[code] Python console that stores and displays commands that are

entered.

Change-Id: I0343c38b60f4bbea6dfab173e2b5f46f66b83251

apps/code/console_store.cpp

@@ -0,0 +1,101 @@
+#include "console_store.h"
+#include <assert.h>
+#include <string.h>
+
+namespace Code {
+
+ConsoleStore::ConsoleStore() :
+  m_history{0}
+{
+}
+
+ConsoleLine ConsoleStore::lineAtIndex(int i) const {
+  assert(i >= 0 && i < numberOfLines());
+  int currentLineIndex = 0;
+  for (int j=0; j<k_historySize; j++) {
+    if (m_history[j] == 0) {
+      currentLineIndex++;
+      j++;
+    }
+    if (currentLineIndex == i) {
+      return ConsoleLine(lineTypeForMarker(m_history[j]), m_history+j+1);
+    }
+  }
+  assert(false);
+  return ConsoleLine();
+}
+
+int ConsoleStore::numberOfLines() const {
+  if (m_history[0] == 0) {
+    return 0;
+  }
+  int result = 0;
+  for (int i=0; i<k_historySize; i++) {
+    if (m_history[i] == 0) {
+      result++;
+      if (m_history[i+1] == 0) {
+        return result;
+      }
+    }
+  }
+  assert(false);
+  return 0;
+}
+
+void ConsoleStore::pushCommand(const char * text, size_t length) {
+  push(CommandMarker, text, length);
+}
+
+void ConsoleStore::pushResult(const char * text, size_t length) {
+  push(ResultMarker, text, length);
+}
+
+void ConsoleStore::push(const char marker, const char * text, size_t length) {
+  // TODO: Verify that the text field does not accept texts that are bigger than
+  // k_historySize, or put an alert message if the command is too big.
+  assert(ConsoleLine::sizeOfConsoleLine(length) < k_historySize);
+
+  int i = indexOfNullMarker();
+  // If needed, make room for the text we want to push.
+  while (i + ConsoleLine::sizeOfConsoleLine(length) > k_historySize - 1) {
+    deleteFirstLine();
+    i = indexOfNullMarker();
+  }
+  m_history[i] = marker;
+  strlcpy(&m_history[i+1], text, length+1);
+  m_history[i+1+length+1] = 0;
+}
+
+ConsoleLine::Type ConsoleStore::lineTypeForMarker(char marker) const {
+  assert(marker == 0x01 || marker == 0x02);
+  return static_cast<ConsoleLine::Type>(marker-1);
+}
+
+int ConsoleStore::indexOfNullMarker() const {
+  if (m_history[0] == 0) {
+    return 0;
+  }
+  for (int i=0; i<k_historySize; i++) {
+    if (m_history[i] == 0 && m_history[i+1] == 0) {
+      return (i+1);
+    }
+  }
+  assert(false);
+  return 0;
+}
+
+void ConsoleStore::deleteFirstLine() {
+  if (m_history[0] == 0) {
+    return;
+  }
+  int indexOfSecondLineMarker = 1;
+  while (m_history[indexOfSecondLineMarker] != 0) {
+    indexOfSecondLineMarker++;
+  }
+  indexOfSecondLineMarker++;
+  for (int i=0; i<k_historySize - indexOfSecondLineMarker; i++) {
+    m_history[i] = m_history[indexOfSecondLineMarker+i];
+  }
+}
+
+}