Amebis/stdex
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

stream: fix cache handling in open and close

Browse Source 
Reusing same class instance for different files reused cache content
as well.

Reported-by: Peter Holozan <peter.holozan@amebis.si>
Signed-off-by: Simon Rozman <simon@rozman.si>
This commit is contained in:
Simon Rozman
2023-08-21 10:27:43 +02:00
parent e7b6ab5345
commit 55d39b1566
2 changed files with 94 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files

73
include/stdex/stream.hpp
View File

@@ -1644,6 +1644,10 @@ namespace stdex
m_state = source.state();
m_source = &source;
m_offset = source.tell();
#if SET_FILE_OP_TIMES
m_atime = source.atime();
m_mtime = source.mtime();
#endif
}
public:
@@ -1653,15 +1657,17 @@ namespace stdex
m_cache(cache_size),
m_offset(source.tell())
#if SET_FILE_OP_TIMES
, m_atime(time_point::min()),
m_mtime(time_point::min())
, m_atime(source.atime()),
m_mtime(source.mtime())
#endif
{}
virtual ~cache()
virtual ~cache() noexcept(false)
{
if (m_source) {
flush_cache();
if (!ok()) _Unlikely_
throw std::runtime_error("cache flush failed"); // Data loss occured
m_source->seek(m_offset);
}
}
@@ -1726,7 +1732,7 @@ namespace stdex
return length - to_read;
}
}
}
}
virtual _Success_(return != 0) size_t write(
_In_reads_bytes_opt_(length) const void* data, _In_ size_t length)
@@ -1767,12 +1773,12 @@ namespace stdex
if (!ok()) _Unlikely_
return length - to_write;
size_t num_written = m_source->write(data, to_write - static_cast<size_t>(end_max % m_cache.capacity));
reinterpret_cast<const uint8_t*&>(data) += num_written;
to_write -= num_written;
m_offset += num_written;
m_state = m_source->state();
to_write -= num_written;
if (!to_write || !ok())
return length - to_write;
reinterpret_cast<const uint8_t*&>(data) += num_written;
}
}
load_cache(m_offset);
@@ -1783,7 +1789,9 @@ namespace stdex
virtual void close()
{
flush_cache();
invalidate_cache();
if (!ok()) _Unlikely_
throw std::runtime_error("cache flush failed"); // Data loss occured
m_source->close();
m_state = m_source->state();
}
@@ -1833,7 +1841,9 @@ namespace stdex
virtual fsize_t size()
{
return m_cache.data ? std::max(m_source->size(), m_cache.region.end) : m_source->size();
return m_cache.status != cache_t::cache_t::status_t::empty ?
std::max(m_source->size(), m_cache.region.end) :
m_source->size();
}
virtual void truncate()
@@ -1851,7 +1861,6 @@ namespace stdex
}
else {
// Truncation invalidates cache.
m_cache.region = 0;
m_cache.status = cache_t::cache_t::status_t::empty;
}
m_source->truncate();
@@ -1905,13 +1914,10 @@ namespace stdex
protected:
void flush_cache()
{
if (m_cache.status != cache_t::cache_t::status_t::dirty) {
if (m_cache.status != cache_t::cache_t::status_t::dirty)
m_state = state_t::ok;
}
else if (!m_cache.region.empty()) {
m_source->seek(m_cache.region.start);
m_source->write(m_cache.data, static_cast<size_t>(m_cache.region.size()));
m_state = m_source->state();
write_cache();
if (ok())
m_cache.status = cache_t::cache_t::status_t::loaded;
}
@@ -1923,11 +1929,13 @@ namespace stdex
void invalidate_cache()
{
flush_cache();
if (ok()) {
m_cache.region = 0;
m_cache.status = cache_t::cache_t::status_t::empty;
}
if (m_cache.status == cache_t::cache_t::status_t::dirty && !m_cache.region.empty()) {
write_cache();
if (!ok()) _Unlikely_
return;
} else
m_state = state_t::ok;
m_cache.status = cache_t::cache_t::status_t::empty;
}
void load_cache(_In_ fpos_t start)
@@ -1944,6 +1952,14 @@ namespace stdex
m_state = state_t::fail;
}
void write_cache()
{
assert(m_cache.status == cache_t::cache_t::status_t::dirty);
m_source->seek(m_cache.region.start);
m_source->write(m_cache.data, static_cast<size_t>(m_cache.region.size()));
m_state = m_source->state();
}
basic_file* m_source;
struct cache_t {
uint8_t* data;
@@ -1973,7 +1989,7 @@ namespace stdex
m_atime,
m_mtime;
#endif
};
};
///
/// OS data stream (file, pipe, socket...)
@@ -2675,7 +2691,7 @@ namespace stdex
///
cached_file(_In_z_ const sys_char* filename, _In_ int mode, _In_ size_t cache_size = default_cache_size) :
cache(cache_size),
m_source(filename, mode& mode_for_writing ? mode | mode_for_reading : mode)
m_source(filename, mode & mode_for_writing ? mode | mode_for_reading : mode)
{
init(m_source);
}
@@ -2689,18 +2705,23 @@ namespace stdex
///
void open(_In_z_ const sys_char* filename, _In_ int mode)
{
if (mode & mode_for_writing) mode |= mode_for_reading;
m_source.open(filename, mode);
invalidate_cache();
if (!ok()) _Unlikely_{
m_state = state_t::fail;
return;
}
m_source.open(filename, mode & mode_for_writing ? mode | mode_for_reading : mode);
if (m_source.ok()) {
#if SET_FILE_OP_TIMES
m_atime = m_mtime = time_point::min();
m_atime = m_source.atime();
m_mtime = m_source.mtime();
#endif
m_offset = m_source.tell();
m_state = state_t::ok;
return;
}
}
m_state = state_t::fail;
}
}
protected:
file m_source;