WIP: Simplify the library

cpp-terminal/terminal.h

@@ -19,8 +19,29 @@
 #include <string>
 #include <vector>
 #include <thread>
-#define CTRL_KEY(k) (char)(((unsigned char)(k) & 0x1f))
-#define ALT_KEY(k) (char)(((unsigned char)(k) + 0x80))
+#define CTRL_KEY(k) (char)((unsigned char)(k) & 0x1f)
+#define ALT_KEY(k) (char)((unsigned char)(k) + 0x80)
+
+#define cursor_off "\x1b[?25l"
+#define cursor_on "\x1b[?25h"
+// If an attempt is made to move the cursor out of the window, the result is
+// undefined.
+#define move_cursor(row,col) "\x1b[" + std::to_string(row) + ";" + std::to_string(col) + "H"
+// If an attempt is made to move the cursor to the right of the right margin,
+// the cursor stops at the right margin.
+#define move_cursor_right(col) "\x1b[" + std::to_string(col) + "C"
+// If an attempt is made to move the cursor below the bottom margin, the cursor
+// stops at the bottom margin.
+#define move_cursor_down(row) "\x1b[" + std::to_string(row) + "B"
+#define cursor_position_report "\x1b[6n"
+#define erase_to_eol "\x1b[K"
+#define color(value) std::string("\033[") + std::to_string((int)value) + "m"
+#define restore_screen_code "\033[?1049l"
+#define save_screen_code "\033[?1049h"
+#define restore_cursor_pos "\033" "8"
+#define save_cursor_pos "\033" "7"
+#define ansi_esc '\x1b'
+#define ansi_carriagereturn '\x0d'
 
 namespace Term {
 
@@ -83,53 +104,6 @@ enum class bgB {
     gray = 107
 };
 
-template <typename T>
-std::string color(T const value)
-{
-    return "\033[" + std::to_string(static_cast<int>(value)) + "m";
-}
-
-inline std::string cursor_off()
-{
-    return "\x1b[?25l";
-}
-
-inline std::string cursor_on()
-{
-    return "\x1b[?25h";
-}
-
-// If an attempt is made to move the cursor out of the window, the result is
-// undefined.
-inline std::string move_cursor(size_t row, size_t col)
-{
-    return "\x1b[" + std::to_string(row) + ";" + std::to_string(col) + "H";
-}
-
-// If an attempt is made to move the cursor to the right of the right margin,
-// the cursor stops at the right margin.
-inline std::string move_cursor_right(int col)
-{
-    return "\x1b[" + std::to_string(col) + "C";
-}
-
-// If an attempt is made to move the cursor below the bottom margin, the cursor
-// stops at the bottom margin.
-inline std::string move_cursor_down(int row)
-{
-    return "\x1b[" + std::to_string(row) + "B";
-}
-
-inline std::string cursor_position_report()
-{
-    return "\x1b[6n";
-}
-
-inline std::string erase_to_eol()
-{
-    return "\x1b[K";
-}
-
 enum Key {
     BACKSPACE = 1000,
     ENTER,
@@ -179,22 +153,19 @@ class Terminal: public BaseTerminal {
     void restore_screen()
     {
         if (restore_screen_) {
-            write("\033[?1049l"); // restore screen
-            write("\033" "8");    // restore current cursor position
+            std::cout << restore_screen_code
+                      << restore_cursor_pos
+                      << std::flush;
             restore_screen_ = false;
         }
     }
 
     void save_screen()
     {
         restore_screen_ = true;
-        write("\033" "7");    // save current cursor position
-        write("\033[?1049h"); // save screen
-    }
-
-    static inline void write(const std::string& s)
-    {
-        std::cout << s << std::flush;
+        std::cout << save_cursor_pos
+                  << save_screen_code
+                  << std::flush;
     }
 
     // Waits for a key press, translates escape codes
@@ -217,7 +188,7 @@ class Terminal: public BaseTerminal {
         if (!read_raw(&c))
             return 0;
 
-        if (c == '\x1b') {
+        if (c == ansi_esc) {
             char seq[4];
 
             if (!read_raw(&seq[0]))
@@ -227,7 +198,7 @@ class Terminal: public BaseTerminal {
                     // gnome-term, Windows Console
                     return ALT_KEY(seq[0]);
                 }
-                if (seq[0] == '\x0d') {
+                if (seq[0] == ansi_carriagereturn) {
                     // gnome-term
                     return Key::ALT_ENTER;
                 }
@@ -384,61 +355,34 @@ class Terminal: public BaseTerminal {
     void get_cursor_position(int& rows, int& cols) const
     {
         char buf[32];
-        unsigned int i = 0;
-        write(cursor_position_report());
-        while (i < sizeof(buf) - 1) {
-            while (!read_raw(&buf[i])) {
-            };
+        std::cout << cursor_position_report
+                  << std::endl;
+        for (unsigned int i = 0; i < sizeof(buf) -1; i++) {
+            while (!read_raw(&buf[i]));
             if (buf[i] == 'R')
+            {
+                if (i < 5)
+                    throw std::runtime_error("get_cursor_position(): too short response");
+                else
+                    buf[i] = '\0';
                 break;
-            i++;
-        }
-        buf[i] = '\0';
-        if (i < 5) {
-            throw std::runtime_error("get_cursor_position(): too short response");
+            }
         }
         // Find the result in the response, drop the rest:
-        i = 0;
-        while (i < sizeof(buf) - 1 - 5) {
+        for (unsigned int i = 0; i < sizeof(buf) - 6; i++) {
             if (buf[i] == '\x1b' && buf[i+1] == '[') {
-                if (convert_string_to_int(&buf[i+2], "%d;%d", &rows, &cols) == 2) {
-                    return;
-                } else {
+                if (convert_string_to_int(&buf[i+2], "%d;%d", &rows, &cols) != 2) {
                     throw std::runtime_error("get_cursor_position(): result could not be parsed");
                 }
+                return;
             }
-            if (buf[i] == '\0') break;
-            i++;
+            if (buf[i] == '\0') 
+                break;
         }
         throw std::runtime_error("get_cursor_position(): result not found in the response");
     }
-
-    // This function takes about 23ms, so it should only be used as a fallback
-    void get_term_size_slow(int& rows, int& cols) const
-    {
-        struct CursorOff {
-            const Terminal& term;
-            explicit CursorOff(const Terminal& term)
-                : term{ term }
-            {
-                Term::Terminal::write(cursor_off());
-            }
-            ~CursorOff()
-            {
-                Term::Terminal::write(cursor_on());
-            }
-        };
-        CursorOff cursor_off(*this);
-        int old_row, old_col;
-        get_cursor_position(old_row, old_col);
-        write(move_cursor_right(999) + move_cursor_down(999));
-        get_cursor_position(rows, cols);
-        write(move_cursor(old_row, old_col));
-    }
 };
 
-
-
 /*----------------------------------------------------------------------------*/
 
 #define	UTF8_ACCEPT	0
@@ -512,7 +456,7 @@ inline std::u32string utf8_to_utf32(const std::string &s)
         if (state == UTF8_ACCEPT) {
             r.push_back(codepoint);
         }
-        if (state == UTF8_REJECT) {
+        else if (state == UTF8_REJECT) {
             throw std::runtime_error("Invalid byte in UTF8 encoded string");
         }
     }
@@ -678,7 +622,7 @@ class Window
 
     std::string render() {
         std::string out;
-        out.append(cursor_off());
+        out.append(cursor_off);
         fg current_fg = fg::reset;
         bg current_bg = bg::reset;
         style current_style = style::reset;
@@ -718,7 +662,7 @@ class Window
         if (current_fg != fg::reset) out.append(color(fg::reset));
         if (current_bg != bg::reset) out.append(color(bg::reset));
         if (current_style != style::reset) out.append(color(style::reset));
-        out.append(cursor_on());
+        out.append(cursor_on);
         return out;
     }
 };
@@ -736,15 +680,15 @@ struct Model
 inline std::string render(const Model &m, int prompt_row, int term_cols)
 {
     std::string out;
-    out = cursor_off();
+    out = cursor_off;
     out += move_cursor(prompt_row, 1) + m.prompt_string + m.input;
     size_t last_col = m.prompt_string.size() + m.input.size();
     for (size_t i=0; i < term_cols-last_col; i++) {
         out.append(" ");
     }
     out.append(move_cursor(prompt_row+m.cursor_row-1,
         m.prompt_string.size() + m.cursor_col));
-    out.append(cursor_on());
+    out.append(cursor_on);
     return out;
 }
 

cpp-terminal/terminal_base.h

@@ -41,6 +41,28 @@
 #    include <cerrno>
 #endif
 
+// Returns true if the standard input is attached to a terminal
+#ifdef _WIN32
+        #define is_stdin_a_tty _isatty(_fileno(stdin))
+#else
+        #define is_stdin_a_tty isatty(STDIN_FILENO)
+#endif
+// Returns true if the standard output is attached to a terminal
+#ifdef _WIN32
+        #define is_stdout_a_tty _isatty(_fileno(stdout)
+#else
+        #define is_stdout_a_tty isatty(STDOUT_FILENO)
+#endif
+
+// coverts a string into an integer
+#ifdef _WIN32
+        // windows provides it's own alternative to sscanf()
+        #define convert_string_to_int(string, format, rows, cols) sscanf_s(string, format, rows, cols)
+#else
+        // TODO move to a better way
+        #define convert_string_to_int(string, format, rows, cols) sscanf(string, format, rows, cols)
+#endif
+
 namespace Term {
 
 /* Note: the code that uses Terminal must be inside try/catch block, otherwise
@@ -108,6 +130,7 @@ class BaseTerminal {
                 throw std::runtime_error("SetConsoleMode() failed");
             }
         }
+    }
 #else
     explicit BaseTerminal(bool enable_keyboard=false, bool disable_ctrl_c=true)
         : keyboard_enabled{enable_keyboard}
@@ -232,42 +255,10 @@ class BaseTerminal {
             rows = ws.ws_row;
             return true;
         }
-#endif
-    }
-
-    // Returns true if the standard input is attached to a terminal
-    static bool is_stdin_a_tty()
-    {
-#ifdef _WIN32
-        return _isatty(_fileno(stdin));
-#else
-        return isatty(STDIN_FILENO);
-#endif
-    }
-
-    // Returns true if the standard output is attached to a terminal
-    static bool is_stdout_a_tty()
-    {
-#ifdef _WIN32
-        return _isatty(_fileno(stdout));
-#else
-        return isatty(STDOUT_FILENO);
-#endif
-    }
-
-    // coverts a string into an integer
-    static int convert_string_to_int(const char *string, const char *format, int* rows, int* cols)
-    {
-#ifdef _WIN32
-        // windows provides it's own alternative to sscanf()
-        return sscanf_s(string, format, rows, cols);
-#else
-        // TODO move to a better way
-        return sscanf(string, format, rows, cols);
 #endif
     }
 };
-
 } // namespace Term
 
-#endif // TERMINAL_BASE_H
+#endif 
+// TERMINAL_BASE_H

examples/colors.cpp

@@ -1,23 +1,21 @@
 #include <cpp-terminal/terminal.h>
 
 using Term::Terminal;
-using Term::color;
 using Term::fg;
 using Term::bg;
 using Term::style;
 
 int main() {
     try {
-        Terminal term;
-        if (Term::Terminal::is_stdout_a_tty()) {
+        if (is_stdout_a_tty) {
             std::cout << "Standard output is attached to a terminal."
-                << std::endl;
+                      << std::endl;
         } else {
             std::cout << "Standard output is not attached to a terminal."
                 << std::endl;
         }
         std::string text = "Some text with "
-            + color(fg::red) + color(bg::green) + "red on green"
+            + color(fg::red) + color(bg::green) + std::string("red on green")
             + color(bg::reset) + color(fg::reset) + " and some "
             + color(style::bold) + "bold text" + color(style::reset) + ".\n";
         text += "Unicode works too: originally written by Ondřej Čertík.";