open_toontown_panda3d/dtool/src/dtoolutil/filename.cxx

3096 lines
87 KiB
C++

/**
* PANDA 3D SOFTWARE
* Copyright (c) Carnegie Mellon University. All rights reserved.
*
* All use of this software is subject to the terms of the revised BSD
* license. You should have received a copy of this license along
* with this source code in a file named "LICENSE."
*
* @file filename.cxx
* @author drose
* @date 1999-01-18
*/
#include "filename.h"
#include "filename_assist.h"
#include "dSearchPath.h"
#include "executionEnvironment.h"
#include "vector_string.h"
#include "atomicAdjust.h"
#include <stdio.h> // For rename() and tempnam()
#include <time.h> // for clock() and time()
#include <sys/stat.h>
#include <algorithm>
#ifdef PHAVE_UTIME_H
#include <utime.h>
// We assume we have these too.
#include <errno.h>
#include <fcntl.h>
#endif
#ifdef PHAVE_GLOB_H
#include <glob.h>
#ifndef GLOB_NOMATCH
#define GLOB_NOMATCH -3
#endif
#endif
#ifdef PHAVE_DIRENT_H
#include <dirent.h>
#endif
// It's true that dtoolbase.h includes this already, but we include this again
// in case we are building this file within ppremake.
#ifdef PHAVE_UNISTD_H
#include <unistd.h>
#endif
#if defined(__ANDROID__) && !defined(PHAVE_LOCKF)
// Needed for flock.
#include <sys/file.h>
#endif
using std::cerr;
using std::ios;
using std::string;
using std::wstring;
TextEncoder::Encoding Filename::_filesystem_encoding = TextEncoder::E_utf8;
TVOLATILE AtomicAdjust::Pointer Filename::_home_directory;
TVOLATILE AtomicAdjust::Pointer Filename::_temp_directory;
TVOLATILE AtomicAdjust::Pointer Filename::_user_appdata_directory;
TVOLATILE AtomicAdjust::Pointer Filename::_common_appdata_directory;
TypeHandle Filename::_type_handle;
#ifdef ANDROID
string Filename::_internal_data_dir;
#endif
#ifdef WIN32
/* begin Win32-specific code */
#ifdef WIN32_VC
#include <direct.h>
#include <windows.h>
#include <shlobj.h>
#include <io.h>
#endif
// The MSVC 6.0 Win32 SDK lacks the following definitions, so we define them
// here for compatibility.
#ifndef FILE_ATTRIBUTE_DEVICE
#define FILE_ATTRIBUTE_DEVICE 0x00000040
#endif
// We might have been linked with the Cygwin dll. This is ideal if it is
// available, because it allows Panda to access all the Cygwin mount
// definitions if they are in use. If the Cygwin dll is not available, we
// fall back to our own convention for converting pathnames.
#ifdef HAVE_CYGWIN
extern "C" void cygwin_conv_to_win32_path(const char *path, char *win32);
extern "C" void cygwin_conv_to_posix_path(const char *path, char *posix);
#endif
/*
* Windows uses the convention \\hostname\path\to\file to represent a pathname
* to a file on another share. This redefines a pathname to be something more
* complicated than a sequence of directory names separated by slashes. The
* Unix convention to represent the same thing is, like everything else, to
* graft the reference to the remote hostname into the one global filesystem,
* with something like hostshostnamepathtofile. We observe the Unix
* convention for internal names used in Panda; this makes operations like
* Filename::get_dirname() simpler and more internally consistent.
*/
/*
* This string hard-defines the prefix that we use internally to indicate that
* the next directory component name should be treated as a hostname. It
* might be nice to use a ConfigVariable for this, except that we haven't
* defined ConfigVariable by this point (and indeed we can't, since we need to
* have a Filename class already created in order to read the first config
* file). Windows purists might be tempted to define this to a double slash
* so that internal Panda filenames more closely resemble their Windows
* counterparts. That might actually work, but it will cause problems with
* Filename::standardize().
*/
// We use const char * instead of string to avoid static-init ordering issues.
static const char *hosts_prefix = "/hosts/";
static size_t hosts_prefix_length = 7;
static string
front_to_back_slash(const string &str) {
string result = str;
string::iterator si;
for (si = result.begin(); si != result.end(); ++si) {
if ((*si) == '/') {
(*si) = '\\';
}
}
return result;
}
static string
back_to_front_slash(const string &str) {
string result = str;
string::iterator si;
for (si = result.begin(); si != result.end(); ++si) {
if ((*si) == '\\') {
(*si) = '/';
}
}
return result;
}
static const string &
get_panda_root() {
static string *panda_root = nullptr;
if (panda_root == nullptr) {
panda_root = new string;
const char *envvar = getenv("PANDA_ROOT");
if (envvar != nullptr) {
(*panda_root) = front_to_back_slash(envvar);
}
// Ensure the string ends in a backslash. If PANDA_ROOT is empty or
// undefined, this function must return a single backslash--not an empty
// string--since this prefix is used to replace a leading slash in
// Filename::to_os_specific().
if ((*panda_root).empty() || (*panda_root)[(*panda_root).length() - 1] != '\\') {
(*panda_root) += '\\';
}
}
return (*panda_root);
}
static string
convert_pathname(const string &unix_style_pathname) {
if (unix_style_pathname.empty()) {
return string();
}
// To convert from a Unix-style pathname to a Windows-style pathname, we
// need to change all forward slashes to backslashes. We might need to add
// a prefix as well, since Windows pathnames typically begin with a drive
// letter.
// By convention, if the top directory name consists of just one letter, we
// treat that as a drive letter and map the rest of the filename
// accordingly. On the other hand, if the top directory name consists of
// more than one letter, we assume this is a file within some predefined
// tree whose root is given by the environment variable "PANDA_ROOT", or if
// that is not defined, "CYGWIN_ROOT" (for backward compatibility).
string windows_pathname;
if (unix_style_pathname[0] != '/') {
// It doesn't even start from the root, so we don't have to do anything
// fancy--relative pathnames are the same in Windows as in Unix, except
// for the direction of the slashes.
windows_pathname = front_to_back_slash(unix_style_pathname);
} else if (unix_style_pathname.length() >= 2 &&
isalpha(unix_style_pathname[1]) &&
(unix_style_pathname.length() == 2 || unix_style_pathname[2] == '/')) {
// This pathname begins with a slash and a single letter. That must be
// the drive letter.
string remainder = unix_style_pathname.substr(2);
if (remainder.empty()) {
// There's a difference between "C:" and "C:".
remainder = "/";
}
remainder = front_to_back_slash(remainder);
// We have to cast the result of toupper() to (char) to help some
// compilers (e.g. Cygwin's gcc 2.95.3) happy; so that they do not
// confuse this string constructor with one that takes two iterators.
windows_pathname =
string(1, (char)toupper(unix_style_pathname[1])) + ":" + remainder;
} else if (unix_style_pathname.length() > hosts_prefix_length &&
unix_style_pathname.substr(0, hosts_prefix_length) == hosts_prefix) {
// A filename like hostsfooby gets turned into \\fooby.
windows_pathname = "\\\\" + front_to_back_slash(unix_style_pathname.substr(hosts_prefix_length));
} else {
// It starts with a slash, but the first part is not a single letter.
#ifdef HAVE_CYGWIN
// Use Cygwin to convert it if possible.
char result[4096] = "";
cygwin_conv_to_win32_path(unix_style_pathname.c_str(), result);
windows_pathname = result;
#else // HAVE_CYGWIN
// Without Cygwin, just prefix $PANDA_ROOT.
windows_pathname = get_panda_root();
windows_pathname += front_to_back_slash(unix_style_pathname.substr(1));
#endif // HAVE_CYGWIN
}
return windows_pathname;
}
static string
convert_dso_pathname(const string &unix_style_pathname) {
// If the extension is .so, change it to .dll.
size_t dot = unix_style_pathname.rfind('.');
if (dot == string::npos ||
unix_style_pathname.find('/', dot) != string::npos) {
// No filename extension.
return convert_pathname(unix_style_pathname);
}
if (unix_style_pathname.substr(dot) != ".so") {
// Some other extension.
return convert_pathname(unix_style_pathname);
}
string dll_basename = unix_style_pathname.substr(0, dot);
#ifdef _DEBUG
// If we're building a debug version, all the dso files we link in must be
// named file_d.dll. This does prohibit us from linking in external dso
// files, generated outside of the Panda build system, that don't follow
// this _d convention. Maybe we need a separate
// convert_system_dso_pathname() function.
// We can't simply check to see if the file exists, because this might not
// be a full path to the dso filename--it might be somewhere on the
// LD_LIBRARY_PATH, or on PATH, or any of a number of nutty places.
return convert_pathname(dll_basename + "_d.dll");
#else
return convert_pathname(dll_basename + ".dll");
#endif
}
static string
convert_executable_pathname(const string &unix_style_pathname) {
// If the extension is not .exe, append .exe.
size_t dot = unix_style_pathname.rfind('.');
if (dot == string::npos ||
unix_style_pathname.find('/', dot) != string::npos) {
// No filename extension.
return convert_pathname(unix_style_pathname + ".exe");
}
if (unix_style_pathname.substr(dot) != ".exe") {
// Some other extension.
return convert_pathname(unix_style_pathname + ".exe");
}
return convert_pathname(unix_style_pathname);
}
#endif //WIN32
/**
* This constructor composes the filename out of a directory part and a
* basename part. It will insert an intervening '/' if necessary.
*/
Filename::
Filename(const Filename &dirname, const Filename &basename) {
if (dirname.empty()) {
(*this) = basename;
} else {
_flags = basename._flags;
string dirpath = dirname.get_fullpath();
if (dirpath[dirpath.length() - 1] == '/') {
(*this) = dirpath + basename.get_fullpath();
} else {
(*this) = dirpath + "/" + basename.get_fullpath();
}
}
}
/**
* This named constructor returns a Panda-style filename (that is, using
* forward slashes, and no drive letter) based on the supplied filename string
* that describes a filename in the local system conventions (for instance, on
* Windows, it may use backslashes or begin with a drive letter and a colon).
*
* Use this function to create a Filename from an externally-given filename
* string. Use to_os_specific() again later to reconvert it back to the local
* operating system's conventions.
*
* This function will do the right thing even if the filename is partially
* local conventions and partially Panda conventions; e.g. some backslashes
* and some forward slashes.
*/
Filename Filename::
from_os_specific(const string &os_specific, Filename::Type type) {
#ifdef WIN32
string result = back_to_front_slash(os_specific);
const string &panda_root = get_panda_root();
// If the initial prefix is the same as panda_root, remove it.
if (!panda_root.empty() && panda_root != string("\\") &&
panda_root.length() < result.length()) {
bool matches = true;
size_t p;
for (p = 0; p < panda_root.length() && matches; ++p) {
char c = tolower(panda_root[p]);
if (c == '\\') {
c = '/';
}
matches = (c == tolower(result[p]));
}
if (matches) {
// The initial prefix matches! Replace the initial bit with a leading
// slash.
result = result.substr(panda_root.length());
assert(!result.empty());
if (result[0] != '/') {
result = '/' + result;
}
Filename filename(result);
filename.set_type(type);
return filename;
}
}
// All right, the initial prefix was not under panda_root. But maybe it
// begins with a drive letter.
if (result.size() >= 3 && isalpha(result[0]) &&
result[1] == ':' && result[2] == '/') {
result[1] = tolower(result[0]);
result[0] = '/';
// If there's *just* a slash following the drive letter, go ahead and trim
// it.
if (result.size() == 3) {
result = result.substr(0, 2);
}
} else if (result.substr(0, 2) == "//") {
// If the initial prefix is a double slash, convert it to hosts.
result = hosts_prefix + result.substr(2);
}
Filename filename(result);
filename.set_type(type);
return filename;
#else // WIN32
// Generic Unix-style filenames--no conversion necessary.
Filename filename(os_specific);
filename.set_type(type);
return filename;
#endif // WIN32
}
/**
* The wide-string variant of from_os_specific(). Returns a new Filename,
* converted from an os-specific wide-character string.
*/
Filename Filename::
from_os_specific_w(const wstring &os_specific, Filename::Type type) {
TextEncoder encoder;
encoder.set_encoding(get_filesystem_encoding());
encoder.set_wtext(os_specific);
return from_os_specific(encoder.get_text(), type);
}
/**
* Returns the same thing as from_os_specific(), but embedded environment
* variable references (e.g. "$DMODELS/foo.txt") are expanded out. It also
* automatically elevates the file to its true case if needed.
*/
Filename Filename::
expand_from(const string &os_specific, Filename::Type type) {
Filename file = from_os_specific(ExecutionEnvironment::expand_string(os_specific),
type);
file.make_true_case();
return file;
}
/**
* Generates a temporary filename within the indicated directory, using the
* indicated prefix. If the directory is empty, a system-defined directory is
* chosen instead.
*
* The generated filename did not exist when the Filename checked, but since
* it does not specifically create the file, it is possible that another
* process could simultaneously create a file by the same name.
*/
Filename Filename::
temporary(const string &dirname, const string &prefix, const string &suffix,
Type type) {
Filename fdirname = dirname;
#if defined(_WIN32) || defined(ANDROID)
// The Windows tempnam() function doesn't do a good job of choosing a
// temporary directory. Choose one ourselves.
if (fdirname.empty()) {
fdirname = Filename::get_temp_directory();
}
#endif
if (fdirname.empty()) {
// If we are not given a dirname, use the system tempnam() function to
// create a system-defined temporary filename.
char *name = tempnam(nullptr, prefix.c_str());
Filename result = Filename::from_os_specific(name);
free(name);
result.set_type(type);
return result;
}
// If we *are* given a dirname, then use our own algorithm to make up a
// filename within that dirname. We do that because the system tempnam()
// (for instance, under Windows) may ignore the dirname.
Filename result;
do {
// We take the time of day and multiply it by the process time. This will
// give us a very large number, of which we take the bottom 24 bits and
// generate a 6-character hex code.
int hash = (clock() * time(nullptr)) & 0xffffff;
char hex_code[10];
#ifdef _WIN32
sprintf_s(hex_code, 10, "%06x", hash);
#else
snprintf(hex_code, 10, "%06x", hash);
#endif
result = Filename(fdirname, Filename(prefix + hex_code + suffix));
result.set_type(type);
} while (result.exists());
return result;
}
/**
* Returns a path to the user's home directory, if such a thing makes sense in
* the current OS, or to the nearest equivalent. This may or may not be
* directly writable by the application.
*/
const Filename &Filename::
get_home_directory() {
if (AtomicAdjust::get_ptr(_home_directory) == nullptr) {
Filename home_directory;
// In all environments, check $HOME first.
char *home = getenv("HOME");
if (home != nullptr) {
Filename dirname = from_os_specific(home);
if (dirname.is_directory()) {
if (dirname.make_canonical()) {
home_directory = dirname;
}
}
}
if (home_directory.empty()) {
#ifdef WIN32
wchar_t buffer[MAX_PATH];
// On Windows, fall back to the "My Documents" folder.
if (SHGetSpecialFolderPathW(nullptr, buffer, CSIDL_PERSONAL, true)) {
Filename dirname = from_os_specific_w(buffer);
if (dirname.is_directory()) {
if (dirname.make_canonical()) {
home_directory = dirname;
}
}
}
#elif defined(ANDROID)
// Temporary hack.
home_directory = "/data/data/org.panda3d.sdk";
#elif defined(IS_OSX)
home_directory = get_osx_home_directory();
#elif defined(ANDROID)
home_directory = _internal_data_dir;
#else
// Posix case: check etcpasswd?
#endif // WIN32
}
if (home_directory.empty()) {
// Fallback case.
home_directory = ExecutionEnvironment::get_cwd();
}
Filename *newdir = new Filename(home_directory);
if (AtomicAdjust::compare_and_exchange_ptr(_home_directory, nullptr, newdir) != nullptr) {
// Didn't store it. Must have been stored by someone else.
assert(_home_directory != nullptr);
delete newdir;
}
}
return (*(Filename *)_home_directory);
}
/**
* Returns a path to a system-defined temporary directory.
*/
const Filename &Filename::
get_temp_directory() {
if (AtomicAdjust::get_ptr(_temp_directory) == nullptr) {
Filename temp_directory;
#ifdef WIN32
static const size_t buffer_size = 4096;
wchar_t buffer[buffer_size];
if (GetTempPathW(buffer_size, buffer) != 0) {
Filename dirname = from_os_specific_w(buffer);
if (dirname.is_directory()) {
if (dirname.make_canonical()) {
temp_directory = dirname;
}
}
}
#elif defined(IS_OSX)
temp_directory = get_osx_temp_directory();
#elif defined(ANDROID)
temp_directory.set_dirname(_internal_data_dir);
temp_directory.set_basename("cache");
#else
// Posix case.
temp_directory = "/tmp";
#endif // WIN32
if (temp_directory.empty()) {
// Fallback case.
temp_directory = ExecutionEnvironment::get_cwd();
}
Filename *newdir = new Filename(temp_directory);
if (AtomicAdjust::compare_and_exchange_ptr(_temp_directory, nullptr, newdir) != nullptr) {
// Didn't store it. Must have been stored by someone else.
assert(_temp_directory != nullptr);
delete newdir;
}
}
return (*(Filename *)_temp_directory);
}
/**
* Returns a path to a system-defined directory appropriate for creating a
* subdirectory for storing application-specific data, specific to the current
* user.
*/
const Filename &Filename::
get_user_appdata_directory() {
if (AtomicAdjust::get_ptr(_user_appdata_directory) == nullptr) {
Filename user_appdata_directory;
#ifdef WIN32
wchar_t buffer[MAX_PATH];
if (SHGetSpecialFolderPathW(nullptr, buffer, CSIDL_LOCAL_APPDATA, true)) {
Filename dirname = from_os_specific_w(buffer);
if (dirname.is_directory()) {
if (dirname.make_canonical()) {
user_appdata_directory = dirname;
}
}
}
#elif defined(IS_OSX)
user_appdata_directory = get_osx_user_appdata_directory();
#elif defined(ANDROID)
user_appdata_directory.set_dirname(_internal_data_dir);
user_appdata_directory.set_basename("files");
#else
// Posix case. We follow the XDG base directory spec.
struct stat st;
const char *datadir = getenv("XDG_DATA_HOME");
if (datadir != nullptr && stat(datadir, &st) == 0 && S_ISDIR(st.st_mode)) {
user_appdata_directory = datadir;
} else {
user_appdata_directory = Filename(get_home_directory(), ".local/share");
}
#endif // WIN32
if (user_appdata_directory.empty()) {
// Fallback case.
user_appdata_directory = ExecutionEnvironment::get_cwd();
}
Filename *newdir = new Filename(user_appdata_directory);
if (AtomicAdjust::compare_and_exchange_ptr(_user_appdata_directory, nullptr, newdir) != nullptr) {
// Didn't store it. Must have been stored by someone else.
assert(_user_appdata_directory != nullptr);
delete newdir;
}
}
return (*(Filename *)_user_appdata_directory);
}
/**
* Returns a path to a system-defined directory appropriate for creating a
* subdirectory for storing application-specific data, common to all users.
*/
const Filename &Filename::
get_common_appdata_directory() {
if (AtomicAdjust::get_ptr(_common_appdata_directory) == nullptr) {
Filename common_appdata_directory;
#ifdef WIN32
wchar_t buffer[MAX_PATH];
if (SHGetSpecialFolderPathW(nullptr, buffer, CSIDL_COMMON_APPDATA, true)) {
Filename dirname = from_os_specific_w(buffer);
if (dirname.is_directory()) {
if (dirname.make_canonical()) {
common_appdata_directory = dirname;
}
}
}
#elif defined(IS_OSX)
common_appdata_directory = get_osx_common_appdata_directory();
#elif defined(ANDROID)
common_appdata_directory.set_dirname(_internal_data_dir);
common_appdata_directory.set_basename("files");
#elif defined(__FreeBSD__)
common_appdata_directory = "/usr/local/share";
#else
common_appdata_directory = "/usr/share";
#endif // WIN32
if (common_appdata_directory.empty()) {
// Fallback case.
common_appdata_directory = ExecutionEnvironment::get_cwd();
}
Filename *newdir = new Filename(common_appdata_directory);
if (AtomicAdjust::compare_and_exchange_ptr(_common_appdata_directory, nullptr, newdir) != nullptr) {
// Didn't store it. Must have been stored by someone else.
assert(_common_appdata_directory != nullptr);
delete newdir;
}
}
return (*(Filename *)_common_appdata_directory);
}
/**
* Replaces the entire filename: directory, basename, extension. This can
* also be achieved with the assignment operator.
*/
void Filename::
set_fullpath(const string &s) {
(*this) = s;
}
/**
* Replaces the directory part of the filename. This is everything in the
* filename up to, but not including the rightmost slash.
*/
void Filename::
set_dirname(const string &s) {
if (s.empty()) {
// Remove the directory prefix altogether.
_filename.replace(0, _basename_start, "");
int length_change = - ((int)_basename_start);
_dirname_end = 0;
_basename_start += length_change;
_basename_end += length_change;
_extension_start += length_change;
} else {
// Replace the existing directory prefix, or insert a new one.
// We build the string ss to include the terminal slash.
string ss;
if (s[s.length()-1] == '/') {
ss = s;
} else {
ss = s+'/';
}
int length_change = (int)ss.length() - (int)_basename_start;
_filename.replace(0, _basename_start, ss);
_dirname_end = ss.length() - 1;
// An exception: if the dirname string was the single slash, the dirname
// includes that slash.
if (ss.length() == 1) {
_dirname_end = 1;
}
_basename_start += length_change;
if (_basename_end != string::npos) {
_basename_end += length_change;
_extension_start += length_change;
}
}
locate_hash();
}
/**
* Replaces the basename part of the filename. This is everything in the
* filename after the rightmost slash, including any extensions.
*/
void Filename::
set_basename(const string &s) {
_filename.replace(_basename_start, string::npos, s);
locate_extension();
locate_hash();
}
/**
* Replaces the full filename--directory and basename parts--except for the
* extension.
*/
void Filename::
set_fullpath_wo_extension(const string &s) {
int length_change = (int)s.length() - (int)_basename_end;
_filename.replace(0, _basename_end, s);
if (_basename_end != string::npos) {
_basename_end += length_change;
_extension_start += length_change;
}
locate_hash();
}
/**
* Replaces the basename part of the filename, without the file extension.
*/
void Filename::
set_basename_wo_extension(const string &s) {
int length_change = (int)s.length() - (int)(_basename_end - _basename_start);
if (_basename_end == string::npos) {
_filename.replace(_basename_start, string::npos, s);
} else {
_filename.replace(_basename_start, _basename_end - _basename_start, s);
_basename_end += length_change;
_extension_start += length_change;
}
locate_hash();
}
/**
* Replaces the file extension. This is everything after the rightmost dot,
* if there is one, or the empty string if there is not.
*/
void Filename::
set_extension(const string &s) {
if (s.empty()) {
// Remove the extension altogether.
if (_basename_end != string::npos) {
_filename.replace(_basename_end, string::npos, "");
_basename_end = string::npos;
_extension_start = string::npos;
}
} else if (_basename_end == string::npos) {
// Insert an extension where there was none before.
_basename_end = _filename.length();
_extension_start = _filename.length() + 1;
_filename += '.' + s;
} else {
// Replace an existing extension.
_filename.replace(_extension_start, string::npos, s);
}
locate_hash();
}
/**
* If the pattern flag is set for this Filename and the filename string
* actually includes a sequence of hash marks, then this returns a new
* Filename with the sequence of hash marks replaced by the indicated index
* number.
*
* If the pattern flag is not set for this Filename or it does not contain a
* sequence of hash marks, this quietly returns the original filename.
*/
Filename Filename::
get_filename_index(int index) const {
Filename file(*this);
if (_hash_end != _hash_start) {
std::ostringstream strm;
strm << _filename.substr(0, _hash_start)
<< std::setw((int)(_hash_end - _hash_start)) << std::setfill('0') << index
<< _filename.substr(_hash_end);
file.set_fullpath(strm.str());
}
file.set_pattern(false);
return file;
}
/**
* Replaces the part of the filename from the beginning of the hash sequence
* to the end of the filename.
*/
void Filename::
set_hash_to_end(const string &s) {
_filename.replace(_hash_start, string::npos, s);
locate_basename();
locate_extension();
locate_hash();
}
/**
* Extracts out the individual directory components of the path into a series
* of strings. get_basename() will be the last component stored in the
* vector. Note that no distinction is made by this method between a leading
* slash and no leading slash, but you can call is_local() to differentiate
* the two cases.
*/
void Filename::
extract_components(vector_string &components) const {
components.clear();
size_t p = 0;
if (!_filename.empty() && _filename[0] == '/') {
// Skip the leading slash.
p = 1;
}
while (p < _filename.length()) {
size_t q = _filename.find('/', p);
if (q == string::npos) {
components.push_back(_filename.substr(p));
return;
}
components.push_back(_filename.substr(p, q - p));
p = q + 1;
}
// A trailing slash means we have an empty get_basename().
components.push_back(string());
}
/**
* Converts the filename to standard form by replacing consecutive slashes
* with a single slash, removing a trailing slash if present, and backing up
* over .. sequences within the filename where possible.
*/
void Filename::
standardize() {
assert(!_filename.empty());
if (_filename == ".") {
// Don't change a single dot; this refers to the current directory.
return;
}
vector_string components;
// Pull off the components of the filename one at a time.
bool global = (_filename[0] == '/');
size_t p = 0;
while (p < _filename.length() && _filename[p] == '/') {
p++;
}
while (p < _filename.length()) {
size_t slash = _filename.find('/', p);
string component = _filename.substr(p, slash - p);
if (component == "." && p != 0) {
// Ignore ..
} else if (component == ".." && !components.empty() &&
!(components.back() == "..")) {
if (components.back() == ".") {
// To "back up" over a leading . means simply to remove the leading .
components.pop_back();
components.push_back(component);
} else {
// Back up normally.
components.pop_back();
}
} else {
components.push_back(component);
}
p = slash;
while (p < _filename.length() && _filename[p] == '/') {
p++;
}
}
// Now reassemble the filename.
string result;
if (global) {
result = "/";
}
if (!components.empty()) {
result += components[0];
for (int i = 1; i < (int)components.size(); i++) {
result += "/" + components[i];
}
}
(*this) = result;
}
/**
* Converts the filename to a fully-qualified pathname from the root (if it is
* a relative pathname), and then standardizes it (see standardize()).
*
* This is sometimes a little problematic, since it may convert the file to
* its 'true' absolute pathname, which could be an ugly NFS-named file,
* irrespective of symbolic links (e.g.
* /.automount/dimbo/root/usr2/fit/people/drose instead of /fit/people/drose);
* besides being ugly, filenames like this may not be consistent across
* multiple different platforms.
*/
void Filename::
make_absolute() {
if (is_local()) {
make_absolute(ExecutionEnvironment::get_cwd());
} else {
standardize();
}
}
/**
* Converts the filename to a fully-qualified filename from the root (if it is
* a relative filename), and then standardizes it (see standardize()). This
* flavor accepts a specific starting directory that the filename is known to
* be relative to.
*/
void Filename::
make_absolute(const Filename &start_directory) {
if (is_local()) {
Filename new_filename(start_directory, _filename);
new_filename._flags = _flags;
(*this) = new_filename;
}
standardize();
}
/**
* Converts this filename to a canonical name by replacing the directory part
* with the fully-qualified directory part. This is done by changing to that
* directory and calling getcwd().
*
* This has the effect of (a) converting relative paths to absolute paths (but
* see make_absolute() if this is the only effect you want), and (b) always
* resolving a given directory name to the same string, even if different
* symbolic links are traversed, and (c) changing nice symbolic-link paths
* like fit/people/drose to ugly NFS automounter names like
* hosts/dimbo/usr2/fit/people/drose. This can be troubling, but sometimes
* this is exactly what you want, particularly if you're about to call
* make_relative_to() between two filenames.
*
* The return value is true if successful, or false on failure (usually
* because the directory name does not exist or cannot be chdir'ed into).
*/
bool Filename::
make_canonical() {
if (empty()) {
// An empty filename is a special case. This doesn't name anything.
return false;
}
if (get_fullpath() == "/") {
// The root directory is a special case.
return true;
}
#ifndef WIN32
// Use realpath in order to resolve symlinks properly
char newpath [PATH_MAX + 1];
if (realpath(c_str(), newpath) != nullptr) {
Filename newpath_fn(newpath);
newpath_fn._flags = _flags;
(*this) = newpath_fn;
}
#endif
Filename cwd = ExecutionEnvironment::get_cwd();
if (!r_make_canonical(cwd)) {
return false;
}
return make_true_case();
}
/**
* On a case-insensitive operating system (e.g. Windows), this method looks
* up the file in the file system and resets the Filename to represent the
* actual case of the file as it exists on the disk. The return value is true
* if the file exists and the conversion can be made, or false if there is
* some error.
*
* On a case-sensitive operating system, this method does nothing and always
* returns true.
*
* An empty filename is considered to exist in this case.
*/
bool Filename::
make_true_case() {
assert(!get_pattern());
if (empty()) {
return true;
}
#ifdef WIN32
wstring os_specific = to_os_specific_w();
// First, we have to convert it to its short name, then back to its long
// name--that seems to be the trick to force Windows to throw away the case
// we give it and get the actual file case.
wchar_t short_name[MAX_PATH + 1];
DWORD l = GetShortPathNameW(os_specific.c_str(), short_name, MAX_PATH + 1);
if (l == 0) {
// Couldn't query the path name for some reason. Probably the file didn't
// exist.
return false;
}
// According to the Windows docs, l will return a value greater than the
// specified length if the short_name length wasn't enough--but also
// according to the Windows docs, MAX_PATH will always be enough.
assert(l < MAX_PATH + 1);
wchar_t long_name[MAX_PATH + 1];
l = GetLongPathNameW(short_name, long_name, MAX_PATH + 1);
if (l == 0) {
// Couldn't query the path name for some reason. Probably the file didn't
// exist.
return false;
}
assert(l < MAX_PATH + 1);
Filename true_case = Filename::from_os_specific_w(long_name);
// Now sanity-check the true-case filename. If it's not the same as the
// source file, except for case, reject it.
wstring orig_filename = get_fullpath_w();
wstring new_filename = true_case.get_fullpath_w();
bool match = (orig_filename.length() == new_filename.length());
for (size_t i = 0; i < orig_filename.length() && match; ++i) {
match = (TextEncoder::unicode_tolower(orig_filename[i]) == TextEncoder::unicode_tolower(new_filename[i]));
}
if (!match) {
// Something went wrong. Keep the original filename, assume it was the
// correct case after all. We return true because the filename is good.
return true;
}
true_case._flags = _flags;
(*this) = true_case;
return true;
#else // WIN32
return true;
#endif // WIN32
}
/**
* Converts the filename from our generic Unix-like convention (forward
* slashes starting with the root at '/') to the corresponding filename in the
* local operating system (slashes in the appropriate direction, starting with
* the root at C:\, for instance). Returns the string representing the
* converted filename, but does not change the Filename itself.
*
* See also from_os_specific().
*/
string Filename::
to_os_specific() const {
assert(!get_pattern());
if (empty()) {
return string();
}
Filename standard(*this);
standard.standardize();
#ifdef IS_OSX
if (get_type() == T_dso) {
std::string workname = standard.get_fullpath();
size_t dot = workname.rfind('.');
if (dot != string::npos) {
if (workname.substr(dot) == ".so") {
string dyLibBase = workname.substr(0, dot)+".dylib";
return dyLibBase;
}
}
}
#endif
#ifdef WIN32
switch (get_type()) {
case T_dso:
return convert_dso_pathname(standard.get_fullpath());
case T_executable:
return convert_executable_pathname(standard.get_fullpath());
default:
return convert_pathname(standard.get_fullpath());
}
#else // WIN32
return standard.c_str();
#endif // WIN32
}
/**
* The wide-string variant on to_os_specific().
*/
wstring Filename::
to_os_specific_w() const {
TextEncoder encoder;
encoder.set_encoding(get_filesystem_encoding());
encoder.set_text(to_os_specific());
return encoder.get_wtext();
}
/**
* This is similar to to_os_specific(), but it is designed to generate a
* filename that can be understood on as many platforms as possible. Since
* Windows can usually understand a forward-slash-delimited filename, this
* means it does the same thing as to_os_specific(), but it uses forward
* slashes instead of backslashes.
*
* This method has a pretty limited use; it should generally be used for
* writing file references to a file that might be read on any operating
* system.
*/
string Filename::
to_os_generic() const {
assert(!get_pattern());
#ifdef WIN32
return back_to_front_slash(to_os_specific());
#else // WIN32
return to_os_specific();
#endif // WIN32
}
/**
* This works like to_os_generic(), but it returns the "short name" version of
* the filename, if it exists, or the original filename otherwise.
*
* On Windows platforms, this returns the 8.3 filename version of the given
* filename, if the file exists, and the same thing as to_os_specific()
* otherwise. On non-Windows platforms, this always returns the same thing as
* to_os_specific().
*/
string Filename::
to_os_short_name() const {
assert(!get_pattern());
#ifdef WIN32
wstring os_specific = to_os_specific_w();
wchar_t short_name[MAX_PATH + 1];
DWORD l = GetShortPathNameW(os_specific.c_str(), short_name, MAX_PATH + 1);
if (l == 0) {
// Couldn't query the path name for some reason. Probably the file didn't
// exist.
return to_os_specific();
}
// According to the Windows docs, l will return a value greater than the
// specified length if the short_name length wasn't enough--but also
// according to the Windows docs, MAX_PATH will always be enough.
assert(l < MAX_PATH + 1);
TextEncoder encoder;
encoder.set_encoding(get_filesystem_encoding());
encoder.set_wtext(short_name);
return encoder.get_text();
#else // WIN32
return to_os_specific();
#endif // WIN32
}
/**
* This is the opposite of to_os_short_name(): it returns the "long name" of
* the filename, if the filename exists. On non-Windows platforms, this
* returns the same thing as to_os_specific().
*/
string Filename::
to_os_long_name() const {
assert(!get_pattern());
#ifdef WIN32
wstring os_specific = to_os_specific_w();
wchar_t long_name[MAX_PATH + 1];
DWORD l = GetLongPathNameW(os_specific.c_str(), long_name, MAX_PATH + 1);
if (l == 0) {
// Couldn't query the path name for some reason. Probably the file didn't
// exist.
return to_os_specific();
}
assert(l < MAX_PATH + 1);
TextEncoder encoder;
encoder.set_encoding(get_filesystem_encoding());
encoder.set_wtext(long_name);
return encoder.get_text();
#else // WIN32
return to_os_specific();
#endif // WIN32
}
/**
* Returns true if the filename exists on the disk, false otherwise. If the
* type is indicated to be executable, this also tests that the file has
* execute permission.
*/
bool Filename::
exists() const {
#ifdef WIN32_VC
wstring os_specific = get_filename_index(0).to_os_specific_w();
bool exists = false;
DWORD results = GetFileAttributesW(os_specific.c_str());
if (results != -1) {
exists = true;
}
#else // WIN32_VC
string os_specific = get_filename_index(0).to_os_specific();
struct stat this_buf;
bool exists = false;
if (stat(os_specific.c_str(), &this_buf) == 0) {
exists = true;
}
#endif
return exists;
}
/**
* Returns true if the filename exists and is the name of a regular file (i.e.
* not a directory or device), false otherwise.
*/
bool Filename::
is_regular_file() const {
#ifdef WIN32_VC
wstring os_specific = get_filename_index(0).to_os_specific_w();
bool isreg = false;
DWORD results = GetFileAttributesW(os_specific.c_str());
if (results != -1) {
isreg = ((results & (FILE_ATTRIBUTE_DIRECTORY | FILE_ATTRIBUTE_DEVICE)) == 0);
}
#else // WIN32_VC
string os_specific = get_filename_index(0).to_os_specific();
struct stat this_buf;
bool isreg = false;
if (stat(os_specific.c_str(), &this_buf) == 0) {
isreg = S_ISREG(this_buf.st_mode);
}
#endif
return isreg;
}
/**
* Returns true if the filename exists and is either a directory or a regular
* file that can be written to, or false otherwise.
*/
bool Filename::
is_writable() const {
bool writable = false;
#ifdef WIN32_VC
wstring os_specific = get_filename_index(0).to_os_specific_w();
DWORD results = GetFileAttributesW(os_specific.c_str());
if (results != -1) {
if ((results & FILE_ATTRIBUTE_DIRECTORY) != 0) {
// Assume directories are writable.
writable = true;
} else if ((results & FILE_ATTRIBUTE_READONLY) == 0) {
// Not read-only means writable.
writable = true;
}
}
#else // WIN32_VC
string os_specific = get_filename_index(0).to_os_specific();
if (access(os_specific.c_str(), W_OK) == 0) {
writable = true;
}
#endif
return writable;
}
/**
* Returns true if the filename exists and is a directory name, false
* otherwise.
*/
bool Filename::
is_directory() const {
#ifdef WIN32_VC
wstring os_specific = get_filename_index(0).to_os_specific_w();
bool isdir = false;
DWORD results = GetFileAttributesW(os_specific.c_str());
if (results != -1) {
isdir = (results & FILE_ATTRIBUTE_DIRECTORY) != 0;
}
#else // WIN32_VC
string os_specific = get_filename_index(0).to_os_specific();
struct stat this_buf;
bool isdir = false;
if (stat(os_specific.c_str(), &this_buf) == 0) {
isdir = S_ISDIR(this_buf.st_mode);
}
#endif
return isdir;
}
/**
* Returns true if the filename exists and is executable
*/
bool Filename::
is_executable() const {
#ifdef WIN32_VC
// no access() in windows, but to our advantage executables can only end in
// .exe or .com
string extension = get_extension();
if (extension == "exe" || extension == "com") {
return exists();
}
#else /* WIN32_VC */
string os_specific = get_filename_index(0).to_os_specific();
if (access(os_specific.c_str(), X_OK) == 0) {
return true;
}
#endif /* WIN32_VC */
return false;
}
/**
* Returns a number less than zero if the file named by this object is older
* than the given file, zero if they have the same timestamp, or greater than
* zero if this one is newer.
*
* If this_missing_is_old is true, it indicates that a missing file will be
* treated as if it were older than any other file; otherwise, a missing file
* will be treated as if it were newer than any other file. Similarly for
* other_missing_is_old.
*/
int Filename::
compare_timestamps(const Filename &other,
bool this_missing_is_old,
bool other_missing_is_old) const {
#ifdef WIN32_VC
wstring os_specific = get_filename_index(0).to_os_specific_w();
wstring other_os_specific = other.get_filename_index(0).to_os_specific_w();
struct _stat this_buf;
bool this_exists = false;
if (_wstat(os_specific.c_str(), &this_buf) == 0) {
this_exists = true;
}
struct _stat other_buf;
bool other_exists = false;
if (_wstat(other_os_specific.c_str(), &other_buf) == 0) {
other_exists = true;
}
#else // WIN32_VC
string os_specific = get_filename_index(0).to_os_specific();
string other_os_specific = other.get_filename_index(0).to_os_specific();
struct stat this_buf;
bool this_exists = false;
if (stat(os_specific.c_str(), &this_buf) == 0) {
this_exists = true;
}
struct stat other_buf;
bool other_exists = false;
if (stat(other_os_specific.c_str(), &other_buf) == 0) {
other_exists = true;
}
#endif
if (this_exists && other_exists) {
// Both files exist, return the honest time comparison.
return (int)this_buf.st_mtime - (int)other_buf.st_mtime;
} else if (!this_exists && !other_exists) {
// Neither file exists.
if (this_missing_is_old == other_missing_is_old) {
// Both files are either "very old" or "very new".
return 0;
}
if (this_missing_is_old) {
// This file is "very old", the other is "very new".
return -1;
} else {
// This file is "very new", the other is "very old".
return 1;
}
} else if (!this_exists) {
// This file doesn't, the other one does.
return this_missing_is_old ? -1 : 1;
}
// !other_exists
assert(!other_exists);
// This file exists, the other one doesn't.
return other_missing_is_old ? 1 : -1;
}
/**
* Returns a time_t value that represents the time the file was last modified,
* to within whatever precision the operating system records this information
* (on a Windows95 system, for instance, this may only be accurate to within 2
* seconds).
*
* If the timestamp cannot be determined, either because it is not supported
* by the operating system or because there is some error (such as file not
* found), returns 0.
*/
time_t Filename::
get_timestamp() const {
#ifdef WIN32_VC
wstring os_specific = get_filename_index(0).to_os_specific_w();
struct _stat this_buf;
if (_wstat(os_specific.c_str(), &this_buf) == 0) {
return this_buf.st_mtime;
}
#else // WIN32_VC
string os_specific = get_filename_index(0).to_os_specific();
struct stat this_buf;
if (stat(os_specific.c_str(), &this_buf) == 0) {
return this_buf.st_mtime;
}
#endif
return 0;
}
/**
* Returns a time_t value that represents the time the file was last accessed,
* if this information is available. See also get_timestamp(), which returns
* the last modification time.
*/
time_t Filename::
get_access_timestamp() const {
#ifdef WIN32_VC
wstring os_specific = get_filename_index(0).to_os_specific_w();
struct _stat this_buf;
if (_wstat(os_specific.c_str(), &this_buf) == 0) {
return this_buf.st_atime;
}
#else // WIN32_VC
string os_specific = get_filename_index(0).to_os_specific();
struct stat this_buf;
if (stat(os_specific.c_str(), &this_buf) == 0) {
return this_buf.st_atime;
}
#endif
return 0;
}
/**
* Returns the size of the file in bytes, or 0 if there is an error.
*/
std::streamsize Filename::
get_file_size() const {
#ifdef WIN32_VC
wstring os_specific = get_filename_index(0).to_os_specific_w();
struct _stat64 this_buf;
// _wstat() only returns the lower 32 bits of the file size (!). We have to
// call _wstati64() if we actually want the full 64-bit file size.
if (_wstati64(os_specific.c_str(), &this_buf) == 0) {
return this_buf.st_size;
}
#else // WIN32_VC
string os_specific = get_filename_index(0).to_os_specific();
struct stat this_buf;
if (stat(os_specific.c_str(), &this_buf) == 0) {
return this_buf.st_size;
}
#endif
return 0;
}
/**
* Searches the given search path for the filename. If it is found, updates
* the filename to the full pathname found and returns true; otherwise,
* returns false.
*/
bool Filename::
resolve_filename(const DSearchPath &searchpath,
const string &default_extension) {
Filename found;
if (is_local()) {
found = searchpath.find_file(*this);
if (found.empty()) {
// We didn't find it with the given extension; can we try the default
// extension?
if (get_extension().empty() && !default_extension.empty()) {
Filename try_ext = *this;
try_ext.set_extension(default_extension);
found = searchpath.find_file(try_ext);
}
}
} else {
if (exists()) {
// The full pathname exists. Return true.
return true;
} else {
// The full pathname doesn't exist with the given extension; does it
// exist with the default extension?
if (get_extension().empty() && !default_extension.empty()) {
Filename try_ext = *this;
try_ext.set_extension(default_extension);
if (try_ext.exists()) {
found = try_ext;
}
}
}
}
if (!found.empty()) {
(*this) = found;
return true;
}
return false;
}
/**
* Adjusts this filename, which must be a fully-specified pathname beginning
* with a slash, to make it a relative filename, relative to the fully-
* specified directory indicated (which must also begin with, and may or may
* not end with, a slash--a terminating slash is ignored).
*
* This only performs a string comparsion, so it may be wise to call
* make_canonical() on both filenames before calling make_relative_to().
*
* If allow_backups is false, the filename will only be adjusted to be made
* relative if it is already somewhere within or below the indicated
* directory. If allow_backups is true, it will be adjusted in all cases,
* even if this requires putting a series of .. characters before the filename
* --unless it would have to back all the way up to the root.
*
* Returns true if the file was adjusted, false if it was not.
*/
bool Filename::
make_relative_to(Filename directory, bool allow_backups) {
if (_filename.empty() || directory.empty() ||
_filename[0] != '/' || directory[0] != '/') {
return false;
}
standardize();
directory.standardize();
if (directory == "/") {
// Don't be silly.
return false;
}
string rel_to_file = directory.get_fullpath() + "/.";
size_t common = get_common_prefix(rel_to_file);
if (common < 2) {
// Oh, never mind.
return false;
}
string result;
int slashes = count_slashes(rel_to_file.substr(common));
if (slashes > 0 && !allow_backups) {
// Too bad; the file's not under the indicated directory.
return false;
}
for (int i = 0; i < slashes; i++) {
result += "../";
}
result += _filename.substr(common);
(*this) = result;
return true;
}
/**
* Performs the reverse of the resolve_filename() operation: assuming that the
* current filename is fully-specified pathname (i.e. beginning with '/'),
* look on the indicated search path for a directory under which the file can
* be found. When found, adjust the Filename to be relative to the indicated
* directory name.
*
* Returns the index of the directory on the searchpath at which the file was
* found, or -1 if it was not found.
*/
int Filename::
find_on_searchpath(const DSearchPath &searchpath) {
if (_filename.empty() || _filename[0] != '/') {
return -1;
}
size_t num_directories = searchpath.get_num_directories();
for (size_t i = 0; i < num_directories; ++i) {
Filename directory = searchpath.get_directory(i);
directory.make_absolute();
if (make_relative_to(directory, false)) {
return (int)i;
}
}
return -1;
}
/**
* Attempts to open the named filename as if it were a directory and looks for
* the non-hidden files within the directory. Fills the given vector up with
* the sorted list of filenames that are local to this directory.
*
* It is the user's responsibility to ensure that the contents vector is empty
* before making this call; otherwise, the new files will be appended to it.
*
* Returns true on success, false if the directory could not be read for some
* reason.
*/
bool Filename::
scan_directory(vector_string &contents) const {
assert(!get_pattern());
#if defined(WIN32_VC)
// Use Windows' FindFirstFile() FindNextFile() to walk through the list of
// files in a directory.
size_t orig_size = contents.size();
wstring match;
if (empty()) {
match = L"*.*";
} else {
match = to_os_specific_w() + L"\\*.*";
}
WIN32_FIND_DATAW find_data;
HANDLE handle = FindFirstFileW(match.c_str(), &find_data);
if (handle == INVALID_HANDLE_VALUE) {
if (GetLastError() == ERROR_NO_MORE_FILES) {
// No matching files is not an error.
return true;
}
return false;
}
TextEncoder encoder;
encoder.set_encoding(get_filesystem_encoding());
do {
thread_consider_yield();
wstring filename = find_data.cFileName;
if (filename != L"." && filename != L"..") {
encoder.set_wtext(filename);
contents.push_back(encoder.get_text());
}
} while (FindNextFileW(handle, &find_data));
bool scan_ok = (GetLastError() == ERROR_NO_MORE_FILES);
FindClose(handle);
sort(contents.begin() + orig_size, contents.end());
return scan_ok;
#elif defined(PHAVE_DIRENT_H)
// Use Posix's opendir() readdir() to walk through the list of files in a
// directory.
size_t orig_size = contents.size();
string dirname;
if (empty()) {
dirname = ".";
} else {
dirname = _filename;
}
DIR *root = opendir(dirname.c_str());
if (root == nullptr) {
if (errno != ENOTDIR) {
perror(dirname.c_str());
}
return false;
}
struct dirent *d;
d = readdir(root);
while (d != nullptr) {
thread_consider_yield();
if (d->d_name[0] != '.') {
contents.push_back(d->d_name);
}
d = readdir(root);
}
// It turns out to be a mistake to check the value of errno after calling
// readdir(), since it might have been set to non-zero during some internal
// operation of readdir(), even though there wasn't really a problem with
// scanning the directory itself.
/*
if (errno != 0 && errno != ENOENT && errno != ENOTDIR) {
cerr << "Error occurred while scanning directory " << dirname << "\n";
perror(dirname.c_str());
closedir(root);
return false;
}
*/
closedir(root);
sort(contents.begin() + orig_size, contents.end());
return true;
#elif defined(PHAVE_GLOB_H)
// It's hard to imagine a system that provides glob.h but does not provide
// openddir() .. readdir(), but this code is leftover from a time when there
// was an undetected bug in the above readdir() loop, and it works, so we
// might as well keep it around for now.
string dirname;
if (empty()) {
dirname = "*";
} else if (_filename[_filename.length() - 1] == '/') {
dirname = _filename + "*";
} else {
dirname = _filename + "/*"; /* comment to fix emacs syntax hilight */
}
glob_t globbuf;
int r = glob(dirname.c_str(), GLOB_ERR, nullptr, &globbuf);
if (r != 0) {
// Some error processing the match string. If our version of glob.h
// defines GLOB_NOMATCH, then we can differentiate an empty return result
// from some other kind of error.
#ifdef GLOB_NOMATCH
if (r != GLOB_NOMATCH) {
perror(dirname.c_str());
return false;
}
#endif
// Otherwise, all errors mean the same thing: no matches, but otherwise no
// problem.
return true;
}
size_t offset = dirname.size() - 1;
for (int i = 0; globbuf.gl_pathv[i] != nullptr; i++) {
contents.push_back(globbuf.gl_pathv[i] + offset);
}
globfree(&globbuf);
return true;
#else
// Don't know how to scan directories!
return false;
#endif
}
/**
* Opens the indicated ifstream for reading the file, if possible. Returns
* true if successful, false otherwise. This requires the setting of the
* set_text()/set_binary() flags to open the file appropriately as indicated;
* it is an error to call open_read() without first calling one of set_text()
* or set_binary().
*/
bool Filename::
open_read(std::ifstream &stream) const {
assert(!get_pattern());
assert(is_binary_or_text());
ios_openmode open_mode = ios::in;
#ifdef HAVE_IOS_BINARY
// For some reason, some systems (like Irix) don't define ios::binary.
if (!is_text()) {
open_mode |= ios::binary;
}
#endif
stream.clear();
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
stream.open(os_specific.c_str(), open_mode);
#else
string os_specific = to_os_specific();
stream.open(os_specific.c_str(), open_mode);
#endif // WIN32_VC
return (!stream.fail());
}
/**
* Opens the indicated ifstream for writing the file, if possible. Returns
* true if successful, false otherwise. This requires the setting of the
* set_text()/set_binary() flags to open the file appropriately as indicated;
* it is an error to call open_read() without first calling one of set_text()
* or set_binary().
*
* If truncate is true, the file is truncated to zero length upon opening it,
* if it already exists. Otherwise, the file is kept at its original length.
*/
bool Filename::
open_write(std::ofstream &stream, bool truncate) const {
assert(!get_pattern());
assert(is_binary_or_text());
ios_openmode open_mode = ios::out;
if (truncate) {
open_mode |= ios::trunc;
} else {
// Some systems insist on having ios::in set to prevent the file from
// being truncated when we open it. Makes ios::trunc kind of pointless,
// doesn't it? On the other hand, setting ios::in also seems to imply
// ios::nocreate (!), so we should only set this if the file already
// exists.
if (exists()) {
open_mode |= ios::in;
}
}
#ifdef HAVE_IOS_BINARY
// For some reason, some systems (like Irix) don't define ios::binary.
if (!is_text()) {
open_mode |= ios::binary;
}
#endif
stream.clear();
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
#else
string os_specific = to_os_specific();
#endif // WIN32_VC
stream.open(os_specific.c_str(), open_mode);
return (!stream.fail());
}
/**
* Opens the indicated ofstream for writing the file, if possible. Returns
* true if successful, false otherwise. This requires the setting of the
* set_text()/set_binary() flags to open the file appropriately as indicated;
* it is an error to call open_read() without first calling one of set_text()
* or set_binary().
*/
bool Filename::
open_append(std::ofstream &stream) const {
assert(!get_pattern());
assert(is_binary_or_text());
ios_openmode open_mode = ios::app;
#ifdef HAVE_IOS_BINARY
// For some reason, some systems (like Irix) don't define ios::binary.
if (!is_text()) {
open_mode |= ios::binary;
}
#endif
stream.clear();
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
#else
string os_specific = to_os_specific();
#endif // WIN32_VC
stream.open(os_specific.c_str(), open_mode);
return (!stream.fail());
}
/**
* Opens the indicated fstream for read/write access to the file, if possible.
* Returns true if successful, false otherwise. This requires the setting of
* the set_text()/set_binary() flags to open the file appropriately as
* indicated; it is an error to call open_read_write() without first calling
* one of set_text() or set_binary().
*/
bool Filename::
open_read_write(std::fstream &stream, bool truncate) const {
assert(!get_pattern());
assert(is_binary_or_text());
ios_openmode open_mode = ios::out | ios::in;
if (truncate) {
open_mode |= ios::trunc;
}
// Since ios::in also seems to imply ios::nocreate (!), we must guarantee
// the file already exists before we try to open it.
if (!exists()) {
touch();
}
#ifdef HAVE_IOS_BINARY
// For some reason, some systems (like Irix) don't define ios::binary.
if (!is_text()) {
open_mode |= ios::binary;
}
#endif
stream.clear();
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
#else
string os_specific = to_os_specific();
#endif // WIN32_VC
stream.open(os_specific.c_str(), open_mode);
return (!stream.fail());
}
/**
* Opens the indicated ifstream for reading and writing the file, if possible;
* writes are appended to the end of the file. Returns true if successful,
* false otherwise. This requires the setting of the set_text()/set_binary()
* flags to open the file appropriately as indicated; it is an error to call
* open_read() without first calling one of set_text() or set_binary().
*/
bool Filename::
open_read_append(std::fstream &stream) const {
assert(!get_pattern());
assert(is_binary_or_text());
ios_openmode open_mode = ios::app | ios::in;
#ifdef HAVE_IOS_BINARY
// For some reason, some systems (like Irix) don't define ios::binary.
if (!is_text()) {
open_mode |= ios::binary;
}
#endif
stream.clear();
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
#else
string os_specific = to_os_specific();
#endif // WIN32_VC
stream.open(os_specific.c_str(), open_mode);
return (!stream.fail());
}
#ifdef USE_PANDAFILESTREAM
/**
* Opens the indicated pifstream for reading the file, if possible. Returns
* true if successful, false otherwise. This requires the setting of the
* set_text()/set_binary() flags to open the file appropriately as indicated;
* it is an error to call open_read() without first calling one of set_text()
* or set_binary().
*/
bool Filename::
open_read(pifstream &stream) const {
assert(!get_pattern());
assert(is_binary_or_text());
ios_openmode open_mode = ios::in;
#ifdef HAVE_IOS_BINARY
// For some reason, some systems (like Irix) don't define ios::binary.
if (!is_text()) {
open_mode |= ios::binary;
}
#endif
string os_specific = to_os_specific();
stream.clear();
stream.open(os_specific.c_str(), open_mode);
return (!stream.fail());
}
#endif // USE_PANDAFILESTREAM
#ifdef USE_PANDAFILESTREAM
/**
* Opens the indicated pifstream for writing the file, if possible. Returns
* true if successful, false otherwise. This requires the setting of the
* set_text()/set_binary() flags to open the file appropriately as indicated;
* it is an error to call open_read() without first calling one of set_text()
* or set_binary().
*
* If truncate is true, the file is truncated to zero length upon opening it,
* if it already exists. Otherwise, the file is kept at its original length.
*/
bool Filename::
open_write(pofstream &stream, bool truncate) const {
assert(!get_pattern());
assert(is_binary_or_text());
ios_openmode open_mode = ios::out;
if (truncate) {
open_mode |= ios::trunc;
} else {
// Some systems insist on having ios::in set to prevent the file from
// being truncated when we open it. Makes ios::trunc kind of pointless,
// doesn't it? On the other hand, setting ios::in also seems to imply
// ios::nocreate (!), so we should only set this if the file already
// exists.
if (exists()) {
open_mode |= ios::in;
}
}
#ifdef HAVE_IOS_BINARY
// For some reason, some systems (like Irix) don't define ios::binary.
if (!is_text()) {
open_mode |= ios::binary;
}
#endif
stream.clear();
string os_specific = to_os_specific();
stream.open(os_specific.c_str(), open_mode);
return (!stream.fail());
}
#endif // USE_PANDAFILESTREAM
#ifdef USE_PANDAFILESTREAM
/**
* Opens the indicated pifstream for writing the file, if possible. Returns
* true if successful, false otherwise. This requires the setting of the
* set_text()/set_binary() flags to open the file appropriately as indicated;
* it is an error to call open_read() without first calling one of set_text()
* or set_binary().
*/
bool Filename::
open_append(pofstream &stream) const {
assert(!get_pattern());
assert(is_binary_or_text());
ios_openmode open_mode = ios::app;
#ifdef HAVE_IOS_BINARY
// For some reason, some systems (like Irix) don't define ios::binary.
if (!is_text()) {
open_mode |= ios::binary;
}
#endif
stream.clear();
string os_specific = to_os_specific();
stream.open(os_specific.c_str(), open_mode);
return (!stream.fail());
}
#endif // USE_PANDAFILESTREAM
#ifdef USE_PANDAFILESTREAM
/**
* Opens the indicated fstream for read/write access to the file, if possible.
* Returns true if successful, false otherwise. This requires the setting of
* the set_text()/set_binary() flags to open the file appropriately as
* indicated; it is an error to call open_read_write() without first calling
* one of set_text() or set_binary().
*/
bool Filename::
open_read_write(pfstream &stream, bool truncate) const {
assert(!get_pattern());
assert(is_binary_or_text());
ios_openmode open_mode = ios::out | ios::in;
if (truncate) {
open_mode |= ios::trunc;
}
// Since ios::in also seems to imply ios::nocreate (!), we must guarantee
// the file already exists before we try to open it.
if (!exists()) {
touch();
}
#ifdef HAVE_IOS_BINARY
// For some reason, some systems (like Irix) don't define ios::binary.
if (!is_text()) {
open_mode |= ios::binary;
}
#endif
stream.clear();
string os_specific = to_os_specific();
stream.open(os_specific.c_str(), open_mode);
return (!stream.fail());
}
#endif // USE_PANDAFILESTREAM
#ifdef USE_PANDAFILESTREAM
/**
* Opens the indicated pfstream for reading and writing the file, if possible;
* writes are appended to the end of the file. Returns true if successful,
* false otherwise. This requires the setting of the set_text()/set_binary()
* flags to open the file appropriately as indicated; it is an error to call
* open_read() without first calling one of set_text() or set_binary().
*/
bool Filename::
open_read_append(pfstream &stream) const {
assert(!get_pattern());
assert(is_binary_or_text());
ios_openmode open_mode = ios::app | ios::in;
#ifdef HAVE_IOS_BINARY
// For some reason, some systems (like Irix) don't define ios::binary.
if (!is_text()) {
open_mode |= ios::binary;
}
#endif
stream.clear();
string os_specific = to_os_specific();
stream.open(os_specific.c_str(), open_mode);
return (!stream.fail());
}
#endif // USE_PANDAFILESTREAM
/**
* Updates the modification time of the file to the current time. If the file
* does not already exist, it will be created. Returns true if successful,
* false if there is an error.
*/
bool Filename::
touch() const {
assert(!get_pattern());
#ifdef WIN32_VC
// In Windows, we have to use the Windows API to do this reliably.
// First, guarantee the file exists (and also get its handle).
wstring os_specific = to_os_specific_w();
HANDLE fhandle;
fhandle = CreateFileW(os_specific.c_str(), GENERIC_WRITE, FILE_SHARE_WRITE,
nullptr, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, nullptr);
if (fhandle == INVALID_HANDLE_VALUE) {
return false;
}
// Now update the file time and date.
SYSTEMTIME sysnow;
FILETIME ftnow;
GetSystemTime(&sysnow);
if (!SystemTimeToFileTime(&sysnow, &ftnow)) {
CloseHandle(fhandle);
return false;
}
if (!SetFileTime(fhandle, nullptr, nullptr, &ftnow)) {
CloseHandle(fhandle);
return false;
}
CloseHandle(fhandle);
return true;
#elif defined(PHAVE_UTIME_H)
// Most Unix systems can do this explicitly.
string os_specific = to_os_specific();
#ifdef HAVE_CYGWIN
// In the Cygwin case, it seems we need to be sure to use the Cygwin-style
// name; some broken utime() implementation. That's almost the same thing
// as the original Panda-style name, but not exactly, so we first convert
// the Panda name to a Windows name, then convert it back to Cygwin, to
// ensure we get it exactly right by Cygwin rules.
{
char result[4096] = "";
cygwin_conv_to_posix_path(os_specific.c_str(), result);
os_specific = result;
}
#endif // HAVE_CYGWIN
int result = utime(os_specific.c_str(), nullptr);
if (result < 0) {
if (errno == ENOENT) {
// So the file doesn't already exist; create it.
int fd = creat(os_specific.c_str(), 0666);
if (fd < 0) {
perror(os_specific.c_str());
return false;
}
close(fd);
return true;
}
perror(os_specific.c_str());
return false;
}
return true;
#else // WIN32, PHAVE_UTIME_H
// Other systems may not have an explicit control over the modification
// time. For these systems, we'll just temporarily open the file in append
// mode, then close it again (it gets closed when the pfstream goes out of
// scope).
pfstream file;
return open_append(file);
#endif // WIN32, PHAVE_UTIME_H
}
/**
* Changes directory to the specified location. Returns true if successful,
* false if failure.
*/
bool Filename::
chdir() const {
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
return (_wchdir(os_specific.c_str()) >= 0);
#else
string os_specific = to_os_specific();
return (::chdir(os_specific.c_str()) >= 0);
#endif // WIN32_VC
}
/**
* Permanently deletes the file associated with the filename, if possible.
* Returns true if successful, false if failure (for instance, because the
* file did not exist, or because permissions were inadequate).
*/
bool Filename::
unlink() const {
assert(!get_pattern());
#ifdef WIN32_VC
// Windows can't delete a file if it's read-only. Weird.
wstring os_specific = to_os_specific_w();
_wchmod(os_specific.c_str(), 0644);
return (_wunlink(os_specific.c_str()) == 0);
#else
string os_specific = to_os_specific();
return (::unlink(os_specific.c_str()) == 0);
#endif // WIN32_VC
}
/**
* Renames the file to the indicated new filename. If the new filename is in
* a different directory, this will perform a move. Returns true if
* successful, false on failure.
*/
bool Filename::
rename_to(const Filename &other) const {
assert(!get_pattern());
if (*this == other) {
// Trivial success.
return true;
}
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
wstring other_os_specific = other.to_os_specific_w();
if (_wrename(os_specific.c_str(),
other_os_specific.c_str()) == 0) {
// Successfully renamed.
return true;
}
// The above might fail if we have tried to move a file to a different
// filesystem. In this case, copy the file into the same directory first,
// and then rename it.
string dirname = other.get_dirname();
if (dirname.empty()) {
dirname = ".";
}
Filename temp = Filename::temporary(dirname, "");
temp.set_binary();
if (!Filename::binary_filename(*this).copy_to(temp)) {
return false;
}
wstring temp_os_specific = temp.to_os_specific_w();
if (_wrename(temp_os_specific.c_str(),
other_os_specific.c_str()) == 0) {
// Successfully renamed.
unlink();
return true;
}
// Try unlinking the target first.
other.unlink();
if (_wrename(temp_os_specific.c_str(),
other_os_specific.c_str()) == 0) {
// Successfully renamed.
unlink();
return true;
}
#else // WIN32_VC
string os_specific = to_os_specific();
string other_os_specific = other.to_os_specific();
if (rename(os_specific.c_str(),
other_os_specific.c_str()) == 0) {
// Successfully renamed.
return true;
}
// The above might fail if we have tried to move a file to a different
// filesystem. In this case, copy the file into the same directory first,
// and then rename it.
string dirname = other.get_dirname();
if (dirname.empty()) {
dirname = ".";
}
Filename temp = Filename::temporary(dirname, "");
temp.set_binary();
if (!Filename::binary_filename(*this).copy_to(temp)) {
return false;
}
string temp_os_specific = temp.to_os_specific();
if (rename(temp_os_specific.c_str(),
other_os_specific.c_str()) == 0) {
// Successfully renamed.
unlink();
return true;
}
// Try unlinking the target first.
other.unlink();
if (rename(temp_os_specific.c_str(),
other_os_specific.c_str()) == 0) {
// Successfully renamed.
unlink();
return true;
}
#endif // WIN32_VC
// Failed.
temp.unlink();
return false;
}
/**
* Copies the file to the indicated new filename, by reading the contents and
* writing it to the new file. Returns true if successful, false on failure.
* The copy is always binary, regardless of the filename settings.
*/
bool Filename::
copy_to(const Filename &other) const {
Filename this_filename = Filename::binary_filename(*this);
pifstream in;
if (!this_filename.open_read(in)) {
return false;
}
Filename other_filename = Filename::binary_filename(other);
pofstream out;
if (!other_filename.open_write(out)) {
return false;
}
static const size_t buffer_size = 4096;
char buffer[buffer_size];
in.read(buffer, buffer_size);
size_t count = in.gcount();
while (count != 0) {
out.write(buffer, count);
if (out.fail()) {
other.unlink();
return false;
}
in.read(buffer, buffer_size);
count = in.gcount();
}
if (!in.eof()) {
other.unlink();
return false;
}
return true;
}
/**
* Creates all the directories in the path to the file specified in the
* filename, except for the basename itself. This assumes that the Filename
* contains the name of a file, not a directory name; it ensures that the
* directory containing the file exists.
*
* However, if the filename ends in a slash, it assumes the Filename
* represents the name of a directory, and creates all the paths.
*/
bool Filename::
make_dir() const {
assert(!get_pattern());
if (empty()) {
return false;
}
Filename path;
if (_filename[_filename.length() - 1] == '/') {
// The Filename ends in a slash; it represents a directory.
path = (*this);
} else {
// The Filename does not end in a slash; it represents a file.
path = get_dirname();
}
if (path.empty()) {
return false;
}
string dirname = path.get_fullpath();
// First, make sure everything up to the last path is known. We don't care
// too much if any of these fail; maybe they failed because the directory
// was already there.
size_t slash = dirname.find('/');
while (slash != string::npos) {
Filename component(dirname.substr(0, slash));
#ifdef WIN32_VC
wstring os_specific = component.to_os_specific_w();
_wmkdir(os_specific.c_str());
#else
string os_specific = component.to_os_specific();
::mkdir(os_specific.c_str(), 0777);
#endif // WIN32_VC
slash = dirname.find('/', slash + 1);
}
// Now make the last one, and check the return value.
Filename component(dirname);
#ifdef WIN32_VC
wstring os_specific = component.to_os_specific_w();
int result = _wmkdir(os_specific.c_str());
#else
string os_specific = component.to_os_specific();
int result = ::mkdir(os_specific.c_str(), 0777);
#endif // WIN32_VC
return (result == 0);
}
/**
* Creates the directory named by this filename. Unlike make_dir(), this
* assumes that the Filename contains the directory name itself. Also, parent
* directories are not automatically created; this function fails if any
* parent directory is missing.
*/
bool Filename::
mkdir() const {
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
int result = _wmkdir(os_specific.c_str());
#else
string os_specific = to_os_specific();
int result = ::mkdir(os_specific.c_str(), 0777);
#endif // WIN32_VC
return (result == 0);
}
/**
* The inverse of mkdir(): this removes the directory named by this Filename,
* if it is in fact a directory.
*/
bool Filename::
rmdir() const {
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
int result = _wrmdir(os_specific.c_str());
if (result != 0) {
// Windows may require the directory to be writable before we can remove
// it.
_wchmod(os_specific.c_str(), 0777);
result = _wrmdir(os_specific.c_str());
}
#else // WIN32_VC
string os_specific = to_os_specific();
int result = ::rmdir(os_specific.c_str());
#endif // WIN32_VC
return (result == 0);
}
/**
* Returns a hash code that attempts to be mostly unique for different
* Filenames.
*/
int Filename::
get_hash() const {
static const int primes[] = {
2, 3, 5, 7, 11, 13, 17, 19, 23, 29,
31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
73, 79, 83, 89, 97, 101, 103, 107, 109, 113,
127, 131, 137, 139, 149, 151, 157, 163, 167, 173,
179, 181, 191, 193, 197, 199, 211, 223, 227, 229,
233, 239, 241, 251, 257, 263, 269, 271, 277, 281,
283, 293, 307, 311, 313, 317, 331, 337, 347, 349,
353, 359, 367, 373, 379, 383, 389, 397, 401, 409,
419, 421, 431, 433, 439, 443, 449, 457, 461, 463,
467, 479, 487, 491, 499, 503, 509, 521, 523, 541,
547, 557, 563, 569, 571, 577, 587, 593, 599, 601,
607, 613, 617, 619, 631, 641, 643, 647, 653, 659,
661, 673, 677, 683, 691, 701, 709, 719, 727, 733,
739, 743, 751, 757, 761, 769, 773, 787, 797, 809,
811, 821, 823, 827, 829, 839, 853, 857, 859, 863,
877, 881, 883, 887, 907, 911, 919, 929, 937, 941,
947, 953, 967, 971, 977, 983, 991, 997
};
static const size_t num_primes = sizeof(primes) / sizeof(int);
int hash = 0;
for (size_t i = 0; i < _filename.size(); ++i) {
hash += (int)_filename[i] * primes[i % num_primes];
}
return hash;
}
/**
* Uses native file-locking mechanisms to atomically replace the contents of a
* (small) file with the specified contents, assuming it hasn't changed since
* the last time the file was read.
*
* This is designed to be similar to AtomicAdjust::compare_and_exchange().
* The method writes new_contents to the file, completely replacing the
* original contents; but only if the original contents exactly matched
* old_contents. If the file was modified, returns true. If, however, the
* original contents of the file did not exactly match old_contents, then the
* file is not modified, and false is returned. In either case, orig_contents
* is filled with the original contents of the file.
*
* If the file does not exist, it is implicitly created, and its original
* contents are empty.
*
* If an I/O error occurs on write, some of the file may or may not have been
* written, and false is returned.
*
* Expressed in pseudo-code, the logic is:
*
* orig_contents = file.read(); if (orig_contents == old_contents) {
* file.write(new_contents); return true; } return false;
*
* The operation is guaranteed to be atomic only if the only operations that
* read and write to this file are atomic_compare_and_exchange_contents() and
* atomic_read_contents().
*/
bool Filename::
atomic_compare_and_exchange_contents(string &orig_contents,
const string &old_contents,
const string &new_contents) const {
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
HANDLE hfile = CreateFileW(os_specific.c_str(), GENERIC_READ | GENERIC_WRITE,
0, nullptr, OPEN_ALWAYS,
FILE_ATTRIBUTE_NORMAL, nullptr);
while (hfile == INVALID_HANDLE_VALUE) {
DWORD error = GetLastError();
if (error == ERROR_SHARING_VIOLATION) {
// If the file is locked by another process, yield and try again.
Sleep(0);
hfile = CreateFileW(os_specific.c_str(), GENERIC_READ | GENERIC_WRITE,
0, nullptr, OPEN_ALWAYS,
FILE_ATTRIBUTE_NORMAL, nullptr);
} else {
cerr << "Couldn't open file: " << os_specific
<< ", error " << error << "\n";
return false;
}
}
if (hfile == INVALID_HANDLE_VALUE) {
cerr << "Couldn't open file: " << os_specific
<< ", error " << GetLastError() << "\n";
return false;
}
static const size_t buf_size = 512;
char buf[buf_size];
orig_contents = string();
DWORD bytes_read;
if (!ReadFile(hfile, buf, buf_size, &bytes_read, nullptr)) {
cerr << "Error reading file: " << os_specific
<< ", error " << GetLastError() << "\n";
CloseHandle(hfile);
return false;
}
while (bytes_read > 0) {
orig_contents += string(buf, bytes_read);
if (!ReadFile(hfile, buf, buf_size, &bytes_read, nullptr)) {
cerr << "Error reading file: " << os_specific
<< ", error " << GetLastError() << "\n";
CloseHandle(hfile);
return false;
}
}
bool match = false;
if (orig_contents == old_contents) {
match = true;
SetFilePointer(hfile, 0, 0, FILE_BEGIN);
DWORD bytes_written;
if (!WriteFile(hfile, new_contents.data(), new_contents.size(),
&bytes_written, nullptr)) {
cerr << "Error writing file: " << os_specific
<< ", error " << GetLastError() << "\n";
CloseHandle(hfile);
return false;
}
}
CloseHandle(hfile);
return match;
#else // WIN32_VC
string os_specific = to_os_specific();
int fd = open(os_specific.c_str(), O_RDWR | O_CREAT, 0666);
if (fd < 0) {
perror(os_specific.c_str());
return false;
}
static const size_t buf_size = 512;
char buf[buf_size];
orig_contents = string();
#ifdef PHAVE_LOCKF
if (lockf(fd, F_LOCK, 0) != 0) {
#else
if (flock(fd, LOCK_EX) != 0) {
#endif
perror(os_specific.c_str());
close(fd);
return false;
}
ssize_t bytes_read = read(fd, buf, buf_size);
while (bytes_read > 0) {
orig_contents += string(buf, bytes_read);
bytes_read = read(fd, buf, buf_size);
}
if (bytes_read < 0) {
perror(os_specific.c_str());
close(fd);
return false;
}
bool match = false;
if (orig_contents == old_contents) {
match = true;
lseek(fd, 0, SEEK_SET);
ssize_t bytes_written = write(fd, new_contents.data(), new_contents.size());
if (bytes_written < 0) {
perror(os_specific.c_str());
close(fd);
return false;
}
}
if (close(fd) < 0) {
perror(os_specific.c_str());
return false;
}
return match;
#endif // WIN32_VC
}
/**
* Uses native file-locking mechanisms to atomically read the contents of a
* (small) file. This is the only way to read a file protected by
* atomic_compare_and_exchange_contents(), and be confident that the read
* operation is actually atomic with respect to that method.
*
* If the file does not exist, it is implicitly created, and its contents are
* empty.
*
* If the file is read successfully, fills its contents in the indicated
* string, and returns true. If the file cannot be read, returns false.
*/
bool Filename::
atomic_read_contents(string &contents) const {
#ifdef WIN32_VC
wstring os_specific = to_os_specific_w();
HANDLE hfile = CreateFileW(os_specific.c_str(), GENERIC_READ,
FILE_SHARE_READ, nullptr, OPEN_ALWAYS,
FILE_ATTRIBUTE_NORMAL, nullptr);
while (hfile == INVALID_HANDLE_VALUE) {
DWORD error = GetLastError();
if (error == ERROR_SHARING_VIOLATION) {
// If the file is locked by another process, yield and try again.
Sleep(0);
hfile = CreateFileW(os_specific.c_str(), GENERIC_READ,
FILE_SHARE_READ, nullptr, OPEN_ALWAYS,
FILE_ATTRIBUTE_NORMAL, nullptr);
} else {
cerr << "Couldn't open file: " << os_specific
<< ", error " << error << "\n";
return false;
}
}
static const size_t buf_size = 512;
char buf[buf_size];
contents = string();
DWORD bytes_read;
if (!ReadFile(hfile, buf, buf_size, &bytes_read, nullptr)) {
cerr << "Error reading file: " << os_specific
<< ", error " << GetLastError() << "\n";
CloseHandle(hfile);
return false;
}
while (bytes_read > 0) {
contents += string(buf, bytes_read);
if (!ReadFile(hfile, buf, buf_size, &bytes_read, nullptr)) {
cerr << "Error reading file: " << os_specific
<< ", error " << GetLastError() << "\n";
CloseHandle(hfile);
return false;
}
}
CloseHandle(hfile);
return true;
#else // WIN32_VC
string os_specific = to_os_specific();
int fd = open(os_specific.c_str(), O_RDWR | O_CREAT, 0666);
if (fd < 0) {
perror(os_specific.c_str());
return false;
}
static const size_t buf_size = 512;
char buf[buf_size];
contents = string();
#ifdef PHAVE_LOCKF
if (lockf(fd, F_LOCK, 0) != 0) {
#else
if (flock(fd, LOCK_EX) != 0) {
#endif
perror(os_specific.c_str());
close(fd);
return false;
}
ssize_t bytes_read = read(fd, buf, buf_size);
while (bytes_read > 0) {
contents += string(buf, bytes_read);
bytes_read = read(fd, buf, buf_size);
}
if (bytes_read < 0) {
perror(os_specific.c_str());
close(fd);
return false;
}
close(fd);
return true;
#endif // WIN32_VC
}
/**
* After the string has been reassigned, search for the slash marking the
* beginning of the basename, and set _dirname_end and _basename_start
* correctly.
*/
void Filename::
locate_basename() {
// Scan for the last slash, which marks the end of the directory part.
if (_filename.empty()) {
_dirname_end = 0;
_basename_start = 0;
} else {
string::size_type slash = _filename.rfind('/');
if (slash != string::npos) {
_basename_start = slash + 1;
_dirname_end = _basename_start;
// One exception: in case there are multiple slashes in a row, we want
// to treat them as a single slash. The directory therefore actually
// ends at the first of these; back up a bit.
while (_dirname_end > 0 && _filename[_dirname_end-1] == '/') {
_dirname_end--;
}
// Another exception: if the dirname was nothing but slashes, it was the
// root directory, or itself. In this case the dirname does include
// the terminal slash (of course).
if (_dirname_end == 0) {
_dirname_end = 1;
}
} else {
_dirname_end = 0;
_basename_start = 0;
}
}
// Now:
// _dirname_end is the last slash character, or 0 if there are no slash
// characters.
// _basename_start is the character after the last slash character, or 0 if
// there are no slash characters.
}
/**
* Once the end of the directory prefix has been found, and _dirname_end and
* _basename_start are set correctly, search for the dot marking the beginning
* of the extension, and set _basename_end and _extension_start correctly.
*/
void Filename::
locate_extension() {
// Now scan for the last dot after that slash.
if (_filename.empty()) {
_basename_end = string::npos;
_extension_start = string::npos;
} else {
string::size_type dot = _filename.length() - 1;
while (dot+1 > _basename_start && _filename[dot] != '.') {
--dot;
}
if (dot+1 > _basename_start) {
_basename_end = dot;
_extension_start = dot + 1;
} else {
_basename_end = string::npos;
_extension_start = string::npos;
}
}
// Now:
// _basename_end is the last dot, or npos if there is no dot.
// _extension_start is the character after the last dot, or npos if there is
// no dot.
}
/**
* Identifies the part of the filename that contains the sequence of hash
* marks, if any.
*/
void Filename::
locate_hash() {
if (!get_pattern()) {
// If it's not a pattern-type filename, these are always set to the end of
// the string.
_hash_end = string::npos;
_hash_start = string::npos;
} else {
// If it is a pattern-type filename, we must search for the hash marks,
// which could be anywhere (but are usually toward the end).
_hash_end = _filename.rfind('#');
if (_hash_end == string::npos) {
_hash_end = string::npos;
_hash_start = string::npos;
} else {
_hash_start = _hash_end;
++_hash_end;
while (_hash_start > 0 && _filename[_hash_start - 1] == '#') {
--_hash_start;
}
}
}
}
/**
* Returns the length of the longest common initial substring of this string
* and the other one that ends in a slash. This is the lowest directory
* common to both filenames.
*/
size_t Filename::
get_common_prefix(const string &other) const {
size_t len = 0;
// First, get the length of the common initial substring.
while (len < length() && len < other.length() &&
_filename[len] == other[len]) {
len++;
}
// Now insist that it ends in a slash.
while (len > 0 && _filename[len-1] != '/') {
len--;
}
return len;
}
/**
* Returns the number of non-consecutive slashes in the indicated string, not
* counting a terminal slash.
*/
int Filename::
count_slashes(const string &str) {
int count = 0;
string::const_iterator si;
si = str.begin();
while (si != str.end()) {
if (*si == '/') {
count++;
// Skip consecutive slashes.
++si;
while (*si == '/') {
++si;
}
if (si == str.end()) {
// Oops, that was a terminal slash. Don't count it.
count--;
}
} else {
++si;
}
}
return count;
}
/**
* The recursive implementation of make_canonical().
*/
bool Filename::
r_make_canonical(const Filename &cwd) {
if (get_fullpath() == "/") {
// If we reached the root, the whole path doesn't exist. Report failure.
return false;
}
#ifdef WIN32_VC
// First, try to cd to the filename directly.
wstring os_specific = to_os_specific_w();
if (_wchdir(os_specific.c_str()) >= 0) {
// That worked, save the full path string.
(*this) = ExecutionEnvironment::get_cwd();
// And restore the current working directory.
wstring osdir = cwd.to_os_specific_w();
if (_wchdir(osdir.c_str()) < 0) {
cerr << "Error! Cannot change back to " << osdir << "\n";
}
return true;
}
#else // WIN32_VC
// First, try to cd to the filename directly.
string os_specific = to_os_specific();
if (::chdir(os_specific.c_str()) >= 0) {
// That worked, save the full path string.
(*this) = ExecutionEnvironment::get_cwd();
// And restore the current working directory.
string osdir = cwd.to_os_specific();
if (::chdir(osdir.c_str()) < 0) {
cerr << "Error! Cannot change back to " << osdir << "\n";
}
return true;
}
#endif // WIN32_VC
// That didn't work; maybe it's not a directory. Recursively go to the
// directory above.
Filename dir(get_dirname());
if (dir.empty()) {
// No dirname means the file is in this directory.
set_dirname(cwd);
return true;
}
if (!dir.r_make_canonical(cwd)) {
return false;
}
set_dirname(dir);
return true;
}