qtemporaryfile.cpp

奇趣公司比较新的qt/emd版本

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#include "qtemporaryfile.h"

#ifndef QT_NO_TEMPORARYFILE

#include "qplatformdefs.h"
#include "qabstractfileengine.h"
#include "private/qfile_p.h"
#include "private/qabstractfileengine_p.h"
#include "private/qfsfileengine_p.h"

#include <stdlib.h>
#include <errno.h>

#include <sys/stat.h>
#include <sys/types.h>
#include <stdlib.h>
#include <time.h>
#include <ctype.h>
#include <sys/types.h>

#ifdef Q_OS_WIN
#include <process.h>
#if defined(_MSC_VER) && _MSC_VER >= 1400
#include <share.h>
#endif
#endif

/*
 * Copyright (c) 1987, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
static int _gettemp(char *path, int *doopen, int domkdir, int slen)
{
	char *start, *trv, *suffp;
	struct stat sbuf;
	int rval;
#ifdef Q_OS_WIN
    int pid;
#else
	pid_t pid;
#endif

	if (doopen && domkdir) {
		errno = EINVAL;
		return(0);
	}

	for (trv = path; *trv; ++trv)
		;
	trv -= slen;
	suffp = trv;
	--trv;
	if (trv < path) {
		errno = EINVAL;
		return (0);
	}
#if defined(Q_OS_WIN) && defined(_MSC_VER) && _MSC_VER >= 1400
        pid = _getpid();
#else
        pid = getpid();
#endif
	while (trv >= path && *trv == 'X' && pid != 0) {
		*trv-- = (pid % 10) + '0';
		pid /= 10;
        }

#ifndef S_ISDIR
#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#endif

        while (trv >= path && *trv == 'X') {
            char c;

            // CHANGE arc4random() -> random()
            pid = (qrand() & 0xffff) % (26+26);
		if (pid < 26)
			c = pid + 'A';
		else
			c = (pid - 26) + 'a';
		*trv-- = c;
	}
	start = trv + 1;

	/*
	 * check the target directory; if you have six X's and it
	 * doesn't exist this runs for a *very* long time.
	 */
	if (doopen || domkdir) {
		for (;; --trv) {
			if (trv <= path)
				break;
			if (*trv == '/') {
				*trv = '\0';
				rval = stat(path, &sbuf);
				*trv = '/';
				if (rval != 0)
					return(0);
				if (!S_ISDIR(sbuf.st_mode)) {
					errno = ENOTDIR;
					return(0);
				}
				break;
			}
		}
	}

	for (;;) {
		if (doopen) {
#if defined(Q_OS_WIN) && defined(_MSC_VER) && _MSC_VER >= 1400
                        if (_sopen_s(doopen, path, QT_OPEN_CREAT|O_EXCL|QT_OPEN_RDWR|QT_OPEN_BINARY
#ifdef QT_LARGEFILE_SUPPORT
                                     |QT_OPEN_LARGEFILE
#endif
                                     , _SH_DENYNO, _S_IREAD | _S_IWRITE)== 0)
#else
                        if ((*doopen =
                            open(path, QT_OPEN_CREAT|O_EXCL|QT_OPEN_RDWR
#ifdef QT_LARGEFILE_SUPPORT
                                 |QT_OPEN_LARGEFILE
#endif
#  if defined(Q_OS_WIN)
                                 |O_BINARY
#  endif
                                 , 0600)) >= 0)
#endif

				return(1);
			if (errno != EEXIST)
				return(0);
		} else if (domkdir) {
#ifdef Q_OS_WIN
                    if (QT_MKDIR(path) == 0)
#else
                    if (mkdir(path, 0700) == 0)
#endif
				return(1);
			if (errno != EEXIST)
				return(0);
            }
#ifndef Q_OS_WIN
            else if (lstat(path, &sbuf))
			return(errno == ENOENT ? 1 : 0);
#endif

		/* tricky little algorwwithm for backward compatibility */
		for (trv = start;;) {
			if (!*trv)
				return (0);
			if (*trv == 'Z') {
				if (trv == suffp)
					return (0);
				*trv++ = 'a';
			} else {
				if (isdigit(*trv))
					*trv = 'a';
				else if (*trv == 'z')	/* inc from z to A */
					*trv = 'A';
				else {
					if (trv == suffp)
						return (0);
					++*trv;
				}
				break;
			}
		}
	}
	/*NOTREACHED*/
}

static int qt_mkstemps(char *path, int slen)
{
	int fd;
	return (_gettemp(path, &fd, 0, slen) ? fd : -1);
}

//************* QTemporaryFileEngine
class QTemporaryFileEngine : public QFSFileEngine
{
    Q_DECLARE_PRIVATE(QFSFileEngine)
public:
    QTemporaryFileEngine(const QString &file) : QFSFileEngine(file) { }
    ~QTemporaryFileEngine();

    bool open(QIODevice::OpenMode flags);
    bool remove();
    bool close();
};

QTemporaryFileEngine::~QTemporaryFileEngine()
{
}

bool QTemporaryFileEngine::open(QIODevice::OpenMode openMode)
{
    Q_D(QFSFileEngine);

    QString qfilename = d->filePath;
    if(!qfilename.contains(QLatin1String("XXXXXX")))
        qfilename += QLatin1String(".XXXXXX");

    int suffixLength = qfilename.length() - (qfilename.lastIndexOf(QLatin1String("XXXXXX"), -1, Qt::CaseSensitive) + 6);
    d->closeFileHandle = true;
    char *filename = qstrdup(qfilename.toLocal8Bit());

    int fd = qt_mkstemps(filename, suffixLength);
    if (fd != -1) {
        // First open the fd as an external file descriptor to
        // initialize the engine properly.
        QFSFileEngine::open(openMode, fd);

        // Allow the engine to close the handle even if it's "external".
        d->closeFileHandle = true;

        // Restore the file names (open() resets them).
        d->filePath = QString::fromLocal8Bit(filename); //changed now!
        d->nativeInitFileName();
        delete [] filename;
        return true;
    }
    delete [] filename;
    setError(errno == EMFILE ? QFile::ResourceError : QFile::OpenError, qt_error_string(errno));
    return false;
}

bool QTemporaryFileEngine::remove()
{
    Q_D(QFSFileEngine);
    // Since the QTemporaryFileEngine::close() does not really close the file,
    // we must explicitly call QFSFileEngine::close() before we remove it.
    QFSFileEngine::close();
    bool removed = QFSFileEngine::remove();
    d->filePath.clear();
    return removed;
}

bool QTemporaryFileEngine::close()
{
    // Don't close the file, just seek to the front.
    seek(0);
    setError(QFile::UnspecifiedError, QString());
    return true;
}

//************* QTemporaryFilePrivate
class QTemporaryFilePrivate : public QFilePrivate
{
    Q_DECLARE_PUBLIC(QTemporaryFile)

protected:
    QTemporaryFilePrivate();
    ~QTemporaryFilePrivate();

    bool autoRemove;
    QString templateName;
    mutable QTemporaryFileEngine *fileEngine;
};

QTemporaryFilePrivate::QTemporaryFilePrivate() : autoRemove(true), fileEngine(0)
{
}