commit ceb7cae5806c7f63ca458115a470fe81d08d38ff
Author: Simon Kirby <sim@netnation.com>
Date:   Sat Mar 17 00:55:15 2012 -0700

    Implement cli tab completion.

diff --git a/baseflight/src/cli.c b/baseflight/src/cli.c
index 06bbed0..cf6e4f6 100644
--- a/baseflight/src/cli.c
+++ b/baseflight/src/cli.c
@@ -30,8 +30,6 @@ const cliCmd cmdTable[] = {
 static void cliPrompt(void)
 {
     uartPrint("\r\n# ");
-    memset(cliBuffer, 0, sizeof(cliBuffer));
-    bufferIndex = 0;
 }
 
 static int cliCompare(const void *a, const void *b)
@@ -42,7 +40,7 @@ static int cliCompare(const void *a, const void *b)
 
 static void cliExit(char *cmdline)
 {
-    uartPrint("Leaving CLI mode...\r\n");
+    uartPrint("\r\nLeaving CLI mode...\r\n");
     memset(cliBuffer, 0, sizeof(cliBuffer));
     bufferIndex = 0;
     cliMode = 0;
@@ -72,6 +70,7 @@ static void cliRMode(char *cmdline)
         featureSet(FEATURE_PPM);
     }
     
+    cliExit(cmdline);
     writeParams();
     systemReset(false);
 }
@@ -83,20 +82,56 @@ static void cliVersion(char *cmdline)
 
 void cliProcess(void)
 {
+    if (!cliMode) {
+        cliMode = 1;
+        uartPrint("\r\nEntering CLI Mode, type 'exit' to return\r\n");
+        cliPrompt();
+    }
     while (uartAvailable()) {
         uint8_t c = uartRead();
 
-    	cliBuffer[bufferIndex++] = c;
-        if (bufferIndex == sizeof(cliBuffer)) {
-            bufferIndex--;
-            c = '\n';
-        }
-
-    	if (bufferIndex && (c == '\n' || c == '\r')) {
+        if (c == '\t' || c == '?') {
+            const cliCmd *cmd, *pstart = NULL, *pend = NULL;
+            int i = bufferIndex;
+            for (cmd = cmdTable;cmd < cmdTable + CMD_COUNT;cmd++) {
+                if (bufferIndex && (strncasecmp(cliBuffer, cmd->name, bufferIndex) != 0))
+                    continue;
+                if (!pstart)
+                    pstart = cmd;
+                pend = cmd;
+            }
+            if (pstart) {    /* Buffer matches one or more commands */
+                for (;;bufferIndex++) {
+                    if (pstart->name[bufferIndex] != pend->name[bufferIndex])
+                        break;
+                    if (!pstart->name[bufferIndex]) {
+                        /* Unambiguous -- append a space */
+                        cliBuffer[bufferIndex++] = ' ';
+                        break;
+                    }
+                    cliBuffer[bufferIndex] = pstart->name[bufferIndex];
+                }
+            }
+            if (!bufferIndex || pstart != pend) {
+                /* Print list of ambiguous matches */
+                uartPrint("\r\033[K");
+                for (cmd = pstart;cmd <= pend;cmd++) {
+                    uartPrint(cmd->name);
+                    uartWrite('\t');
+                }
+                cliPrompt();
+                i = 0;    /* Redraw prompt */
+            }
+            for (;i < bufferIndex;i++)
+                uartWrite(cliBuffer[i]);
+        } else if (!bufferIndex && c == 4) {
+            cliExit(cliBuffer);
+            return;
+        } else if (bufferIndex && (c == '\n' || c == '\r')) {
             // enter pressed
             cliCmd *cmd = NULL;
             cliCmd target;
-    		uartPrint("\r\n");
+            uartPrint("\r\n");
             cliBuffer[bufferIndex] = 0; // null terminate
             
             target.name = cliBuffer;
@@ -108,25 +143,23 @@ void cliProcess(void)
             else
                 uartPrint("ERR: Unknown command, try 'HELP'");
 
-            // 'exit' will reset this flag, so we don't need to print prompt again
-            if (cliMode)
-    	        cliPrompt();
+            memset(cliBuffer, 0, sizeof(cliBuffer));
+            bufferIndex = 0;
 
-        } else if (c == 127) {
+            // 'exit' will reset this flag, so we don't need to print prompt again
+            if (!cliMode)
+                return;
+            cliPrompt();
+        } else if (c == 8 || c == 127) {
             // backspace
-            if (bufferIndex > 1) {
-        		cliBuffer[bufferIndex - 2] = 0;
-        		uartPrint("\r# ");
-        		uartPrint(cliBuffer);
-        		uartWrite(' ');
-        		uartPrint("\r# ");
-        		uartPrint(cliBuffer);
-        		bufferIndex -= 2;
+            if (bufferIndex) {
+                cliBuffer[--bufferIndex] = 0;
+                uartPrint("\010 \010");
             }
-        } else if (c < 32 || c > 126) {
-            // non-printable ascii
-            bufferIndex--;
-        } else {
+        } else if (bufferIndex < sizeof(cliBuffer) && c >= 32 && c <= 126) {
+            if (!bufferIndex && c == 32)
+                continue;
+            cliBuffer[bufferIndex++] = c;
             uartWrite(c);
         }
     }
diff --git a/baseflight/src/serial.c b/baseflight/src/serial.c
index 088f42b..fb540f8 100755
--- a/baseflight/src/serial.c
+++ b/baseflight/src/serial.c
@@ -33,8 +33,7 @@ void serialCom(void)
     if (uartAvailable()) {
         switch (uartRead()) {
         case '#':
-            uartPrint("\r\nEntering CLI Mode, type 'exit' to return\r\n");
-            cliMode = 1;
+            cliProcess();
             break;
 
 #ifdef BTSERIAL