cpp
C++のTips
| Table of Contents |
int isdigit(int c)
bool isdigit(文字) の引数は 0 ～ 255 (unsigned char) と -1 (EOF)。
- 1 も受け取れるように unsigned char ではなく int が引数となっている。
char と unsigned char の違い
unsigned char uc = 255;
char c = uc; // char は -128 - 127
printf("%d %d\n", uc, c); // 255 -1 (どちらも 0xff には違いない)
printf("%c %c\n", uc, c); // なんという字かはわからないが同じもの
16進数として同じなら、unsinged でも singed でも同じ文字を意味する。
fatal_error
/*
fatal_error() prints the error message contained in format then exits with
exit code 1.
*/
void fatal_error(char* format, ...)
{
va_list ap; // format argument list
fprintf( stderr, "Error: ");
// assemble argument list and print format using it
va_start( ap, format );
vfprintf( stderr, format, ap );
va_end(ap);
fprintf( stderr, "\n");
exit(1);
}
MIN/MAX/ABS
#ifndef MIN #define MIN(x,y) ( ( x < y )? x : y ) #endif #ifndef MAX #define MAX(x,y) ( ( x > y )? x : y ) #endif #ifndef ABS #define ABS(x) ( ( x < 0 )? -x : x ) #endif
std::min だったり、そもそもなかったり。 abs は fabs だったりするため。
M_PI
#define _USE_MATH_DEFINES #include <math.h>
FLT_MAX/DBL_MAX
#include <float.h>
INT_MAX
#include <limits.h>
ファイル一覧
Windows
_findfirst(*.txt), _findnext
linux
glob(*.txt)
#ifdef platform
#if defined(_WIN32) || defined(_WIN64) #elif #else #endif
* メモ
o プリプロセッサは、未定義の識別子を0として扱う。
o 従って、#if __GNUC__ >= 3はGCC3以上として使えるが、GCC2系かどうかを#if __GNUC__ < 3で判定しようとすると、GCCでないものも含まれるので注意が必要。
* コンパイラ
o GCCかどうか
#ifdef __GNUC__
+ #if __GNUC__ >= 3 // GCC3.0以上
o Visual C++かどうか
#ifdef _MSC_VER（VC++以外でも定義されている場合あり）
+ #if _MSC_VER >=1000 // VC++4.0以降
+ #if _MSC_VER >=1100 // VC++5.0以降
+ #if _MSC_VER >=1200 // VC++6.0以降
+ #if _MSC_VER >=1300 // VC2003以降
+ #if _MSC_VER >=1400 // VC2005以降
o Borland C++かどうか
#ifdef __BORLANDC__
* UNIX
o UNIXかどうか
#ifdef __unix
or
#ifdef __unix__
o Linuxかどうか
#ifdef __linux
or
#ifdef __linux__
o FreeBSDかどうか
#ifdef __FreeBSD__
o NetBSDかどうか
#ifdef __NetBSD__
* Windows
o 32bitかどうか
#ifdef _WIN32（これはよく使う、WIN32でもよい）
o 64bitかどうか
#ifdef _WIN64
o GUIアプリかどうか
#ifdef _WINDOWS
o CUIアプリかどうか
#ifdef _CONSOLE
o Windowsのバージョン … WINVER
※ PC向けWindows（95/98/Me/NT/2000/XP/Vista）とWindows CEの両方で定義される
+ #if (WINVER >= 0x030a) // Windows 3.1以降
+ #if (WINVER >= 0x0400) // Windows 95/NT4.0以降
+ #if (WINVER >= 0x0410) // Windows 98以降
+ #if (WINVER >= 0x0500) // Windows Me/2000以降
+ #if (WINVER >= 0x0501) // Windows XP以降
+ #if (WINVER >= 0x0600) // Windows Vista以降
o Windows 95/98/Meのバージョン … _WIN32_WINDOWS
+ MFCアプリケーションで、PC向けWindowsかどうか（Windows CEでは定義されないため）
#ifdef _WIN32_WINDOWS
+ #if (_WIN32_WINDOWS >= 0x0400) // Windows 95以降
+ #if (_WIN32_WINDOWS >= 0x0410) // Windows 98以降
+ #if (_WIN32_WINDOWS >= 0x0500) // Windows Me以降
o Windows NTのバージョン … _WIN32_WINNT
+ #if (_WIN32_WINNT >= 0x0500) // Windows 2000以降
+ #if (_WIN32_WINNT >= 0x0501) // Windows XP以降
+ #if (_WIN32_WINNT >= 0x0600) // Windows Vista以降
o Windows CE（PocketPC）かどうか
#ifdef _WIN32_WCE
o Windows CEのバージョン … WINCEOSVER
o Windows CEなら以下実行
WCE_IF(CEのとき, 非CEのとき)
o Internet Explorerのバージョン … _WIN32_IE
* Cygwin
o Cygwinかどうか
#ifdef __CYGWIN__
o 32bit版Cygwinかどうか（64bit版はまだないが）
#ifdef __CYGWIN32__
o MinGW（-mno-cygwin指定）かどうか
#ifdef __MINGW32__
reference
- http://d.hatena.ne.jp/firewood/20050601
- http://alxr.usatlas.bnl.gov/lxr/source/external/boost-1_34_1/boost/config/select_platform_config.hpp?v=head
- http://predef.sourceforge.net/
class 定義時のカンマを忘れるな
class Test{
};
コンストラクタの再利用はできない。
class Test{
public:
int num;
Test(int i){
num=i;
}
Test(){
Test(10);
//ここで結局値がなくなる。
}
};
可変引数
#include <stdio.h>
#include <stdarg.h>
int sprintf(char *s, const char *format, ...)
{
va_list ap;
int result;
va_start(ap, format);
result = vsprintf(s, format, ap);
va_end(ap);
return result;
}
可変長引数の仮引数は格上げされてしまう。
int arg = va_arg(ap, int); char, short --> int float --> double
format を解析して、次は double のはずだ、と va_arg(ap, double) にしたり、 %s なら、\0 まで読み込んで文字列にしたりする？いや、 char* が渡されるのかな？ va_arg(ap, char*);
つまり、va_arg(ap, string) とかはできないのか？&string で渡してやれば string* で受け取ったりできないのかな？
http://program.station.ez-net.jp/special/vc/basic/function/stdarg.asp
Simple Sudo
Infinite length of arguments, chmod +s
Compile this as root user. Then,
chmod +s a.out
as root user. All users can execute any commands with root privilege as
./a.out rm -rf /
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
int main(int argc, char **argv) {
char *com;
int size = 1024;
int i;
com = malloc(size);
for(i = 1; i < argc; i++) {
if(strlen(com) + strlen(argv[i]) > size) {
size *= 2;
com = realloc(com, size);
}
strcat(com, "\"");
strcat(com, argv[i]);
strcat(com, "\"");
strcat(com, " ");
}
//real user id, getuid() -> real user
//effective user id, geteuid() -> s-bit user
setreuid(geteuid(),geteuid());
setregid(getegid(),getegid());
//execvp(argv[1],&argv[2]); // if argc == 1,,,,
system(com);
free(com);
return(1);
}
Network
client on windows
/////////////////////////////////////////////////////////////////////////////
// client.cpp
// client side program on Windows
//
// Naotoshi Seo masc0990, Sep 21 2005
// Last modified: Sep 22 2005
//
// This program is a practice for implementation of client side program
// on Windows. This client requests two integers input for user and
// sends message to server and receives the addition of those two from server.
/////////////////////////////////////////////////////////////////////////////
#include <windows.h>
#include <stdlib.h>
#include <stdio.h>
#include <iostream.h>
#include <time.h>
#include <winsock.h>
//#define DEST_IP "127.0.0.1" // Loopback connection to the local machine
#define DEST_IP "130.191.3.100" // rohan.sdsu.edu
#define PORT 9990 // Port number
#define NO_FLAGS_SET 0 // No flag for send and recv function
int main()
{
int m;
//Initialize the dll for socket API
WSADATA wdata;
int wstatus = WSAStartup(MAKEWORD(1,1), &wdata);
if (wstatus != 0) // error occurs
{
cout << "Client failed to initialize winsock." << endl;
exit(1);
}
else
{
cout << "Client successfully initialized winsock." << endl;
}
SOCKADDR_IN ca; // Client socket address structure
ca.sin_family = AF_INET; // TCP Protocol
ca.sin_port = htons(PORT); // Supply the port number
ca.sin_addr.s_addr = inet_addr(DEST_IP); // Destination IP address
SOCKET cs = socket( // Create socket
AF_INET, // Internet address family (
SOCK_STREAM, // Connection-oriented (stream) socket type
// which uses TCP packets (reliable, duplex)
// Can also be: SOCK_DGRAM - uses UDP packets
0); // Protocol (0 - system picks approp. protocol
// Returns client's socket descriptor (cs)
if(cs == INVALID_SOCKET) // error
{
cout << "Client failed to create a socket. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else
{
cout << "Client successfully created a socket. " << endl;
}
m = connect( // Request connection with the server
cs, // Client's socket (returned by socket())
(LPSOCKADDR)&ca, // Pointer to the server's socket address str.
sizeof(ca)); // Length of the address structure
// Returns 0 (no error) or SOCKET_ERROR
if (m == SOCKET_ERROR) // error
{
cout << "Client failed to connect." << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else if (m == 0)
{
cout << "Client successfully connected with server, " << DEST_IP << ":" << PORT << endl;
}
int in1, in2;
char input[256];
char tmp[256];
char msg[256];
while(1)
{
cout << "Please enter two integers" << endl;
gets(input); // retrive inputs from user
cout << "[Input] " << input << endl;
if (sscanf(input, "%d %d%s", &in1, &in2, tmp) == 2)
// Two valid numbers are entered
// Memo: Thanks to last tmp, it can reject e.g. 5 5.6, 4 5 6 also.
{
// construct message
sprintf(msg, "Please add the follwing two numbers for me: %d and %d",in1,in2);
m = send(cs, msg, strlen(msg)+1, NO_FLAGS_SET); // Send message to server
if (m == SOCKET_ERROR) // error occurs
{
cout << "Client failed to send message. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Client successfully sent message. " << endl;
cout << "[Sent] " << msg << endl;
}
m = recv(cs, msg, sizeof(msg), NO_FLAGS_SET); // Wait message from server
if (m == SOCKET_ERROR) // error occurs
{
cout << "Client failed to receive message. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Client successfully received message. " << endl;
cout << "[Received] " << msg << endl;
}
}
else
{ // Invalid numbers // Terminate the loop
strcpy(msg,input);
send(cs, msg, strlen(msg)+1, NO_FLAGS_SET); // Send message to server
if (m == SOCKET_ERROR) // error occurs
{
cout << "Client failed to send message for termination. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Client successfully sent message. " << endl;
cout << "[Sent] " << msg << endl;
}
recv(cs, msg, sizeof(msg), NO_FLAGS_SET); // Wait message from server
if (m == SOCKET_ERROR) // error occurs
{
cout << "Client failed to receive message for termination. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Client successfully received message. " << endl;
cout << "[Received] " << msg << endl;
}
break; // Terminate the loop
}
}
m = closesocket(cs); // Release the socket descriptor cs
// and delete all underlying structures
// (address info, queue and queued requests
// if any.)
// Returns 0 (success) or SOCKET_ERROR
if (m == SOCKET_ERROR)
{
cout << "Client failed to close connection. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else if (m == 0)
{
cout << "Client successfully closed connection." << endl;
}
wstatus = WSACleanup(); // Cleanup socket API
if (wstatus != 0)
{
cout << "Client failed to cleanup winsock. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else
{
cout << "Client successfully cleaned winsock up." << endl;
}
return 0;
}
server on windows
///////////////////////////////////////////////////////////////////////////
// server.cpp
// Multi threading server on Windows
//
// Naotoshi Seo masc0990, Sep 21 2005
// Last modified: Sep 22 2005
//
// This program is a practice for implementation of server side program
// on Windows. This has multi threading function. This server receives two
// integers from a client and sends addition of those two to the client.
/////////////////////////////////////////////////////////////////////////////
#include <windows.h>
#include <stdlib.h>
#include <stdio.h>
#include <iostream.h>
#include <time.h>
#include <winsock.h>
#include <string.h>
#define PORT 9990 // Port number
#define NO_FLAGS_SET 0 // No flag for send and recv function
#define MAX_CONNECTION 100
// Server creates this thread to serve a client
// return: nothing
// parameter: pointer of socket descripter.
void ClientThread(void *csock)
{
int m;
char msg[256];
char msg_template[] = "Please add the follwing two numbers for me: ";
char tmp[256];
int in1, in2;
SOCKET* cs = (SOCKET*)csock;
while(1) // Infinite loop
{
m = recv(*cs, msg, sizeof(msg), NO_FLAGS_SET); // Wait for a message from the client
if (m == SOCKET_ERROR) // error occurs
{
cout << "Server failed to receive message. Client ID: " << *cs << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Server successfully received message. Client ID: " << *cs << endl;
cout << "[Received] " << msg << endl;
}
// Extract numbers from message
if(strncmp(msg, msg_template, sizeof(msg_template)-1) == 0 &&
sscanf(&msg[sizeof(msg_template)-1], "%d%s%d%s" ,&in1, tmp, &in2, tmp) == 3)
{
// the numbers are valid integers
sprintf(msg, "The sum of your numbers is: %d", in1 + in2);
m = send(*cs, msg, strlen(msg)+1, NO_FLAGS_SET); // Send message to the client
if (m == SOCKET_ERROR) // error occurs
{
cout << "Server failed to send message. Client ID: " << *cs << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Server successfully sent message. Client ID: " << *cs << endl;
cout << "[Sent] " << msg << endl;
}
}
else // Invalid numbers
{
strcpy(msg, "We appreciated the business with you, bye\0");
m = send(*cs, msg, strlen(msg)+1, NO_FLAGS_SET); // Send message to the client
if (m == SOCKET_ERROR) // error occurs
{
cout << "Server failed to send termination message. Client ID: " << *cs << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Server successfully sent message. Client ID: " << *cs << endl;
cout << "[Sent] " << msg << endl;
}
break; // Terminate the loop
}
}
m = closesocket(*cs); // Release the socket descriptor cs
// and delete all underlying structures
// (address info, queue and queued requests
// if any.)
// Returns 0 or SOCKET_ERROR
if (m == SOCKET_ERROR)
{
cout << "Server failed to close connection. Client ID: " << *cs << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else if (m == 0)
{
cout << "Server successfully closed connection. Client ID: " << *cs << endl;
}
} // End of client therad
int main() // The primary thread of the server
{
int m;
//Initialize the dll for socket API
WSADATA wdata;
int wstatus = WSAStartup(MAKEWORD(1,1), &wdata);
if (wstatus != 0) {
cout << "Failed to initialize winsock. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
SOCKET s = socket( // Create socket
AF_INET, // Internet address family
SOCK_STREAM, // Connection-oriented (stream) socket type
// which uses TCP packets (reliable, duplex)
// Can also be: SOCK_DGRAM - uses UDP packets
// (see chapter 10)
0); // Protocol (0 - system picks approp. protocol
// Returns socket descriptor (s)
if(s == INVALID_SOCKET)
{
cout << "Server failed to create a socket. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else
{
cout << "Server successfully created a socket. " << endl;
}
SOCKADDR_IN sa; // Server socket address structure
sa.sin_family = AF_INET; // TCP Protocol
sa.sin_port = htons(PORT); // Supply the port number
sa.sin_addr.s_addr = htonl(INADDR_ANY);
m = bind( // Associate the local address with the socket
s, // Socket descriptor (returned by socket())
(LPSOCKADDR)&sa, // Pointer to the socket address structure
sizeof(sa)); // Length of the address structure
if (m == SOCKET_ERROR)
{
cout << "Server failed to bind. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else if (m == 0)
{
cout << "Server successfully binded." << endl;
}
m = listen( // Allow socket to take connections
s, // Socket descriptor (returned by socket())
MAX_CONNECTION);// Maximal number of requests allowed
if (m == SOCKET_ERROR)
{
cout << "Server failed to listen connection. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else if (m == 0)
{
cout << "Server is listening connection." << endl;
}
SOCKET cs[MAX_CONNECTION];
HANDLE hThread[MAX_CONNECTION];
DWORD dwID[MAX_CONNECTION];
int i;
for(i = 0; i < MAX_CONNECTION; i++) // Connection request loop
{
int length = sizeof(sa);
cs[i] = accept( // Accept a connection from a client
s, // Socket descriptor (returned by socket())
// (s identifies the socket which listens
// and accepts connection requests)
(LPSOCKADDR)&sa,// Socket address structure received from
// connecting entity (client)
&length); // Length of sa
// Returns new socket descriptor (ns)
if(cs[i] == INVALID_SOCKET)
{
cout << "Server failed to accept connection. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Server successfully accepted connection. Client ID: " << cs[i] << endl;
}
// Create Thread
hThread[i] = CreateThread(
NULL, // Pointer to a SECURITY_ATTRIBUTES structure
// that determines whether the returned handle
// can be inherited by child processes.
// If lpThreadAttributes is NULL,
// the handle cannot be inherited.
0, // Initial size of the stack, in bytes.
(LPTHREAD_START_ROUTINE)ClientThread,
// Pointer to the application-defined
//function to be executed by the thread
&cs[i], // Pointer to a variable to be passed to the thread.
0, // Flags that control the creation of the thread.
// If the CREATE_SUSPENDED flag is specified,
// the thread is created in a suspended state,
// and will not run until the ResumeThread
// function is called. If this value is zero,
// the thread runs immediately after creation.
&dwID[i]); // Pointer to a variable that receives the
// thread identifier.
if (hThread == NULL)
{
cout << "Server failed to create a thread. " << endl;
cout << "Error code: " << GetLastError() << endl;
break;
}
else
{
cout << "Server successfully created a thread. Thread ID: " << dwID[i] << endl;
}
}
// Release thread objects (close handles)
for(int j = 0; j < i; j++)
{
m = CloseHandle(hThread[j]);
if(m == 0)
{
cout << "Server failed to release a thread. Thread ID: " << dwID[j] << endl;
cout << "Error code: " << GetLastError() << endl;
}
else
{
cout << "Server successfully released a thread. Thread ID: " << dwID[j] << endl;
}
}
m = closesocket(s); // Release the socket descriptor s
// and delete all underlying structures
// (address info, queue and queued requests
// if any.)
// Returns 0 or SOCKET_ERROR
if (m == SOCKET_ERROR)
{
cout << "Server failed to close server socket. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else if (m == 0)
{
cout << "Server successfully closed server socket." << endl;
}
wstatus = WSACleanup(); // Cleanup socket API
if (wstatus != 0)
{
cout << "Server failed to cleanup winsock. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else
{
cout << "Server successfully cleaned winsock up." << endl;
}
return 0;
}// End of server
server on UNIX
////////////////////////////////////////////////////////////////////////////
// posix_server.c
// Multi threading server on Solaris
//
// Naotoshi Seo masc0990, Sep 22 2005
// Last modified: Sep 22 2005
//
// This program is a practice for implementation of server side program
// on Solaris. This has multi threading function. This server receives two
// integers from a client and sends addition of those two to the client.
//
// Memo: I checked each API error,
// not only check if the API returns nonnegative value.
// I printed out 'errno' which will be stored error code also.
/////////////////////////////////////////////////////////////////////////////
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <stddef.h>
#include <unistd.h>
#include <stdio.h>
#include <iostream.h>
#include <pthread.h>
#include <thread.h>
#define PORT 9990 // Port number
#define NO_FLAGS_SET 0 // No flag for send and recv function
#define MAX_CONNECTION 100
// Cushion to abosorb difference with winsock
#include <errno.h>
#define WSAGetLastError() errno
#define SOCKET int
#define LPSOCKADDR struct sockaddr *
#define SOCKADDR struct sockaddr
#define SOCKADDR_IN sockaddr_in
#define SOCKET_ERROR -1
#define closesocket close
#define INVALID_SOCKET -1
// Server creates this thread to serve a client
// return: 0
// parameter: pointer of socket descripter.
extern "C" void * ClientThread(void *csock)
{
int m;
char msg[256];
char msg_template[] = "Please add the follwing two numbers for me: ";
char tmp[256];
int in1, in2;
SOCKET* cs = (SOCKET*)csock;
while(1) // Infinite loop
{
m = recv(*cs, msg, sizeof(msg), NO_FLAGS_SET); // Wait for a message from the client
if (m == SOCKET_ERROR) // error occurs
{
cout << "Server failed to receive message. Client ID: " << *cs << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Server successfully received message. Client ID: " << *cs << endl;
cout << "[Received] " << msg << endl;
}
// Extract numbers from message
if(strncmp(msg, msg_template, sizeof(msg_template)-1) == 0 &&
sscanf(&msg[sizeof(msg_template)-1], "%d%s%d%s" ,&in1, tmp, &in2, tmp) == 3)
{
// the numbers are valid integers
sprintf(msg, "The sum of your numbers is: %d", in1 + in2);
m = send(*cs, msg, strlen(msg)+1, NO_FLAGS_SET); // Send message to the client
if (m == SOCKET_ERROR) // error occurs
{
cout << "Server failed to send message. Client ID: " << *cs << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Server successfully sent message. Client ID: " << *cs << endl;
cout << "[Sent] " << msg << endl;
}
}
else // Invalid numbers
{
strcpy(msg, "We appreciated the business with you, bye\0");
m = send(*cs, msg, strlen(msg)+1, NO_FLAGS_SET); // Send message to the client
if (m == SOCKET_ERROR) // error occurs
{
cout << "Server failed to send termination message. Client ID: " << *cs << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Server successfully sent message. Client ID: " << *cs << endl;
cout << "[Sent] " << msg << endl;
}
break; // Terminate the loop
}
}
m = closesocket(*cs); // Release the socket descriptor cs
// and delete all underlying structures
// (address info, queue and queued requests
// if any.)
// Returns 0 or SOCKET_ERROR
if (m == SOCKET_ERROR)
{
cout << "Server failed to close connection. Client ID: " << *cs << endl;
cout << "Error code: " << WSAGetLastError() << endl;
pthread_exit((void *)1);
}
else if (m == 0)
{
cout << "Server successfully closed connection. Client ID: " << *cs << endl;
}
return 0;
//Memo: return retval equals to pthread_exit((void *)retval)
//Memo: automatically handlers are closed after exit
} // End of client therad
int main() // The primary thread of the server
{
int m = 0;
SOCKET s = socket( // Create socket
AF_INET, // Internet address family
SOCK_STREAM, // Connection-oriented (stream) socket type
// which uses TCP packets (reliable, duplex)
// Can also be: SOCK_DGRAM - uses UDP packets
// (see chapter 10)
0); // Protocol (0 - system picks approp. protocol
// Returns socket descriptor (s)
if(s == INVALID_SOCKET)
{
cout << "Server failed to create a socket. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
}
else
{
cout << "Server successfully created a socket. " << endl;
}
SOCKADDR_IN sa; // Server socket address structure
sa.sin_family = AF_INET; // TCP Protocol
sa.sin_port = htons(PORT); // Supply the port number
sa.sin_addr.s_addr = htonl(INADDR_ANY);
m = bind( // Associate the local address with the socket
s, // Socket descriptor (returned by socket())
(LPSOCKADDR)&sa, // Pointer to the socket address structure
sizeof(sa)); // Length of the address structure
if (m == SOCKET_ERROR) {
cout << "Server failed to bind. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
} else if (m == 0) {
cout << "Server successfully binded." << endl;
}
m = listen( // Allow socket to take connections
s, // Socket descriptor (returned by socket())
MAX_CONNECTION);// Maximal number of requests allowed
if (m == SOCKET_ERROR) {
cout << "Server failed to listen connection. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
} else if (m == 0) {
cout << "Server is listening connection." << endl;
}
SOCKET cs[MAX_CONNECTION];
pthread_t thread[MAX_CONNECTION];
for(int i = 0; i < MAX_CONNECTION; i++) // Connection request loop
{
int length = sizeof(sa);
cs[i] = accept( // Accept a connection from a client
s, // Socket descriptor (returned by socket())
// (s identifies the socket which listens
// and accepts connection requests)
(LPSOCKADDR)&sa,// Socket address structure received from
// connecting entity (client)
&length); // Length of sa
// Returns new socket descriptor (ns)
if(cs[i] == INVALID_SOCKET)
{
cout << "Server failed to accept connection. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
break;
}
else
{
cout << "Server successfully accepted connection. Client ID: " << cs[i] << endl;
}
// Create Thread
m = pthread_create(
&thread[i], // thread id will be stored
NULL, // Thread's attributes.
// If attr is NULL, the default attributes are used.
ClientThread, // Pointer to the application-defined
// function to be executed by the thread
&cs[i] // Pointer to a variable to be passed to the thread.
);
if(m == 0)
{
cout << "Server successfully created a thread. Thread ID: " << thread[i] << endl;
}
else
{
cout << "Server failed to create a thread. " << endl;
cout << "Error code: " << m << endl;
break;
}
}
m = closesocket(s); // Release the socket descriptor s
// and delete all underlying structures
// (address info, queue and queued requests
// if any.)
// Returns 0 or SOCKET_ERROR
if (m == SOCKET_ERROR) {
cout << "Server failed to close server socket. " << endl;
cout << "Error code: " << WSAGetLastError() << endl;
exit(1);
} else if (m == 0) {
cout << "Server successfully closed server socket. " << endl;
}
return 0;
}// End of server
compile
cl -o server server.cpp -link wsock32.lib CC -mt -o pserver posix_server.c -lpthread -lsocket -lxnet
MyLib
getopt
ltrim/rtrim
char *ltrim(char *str) {
char *start = str;
while ((*start == ' ') || (*start == '\n'))
start++;
memmove(str, start, strlen(start) + 1);
return str;
}
char *rtrim(char *str) {
char *end = str;
while (*end)
end++;
end--;
while ((end >= str) && ((*end == ' ') || (*end == '\n')))
end--;
end[1] = '\0';
return str;
}
String *ltrimString(String *str) {
int i = 0;
while ((i < str->length) && (str->string[i] == ' '))
i++;
if (i == 0) /* nothing to trim */
return str;
str->length -= i;
memmove(str->string, &str->string[i], str->length + 1);
/* str->string = realloc(str->string, str->length); */
return str;
}
String *rtrimString(String *str) {
int i = str->length - 1;
while ((i >= 0) && (str->string[i] == ' '))
i--;
if (i == str->length - 1) /* nothing to trim */
return str;
str->length = i + 1;
str->string[i + 1] = '\0';
/* str->string = realloc(str->string, i + 1); */
return str;
}
basename/dirname
basename, dirname exists on unix. avoid these name. we can use them as
#if defined(_WIN32) || defined(_WIN64)
// create by own
#else
return dirname(filename);
#end
maybe, win does not have similar funcs.
#include <string.h>
char* get_basename(char* filename)
{
char* basename;
#if defined(_WIN32) || defined(_WIN64)
basename = strrchr(filename, '\\');
#else
basename = strrchr(filename, '/');
#endif
if (basename) {
basename = basename + 1;
} else {
basename = filename;
}
return basename;
}
#Include <stdlib.h>
#include <string.h>
char* get_dirname(char *filename)
{
char *dirname = NULL;
char *pch;
int pos;
#if defined(_WIN32) || defined(_WIN64)
pch = strrchr(filename, '\\');
#else
pch = strrchr(filename, '/');
#endif
if (pch) {
pos = pch - filename;
dirname = (char*) malloc(sizeof(char) * (pos + 1));
strncpy(dirname, filename, pos);
dirname[pos] = '\0';
}
return dirname;
}
boost basename/dirname
namespace fs = boost::filesystem; fs::path filename( "<path>" );
basename
std::string basename = filename.leaf();
dirname
std::string dirname = filename.branch_path().native_file_string();
/ を \ として展開したかったりするので、native_file_string() が付くのはわかるが、branch_path っつーのはいったいどんなセンスだ？
extension
std::string extension = boost::filesystem::extension( filename );
basename without extension
std::string stem = boost::filesystem::basename( filename );
phpstring
template
template は すべて #include でなければならない。コンパイルしてリンクではだめ。
サンプル - RingBuffer
#ifndef RINGBUFFER_H_
#define RINGBUFFER_H_
#include "boost/scoped_array.hpp"
/**
* Ring Buffer Data Structure.
*/
template <class T>
class RingBuffer
{
public:
/**
* Default buffer length
*/
static const unsigned int DEFAULT_LENGTH = 256;
protected:
/**
* Smart pointer for Buffer
*/
boost::scoped_array<T> buffer_ptr;
/**
* Pointer to point the newest one's index
*/
unsigned int newest;
/**
* Buffer length
*/
const unsigned int LENGTH;
public:
/**
* Constructor.
*
* @param length Buffer length.
* @param defaultValue Default value of contents of the buffer.
* @return -
*/
RingBuffer(
unsigned long length = DEFAULT_LENGTH,
T defaultValue = 0)
:
LENGTH(length)
{
this->buffer_ptr.reset(new T[this->LENGTH]);
T *buffer = this->buffer_ptr.get();
for (unsigned int i = 0; i < this->LENGTH; i++) {
buffer[i] = defaultValue;
}
this->initializeNewest();
}
/**
* Destructor.
*
* @param -
* @return -
*/
~RingBuffer(void)
{
}
public:
/**
* Get a direct memory access for a buffered array
*
* @return pointer for an array
*/
inline T* getArray(void) const
{
return this->buffer_ptr.get();
}
protected:
/**
* Convert the ring buffer index to the physical memory index.
*
* @param i Ring buffer index (0 denotes the newest value)
* @return Physical memory index (index of buffer[] array)
*/
inline unsigned int getIndex(unsigned int i) const
{
return (i + this->newest) % this->LENGTH;
};
/**
* Initialize the newest pointer.
*
* @param -
* @return -
*/
inline void initializeNewest()
{
this->newest = 0;
}
/**
* Forward the newest pointer.
*
* @param -
* @return -
*/
inline void forwardNewest()
{
this->newest = (this->newest == 0 ? this->LENGTH - 1 : this->newest - 1);
}
public:
/**
* Get the length of the buffer
*
* @param -
* @return length
*/
inline unsigned int getLength() const
{
return this->LENGTH;
}
/**
* Get the value at index i
* where 0 denotes the newest one and
* obj->getLength()-1 denotes the oldest one.
*
* @param i index
* @return value
*/
inline T get(unsigned int i = 0) const
{
T* buffer = this->buffer_ptr.get();
return buffer[this->getIndex(i)];
}
/**
* Push the new value and remove the oldest value.
*
* @param newValue New value
* @return Removed oldest value
*/
T push(T newValue)
{
printf("hoge\n");
this->forwardNewest();
T *buffer = this->buffer_ptr.get();
T oldestValue = buffer[this->newest];
buffer[this->newest] = newValue;
return oldestValue;
}
};
#endif // RINGBUFFER_H_
#include <stdio.h>
#include "RingBuffer.hpp"
#include "boost/scoped_ptr.hpp"
// /usr/bin/g++ -I/usr/include/boost-1_33_1 TestRingBuffer.cpp
int main() {
int num = 3;
boost::scoped_ptr< RingBuffer<int> > buf_ptr(new RingBuffer<int>(num));
RingBuffer<int> *buffer = buf_ptr.get();
buffer->push(1);
buffer->push(2);
buffer->push(3);
for (int i = 0; i < num; i++) {
printf("%d\n", buffer->get(i));
// 3 2 1
}
buffer->push(4);
for (int i = 0; i < num; i++) {
printf("%d\n", buffer->get(i));
// 4 3 2
}
//delete buffer;
}
継承
virtual
継承すなわちvirtual ということはない。
ポリモーフィズム(dynamic binding)を使いたい場合は、親クラスのそのメソッドに virtual をつけておく。
static binding (ただの機能拡張)でよいのならば、別にいらない。
parent
C++ に parent ポインタはない（多重継承のため)
ただし、
MathRingBuffer(
unsigned long length = RingBuffer<T>::DEFAULT_LENGTH,
T defaultValue = 0)
:
RingBuffer<T>(length, defaultValue)
{
this->sum = defaultValue * length;
this->avg = defaultValue;
}
のように親のコンストラクタを呼ぶことはできる。＃コンストラクタ、デストラクタは何もしなくても親のものも呼ばれる(virtual であろうがなかろうが)。型が違う場合に意図的に呼ぶのに便利。
他にもセッターぐらいなら呼べるが getter は返り値があるのできびしい。
template の継承
#ifndef MATHRINGBUFFER_H_
#define MATHRINGBUFFER_H_
#include "boost/scoped_array.hpp"
#include "RingBuffer.hpp"
/**
* Ring Buffer Data Structure extending statistical functions
*/
template <class T>
class MathRingBuffer : public RingBuffer<T>
{
protected:
/**
* Sum of elements.
*/
double sum;
/**
* Average of elements.
*/
double avg;
/**
* Difference between the newest and the oldest element.
*/
double diff;
public:
/**
* Constructor.
*
* @param length Buffer length.
* @param defaultValue Default value of contents of the buffer.
* @return -
*/
MathRingBuffer(
unsigned long length = RingBuffer<T>::DEFAULT_LENGTH,
T defaultValue = 0)
:
RingBuffer<T>(length, defaultValue)
{
this->sum = defaultValue * length;
this->avg = defaultValue;
}
/**
* Destructor.
*
* @param -
* @return -
*/
~MathRingBuffer(void)
{
}
public:
/**
* Get the sum of elements.
*
* @return sum of elements
*/
inline double getSum(void)
{
return this->sum;
}
/**
* Get the average of elements.
*
* @return average of elements
*/
inline double getAvg(void)
{
return this->avg;
}
/**
* Get the difference between the newest and the oldest element.
*
* @return difference between the newest and the oldest
*/
inline double getDiff(void)
{
return this->diff;
}
public:
/**
* Push the new value and remove the oldest value.
*
* @param newValue New value
* @return Removed oldest value
*/
T push(T newValue)
{
this->forwardNewest();
T *buffer = this->buffer_ptr.get();
T oldestValue = buffer[this->newest];
buffer[this->newest] = newValue;
this->diff = newValue - oldestValue;
this->sum += diff;
this->avg += diff / (double)this->LENGTH;
return oldestValue;
}
};
#endif // MATHRINGBUFFER_H_