Optimize string generation function

Author: yuzegao

src/Handler.cpp

@@ -660,22 +660,7 @@ bool Handler::preHandleRequest(Request* req, const String& key)
 
             // Debug log: cursor received from client
             char cursorBuf[64];
-            int cursorLen = 0;
-            if (cursor == 0) {
-                cursorBuf[cursorLen++] = '0';
-            } else {
-                char temp[64];
-                int tempLen = 0;
-                __uint128_t c = cursor;
-                while (c > 0) {
-                    temp[tempLen++] = '0' + (c % 10);
-                    c /= 10;
-                }
-                for (int i = tempLen - 1; i >= 0; i--) {
-                    cursorBuf[cursorLen++] = temp[i];
-                }
-            }
-            cursorBuf[cursorLen] = '\0';
+            Util::uint128ToString(cursor, cursorBuf);
 
             int groupIdx = (unsigned long)(cursor & Const::ServGroupMask);
             auto g = sp->getGroup(groupIdx);
@@ -701,22 +686,7 @@ bool Handler::preHandleRequest(Request* req, const String& key)
 
                     // Debug log: cursor to be sent to backend server
                     char actualCursorBuf[64];
-                    int actualLen = 0;
-                    if (actualCursor == 0) {
-                        actualCursorBuf[actualLen++] = '0';
-                    } else {
-                        char temp[64];
-                        int tempLen = 0;
-                        __uint128_t c = actualCursor;
-                        while (c > 0) {
-                            temp[tempLen++] = '0' + (c % 10);
-                            c /= 10;
-                        }
-                        for (int i = tempLen - 1; i >= 0; i--) {
-                            actualCursorBuf[actualLen++] = temp[i];
-                        }
-                    }
-                    actualCursorBuf[actualLen] = '\0';
+                    Util::uint128ToString(actualCursor, actualCursorBuf);
 
                     logDebug("h %d SCAN cursor from client: %s, group: %d, cursor to server: %s",
                             id(), cursorBuf, groupIdx, actualCursorBuf);
@@ -901,23 +871,7 @@ void Handler::handleResponse(ConnectConnection* s, Request* req, Response* res)
                 if ((p = strchr(p, '*')) != nullptr) {
                     // Convert 128-bit integer to string
                     char buf[64];  // 128-bit needs at most 39 decimal digits
-                    int n = 0;
-                    if (cursor == 0) {
-                        buf[n++] = '0';
-                    } else {
-                        char temp[64];
-                        int tempLen = 0;
-                        __uint128_t c = cursor;
-                        while (c > 0) {
-                            temp[tempLen++] = '0' + (c % 10);
-                            c /= 10;
-                        }
-                        // Reverse digits (extracted from low to high)
-                        for (int i = tempLen - 1; i >= 0; i--) {
-                            buf[n++] = temp[i];
-                        }
-                    }
-                    buf[n] = '\0';
+                    int n = Util::uint128ToString(cursor, buf);
 
                     // Debug log: cursor to be sent to client
                     logDebug("h %d SCAN cursor from server: %s, group: %d, cursor to client: %s",

src/Request.cpp

@@ -249,23 +249,7 @@ void Request::setSentinelSlaves(const String& master)
 void Request::adjustScanCursor(__uint128_t cursor)
 {
     char buf[64];  // 128-bit integer needs at most 39 decimal digits
-    int n = 0;
-    if (cursor == 0) {
-        buf[n++] = '0';
-    } else {
-        char temp[64];
-        int tempLen = 0;
-        __uint128_t c = cursor;
-        while (c > 0) {
-            temp[tempLen++] = '0' + (c % 10);
-            c /= 10;
-        }
-        // Reverse digits (extracted from low to high)
-        for (int i = tempLen - 1; i >= 0; i--) {
-            buf[n++] = temp[i];
-        }
-    }
-    buf[n] = '\0';
+    int n = Util::uint128ToString(cursor, buf);
     if (mHead.empty()) {
         SegmentStr<64> str(mReq);
         const char* p = strchr(str.data(), '$');

src/Util.h

@@ -81,6 +81,31 @@ namespace Util
     {
         return duration_cast<microseconds>(steady_clock::now().time_since_epoch()).count();
     }
+    
+    // Convert 128-bit unsigned integer to string
+    // Returns the length of the converted string (excluding null terminator)
+    // The buffer must be at least 40 bytes (39 digits + null terminator for max __uint128_t value)
+    inline int uint128ToString(__uint128_t value, char* buf)
+    {
+        int n = 0;
+        if (value == 0) {
+            buf[n++] = '0';
+        } else {
+            char temp[64];
+            int tempLen = 0;
+            __uint128_t v = value;
+            while (v > 0) {
+                temp[tempLen++] = '0' + (v % 10);
+                v /= 10;
+            }
+            // Reverse digits (extracted from low to high)
+            for (int i = tempLen - 1; i >= 0; i--) {
+                buf[n++] = temp[i];
+            }
+        }
+        buf[n] = '\0';
+        return n;
+    }
 };
 
 #endif