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#include <unistd.h>
#include <fcntl.h>
#include <lib/base/rawfile.h>
#include <lib/base/eerror.h>
eRawFile::eRawFile()
{
m_fd = -1;
m_splitsize = 0;
m_totallength = 0;
m_current_offset = 0;
m_base_offset = 0;
m_last_offset = 0;
m_nrfiles = 0;
m_current_file = 0;
}
eRawFile::~eRawFile()
{
close();
}
int eRawFile::open(const char *filename)
{
close();
m_basename = filename;
scan();
m_current_offset = 0;
m_last_offset = 0;
m_fd = ::open(filename, O_RDONLY | O_LARGEFILE);
return m_fd;
}
void eRawFile::setfd(int fd)
{
close();
m_nrfiles = 1;
m_fd = fd;
}
off_t eRawFile::lseek(off_t offset, int whence)
{
// eDebug("lseek: %lld, %d", offset, whence);
/* if there is only one file, use the native lseek - the file could be growing! */
if (m_nrfiles < 2)
return ::lseek(m_fd, offset, whence);
switch (whence)
{
case SEEK_SET:
m_current_offset = offset;
break;
case SEEK_CUR:
m_current_offset += offset;
break;
case SEEK_END:
m_current_offset = m_totallength + offset;
break;
}
if (m_current_offset < 0)
m_current_offset = 0;
return m_current_offset;
}
int eRawFile::close()
{
int ret = ::close(m_fd);
m_fd = -1;
return ret;
}
ssize_t eRawFile::read(void *buf, size_t count)
{
// eDebug("read: %p, %d", buf, count);
switchOffset(m_current_offset);
if (m_nrfiles >= 2)
{
if (m_current_offset + count > m_totallength)
count = m_totallength - m_current_offset;
if (count < 0)
return 0;
}
int ret = ::read(m_fd, buf, count);
if (ret > 0)
m_current_offset = m_last_offset += ret;
return ret;
}
int eRawFile::valid()
{
return m_fd != -1;
}
void eRawFile::scan()
{
m_nrfiles = 0;
m_totallength = 0;
while (m_nrfiles < 1000) /* .999 is the last possible */
{
int f = openFile(m_nrfiles);
if (f < 0)
break;
if (!m_nrfiles)
m_splitsize = ::lseek(f, 0, SEEK_END);
m_totallength += ::lseek(f, 0, SEEK_END);
::close(f);
++m_nrfiles;
}
// eDebug("found %d files, splitsize: %llx, totallength: %llx", m_nrfiles, m_splitsize, m_totallength);
}
int eRawFile::switchOffset(off_t off)
{
if (m_splitsize)
{
int filenr = off / m_splitsize;
if (filenr >= m_nrfiles)
filenr = m_nrfiles - 1;
if (filenr != m_current_file)
{
// eDebug("-> %d", filenr);
close();
m_fd = openFile(filenr);
m_last_offset = m_base_offset = m_splitsize * filenr;
m_current_file = filenr;
}
} else
m_base_offset = 0;
if (off != m_last_offset)
{
// eDebug("%llx != %llx", off, m_last_offset);
m_last_offset = ::lseek(m_fd, off - m_base_offset, SEEK_SET) + m_base_offset;
// eDebug("offset now %llx", m_last_offset);
return m_last_offset;
} else
{
// eDebug("offset already ok");
return m_last_offset;
}
}
int eRawFile::openFile(int nr)
{
std::string filename = m_basename;
if (nr)
{
char suffix[5];
snprintf(suffix, 5, ".%03d", nr);
filename += suffix;
}
return ::open(filename.c_str(), O_RDONLY);
}
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