file_util.h

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#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>
#include <glib/gstdio.h>    /* for g_open(), g_fopen(), etc. */
#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 enforce code page 65001 (UTF-8) as the active code page
 *  via an application manifest in our executables now, but someone could
 *  build a different application without a manifest and link against these
 *  libraries. (If we don't think that's a real problem, we could just map
 *  to the UCRT wrappers directly instead of the GLib wrappers.)
 *
 *  File descriptors and FILE pointers belong to the C runtime that
 *  created them, so callers of the wrappers that return or take them
 *  must use the same C runtime as GLib. Our builds use the same
 *  one for libwsutil and GLib (the UCRT, or the debug UCRT in Debug
 *  builds), and we already pass file descriptors to GLib, e.g. with
 *  g_io_channel_win32_new_fd(). With CMake, a plugin that uses the
 *  imported targets and the default MSVC_RUNTIME_LIBRARY gets the
 *  matching C runtime; one built with the static C runtime (/MT) or
 *  against MINGW64's msvcrt.dll doesn't.
 *
 *  We have our own ws_stdio_stat64() instead of g_stat(), which can't
 *  return the size of a file of 2 GB or more: with MSVC on 64-bit
 *  Windows, GStatBuf is struct stat, which has a 32-bit st_size.
 *
 *  Note also that g_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_stat64 (const char *filename, ws_statb64 *buf);
 
#define ws_open     g_open
#define ws_rename   g_rename
#define ws_mkdir    g_mkdir
#define ws_stat64   ws_stdio_stat64
#define ws_unlink   g_unlink
#define ws_remove   g_remove
#define ws_fopen    g_fopen
#define ws_freopen  g_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 */

WS_DLL_PUBLIC
bool ws_init_dll_search_path(void);

 
WS_DLL_PUBLIC
void *ws_load_library(const char *library_name);

WS_DLL_PUBLIC
GModule *load_wpcap_module(void);

WS_DLL_PUBLIC void create_app_running_mutex(void);

WS_DLL_PUBLIC void close_app_running_mutex(void);

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__ */