HttpLineReader: prevent memory overflow

Author: pschatzmann

src/AudioConfig.h

@@ -114,16 +114,9 @@
 #define PWM_FREQUENCY 60000
 #endif
 
-/**
- * ------------------------------------------------------------------------- 
- * @brief Activate decoders - only after installing them !
- */
-
-//#define USE_HELIX
-//#define USE_FDK
-//#define USE_LAME
-//#define USE_MAD
-
+#ifndef MAX_HTTP_HEADER_LINE_LENGTH
+#define MAX_HTTP_HEADER_LINE_LENGTH 240
+#endif
 
 /**
  * ------------------------------------------------------------------------- 

src/AudioHttp/HttpHeader.h

@@ -2,6 +2,7 @@
 
 #include "AudioBasic/Collections.h"
 #include "AudioBasic/StrExt.h"
+#include "AudioConfig.h"
 #include "AudioHttp/HttpLineReader.h" 
 #include "AudioHttp/Url.h"
 #include "AudioHttp/HttpTypes.h" 
@@ -10,7 +11,6 @@
 namespace audio_tools {
 
 // Class Configuration
-const int MaxHeaderLineLength = 240;
 
 // Define relevant header content
 const char* CONTENT_TYPE = "Content-Type";
@@ -225,18 +225,18 @@ class HttpHeader {
             // remove all existing value
             clear();
 
-            char line[MaxHeaderLineLength];   
+            char line[MAX_HTTP_HEADER_LINE_LENGTH];   
             if (in.connected()){
                 if (in.available()==0) {
                     LOGW("Waiting for data...");
                     while(in.available()==0){
                         delay(500);
                     }
                 }
-                readLine(in, line, MaxHeaderLineLength);
+                readLine(in, line, MAX_HTTP_HEADER_LINE_LENGTH);
                 parse1stLine(line);
                 while (in.available()){
-                    readLine(in, line, MaxHeaderLineLength);
+                    readLine(in, line, MAX_HTTP_HEADER_LINE_LENGTH);
                     if (isValidStatus() || isRedirectStatus()){
                         Str lineStr(line);
                         lineStr.ltrim();
@@ -421,11 +421,11 @@ class HttpReplyHeader : public HttpHeader  {
         // reads the final chunked reply headers 
         void readExt(Client &in) {
             LOGI("HttpReplyHeader::readExt");
-            char line[MaxHeaderLineLength];   
-            readLine(in, line, MaxHeaderLineLength);
+            char line[MAX_HTTP_HEADER_LINE_LENGTH];   
+            readLine(in, line, MAX_HTTP_HEADER_LINE_LENGTH);
             while(strlen(line)!=0){
                 put(line);                
-                readLine(in, line, MaxHeaderLineLength);
+                readLine(in, line, MAX_HTTP_HEADER_LINE_LENGTH);
             }
         }
 

src/AudioHttp/HttpLineReader.h

@@ -30,12 +30,19 @@ class HttpLineReader {
             }
 
             // process characters
+            bool is_buffer_owerflow = false;
             for (int j=0;j<len;j++){
                 int c = client.read();
                 if (c==-1){
                     break;
                 }
-                result++;
+
+                if (j<len){
+                    result++;
+                } else {
+                    is_buffer_owerflow = true;
+                }
+
                 if (c=='\n'){
                     if (incl_nl){
                         str[j]=c;
@@ -55,9 +62,15 @@ class HttpLineReader {
                         }
                     }
                 }
-                str[j] = c;
+                if (!is_buffer_owerflow){
+                    str[j] = c;
+                }
             }
             str[result]=0;
+            if (is_buffer_owerflow){
+                LOGE("Line cut off");
+            }
+
             return result;
         }
 };