postgres++ async C++ driver is a thin libpq wrapper in C++ for PostgreSQL that aims to make libpq easier to use. It has asynchronous behavior and depends on Boost.ASIO for async operations. It makes use of C++11 variadic templates for parameter-ed functions like PQsendQueryParams.
License: BSD 3-Clause "New" or "Revised" License
I'm sure that i installed all librarys required in project.gyp. e.g. libpq.so, libboost_system.so, libboost_log.so, libboost_log_setup.so.
gcc version is 7.3.1 20180312 (GCC) which support c++14 built-in.
boost version is 1.66.0.
linux version is archlinux 4.15.15-1-ARCH.
Could you give me a help? Thanks very much.
I managed to build your project with Visual Studio and include and use it in a new Visual Studio project with the following (trivial) code:
#include <iostream>
#include "boost/asio.hpp"
#include "connection.hpp"
#include "async_exec.hpp"
int main()
{
boost::asio::io_context ioc;
postgrespp::connection c{ ioc, "<valid connection info>" };
postgrespp::async_exec(c, "SELECT 1", [](postgrespp::result res) { std::cout << res.ok(); });
ioc.run();
}However, when running the program I get an error in postgrespp::basic_connection::underlying_handle() (file include\basic_connection.hpp), even before printing res.ok() in the lambda, saying:
Exception thrown: read access violation.
this was 0xFFFFFFFFFFFFFF67.
This does not happen when I build as Release (i. e. with optimizations enabled). Thus I assume this is caused by mistakenly accessing some de-allocated/released memory (from some move or anything): In Debug build it is explicitly overwritten with some invalid value to make the provoked UB of accessing it noticeable. In Release build that invalid memory is not being overwritten, allowing the program to access it and deceptively complete "successfully".
The problem arises in the current master (a8f82b1) as well as on tag 0.2.2 (d789d70). Let me know if I can help you with any more details.
See the stack trace below (run with files from a8f82b1, postgrespp-testings.exe is the project name).
postgrespp-testings.exe!postgrespp::basic_connection::underlying_handle() Line 119 C++
postgrespp-testings.exe!postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::on_write_ready(const boost::system::error_code & ec) Line 116 C++
[External Code]
postgrespp-testings.exe!boost::asio::detail::binder1<std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &>,boost::system::error_code>::operator()() Line 66 C++
postgrespp-testings.exe!boost::asio::asio_handler_invoke<boost::asio::detail::binder1<std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &>,boost::system::error_code>>(boost::asio::detail::binder1<std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &>,boost::system::error_code> & function, ...) Line 92 C++
postgrespp-testings.exe!boost_asio_handler_invoke_helpers::invoke<boost::asio::detail::binder1<std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &>,boost::system::error_code>,std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &>>(boost::asio::detail::binder1<std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &>,boost::system::error_code> & function, std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &> & context) Line 56 C++
postgrespp-testings.exe!boost::asio::detail::handler_work<std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &>,boost::asio::execution::any_executor<boost::asio::execution::context_as_t<boost::asio::execution_context &>,boost::asio::execution::detail::blocking::never_t<0>,boost::asio::execution::prefer_only<boost::asio::execution::detail::blocking::possibly_t<0>>,boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::tracked_t<0>>,boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::untracked_t<0>>,boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::fork_t<0>>,boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::continuation_t<0>>>,void>::complete<boost::asio::detail::binder1<std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &>,boost::system::error_code>>(boost::asio::detail::binder1<std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &>,boost::system::error_code> & function, std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &> & handler) Line 426 C++
postgrespp-testings.exe!boost::asio::detail::win_iocp_wait_op<std::_Binder<std::_Unforced,void (__cdecl postgrespp::socket_operations<postgrespp::basic_transaction<void,void>>::*)(boost::system::error_code const &),postgrespp::socket_operations<postgrespp::basic_transaction<void,void>> *,std::_Ph<1> const &>,boost::asio::execution::any_executor<boost::asio::execution::context_as_t<boost::asio::execution_context &>,boost::asio::execution::detail::blocking::never_t<0>,boost::asio::execution::prefer_only<boost::asio::execution::detail::blocking::possibly_t<0>>,boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::tracked_t<0>>,boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::untracked_t<0>>,boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::fork_t<0>>,boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::continuation_t<0>>>>::do_complete(void * owner, boost::asio::detail::win_iocp_operation * base, const boost::system::error_code & result_ec, unsigned __int64 __formal) Line 111 C++
postgrespp-testings.exe!boost::asio::detail::win_iocp_operation::complete(void * owner, const boost::system::error_code & ec, unsigned __int64 bytes_transferred) Line 48 C++
postgrespp-testings.exe!boost::asio::detail::win_iocp_io_context::do_one(unsigned long msec, boost::asio::detail::win_iocp_thread_info & this_thread, boost::system::error_code & ec) Line 469 C++
postgrespp-testings.exe!boost::asio::detail::win_iocp_io_context::run(boost::system::error_code & ec) Line 204 C++
postgrespp-testings.exe!boost::asio::io_context::run() Line 63 C++
postgrespp-testings.exe!main() Line 14 C++
[External Code]
Does this library support binding arrays to a query param? This will be the primary reason for me to switch over from Rust which has been hell on productivity
I am not able to retrieve numeric return values . here is an example function that returns out4 and out5 as numeric.
CREATE OR REPLACE FUNCTION common.my_function(p1 integer, p2 integer, p3 text, p4 numeric, p5 text)
RETURNS TABLE(out1 text, out2 text, out3 text, out4 numeric, out5 numeric)
LANGUAGE plpgsql
AS
BEGIN
-- Do some processing here
-- ...
-- Return the output values
RETURN QUERY
SELECT
'output1' AS out1,
'output2' AS out2,
'output3' AS out3,
123.45 AS out4,
678.90 AS out5;
END;
;
in result.hpp I have added
PGresult* underlying_result_handle() { return res_;}
Here is test code cpp code,
std::string query = fmt::format("select out1 "o1", out2 "o2",out3 "o3", out4 "o4" ,out5 "o5" from common.my_function ({}, {}, '{}', {}, '{}')",
fmt::arg("p1", 1),
fmt::arg("p2", 1),
fmt::arg("p3", "Delete"),
fmt::arg("p4", 1),
fmt::arg("p5", "USD"));
auto result_future = async_exec(*_dbconn,
query,
postgrespp::use_future);
postgrespp::result result = result_future.get();
if (result.ok()) {
auto result_handle = result.underlying_result_handle();
std::cout << "Rows=" << PQntuples(result_handle) << std::endl;
std::string o1,o2, o3;
double o4, o5;
std::cout << std::atof(PQgetvalue(result_handle, 0, 3)) << std::endl; ///always prints 0
}
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