关于python3调用C/C++的方法（ctypes)

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     源代码
     最近帮同事做一个历史数据的转换合并软件，使用python3从数据库读出数据，然后根据其中的几个字段相同的归类合并一行，然后输出到EXCEL中，数据大概是5W行，考虑到归类合并逻辑比较复杂，用python效率比较低，这部分用c/c++完成，python3调用生成的dll.
运行截图

 
 代码如下：
python3代码如下：

# -*- coding: utf-8 -*-'''Created on 2015年8月25日@author: mikewolfli'''from tkinter import *from tkinter import filedialogfrom tkinter import messageboximport psycopg2import ctypesfrom ctypes import py_objectfrom openpyxl import Workbook  import openpyxl.writer.excel as excel_xlsxlib=ctypes.cdll.LoadLibrary("./libdeal_res")lib.combine_list.restype=py_object   #combine_list参数是数据库读取的嵌套list[list,list,list...],
#返回list[list,list....]. 一定要有此行返回参数定义，否则print后显示的结果是整数
xls_header=["梯型","计划设计交单期","四位合同号","WBS项目号","合同名称","梯号","配置工程师","交付项目文档\n项目开始","项目分配","备注","BOM ransfer和项目release","配置完成刷新ID","梯数"]class Application(Frame):    def __init__(self, master=None):        Frame.__init__(self, master)        self.pack()        self.createWidgets()        try:            self.conn=psycopg2.connect(database="pgworkflow", user="postgres", password="1q2w3e4r", host="10.127.144.62", port="5432")        except :            messagebox.showerror(title="连接错误", message="无法连接")            sys.exit()        #self.cur = self.conn.cursor()            def quit_func(self):        if self.conn is not None:            self.conn.close()        self.quit()            def save_file(self):        file_str=filedialog.asksaveasfilename(title="导出文件", initialfile="d:/temp.xlsx",filetypes=[('excel file','.xlsx')])        if not file_str.endswith(".xlsx"):            file_str+=".xlsx"        self.file_string.set(file_str)        def get_old_data(self):        #cur_his=self.conn.cursor(cursor_factory=extras.DictCursor)        cur_his=self.conn.cursor()        cur_his.execute("select * from v_history_units_data order by wbs_no asc;")        #cur_his.execute("select * from client_version")        #col_names = [cn[0] for cn in cur_his.description]        rows_his = cur_his.fetchall()          #print(len(rows_his))        self.rows_lib= lib.combine_list(ctypes.py_object(rows_his))#通过ctypes.py_object转换list为
#c类型的PyObject*                 def export_file(self):        if self.file_string.get()=="":            messagebox.showerror("错误","未指定输出文件")            return                self.get_old_data()                wb=Workbook()        ws=wb.worksheets[0]                for i in range(0,13):            ws.cell(row=1,column=i+1).value=xls_header[i]                  i_row=2          for row in self.rows_lib:            for j in range(0,13):                ws.cell(row=i_row, column=j+1).value=row[j]            i_row=i_row+1                            if excel_xlsx.save_workbook(workbook=wb, filename=self.file_string.get()):            messagebox.showinfo("输出","成功输出!")                                   def createWidgets(self):        self.path_label=Label(self)        self.path_label["text"]="文件"        self.path_label.grid(row=0, column=0)                self.file_string=StringVar()        self.path_entry=Entry(self, textvariable=self.file_string)        self.path_entry["width"]=50        self.path_entry.grid(row=0, column=1, columnspan=2)        self.path_entry["state"]="readonly"                self.path_button=Button(self)        self.path_button["text"]="变更文件"        self.path_button.grid(row=0, column=3)        self.path_button["command"]=self.save_file                self.export_button=Button(self)        self.export_button["text"]="导出数据"        self.export_button.grid(row=1, column=0)        self.export_button["command"]=self.export_file                        self.quit_button=Button(self)        self.quit_button["text"]="退出"        self.quit_button.grid(row=1, column=3)        self.quit_button["command"]=self.quit_func                        if __name__ == '__main__':    root=Tk()    Application(root)    root.title("历史数据导出程序")    #root.geometry('640x360')  #设置了主窗口的初始大小640x360      root.mainloop()    root.destroy()

c/c++代码如下：
main.cpp

// The functions contained in this file are pretty dummy// and are included only as a placeholder. Nevertheless,// they *will* get included in the shared library if you// don't remove them :)//// Obviously, you 'll have to write yourself the super-duper// functions to include in the resulting library...// Also, it's not necessary to write every function in this file.// Feel free to add more files in this project. They will be// included in the resulting library.#include <Python.h>#include <stdio.h>#include <string.h>#include <errno.h>#include <stdlib.h>#include <windows.h>#include "py2cpp.hpp"using namespace std;using namespace dubzzz::Py2Cpp;struct  data_row{    string lift_type;    string plan_design_finish;    string contract_id;    string project_id;    string project_name;    string lift_id;    string res_engineer;    string act_design_finish;    string prj_distribution;    string remarks;    string bom_trans_rel;    string refresh_id;    int lift_num;    data_row & operator=(const data_row &other);};
data_row & data_row::operator=(const data_row &other){    if(&other!=this)    {        lift_type = other.lift_type;        plan_design_finish = other.plan_design_finish;        contract_id=other.contract_id;        project_id = other.project_id;        project_name = other.project_name;        lift_id = other.lift_id;        res_engineer=other.res_engineer;        act_design_finish = other.act_design_finish;        prj_distribution = other.prj_distribution;        remarks = other.remarks;        bom_trans_rel = other.bom_trans_rel;        refresh_id=other.refresh_id;        lift_num = other.lift_num;    }
    return *this;
};PyObject* topyfromstruct(data_row & row){//MessageBox(NULL,"test", "对话框（标题）", MB_OK);     return Py_BuildValue("(s, s, s,s,s,s,s,s,s,s,s,s,i)",row.lift_type.c_str(),row.plan_design_finish.c_str(), row.contract_id.c_str(),\                          row.project_id.c_str(),row.project_name.c_str(),row.lift_id.c_str(),row.res_engineer.c_str(),row.act_design_finish.c_str(),\                          row.prj_distribution.c_str(),row.remarks.c_str(),row.bom_trans_rel.c_str(),row.refresh_id.c_str(),row.lift_num);};PyObject* topyfromvector(vector<data_row> & rows){    vector<data_row>::iterator  it;    PyObject* pylist=PyList_New(rows.size());    Py_ssize_t i_pos=0;    for(it=rows.begin();it!=rows.end();it++,i_pos++)    {        PyList_SetItem(pylist,i_pos, topyfromstruct(*it));    }    //MessageBox(NULL, rows[0].project_id.c_str(), "对话框（标题）", MB_OK);    return pylist;}data_row tocppfromtuple(PyObject* pyo){    assert(pyo);    data_row  row;    Py_ssize_t i_size=12;    if (PyTuple_Check(pyo))    {      if (PyTuple_Size(pyo) == 12)      {          PyObject * py0=PyTuple_GetItem(pyo,0);          if(py0==Py_None)              row.lift_type="";          else             row.lift_type = CppBuilder<string>()(py0) ;          PyObject * py1=PyTuple_GetItem(pyo, 1);          if(py1==Py_None)            row.plan_design_finish="";          else          {             row.plan_design_finish =  CppBuilder<string>()(py1) ;          }          PyObject * py2 = PyTuple_GetItem(pyo, 2);          if(py2==Py_None)              row.contract_id="";          else          {             row.contract_id = CppBuilder<string>()(py2)  ;          }          PyObject *py3 = PyTuple_GetItem(pyo, 3);          if(py3==Py_None)               row.project_id="";          else          {              row.project_id = CppBuilder<string>()(py3) ;          }          PyObject *py4 = PyTuple_GetItem(pyo, 4);          if(py4==Py_None)               row.project_name ="";          else          {              row.project_name = CppBuilder<string>()(py4) ;          }          PyObject *py5 = PyTuple_GetItem(pyo, 5);          if(py5==Py_None)            row.lift_id="";          else          {              row.lift_id = CppBuilder<string>()(py5) ;          }          PyObject* py6 = PyTuple_GetItem(pyo, 6);          if(py6==Py_None)              row.res_engineer="";          else          {              row.res_engineer = CppBuilder<string>()(py6) ;          }          //MessageBox(NULL,row.plan_design_finish.c_str(),"对话框（标题）", MB_OK);          PyObject * py7 = PyTuple_GetItem(pyo,7);          if(py7==Py_None)              row.act_design_finish="";          else              row.act_design_finish = CppBuilder<string> ()(py7);         PyObject * py8 = PyTuple_GetItem(pyo,8);         if(py8==Py_None)            row.prj_distribution="";         else             row.prj_distribution = CppBuilder<string> ()(py8) ;         PyObject *py9 = PyTuple_GetItem(pyo, 9);         if(py9==Py_None)             row.remarks = "";         else              row.remarks =CppBuilder<string> ()(py9) ;        PyObject *py10 = PyTuple_GetItem(pyo, 10);        if(py10==Py_None)            row.bom_trans_rel="";        else           row.bom_trans_rel = CppBuilder<string>()(py10);         row.lift_num = 1;         return row;      }      else      {        ostringstream oss;        oss << "PyTuple length differs from required one: "            << "PyTuple(" << PyTuple_Size(pyo) << ") "            << "and required( %d" <<i_size << ")";        throw length_error(oss.str());      }    }    throw invalid_argument("Not a PyTuple instance");}vector<data_row> tocppfromlist(PyObject * pyo){    assert(pyo);    if(PyList_Check(pyo))    {       vector<data_row> rows;       data_row row;       Py_ssize_t i_rows= PyList_Size(pyo);      for(Py_ssize_t i=0;i<i_rows;i++)      {      //     MessageBox(NULL, "test", "对话框（标题）", MB_OK);           row = tocppfromtuple(PyList_GetItem(pyo, i));           rows.push_back(row);      }      //MessageBox(NULL, rows[0].project_id.c_str(), "对话框（标题）", MB_OK);       return rows;    }   throw invalid_argument("Not a PyList instance");}
vector<data_row> combine_the_same_section(vector<data_row> &rows){    vector<data_row> drv_res;    data_row dr_base;    size_t i_count = rows.size();    dr_base=rows[0];    int i_units=1;    string s_refresh_id;    for(size_t i=1;i<i_count;i++)    {        if(dr_base.project_id==rows[i].project_id&&dr_base.lift_type==rows[i].lift_type&&dr_base.plan_design_finish==rows[i].plan_design_finish&&           dr_base.res_engineer==rows[i].res_engineer&&dr_base.act_design_finish==rows[i].act_design_finish&&dr_base.prj_distribution==rows[i].prj_distribution&&           dr_base.bom_trans_rel==rows[i].bom_trans_rel)        {           dr_base.lift_id=dr_base.lift_id+","+rows[i].lift_id;           i_units++;        }else        {            dr_base.refresh_id=dr_base.contract_id+":"+dr_base.project_id+":"+dr_base.project_name+":"+dr_base.lift_id;            dr_base.lift_num=i_units;            drv_res.push_back(dr_base);            dr_base=rows[i];            i_units=1;        }    }    rows.clear();    return drv_res;}extern "C"{    // A function adding two integers and returning the result    PyObject * combine_list( PyObject * pyo)    {        assert(pyo);        PyObject *py_res;        vector<data_row> drv_temp =tocppfromlist(pyo);        vector<data_row> drv_res=combine_the_same_section(drv_temp);      // MessageBox(NULL, drv_res[0].lift_id.c_str(), "对话框（标题）", MB_OK);        py_res = topyfromvector(drv_res);        drv_res.clear();        return py_res;    }}

py2cpp.hpp参照https://github.com/dubzzz/Py2Cpp 此项目更改，代码如下，在string转换中增加datetime的转换。
另外如要转换为time_t,需增加到long下面，因为单独加time_t时会报错，long重复定义。
另： Int在python3中已经统一由long代替，故在PyInt_** 全部加入python版本判断。

#ifndef __PY2CPP_HPP__#define __PY2CPP_HPP__#include <cassert>#include <climits>#include <sstream>#include <stdexcept>#include <typeinfo>#include <map>#include <set>#include <string>#include <tuple>#include <ctime>#include <vector>#include <Python.h>#include <datetime.h>namespace dubzzz {namespace Py2Cpp {template <class T>struct CppBuilder;template <>struct CppBuilder<PyObject*>{  PyObject* operator() (PyObject* pyo)  {    assert(pyo);    return pyo;  }};template <>struct CppBuilder<bool>{  bool operator() (PyObject* pyo)  {    assert(pyo);    if (PyBool_Check(pyo))    {      return pyo == Py_True;    }    throw std::invalid_argument("Not a PyBool instance");  }};template <>struct CppBuilder<int>{  int operator() (PyObject* pyo)  {    assert(pyo);    if (PyLong_Check(pyo))    {      long v { PyLong_AsLong(pyo) };      if (v < INT_MIN || v > INT_MAX)      {        throw std::overflow_error("Out of <int> boundaries");      }      return static_cast<int>(v);    }#if PY_MAJOR_VERSION <=2    else if (PyInt_Check(pyo))    {      long v { PyInt_AS_LONG(pyo) };      if (v < INT_MIN || v > INT_MAX)      {        throw std::overflow_error("Out of <int> boundaries");      }      return static_cast<int>(v);    }#endif // PY_MAJOR_VERSION    throw std::invalid_argument("Not a PyLong instance");  }};template <>struct CppBuilder<unsigned int>{  unsigned int operator() (PyObject* pyo)  {    assert(pyo);    if (PyLong_Check(pyo))    {      unsigned long v { PyLong_AsUnsignedLongMask(pyo) };      if (v > UINT_MAX)      {        throw std::overflow_error("Out of <unsigned int> boundaries");      }      return static_cast<unsigned int>(v);    }#if PY_MAJOR_VERSION <=2    else if (PyInt_Check(pyo))    {      unsigned long v { PyInt_AsUnsignedLongMask(pyo) };      if (v > UINT_MAX)      {        throw std::overflow_error("Out of <unsigned int> boundaries");      }      return static_cast<int>(v);    }#endif // PY_MAJOR_VERSION    throw std::invalid_argument("Not a PyLong instance");  }};template <>struct CppBuilder<long>{  long operator() (PyObject* pyo)  {    assert(pyo);    if (PyLong_Check(pyo))    {      return PyLong_AsLong(pyo);    }#if PY_MAJOR_VERSION <=2    else if (PyInt_Check(pyo))    {      return PyInt_AS_LONG(pyo);    }#endif // PY_MAJOR_VERSION   /* else  if(PyDate_Check(pyo))    {            struct tm tim;            tim.tm_year = PyDateTime_GET_YEAR(pyo) ;            tim.tm_mon = PyDateTime_GET_MONTH(pyo) ;            tim.tm_mday = PyDateTime_GET_DAY(pyo) ;            std::time_t date_res= mktime(&tim);            return date_res;    }*/    throw std::invalid_argument("Not a PyLong instance");  }};template <>struct CppBuilder<unsigned long>{  unsigned long operator() (PyObject* pyo)  {    assert(pyo);    if (PyLong_Check(pyo))    {      return PyLong_AsUnsignedLong(pyo);    }#if PY_MAJOR_VERSION <=2    else if (PyInt_Check(pyo))    {      return PyInt_AsUnsignedLongMask(pyo);    }#endif // PY_MAJOR_VERSION    throw std::invalid_argument("Not a PyLong instance");  }};template <>struct CppBuilder<long long>{  long long operator() (PyObject* pyo)  {    assert(pyo);    if (PyLong_Check(pyo))    {      return PyLong_AsLongLong(pyo);    }#if PY_MAJOR_VERSION <=2    else if (PyInt_Check(pyo))    {      return PyInt_AS_LONG(pyo);    }#endif // PY_MAJOR_VERSION    throw std::invalid_argument("Not a PyLong instance");  }};template <>struct CppBuilder<unsigned long long>{  unsigned long long operator() (PyObject* pyo)  {    assert(pyo);    if (PyLong_Check(pyo))    {      return PyLong_AsUnsignedLongLong(pyo);    }#if PY_MAJOR_VERSION <=2    else if (PyInt_Check(pyo))    {      return PyInt_AsUnsignedLongLongMask(pyo);    }#endif // PY_MAJOR_VERSION    throw std::invalid_argument("Not a PyLong instance");  }};template <>struct CppBuilder<double>{  double operator() (PyObject* pyo)  {    assert(pyo);    if (PyFloat_Check(pyo))    {      return PyFloat_AS_DOUBLE(pyo);    }    else if (PyLong_Check(pyo))    {      return PyLong_AsDouble(pyo);    }#if PY_MAJOR_VERSION <=2    else if (PyInt_Check(pyo))    {      return PyInt_AS_LONG(pyo);    }#endif // PY_MAJOR_VERSION    throw std::invalid_argument("Neither a PyDouble nor a PyLong instance");  }};template <>struct CppBuilder<std::string>{  std::string operator() (PyObject* pyo)  {    assert(pyo);    if (PyUnicode_Check(pyo))    {
       if(pyo==Py_None)
           return "";
#if PY_MAJOR_VERSION >=3 and PY_MINOR_VERSION >=3      Py_ssize_t size;      const char* str { PyUnicode_AsUTF8AndSize(pyo, &size) };#else      long unsigned int size { PyUnicode_GET_DATA_SIZE(pyo) }; // depreciated since 3.3      const char* str { PyUnicode_AS_DATA(pyo) }; // depreciated since 3.3#endif      return std::string(str, size);    }else    //if(PyDate_Check(pyo)||PyDateTime_Check(pyo) )    {        int i_year {PyDateTime_GET_YEAR(pyo) };        int i_month { PyDateTime_GET_MONTH(pyo) } ;        int i_day  { PyDateTime_GET_DAY(pyo) };        char s_date[16];        sprintf(s_date, "%d-%d-%d", i_year,i_month,i_day);        //MessageBox(NULL, s_date, "对话框（标题）", MB_OK);        return std::string(s_date);    }    //throw std::invalid_argument("Not a PyUnicode or PyDateTime instance");  }};template <class TUPLE, std::size_t pos>void _feedCppTuple(TUPLE& tuple, PyObject* root){}template <class TUPLE, std::size_t pos, class T, class... Args>void _feedCppTuple(TUPLE& tuple, PyObject* root){  std::get<pos>(tuple) = CppBuilder<T>()(PyTuple_GetItem(root, pos));  _feedCppTuple<TUPLE, pos +1, Args...>(tuple, root);}template <class... Args>struct CppBuilder<std::tuple<Args...>>{  std::tuple<Args...> operator() (PyObject* pyo)  {    assert(pyo);    if (PyTuple_Check(pyo))    {      if (PyTuple_Size(pyo) == sizeof...(Args))      {        std::tuple<Args...> tuple { std::make_tuple(Args()...) };        _feedCppTuple<std::tuple<Args...>, 0, Args...>(tuple, pyo);        return tuple;      }      else      {        std::ostringstream oss;        oss << "PyTuple length differs from asked one: "            << "PyTuple(" << PyTuple_Size(pyo) << ") "            << "and std::tuple<...>(" << sizeof...(Args) << ")";        throw std::length_error(oss.str());      }    }    throw std::invalid_argument("Not a PyTuple instance");  }};/** * VECTOR has to have the following characteristics: * * (constructor): *    VECTOR(size_type count) *    build a VECTOR of size count * * ::begin() * ::end() * ::iterator compatible with ++it */template <class VECTOR>struct CppBuilder{  VECTOR operator() (PyObject* pyo)  {    assert(pyo);    if (PyList_Check(pyo))    {      unsigned int i { 0 };      VECTOR v(PyList_Size(pyo));      for (typename VECTOR::iterator it { v.begin() } ; it != v.end() ; ++it, ++i)      {        *it = CppBuilder<typename VECTOR::value_type>()(PyList_GetItem(pyo, i));      }      return v;    }    throw std::invalid_argument("Not a PyList instance");  }};template <class T>struct CppBuilder<std::set<T>>{  std::set<T> operator() (PyObject* pyo)  {    assert(pyo);    if (PySet_Check(pyo))    {      long size { PySet_Size(pyo) };      std::vector<PyObject*> backup(size);      std::set<T> s;      for (long i { 0 } ; i != size ; ++i)      {        PyObject* popped { PySet_Pop(pyo) };        backup[i] = popped;        s.insert(CppBuilder<T>()(popped));      }      for (PyObject* popped : backup)      {        PySet_Add(pyo, popped);        Py_DECREF(popped);      }      return s;    }    throw std::invalid_argument("Not a PySet instance");  }};template <class K, class T>struct CppBuilder<std::map<K,T>>{  std::map<K,T> operator() (PyObject* pyo)  {    assert(pyo);    if (PyDict_Check(pyo))    {      std::map<K,T> dict;      PyObject *key, *value;      Py_ssize_t pos = 0;      while (PyDict_Next(pyo, &pos, &key, &value))      {        dict[CppBuilder<K>()(key)] = CppBuilder<T>()(value);      }      return dict;    }    throw std::invalid_argument("Not a PyDict instance");  }};}}#endif
项目地址： https://github.com/mikewolfli/history_data