rc = PHYSFS_flush((PHYSFS_File *) handle);
            if (!rc)
                return -1;
            io->destroy(io);

            if (tmp != NULL)  /* free any associated buffer. */
                allocator.Free(tmp);

            if (prev == NULL)
                *list = handle->next;
            else
                prev->next = handle->next;

            allocator.Free(handle);
            return 1;
        } /* if */
        prev = i;
    } /* for */

    return 0;
} /* closeHandleInOpenList */


int PHYSFS_close(PHYSFS_File *_handle)
{
    FileHandle *handle = (FileHandle *) _handle;
    int rc;

    __PHYSFS_platformGrabMutex(stateLock);

    /* -1 == close failure. 0 == not found. 1 == success. */
    rc = closeHandleInOpenList(&openReadList, handle);
    BAIL_IF_MACRO_MUTEX(rc == -1, ERRPASS, stateLock, 0);
    if (!rc)
    {
        rc = closeHandleInOpenList(&openWriteList, handle);
        BAIL_IF_MACRO_MUTEX(rc == -1, ERRPASS, stateLock, 0);
    } /* if */

    __PHYSFS_platformReleaseMutex(stateLock);
    BAIL_IF_MACRO(!rc, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    return 1;
} /* PHYSFS_close */


static PHYSFS_sint64 doBufferedRead(FileHandle *fh, void *buffer,
                                    PHYSFS_uint64 len)
{
    PHYSFS_Io *io = NULL;
    PHYSFS_sint64 retval = 0;
    PHYSFS_uint32 buffered = 0;
    PHYSFS_sint64 rc = 0;

    if (len == 0)
        return 0;

    buffered = fh->buffill - fh->bufpos;
    if (buffered >= len)  /* totally in the buffer, just copy and return! */
    {
        memcpy(buffer, fh->buffer + fh->bufpos, (size_t) len);
        fh->bufpos += (PHYSFS_uint32) len;
        return (PHYSFS_sint64) len;
    } /* if */

    else if (buffered > 0) /* partially in the buffer... */
    {
        memcpy(buffer, fh->buffer + fh->bufpos, (size_t) buffered);
        buffer = ((PHYSFS_uint8 *) buffer) + buffered;
        len -= buffered;
        retval = buffered;
    } /* if */

    /* if you got here, the buffer is drained and we still need bytes. */
    assert(len > 0);

    fh->buffill = fh->bufpos = 0;

    io = fh->io;
    if (len >= fh->bufsize)  /* need more than the buffer takes. */
    {
        /* leave buffer empty, go right to output instead. */
        rc = io->read(io, buffer, len);
        if (rc <= 0)
            return ((retval == 0) ? rc : retval);
        return retval + rc;
    } /* if */

    /* need less than buffer can take. Fill buffer. */
    rc = io->read(io, fh->buffer, fh->bufsize);
    if (rc <= 0)
        return ((retval == 0) ? rc : retval);

    assert(fh->bufpos == 0);
    fh->buffill = (PHYSFS_uint32) rc;
    rc = doBufferedRead(fh, buffer, len);  /* go from the start, again. */
    if (rc <= 0)
        return ((retval == 0) ? rc : retval);

    return retval + rc;
} /* doBufferedRead */


PHYSFS_sint64 PHYSFS_read(PHYSFS_File *handle, void *buffer,
                          PHYSFS_uint32 size, PHYSFS_uint32 count)
{
    const PHYSFS_uint64 len = ((PHYSFS_uint64) size) * ((PHYSFS_uint64) count);
    const PHYSFS_sint64 retval = PHYSFS_readBytes(handle, buffer, len);
    return ( (retval <= 0) ? retval : (retval / ((PHYSFS_sint64) size)) );
} /* PHYSFS_read */


PHYSFS_sint64 PHYSFS_readBytes(PHYSFS_File *handle, void *buffer,
                               PHYSFS_uint64 len)
{
    FileHandle *fh = (FileHandle *) handle;

#ifdef PHYSFS_NO_64BIT_SUPPORT
    const PHYSFS_uint64 maxlen = __PHYSFS_UI64(0x7FFFFFFF);
#else
    const PHYSFS_uint64 maxlen = __PHYSFS_UI64(0x7FFFFFFFFFFFFFFF);
#endif

    if (!__PHYSFS_ui64FitsAddressSpace(len))
        BAIL_MACRO(PHYSFS_ERR_INVALID_ARGUMENT, -1);

    BAIL_IF_MACRO(len > maxlen, PHYSFS_ERR_INVALID_ARGUMENT, -1);
    BAIL_IF_MACRO(!fh->forReading, PHYSFS_ERR_OPEN_FOR_WRITING, -1);
    BAIL_IF_MACRO(len == 0, ERRPASS, 0);
    if (fh->buffer)
        return doBufferedRead(fh, buffer, len);

    return fh->io->read(fh->io, buffer, len);
} /* PHYSFS_readBytes */


static PHYSFS_sint64 doBufferedWrite(PHYSFS_File *handle, const void *buffer,
                                     PHYSFS_uint64 len)
{
    FileHandle *fh = (FileHandle *) handle;

    /* whole thing fits in the buffer? */
    if ( (((PHYSFS_uint64) fh->buffill) + len) < fh->bufsize )
    {
        memcpy(fh->buffer + fh->buffill, buffer, (size_t) len);
        fh->buffill += (PHYSFS_uint32) len;
        return (PHYSFS_sint64) len;
    } /* if */

    /* would overflow buffer. Flush and then write the new objects, too. */
    BAIL_IF_MACRO(!PHYSFS_flush(handle), ERRPASS, -1);
    return fh->io->write(fh->io, buffer, len);
} /* doBufferedWrite */


PHYSFS_sint64 PHYSFS_write(PHYSFS_File *handle, const void *buffer,
                           PHYSFS_uint32 size, PHYSFS_uint32 count)
{
    const PHYSFS_uint64 len = ((PHYSFS_uint64) size) * ((PHYSFS_uint64) count);
    const PHYSFS_sint64 retval = PHYSFS_writeBytes(handle, buffer, len);
    return ( (retval <= 0) ? retval : (retval / ((PHYSFS_sint64) size)) );
} /* PHYSFS_write */


PHYSFS_sint64 PHYSFS_writeBytes(PHYSFS_File *handle, const void *buffer,
                                PHYSFS_uint64 len)
{
    FileHandle *fh = (FileHandle *) handle;

#ifdef PHYSFS_NO_64BIT_SUPPORT
    const PHYSFS_uint64 maxlen = __PHYSFS_UI64(0x7FFFFFFF);
#else
    const PHYSFS_uint64 maxlen = __PHYSFS_UI64(0x7FFFFFFFFFFFFFFF);
#endif

    if (!__PHYSFS_ui64FitsAddressSpace(len))
        BAIL_MACRO(PHYSFS_ERR_INVALID_ARGUMENT, -1);

    BAIL_IF_MACRO(len > maxlen, PHYSFS_ERR_INVALID_ARGUMENT, -1);
    BAIL_IF_MACRO(fh->forReading, PHYSFS_ERR_OPEN_FOR_READING, -1);
    BAIL_IF_MACRO(len == 0, ERRPASS, 0);
    if (fh->buffer)
        return doBufferedWrite(handle, buffer, len);

    return fh->io->write(fh->io, buffer, len);
} /* PHYSFS_write */


int PHYSFS_eof(PHYSFS_File *handle)
{
    FileHandle *fh = (FileHandle *) handle;

    if (!fh->forReading)  /* never EOF on files opened for write/append. */
        return 0;

    /* can't be eof if buffer isn't empty */
    if (fh->bufpos == fh->buffill)
    {
        /* check the Io. */
        PHYSFS_Io *io = fh->io;
        const PHYSFS_sint64 pos = io->tell(io);
        const PHYSFS_sint64 len = io->length(io);
        if ((pos < 0) || (len < 0))
            return 0;  /* beats me. */
        return (pos >= len);
    } /* if */

    return 0;
} /* PHYSFS_eof */


PHYSFS_sint64 PHYSFS_tell(PHYSFS_File *handle)
{
    FileHandle *fh = (FileHandle *) handle;
    const PHYSFS_sint64 pos = fh->io->tell(fh->io);
    const PHYSFS_sint64 retval = fh->forReading ?
                                 (pos - fh->buffill) + fh->bufpos :
                                 (pos + fh->buffill);
    return retval;
} /* PHYSFS_tell */


int PHYSFS_seek(PHYSFS_File *handle, PHYSFS_uint64 pos)
{
    FileHandle *fh = (FileHandle *) handle;
    BAIL_IF_MACRO(!PHYSFS_flush(handle), ERRPASS, 0);

    if (fh->buffer && fh->forReading)
    {
        /* avoid throwing away our precious buffer if seeking within it. */
        PHYSFS_sint64 offset = pos - PHYSFS_tell(handle);
        if ( /* seeking within the already-buffered range? */
            ((offset >= 0) && (offset <= fh->buffill - fh->bufpos)) /* fwd */
            || ((offset < 0) && (-offset <= fh->bufpos)) /* backward */ )
        {
            fh->bufpos += (PHYSFS_uint32) offset;
            return 1; /* successful seek */
        } /* if */
    } /* if */

    /* we have to fall back to a 'raw' seek. */
    fh->buffill = fh->bufpos = 0;
    return fh->io->seek(fh->io, pos);
} /* PHYSFS_seek */


PHYSFS_sint64 PHYSFS_fileLength(PHYSFS_File *handle)
{
    PHYSFS_Io *io = ((FileHandle *) handle)->io;
    return io->length(io);
} /* PHYSFS_filelength */


int PHYSFS_setBuffer(PHYSFS_File *handle, PHYSFS_uint64 _bufsize)
{
    FileHandle *fh = (FileHandle *) handle;
    PHYSFS_uint32 bufsize;

    /* !!! FIXME: actually, why use 32 bits here? */
    /*BAIL_IF_MACRO(_bufsize > 0xFFFFFFFF, "buffer must fit in 32-bits", 0);*/
    BAIL_IF_MACRO(_bufsize > 0xFFFFFFFF, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    bufsize = (PHYSFS_uint32) _bufsize;

    BAIL_IF_MACRO(!PHYSFS_flush(handle), ERRPASS, 0);

    /*
     * For reads, we need to move the file pointer to where it would be
     *  if we weren't buffering, so that the next read will get the
     *  right chunk of stuff from the file. PHYSFS_flush() handles writes.
     */
    if ((fh->forReading) && (fh->buffill != fh->bufpos))
    {
        PHYSFS_uint64 pos;
        const PHYSFS_sint64 curpos = fh->io->tell(fh->io);
        BAIL_IF_MACRO(curpos == -1, ERRPASS, 0);
        pos = ((curpos - fh->buffill) + fh->bufpos);
        BAIL_IF_MACRO(!fh->io->seek(fh->io, pos), ERRPASS, 0);
    } /* if */

    if (bufsize == 0)  /* delete existing buffer. */
    {
        if (fh->buffer)
        {
            allocator.Free(fh->buffer);
            fh->buffer = NULL;
        } /* if */
    } /* if */

    else
    {
        PHYSFS_uint8 *newbuf;
        newbuf = (PHYSFS_uint8 *) allocator.Realloc(fh->buffer, bufsize);
        BAIL_IF_MACRO(!newbuf, PHYSFS_ERR_OUT_OF_MEMORY, 0);
        fh->buffer = newbuf;
    } /* else */

    fh->bufsize = bufsize;
    fh->buffill = fh->bufpos = 0;
    return 1;
} /* PHYSFS_setBuffer */


int PHYSFS_flush(PHYSFS_File *handle)
{
    FileHandle *fh = (FileHandle *) handle;
    PHYSFS_Io *io;
    PHYSFS_sint64 rc;

    if ((fh->forReading) || (fh->bufpos == fh->buffill))
        return 1;  /* open for read or buffer empty are successful no-ops. */

    /* dump buffer to disk. */
    io = fh->io;
    rc = io->write(io, fh->buffer + fh->bufpos, fh->buffill - fh->bufpos);
    BAIL_IF_MACRO(rc <= 0, ERRPASS, 0);
    fh->bufpos = fh->buffill = 0;
    return io->flush ? io->flush(io) : 1;
} /* PHYSFS_flush */


int PHYSFS_stat(const char *_fname, PHYSFS_Stat *stat)
{
    int retval = 0;
    char *fname;
    size_t len;

    BAIL_IF_MACRO(!_fname, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    BAIL_IF_MACRO(!stat, PHYSFS_ERR_INVALID_ARGUMENT, 0);
    len = strlen(_fname) + 1;
    fname = (char *) __PHYSFS_smallAlloc(len);
    BAIL_IF_MACRO(!fname, PHYSFS_ERR_OUT_OF_MEMORY, 0);

    /* set some sane defaults... */
    stat->filesize = -1;
    stat->modtime = -1;
    stat->createtime = -1;
    stat->accesstime = -1;
    stat->filetype = PHYSFS_FILETYPE_OTHER;
    stat->readonly = 1;  /* !!! FIXME */

    if (sanitizePlatformIndependentPath(_fname, fname))
    {
        if (*fname == '\0')
        {
            stat->filetype = PHYSFS_FILETYPE_DIRECTORY;
            stat->readonly = !writeDir; /* Writeable if we have a writeDir */
            retval = 1;
        } /* if */
        else
        {
            DirHandle *i;
            int exists = 0;
            __PHYSFS_platformGrabMutex(stateLock);
            for (i = searchPath; ((i != NULL) && (!exists)); i = i->next)
            {
                char *arcfname = fname;
                exists = partOfMountPoint(i, arcfname);
                if (exists)
                {
                    stat->filetype = PHYSFS_FILETYPE_DIRECTORY;
                    stat->readonly = 1;  /* !!! FIXME */
                    retval = 1;
                } /* if */
                else if (verifyPath(i, &arcfname, 0))
                {
                    /* !!! FIXME: this test is wrong and should be elsewhere. */
                    stat->readonly = !(writeDir &&
                                 (strcmp(writeDir->dirName, i->dirName) == 0));
                    retval = i->funcs->stat(i->opaque, arcfname, stat);
                    if ((retval) || (currentErrorCode() != PHYSFS_ERR_NOT_FOUND))
                        exists = 1;
                } /* else if */
            } /* for */
            __PHYSFS_platformReleaseMutex(stateLock);
        } /* else */
    } /* if */

    __PHYSFS_smallFree(fname);
    return retval;
} /* PHYSFS_stat */


int __PHYSFS_readAll(PHYSFS_Io *io, void *buf, const PHYSFS_uint64 len)
{
    return (io->read(io, buf, len) == len);
} /* __PHYSFS_readAll */


void *__PHYSFS_initSmallAlloc(void *ptr, PHYSFS_uint64 len)
{
    void *useHeap = ((ptr == NULL) ? ((void *) 1) : ((void *) 0));
    if (useHeap)  /* too large for stack allocation or alloca() failed. */
        ptr = allocator.Malloc(len+sizeof (void *));

    if (ptr != NULL)
    {
        void **retval = (void **) ptr;
        /*printf("%s alloc'd (%d) bytes at (%p).\n",
                useHeap ? "heap" : "stack", (int) len, ptr);*/
        *retval = useHeap;
        return retval + 1;
    } /* if */

    return NULL;  /* allocation failed. */
} /* __PHYSFS_initSmallAlloc */


void __PHYSFS_smallFree(void *ptr)
{
    if (ptr != NULL)
    {
        void **block = ((void **) ptr) - 1;
        const int useHeap = (*block != 0);
        if (useHeap)
            allocator.Free(block);
        /*printf("%s free'd (%p).\n", useHeap ? "heap" : "stack", block);*/
    } /* if */
} /* __PHYSFS_smallFree */


int PHYSFS_setAllocator(const PHYSFS_Allocator *a)
{
    BAIL_IF_MACRO(initialized, PHYSFS_ERR_IS_INITIALIZED, 0);
    externalAllocator = (a != NULL);
    if (externalAllocator)
        memcpy(&allocator, a, sizeof (PHYSFS_Allocator));

    return 1;
} /* PHYSFS_setAllocator */


const PHYSFS_Allocator *PHYSFS_getAllocator(void)
{
    BAIL_IF_MACRO(!initialized, PHYSFS_ERR_NOT_INITIALIZED, NULL);
    return &allocator;
} /* PHYSFS_getAllocator */


static void *mallocAllocatorMalloc(PHYSFS_uint64 s)
{
    if (!__PHYSFS_ui64FitsAddressSpace(s))
        BAIL_MACRO(PHYSFS_ERR_OUT_OF_MEMORY, NULL);
    #undef malloc
    return malloc((size_t) s);
} /* mallocAllocatorMalloc */


static void *mallocAllocatorRealloc(void *ptr, PHYSFS_uint64 s)
{
    if (!__PHYSFS_ui64FitsAddressSpace(s))
        BAIL_MACRO(PHYSFS_ERR_OUT_OF_MEMORY, NULL);
    #undef realloc
    return realloc(ptr, (size_t) s);
} /* mallocAllocatorRealloc */


static void mallocAllocatorFree(void *ptr)
{
    #undef free
    free(ptr);
} /* mallocAllocatorFree */


static void setDefaultAllocator(void)
{
    assert(!externalAllocator);
    if (!__PHYSFS_platformSetDefaultAllocator(&allocator))
    {
        allocator.Init = NULL;
        allocator.Deinit = NULL;
        allocator.Malloc = mallocAllocatorMalloc;
        allocator.Realloc = mallocAllocatorRealloc;
        allocator.Free = mallocAllocatorFree;
    } /* if */
} /* setDefaultAllocator */

/* end of physfs.c ... */