Actually a simple note to the previous article.
– C: libevent seems to give best performance, but also low level.
– C++: drogon has websocket support, but no sse. async.
– C++: poco is sync.
– C++: workflow is low level, hard to use. wfrest has convenient apis, sse support in trunk.
– C++: boost/beast has poor performance, and cannot utilize multi-core cpu.
– C++: oatpp is async, but complex framework.
– Better use high level languages like Java or Go if running a web application.
Verified on CentOS7 and Windows 10.
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nohup ./v2ray run config.json & export http_proxy="socks5://localhost:xxxxx" export https_proxy="socks5://localhost:xxxxx" |
v2ray unblocks github access from mainland China. Install v2ray clients and set IE proxy _only_ on Windows, bootstrap.bat & vcpkg.exe picks it automatically.
Download from: https://github.com/microsoft/vcpkg/releases
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cd vcpkg-2022.08.15 ./bootstrap-vcpkg.sh |
Export vcpkg-2022.08.15 directory as ${VCPKG_ROOT}.
The drogon framework is a high performance application framework, including client & server supports. vcpkg builds static(*.a) library by default, use x64-linux-dynamic for dynamic(*.so) library. The repo version requires g++-8 to build, install from CentOS SCL:
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yum install centos-release-scl yum install devtoolset-8 echo '. /opt/rh/devtoolset-8/enable' | tee -a /etc/profile . /etc/profile # export CC=/opt/rh/devtoolset-8/root/usr/bin/gcc # export CXX=/opt/rh/devtoolset-8/root/usr/bin/g++ |
To build with g++-7, manually install boost-filesystem package in vcpkg, and edit ${VCPKG_ROOT}/ports/drogon/portfile.cmake and comment out:
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... #-DCMAKE_DISABLE_FIND_PACKAGE_Boost=ON ... |
On Windows, open the command line for Visual Studio develop environment.
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./vcpkg search drogon # linux, drogon[postgres] dynamic build is not well supported on linux ./vcpkg install drogon[ctl,mysql,orm,redis] --triplet=x64-linux-dynamic # windows vcpkg install drogon[ctl,mysql,orm,redis] --triplet=x64-windows |
If openssl build fails, run:
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yum install perl-IPC-Cmd perl-Data-Dumper |
If other errors, try to update to recent github ports. In my case, libmariadb build failed, that have been fixed in master.
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./vcpkg export drogon:x64-linux-dynamic --zip # Zip archive exported at: ${VCPKG_ROOT}/vcpkg-export-20220928-102415.zip # To use the exported libraries in CMake projects use: # -DCMAKE_TOOLCHAIN_FILE=[...]/scripts/buildsystems/vcpkg.cmake |
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// drogon_server.cpp #include <drogon/drogon.h> using namespace drogon; int main() { app().registerHandler( "/text", [](const HttpRequestPtr &, std::function<void(const HttpResponsePtr &)> &&callback) { auto resp = HttpResponse::newHttpResponse(); resp->setBody("Hello World!"); callback(resp); }, {Get}); app().registerHandler( "/json", [](const HttpRequestPtr &, std::function<void(const HttpResponsePtr &)> &&callback) { Json::Value json; json["Message"] = "Hello World!"; auto resp = HttpResponse::newHttpJsonResponse(json); callback(resp); }, {Get}); LOG_INFO << "Server running on 0.0.0.0:8099"; app().addListener("0.0.0.0", 8099) .setThreadNum(24) .enableServerHeader(false) .enableDateHeader(false) //.enableRunAsDaemon() .run(); } |
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# CMakeLists.txt cmake_minimum_required(VERSION 3.15) project(drogon_server CXX) set(CMAKE_CXX_STANDARD 17) message("Got CMAKE_PREFIX_PATH: ${CMAKE_PREFIX_PATH}") find_package(Drogon CONFIG REQUIRED) add_executable(drogon_server drogon_server.cpp) target_link_libraries(drogon_server PRIVATE Drogon::Drogon) |
Linux dynamic build is community supported, invoke cmake with:
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# linux cmake -B build -S . -DCMAKE_TOOLCHAIN_FILE=${VCPKG_ROOT}/scripts/buildsystems/vcpkg.cmake -DVCPKG_TARGET_TRIPLET=x64-linux-dynamic # windows cmake -B build -S . -DCMAKE_TOOLCHAIN_FILE=${VCPKG_ROOT}/scripts/buildsystems/vcpkg.cmake -DVCPKG_TARGET_TRIPLET=x64-windows |
Now build with make or Visual Studio.
add a vcpkg.json file:
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{ "name": "drogon-server", "version-string": "0.1.0", "dependencies": [ { "name": "drogon", "version>=": "1.7.5", "features": [ "ctl", "mysql", "orm", "redis" ] }, "openssl" ], "overrides": [ { "name": "drogon", "version": "1.8.0" }, { "name": "openssl", "version-string": "1.1.1n#1" } ], "builtin-baseline": "4e73d1b47a7e5428e2ea9dbec43b136a6632a7cb" } |
It sticks to drogon 1.8.0 and openssl 1.1.1n. ${VCPKG_ROOT} now required to be a git repository. In your project directory, install specific versions of libraries by running:
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# linux ./vcpkg --feature-flags="versions" install --triplet=x64-linux-dynamic # windows vcpkg --feature-flags="versions" install --triplet=x64-windows |
Run cmake:
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# linux cmake -B build -S . -DCMAKE_TOOLCHAIN_FILE=${VCPKG_ROOT}/scripts/buildsystems/vcpkg.cmake -DVCPKG_TARGET_TRIPLET=x64-linux-dynamic # windows cmake -B build -S . -DCMAKE_TOOLCHAIN_FILE=${VCPKG_ROOT}/scripts/buildsystems/vcpkg.cmake -DVCPKG_TARGET_TRIPLET=x64-windows cd build make |
Now ldd output shows openssl 1.1 (default build is 3.0):
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ldd drogon_server linux-vdso.so.1 => (0x00007ffc1bf9c000) libdrogon.so.1 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libdrogon.so.1 (0x00007fbbd2329000) libtrantor.so.1 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libtrantor.so.1 (0x00007fbbd1ea0000) libpthread.so.0 => /lib64/libpthread.so.0 (0x00007fbbd1c84000) libjsoncpp.so.25 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libjsoncpp.so.25 (0x00007fbbd19ed000) libstdc++.so.6 => /lib64/libstdc++.so.6 (0x00007fbbd16e5000) libm.so.6 => /lib64/libm.so.6 (0x00007fbbd13e3000) libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00007fbbd11cd000) libc.so.6 => /lib64/libc.so.6 (0x00007fbbd0dff000) libdl.so.2 => /lib64/libdl.so.2 (0x00007fbbd0bfb000) libmariadb.so.3 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libmariadb.so.3 (0x00007fbbd098d000) libz.so.1 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libz.so.1 (0x00007fbbd0769000) libssl.so.1.1 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libssl.so.1.1 (0x00007fbbd04d1000) libcrypto.so.1.1 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libcrypto.so.1.1 (0x00007fbbcffd7000) libbrotlidec.so.1 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libbrotlidec.so.1 (0x00007fbbcfdb6000) libbrotlienc.so.1 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libbrotlienc.so.1 (0x00007fbbcf85c000) libbrotlicommon.so.1 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libbrotlicommon.so.1 (0x00007fbbcf63a000) libhiredis.so.1.0.0 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libhiredis.so.1.0.0 (0x00007fbbcf424000) /lib64/ld-linux-x86-64.so.2 (0x00007fbbd2ebc000) libcares.so.2 => ./vcpkg_installed/x64-linux-dynamic/debug/lib/libcares.so.2 (0x00007fbbcf205000) |
The only difference is the existence of vcpkg.json file, when using versioning.
If you change the root path of vcpkg, better clean up the cache, or build may fail. It’s $HOME/.cache/vcpkg/archives under Linux, and %LOCALAPPDATA%\vcpkg\archives under Windows.
Starting with 1.56, boost/asio provides asio::spawn() to work with coroutines. Just paste the sample code here, with minor modifications:
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#include <boost/asio.hpp> #include <boost/asio/spawn.hpp> #include <boost/bind.hpp> #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> #include <iostream> using namespace std; using boost::asio::ip::tcp; class session: public boost::enable_shared_from_this<session> { public: explicit session(boost::asio::io_service &io_service) : socket_(io_service), timer_(io_service), strand_(io_service) { } tcp::socket &socket() { return socket_; } void go() { boost::asio::spawn(strand_, boost::bind(&session::echo, shared_from_this(), _1)); boost::asio::spawn(strand_, boost::bind(&session::timeout, shared_from_this(), _1)); } private: void echo(boost::asio::yield_context yield) { try { char data[128]; while (true) { timer_.expires_from_now(boost::posix_time::seconds(10)); size_t n = socket_.async_read_some(boost::asio::buffer(data), yield); boost::asio::async_write(socket_, boost::asio::buffer(data, n), yield); } } catch (exception &) { socket_.close(); timer_.cancel(); } } void timeout(boost::asio::yield_context yield) { while (socket_.is_open()) { boost::system::error_code ignored_ec; timer_.async_wait(yield[ignored_ec]); if (timer_.expires_from_now() <= boost::posix_time::seconds(0)) { socket_.close(); } } } tcp::socket socket_; boost::asio::deadline_timer timer_; boost::asio::io_service::strand strand_; }; void do_accept(boost::asio::io_service &io_service, unsigned short port, boost::asio::yield_context yield) { tcp::acceptor acceptor(io_service, tcp::endpoint(tcp::v4(), port)); while (true) { boost::system::error_code ec; boost::shared_ptr<session> new_session(new session(io_service)); acceptor.async_accept(new_session->socket(), yield[ec]); if (!ec) { new_session->go(); } } } int main() { try { boost::asio::io_service io_service; boost::asio::spawn(io_service, boost::bind(do_accept, boost::ref(io_service), 2222, _1)); io_service.run(); } catch (exception &e) { cerr << "Exception: " << e.what() << endl; } return 0; } |
The Python in my previous article can be used to work with the code above. I also tried to write a TCP server with only boost::coroutines classes. select() is used, since I want the code to be platform independent. NOTE: with coroutines, we have only _one_ thread.
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#ifdef _WIN32 #include <winsock2.h> #include <ws2tcpip.h> #include <windows.h> #pragma comment(lib, "ws2_32.lib") #pragma warning(disable: 4996) #define sock_send(s, str, len) send(s, str, len, 0) #define sock_close(s) closesocket(s) #else #include <arpa/inet.h> #include <sys/types.h> #include <sys/socket.h> #define sock_send(s, str, len) send(s, str, len, MSG_NOSIGNAL) #define sock_close(s) close(s) #endif #include <cerrno> #include <cstdio> #include <cstring> #include <iostream> #include <list> #include <boost/bind.hpp> #include <boost/coroutine/all.hpp> #include <boost/shared_ptr.hpp> using namespace std; #ifdef _WIN32 struct Win32SocketWrapper { Win32SocketWrapper() { WSADATA wsaData; WSAStartup(0x0202, &wsaData); } ~Win32SocketWrapper() { WSACleanup(); } } g_win32_socket_wrapper; #endif class session { typedef boost::coroutines::symmetric_coroutine<void> coro_t; public: explicit session(int sock) : socket_(sock) { echo_coro_ = coro_t::call_type(boost::bind(&session::echo, this, _1)); } int socket() { return socket_; } void go() { echo_coro_(); } void echo(coro_t::yield_type &yield) { int rc; char buffer[128]; while (true) { memset(buffer, 0, sizeof(buffer)); yield(); rc = recv(socket_, buffer, sizeof(buffer), 0); if (rc == 0 || rc == -1) { /* close or error */ printf("socket[%d] closed, rc=%d..\n", socket_, rc); sock_close(socket_); socket_ = -1; /* do not release here, or the whole coroutine context will be invalid.. */ break; } else { sock_send(socket_, buffer, rc); } } } private: int socket_; coro_t::call_type echo_coro_; }; void event_loop(int server_sock) { list<boost::shared_ptr<session> > session_list; int rc, maxfd, client_sock; fd_set rdset; struct sockaddr_in client_addr; size_t addr_size = sizeof(struct sockaddr_in); while (true) { FD_ZERO(&rdset); FD_SET(server_sock, &rdset); maxfd = server_sock; list<boost::shared_ptr<session> >::iterator it = session_list.begin(); while (it != session_list.end()) { if ((*it)->socket() == -1) { session_list.erase(it++); } else { FD_SET((*it)->socket(), &rdset); if (maxfd < (*it)->socket()) { maxfd = (*it)->socket(); } ++it; } } /* max fd value plus 1 */ rc = select(maxfd+1, &rdset, 0, 0, NULL); if (rc == -1) { continue; } else { if (FD_ISSET(server_sock, &rdset)) { client_sock = (int)accept(server_sock, (struct sockaddr *)&client_addr, (socklen_t *)&addr_size); printf("socket[%d] accepted: %s:%d..\n", client_sock, inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port)); boost::shared_ptr<session> new_session(new session(client_sock)); new_session->go(); /* go first */ session_list.push_back(new_session); } for (list<boost::shared_ptr<session> >::iterator it = session_list.begin(); it != session_list.end(); ++it) { if (FD_ISSET((*it)->socket(), &rdset)) { (*it)->go(); } } } } } int main() { int rc, server_sock; struct sockaddr_in server_addr; server_sock = (int)socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); server_addr.sin_family = AF_INET; server_addr.sin_addr.s_addr = htonl(INADDR_ANY); server_addr.sin_port = htons(2222); rc = bind(server_sock, (struct sockaddr *)&server_addr, sizeof(struct sockaddr_in)); if (rc < 0) { fprintf(stderr, "bind: %s.\n", strerror(errno)); return -1; } listen(server_sock, 5); /* loop */ event_loop(server_sock); sock_close(server_sock); return 0; } |
Just take a simple note here.
The Boost Multi-index Containers Library provides a class template named multi_index_container which enables the construction of containers maintaining one or more indices with different sorting and access semantics.
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#include <string> #include <ostream> #include <boost/multi_index_container.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/identity.hpp> #include <boost/multi_index/member.hpp> #include <boost/multi_index/tag.hpp> #include <boost/lambda/lambda.hpp> using namespace std; using namespace boost::multi_index; struct auth { string m_name; string m_pass; auth(const string &name, const string &pass) : m_name(name), m_pass(pass) { } bool operator<(const auth &o) const { return m_name < o.m_name; } friend ostream &operator<<(ostream &os, const auth &a) { os << "(" << a.m_name << ", " << a.m_pass << ")"; return os; } }; struct employee { int m_id; auth m_auth; int m_hire; int m_resign; employee(int id, const string &name, const string &pass, int hire, int resign) : m_id(id), m_auth(name, pass), m_hire(hire), m_resign(resign) { } bool operator<(const employee &o) const { return m_id < o.m_id; } friend ostream &operator<<(ostream &os, const employee &e) { os << "(" << e.m_id << ", " << e.m_auth << ", " << e.m_hire << ", " << e.m_resign << ")"; return os; } }; struct auth_t { }; struct change_resign { int m_resign; change_resign(int r) : m_resign(r) { } void operator()(employee &e) { e.m_resign = m_resign; } }; typedef multi_index_container< employee, indexed_by< /* sort by employee::operator< */ ordered_unique<identity<employee> >, /* sort by less<int> on m_hire */ ordered_non_unique<member<employee, int, &employee::m_hire> >, /* sort by less<auth> on m_auth */ ordered_non_unique<tag<auth_t>, member<employee, auth, &employee::m_auth> > > > employee_set; int main() { employee_set es; es.insert(employee(1, "555", "555pass", 2012, 0)); es.insert(employee(2, "444", "444pass", 2011, 0)); es.insert(employee(3, "333", "333pass", 2013, 0)); es.insert(employee(4, "222", "222pass", 2015, 0)); es.insert(employee(5, "555", "555pass", 2014, 0)); /* dup */ typedef employee_set::nth_index<1>::type hire_index_t; typedef employee_set::index<auth_t>::type auth_index_t; cout << "Get a view to index #1 (m_hire).." << endl; hire_index_t &hire_index = es.get<1>(); std::copy(hire_index.begin(), hire_index.end(), ostream_iterator<employee>(cout, "\n")); cout << "Get a view to index tag auth_t (m_auth).." << endl; const auth_index_t &auth_index = es.get<auth_t>(); std::copy(auth_index.begin(), auth_index.end(), ostream_iterator<employee>(cout, "\n")); cout << "Find.." << endl; hire_index_t::iterator it = hire_index.find(2015); #if 0 employee t = *it; t.m_resign = 2048; hire_index.replace(it, t); #else hire_index.modify_key(it, boost::lambda::_1=1111); int old_resign = it->m_resign; hire_index.modify(it, change_resign(2048), change_resign(old_resign)); #endif cout << (*it) << endl; cout << "Find all.." << endl; pair<auth_index_t::const_iterator, auth_index_t::const_iterator> pr = auth_index.equal_range(auth("555", "")); std::copy(pr.first, pr.second, ostream_iterator<employee>(cout, "\n")); return 0; } |
Output:
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Get a view to index #1 (m_hire).. (2, (444, 444pass), 2011, 0) (1, (555, 555pass), 2012, 0) (3, (333, 333pass), 2013, 0) (5, (555, 555pass), 2014, 0) (4, (222, 222pass), 2015, 0) Get a view to index tag auth_t (m_auth).. (4, (222, 222pass), 2015, 0) (3, (333, 333pass), 2013, 0) (2, (444, 444pass), 2011, 0) (1, (555, 555pass), 2012, 0) (5, (555, 555pass), 2014, 0) Find.. (4, (222, 222pass), 1111, 2048) Find all.. (1, (555, 555pass), 2012, 0) (5, (555, 555pass), 2014, 0) |
To use with pointer values, only limited change needed as highlighted:
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#include <string> #include <ostream> #include <boost/multi_index_container.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/identity.hpp> #include <boost/multi_index/member.hpp> #include <boost/multi_index/tag.hpp> #include <boost/lambda/lambda.hpp> using namespace std; using namespace boost::multi_index; struct auth { string m_name; string m_pass; auth(const string &name, const string &pass) : m_name(name), m_pass(pass) { } bool operator<(const auth &o) const { return m_name < o.m_name; } friend ostream &operator<<(ostream &os, const auth &a) { os << "(" << a.m_name << ", " << a.m_pass << ")"; return os; } }; struct employee { int m_id; auth m_auth; int m_hire; int m_resign; employee(int id, const string &name, const string &pass, int hire, int resign) : m_id(id), m_auth(name, pass), m_hire(hire), m_resign(resign) { } bool operator<(const employee &o) const { return m_id < o.m_id; } friend ostream &operator<<(ostream &os, const employee *e) { os << "(" << e->m_id << ", " << e->m_auth << ", " << e->m_hire << ", " << e->m_resign << ")"; return os; } }; struct auth_t { }; struct change_resign { int m_resign; change_resign(int r) : m_resign(r) { } void operator()(employee *e) { e->m_resign = m_resign; } }; typedef multi_index_container< employee *, indexed_by< /* sort by employee::operator< */ ordered_unique<identity<employee> >, /* sort by less<int> on m_hire */ ordered_non_unique<member<employee, int, &employee::m_hire> >, /* sort by less<auth> on m_auth */ ordered_non_unique<tag<auth_t>, member<employee, auth, &employee::m_auth> > > > employee_set; int main() { employee_set es; es.insert(new employee(1, "555", "555pass", 2012, 0)); es.insert(new employee(2, "444", "444pass", 2011, 0)); es.insert(new employee(3, "333", "333pass", 2013, 0)); es.insert(new employee(4, "222", "222pass", 2015, 0)); es.insert(new employee(5, "555", "555pass", 2014, 0)); /* dup */ typedef employee_set::nth_index<1>::type hire_index_t; typedef employee_set::index<auth_t>::type auth_index_t; cout << "Get a view to index #1 (m_hire).." << endl; hire_index_t &hire_index = es.get<1>(); std::copy(hire_index.begin(), hire_index.end(), ostream_iterator<employee *>(cout, "\n")); cout << "Get a view to index tag auth_t (m_auth).." << endl; const auth_index_t &auth_index = es.get<auth_t>(); std::copy(auth_index.begin(), auth_index.end(), ostream_iterator<employee *>(cout, "\n")); cout << "Find.." << endl; hire_index_t::iterator it = hire_index.find(2015); #if 0 employee *t = *it; t->m_auth.m_name = "888"; /* must use replace() to notify changes in indexed fields */ hire_index.replace(it, t); #else hire_index.modify_key(it, boost::lambda::_1=1111); int old_resign = (*it)->m_resign; hire_index.modify(it, change_resign(2048), change_resign(old_resign)); #endif cout << (*it) << endl; cout << "Find all.." << endl; pair<auth_index_t::const_iterator, auth_index_t::const_iterator> pr = auth_index.equal_range(auth("555", "")); std::copy(pr.first, pr.second, ostream_iterator<employee *>(cout, "\n")); /* clear */ for (employee_set::const_iterator it = es.begin(); it != es.end(); ++it) { delete *it; } employee_set().swap(es); return 0; } |
We have JDBC in Java… and SOCI in C++… Well, it’s not so easy as it should be. To build with cmake:
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# mkdir ../build # cd ../build # set ORACLE_HOME=C:\oraclexe\app\oracle\product\10.2.0\server # cmake -G "Visual Studio 9 2008" -DMYSQL_INCLUDE_DIR="C:\Program Files\MySQL\MySQL Server 5.5\include" -DMYSQL_LIBRARIES="C:\Program Files\MySQL\MySQL Server 5.5\lib\libmysql.lib" ../soci-3.2.3 |
The documents seem outdated, many options do not work. Just managed to figure out from the *.cmake source files. You can also download the oracle instant client SDK, and re-arrange the directory structure for build.
Code snippet I extracted from its unit tests:
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#include "soci.h" #include "soci-mysql.h" //#include "soci-oracle.h" #include <ctime> #include <string> #include <iostream> #include <sstream> using namespace std; int main() { try { soci::session sql(soci::mysql, "host=192.168.1.101 db=mysql user=root password=111111"); //soci::session sql(soci::oracle, "service=192.168.1.102/ORCL user=sys password=111111"); soci::row v; /* comma operator is overloaded here.. */ soci::statement st = (sql.prepare << "SELECT * FROM user", into(v)); //soci::statement st = (sql.prepare << "SELECT * FROM SYS.USER$", into(v)); st.execute(true); /* with data exchange */ unsigned int num_fields = v.size(); cout << "fields: " << num_fields << endl; num_fields = (num_fields <= 9) ? num_fields : 9; unsigned long num_rows = (unsigned long)st.get_affected_rows(); cout << "rows: " << num_rows << endl; for (size_t i = 0; i < num_fields; ++i) { const soci::column_properties &props = v.get_properties(i); cout << props.get_name() << '\t'; } cout << endl; do { stringstream ss; for (size_t i = 0; i < num_fields; ++i) { if (v.get_indicator(i) == soci::i_null) { ss << "NULL"; break; } const soci::column_properties &props = v.get_properties(i); switch (props.get_data_type()) { case soci::dt_string: ss << v.get<string>(i); break; case soci::dt_double: ss << v.get<double>(i); break; case soci::dt_integer: ss << v.get<int>(i); break; case soci::dt_long_long: ss << v.get<long long>(i); break; case soci::dt_unsigned_long_long: ss << v.get<unsigned long long>(i); break; case soci::dt_date: tm dt = v.get<tm>(i); ss << asctime(&dt); break; } ss << '\t'; } cout << ss.str() << endl; } while (st.fetch()); } catch (soci::soci_error &e) { cerr << "Error: " << e.what() << endl; } return 0; } |
Updated Apr 20, 2015:
1. Under RHEL5/CentOS5, I got errors like:
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./test_oracle: error while loading shared libraries: /home/gonwan/oracle11_64/lib/libnnz11.so: cannot restore segment prot after reloc: Permission denied |
It’s due to SELinux security feature. Simply workaround it with:
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# chcon -t texrel_shlib_t *.so* |
2. Oracle uses oraociei11.dll or libociei.so for client data. They are both large files(110+MB), since they support multiple languages. Instead, you can use oraociicus11.dll(30+MB) or libociicus.so(10-MB). These files contain only English support.