From 596334598103f7cc2966ae869789f25daa1c5b16 Mon Sep 17 00:00:00 2001
From: Romain Goyet <romain.goyet@numworks.com>
Date: Tue, 20 Dec 2016 17:27:45 +0100
Subject: [PATCH] [poincare] NULL-termination and Integer parsing

Discard non-10 base handling for now

Change-Id: I487e85a169c7ae5780c83b0bcf3c40bd3daac0fe
---
 poincare/include/poincare/integer.h |  2 +-
 poincare/src/expression_parser.y    |  2 +-
 poincare/src/integer.cpp            | 49 +++++++++++------------------
 poincare/test/integer.cpp           |  4 +--
 4 files changed, 22 insertions(+), 35 deletions(-)

diff --git a/poincare/include/poincare/integer.h b/poincare/include/poincare/integer.h
index 6e4079afb..df8491fa9 100644
--- a/poincare/include/poincare/integer.h
+++ b/poincare/include/poincare/integer.h
@@ -12,7 +12,7 @@ class Integer : public LeafExpression {
   public:
     Integer(native_int_t i);
     Integer(Integer&& other); // C++11 move constructor
-    Integer(const char * string); // NULL-terminated
+    Integer(const char * digits, bool negative = false); // Digits are NOT NULL-terminated
     Type type() const override;
 
     ~Integer();
diff --git a/poincare/src/expression_parser.y b/poincare/src/expression_parser.y
index 12234ccb6..77cdc336b 100644
--- a/poincare/src/expression_parser.y
+++ b/poincare/src/expression_parser.y
@@ -101,7 +101,7 @@ mtxData:
   | mtxData LEFT_BRACKET lstData RIGHT_BRACKET  { $$ = $1; $$->pushListData($3); }
 
 exp:
-  INTEGER            { $$ = new Integer($1);     }
+  INTEGER            { $$ = new Integer($1, false);     }
   | SYMBOL           { $$ = new Symbol($1); }
   | exp PLUS exp     { Expression * terms[2] = {$1,$3}; $$ = new Addition(terms, 2, false); }
   | exp MINUS exp    { Expression * terms[2] = {$1,$3}; $$ = new Subtraction(terms, false); }
diff --git a/poincare/src/integer.cpp b/poincare/src/integer.cpp
index 948a879b4..6ec14c483 100644
--- a/poincare/src/integer.cpp
+++ b/poincare/src/integer.cpp
@@ -46,46 +46,33 @@ Integer::Integer(native_int_t i) {
   *m_digits = (native_uint_t)(i>0 ? i : -i);
 }
 
-Integer::Integer(const char * string) {
-  int stringLength = strlen(string);
+/* Caution: string is NOT guaranteed to be NULL-terminated! */
+Integer::Integer(const char * digits, bool negative) {
+  m_negative = negative;
 
-  Integer base = Integer(10);
-
-  m_negative = false;
-
-  if (stringLength > 1 && string[0] == '-') {
+  if (digits != nullptr && digits[0] == '-') {
     m_negative = true;
-    string += 1;
-    stringLength -= 1;
+    digits++;
   }
-  if (stringLength > 2 && string[0] == '0') {
-    switch (string[1]) {
-      case 'x':
-        base = Integer(16);
-        string += 2;
-        stringLength -= 2;
-        break;
-      case 'b':
-        base = Integer(2);
-        string += 2;
-        stringLength -= 2;
-        break;
+
+  Integer result = Integer(0);
+
+  if (digits != nullptr) {
+    Integer base = Integer(10);
+    while (*digits >= '0' && *digits <= '9') {
+      result = result.multiply_by(base);
+      result = result.add(Integer(*digits-'0'));
+      digits++;
     }
   }
 
-  Integer v = Integer(digit_from_char(string[0]));
-  for (int i=1; i<stringLength; i++) {
-    v = v.multiply_by(base);
-    v = v.add(Integer(digit_from_char(string[i]))); // ASCII encoding
-  }
-
   // Pilfer v's ivars
-  m_numberOfDigits = v.m_numberOfDigits;
-  m_digits = v.m_digits;
+  m_numberOfDigits = result.m_numberOfDigits;
+  m_digits = result.m_digits;
 
   // Zero-out v
-  v.m_numberOfDigits = 0;
-  v.m_digits = NULL;
+  result.m_numberOfDigits = 0;
+  result.m_digits = NULL;
 }
 
 Integer::~Integer() {
diff --git a/poincare/test/integer.cpp b/poincare/test/integer.cpp
index 78139f711..068a05f51 100644
--- a/poincare/test/integer.cpp
+++ b/poincare/test/integer.cpp
@@ -8,8 +8,8 @@ QUIZ_CASE(poincare_integer) {
   assert(!(Integer("-123") == Integer(123)));
   assert(Integer("-123") == Integer(-123));
   //assert(Integer("0123") == Integer(123));
-  assert(Integer("0x2BABE") == Integer(178878));
-  assert(Integer("0b1011") == Integer(11));
+  //FIXME: assert(Integer("0x2BABE") == Integer(178878));
+  //FIXME: assert(Integer("0b1011") == Integer(11));
 }
 
 QUIZ_CASE(poincare_integer_compare) {