[CPP] Add std::getline(...) and cin>>std::string()

Author: scopeInfinity

src/usr/include/iostream.h

@@ -19,7 +19,10 @@ class istream {
 public:
     istream& operator>>(char &c);
     istream& operator>>(char *str);
-    istream& operator>>(int &num);
+    istream& operator>>(std::string &str);
+
+    istream& get(char &c);
+    istream& get_line(char *str, std::size_t n, char delim='\n');
 };
 
 extern ostream cout;

src/usr/include/string.h

@@ -47,6 +47,7 @@ class basic_string {
     const_iterator begin() const;
     const_iterator end() const;
 
+    void clear();
     void pop_back();
     CharT& back();
     CharT& front();
@@ -61,6 +62,8 @@ class basic_string {
 
 using string = basic_string<char>;
 
+std::istream& get_line(std::istream &i, std::string &str);
+
 }  // namespace std end
 
 #include <string.tcc>

src/usr/include/string.tcc

@@ -41,6 +41,12 @@ typename basic_string<CharT>::const_iterator basic_string<CharT>::begin() const
 template <typename CharT>
 typename basic_string<CharT>::const_iterator basic_string<CharT>::end() const { return this->_data.end() - 1; }
 
+template <typename CharT>
+void basic_string<CharT>::clear() {
+    this->_data.clear();
+    this->_data.push_back('\0');
+}
+
 template <typename CharT>
 void basic_string<CharT>::pop_back() {
     if(this->_data.size()>1) {
@@ -101,4 +107,14 @@ basic_string<CharT>& basic_string<CharT>::operator+=(const basic_string<CharT> &
     return *this;
 }
 
+std::istream& get_line(std::istream &i, std::string &str) {
+    char ch;
+    str.clear();
+    while (1) {
+        i.get(ch);
+        if (ch == '\n') break;
+        str += ch;
+    }
+}
+
 } // namespace std end

src/usr/include/vector.h

@@ -22,7 +22,7 @@ class vector {
     const_iterator begin() const;
     const_iterator end() const;
 
-    T *raw_data() const;
+    void clear();
     bool empty();
     std::size_t size();
     void push_back(const T &val);

src/usr/include/vector.tcc

@@ -56,6 +56,12 @@ void vector<T>::resize_capacity(std::size_t capacity) {
     this->_capacity = capacity;
 }
 
+template <typename T>
+void vector<T>::clear() {
+    // not reducing capacity for now
+    this->_size = 0;
+}
+
 template <typename T>
 bool vector<T>::empty() {
     return this->_size == 0;

src/usr/lib/iostream.cpp

@@ -3,17 +3,73 @@
 #include <conio.h>
 
 namespace std {
+#define __IS_WHITESPACE(ch) ((ch)==' ' || (ch)=='\n' || (ch)=='\t')
 
 const char endl = '\n';
 ostream cout;
 istream cin;
 
+
 ostream& ostream::operator<<(const char c) { putchar(c); return *this; }
 ostream& ostream::operator<<(const int num) { printf("%d", num); return *this; }
 ostream& ostream::operator<<(const char *str) { puts(str); return *this; }
 ostream& ostream::operator<<(const std::string &str) { puts(str.c_str()); return *this; }
 
-istream& istream::operator>>(char &c) { c = getch(); putchar(c); return *this; }
-istream& istream::operator>>(char *str) { gets(str); return *this; }
+istream& istream::operator>>(char &c) {
+    do {
+        this->get(c);
+    } while (__IS_WHITESPACE(c));
+    return *this;
+}
+
+istream& istream::operator>>(char *str) {
+    char c;
+    bool leading_whitespace = 1;
+    while(1) {
+        this->get(c);
+        if (leading_whitespace) {
+            if(__IS_WHITESPACE(c)) continue;
+            leading_whitespace = 0;
+        } else {
+            // from second non-whitespace character
+            if(__IS_WHITESPACE(c)) break;
+        }
+        *(str++) = c;
+    };
+    *(str++) = '\0';
+    return *this;
+}
+
+istream& istream::operator>>(std::string &str) {
+    str.clear();
+    char c;
+    bool leading_whitespace = 1;
+    while(1) {
+        this->get(c);
+        if (leading_whitespace) {
+            if(__IS_WHITESPACE(c)) continue;
+            leading_whitespace = 0;
+        } else {
+            // from second non-whitespace character
+            if(__IS_WHITESPACE(c)) break;
+        }
+        str += c;
+    };
+    return *this;
+}
+
+istream& istream::get(char &c) { c = getch(); putchar(c); return *this; }
+
+istream& istream::get_line(char *str, std::size_t n, char delim) {
+    char c;
+    while (n-- > 0) {
+        this->get(c);
+        if (c == delim) break;
+        *(str++) = c;
+    }
+    *(str) = '\0';
+    return *this;
+}
 
+#undef __IS_WHITESPACE
 }  // namespace std end