diff options
Diffstat (limited to 'classllfio__v2__xxx_1_1fast__random__file__handle.html')
| -rw-r--r-- | classllfio__v2__xxx_1_1fast__random__file__handle.html | 184 |
1 files changed, 87 insertions, 97 deletions
diff --git a/classllfio__v2__xxx_1_1fast__random__file__handle.html b/classllfio__v2__xxx_1_1fast__random__file__handle.html index ddcf3c7f..d563f904 100644 --- a/classllfio__v2__xxx_1_1fast__random__file__handle.html +++ b/classllfio__v2__xxx_1_1fast__random__file__handle.html @@ -167,29 +167,13 @@ template<class T > </td></tr> template<class T > </td></tr> <tr class="memitem:a386543b3dd65d4d416d755a153eef593"><td class="memTemplItemLeft" align="right" valign="top">using </td><td class="memTemplItemRight" valign="bottom"><b>io_result</b> = <a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__result.html">io_handle::io_result</a>< T ></td></tr> <tr class="separator:a386543b3dd65d4d416d755a153eef593"><td class="memSeparator" colspan="2"> </td></tr> -<tr class="memitem:a5929f46f42112bd805ab5001bfbf9d2a"><td class="memItemLeft" align="right" valign="top">enum  </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2a">bitfield__flag</a> : unsigned { <br /> -  <a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aae6fb35b3d125d5d76bbef95b1d804298">none</a> = 0, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa334c4a4c42fdb79d7ebc3e73b517e6f8">none</a> = 2, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa334c4a4c42fdb79d7ebc3e73b517e6f8">none</a> = 1, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa72328d49ab1e37950ff31891b47a6962">unlink_on_first_close</a> = 1U << 0U, -<br /> -  <a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aad624bee14c8a425153440c17bd2d893d">disable_safety_barriers</a> = 1U << 2U, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa5832b1ccb7f83ea61bf9e7f237ea481b">disable_safety_unlinks</a> = 1U << 3U, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa4557d4caa81561875089ae5f819fb2c3">disable_prefetching</a> = 1U << 4U, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aaf131856fed08b53ec642fbdc6d063de0">maximum_prefetching</a> = 1U << 5U, -<br /> -  <a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aacf17c790c4b3af070b11bc5b75911f9c">win_disable_unlink_emulation</a> = 1U << 24U, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aaafd26e37b4a783bd9814549fb4ff6cd0">win_disable_sparse_file_creation</a> = 1U << 25U, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa49d1f07791f8f6d711df222027abe322">disable_parallelism</a> = 1U << 26U, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa3375a48d9e197ee058d14e4df6c8b681">win_create_case_sensitive_directory</a> = 1U << 27U, -<br /> -  <a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aab099987c48559cca2de094c74ffc702a">overlapped</a> = 1U << 28U, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa6aa77c9bac6dd95b83f8d278f0e5fa59">byte_lock_insanity</a> = 1U << 29U, -<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa07122ea63cdc5b2c07e764d95a816d3d">anonymous_inode</a> = 1U << 30U -<br /> - }<tr class="memdesc:a5929f46f42112bd805ab5001bfbf9d2a"><td class="mdescLeft"> </td><td class="mdescRight">Bitwise flags which can be specified. <a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2a">More...</a><br /></td></tr> +<tr class="memitem:a7816bb7ae5156fa2997b68e6300ae565"><td class="memItemLeft" align="right" valign="top">enum  </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565">barrier_kind</a> { <a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565a2f6648dac37731813bb84ae9b24bdfdb">barrier_kind::nowait_data_only</a>, +<a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565af1d3baf03681db9a9986e0a76d6107ce">barrier_kind::wait_data_only</a>, +<a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565ab7a52d26120f585b21e8960812db5bf1">barrier_kind::nowait_all</a>, +<a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565a4e1789381cf8c976ec7a7118b3529345">barrier_kind::wait_all</a> + }<tr class="memdesc:a7816bb7ae5156fa2997b68e6300ae565"><td class="mdescLeft"> </td><td class="mdescRight">The kinds of write reordering barrier which can be performed. <a href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565">More...</a><br /></td></tr> </td></tr> -<tr class="separator:a5929f46f42112bd805ab5001bfbf9d2a"><td class="memSeparator" colspan="2"> </td></tr> +<tr class="separator:a7816bb7ae5156fa2997b68e6300ae565"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a1a65884346740af7fb4648c79d44a750"><td class="memItemLeft" align="right" valign="top"><a id="a1a65884346740af7fb4648c79d44a750"></a> using </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1fs__handle.html#a1a65884346740af7fb4648c79d44a750">unique_id_type</a> = QUICKCPPLIB_NAMESPACE::integers128::uint128</td></tr> <tr class="memdesc:a1a65884346740af7fb4648c79d44a750"><td class="mdescLeft"> </td><td class="mdescRight">The unique identifier type used by this handle. <br /></td></tr> @@ -251,9 +235,9 @@ virtual result< std::vector< std::pair< extent_type, extent_type > & <tr class="memitem:abdbe878fecb166d1eda5ddc4718e101d"><td class="memItemLeft" align="right" valign="top">virtual <a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__result.html">io_result</a>< const_buffers_type > </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1fast__random__file__handle.html#abdbe878fecb166d1eda5ddc4718e101d">write</a> (<a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__request.html">io_request</a>< const_buffers_type > reqs, <a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a> d=<a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a>()) noexcept override</td></tr> <tr class="memdesc:abdbe878fecb166d1eda5ddc4718e101d"><td class="mdescLeft"> </td><td class="mdescRight">Fails to write to the random file. <a href="#abdbe878fecb166d1eda5ddc4718e101d">More...</a><br /></td></tr> <tr class="separator:abdbe878fecb166d1eda5ddc4718e101d"><td class="memSeparator" colspan="2"> </td></tr> -<tr class="memitem:a97b9f47875b8ebc87965a8362d62b633"><td class="memItemLeft" align="right" valign="top"><a id="a97b9f47875b8ebc87965a8362d62b633"></a> -virtual <a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__result.html">io_result</a>< const_buffers_type > </td><td class="memItemRight" valign="bottom"><b>barrier</b> (<a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__request.html">io_request</a>< const_buffers_type > reqs=<a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__request.html">io_request</a>< const_buffers_type >(), bool=false, bool=false, <a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a>=<a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a>()) noexcept override</td></tr> -<tr class="separator:a97b9f47875b8ebc87965a8362d62b633"><td class="memSeparator" colspan="2"> </td></tr> +<tr class="memitem:a28f78f709ba3d7b26ba38cefa21fd7b8"><td class="memItemLeft" align="right" valign="top"><a id="a28f78f709ba3d7b26ba38cefa21fd7b8"></a> +virtual <a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__result.html">io_result</a>< const_buffers_type > </td><td class="memItemRight" valign="bottom"><b>barrier</b> (<a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__request.html">io_request</a>< const_buffers_type > reqs=<a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__request.html">io_request</a>< const_buffers_type >(), <a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565">barrier_kind</a>=<a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565a2f6648dac37731813bb84ae9b24bdfdb">barrier_kind::nowait_data_only</a>, <a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a>=<a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a>()) noexcept override</td></tr> +<tr class="separator:a28f78f709ba3d7b26ba38cefa21fd7b8"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a23d7f6342dead9266633176cd578714d"><td class="memItemLeft" align="right" valign="top">virtual result< <a class="el" href="classllfio__v2__xxx_1_1io__handle_1_1extent__guard.html">extent_guard</a> > </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1fast__random__file__handle.html#a23d7f6342dead9266633176cd578714d">lock</a> (extent_type offset, extent_type bytes, bool exclusive=true, <a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a>=<a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a>()) noexcept override</td></tr> <tr class="memdesc:a23d7f6342dead9266633176cd578714d"><td class="mdescLeft"> </td><td class="mdescRight">Tries to lock the range of bytes specified for shared or exclusive access. Be aware this passes through the same semantics as the underlying OS call, including any POSIX insanity present on your platform: <a href="#a23d7f6342dead9266633176cd578714d">More...</a><br /></td></tr> <tr class="separator:a23d7f6342dead9266633176cd578714d"><td class="memSeparator" colspan="2"> </td></tr> @@ -268,9 +252,9 @@ void </td><td class="memItemRight" valign="bottom"><a class="el" href="clas void </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1handle.html#a4716696b8700953889006251e0678aa4">swap</a> (<a class="el" href="classllfio__v2__xxx_1_1handle.html">handle</a> &o) noexcept</td></tr> <tr class="memdesc:a4716696b8700953889006251e0678aa4"><td class="mdescLeft"> </td><td class="mdescRight">Swap with another instance. <br /></td></tr> <tr class="separator:a4716696b8700953889006251e0678aa4"><td class="memSeparator" colspan="2"> </td></tr> -<tr class="memitem:aa3ec366f663f85fb4d679542b8c1b41a"><td class="memItemLeft" align="right" valign="top">virtual <a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__result.html">io_result</a>< const_buffers_type > </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1io__handle.html#aa3ec366f663f85fb4d679542b8c1b41a">barrier</a> (<a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__request.html">io_request</a>< const_buffers_type > reqs=<a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__request.html">io_request</a>< const_buffers_type >(), bool wait_for_device=false, bool and_metadata=false, <a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a> d=<a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a>()) noexcept=0</td></tr> -<tr class="memdesc:aa3ec366f663f85fb4d679542b8c1b41a"><td class="mdescLeft"> </td><td class="mdescRight">Issue a write reordering barrier such that writes preceding the barrier will reach storage before writes after this barrier. <a href="#aa3ec366f663f85fb4d679542b8c1b41a">More...</a><br /></td></tr> -<tr class="separator:aa3ec366f663f85fb4d679542b8c1b41a"><td class="memSeparator" colspan="2"> </td></tr> +<tr class="memitem:a823391cea8818da742c0d4c573f7300f"><td class="memItemLeft" align="right" valign="top">virtual <a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__result.html">io_result</a>< const_buffers_type > </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a823391cea8818da742c0d4c573f7300f">barrier</a> (<a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__request.html">io_request</a>< const_buffers_type > reqs=<a class="el" href="structllfio__v2__xxx_1_1io__handle_1_1io__request.html">io_request</a>< const_buffers_type >(), <a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565">barrier_kind</a> kind=<a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565a2f6648dac37731813bb84ae9b24bdfdb">barrier_kind::nowait_data_only</a>, <a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a> d=<a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a>()) noexcept=0</td></tr> +<tr class="memdesc:a823391cea8818da742c0d4c573f7300f"><td class="mdescLeft"> </td><td class="mdescRight">Issue a write reordering barrier such that writes preceding the barrier will reach storage before writes after this barrier. <a href="#a823391cea8818da742c0d4c573f7300f">More...</a><br /></td></tr> +<tr class="separator:a823391cea8818da742c0d4c573f7300f"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a6b97756d8d46e80da7d0fa04158a71a8"><td class="memItemLeft" align="right" valign="top">result< <a class="el" href="classllfio__v2__xxx_1_1file__handle.html">file_handle</a> > </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1file__handle.html#a6b97756d8d46e80da7d0fa04158a71a8">clone</a> (<a class="el" href="classllfio__v2__xxx_1_1handle.html#aa3930273a2d4cabbac309e0b75701dca">mode</a> mode_=mode::unchanged, <a class="el" href="classllfio__v2__xxx_1_1handle.html#aecd3a7db6cee3aec07d32fe6f99e6852">caching</a> caching_=caching::unchanged, <a class="el" href="structllfio__v2__xxx_1_1deadline.html">deadline</a> d=std::chrono::seconds(30)) const noexcept</td></tr> <tr class="separator:a6b97756d8d46e80da7d0fa04158a71a8"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:aeea4389189021b94dde6d8f2c3ccc5b3"><td class="memItemLeft" align="right" valign="top">result< <a class="el" href="classllfio__v2__xxx_1_1handle.html">handle</a> > </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1handle.html#aeea4389189021b94dde6d8f2c3ccc5b3">clone</a> () const noexcept</td></tr> @@ -300,6 +284,12 @@ void </td><td class="memItemRight" valign="bottom"><a class="el" href="clas <tr class="separator:a198e1c294966a28919d2f0698e3608b8"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:ae1abb705dbe9890e103365bf7c61521e"><td class="memItemLeft" align="right" valign="top">result< <a class="el" href="classllfio__v2__xxx_1_1io__handle_1_1extent__guard.html">extent_guard</a> > </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1io__handle.html#ae1abb705dbe9890e103365bf7c61521e">try_lock</a> (extent_type offset, extent_type bytes, bool exclusive=true) noexcept</td></tr> <tr class="separator:ae1abb705dbe9890e103365bf7c61521e"><td class="memSeparator" colspan="2"> </td></tr> +<tr class="memitem:ac5222904f116c9beb0515a4a5aa850bf"><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1handle.html#ac5222904f116c9beb0515a4a5aa850bf">QUICKCPPLIB_BITFIELD_BEGIN</a> (flag)</td></tr> +<tr class="memdesc:ac5222904f116c9beb0515a4a5aa850bf"><td class="mdescLeft"> </td><td class="mdescRight">Bitwise flags which can be specified. <a href="#ac5222904f116c9beb0515a4a5aa850bf">More...</a><br /></td></tr> +<tr class="separator:ac5222904f116c9beb0515a4a5aa850bf"><td class="memSeparator" colspan="2"> </td></tr> +<tr class="memitem:aa7e9bedf8c7a4c4a79a644a6e1857ee4"><td class="memItemLeft" align="right" valign="top"><a id="aa7e9bedf8c7a4c4a79a644a6e1857ee4"></a> + </td><td class="memItemRight" valign="bottom"><b>QUICKCPPLIB_BITFIELD_END</b> (flag)</td></tr> +<tr class="separator:aa7e9bedf8c7a4c4a79a644a6e1857ee4"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a00a85eec5a41f7edb2c574d40cf04535"><td class="memItemLeft" align="right" valign="top">virtual result< path_type > </td><td class="memItemRight" valign="bottom"><a class="el" href="classllfio__v2__xxx_1_1handle.html#a00a85eec5a41f7edb2c574d40cf04535">current_path</a> () const noexcept</td></tr> <tr class="separator:a00a85eec5a41f7edb2c574d40cf04535"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a1d273e38c061eb11f5012f624e9a202e"><td class="memItemLeft" align="right" valign="top"><a id="a1d273e38c061eb11f5012f624e9a202e"></a> @@ -438,7 +428,7 @@ extent_type </td><td class="memItemRight" valign="bottom"><b>_length</b> {0 <a class="el" href="classllfio__v2__xxx_1_1io__service.html">io_service</a> * </td><td class="memItemRight" valign="bottom"><b>_service</b> {nullptr}</td></tr> <tr class="separator:aa2c2b2847fd039b9c255633e6031817a"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:affb091ded80ffde7c0c3854e2abc52fd"><td class="memItemLeft" align="right" valign="top"><a id="affb091ded80ffde7c0c3854e2abc52fd"></a> -<a class="el" href="classllfio__v2__xxx_1_1handle.html#aecd3a7db6cee3aec07d32fe6f99e6852">caching</a> </td><td class="memItemRight" valign="bottom"><b>_caching</b> {<a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa334c4a4c42fdb79d7ebc3e73b517e6f8">caching::none</a>}</td></tr> +<a class="el" href="classllfio__v2__xxx_1_1handle.html#aecd3a7db6cee3aec07d32fe6f99e6852">caching</a> </td><td class="memItemRight" valign="bottom"><b>_caching</b> {<a class="el" href="classllfio__v2__xxx_1_1handle.html#aecd3a7db6cee3aec07d32fe6f99e6852a334c4a4c42fdb79d7ebc3e73b517e6f8">caching::none</a>}</td></tr> <tr class="separator:affb091ded80ffde7c0c3854e2abc52fd"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:ad758cf1eb2e0b4c63583eab05e7f6820"><td class="memItemLeft" align="right" valign="top"><a id="ad758cf1eb2e0b4c63583eab05e7f6820"></a> flag </td><td class="memItemRight" valign="bottom"><b>_flags</b> {flag::none}</td></tr> @@ -468,8 +458,8 @@ ino_t </td><td class="memItemRight" valign="bottom"><b>_inode</b> {0}</td>< <p>The current implementation spots when it can do 16x simultaneous PRNG rounds, and thus can fill a cache line at a time. The Skylake CPU used to benchmark the code dispatches around four times the throughput with this, however there is likely still performance left on the table.</p> <p>If someone were bothered to rewrite the JSF PRNG into SIMD, it is possible one could approach <code>memcpy()</code> in performance. One would probably need to use AVX-512 however, as the JSF PRNG makes heavy use of bit rotation, which is slow before AVX-512 as it must be emulated with copious bit shifting and masking. </p> </div><h2 class="groupheader">Member Enumeration Documentation</h2> -<a id="a5929f46f42112bd805ab5001bfbf9d2a"></a> -<h2 class="memtitle"><span class="permalink"><a href="#a5929f46f42112bd805ab5001bfbf9d2a">◆ </a></span>bitfield__flag</h2> +<a id="a7816bb7ae5156fa2997b68e6300ae565"></a> +<h2 class="memtitle"><span class="permalink"><a href="#a7816bb7ae5156fa2997b68e6300ae565">◆ </a></span>barrier_kind</h2> <div class="memitem"> <div class="memproto"> @@ -478,72 +468,33 @@ ino_t </td><td class="memItemRight" valign="bottom"><b>_inode</b> {0}</td>< <td class="mlabels-left"> <table class="memname"> <tr> - <td class="memname">enum <a class="el" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2a">llfio_v2_xxx::handle::bitfield__flag</a> : unsigned</td> + <td class="memname">enum <a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565">llfio_v2_xxx::io_handle::barrier_kind</a></td> </tr> </table> </td> <td class="mlabels-right"> -<span class="mlabels"><span class="mlabel">inherited</span></span> </td> +<span class="mlabels"><span class="mlabel">strong</span><span class="mlabel">inherited</span></span> </td> </tr> </table> </div><div class="memdoc"> -<p>Bitwise flags which can be specified. </p> +<p>The kinds of write reordering barrier which can be performed. </p> <table class="fieldtable"> -<tr><th colspan="2">Enumerator</th></tr><tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aae6fb35b3d125d5d76bbef95b1d804298"></a>none </td><td class="fielddoc"><p>No flags. </p> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aa334c4a4c42fdb79d7ebc3e73b517e6f8"></a>none </td><td class="fielddoc"><p>No ability to read or write anything, but can synchronise (SYNCHRONIZE or 0) </p> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aa334c4a4c42fdb79d7ebc3e73b517e6f8"></a>none </td><td class="fielddoc"><p>No caching whatsoever, all reads and writes come from storage (i.e. <code>O_DIRECT|O_SYNC</code>). Align all i/o to 4Kb boundaries for this to work. <code>disable_safety_barriers</code> can be used here. </p> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aa72328d49ab1e37950ff31891b47a6962"></a>unlink_on_first_close </td><td class="fielddoc"><p>Unlinks the file on handle close. On POSIX, this simply unlinks whatever is pointed to by <code>path()</code> upon the call of <code>close()</code> if and only if the inode matches. On Windows, if you are on Windows 10 1709 or later, exactly the same thing occurs. If on previous editions of Windows, the file entry does not disappears but becomes unavailable for anyone else to open with an <code>errc::resource_unavailable_try_again</code> error return. Because this is confusing, unless the <code>win_disable_unlink_emulation</code> flag is also specified, this POSIX behaviour is somewhat emulated by LLFIO on older Windows by renaming the file to a random name on <code>close()</code> causing it to appear to have been unlinked immediately. </p> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aad624bee14c8a425153440c17bd2d893d"></a>disable_safety_barriers </td><td class="fielddoc"><p>Some kernel caching modes have unhelpfully inconsistent behaviours in getting your data onto storage, so by default unless this flag is specified LLFIO adds extra fsyncs to the following operations for the caching modes specified below: truncation of file length either explicitly or during file open. closing of the handle either explicitly or in the destructor.</p> -<p>Additionally on Linux only to prevent loss of file metadata: On the parent directory whenever a file might have been created. On the parent directory on file close.</p> -<p>This only occurs for these kernel caching modes: caching::none caching::reads caching::reads_and_metadata caching::safety_barriers </p> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aa5832b1ccb7f83ea61bf9e7f237ea481b"></a>disable_safety_unlinks </td><td class="fielddoc"><p><code>file_handle::unlink()</code> could accidentally delete the wrong file if someone has renamed the open file handle since the time it was opened. To prevent this occuring, where the OS doesn't provide race free unlink-by-open-handle we compare the inode of the path we are about to unlink with that of the open handle before unlinking. </p><dl class="section warning"><dt>Warning</dt><dd>This does not prevent races where in between the time of checking the inode and executing the unlink a third party changes the item about to be unlinked. Only operating systems with a true race-free unlink syscall are race free. </dd></dl> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aa4557d4caa81561875089ae5f819fb2c3"></a>disable_prefetching </td><td class="fielddoc"><p>Ask the OS to disable prefetching of data. This can improve random i/o performance. </p> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aaf131856fed08b53ec642fbdc6d063de0"></a>maximum_prefetching </td><td class="fielddoc"><p>Ask the OS to maximise prefetching of data, possibly prefetching the entire file into kernel cache. This can improve sequential i/o performance. </p> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aacf17c790c4b3af070b11bc5b75911f9c"></a>win_disable_unlink_emulation </td><td class="fielddoc"><p>See the documentation for <code>unlink_on_first_close</code> </p> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aaafd26e37b4a783bd9814549fb4ff6cd0"></a>win_disable_sparse_file_creation </td><td class="fielddoc"><p>Microsoft Windows NTFS, having been created in the late 1980s, did not originally implement extents-based storage and thus could only represent sparse files via efficient compression of intermediate zeros. With NTFS v3.0 (Microsoft Windows 2000), a proper extents-based on-storage representation was added, thus allowing only 64Kb extent chunks written to be stored irrespective of whatever the maximum file extent was set to.</p> -<p>For various historical reasons, extents-based storage is disabled by default in newly created files on NTFS, unlike in almost every other major filing system. You have to explicitly "opt in" to extents-based storage.</p> -<p>As extents-based storage is nearly cost free on NTFS, LLFIO by default opts in to extents-based storage for any empty file it creates. If you don't want this, you can specify this flag to prevent that happening. </p> +<tr><th colspan="2">Enumerator</th></tr><tr><td class="fieldname"><a id="a7816bb7ae5156fa2997b68e6300ae565a2f6648dac37731813bb84ae9b24bdfdb"></a>nowait_data_only </td><td class="fielddoc"><p>Barrier data only, non-blocking. This is highly optimised on NV-DIMM storage, but consider using <code>nvram_barrier()</code> for even better performance. </p> </td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aa49d1f07791f8f6d711df222027abe322"></a>disable_parallelism </td><td class="fielddoc"><p>Filesystems tend to be embarrassingly parallel for operations performed to different inodes. Where LLFIO performs i/o to multiple inodes at a time, it will use OpenMP or the Parallelism or Concurrency standard library extensions to usually complete the operation in constant rather than linear time. If you don't want this default, you can disable default using this flag. </p> +<tr><td class="fieldname"><a id="a7816bb7ae5156fa2997b68e6300ae565af1d3baf03681db9a9986e0a76d6107ce"></a>wait_data_only </td><td class="fielddoc"><p>Barrier data only, block until it is done. This is highly optimised on NV-DIMM storage, but consider using <code>nvram_barrier()</code> for even better performance. </p> </td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aa3375a48d9e197ee058d14e4df6c8b681"></a>win_create_case_sensitive_directory </td><td class="fielddoc"><p>Microsoft Windows NTFS has the option, when creating a directory, to set whether leafname lookup will be case sensitive. This is the only way of getting exact POSIX semantics on Windows without resorting to editing the system registry, however it also affects all code doing lookups within that directory, so we must default it to off. </p> +<tr><td class="fieldname"><a id="a7816bb7ae5156fa2997b68e6300ae565ab7a52d26120f585b21e8960812db5bf1"></a>nowait_all </td><td class="fielddoc"><p>Barrier data and the metadata to retrieve it, non-blocking. </p> </td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aab099987c48559cca2de094c74ffc702a"></a>overlapped </td><td class="fielddoc"><p>On Windows, create any new handles with OVERLAPPED semantics. </p> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aa6aa77c9bac6dd95b83f8d278f0e5fa59"></a>byte_lock_insanity </td><td class="fielddoc"><p>Using insane POSIX byte range locks. </p> -</td></tr> -<tr><td class="fieldname"><a id="a5929f46f42112bd805ab5001bfbf9d2aa07122ea63cdc5b2c07e764d95a816d3d"></a>anonymous_inode </td><td class="fielddoc"><p>This is an inode created with no representation on the filing system. </p> +<tr><td class="fieldname"><a id="a7816bb7ae5156fa2997b68e6300ae565a4e1789381cf8c976ec7a7118b3529345"></a>wait_all </td><td class="fielddoc"><p>Barrier data and the metadata to retrieve it, block until it is done. </p> </td></tr> </table> -<div class="fragment"><div class="line"><a name="l00098"></a><span class="lineno"> 98</span>  {</div><div class="line"><a name="l00099"></a><span class="lineno"> 99</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aae6fb35b3d125d5d76bbef95b1d804298">none</a> = 0, <span class="comment">//!< No flags</span></div><div class="line"><a name="l00100"></a><span class="lineno"> 100</span> <span class="comment"></span><span class="comment"> /*! Unlinks the file on handle close. On POSIX, this simply unlinks whatever is pointed</span></div><div class="line"><a name="l00101"></a><span class="lineno"> 101</span> <span class="comment"> to by `path()` upon the call of `close()` if and only if the inode matches. On Windows,</span></div><div class="line"><a name="l00102"></a><span class="lineno"> 102</span> <span class="comment"> if you are on Windows 10 1709 or later, exactly the same thing occurs. If on previous</span></div><div class="line"><a name="l00103"></a><span class="lineno"> 103</span> <span class="comment"> editions of Windows, the file entry does not disappears but becomes unavailable for</span></div><div class="line"><a name="l00104"></a><span class="lineno"> 104</span> <span class="comment"> anyone else to open with an `errc::resource_unavailable_try_again` error return. Because this is confusing, unless the</span></div><div class="line"><a name="l00105"></a><span class="lineno"> 105</span> <span class="comment"> `win_disable_unlink_emulation` flag is also specified, this POSIX behaviour is</span></div><div class="line"><a name="l00106"></a><span class="lineno"> 106</span> <span class="comment"> somewhat emulated by LLFIO on older Windows by renaming the file to a random name on `close()`</span></div><div class="line"><a name="l00107"></a><span class="lineno"> 107</span> <span class="comment"> causing it to appear to have been unlinked immediately.</span></div><div class="line"><a name="l00108"></a><span class="lineno"> 108</span> <span class="comment"> */</span></div><div class="line"><a name="l00109"></a><span class="lineno"> 109</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa72328d49ab1e37950ff31891b47a6962">unlink_on_first_close</a> = 1U << 0U,</div><div class="line"><a name="l00110"></a><span class="lineno"> 110</span> <span class="comment"></span></div><div class="line"><a name="l00111"></a><span class="lineno"> 111</span> <span class="comment"> /*! Some kernel caching modes have unhelpfully inconsistent behaviours</span></div><div class="line"><a name="l00112"></a><span class="lineno"> 112</span> <span class="comment"> in getting your data onto storage, so by default unless this flag is</span></div><div class="line"><a name="l00113"></a><span class="lineno"> 113</span> <span class="comment"> specified LLFIO adds extra fsyncs to the following operations for the</span></div><div class="line"><a name="l00114"></a><span class="lineno"> 114</span> <span class="comment"> caching modes specified below:</span></div><div class="line"><a name="l00115"></a><span class="lineno"> 115</span> <span class="comment"> * truncation of file length either explicitly or during file open.</span></div><div class="line"><a name="l00116"></a><span class="lineno"> 116</span> <span class="comment"> * closing of the handle either explicitly or in the destructor.</span></div><div class="line"><a name="l00117"></a><span class="lineno"> 117</span> <span class="comment"></span></div><div class="line"><a name="l00118"></a><span class="lineno"> 118</span> <span class="comment"> Additionally on Linux only to prevent loss of file metadata:</span></div><div class="line"><a name="l00119"></a><span class="lineno"> 119</span> <span class="comment"> * On the parent directory whenever a file might have been created.</span></div><div class="line"><a name="l00120"></a><span class="lineno"> 120</span> <span class="comment"> * On the parent directory on file close.</span></div><div class="line"><a name="l00121"></a><span class="lineno"> 121</span> <span class="comment"></span></div><div class="line"><a name="l00122"></a><span class="lineno"> 122</span> <span class="comment"> This only occurs for these kernel caching modes:</span></div><div class="line"><a name="l00123"></a><span class="lineno"> 123</span> <span class="comment"> * caching::none</span></div><div class="line"><a name="l00124"></a><span class="lineno"> 124</span> <span class="comment"> * caching::reads</span></div><div class="line"><a name="l00125"></a><span class="lineno"> 125</span> <span class="comment"> * caching::reads_and_metadata</span></div><div class="line"><a name="l00126"></a><span class="lineno"> 126</span> <span class="comment"> * caching::safety_barriers</span></div><div class="line"><a name="l00127"></a><span class="lineno"> 127</span> <span class="comment"> */</span></div><div class="line"><a name="l00128"></a><span class="lineno"> 128</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aad624bee14c8a425153440c17bd2d893d">disable_safety_barriers</a> = 1U << 2U,<span class="comment"></span></div><div class="line"><a name="l00129"></a><span class="lineno"> 129</span> <span class="comment"> /*! `file_handle::unlink()` could accidentally delete the wrong file if someone has</span></div><div class="line"><a name="l00130"></a><span class="lineno"> 130</span> <span class="comment"> renamed the open file handle since the time it was opened. To prevent this occuring,</span></div><div class="line"><a name="l00131"></a><span class="lineno"> 131</span> <span class="comment"> where the OS doesn't provide race free unlink-by-open-handle we compare the inode of</span></div><div class="line"><a name="l00132"></a><span class="lineno"> 132</span> <span class="comment"> the path we are about to unlink with that of the open handle before unlinking.</span></div><div class="line"><a name="l00133"></a><span class="lineno"> 133</span> <span class="comment"> \warning This does not prevent races where in between the time of checking the inode</span></div><div class="line"><a name="l00134"></a><span class="lineno"> 134</span> <span class="comment"> and executing the unlink a third party changes the item about to be unlinked. Only</span></div><div class="line"><a name="l00135"></a><span class="lineno"> 135</span> <span class="comment"> operating systems with a true race-free unlink syscall are race free.</span></div><div class="line"><a name="l00136"></a><span class="lineno"> 136</span> <span class="comment"> */</span></div><div class="line"><a name="l00137"></a><span class="lineno"> 137</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa5832b1ccb7f83ea61bf9e7f237ea481b">disable_safety_unlinks</a> = 1U << 3U,<span class="comment"></span></div><div class="line"><a name="l00138"></a><span class="lineno"> 138</span> <span class="comment"> /*! Ask the OS to disable prefetching of data. This can improve random</span></div><div class="line"><a name="l00139"></a><span class="lineno"> 139</span> <span class="comment"> i/o performance.</span></div><div class="line"><a name="l00140"></a><span class="lineno"> 140</span> <span class="comment"> */</span></div><div class="line"><a name="l00141"></a><span class="lineno"> 141</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa4557d4caa81561875089ae5f819fb2c3">disable_prefetching</a> = 1U << 4U,<span class="comment"></span></div><div class="line"><a name="l00142"></a><span class="lineno"> 142</span> <span class="comment"> /*! Ask the OS to maximise prefetching of data, possibly prefetching the entire file</span></div><div class="line"><a name="l00143"></a><span class="lineno"> 143</span> <span class="comment"> into kernel cache. This can improve sequential i/o performance.</span></div><div class="line"><a name="l00144"></a><span class="lineno"> 144</span> <span class="comment"> */</span></div><div class="line"><a name="l00145"></a><span class="lineno"> 145</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aaf131856fed08b53ec642fbdc6d063de0">maximum_prefetching</a> = 1U << 5U,</div><div class="line"><a name="l00146"></a><span class="lineno"> 146</span> </div><div class="line"><a name="l00147"></a><span class="lineno"> 147</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aacf17c790c4b3af070b11bc5b75911f9c">win_disable_unlink_emulation</a> = 1U << 24U, <span class="comment">//!< See the documentation for `unlink_on_first_close`</span></div><div class="line"><a name="l00148"></a><span class="lineno"> 148</span> <span class="comment"></span><span class="comment"> /*! Microsoft Windows NTFS, having been created in the late 1980s, did not originally</span></div><div class="line"><a name="l00149"></a><span class="lineno"> 149</span> <span class="comment"> implement extents-based storage and thus could only represent sparse files via</span></div><div class="line"><a name="l00150"></a><span class="lineno"> 150</span> <span class="comment"> efficient compression of intermediate zeros. With NTFS v3.0 (Microsoft Windows 2000),</span></div><div class="line"><a name="l00151"></a><span class="lineno"> 151</span> <span class="comment"> a proper extents-based on-storage representation was added, thus allowing only 64Kb</span></div><div class="line"><a name="l00152"></a><span class="lineno"> 152</span> <span class="comment"> extent chunks written to be stored irrespective of whatever the maximum file extent</span></div><div class="line"><a name="l00153"></a><span class="lineno"> 153</span> <span class="comment"> was set to.</span></div><div class="line"><a name="l00154"></a><span class="lineno"> 154</span> <span class="comment"></span></div><div class="line"><a name="l00155"></a><span class="lineno"> 155</span> <span class="comment"> For various historical reasons, extents-based storage is disabled by default in newly</span></div><div class="line"><a name="l00156"></a><span class="lineno"> 156</span> <span class="comment"> created files on NTFS, unlike in almost every other major filing system. You have to</span></div><div class="line"><a name="l00157"></a><span class="lineno"> 157</span> <span class="comment"> explicitly "opt in" to extents-based storage.</span></div><div class="line"><a name="l00158"></a><span class="lineno"> 158</span> <span class="comment"></span></div><div class="line"><a name="l00159"></a><span class="lineno"> 159</span> <span class="comment"> As extents-based storage is nearly cost free on NTFS, LLFIO by default opts in to</span></div><div class="line"><a name="l00160"></a><span class="lineno"> 160</span> <span class="comment"> extents-based storage for any empty file it creates. If you don't want this, you</span></div><div class="line"><a name="l00161"></a><span class="lineno"> 161</span> <span class="comment"> can specify this flag to prevent that happening.</span></div><div class="line"><a name="l00162"></a><span class="lineno"> 162</span> <span class="comment"> */</span></div><div class="line"><a name="l00163"></a><span class="lineno"> 163</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aaafd26e37b4a783bd9814549fb4ff6cd0">win_disable_sparse_file_creation</a> = 1U << 25U,<span class="comment"></span></div><div class="line"><a name="l00164"></a><span class="lineno"> 164</span> <span class="comment"> /*! Filesystems tend to be embarrassingly parallel for operations performed to different</span></div><div class="line"><a name="l00165"></a><span class="lineno"> 165</span> <span class="comment"> inodes. Where LLFIO performs i/o to multiple inodes at a time, it will use OpenMP or</span></div><div class="line"><a name="l00166"></a><span class="lineno"> 166</span> <span class="comment"> the Parallelism or Concurrency standard library extensions to usually complete the</span></div><div class="line"><a name="l00167"></a><span class="lineno"> 167</span> <span class="comment"> operation in constant rather than linear time. If you don't want this default, you can</span></div><div class="line"><a name="l00168"></a><span class="lineno"> 168</span> <span class="comment"> disable default using this flag.</span></div><div class="line"><a name="l00169"></a><span class="lineno"> 169</span> <span class="comment"> */</span></div><div class="line"><a name="l00170"></a><span class="lineno"> 170</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa49d1f07791f8f6d711df222027abe322">disable_parallelism</a> = 1U << 26U,<span class="comment"></span></div><div class="line"><a name="l00171"></a><span class="lineno"> 171</span> <span class="comment"> /*! Microsoft Windows NTFS has the option, when creating a directory, to set whether</span></div><div class="line"><a name="l00172"></a><span class="lineno"> 172</span> <span class="comment"> leafname lookup will be case sensitive. This is the only way of getting exact POSIX</span></div><div class="line"><a name="l00173"></a><span class="lineno"> 173</span> <span class="comment"> semantics on Windows without resorting to editing the system registry, however it also</span></div><div class="line"><a name="l00174"></a><span class="lineno"> 174</span> <span class="comment"> affects all code doing lookups within that directory, so we must default it to off.</span></div><div class="line"><a name="l00175"></a><span class="lineno"> 175</span> <span class="comment"> */</span></div><div class="line"><a name="l00176"></a><span class="lineno"> 176</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa3375a48d9e197ee058d14e4df6c8b681">win_create_case_sensitive_directory</a> = 1U << 27U,</div><div class="line"><a name="l00177"></a><span class="lineno"> 177</span> </div><div class="line"><a name="l00178"></a><span class="lineno"> 178</span>  <span class="comment">// NOTE: IF UPDATING THIS UPDATE THE std::ostream PRINTER BELOW!!!</span></div><div class="line"><a name="l00179"></a><span class="lineno"> 179</span> </div><div class="line"><a name="l00180"></a><span class="lineno"> 180</span>  <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aab099987c48559cca2de094c74ffc702a">overlapped</a> = 1U << 28U, <span class="comment">//!< On Windows, create any new handles with OVERLAPPED semantics</span></div><div class="line"><a name="l00181"></a><span class="lineno"> 181</span> <span class="comment"></span> <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa6aa77c9bac6dd95b83f8d278f0e5fa59">byte_lock_insanity</a> = 1U << 29U, <span class="comment">//!< Using insane POSIX byte range locks</span></div><div class="line"><a name="l00182"></a><span class="lineno"> 182</span> <span class="comment"></span> <a class="code" href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa07122ea63cdc5b2c07e764d95a816d3d">anonymous_inode</a> = 1U << 30U <span class="comment">//!< This is an inode created with no representation on the filing system</span></div><div class="line"><a name="l00183"></a><span class="lineno"> 183</span> <span class="comment"></span> } QUICKCPPLIB_BITFIELD_END(flag);</div><div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aa3375a48d9e197ee058d14e4df6c8b681"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa3375a48d9e197ee058d14e4df6c8b681">llfio_v2_xxx::handle::win_create_case_sensitive_directory</a></div><div class="ttdef"><b>Definition:</b> handle.hpp:176</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aa07122ea63cdc5b2c07e764d95a816d3d"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa07122ea63cdc5b2c07e764d95a816d3d">llfio_v2_xxx::handle::anonymous_inode</a></div><div class="ttdoc">This is an inode created with no representation on the filing system. </div><div class="ttdef"><b>Definition:</b> handle.hpp:182</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aa5832b1ccb7f83ea61bf9e7f237ea481b"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa5832b1ccb7f83ea61bf9e7f237ea481b">llfio_v2_xxx::handle::disable_safety_unlinks</a></div><div class="ttdef"><b>Definition:</b> handle.hpp:137</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aa49d1f07791f8f6d711df222027abe322"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa49d1f07791f8f6d711df222027abe322">llfio_v2_xxx::handle::disable_parallelism</a></div><div class="ttdef"><b>Definition:</b> handle.hpp:170</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aae6fb35b3d125d5d76bbef95b1d804298"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aae6fb35b3d125d5d76bbef95b1d804298">llfio_v2_xxx::handle::none</a></div><div class="ttdoc">No flags. </div><div class="ttdef"><b>Definition:</b> handle.hpp:99</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aaf131856fed08b53ec642fbdc6d063de0"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aaf131856fed08b53ec642fbdc6d063de0">llfio_v2_xxx::handle::maximum_prefetching</a></div><div class="ttdef"><b>Definition:</b> handle.hpp:145</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aab099987c48559cca2de094c74ffc702a"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aab099987c48559cca2de094c74ffc702a">llfio_v2_xxx::handle::overlapped</a></div><div class="ttdoc">On Windows, create any new handles with OVERLAPPED semantics. </div><div class="ttdef"><b>Definition:</b> handle.hpp:180</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aa4557d4caa81561875089ae5f819fb2c3"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa4557d4caa81561875089ae5f819fb2c3">llfio_v2_xxx::handle::disable_prefetching</a></div><div class="ttdef"><b>Definition:</b> handle.hpp:141</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aa6aa77c9bac6dd95b83f8d278f0e5fa59"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa6aa77c9bac6dd95b83f8d278f0e5fa59">llfio_v2_xxx::handle::byte_lock_insanity</a></div><div class="ttdoc">Using insane POSIX byte range locks. </div><div class="ttdef"><b>Definition:</b> handle.hpp:181</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aa72328d49ab1e37950ff31891b47a6962"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aa72328d49ab1e37950ff31891b47a6962">llfio_v2_xxx::handle::unlink_on_first_close</a></div><div class="ttdef"><b>Definition:</b> handle.hpp:109</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aacf17c790c4b3af070b11bc5b75911f9c"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aacf17c790c4b3af070b11bc5b75911f9c">llfio_v2_xxx::handle::win_disable_unlink_emulation</a></div><div class="ttdoc">See the documentation for unlink_on_first_close </div><div class="ttdef"><b>Definition:</b> handle.hpp:147</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aad624bee14c8a425153440c17bd2d893d"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aad624bee14c8a425153440c17bd2d893d">llfio_v2_xxx::handle::disable_safety_barriers</a></div><div class="ttdef"><b>Definition:</b> handle.hpp:128</div></div> -<div class="ttc" id="classllfio__v2__xxx_1_1handle_html_a5929f46f42112bd805ab5001bfbf9d2aaafd26e37b4a783bd9814549fb4ff6cd0"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#a5929f46f42112bd805ab5001bfbf9d2aaafd26e37b4a783bd9814549fb4ff6cd0">llfio_v2_xxx::handle::win_disable_sparse_file_creation</a></div><div class="ttdef"><b>Definition:</b> handle.hpp:163</div></div> -</div><!-- fragment --> +<div class="fragment"><div class="line"><a name="l00055"></a><span class="lineno"> 55</span>  {</div><div class="line"><a name="l00056"></a><span class="lineno"> 56</span>  nowait_data_only, <span class="comment">//!< Barrier data only, non-blocking. This is highly optimised on NV-DIMM storage, but consider using `nvram_barrier()` for even better performance.</span></div><div class="line"><a name="l00057"></a><span class="lineno"> 57</span> <span class="comment"></span> wait_data_only, <span class="comment">//!< Barrier data only, block until it is done. This is highly optimised on NV-DIMM storage, but consider using `nvram_barrier()` for even better performance.</span></div><div class="line"><a name="l00058"></a><span class="lineno"> 58</span> <span class="comment"></span> nowait_all, <span class="comment">//!< Barrier data and the metadata to retrieve it, non-blocking.</span></div><div class="line"><a name="l00059"></a><span class="lineno"> 59</span> <span class="comment"></span> wait_all <span class="comment">//!< Barrier data and the metadata to retrieve it, block until it is done.</span></div><div class="line"><a name="l00060"></a><span class="lineno"> 60</span> <span class="comment"></span> };</div></div><!-- fragment --> </div> </div> <h2 class="groupheader">Member Function Documentation</h2> -<a id="aa3ec366f663f85fb4d679542b8c1b41a"></a> -<h2 class="memtitle"><span class="permalink"><a href="#aa3ec366f663f85fb4d679542b8c1b41a">◆ </a></span>barrier()</h2> +<a id="a823391cea8818da742c0d4c573f7300f"></a> +<h2 class="memtitle"><span class="permalink"><a href="#a823391cea8818da742c0d4c573f7300f">◆ </a></span>barrier()</h2> <div class="memitem"> <div class="memproto"> @@ -560,14 +511,8 @@ ino_t </td><td class="memItemRight" valign="bottom"><b>_inode</b> {0}</td>< <tr> <td class="paramkey"></td> <td></td> - <td class="paramtype">bool </td> - <td class="paramname"><em>wait_for_device</em> = <code>false</code>, </td> - </tr> - <tr> - <td class="paramkey"></td> - <td></td> - <td class="paramtype">bool </td> - <td class="paramname"><em>and_metadata</em> = <code>false</code>, </td> + <td class="paramtype"><a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565">barrier_kind</a> </td> + <td class="paramname"><em>kind</em> = <code><a class="el" href="classllfio__v2__xxx_1_1io__handle.html#a7816bb7ae5156fa2997b68e6300ae565a2f6648dac37731813bb84ae9b24bdfdb">barrier_kind::nowait_data_only</a></code>, </td> </tr> <tr> <td class="paramkey"></td> @@ -598,8 +543,7 @@ For portability, you can only assume that barriers write order for a single hand <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramname">reqs</td><td>A scatter-gather and offset request for what range to barrier. May be ignored on some platforms which always write barrier the entire file. Supplying a default initialised reqs write barriers the entire file. </td></tr> - <tr><td class="paramname">wait_for_device</td><td>True if you want the call to wait until data reaches storage and that storage has acknowledged the data is physically written. Slow. </td></tr> - <tr><td class="paramname">and_metadata</td><td>True if you want the call to sync the metadata for retrieving the writes before the barrier after a sudden power loss event. Slow. Setting this to false enables much faster performance, especially on non-volatile memory. </td></tr> + <tr><td class="paramname">kind</td><td>Which kind of write reordering barrier to perform. </td></tr> <tr><td class="paramname">d</td><td>An optional deadline by which the i/o must complete, else it is cancelled. Note function may return significantly after this deadline if the i/o takes long to cancel. </td></tr> </table> </dd> @@ -705,7 +649,7 @@ For portability, you can only assume that barriers write order for a single hand </table> </div><div class="memdoc"> <p>Returns the current path of the open handle as said by the operating system. Note that you are NOT guaranteed that any path refreshed bears any resemblance to the original, some operating systems will return some different path which still reaches the same inode via some other route e.g. hardlinks, dereferenced symbolic links, etc. Windows and Linux correctly track changes to the specific path the handle was opened with, not getting confused by other hard links. MacOS nearly gets it right, but under some circumstances e.g. renaming may switch to a different hard link's path which is almost certainly a bug.</p> -<p>If LLFIO was not able to determine the current path for this open handle e.g. the inode has been unlinked, it returns an empty path. Be aware that FreeBSD can return an empty (deleted) path for file inodes no longer cached by the kernel path cache, LLFIO cannot detect the difference. FreeBSD will also return any path leading to the inode if it is hard linked. FreeBSD does implement path retrieval for directory inodes correctly however, and see <code>algorithm::stablized_path<T></code> for a handle adapter which makes use of that.</p> +<p>If LLFIO was not able to determine the current path for this open handle e.g. the inode has been unlinked, it returns an empty path. Be aware that FreeBSD can return an empty (deleted) path for file inodes no longer cached by the kernel path cache, LLFIO cannot detect the difference. FreeBSD will also return any path leading to the inode if it is hard linked. FreeBSD does implement path retrieval for directory inodes correctly however, and see <code>algorithm::cached_parent_handle_adapter<T></code> for a handle adapter which makes use of that.</p> <p>On Linux if <code>/proc</code> is not mounted, this call fails with an error. All APIs in LLFIO which require the use of <code>current_path()</code> can be told to not use it e.g. <code>flag::disable_safety_unlinks</code>. It is up to you to detect if <code>current_path()</code> is not working, and to change how you call LLFIO appropriately.</p> <dl class="section warning"><dt>Warning</dt><dd>This call is expensive, it always asks the kernel for the current path, and no checking is done to ensure what the kernel returns is accurate or even sensible. Be aware that despite these precautions, paths are unstable and <b>can change randomly at any moment</b>. Most code written to use absolute file systems paths is <b>racy</b>, so don't do it, use <code>path_handle</code> to fix a base location on the file system and work from that anchor instead!</dd></dl> <dl class="section user"><dt>Memory Allocations</dt><dd>At least one malloc for the <code>path_type</code>, likely several more. </dd></dl> @@ -764,7 +708,7 @@ For portability, you can only assume that barriers write order for a single hand </dl> <div class="fragment"><div class="line"><a name="l00173"></a><span class="lineno"> 173</span>  {}) noexcept</div><div class="line"><a name="l00174"></a><span class="lineno"> 174</span>  {</div><div class="line"><a name="l00175"></a><span class="lineno"> 175</span>  <span class="keywordflow">if</span>(_mode == <a class="code" href="classllfio__v2__xxx_1_1handle.html#aa3930273a2d4cabbac309e0b75701dcaa9516dfb15f51c7ee19a4d46b8c0dbe1d">mode::append</a>)</div><div class="line"><a name="l00176"></a><span class="lineno"> 176</span>  {</div><div class="line"><a name="l00177"></a><span class="lineno"> 177</span>  <span class="keywordflow">return</span> errc::invalid_argument;</div><div class="line"><a name="l00178"></a><span class="lineno"> 178</span>  }</div><div class="line"><a name="l00179"></a><span class="lineno"> 179</span>  byte _seed[16];</div><div class="line"><a name="l00180"></a><span class="lineno"> 180</span>  <span class="keywordflow">if</span>(seed.empty())</div><div class="line"><a name="l00181"></a><span class="lineno"> 181</span>  {</div><div class="line"><a name="l00182"></a><span class="lineno"> 182</span>  <a class="code" href="namespacellfio__v2__xxx_1_1utils.html#ae61e2de30b06776a1c24643a1d1dc64e">utils::random_fill</a>((<span class="keywordtype">char</span> *) _seed, <span class="keyword">sizeof</span>(_seed));</div><div class="line"><a name="l00183"></a><span class="lineno"> 183</span>  seed = _seed;</div><div class="line"><a name="l00184"></a><span class="lineno"> 184</span>  }</div><div class="line"><a name="l00185"></a><span class="lineno"> 185</span>  result<fast_random_file_handle> ret(<a class="code" href="classllfio__v2__xxx_1_1fast__random__file__handle.html#a4661a9c1551d33d054ccd80599806ba7">fast_random_file_handle</a>(bytes, seed));</div><div class="line"><a name="l00186"></a><span class="lineno"> 186</span>  native_handle_type &nativeh = ret.value()._v;</div><div class="line"><a name="l00187"></a><span class="lineno"> 187</span>  LLFIO_LOG_FUNCTION_CALL(&ret);</div><div class="line"><a name="l00188"></a><span class="lineno"> 188</span>  nativeh.behaviour |= <a class="code" href="namespacellfio__v2__xxx.html#af31a062639499a79ef5cc8aed16ba65d">native_handle_type::disposition::file</a>;</div><div class="line"><a name="l00189"></a><span class="lineno"> 189</span>  nativeh.behaviour |= native_handle_type::disposition::seekable | native_handle_type::disposition::readable;</div><div class="line"><a name="l00190"></a><span class="lineno"> 190</span>  <span class="keywordflow">if</span>(_mode == <a class="code" href="classllfio__v2__xxx_1_1handle.html#aa3930273a2d4cabbac309e0b75701dcaaefb2a684e4afb7d55e6147fbe5a332ee">mode::write</a>)</div><div class="line"><a name="l00191"></a><span class="lineno"> 191</span>  {</div><div class="line"><a name="l00192"></a><span class="lineno"> 192</span>  nativeh.behaviour |= native_handle_type::disposition::writable;</div><div class="line"><a name="l00193"></a><span class="lineno"> 193</span>  }</div><div class="line"><a name="l00194"></a><span class="lineno"> 194</span>  <span class="keywordflow">return</span> ret;</div><div class="line"><a name="l00195"></a><span class="lineno"> 195</span>  }</div><div class="ttc" id="classllfio__v2__xxx_1_1fast__random__file__handle_html_a4661a9c1551d33d054ccd80599806ba7"><div class="ttname"><a href="classllfio__v2__xxx_1_1fast__random__file__handle.html#a4661a9c1551d33d054ccd80599806ba7">llfio_v2_xxx::fast_random_file_handle::fast_random_file_handle</a></div><div class="ttdeci">fast_random_file_handle()=default</div><div class="ttdoc">Default constructor. </div></div> <div class="ttc" id="classllfio__v2__xxx_1_1handle_html_aa3930273a2d4cabbac309e0b75701dcaaefb2a684e4afb7d55e6147fbe5a332ee"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#aa3930273a2d4cabbac309e0b75701dcaaefb2a684e4afb7d55e6147fbe5a332ee">llfio_v2_xxx::handle::mode::write</a></div><div class="ttdoc">Ability to read and write (READ_CONTROL|FILE_READ_DATA|FILE_READ_ATTRIBUTES|FILE_READ_EA|FILE_WRITE_D...</div></div> -<div class="ttc" id="namespacellfio__v2__xxx_html_af31a062639499a79ef5cc8aed16ba65d"><div class="ttname"><a href="namespacellfio__v2__xxx.html#af31a062639499a79ef5cc8aed16ba65d">llfio_v2_xxx::file</a></div><div class="ttdeci">result< file_handle > file(const path_handle &base, file_handle::path_view_type path, file_handle::mode _mode=file_handle::mode::read, file_handle::creation _creation=file_handle::creation::open_existing, file_handle::caching _caching=file_handle::caching::all, file_handle::flag flags=file_handle::flag::none) noexcept</div><div class="ttdef"><b>Definition:</b> file_handle.hpp:334</div></div> +<div class="ttc" id="namespacellfio__v2__xxx_html_af31a062639499a79ef5cc8aed16ba65d"><div class="ttname"><a href="namespacellfio__v2__xxx.html#af31a062639499a79ef5cc8aed16ba65d">llfio_v2_xxx::file</a></div><div class="ttdeci">result< file_handle > file(const path_handle &base, file_handle::path_view_type path, file_handle::mode _mode=file_handle::mode::read, file_handle::creation _creation=file_handle::creation::open_existing, file_handle::caching _caching=file_handle::caching::all, file_handle::flag flags=file_handle::flag::none) noexcept</div><div class="ttdef"><b>Definition:</b> file_handle.hpp:335</div></div> <div class="ttc" id="namespacellfio__v2__xxx_1_1utils_html_ae61e2de30b06776a1c24643a1d1dc64e"><div class="ttname"><a href="namespacellfio__v2__xxx_1_1utils.html#ae61e2de30b06776a1c24643a1d1dc64e">llfio_v2_xxx::utils::random_fill</a></div><div class="ttdeci">void random_fill(char *buffer, size_t bytes) noexcept</div><div class="ttdoc">Fills the buffer supplied with cryptographically strong randomness. Uses the OS kernel API...</div></div> <div class="ttc" id="classllfio__v2__xxx_1_1handle_html_aa3930273a2d4cabbac309e0b75701dcaa9516dfb15f51c7ee19a4d46b8c0dbe1d"><div class="ttname"><a href="classllfio__v2__xxx_1_1handle.html#aa3930273a2d4cabbac309e0b75701dcaa9516dfb15f51c7ee19a4d46b8c0dbe1d">llfio_v2_xxx::handle::mode::append</a></div><div class="ttdoc">All mainstream OSs and CIFS guarantee this is atomic with respect to all other appenders (FILE_APPEND...</div></div> </div><!-- fragment --> @@ -946,7 +890,7 @@ For portability, you can only assume that barriers write order for a single hand </table> </div><div class="memdoc"> <p>This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. </p> -<div class="fragment"><div class="line"><a name="l00503"></a><span class="lineno"> 503</span>  {</div><div class="line"><a name="l00504"></a><span class="lineno"> 504</span>  <span class="keywordtype">size_t</span> bytes = 0;</div><div class="line"><a name="l00505"></a><span class="lineno"> 505</span>  <span class="keywordflow">for</span>(<span class="keyword">auto</span> &i : reqs.buffers)</div><div class="line"><a name="l00506"></a><span class="lineno"> 506</span>  {</div><div class="line"><a name="l00507"></a><span class="lineno"> 507</span>  <span class="keywordflow">if</span>(bytes + i.size() < bytes)</div><div class="line"><a name="l00508"></a><span class="lineno"> 508</span>  {</div><div class="line"><a name="l00509"></a><span class="lineno"> 509</span>  <span class="keywordflow">return</span> errc::value_too_large;</div><div class="line"><a name="l00510"></a><span class="lineno"> 510</span>  }</div><div class="line"><a name="l00511"></a><span class="lineno"> 511</span>  bytes += i.size();</div><div class="line"><a name="l00512"></a><span class="lineno"> 512</span>  }</div><div class="line"><a name="l00513"></a><span class="lineno"> 513</span>  <span class="keywordflow">return</span> <a class="code" href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">lock</a>(reqs.offset, bytes, <span class="keyword">false</span>, d);</div><div class="line"><a name="l00514"></a><span class="lineno"> 514</span>  }</div><div class="ttc" id="classllfio__v2__xxx_1_1io__handle_html_a29cc9f2525f78dd73f8402cb59d97212"><div class="ttname"><a href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">llfio_v2_xxx::io_handle::lock</a></div><div class="ttdeci">virtual result< extent_guard > lock(extent_type offset, extent_type bytes, bool exclusive=true, deadline d=deadline()) noexcept</div><div class="ttdoc">Tries to lock the range of bytes specified for shared or exclusive access. Be aware this passes throu...</div></div> +<div class="fragment"><div class="line"><a name="l00538"></a><span class="lineno"> 538</span>  {</div><div class="line"><a name="l00539"></a><span class="lineno"> 539</span>  <span class="keywordtype">size_t</span> bytes = 0;</div><div class="line"><a name="l00540"></a><span class="lineno"> 540</span>  <span class="keywordflow">for</span>(<span class="keyword">auto</span> &i : reqs.buffers)</div><div class="line"><a name="l00541"></a><span class="lineno"> 541</span>  {</div><div class="line"><a name="l00542"></a><span class="lineno"> 542</span>  <span class="keywordflow">if</span>(bytes + i.size() < bytes)</div><div class="line"><a name="l00543"></a><span class="lineno"> 543</span>  {</div><div class="line"><a name="l00544"></a><span class="lineno"> 544</span>  <span class="keywordflow">return</span> errc::value_too_large;</div><div class="line"><a name="l00545"></a><span class="lineno"> 545</span>  }</div><div class="line"><a name="l00546"></a><span class="lineno"> 546</span>  bytes += i.size();</div><div class="line"><a name="l00547"></a><span class="lineno"> 547</span>  }</div><div class="line"><a name="l00548"></a><span class="lineno"> 548</span>  <span class="keywordflow">return</span> <a class="code" href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">lock</a>(reqs.offset, bytes, <span class="keyword">false</span>, d);</div><div class="line"><a name="l00549"></a><span class="lineno"> 549</span>  }</div><div class="ttc" id="classllfio__v2__xxx_1_1io__handle_html_a29cc9f2525f78dd73f8402cb59d97212"><div class="ttname"><a href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">llfio_v2_xxx::io_handle::lock</a></div><div class="ttdeci">virtual result< extent_guard > lock(extent_type offset, extent_type bytes, bool exclusive=true, deadline d=deadline()) noexcept</div><div class="ttdoc">Tries to lock the range of bytes specified for shared or exclusive access. Be aware this passes throu...</div></div> </div><!-- fragment --> </div> </div> @@ -984,7 +928,7 @@ For portability, you can only assume that barriers write order for a single hand </table> </div><div class="memdoc"> <p>This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. </p> -<div class="fragment"><div class="line"><a name="l00517"></a><span class="lineno"> 517</span>  {</div><div class="line"><a name="l00518"></a><span class="lineno"> 518</span>  <span class="keywordtype">size_t</span> bytes = 0;</div><div class="line"><a name="l00519"></a><span class="lineno"> 519</span>  <span class="keywordflow">for</span>(<span class="keyword">auto</span> &i : reqs.buffers)</div><div class="line"><a name="l00520"></a><span class="lineno"> 520</span>  {</div><div class="line"><a name="l00521"></a><span class="lineno"> 521</span>  <span class="keywordflow">if</span>(bytes + i.size() < bytes)</div><div class="line"><a name="l00522"></a><span class="lineno"> 522</span>  {</div><div class="line"><a name="l00523"></a><span class="lineno"> 523</span>  <span class="keywordflow">return</span> errc::value_too_large;</div><div class="line"><a name="l00524"></a><span class="lineno"> 524</span>  }</div><div class="line"><a name="l00525"></a><span class="lineno"> 525</span>  bytes += i.size();</div><div class="line"><a name="l00526"></a><span class="lineno"> 526</span>  }</div><div class="line"><a name="l00527"></a><span class="lineno"> 527</span>  <span class="keywordflow">return</span> <a class="code" href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">lock</a>(reqs.offset, bytes, <span class="keyword">true</span>, d);</div><div class="line"><a name="l00528"></a><span class="lineno"> 528</span>  }</div><div class="ttc" id="classllfio__v2__xxx_1_1io__handle_html_a29cc9f2525f78dd73f8402cb59d97212"><div class="ttname"><a href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">llfio_v2_xxx::io_handle::lock</a></div><div class="ttdeci">virtual result< extent_guard > lock(extent_type offset, extent_type bytes, bool exclusive=true, deadline d=deadline()) noexcept</div><div class="ttdoc">Tries to lock the range of bytes specified for shared or exclusive access. Be aware this passes throu...</div></div> +<div class="fragment"><div class="line"><a name="l00552"></a><span class="lineno"> 552</span>  {</div><div class="line"><a name="l00553"></a><span class="lineno"> 553</span>  <span class="keywordtype">size_t</span> bytes = 0;</div><div class="line"><a name="l00554"></a><span class="lineno"> 554</span>  <span class="keywordflow">for</span>(<span class="keyword">auto</span> &i : reqs.buffers)</div><div class="line"><a name="l00555"></a><span class="lineno"> 555</span>  {</div><div class="line"><a name="l00556"></a><span class="lineno"> 556</span>  <span class="keywordflow">if</span>(bytes + i.size() < bytes)</div><div class="line"><a name="l00557"></a><span class="lineno"> 557</span>  {</div><div class="line"><a name="l00558"></a><span class="lineno"> 558</span>  <span class="keywordflow">return</span> errc::value_too_large;</div><div class="line"><a name="l00559"></a><span class="lineno"> 559</span>  }</div><div class="line"><a name="l00560"></a><span class="lineno"> 560</span>  bytes += i.size();</div><div class="line"><a name="l00561"></a><span class="lineno"> 561</span>  }</div><div class="line"><a name="l00562"></a><span class="lineno"> 562</span>  <span class="keywordflow">return</span> <a class="code" href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">lock</a>(reqs.offset, bytes, <span class="keyword">true</span>, d);</div><div class="line"><a name="l00563"></a><span class="lineno"> 563</span>  }</div><div class="ttc" id="classllfio__v2__xxx_1_1io__handle_html_a29cc9f2525f78dd73f8402cb59d97212"><div class="ttname"><a href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">llfio_v2_xxx::io_handle::lock</a></div><div class="ttdeci">virtual result< extent_guard > lock(extent_type offset, extent_type bytes, bool exclusive=true, deadline d=deadline()) noexcept</div><div class="ttdoc">Tries to lock the range of bytes specified for shared or exclusive access. Be aware this passes throu...</div></div> </div><!-- fragment --> </div> </div> @@ -1014,7 +958,8 @@ For portability, you can only assume that barriers write order for a single hand <p>The <em>maximum</em> number of buffers which a single read or write syscall can process at a time for this specific open handle. On POSIX, this is known as <code>IOV_MAX</code>. </p> <p>Note that the actual number of buffers accepted for a read or a write may be significantly lower than this system-defined limit, depending on available resources. The <code>read()</code> or <code>write()</code> call will return the buffers accepted.</p> <p>Note also that some OSs will error out if you supply more than this limit to <code>read()</code> or <code>write()</code>, but other OSs do not. Some OSs guarantee that each i/o syscall has effects atomically visible or not to other i/o, other OSs do not.</p> -<p>Microsoft Windows and OS X does not implement scatter-gather file i/o syscalls. Thus this function will always return <code>1</code> in that situation. </p> +<p>OS X does not implement scatter-gather file i/o syscalls. Thus this function will always return <code>1</code> in that situation.</p> +<p>Microsoft Windows <em>may</em> implement scatter-gather file i/o under very limited circumstances. Most of the time this function will return <code>1</code>. </p> </div> </div> @@ -1048,6 +993,51 @@ For portability, you can only assume that barriers write order for a single hand </div> </div> +<a id="ac5222904f116c9beb0515a4a5aa850bf"></a> +<h2 class="memtitle"><span class="permalink"><a href="#ac5222904f116c9beb0515a4a5aa850bf">◆ </a></span>QUICKCPPLIB_BITFIELD_BEGIN()</h2> + +<div class="memitem"> +<div class="memproto"> +<table class="mlabels"> + <tr> + <td class="mlabels-left"> + <table class="memname"> + <tr> + <td class="memname">llfio_v2_xxx::handle::QUICKCPPLIB_BITFIELD_BEGIN </td> + <td>(</td> + <td class="paramtype">flag </td> + <td class="paramname"></td><td>)</td> + <td></td> + </tr> + </table> + </td> + <td class="mlabels-right"> +<span class="mlabels"><span class="mlabel">inline</span><span class="mlabel">inherited</span></span> </td> + </tr> +</table> +</div><div class="memdoc"> + +<p>Bitwise flags which can be specified. </p> +<p>< No flags </p><pre class="fragment">Unlinks the file on handle close. On POSIX, this simply unlinks whatever is pointed +</pre><p> to by <code>path()</code> upon the call of <code>close()</code> if and only if the inode matches. On Windows, if you are on Windows 10 1709 or later, exactly the same thing occurs. If on previous editions of Windows, the file entry does not disappears but becomes unavailable for anyone else to open with an <code>errc::resource_unavailable_try_again</code> error return. Because this is confusing, unless the <code>win_disable_unlink_emulation</code> flag is also specified, this POSIX behaviour is somewhat emulated by LLFIO on older Windows by renaming the file to a random name on <code>close()</code> causing it to appear to have been unlinked immediately.</p> +<p>Some kernel caching modes have unhelpfully inconsistent behaviours in getting your data onto storage, so by default unless this flag is specified LLFIO adds extra fsyncs to the following operations for the caching modes specified below: truncation of file length either explicitly or during file open. closing of the handle either explicitly or in the destructor.</p> +<p>Additionally on Linux only to prevent loss of file metadata: On the parent directory whenever a file might have been created. On the parent directory on file close.</p> +<p>This only occurs for these kernel caching modes: caching::none caching::reads caching::reads_and_metadata caching::safety_barriers</p> +<p><code>file_handle::unlink()</code> could accidentally delete the wrong file if someone has renamed the open file handle since the time it was opened. To prevent this occuring, where the OS doesn't provide race free unlink-by-open-handle we compare the inode of the path we are about to unlink with that of the open handle before unlinking. </p><dl class="section warning"><dt>Warning</dt><dd>This does not prevent races where in between the time of checking the inode and executing the unlink a third party changes the item about to be unlinked. Only operating systems with a true race-free unlink syscall are race free.</dd></dl> +<p>Ask the OS to disable prefetching of data. This can improve random i/o performance.</p> +<p>Ask the OS to maximise prefetching of data, possibly prefetching the entire file into kernel cache. This can improve sequential i/o performance.</p> +<p>< See the documentation for <code>unlink_on_first_close</code> </p><pre class="fragment">Microsoft Windows NTFS, having been created in the late 1980s, did not originally +</pre><p> implement extents-based storage and thus could only represent sparse files via efficient compression of intermediate zeros. With NTFS v3.0 (Microsoft Windows 2000), a proper extents-based on-storage representation was added, thus allowing only 64Kb extent chunks written to be stored irrespective of whatever the maximum file extent was set to.</p> +<p>For various historical reasons, extents-based storage is disabled by default in newly created files on NTFS, unlike in almost every other major filing system. You have to explicitly "opt in" to extents-based storage.</p> +<p>As extents-based storage is nearly cost free on NTFS, LLFIO by default opts in to extents-based storage for any empty file it creates. If you don't want this, you can specify this flag to prevent that happening.</p> +<p>Filesystems tend to be embarrassingly parallel for operations performed to different inodes. Where LLFIO performs i/o to multiple inodes at a time, it will use OpenMP or the Parallelism or Concurrency standard library extensions to usually complete the operation in constant rather than linear time. If you don't want this default, you can disable default using this flag.</p> +<p>Microsoft Windows NTFS has the option, when creating a directory, to set whether leafname lookup will be case sensitive. This is the only way of getting exact POSIX semantics on Windows without resorting to editing the system registry, however it also affects all code doing lookups within that directory, so we must default it to off.</p> +<p>< On Windows, create any new handles with OVERLAPPED semantics</p> +<p>< Using insane POSIX byte range locks</p> +<p>< This is an inode created with no representation on the filing system </p> +<div class="fragment"><div class="line"><a name="l00098"></a><span class="lineno"> 98</span>  {</div><div class="line"><a name="l00099"></a><span class="lineno"> 99</span>  none = 0, <span class="comment">//!< No flags</span></div><div class="line"><a name="l00100"></a><span class="lineno"> 100</span> <span class="comment"></span><span class="comment"> /*! Unlinks the file on handle close. On POSIX, this simply unlinks whatever is pointed</span></div><div class="line"><a name="l00101"></a><span class="lineno"> 101</span> <span class="comment"> to by `path()` upon the call of `close()` if and only if the inode matches. On Windows,</span></div><div class="line"><a name="l00102"></a><span class="lineno"> 102</span> <span class="comment"> if you are on Windows 10 1709 or later, exactly the same thing occurs. If on previous</span></div><div class="line"><a name="l00103"></a><span class="lineno"> 103</span> <span class="comment"> editions of Windows, the file entry does not disappears but becomes unavailable for</span></div><div class="line"><a name="l00104"></a><span class="lineno"> 104</span> <span class="comment"> anyone else to open with an `errc::resource_unavailable_try_again` error return. Because this is confusing, unless the</span></div><div class="line"><a name="l00105"></a><span class="lineno"> 105</span> <span class="comment"> `win_disable_unlink_emulation` flag is also specified, this POSIX behaviour is</span></div><div class="line"><a name="l00106"></a><span class="lineno"> 106</span> <span class="comment"> somewhat emulated by LLFIO on older Windows by renaming the file to a random name on `close()`</span></div><div class="line"><a name="l00107"></a><span class="lineno"> 107</span> <span class="comment"> causing it to appear to have been unlinked immediately.</span></div><div class="line"><a name="l00108"></a><span class="lineno"> 108</span> <span class="comment"> */</span></div><div class="line"><a name="l00109"></a><span class="lineno"> 109</span>  unlink_on_first_close = 1U << 0U,</div><div class="line"><a name="l00110"></a><span class="lineno"> 110</span> <span class="comment"></span></div><div class="line"><a name="l00111"></a><span class="lineno"> 111</span> <span class="comment"> /*! Some kernel caching modes have unhelpfully inconsistent behaviours</span></div><div class="line"><a name="l00112"></a><span class="lineno"> 112</span> <span class="comment"> in getting your data onto storage, so by default unless this flag is</span></div><div class="line"><a name="l00113"></a><span class="lineno"> 113</span> <span class="comment"> specified LLFIO adds extra fsyncs to the following operations for the</span></div><div class="line"><a name="l00114"></a><span class="lineno"> 114</span> <span class="comment"> caching modes specified below:</span></div><div class="line"><a name="l00115"></a><span class="lineno"> 115</span> <span class="comment"> * truncation of file length either explicitly or during file open.</span></div><div class="line"><a name="l00116"></a><span class="lineno"> 116</span> <span class="comment"> * closing of the handle either explicitly or in the destructor.</span></div><div class="line"><a name="l00117"></a><span class="lineno"> 117</span> <span class="comment"></span></div><div class="line"><a name="l00118"></a><span class="lineno"> 118</span> <span class="comment"> Additionally on Linux only to prevent loss of file metadata:</span></div><div class="line"><a name="l00119"></a><span class="lineno"> 119</span> <span class="comment"> * On the parent directory whenever a file might have been created.</span></div><div class="line"><a name="l00120"></a><span class="lineno"> 120</span> <span class="comment"> * On the parent directory on file close.</span></div><div class="line"><a name="l00121"></a><span class="lineno"> 121</span> <span class="comment"></span></div><div class="line"><a name="l00122"></a><span class="lineno"> 122</span> <span class="comment"> This only occurs for these kernel caching modes:</span></div><div class="line"><a name="l00123"></a><span class="lineno"> 123</span> <span class="comment"> * caching::none</span></div><div class="line"><a name="l00124"></a><span class="lineno"> 124</span> <span class="comment"> * caching::reads</span></div><div class="line"><a name="l00125"></a><span class="lineno"> 125</span> <span class="comment"> * caching::reads_and_metadata</span></div><div class="line"><a name="l00126"></a><span class="lineno"> 126</span> <span class="comment"> * caching::safety_barriers</span></div><div class="line"><a name="l00127"></a><span class="lineno"> 127</span> <span class="comment"> */</span></div><div class="line"><a name="l00128"></a><span class="lineno"> 128</span>  disable_safety_barriers = 1U << 2U,<span class="comment"></span></div><div class="line"><a name="l00129"></a><span class="lineno"> 129</span> <span class="comment"> /*! `file_handle::unlink()` could accidentally delete the wrong file if someone has</span></div><div class="line"><a name="l00130"></a><span class="lineno"> 130</span> <span class="comment"> renamed the open file handle since the time it was opened. To prevent this occuring,</span></div><div class="line"><a name="l00131"></a><span class="lineno"> 131</span> <span class="comment"> where the OS doesn't provide race free unlink-by-open-handle we compare the inode of</span></div><div class="line"><a name="l00132"></a><span class="lineno"> 132</span> <span class="comment"> the path we are about to unlink with that of the open handle before unlinking.</span></div><div class="line"><a name="l00133"></a><span class="lineno"> 133</span> <span class="comment"> \warning This does not prevent races where in between the time of checking the inode</span></div><div class="line"><a name="l00134"></a><span class="lineno"> 134</span> <span class="comment"> and executing the unlink a third party changes the item about to be unlinked. Only</span></div><div class="line"><a name="l00135"></a><span class="lineno"> 135</span> <span class="comment"> operating systems with a true race-free unlink syscall are race free.</span></div><div class="line"><a name="l00136"></a><span class="lineno"> 136</span> <span class="comment"> */</span></div><div class="line"><a name="l00137"></a><span class="lineno"> 137</span>  disable_safety_unlinks = 1U << 3U,<span class="comment"></span></div><div class="line"><a name="l00138"></a><span class="lineno"> 138</span> <span class="comment"> /*! Ask the OS to disable prefetching of data. This can improve random</span></div><div class="line"><a name="l00139"></a><span class="lineno"> 139</span> <span class="comment"> i/o performance.</span></div><div class="line"><a name="l00140"></a><span class="lineno"> 140</span> <span class="comment"> */</span></div><div class="line"><a name="l00141"></a><span class="lineno"> 141</span>  disable_prefetching = 1U << 4U,<span class="comment"></span></div><div class="line"><a name="l00142"></a><span class="lineno"> 142</span> <span class="comment"> /*! Ask the OS to maximise prefetching of data, possibly prefetching the entire file</span></div><div class="line"><a name="l00143"></a><span class="lineno"> 143</span> <span class="comment"> into kernel cache. This can improve sequential i/o performance.</span></div><div class="line"><a name="l00144"></a><span class="lineno"> 144</span> <span class="comment"> */</span></div><div class="line"><a name="l00145"></a><span class="lineno"> 145</span>  maximum_prefetching = 1U << 5U,</div><div class="line"><a name="l00146"></a><span class="lineno"> 146</span> </div><div class="line"><a name="l00147"></a><span class="lineno"> 147</span>  win_disable_unlink_emulation = 1U << 24U, <span class="comment">//!< See the documentation for `unlink_on_first_close`</span></div><div class="line"><a name="l00148"></a><span class="lineno"> 148</span> <span class="comment"></span><span class="comment"> /*! Microsoft Windows NTFS, having been created in the late 1980s, did not originally</span></div><div class="line"><a name="l00149"></a><span class="lineno"> 149</span> <span class="comment"> implement extents-based storage and thus could only represent sparse files via</span></div><div class="line"><a name="l00150"></a><span class="lineno"> 150</span> <span class="comment"> efficient compression of intermediate zeros. With NTFS v3.0 (Microsoft Windows 2000),</span></div><div class="line"><a name="l00151"></a><span class="lineno"> 151</span> <span class="comment"> a proper extents-based on-storage representation was added, thus allowing only 64Kb</span></div><div class="line"><a name="l00152"></a><span class="lineno"> 152</span> <span class="comment"> extent chunks written to be stored irrespective of whatever the maximum file extent</span></div><div class="line"><a name="l00153"></a><span class="lineno"> 153</span> <span class="comment"> was set to.</span></div><div class="line"><a name="l00154"></a><span class="lineno"> 154</span> <span class="comment"></span></div><div class="line"><a name="l00155"></a><span class="lineno"> 155</span> <span class="comment"> For various historical reasons, extents-based storage is disabled by default in newly</span></div><div class="line"><a name="l00156"></a><span class="lineno"> 156</span> <span class="comment"> created files on NTFS, unlike in almost every other major filing system. You have to</span></div><div class="line"><a name="l00157"></a><span class="lineno"> 157</span> <span class="comment"> explicitly "opt in" to extents-based storage.</span></div><div class="line"><a name="l00158"></a><span class="lineno"> 158</span> <span class="comment"></span></div><div class="line"><a name="l00159"></a><span class="lineno"> 159</span> <span class="comment"> As extents-based storage is nearly cost free on NTFS, LLFIO by default opts in to</span></div><div class="line"><a name="l00160"></a><span class="lineno"> 160</span> <span class="comment"> extents-based storage for any empty file it creates. If you don't want this, you</span></div><div class="line"><a name="l00161"></a><span class="lineno"> 161</span> <span class="comment"> can specify this flag to prevent that happening.</span></div><div class="line"><a name="l00162"></a><span class="lineno"> 162</span> <span class="comment"> */</span></div><div class="line"><a name="l00163"></a><span class="lineno"> 163</span>  win_disable_sparse_file_creation = 1U << 25U,<span class="comment"></span></div><div class="line"><a name="l00164"></a><span class="lineno"> 164</span> <span class="comment"> /*! Filesystems tend to be embarrassingly parallel for operations performed to different</span></div><div class="line"><a name="l00165"></a><span class="lineno"> 165</span> <span class="comment"> inodes. Where LLFIO performs i/o to multiple inodes at a time, it will use OpenMP or</span></div><div class="line"><a name="l00166"></a><span class="lineno"> 166</span> <span class="comment"> the Parallelism or Concurrency standard library extensions to usually complete the</span></div><div class="line"><a name="l00167"></a><span class="lineno"> 167</span> <span class="comment"> operation in constant rather than linear time. If you don't want this default, you can</span></div><div class="line"><a name="l00168"></a><span class="lineno"> 168</span> <span class="comment"> disable default using this flag.</span></div><div class="line"><a name="l00169"></a><span class="lineno"> 169</span> <span class="comment"> */</span></div><div class="line"><a name="l00170"></a><span class="lineno"> 170</span>  disable_parallelism = 1U << 26U,<span class="comment"></span></div><div class="line"><a name="l00171"></a><span class="lineno"> 171</span> <span class="comment"> /*! Microsoft Windows NTFS has the option, when creating a directory, to set whether</span></div><div class="line"><a name="l00172"></a><span class="lineno"> 172</span> <span class="comment"> leafname lookup will be case sensitive. This is the only way of getting exact POSIX</span></div><div class="line"><a name="l00173"></a><span class="lineno"> 173</span> <span class="comment"> semantics on Windows without resorting to editing the system registry, however it also</span></div><div class="line"><a name="l00174"></a><span class="lineno"> 174</span> <span class="comment"> affects all code doing lookups within that directory, so we must default it to off.</span></div><div class="line"><a name="l00175"></a><span class="lineno"> 175</span> <span class="comment"> */</span></div><div class="line"><a name="l00176"></a><span class="lineno"> 176</span>  win_create_case_sensitive_directory = 1U << 27U,</div><div class="line"><a name="l00177"></a><span class="lineno"> 177</span> </div><div class="line"><a name="l00178"></a><span class="lineno"> 178</span>  <span class="comment">// NOTE: IF UPDATING THIS UPDATE THE std::ostream PRINTER BELOW!!!</span></div><div class="line"><a name="l00179"></a><span class="lineno"> 179</span> </div><div class="line"><a name="l00180"></a><span class="lineno"> 180</span>  overlapped = 1U << 28U, <span class="comment">//!< On Windows, create any new handles with OVERLAPPED semantics</span></div><div class="line"><a name="l00181"></a><span class="lineno"> 181</span> <span class="comment"></span> byte_lock_insanity = 1U << 29U, <span class="comment">//!< Using insane POSIX byte range locks</span></div><div class="line"><a name="l00182"></a><span class="lineno"> 182</span> <span class="comment"></span> anonymous_inode = 1U << 30U <span class="comment">//!< This is an inode created with no representation on the filing system</span></div><div class="line"><a name="l00183"></a><span class="lineno"> 183</span> <span class="comment"></span> } QUICKCPPLIB_BITFIELD_END(flag);</div></div><!-- fragment --> +</div> +</div> <a id="a3141a85996e46a3cc6b238d321198e47"></a> <h2 class="memtitle"><span class="permalink"><a href="#a3141a85996e46a3cc6b238d321198e47">◆ </a></span>random_file()</h2> @@ -1437,7 +1427,7 @@ For portability, you can only assume that barriers write order for a single hand </table> </div><div class="memdoc"> <p>This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. </p> -<div class="fragment"><div class="line"><a name="l00500"></a><span class="lineno"> 500</span> { <span class="keywordflow">return</span> <a class="code" href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">lock</a>(offset, bytes, exclusive, deadline(std::chrono::seconds(0))); }</div><div class="ttc" id="classllfio__v2__xxx_1_1io__handle_html_a29cc9f2525f78dd73f8402cb59d97212"><div class="ttname"><a href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">llfio_v2_xxx::io_handle::lock</a></div><div class="ttdeci">virtual result< extent_guard > lock(extent_type offset, extent_type bytes, bool exclusive=true, deadline d=deadline()) noexcept</div><div class="ttdoc">Tries to lock the range of bytes specified for shared or exclusive access. Be aware this passes throu...</div></div> +<div class="fragment"><div class="line"><a name="l00535"></a><span class="lineno"> 535</span> { <span class="keywordflow">return</span> <a class="code" href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">lock</a>(offset, bytes, exclusive, deadline(std::chrono::seconds(0))); }</div><div class="ttc" id="classllfio__v2__xxx_1_1io__handle_html_a29cc9f2525f78dd73f8402cb59d97212"><div class="ttname"><a href="classllfio__v2__xxx_1_1io__handle.html#a29cc9f2525f78dd73f8402cb59d97212">llfio_v2_xxx::io_handle::lock</a></div><div class="ttdeci">virtual result< extent_guard > lock(extent_type offset, extent_type bytes, bool exclusive=true, deadline d=deadline()) noexcept</div><div class="ttdoc">Tries to lock the range of bytes specified for shared or exclusive access. Be aware this passes throu...</div></div> </div><!-- fragment --> </div> </div> @@ -1665,7 +1655,7 @@ For portability, you can only assume that barriers write order for a single hand </table> </div><div class="memdoc"> <p>This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. </p> -<div class="fragment"><div class="line"><a name="l00341"></a><span class="lineno"> 341</span>  {</div><div class="line"><a name="l00342"></a><span class="lineno"> 342</span>  const_buffer_type *_reqs = <span class="keyword">reinterpret_cast<</span>const_buffer_type *<span class="keyword">></span>(alloca(<span class="keyword">sizeof</span>(const_buffer_type) * lst.size()));</div><div class="line"><a name="l00343"></a><span class="lineno"> 343</span>  memcpy(_reqs, lst.begin(), <span class="keyword">sizeof</span>(const_buffer_type) * lst.size());</div><div class="line"><a name="l00344"></a><span class="lineno"> 344</span>  io_request<const_buffers_type> reqs(<a class="code" href="classllfio__v2__xxx_1_1io__handle.html#a693a8c64bb7de1a6835d6a151e37aa0e">const_buffers_type</a>(_reqs, lst.size()), offset);</div><div class="line"><a name="l00345"></a><span class="lineno"> 345</span>  <span class="keyword">auto</span> ret = <a class="code" href="classllfio__v2__xxx_1_1io__handle.html#a83884eca7b4cd09125a5cf8a155e6052">write</a>(reqs, d);</div><div class="line"><a name="l00346"></a><span class="lineno"> 346</span>  <span class="keywordflow">if</span>(ret)</div><div class="line"><a name="l00347"></a><span class="lineno"> 347</span>  {</div><div class="line"><a name="l00348"></a><span class="lineno"> 348</span>  <span class="keywordflow">return</span> ret.bytes_transferred();</div><div class="line"><a name="l00349"></a><span class="lineno"> 349</span>  }</div><div class="line"><a name="l00350"></a><span class="lineno"> 350</span>  <span class="keywordflow">return</span> std::move(ret).error();</div><div class="line"><a name="l00351"></a><span class="lineno"> 351</span>  }</div><div class="ttc" id="classllfio__v2__xxx_1_1io__handle_html_a693a8c64bb7de1a6835d6a151e37aa0e"><div class="ttname"><a href="classllfio__v2__xxx_1_1io__handle.html#a693a8c64bb7de1a6835d6a151e37aa0e">llfio_v2_xxx::io_handle::const_buffers_type</a></div><div class="ttdeci">span< const_buffer_type > const_buffers_type</div><div class="ttdoc">The gather buffers type used by this handle. Guaranteed to be TrivialType apart from construction...</div><div class="ttdef"><b>Definition:</b> io_handle.hpp:165</div></div> +<div class="fragment"><div class="line"><a name="l00370"></a><span class="lineno"> 370</span>  {</div><div class="line"><a name="l00371"></a><span class="lineno"> 371</span>  const_buffer_type *_reqs = <span class="keyword">reinterpret_cast<</span>const_buffer_type *<span class="keyword">></span>(alloca(<span class="keyword">sizeof</span>(const_buffer_type) * lst.size()));</div><div class="line"><a name="l00372"></a><span class="lineno"> 372</span>  memcpy(_reqs, lst.begin(), <span class="keyword">sizeof</span>(const_buffer_type) * lst.size());</div><div class="line"><a name="l00373"></a><span class="lineno"> 373</span>  io_request<const_buffers_type> reqs(<a class="code" href="classllfio__v2__xxx_1_1io__handle.html#a693a8c64bb7de1a6835d6a151e37aa0e">const_buffers_type</a>(_reqs, lst.size()), offset);</div><div class="line"><a name="l00374"></a><span class="lineno"> 374</span>  <span class="keyword">auto</span> ret = <a class="code" href="classllfio__v2__xxx_1_1io__handle.html#a83884eca7b4cd09125a5cf8a155e6052">write</a>(reqs, d);</div><div class="line"><a name="l00375"></a><span class="lineno"> 375</span>  <span class="keywordflow">if</span>(ret)</div><div class="line"><a name="l00376"></a><span class="lineno"> 376</span>  {</div><div class="line"><a name="l00377"></a><span class="lineno"> 377</span>  <span class="keywordflow">return</span> ret.bytes_transferred();</div><div class="line"><a name="l00378"></a><span class="lineno"> 378</span>  }</div><div class="line"><a name="l00379"></a><span class="lineno"> 379</span>  <span class="keywordflow">return</span> std::move(ret).error();</div><div class="line"><a name="l00380"></a><span class="lineno"> 380</span>  }</div><div class="ttc" id="classllfio__v2__xxx_1_1io__handle_html_a693a8c64bb7de1a6835d6a151e37aa0e"><div class="ttname"><a href="classllfio__v2__xxx_1_1io__handle.html#a693a8c64bb7de1a6835d6a151e37aa0e">llfio_v2_xxx::io_handle::const_buffers_type</a></div><div class="ttdeci">span< const_buffer_type > const_buffers_type</div><div class="ttdoc">The gather buffers type used by this handle. Guaranteed to be TrivialType apart from construction...</div><div class="ttdef"><b>Definition:</b> io_handle.hpp:188</div></div> <div class="ttc" id="classllfio__v2__xxx_1_1io__handle_html_a83884eca7b4cd09125a5cf8a155e6052"><div class="ttname"><a href="classllfio__v2__xxx_1_1io__handle.html#a83884eca7b4cd09125a5cf8a155e6052">llfio_v2_xxx::io_handle::write</a></div><div class="ttdeci">virtual io_result< const_buffers_type > write(io_request< const_buffers_type > reqs, deadline d=deadline()) noexcept</div><div class="ttdoc">Write data to the open handle. </div></div> </div><!-- fragment --> </div> |