base: Rewrite the CircleBuf to fix bugs and add serialization

The CircleBuf class has at least one bug causing it to overwrite the
wrong elements when wrapping. The current code has a lot of unused
functionality and duplicated code. This changeset replaces the old
implementation with a new version that supports serialization and
arbitrary types in the buffer (not just char).

src/dev/terminal.cc

@@ -205,8 +205,12 @@ Terminal::accept()
     write((const uint8_t *)stream.str().c_str(), stream.str().size());
 
     DPRINTFN("attach terminal %d\n", number);
-
-    txbuf.readall(data_fd);
+    char buf[1024];
+    for (size_t i = 0; i < txbuf.size(); i += sizeof(buf)) {
+        const size_t chunk_len(std::min(txbuf.size() - i, sizeof(buf)));
+        txbuf.peek(buf, chunk_len);
+        write((const uint8_t *)buf, chunk_len);
+    }
 }
 
 void
@@ -329,7 +333,7 @@ Terminal::out(char c)
                 DPRINTF(Terminal, "%s\n", buffer);
                 delete [] buffer;
             } else {
-                linebuf.write(c);
+                linebuf.write(&c, 1);
             }
         }
 
@@ -337,7 +341,7 @@ Terminal::out(char c)
     }
 #endif
 
-    txbuf.write(c);
+    txbuf.write(&c, 1);
 
     if (data_fd >= 0)
         write(c);

src/dev/terminal.hh

@@ -109,11 +109,11 @@ class Terminal : public SimObject
     void accept();
 
   protected:
-    CircleBuf txbuf;
-    CircleBuf rxbuf;
+    CircleBuf<char> txbuf;
+    CircleBuf<char> rxbuf;
     std::ostream *outfile;
 #if TRACING_ON == 1
-    CircleBuf linebuf;
+    CircleBuf<char> linebuf;
 #endif
 
   public: