/* mz_strm_posix.c -- Stream for filesystem access for posix/linux

   part of the minizip-ng project

   Copyright (C) Nathan Moinvaziri

     https://github.com/zlib-ng/minizip-ng

   Modifications for Zip64 support

     Copyright (C) 2009-2010 Mathias Svensson

     http://result42.com

   Copyright (C) 1998-2010 Gilles Vollant

     https://www.winimage.com/zLibDll/minizip.html

   This program is distributed under the terms of the same license as zlib.

   See the accompanying LICENSE file for the full text of the license.

*/

#include "mz.h"

#include "mz_strm.h"

#include "mz_strm_os.h"

#include <stdio.h> /* fopen, fread.. */

#include <errno.h>

#include <unistd.h>  // open, close, ...

#include <fcntl.h>   // O_NOFOLLOW, ...

/***************************************************************************/

#define fopen64 fopen

#ifndef MZ_FILE32_API

#  ifndef NO_FSEEKO

#    define ftello64 ftello

#    define fseeko64 fseeko

#  elif defined(_MSC_VER) && (_MSC_VER >= 1400)

#    define ftello64 _ftelli64

#    define fseeko64 _fseeki64

#  endif

#endif

#ifndef ftello64

#  define ftello64 ftell

#endif

#ifndef fseeko64

#  define fseeko64 fseek

#endif

/***************************************************************************/

static mz_stream_vtbl mz_stream_os_vtbl = {mz_stream_os_open,

                                           mz_stream_os_is_open,

                                           mz_stream_os_read,

                                           mz_stream_os_write,

                                           mz_stream_os_tell,

                                           mz_stream_os_seek,

                                           mz_stream_os_close,

                                           mz_stream_os_error,

                                           mz_stream_os_create,

                                           mz_stream_os_delete,

                                           NULL,

                                           NULL};

/***************************************************************************/

typedef struct mz_stream_posix_s {

    mz_stream stream;

    int32_t error;

    FILE *handle;

} mz_stream_posix;

/***************************************************************************/

int32_t mz_stream_os_open(void *stream, const char *path, int32_t mode) {

    mz_stream_posix *posix = (mz_stream_posix *)stream;

    const char *mode_fopen = NULL;

    int mode_open = 0;

    int fd;

    if (!path)

        return MZ_PARAM_ERROR;

    if ((mode & MZ_OPEN_MODE_READWRITE) == MZ_OPEN_MODE_READ) {

        mode_fopen = "r";

        mode_open = O_RDONLY;

    } else if (mode & MZ_OPEN_MODE_APPEND) {

        mode_fopen = "r+";

        mode_open = O_RDWR;

    } else if (mode & MZ_OPEN_MODE_CREATE) {

        mode_fopen = "w";

        mode_open = O_WRONLY | O_CREAT | O_TRUNC;

    } else

        return MZ_OPEN_ERROR;

    if (mode & MZ_OPEN_MODE_NOFOLLOW)

        mode_open |= O_NOFOLLOW;

    fd = open(path, mode_open, S_IRUSR | S_IWUSR | S_IRGRP);

    if (fd != -1) {

        posix->handle = fdopen(fd, mode_fopen);

        if (!posix->handle)

            close(fd);

    }

    if (!posix->handle) {

        posix->error = errno;

        return MZ_OPEN_ERROR;

    }

    if (mode & MZ_OPEN_MODE_APPEND)

        return mz_stream_os_seek(stream, 0, MZ_SEEK_END);

    return MZ_OK;

}

int32_t mz_stream_os_is_open(void *stream) {

    mz_stream_posix *posix = (mz_stream_posix *)stream;

    if (!posix->handle)

        return MZ_OPEN_ERROR;

    return MZ_OK;

}

int32_t mz_stream_os_read(void *stream, void *buf, int32_t size) {

    mz_stream_posix *posix = (mz_stream_posix *)stream;

    int32_t read = (int32_t)fread(buf, 1, (size_t)size, posix->handle);

    if (read < size && ferror(posix->handle)) {

        posix->error = errno;

        return MZ_READ_ERROR;

    }

    return read;

}

int32_t mz_stream_os_write(void *stream, const void *buf, int32_t size) {

    mz_stream_posix *posix = (mz_stream_posix *)stream;

    int32_t written = (int32_t)fwrite(buf, 1, (size_t)size, posix->handle);

    if (written < size && ferror(posix->handle)) {

        posix->error = errno;

        return MZ_WRITE_ERROR;

    }

    return written;

}

int64_t mz_stream_os_tell(void *stream) {

    mz_stream_posix *posix = (mz_stream_posix *)stream;

    int64_t position = ftello64(posix->handle);

    if (position == -1) {

        posix->error = errno;

        return MZ_TELL_ERROR;

    }

    return position;

}

int32_t mz_stream_os_seek(void *stream, int64_t offset, int32_t origin) {

    mz_stream_posix *posix = (mz_stream_posix *)stream;

    int32_t fseek_origin = 0;

    switch (origin) {

    case MZ_SEEK_CUR:

        fseek_origin = SEEK_CUR;

        break;

    case MZ_SEEK_END:

        fseek_origin = SEEK_END;

        break;

    case MZ_SEEK_SET:

        fseek_origin = SEEK_SET;

        break;

    default:

        return MZ_SEEK_ERROR;

    }

    if (fseeko64(posix->handle, offset, fseek_origin) != 0) {

        posix->error = errno;

        return MZ_SEEK_ERROR;

    }

    return MZ_OK;

}

int32_t mz_stream_os_close(void *stream) {

    mz_stream_posix *posix = (mz_stream_posix *)stream;

    int32_t closed = 0;

    if (posix->handle) {

        closed = fclose(posix->handle);

        posix->handle = NULL;

    }

    if (closed != 0) {

        posix->error = errno;

        return MZ_CLOSE_ERROR;

    }

    return MZ_OK;

}

int32_t mz_stream_os_error(void *stream) {

    mz_stream_posix *posix = (mz_stream_posix *)stream;

    return posix->error;

}

void *mz_stream_os_create(void) {

    mz_stream_posix *posix = (mz_stream_posix *)calloc(1, sizeof(mz_stream_posix));

    if (posix)

        posix->stream.vtbl = &mz_stream_os_vtbl;

    return posix;

}

void mz_stream_os_delete(void **stream) {

    mz_stream_posix *posix = NULL;

    if (!stream)

        return;

    posix = (mz_stream_posix *)*stream;

    free(posix);

    *stream = NULL;

}

void *mz_stream_os_get_interface(void) {

    return (void *)&mz_stream_os_vtbl;

}