79 lines
1.5 KiB
C++
Executable File
79 lines
1.5 KiB
C++
Executable File
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#include <string.h>
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#include <errno.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include "qtlockedfile.h"
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bool QtLockedFile::lock(LockMode mode, bool block)
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{
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if (!isOpen()) {
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qWarning("QtLockedFile::lock(): file is not opened");
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return false;
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}
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if (mode == NoLock)
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return unlock();
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if (mode == m_lock_mode)
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return true;
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if (m_lock_mode != NoLock)
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unlock();
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struct flock fl;
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fl.l_whence = SEEK_SET;
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fl.l_start = 0;
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fl.l_len = 0;
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fl.l_type = (mode == ReadLock) ? F_RDLCK : F_WRLCK;
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int cmd = block ? F_SETLKW : F_SETLK;
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int ret = fcntl(handle(), cmd, &fl);
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if (ret == -1) {
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if (errno != EINTR && errno != EAGAIN)
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qWarning("QtLockedFile::lock(): fcntl: %s", strerror(errno));
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return false;
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}
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m_lock_mode = mode;
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return true;
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}
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bool QtLockedFile::unlock()
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{
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if (!isOpen()) {
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qWarning("QtLockedFile::unlock(): file is not opened");
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return false;
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}
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if (!isLocked())
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return true;
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struct flock fl;
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fl.l_whence = SEEK_SET;
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fl.l_start = 0;
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fl.l_len = 0;
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fl.l_type = F_UNLCK;
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int ret = fcntl(handle(), F_SETLKW, &fl);
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if (ret == -1) {
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qWarning("QtLockedFile::lock(): fcntl: %s", strerror(errno));
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return false;
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}
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m_lock_mode = NoLock;
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return true;
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}
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QtLockedFile::~QtLockedFile()
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{
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if (isOpen())
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unlock();
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}
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