Refactor duplicated code patterns in NetTool

NetTool/NetTool.vcxproj

@@ -149,6 +149,7 @@
   </ItemDefinitionGroup>
   <ItemGroup>
     <ClCompile Include="finger.cpp" />
+    <ClCompile Include="common_utils.cpp" />
     <ClCompile Include="IPArp.Cpp" />
     <ClCompile Include="IPConfig.cpp" />
     <ClCompile Include="IPRoute.Cpp" />
@@ -169,6 +170,7 @@
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="finger.h" />
+    <ClInclude Include="common_utils.h" />
     <ClInclude Include="IPArp.h" />
     <ClInclude Include="IPConfig.h" />
     <ClInclude Include="iphdr.h" />

NetTool/Ping.cpp

@@ -1,5 +1,6 @@
 #include "ping.h"
 #include "iphdr.h"
+#include "common_utils.h"
 
 
 int gAddressFamily = AF_UNSPEC,    // Address family to use
@@ -12,7 +13,7 @@ recvbuf[MAX_RECV_BUF_LEN];     // For received packets
 int recvbuflen = MAX_RECV_BUF_LEN; // Length of received packets.
 
 
-#pragma warning(disable : 28159) //����ʹ�á�GetTickCount64�������ǡ�GetTickCount��
+#pragma warning(disable : 28159) //����ʹ�á�GetTickCount64�������ǡ�GetTickCount��
 
 
 //////////////////////////////////////////////////////////////////////////////////////////////////
@@ -505,7 +506,6 @@ int ping(int argc, char ** argv)
 \Windows-classic-samples\Samples\Win7Samples\netds\winsock\ping\Ping.cpp
 */
 {
-    WSADATA wsd;
     WSAOVERLAPPED recvol;
     SOCKET s = INVALID_SOCKET;
     char * icmpbuf = NULL;
@@ -524,9 +524,10 @@ int ping(int argc, char ** argv)
         goto EXIT;
     }
 
-    // Load Winsock
-    if ((rc = WSAStartup(MAKEWORD(2, 2), &wsd)) != 0) {
-        printf("WSAStartup() failed: %d\n", rc);
+    // Load Winsock using RAII wrapper
+    WinsockInitializer winsock(MAKEWORD(2, 2));
+    if (!winsock.IsInitialized()) {
+        printf("WSAStartup() failed: %d\n", winsock.GetErrorCode());
         status = -1;
         goto EXIT;
     }
@@ -687,7 +688,7 @@ int ping(int argc, char ** argv)
     if (icmpbuf)
         HeapFree(GetProcessHeap(), 0, icmpbuf);
 
-    WSACleanup();
+    // Winsock cleanup is handled automatically by WinsockInitializer destructor
 
 EXIT:
     return status;

NetTool/common_utils.cpp

@@ -0,0 +1,118 @@
+#include "common_utils.h"
+#include <errno.h>
+
+// Global variables for getopt
+int opterr = 1;       // if error message should be printed
+int optind = 1;       // index into parent argv vector
+int optopt;           // character checked for validity
+const char* optarg;   // argument associated with option
+
+#pragma warning(disable : 28182)
+
+int getopt(int nargc, char* const* nargv, const char* ostr)
+{
+    static const char* place = EMSG; // option letter processing
+    register char* oli;              // option letter list index
+    char* p;
+
+    if (!*place) { // update scanning pointer
+        if (optind >= nargc || *(place = nargv[optind]) != '-') {
+            place = EMSG;
+            return (EOF);
+        }
+        if (place[1] && *++place == '-') { // found "--"
+            ++optind;
+            place = EMSG;
+            return (EOF);
+        }
+    } // option letter okay?
+    if ((optopt = (int)*place++) == (int)':' || !(oli = (char*)strchr(ostr, optopt))) {
+        /*
+         * if the user didn't specify '-' as an option, assume it means EOF.
+         */
+        if (optopt == (int)'-')
+            return (EOF);
+        if (!*place)
+            ++optind;
+        if (opterr) {
+            if (!(p = strrchr(*nargv, '/')))
+                p = *nargv;
+            else
+                ++p;
+            (void)fprintf(stderr, "%s: illegal option -- %c\n", p, optopt);
+        }
+        return (BADCH);
+    }
+    if (*++oli != ':') { // don't need argument
+        optarg = NULL;
+        if (!*place)
+            ++optind;
+    }
+    else {        // need an argument
+        if (*place) // no white space
+            optarg = place;
+        else if (nargc <= ++optind) { // no arg
+            place = EMSG;
+            if (!(p = strrchr(*nargv, '/')))
+                p = *nargv;
+            else
+                ++p;
+            if (opterr)
+                (void)fprintf(stderr, "%s: option requires an argument -- %c\n", p, optopt);
+            return (BADCH);
+        }
+        else // white space
+            optarg = nargv[optind];
+
+        place = EMSG;
+        ++optind;
+    }
+
+    return (optopt); // dump back option letter
+}
+
+void verr(int eval, const char* fmt, va_list ap)
+{
+    int sverrno;
+    extern char* __progname;
+
+    sverrno = errno;
+    (void)fprintf(stderr, "%s: ", __progname);
+    if (fmt != NULL) {
+        (void)vfprintf(stderr, fmt, ap);
+        (void)fprintf(stderr, ": ");
+    }
+
+#pragma warning(push)
+#pragma warning(disable : 4996)
+    (void)fprintf(stderr, "%s\n", strerror(sverrno));
+#pragma warning(pop)
+
+    exit(eval);
+}
+
+void err(int eval, const char* fmt, ...)
+{
+    va_list ap;
+    va_start(ap, fmt);
+    verr(eval, fmt, ap);
+    va_end(ap);
+}
+
+void verrx(int eval, const char* fmt, va_list ap)
+{
+    extern char* __progname;
+    (void)fprintf(stderr, "%s: ", __progname);
+    if (fmt != NULL)
+        (void)vfprintf(stderr, fmt, ap);
+    (void)fprintf(stderr, "\n");
+    exit(eval);
+}
+
+void errx(int eval, const char* fmt, ...)
+{
+    va_list ap;
+    va_start(ap, fmt);
+    verrx(eval, fmt, ap);
+    va_end(ap);
+}

NetTool/common_utils.h

@@ -0,0 +1,52 @@
+#pragma once
+
+#include "pch.h"
+
+// RAII wrapper for Winsock initialization
+class WinsockInitializer {
+private:
+    BOOL initialized;
+    int errorCode;
+
+public:
+    WinsockInitializer(WORD versionRequested = MAKEWORD(2, 2)) : initialized(FALSE), errorCode(0) {
+        WSADATA wsaData;
+        errorCode = WSAStartup(versionRequested, &wsaData);
+        initialized = (errorCode == 0);
+    }
+
+    ~WinsockInitializer() {
+        if (initialized) {
+            WSACleanup();
+        }
+    }
+
+    BOOL IsInitialized() const {
+        return initialized;
+    }
+
+    int GetErrorCode() const {
+        return errorCode;
+    }
+
+    // Delete copy constructor and assignment operator
+    WinsockInitializer(const WinsockInitializer&) = delete;
+    WinsockInitializer& operator=(const WinsockInitializer&) = delete;
+};
+
+// Common getopt implementation (from BSD)
+// Global variables for getopt
+extern int opterr, optind, optopt;
+extern const char* optarg;
+
+#define BADCH   (int)'?'
+#define EMSG    ""
+
+// getopt function declaration
+int getopt(int nargc, char* const* nargv, const char* ostr);
+
+// Error handling functions (from BSD)
+void verr(int eval, const char* fmt, va_list ap);
+void err(int eval, const char* fmt, ...);
+void verrx(int eval, const char* fmt, va_list ap);
+void errx(int eval, const char* fmt, ...);