Upgraded TempBuffer logic to use .get() to return pointer

Next up: update Network.cpp to use client.available() and reduce fixed memory usage.

src/HAP.cpp

@@ -164,15 +164,14 @@ void HAPClient::processRequest(){
     return;
   }
  
-  TempBuffer <uint8_t> tempBuffer(messageSize+1);      // leave room for null character added below
+  TempBuffer <uint8_t> httpBuf(messageSize+1);      // leave room for null character added below
-  uint8_t *httpBuf=tempBuffer.buf;
   
   if(cPair){                           // expecting encrypted message
     LOG2("<<<< #### ");
     LOG2(client.remoteIP());
     LOG2(" #### <<<<\n");
 
-    nBytes=receiveEncrypted(httpBuf,messageSize);   // decrypt and return number of bytes read      
+    nBytes=receiveEncrypted(httpBuf.get(),messageSize);   // decrypt and return number of bytes read      
         
     if(!nBytes){                           // decryption failed (error message already printed in function)
       badRequestError();              
@@ -184,7 +183,7 @@ void HAPClient::processRequest(){
     LOG2(client.remoteIP());
     LOG2(" <<<<<<<<<\n");
     
-    nBytes=client.read(httpBuf,messageSize);   // read expected number of bytes
+    nBytes=client.read(httpBuf.get(),messageSize);   // read expected number of bytes
 
     if(nBytes!=messageSize || client.available()!=0){
       badRequestError();
@@ -194,12 +193,12 @@ void HAPClient::processRequest(){
                
   } // encrypted/plaintext
       
-  httpBuf[nBytes]='\0';         // add null character to enable string functions
+  httpBuf.get()[nBytes]='\0';   // add null character to enable string functions
       
-  char *body=(char *)httpBuf;   // char pointer to start of HTTP Body
+  char *body=(char *)httpBuf.get();   // char pointer to start of HTTP Body
-  char *p;                      // char pointer used for searches
+  char *p;                            // char pointer used for searches
      
-  if(!(p=strstr((char *)httpBuf,"\r\n\r\n"))){
+  if(!(p=strstr((char *)httpBuf.get(),"\r\n\r\n"))){
     badRequestError();
     LOG0("\n*** ERROR:  Malformed HTTP request (can't find blank line indicating end of BODY)\n\n");
     return;      
@@ -875,7 +874,7 @@ int HAPClient::getAccessoriesURL(){
 
   int nBytes = homeSpan.sprintfAttributes(NULL);        // get size of HAP attributes JSON
   TempBuffer <char> jBuf(nBytes+1);
-  homeSpan.sprintfAttributes(jBuf.buf);                  // create JSON database (will need to re-cast to uint8_t* below)
+  homeSpan.sprintfAttributes(jBuf.get());                  // create JSON database (will need to re-cast to uint8_t* below)
 
   int nChars=snprintf(NULL,0,"HTTP/1.1 200 OK\r\nContent-Type: application/hap+json\r\nContent-Length: %d\r\n\r\n",nBytes);      // create '200 OK' Body with Content Length = size of JSON Buf
   char body[nChars+1];
@@ -885,10 +884,10 @@ int HAPClient::getAccessoriesURL(){
   LOG2(client.remoteIP());
   LOG2(" >>>>>>>>>>\n");
   LOG2(body);
-  LOG2(jBuf.buf);
+  LOG2(jBuf.get());
   LOG2("\n");
   
-  sendEncrypted(body,(uint8_t *)jBuf.buf,nBytes);
+  sendEncrypted(body,(uint8_t *)jBuf.get(),nBytes);
          
   return(1);
   
@@ -1507,10 +1506,10 @@ void HAPClient::sendEncrypted(char *body, uint8_t *dataBuf, int dataLen){
 
   TempBuffer <uint8_t> tBuf(totalBytes);
   
-  tBuf.buf[count]=bodyLen%256;         // store number of bytes in first frame that encrypts the Body (AAD bytes)
+  tBuf.get()[count]=bodyLen%256;         // store number of bytes in first frame that encrypts the Body (AAD bytes)
-  tBuf.buf[count+1]=bodyLen/256;
+  tBuf.get()[count+1]=bodyLen/256;
   
-  crypto_aead_chacha20poly1305_ietf_encrypt(tBuf.buf+count+2,&nBytes,(uint8_t *)body,bodyLen,tBuf.buf+count,2,NULL,a2cNonce.get(),a2cKey);   // encrypt the Body with authentication tag appended
+  crypto_aead_chacha20poly1305_ietf_encrypt(tBuf.get()+count+2,&nBytes,(uint8_t *)body,bodyLen,tBuf.get()+count,2,NULL,a2cNonce.get(),a2cKey);   // encrypt the Body with authentication tag appended
 
   a2cNonce.inc();                 // increment nonce
   
@@ -1523,17 +1522,17 @@ void HAPClient::sendEncrypted(char *body, uint8_t *dataBuf, int dataLen){
     if(n>FRAME_SIZE)           // maximum number of bytes to encrypt=FRAME_SIZE
       n=FRAME_SIZE;                                     
     
-    tBuf.buf[count]=n%256;    // store number of bytes that encrypts this frame (AAD bytes)
+    tBuf.get()[count]=n%256;    // store number of bytes that encrypts this frame (AAD bytes)
-    tBuf.buf[count+1]=n/256;
+    tBuf.get()[count+1]=n/256;
 
-    crypto_aead_chacha20poly1305_ietf_encrypt(tBuf.buf+count+2,&nBytes,dataBuf+i,n,tBuf.buf+count,2,NULL,a2cNonce.get(),a2cKey);   // encrypt the next portion of dataBuf with authentication tag appended
+    crypto_aead_chacha20poly1305_ietf_encrypt(tBuf.get()+count+2,&nBytes,dataBuf+i,n,tBuf.get()+count,2,NULL,a2cNonce.get(),a2cKey);   // encrypt the next portion of dataBuf with authentication tag appended
 
     a2cNonce.inc();            // increment nonce
 
     count+=2+n+16;             // increment count by 2-byte AAD record + length of JSON + 16-byte authentication tag
   }
  
-  client.write(tBuf.buf,count);   // transmit all encrypted frames to Client
+  client.write(tBuf.get(),count);   // transmit all encrypted frames to Client
 
   LOG2("-------- SENT ENCRYPTED! --------\n");
       

src/HAP.h

@@ -134,7 +134,7 @@ struct HAPClient {
   static void hexPrintRow(uint8_t *buf, int n, int minLogLevel=0);        // prints 'n' bytes of *buf as HEX, all on one row, subject to specified minimum log level
   static void charPrintRow(uint8_t *buf, int n, int minLogLevel=0);       // prints 'n' bytes of *buf as CHAR, all on one row, subject to specified minimum log level
   
-  static Controller *findController(uint8_t *id);                                      // returns pointer to controller with mathching ID (or NULL if no match)
+  static Controller *findController(uint8_t *id);                                      // returns pointer to controller with matching ID (or NULL if no match)
   static Controller *getFreeController();                                              // return pointer to next free controller slot (or NULL if no free slots)
   static Controller *addController(uint8_t *id, uint8_t *ltpk, boolean admin);         // stores data for new Controller with specified data.  Returns pointer to Controller slot on success, else NULL
   static int nAdminControllers();                                                      // returns number of admin Controllers stored

src/HomeSpan.cpp

@@ -599,10 +599,10 @@ void Span::processSerialCommand(const char *c){
     case 'd': {      
       
       TempBuffer <char> qBuf(sprintfAttributes(NULL)+1);
-      sprintfAttributes(qBuf.buf);  
+      sprintfAttributes(qBuf.get());  
 
       LOG0("\n*** Attributes Database: size=%d  configuration=%d ***\n\n",qBuf.len()-1,hapConfig.configNumber);
-      prettyPrint(qBuf.buf);
+      prettyPrint(qBuf.get());
       LOG0("\n*** End Database ***\n\n");
     }
     break;
@@ -1009,12 +1009,12 @@ void Span::processSerialCommand(const char *c){
       LOG0("\n*** Pairing Data used for Cloning another Device\n\n");
       size_t olen;
       TempBuffer<char> tBuf(256);
-      mbedtls_base64_encode((uint8_t *)tBuf.buf,256,&olen,(uint8_t *)&HAPClient::accessory,sizeof(struct Accessory));
+      mbedtls_base64_encode((uint8_t *)tBuf.get(),256,&olen,(uint8_t *)&HAPClient::accessory,sizeof(struct Accessory));
-      LOG0("Accessory data:  %s\n",tBuf.buf);
+      LOG0("Accessory data:  %s\n",tBuf.get());
       for(int i=0;i<HAPClient::MAX_CONTROLLERS;i++){
         if(HAPClient::controllers[i].allocated){
-          mbedtls_base64_encode((uint8_t *)tBuf.buf,256,&olen,(uint8_t *)(HAPClient::controllers+i),sizeof(struct Controller));
+          mbedtls_base64_encode((uint8_t *)tBuf.get(),256,&olen,(uint8_t *)(HAPClient::controllers+i),sizeof(struct Controller));
-          LOG0("Controller data: %s\n",tBuf.buf);
+          LOG0("Controller data: %s\n",tBuf.get());
         }
       }
       LOG0("\n*** End Pairing Data\n\n");
@@ -1027,14 +1027,14 @@ void Span::processSerialCommand(const char *c){
       TempBuffer<char> tBuf(200);
       size_t olen;
 
-      tBuf.buf[0]='\0';
+      tBuf.get()[0]='\0';
       LOG0(">>> Accessory data:  ");
-      readSerial(tBuf.buf,199);
+      readSerial(tBuf.get(),199);
-      if(strlen(tBuf.buf)==0){
+      if(strlen(tBuf.get())==0){
         LOG0("(cancelled)\n\n");
         return;
       }
-      mbedtls_base64_decode((uint8_t *)&HAPClient::accessory,sizeof(struct Accessory),&olen,(uint8_t *)tBuf.buf,strlen(tBuf.buf));
+      mbedtls_base64_decode((uint8_t *)&HAPClient::accessory,sizeof(struct Accessory),&olen,(uint8_t *)tBuf.get(),strlen(tBuf.get()));
       if(olen!=sizeof(struct Accessory)){
         LOG0("\n*** Error in size of Accessory data - cloning cancelled.  Restarting...\n\n");
         reboot();
@@ -1044,15 +1044,15 @@ void Span::processSerialCommand(const char *c){
       }
       
       for(int i=0;i<HAPClient::MAX_CONTROLLERS;i++){
-        tBuf.buf[0]='\0';
+        tBuf.get()[0]='\0';
         LOG0(">>> Controller data: ");
-        readSerial(tBuf.buf,199);
+        readSerial(tBuf.get(),199);
-        if(strlen(tBuf.buf)==0){
+        if(strlen(tBuf.get())==0){
           LOG0("(done)\n");
           while(i<HAPClient::MAX_CONTROLLERS)              // clear data from remaining controller slots
             HAPClient::controllers[i++].allocated=false;
         } else {
-          mbedtls_base64_decode((uint8_t *)(HAPClient::controllers+i),sizeof(struct Controller),&olen,(uint8_t *)tBuf.buf,strlen(tBuf.buf));
+          mbedtls_base64_decode((uint8_t *)(HAPClient::controllers+i),sizeof(struct Controller),&olen,(uint8_t *)tBuf.get(),strlen(tBuf.get()));
           if(olen!=sizeof(struct Controller)){
             LOG0("\n*** Error in size of Controller data - cloning cancelled.  Restarting...\n\n");
             reboot();
@@ -1577,8 +1577,8 @@ boolean Span::updateDatabase(boolean updateMDNS){
 
   uint8_t tHash[48];
   TempBuffer <char> tBuf(sprintfAttributes(NULL,GET_META|GET_PERMS|GET_TYPE|GET_DESC)+1);
-  sprintfAttributes(tBuf.buf,GET_META|GET_PERMS|GET_TYPE|GET_DESC);  
+  sprintfAttributes(tBuf.get(),GET_META|GET_PERMS|GET_TYPE|GET_DESC);  
-  mbedtls_sha512_ret((uint8_t *)tBuf.buf,tBuf.len(),tHash,1);     // create SHA-384 hash of JSON (can be any hash - just looking for a unique key)
+  mbedtls_sha512_ret((uint8_t *)tBuf.get(),tBuf.len(),tHash,1);     // create SHA-384 hash of JSON (can be any hash - just looking for a unique key)
 
   boolean changed=false;
 

src/HomeSpan.h

@@ -712,8 +712,8 @@ class SpanCharacteristic{
     size_t olen;
     mbedtls_base64_encode(NULL,0,&olen,data,len);                    // get length of string buffer needed (mbedtls includes the trailing null in this size)
     TempBuffer<char> tBuf(olen);                                     // create temporary string buffer, with room for trailing null
-    mbedtls_base64_encode((uint8_t*)tBuf.buf,olen,&olen,data,len );  // encode data into string buf
+    mbedtls_base64_encode((uint8_t*)tBuf.get(),olen,&olen,data,len );  // encode data into string buf
-    setString(tBuf.buf);                                             // call setString to continue processing as if characteristic was a string
+    setString(tBuf.get());                                             // call setString to continue processing as if characteristic was a string
   }  
 
   template <typename T> void setVal(T val, boolean notify=true){

src/Network.cpp

@@ -117,8 +117,8 @@ void Network::apConfigure(){
   WiFiServer apServer(80);
   client=0;
   
-  TempBuffer <uint8_t> tempBuffer(MAX_HTTP+1);
+  TempBuffer <uint8_t> httpBuf(MAX_HTTP+1);
-  uint8_t *httpBuf=tempBuffer.buf;
+//  uint8_t *httpBuf=tempBuffer.buf;
   
   const byte DNS_PORT = 53;
   DNSServer dnsServer;
@@ -179,7 +179,7 @@ void Network::apConfigure(){
       LOG2(client.remoteIP());
       LOG2(" <<<<<<<<<\n");
     
-      int nBytes=client.read(httpBuf,MAX_HTTP+1);       // read all available bytes up to maximum allowed+1
+      int nBytes=client.read(httpBuf.get(),MAX_HTTP+1);       // read all available bytes up to maximum allowed+1
        
       if(nBytes>MAX_HTTP){                              // exceeded maximum number of bytes allowed
         badRequestError();
@@ -187,11 +187,11 @@ void Network::apConfigure(){
         continue;
       }
 
-      httpBuf[nBytes]='\0';                             // add null character to enable string functions    
+      httpBuf.get()[nBytes]='\0';                             // add null character to enable string functions    
-      char *body=(char *)httpBuf;                       // char pointer to start of HTTP Body
+      char *body=(char *)httpBuf.get();                       // char pointer to start of HTTP Body
       char *p;                                          // char pointer used for searches
       
-      if(!(p=strstr((char *)httpBuf,"\r\n\r\n"))){
+      if(!(p=strstr((char *)httpBuf.get(),"\r\n\r\n"))){
         badRequestError();
         LOG0("\n*** ERROR:  Malformed HTTP request (can't find blank line indicating end of BODY)\n\n");
         continue;      

src/Utils.h

@@ -42,10 +42,15 @@ String mask(char *c, int n);          // simply utility that creates a String fr
 // going out of scope
 
 template <class bufType>
-struct TempBuffer {
+class TempBuffer {
+
+  private:
+  
   bufType *buf;
   int nBytes;
 
+  public:
+  
   TempBuffer(size_t len){
     nBytes=len*sizeof(bufType);
     buf=(bufType *)malloc(nBytes);
@@ -65,6 +70,10 @@ struct TempBuffer {
     return(nBytes);
   }
 
+  bufType *get(){
+    return(buf);
+  }
+  
 };
 
 ////////////////////////////////