/** @file
 * File utility definitions
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#ifndef __FILE_UTIL_H__
#define __FILE_UTIL_H__

#include <stdbool.h>

#include "ws_symbol_export.h"

#ifdef _WIN32
#include <io.h>		/* for _read(), _write(), etc. */
#include <gmodule.h>
#endif

#include <fcntl.h>	/* for open() */

#ifdef HAVE_UNISTD_H
#include <unistd.h>	/* for read(), write(), close(), etc. */
#endif

#include <sys/stat.h>	/* for stat() and struct stat */

#include <stdio.h>

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

/* We set a larger IO Buffer size for the capture files */
#define IO_BUF_SIZE (64 * 1024)

/*
 * Visual C++ on Win32 systems doesn't define these.  (Old UNIX systems don't
 * define them either.)
 *
 * Visual C++ on Win32 systems doesn't define S_IFIFO, it defines _S_IFIFO.
 */
#ifndef S_ISREG
#define S_ISREG(mode)   (((mode) & S_IFMT) == S_IFREG)
#endif
#ifndef S_IFIFO
#define S_IFIFO _S_IFIFO
#endif
#ifndef S_ISFIFO
#define S_ISFIFO(mode)  (((mode) & S_IFMT) == S_IFIFO)
#endif
#ifndef S_ISDIR
#define S_ISDIR(mode)   (((mode) & S_IFMT) == S_IFDIR)
#endif

#ifdef _WIN32

/*
 * The structure to pass to ws_stat64() and ws_fstat64().
 */
#define ws_statb64	struct _stat64

/*  Win32 (and Win64): we use UTF-8 for filenames and pathnames throughout
 *  the code, so file functions must convert filenames and pathnames from
 *  UTF-8 to UTF-16 as we use NT Unicode (Win9x - now unsupported - used
 *  locale-based encoding here).  Microsoft's UN*X-style wrappers don't
 *  do that - they expect locale-based encodings - so we need our own
 *  wrappers.  (We don't use the wrappers from GLib as that would, at
 *  least for the wrappers that return file descriptors or take them
 *  as arguments, require that we use the version of the C runtime with
 *  which the GLib binaries were built, and we can't guarantee to do that.)
 *
 *  Note also that ws_stdio_rename() uses MoveFileEx() with
 *  MOVEFILE_REPLACE_EXISTING, so that it acts like UN*X rename(),
 *  removing the target if necessary.
 */

WS_DLL_PUBLIC int ws_stdio_open (const char *filename, int flags, int mode);
WS_DLL_PUBLIC int ws_stdio_rename (const char *oldfilename, const char *newfilename);
WS_DLL_PUBLIC int ws_stdio_mkdir (const char *filename, int mode);
WS_DLL_PUBLIC int ws_stdio_stat64 (const char *filename, ws_statb64 *buf);
WS_DLL_PUBLIC int ws_stdio_unlink (const char *filename);
WS_DLL_PUBLIC int ws_stdio_remove (const char *filename);

WS_DLL_PUBLIC FILE * ws_stdio_fopen (const char *filename, const char *mode);
WS_DLL_PUBLIC FILE * ws_stdio_freopen (const char *filename, const char *mode, FILE *stream);

#define ws_open		ws_stdio_open
#define ws_rename	ws_stdio_rename
#define ws_mkdir	ws_stdio_mkdir
#define ws_stat64	ws_stdio_stat64
#define ws_unlink	ws_stdio_unlink
#define ws_remove	ws_stdio_remove
#define ws_fopen	ws_stdio_fopen
#define ws_freopen	ws_stdio_freopen

/*
 * These routines don't take pathnames, so they don't require
 * pathname-converting wrappers on Windows.
 */

typedef unsigned int ws_file_size_t;
typedef signed int ws_file_ssize_t;

#define ws_read    _read
#define ws_write   _write
#define ws_close   _close
#define ws_dup     _dup
#define ws_fseek64 _fseeki64	/* use _fseeki64 for 64-bit offset support */
#define ws_fstat64 _fstati64	/* use _fstati64 for 64-bit size support */
#define ws_ftell64 _ftelli64	/* use _ftelli64 for 64-bit offset support */
#define ws_lseek64 _lseeki64	/* use _lseeki64 for 64-bit offset support */
#define ws_fdopen  _fdopen
#define ws_fileno  _fileno
#define ws_isatty  _isatty
#define ws_getc_unlocked _fgetc_nolock

/*
 * Other CRT functions. getpid probably belongs in sys_util.h or proc_util.h
 * but neither yet exist.
 */
#define ws_getpid  _getpid
#define ws_umask  _umask

/* DLL loading */

/** Try to remove the current directory from the DLL search path.
 * SetDllDirectory is tried, then SetCurrentDirectory(program_dir)
 *
 * @return true if we were able to call SetDllDirectory, false otherwise.
 */
WS_DLL_PUBLIC
bool ws_init_dll_search_path(void);

/** Load a DLL using LoadLibrary.
 * Only the system and program directories are searched.
 *
 * @param library_name The name of the DLL.
 * @return A handle to the DLL if found, NULL on failure.
 */

WS_DLL_PUBLIC
void *ws_load_library(const char *library_name);

/** Load wpcap.dll using g_module_open.
 * Only the system and program directories are searched.
 *
 * @return A handle to the DLL if found, NULL on failure.
 */
WS_DLL_PUBLIC
GModule *load_wpcap_module(void);

/** Create or open a "Wireshark is running" mutex.
 * Create or open a mutex which signals that Wireshark or its associated
 * executables is running. Used by the installer to test for a running application.
 */
WS_DLL_PUBLIC void create_app_running_mutex(void);

/** Close our "Wireshark is running" mutex.
 */
WS_DLL_PUBLIC void close_app_running_mutex(void);

/** Close a file descriptor if it is not open
 */
WS_DLL_PUBLIC int ws_close_if_possible(int fd);

#else	/* _WIN32 */

/*
 * The structure to pass to ws_fstat64().
 */
#define ws_statb64	struct stat

/* Not Windows, presumed to be UN*X-compatible */
#define ws_open			open
#define ws_rename		rename
#define ws_mkdir(dir,mode)	mkdir(dir,mode)
#define ws_stat64		stat
#define ws_unlink		unlink
#define ws_remove		remove
#define ws_fopen		fopen
#define ws_freopen		freopen

typedef size_t ws_file_size_t;
typedef ssize_t ws_file_ssize_t;

#define ws_read    read
#define ws_write   write
#ifdef __cplusplus
/*
 * Just in case this is used in a class with a close method or member.
 */
#define ws_close   ::close
#else
#define ws_close   close
#endif

#define ws_close_if_possible ws_close

#define ws_dup     dup
#ifdef HAVE_FSEEKO
#define ws_fseek64 fseeko	/* AC_SYS_LARGEFILE should make off_t 64-bit */
#define ws_ftell64 ftello	/* AC_SYS_LARGEFILE should make off_t 64-bit */
#else
#define ws_fseek64(fh,offset,whence)	fseek(fh,(long)(offset),whence)
#define ws_ftell64 ftell
#endif
#define ws_fstat64 fstat	/* AC_SYS_LARGEFILE should make off_t 64-bit */
#define ws_lseek64 lseek	/* AC_SYS_LARGEFILE should make off_t 64-bit */
#define ws_fdopen  fdopen
#define ws_fileno  fileno
#define ws_isatty  isatty
#define ws_getc_unlocked getc_unlocked
#define O_BINARY   0		/* Win32 needs the O_BINARY flag for open() */

/* Other CRT functions */
#define ws_getpid  getpid
#define ws_umask   umask

#endif /* _WIN32 */

/* directory handling */
#define WS_DIR				GDir
#define WS_DIRENT			const char
#define ws_dir_open			g_dir_open
#define ws_dir_read_name		g_dir_read_name
#define ws_dir_get_name(dirent)		dirent
#define ws_dir_rewind			g_dir_rewind
#define ws_dir_close			g_dir_close

/* XXX - remove include "sys/stat.h" from files that include this header */
/* XXX - update docs (e.g. README.developer) */

/* Error codes from file handling routines */
#define FILE_ERR_CANT_OPEN        -1
#define FILE_ERR_CANT_COMPRESS    -2
#define FILE_ERR_SHORT_WRITE      -3
#define FILE_ERR_CANT_CLOSE       -4
#define FILE_ERR_INTERNAL         -5

#ifdef __cplusplus
}
#endif /* __cplusplus */

#endif /* __FILE_UTIL_H__ */
