ANSI code parsing is only half functional

.vscode/settings.json

@@ -1,5 +1,6 @@
 {
     "files.associations": {
-        "types.h": "c"
+        "types.h": "c",
+        "vga_text_mode.h": "c"
     }
 }

include/printf.h

@@ -0,0 +1,117 @@
+///////////////////////////////////////////////////////////////////////////////
+// \author (c) Marco Paland (info@paland.com)
+//             2014-2019, PALANDesign Hannover, Germany
+//
+// \license The MIT License (MIT)
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+// \brief Tiny printf, sprintf and snprintf implementation, optimized for speed on
+//        embedded systems with a very limited resources.
+//        Use this instead of bloated standard/newlib printf.
+//        These routines are thread safe and reentrant.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#ifndef _PRINTF_H_
+#define _PRINTF_H_
+
+#include <stdarg.h>
+#include <stddef.h>
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/**
+ * Output a character to a custom device like UART, used by the printf() function
+ * This function is declared here only. You have to write your custom implementation somewhere
+ * \param character Character to output
+ */
+void _putchar(char character);
+
+
+/**
+ * Tiny printf implementation
+ * You have to implement _putchar if you use printf()
+ * To avoid conflicts with the regular printf() API it is overridden by macro defines
+ * and internal underscore-appended functions like printf_() are used
+ * \param format A string that specifies the format of the output
+ * \return The number of characters that are written into the array, not counting the terminating null character
+ */
+#define printf printf_
+int printf_(const char* format, ...);
+
+
+/**
+ * Tiny sprintf implementation
+ * Due to security reasons (buffer overflow) YOU SHOULD CONSIDER USING (V)SNPRINTF INSTEAD!
+ * \param buffer A pointer to the buffer where to store the formatted string. MUST be big enough to store the output!
+ * \param format A string that specifies the format of the output
+ * \return The number of characters that are WRITTEN into the buffer, not counting the terminating null character
+ */
+#define sprintf sprintf_
+int sprintf_(char* buffer, const char* format, ...);
+
+
+/**
+ * Tiny snprintf/vsnprintf implementation
+ * \param buffer A pointer to the buffer where to store the formatted string
+ * \param count The maximum number of characters to store in the buffer, including a terminating null character
+ * \param format A string that specifies the format of the output
+ * \param va A value identifying a variable arguments list
+ * \return The number of characters that COULD have been written into the buffer, not counting the terminating
+ *         null character. A value equal or larger than count indicates truncation. Only when the returned value
+ *         is non-negative and less than count, the string has been completely written.
+ */
+#define snprintf  snprintf_
+#define vsnprintf vsnprintf_
+int  snprintf_(char* buffer, size_t count, const char* format, ...);
+int vsnprintf_(char* buffer, size_t count, const char* format, va_list va);
+
+
+/**
+ * Tiny vprintf implementation
+ * \param format A string that specifies the format of the output
+ * \param va A value identifying a variable arguments list
+ * \return The number of characters that are WRITTEN into the buffer, not counting the terminating null character
+ */
+#define vprintf vprintf_
+int vprintf_(const char* format, va_list va);
+
+
+/**
+ * printf with output function
+ * You may use this as dynamic alternative to printf() with its fixed _putchar() output
+ * \param out An output function which takes one character and an argument pointer
+ * \param arg An argument pointer for user data passed to output function
+ * \param format A string that specifies the format of the output
+ * \return The number of characters that are sent to the output function, not counting the terminating null character
+ */
+int fctprintf(void (*out)(char character, void* arg), void* arg, const char* format, ...);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+
+#endif  // _PRINTF_H_

include/shade/platform/drivers/vga_text_mode.h

@@ -3,6 +3,8 @@
 #define REG_SCREEN_CTRL 0x3d4
 #define REG_SCREEN_DATA 0x3d5
 
+#include <stdbool.h>
+
 enum {
     PRINT_COLOR_BLACK = 0,
 	PRINT_COLOR_BLUE = 1,
@@ -22,6 +24,11 @@ enum {
 	PRINT_COLOR_WHITE = 15,
 };
 
+typedef struct ansi_code_struct {
+    int flag;
+    int color;
+} ansi_color_code_t;
+
 const static int NUM_COLS = 80;
 const static int NUM_ROWS = 25;
 
@@ -30,15 +37,32 @@ struct Char {
     char color;
 };
 
+static bool is_parsing_ansi_string = false;
+static bool ansi_string_found_bracket = false;
+
+static bool ansi_string_found_semi = false;
+static bool ansi_string_found_m = false;
+
+static bool ansi_string_found_number = false;
+
+static int _flag = 0;
+static int _color = 0;
+
+static int working_num = 0;
+
 void clear_row(int row);
 void clear_all();
 
 void print_newline();
 void print_char(char character);
+void _print_char(char character);
 void print_set_color(char foreground, char background);
 void print_str(char* str);
 
 void set_cursor_pos(int col, int row);
 
 void kernel_msg_ok(char* msg);
+
+void handle_ansi_code(ansi_color_code_t code);
+
 #endif

include/shade/util.h

@@ -1,6 +1,9 @@
 #ifndef UTIL_H
 #define UTIL_H
 
+#define IS_DIGIT(x) (x == '0' || x == '1' || x == '2' || x == '3' || x == '4' || x == '5' || x == '6' || x == '7' || x == '8' || x == '9')
+#define IS_HEX(x) (IS_DIGIT(x) || x == 'a' || x == 'b' || x == 'c' || x == 'd' || x == 'e' || x == 'f')
+
 void memcpy(char *source, char *dest, int nbytes);
 void memset(char *dest, char val, int len);
 

src/kernel/kernel.c

@@ -1,31 +1,22 @@
 #include <shade/platform/ports.h>
-#include <shade/print.h>
+#include <shade/platform/drivers/vga_text_mode.h>
 #include <shade/platform/interrupts/idt.h>
 #include <shade/platform/interrupts/pic.h>
+#include <printf.h>
 
 void kernel_welcome() {
-    print_str("Welcome to ");
+    printf("Welcome to ");
     print_set_color(PRINT_COLOR_CYAN, PRINT_COLOR_BLACK);
-    print_str("Shade");
+    printf("Shade");
 	print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
-    print_str("!\n");
+    printf("!\nshadeOS kernel version ");
-	
-	print_str("shadeOS kernel version ");
-	
 	print_set_color(PRINT_COLOR_YELLOW, PRINT_COLOR_BLACK);
-	print_str("0.2.2");
+	printf("0.2.2\n");
-	
 	print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
-	print_newline();
+	printf("Running on ");
-	
-	print_str("Running on ");
-	
 	print_set_color(PRINT_COLOR_YELLOW, PRINT_COLOR_BLACK);
-	print_str("shade-development");
+	printf("shade-development\n");
-
     print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
-	
-	print_newline();
 }
 
 // kMain
@@ -41,14 +32,16 @@ void kmain() {
     kernel_msg_ok("Initialized display successfully\n");
     kernel_welcome();
 
-    print_str("Copyright (c) e3team 2022. All rights reserved.\n");
+    printf("Copyright (c) e3team 2022. All rights reserved.\n");
-    print_str("This program is provided \"as-is\" and no express or implied warranty is provided.\n");
+    printf("This program is provided \"as-is\" and no express or implied warranty is provided.\n");
-    print_str("The full license can be found at /sys/LICENCE on this system or ./LICENCE in the source tree.\n");
+    printf("The full license can be found at /sys/LICENCE on this system or ./LICENCE in the source tree.\n");
 
     pic_remap(0x20, 0x28);
     idt_assemble();
-    kernel_msg_ok("Enabled interrupts");
+    kernel_msg_ok("Enabled interrupts\n");
     __asm__ __volatile__("int $2");
 
+    printf("ANSI code test: double \x1b[3;31m \x1b[31m \x1b[12m \x1b[0m\n");
+
     for (;;) {}
 }

src/kernel/platform/drivers/vga_text_mode.c

@@ -0,0 +1,328 @@
+#include <shade/platform/drivers/vga_text_mode.h>
+#include <shade/platform/ports.h>
+#include <strings.h>
+
+int row = 0;
+int col = 0;
+char color = PRINT_COLOR_WHITE | PRINT_COLOR_BLACK << 4;
+
+void clear_row(int row) {
+    struct Char* buffer = (struct Char*) 0xb8000;
+
+    struct Char empty = (struct Char) {
+        character: ' ',
+        color: color,
+    };
+
+    for (int x = 0; x < NUM_COLS; x++) {
+        buffer[x + NUM_COLS * row] = empty;
+    }
+    set_cursor_pos(col, row);
+}
+
+void clear_all() {
+    for (int i = 0; i < NUM_ROWS; i++) {
+        clear_row(i);
+    }
+    set_cursor_pos(col, row);
+}
+
+void print_newline() {
+    struct Char* buffer = (struct Char*) 0xb8000;
+
+    col = 0;
+
+    if (row < NUM_ROWS - 1) {
+        row++;
+        return;
+    }
+
+    for (int row = 1; row < NUM_ROWS; row++) {
+        for (int col = 0; col < NUM_COLS; col++) {
+            struct Char character = buffer[col + NUM_COLS * row];
+            buffer[col + NUM_COLS * (row - 1)] = character;
+        }
+    }
+
+    clear_row(NUM_COLS - 1);
+    set_cursor_pos(col, row);
+}
+
+bool is_hexchar(char character) {
+    switch (character) {
+        case '0':
+        case '1':
+        case '2':
+        case '3':
+        case '4':
+        case '5':
+        case '6':
+        case '7':
+        case '8':
+        case '9':
+        case 'a':
+        case 'b':
+        case 'c':
+        case 'd':
+        case 'e':
+        case 'f':
+            return true;
+            break;
+        default:
+            return false;
+            break;
+    }
+}
+
+bool is_digit(char ch) {
+  return (ch >= '0') && (ch <= '9');
+}
+
+unsigned int _atoi(const char** str) {
+  unsigned int i = 0U;
+  while (is_digit(**str)) {
+    i = i * 10U + (unsigned int)(*((*str)++) - '0');
+  }
+  return i;
+}
+
+
+
+void print_char(char character) {
+    // ANSI parsing
+    // 1. is the current char \x1b?
+    if (character == '\x1b') {
+        // are we already printing an ansi string?
+        if (is_parsing_ansi_string) {
+            // string is invalid now
+            is_parsing_ansi_string = false;
+            return;
+        } else {
+            // no! set flag and continue
+            is_parsing_ansi_string = true;
+            return;
+        }
+    }
+
+    // 2. are we working on an ansi string right now?
+    if (is_parsing_ansi_string) {
+        if (!ansi_string_found_bracket && character != '[') {
+            // string is invalid, stop
+            is_parsing_ansi_string = false;
+            ansi_string_found_bracket = false;
+            working_num = 0;
+            ansi_string_found_m = false;
+            ansi_string_found_semi = false;
+            ansi_string_found_number = false;
+            _flag = 0;
+            _color = 0;
+            _print_char(character);
+            return;
+        } else {
+            // found bracket
+            ansi_string_found_bracket = true;
+            return;
+        }
+        if (ansi_string_found_bracket && !(ansi_string_found_semi || ansi_string_found_m)) {
+            // looking for flag OR color, idk yet
+            if (ansi_string_found_number) {
+                if (character == 'm') {
+                    if (ansi_string_found_m) {
+                        // invalid
+                        is_parsing_ansi_string = false;
+                        ansi_string_found_bracket = false;
+                        working_num = 0;
+                        ansi_string_found_m = false;
+                        ansi_string_found_semi = false;
+                        ansi_string_found_number = false;
+                        _flag = 0;
+                        _color = 0;
+                        _print_char(character);
+                        return;
+                    }
+                    ansi_string_found_m = true;
+                    // string is done
+                    _color = working_num;
+                    ansi_color_code_t code;
+                    code.flag = _flag;
+                    code.color = color;
+                    handle_ansi_code(code);
+                    is_parsing_ansi_string = false;
+                    ansi_string_found_bracket = false;
+                    working_num = 0;
+                    ansi_string_found_m = false;
+                    ansi_string_found_semi = false;
+                    ansi_string_found_number = false;
+                    _flag = 0;
+                    _color = 0;
+                    return;
+                } else if (character == ';') {
+                    if (ansi_string_found_semi) {
+                        // invalid
+                        is_parsing_ansi_string = false;
+                        ansi_string_found_bracket = false;
+                        working_num = 0;
+                        ansi_string_found_m = false;
+                        ansi_string_found_semi = false;
+                        ansi_string_found_number = false;
+                        _flag = 0;
+                        _color = 0;
+                        _print_char(character);
+                        return;
+                    }
+                    _flag = working_num;
+                    working_num = 0;
+                    ansi_string_found_number = false;
+                    ansi_string_found_semi = true;
+                    return;
+                }
+            }
+            if (!is_digit(character)) {
+                // not a digit, print out and discard existing string
+                is_parsing_ansi_string = false;
+                ansi_string_found_bracket = false;
+                working_num = 0;
+                ansi_string_found_m = false;
+                ansi_string_found_semi = false;
+                ansi_string_found_number = false;
+                _print_char(character);
+                return;
+            } else {
+                // is digit, add to working
+                working_num *= 10;
+                working_num += _atoi(character);
+                ansi_string_found_number = true;
+            }
+        }
+        if (ansi_string_found_bracket && ansi_string_found_semi && !ansi_string_found_m) {
+            if (ansi_string_found_number) {
+                if (character == 'm') {
+                    if (ansi_string_found_m) {
+                        // invalid
+                        is_parsing_ansi_string = false;
+                        ansi_string_found_bracket = false;
+                        working_num = 0;
+                        ansi_string_found_m = false;
+                        ansi_string_found_semi = false;
+                        ansi_string_found_number = false;
+                        _flag = 0;
+                        _color = 0;
+                        _print_char(character);
+                        return;
+                    }
+                    ansi_string_found_m = true;
+                    // string is done
+                    _color = working_num;
+                    ansi_color_code_t code;
+                    code.flag = _flag;
+                    code.color = _color;
+                    handle_ansi_code(code);
+                    is_parsing_ansi_string = false;
+                    ansi_string_found_bracket = false;
+                    working_num = 0;
+                    ansi_string_found_m = false;
+                    ansi_string_found_semi = false;
+                    ansi_string_found_number = false;
+                    _flag = 0;
+                    _color = 0;
+                    return;
+                }
+                if (!_is_digit(character)) {
+                    // not a digit, print out and discard existing string
+                    is_parsing_ansi_string = false;
+                    ansi_string_found_bracket = false;
+                    working_num = 0;
+                    ansi_string_found_m = false;
+                    ansi_string_found_semi = false;
+                    ansi_string_found_number = false;
+                    _flag = 0;
+                    _color = 0;
+                    _print_char(character);
+                    return;
+                } else {
+                    // is digit, add to working
+                    working_num *= 10;
+                    working_num += _atoi(character);
+                    ansi_string_found_number = true;
+                }
+            }
+        }
+    }
+
+    _print_char(character);
+    return;
+}
+
+void _print_char(char character) {
+    struct Char* buffer = (struct Char*) 0xb8000;
+
+    if (character == '\n') {
+        print_newline();
+        return;
+    }
+
+    if (col > NUM_COLS) {
+        print_newline();
+    }
+
+    struct Char cr = (struct Char) {
+        character: character,
+        color: color,
+    };
+    buffer[col + NUM_COLS * row] = cr;
+
+    col++;
+    set_cursor_pos(col, row);
+}
+
+void print_str(char* str) {
+    for (int i = 0; 1; i++) {
+        char character = (char) str[i];
+
+        if (character == '\0') {
+            return;
+        }
+
+        print_char(character);
+    }
+}
+
+void print_set_color(char foreground, char background) {
+    color = foreground + (background << 4);
+}
+
+void set_cursor_pos(int col, int row) {
+   int offset = col + NUM_COLS * row;
+   outb(REG_SCREEN_CTRL, 14);
+   outb(REG_SCREEN_DATA, (unsigned char)(offset >> 8));
+   outb(REG_SCREEN_CTRL, 15);
+   outb(REG_SCREEN_DATA, (unsigned char)(offset & 0xff)); 
+}
+
+void kernel_msg_ok(char* msg) {
+	char ok_p1[] = "[ ";
+	char ok_p2[] = "OK ";
+	char ok_p3[] = "] ";
+	
+	print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
+	print_str(ok_p1);
+	
+	print_set_color(PRINT_COLOR_GREEN, PRINT_COLOR_BLACK);
+	print_str(ok_p2);
+	
+	print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
+	print_str(ok_p3);
+	print_str(msg);
+}
+
+
+void handle_ansi_code(ansi_color_code_t code) {
+    char s[50];
+    itoa(code.flag, s);
+    print_str("ansi code: [");
+    print_str(s);
+    print_str(";");
+    itoa(code.color, s);
+    print_str(s);
+    print_str("m found\n");
+}

src/kernel/platform/interrupts/isr.c

@@ -1,21 +1,11 @@
-#include <shade/print.h>
+#include <printf.h>
 #include <shade/platform/interrupts/isr.h>
 
 void exception_handler(isr_xframe_t frame) {
-    char s[256];
+    printf(" %i: cpu: check_exception 0x%x err_code => %i\n", err_count, frame.base_frame.vector, frame.base_frame.error_code);
-    itoa(err_count, s);
-    print_str(" ");
-    print_str(s);
-    print_str(": cpu: check_exception ");
-    itoa(frame.base_frame.vector, s);
-    print_str(s);
-    print_str(" err_code => ");
-    itoa(frame.base_frame.error_code, s);
-    print_str(s);
-    print_str("\n");
     err_count++;
     if (err_count > ERR_MAX) {
-        print_str("cpu: ierr hit err_max, halt");
+        printf("cpu: ierr hit err_max, halt\n");
         __asm__ __volatile__("cli; hlt");
     }
 }

src/kernel/print.c

@@ -1,110 +0,0 @@
-#include <shade/print.h>
-#include <shade/platform/ports.h>
-
-int row = 0;
-int col = 0;
-char color = PRINT_COLOR_WHITE | PRINT_COLOR_BLACK << 4;
-
-void clear_row(int row) {
-    struct Char* buffer = (struct Char*) 0xb8000;
-
-    struct Char empty = (struct Char) {
-        character: ' ',
-        color: color,
-    };
-
-    for (int x = 0; x < NUM_COLS; x++) {
-        buffer[x + NUM_COLS * row] = empty;
-    }
-    set_cursor_pos(col, row);
-}
-
-void clear_all() {
-    for (int i = 0; i < NUM_ROWS; i++) {
-        clear_row(i);
-    }
-    set_cursor_pos(col, row);
-}
-
-void print_newline() {
-    struct Char* buffer = (struct Char*) 0xb8000;
-
-    col = 0;
-
-    if (row < NUM_ROWS - 1) {
-        row++;
-        return;
-    }
-
-    for (int row = 1; row < NUM_ROWS; row++) {
-        for (int col = 0; col < NUM_COLS; col++) {
-            struct Char character = buffer[col + NUM_COLS * row];
-            buffer[col + NUM_COLS * (row - 1)] = character;
-        }
-    }
-
-    clear_row(NUM_COLS - 1);
-    set_cursor_pos(col, row);
-}
-
-void print_char(char character) {
-    struct Char* buffer = (struct Char*) 0xb8000;
-
-    if (character == '\n') {
-        print_newline();
-        return;
-    }
-
-    if (col > NUM_COLS) {
-        print_newline();
-    }
-
-    struct Char cr = (struct Char) {
-        character: character,
-        color: color,
-    };
-    buffer[col + NUM_COLS * row] = cr;
-
-    col++;
-    set_cursor_pos(col, row);
-}
-
-void print_str(char* str) {
-    for (int i = 0; 1; i++) {
-        char character = (char) str[i];
-
-        if (character == '\0') {
-            return;
-        }
-
-        print_char(character);
-    }
-}
-
-void print_set_color(char foreground, char background) {
-    color = foreground + (background << 4);
-}
-
-void set_cursor_pos(int col, int row) {
-   int offset = col + NUM_COLS * row;
-   outb(REG_SCREEN_CTRL, 14);
-   outb(REG_SCREEN_DATA, (unsigned char)(offset >> 8));
-   outb(REG_SCREEN_CTRL, 15);
-   outb(REG_SCREEN_DATA, (unsigned char)(offset & 0xff)); 
-}
-
-void kernel_msg_ok(char* msg) {
-	char ok_p1[] = "[ ";
-	char ok_p2[] = "OK ";
-	char ok_p3[] = "] ";
-	
-	print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
-	print_str(ok_p1);
-	
-	print_set_color(PRINT_COLOR_GREEN, PRINT_COLOR_BLACK);
-	print_str(ok_p2);
-	
-	print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
-	print_str(ok_p3);
-	print_str(msg);
-}

src/libc/printf.c

@@ -0,0 +1,923 @@
+
+  
+///////////////////////////////////////////////////////////////////////////////
+// \author (c) Marco Paland (info@paland.com)
+//             2014-2019, PALANDesign Hannover, Germany
+//
+// \license The MIT License (MIT)
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+// \brief Tiny printf, sprintf and (v)snprintf implementation, optimized for speed on
+//        embedded systems with a very limited resources. These routines are thread
+//        safe and reentrant!
+//        Use this instead of the bloated standard/newlib printf cause these use
+//        malloc for printf (and may not be thread safe).
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <shade/platform/drivers/vga_text_mode.h> // c0repwn3r: implmenent _putchar with shade's VGA text driver
+#include <shade/util.h> // c0repwn3r
+
+#include "printf.h"
+
+// c0repwn3r: implement _putchar with shade's VGA text driver, and ANSI support
+void _putchar(char character) {
+    print_char(character);
+}
+// end: implement _putchar with shade's VGA text driver, and ANSI support
+
+// define this globally (e.g. gcc -DPRINTF_INCLUDE_CONFIG_H ...) to include the
+// printf_config.h header file
+// default: undefined
+#ifdef PRINTF_INCLUDE_CONFIG_H
+#include "printf_config.h"
+#endif
+
+
+// 'ntoa' conversion buffer size, this must be big enough to hold one converted
+// numeric number including padded zeros (dynamically created on stack)
+// default: 32 byte
+#ifndef PRINTF_NTOA_BUFFER_SIZE
+#define PRINTF_NTOA_BUFFER_SIZE    32U
+#endif
+
+// 'ftoa' conversion buffer size, this must be big enough to hold one converted
+// float number including padded zeros (dynamically created on stack)
+// default: 32 byte
+#ifndef PRINTF_FTOA_BUFFER_SIZE
+#define PRINTF_FTOA_BUFFER_SIZE    32U
+#endif
+
+// support for the floating point type (%f)
+// default: activated
+#ifndef PRINTF_DISABLE_SUPPORT_FLOAT
+#define PRINTF_SUPPORT_FLOAT
+#endif
+
+// support for exponential floating point notation (%e/%g)
+// default: activated
+#ifndef PRINTF_DISABLE_SUPPORT_EXPONENTIAL
+#define PRINTF_SUPPORT_EXPONENTIAL
+#endif
+
+// define the default floating point precision
+// default: 6 digits
+#ifndef PRINTF_DEFAULT_FLOAT_PRECISION
+#define PRINTF_DEFAULT_FLOAT_PRECISION  6U
+#endif
+
+// define the largest float suitable to print with %f
+// default: 1e9
+#ifndef PRINTF_MAX_FLOAT
+#define PRINTF_MAX_FLOAT  1e9
+#endif
+
+// support for the long long types (%llu or %p)
+// default: activated
+#ifndef PRINTF_DISABLE_SUPPORT_LONG_LONG
+#define PRINTF_SUPPORT_LONG_LONG
+#endif
+
+// support for the ptrdiff_t type (%t)
+// ptrdiff_t is normally defined in <stddef.h> as long or long long type
+// default: activated
+#ifndef PRINTF_DISABLE_SUPPORT_PTRDIFF_T
+#define PRINTF_SUPPORT_PTRDIFF_T
+#endif
+
+///////////////////////////////////////////////////////////////////////////////
+
+// internal flag definitions
+#define FLAGS_ZEROPAD   (1U <<  0U)
+#define FLAGS_LEFT      (1U <<  1U)
+#define FLAGS_PLUS      (1U <<  2U)
+#define FLAGS_SPACE     (1U <<  3U)
+#define FLAGS_HASH      (1U <<  4U)
+#define FLAGS_UPPERCASE (1U <<  5U)
+#define FLAGS_CHAR      (1U <<  6U)
+#define FLAGS_SHORT     (1U <<  7U)
+#define FLAGS_LONG      (1U <<  8U)
+#define FLAGS_LONG_LONG (1U <<  9U)
+#define FLAGS_PRECISION (1U << 10U)
+#define FLAGS_ADAPT_EXP (1U << 11U)
+
+
+// import float.h for DBL_MAX
+#if defined(PRINTF_SUPPORT_FLOAT)
+#include <float.h>
+#endif
+
+
+// output function type
+typedef void (*out_fct_type)(char character, void* buffer, size_t idx, size_t maxlen);
+
+
+// wrapper (used as buffer) for output function type
+typedef struct {
+  void  (*fct)(char character, void* arg);
+  void* arg;
+} out_fct_wrap_type;
+
+
+// internal buffer output
+static inline void _out_buffer(char character, void* buffer, size_t idx, size_t maxlen)
+{
+  if (idx < maxlen) {
+    ((char*)buffer)[idx] = character;
+  }
+}
+
+
+// internal null output
+static inline void _out_null(char character, void* buffer, size_t idx, size_t maxlen)
+{
+  (void)character; (void)buffer; (void)idx; (void)maxlen;
+}
+
+
+// internal _putchar wrapper
+static inline void _out_char(char character, void* buffer, size_t idx, size_t maxlen)
+{
+  (void)buffer; (void)idx; (void)maxlen;
+  if (character) {
+    _putchar(character);
+  }
+}
+
+
+// internal output function wrapper
+static inline void _out_fct(char character, void* buffer, size_t idx, size_t maxlen)
+{
+  (void)idx; (void)maxlen;
+  if (character) {
+    // buffer is the output fct pointer
+    ((out_fct_wrap_type*)buffer)->fct(character, ((out_fct_wrap_type*)buffer)->arg);
+  }
+}
+
+
+// internal secure strlen
+// \return The length of the string (excluding the terminating 0) limited by 'maxsize'
+static inline unsigned int _strnlen_s(const char* str, size_t maxsize)
+{
+  const char* s;
+  for (s = str; *s && maxsize--; ++s);
+  return (unsigned int)(s - str);
+}
+
+
+// internal test if char is a digit (0-9)
+// \return true if char is a digit
+static inline bool _is_digit(char ch)
+{
+  return (ch >= '0') && (ch <= '9');
+}
+
+
+// internal ASCII string to unsigned int conversion
+static unsigned int _atoi(const char** str)
+{
+  unsigned int i = 0U;
+  while (_is_digit(**str)) {
+    i = i * 10U + (unsigned int)(*((*str)++) - '0');
+  }
+  return i;
+}
+
+
+// output the specified string in reverse, taking care of any zero-padding
+static size_t _out_rev(out_fct_type out, char* buffer, size_t idx, size_t maxlen, const char* buf, size_t len, unsigned int width, unsigned int flags)
+{
+  const size_t start_idx = idx;
+
+  // pad spaces up to given width
+  if (!(flags & FLAGS_LEFT) && !(flags & FLAGS_ZEROPAD)) {
+    for (size_t i = len; i < width; i++) {
+      out(' ', buffer, idx++, maxlen);
+    }
+  }
+
+  // reverse string
+  while (len) {
+    out(buf[--len], buffer, idx++, maxlen);
+  }
+
+  // append pad spaces up to given width
+  if (flags & FLAGS_LEFT) {
+    while (idx - start_idx < width) {
+      out(' ', buffer, idx++, maxlen);
+    }
+  }
+
+  return idx;
+}
+
+
+// internal itoa format
+static size_t _ntoa_format(out_fct_type out, char* buffer, size_t idx, size_t maxlen, char* buf, size_t len, bool negative, unsigned int base, unsigned int prec, unsigned int width, unsigned int flags)
+{
+  // pad leading zeros
+  if (!(flags & FLAGS_LEFT)) {
+    if (width && (flags & FLAGS_ZEROPAD) && (negative || (flags & (FLAGS_PLUS | FLAGS_SPACE)))) {
+      width--;
+    }
+    while ((len < prec) && (len < PRINTF_NTOA_BUFFER_SIZE)) {
+      buf[len++] = '0';
+    }
+    while ((flags & FLAGS_ZEROPAD) && (len < width) && (len < PRINTF_NTOA_BUFFER_SIZE)) {
+      buf[len++] = '0';
+    }
+  }
+
+  // handle hash
+  if (flags & FLAGS_HASH) {
+    if (!(flags & FLAGS_PRECISION) && len && ((len == prec) || (len == width))) {
+      len--;
+      if (len && (base == 16U)) {
+        len--;
+      }
+    }
+    if ((base == 16U) && !(flags & FLAGS_UPPERCASE) && (len < PRINTF_NTOA_BUFFER_SIZE)) {
+      buf[len++] = 'x';
+    }
+    else if ((base == 16U) && (flags & FLAGS_UPPERCASE) && (len < PRINTF_NTOA_BUFFER_SIZE)) {
+      buf[len++] = 'X';
+    }
+    else if ((base == 2U) && (len < PRINTF_NTOA_BUFFER_SIZE)) {
+      buf[len++] = 'b';
+    }
+    if (len < PRINTF_NTOA_BUFFER_SIZE) {
+      buf[len++] = '0';
+    }
+  }
+
+  if (len < PRINTF_NTOA_BUFFER_SIZE) {
+    if (negative) {
+      buf[len++] = '-';
+    }
+    else if (flags & FLAGS_PLUS) {
+      buf[len++] = '+';  // ignore the space if the '+' exists
+    }
+    else if (flags & FLAGS_SPACE) {
+      buf[len++] = ' ';
+    }
+  }
+
+  return _out_rev(out, buffer, idx, maxlen, buf, len, width, flags);
+}
+
+
+// internal itoa for 'long' type
+static size_t _ntoa_long(out_fct_type out, char* buffer, size_t idx, size_t maxlen, unsigned long value, bool negative, unsigned long base, unsigned int prec, unsigned int width, unsigned int flags)
+{
+  char buf[PRINTF_NTOA_BUFFER_SIZE];
+  size_t len = 0U;
+
+  // no hash for 0 values
+  if (!value) {
+    flags &= ~FLAGS_HASH;
+  }
+
+  // write if precision != 0 and value is != 0
+  if (!(flags & FLAGS_PRECISION) || value) {
+    do {
+      const char digit = (char)(value % base);
+      buf[len++] = digit < 10 ? '0' + digit : (flags & FLAGS_UPPERCASE ? 'A' : 'a') + digit - 10;
+      value /= base;
+    } while (value && (len < PRINTF_NTOA_BUFFER_SIZE));
+  }
+
+  return _ntoa_format(out, buffer, idx, maxlen, buf, len, negative, (unsigned int)base, prec, width, flags);
+}
+
+
+// internal itoa for 'long long' type
+#if defined(PRINTF_SUPPORT_LONG_LONG)
+static size_t _ntoa_long_long(out_fct_type out, char* buffer, size_t idx, size_t maxlen, unsigned long long value, bool negative, unsigned long long base, unsigned int prec, unsigned int width, unsigned int flags)
+{
+  char buf[PRINTF_NTOA_BUFFER_SIZE];
+  size_t len = 0U;
+
+  // no hash for 0 values
+  if (!value) {
+    flags &= ~FLAGS_HASH;
+  }
+
+  // write if precision != 0 and value is != 0
+  if (!(flags & FLAGS_PRECISION) || value) {
+    do {
+      const char digit = (char)(value % base);
+      buf[len++] = digit < 10 ? '0' + digit : (flags & FLAGS_UPPERCASE ? 'A' : 'a') + digit - 10;
+      value /= base;
+    } while (value && (len < PRINTF_NTOA_BUFFER_SIZE));
+  }
+
+  return _ntoa_format(out, buffer, idx, maxlen, buf, len, negative, (unsigned int)base, prec, width, flags);
+}
+#endif  // PRINTF_SUPPORT_LONG_LONG
+
+
+#if defined(PRINTF_SUPPORT_FLOAT)
+
+#if defined(PRINTF_SUPPORT_EXPONENTIAL)
+// forward declaration so that _ftoa can switch to exp notation for values > PRINTF_MAX_FLOAT
+static size_t _etoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, double value, unsigned int prec, unsigned int width, unsigned int flags);
+#endif
+
+
+// internal ftoa for fixed decimal floating point
+static size_t _ftoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, double value, unsigned int prec, unsigned int width, unsigned int flags)
+{
+  char buf[PRINTF_FTOA_BUFFER_SIZE];
+  size_t len  = 0U;
+  double diff = 0.0;
+
+  // powers of 10
+  static const double pow10[] = { 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000 };
+
+  // test for special values
+  if (value != value)
+    return _out_rev(out, buffer, idx, maxlen, "nan", 3, width, flags);
+  if (value < -DBL_MAX)
+    return _out_rev(out, buffer, idx, maxlen, "fni-", 4, width, flags);
+  if (value > DBL_MAX)
+    return _out_rev(out, buffer, idx, maxlen, (flags & FLAGS_PLUS) ? "fni+" : "fni", (flags & FLAGS_PLUS) ? 4U : 3U, width, flags);
+
+  // test for very large values
+  // standard printf behavior is to print EVERY whole number digit -- which could be 100s of characters overflowing your buffers == bad
+  if ((value > PRINTF_MAX_FLOAT) || (value < -PRINTF_MAX_FLOAT)) {
+#if defined(PRINTF_SUPPORT_EXPONENTIAL)
+    return _etoa(out, buffer, idx, maxlen, value, prec, width, flags);
+#else
+    return 0U;
+#endif
+  }
+
+  // test for negative
+  bool negative = false;
+  if (value < 0) {
+    negative = true;
+    value = 0 - value;
+  }
+
+  // set default precision, if not set explicitly
+  if (!(flags & FLAGS_PRECISION)) {
+    prec = PRINTF_DEFAULT_FLOAT_PRECISION;
+  }
+  // limit precision to 9, cause a prec >= 10 can lead to overflow errors
+  while ((len < PRINTF_FTOA_BUFFER_SIZE) && (prec > 9U)) {
+    buf[len++] = '0';
+    prec--;
+  }
+
+  int whole = (int)value;
+  double tmp = (value - whole) * pow10[prec];
+  unsigned long frac = (unsigned long)tmp;
+  diff = tmp - frac;
+
+  if (diff > 0.5) {
+    ++frac;
+    // handle rollover, e.g. case 0.99 with prec 1 is 1.0
+    if (frac >= pow10[prec]) {
+      frac = 0;
+      ++whole;
+    }
+  }
+  else if (diff < 0.5) {
+  }
+  else if ((frac == 0U) || (frac & 1U)) {
+    // if halfway, round up if odd OR if last digit is 0
+    ++frac;
+  }
+
+  if (prec == 0U) {
+    diff = value - (double)whole;
+    if ((!(diff < 0.5) || (diff > 0.5)) && (whole & 1)) {
+      // exactly 0.5 and ODD, then round up
+      // 1.5 -> 2, but 2.5 -> 2
+      ++whole;
+    }
+  }
+  else {
+    unsigned int count = prec;
+    // now do fractional part, as an unsigned number
+    while (len < PRINTF_FTOA_BUFFER_SIZE) {
+      --count;
+      buf[len++] = (char)(48U + (frac % 10U));
+      if (!(frac /= 10U)) {
+        break;
+      }
+    }
+    // add extra 0s
+    while ((len < PRINTF_FTOA_BUFFER_SIZE) && (count-- > 0U)) {
+      buf[len++] = '0';
+    }
+    if (len < PRINTF_FTOA_BUFFER_SIZE) {
+      // add decimal
+      buf[len++] = '.';
+    }
+  }
+
+  // do whole part, number is reversed
+  while (len < PRINTF_FTOA_BUFFER_SIZE) {
+    buf[len++] = (char)(48 + (whole % 10));
+    if (!(whole /= 10)) {
+      break;
+    }
+  }
+
+  // pad leading zeros
+  if (!(flags & FLAGS_LEFT) && (flags & FLAGS_ZEROPAD)) {
+    if (width && (negative || (flags & (FLAGS_PLUS | FLAGS_SPACE)))) {
+      width--;
+    }
+    while ((len < width) && (len < PRINTF_FTOA_BUFFER_SIZE)) {
+      buf[len++] = '0';
+    }
+  }
+
+  if (len < PRINTF_FTOA_BUFFER_SIZE) {
+    if (negative) {
+      buf[len++] = '-';
+    }
+    else if (flags & FLAGS_PLUS) {
+      buf[len++] = '+';  // ignore the space if the '+' exists
+    }
+    else if (flags & FLAGS_SPACE) {
+      buf[len++] = ' ';
+    }
+  }
+
+  return _out_rev(out, buffer, idx, maxlen, buf, len, width, flags);
+}
+
+
+#if defined(PRINTF_SUPPORT_EXPONENTIAL)
+// internal ftoa variant for exponential floating-point type, contributed by Martijn Jasperse <m.jasperse@gmail.com>
+static size_t _etoa(out_fct_type out, char* buffer, size_t idx, size_t maxlen, double value, unsigned int prec, unsigned int width, unsigned int flags)
+{
+  // check for NaN and special values
+  if ((value != value) || (value > DBL_MAX) || (value < -DBL_MAX)) {
+    return _ftoa(out, buffer, idx, maxlen, value, prec, width, flags);
+  }
+
+  // determine the sign
+  const bool negative = value < 0;
+  if (negative) {
+    value = -value;
+  }
+
+  // default precision
+  if (!(flags & FLAGS_PRECISION)) {
+    prec = PRINTF_DEFAULT_FLOAT_PRECISION;
+  }
+
+  // determine the decimal exponent
+  // based on the algorithm by David Gay (https://www.ampl.com/netlib/fp/dtoa.c)
+  union {
+    uint64_t U;
+    double   F;
+  } conv;
+
+  conv.F = value;
+  int exp2 = (int)((conv.U >> 52U) & 0x07FFU) - 1023;           // effectively log2
+  conv.U = (conv.U & ((1ULL << 52U) - 1U)) | (1023ULL << 52U);  // drop the exponent so conv.F is now in [1,2)
+  // now approximate log10 from the log2 integer part and an expansion of ln around 1.5
+  int expval = (int)(0.1760912590558 + exp2 * 0.301029995663981 + (conv.F - 1.5) * 0.289529654602168);
+  // now we want to compute 10^expval but we want to be sure it won't overflow
+  exp2 = (int)(expval * 3.321928094887362 + 0.5);
+  const double z  = expval * 2.302585092994046 - exp2 * 0.6931471805599453;
+  const double z2 = z * z;
+  conv.U = (uint64_t)(exp2 + 1023) << 52U;
+  // compute exp(z) using continued fractions, see https://en.wikipedia.org/wiki/Exponential_function#Continued_fractions_for_ex
+  conv.F *= 1 + 2 * z / (2 - z + (z2 / (6 + (z2 / (10 + z2 / 14)))));
+  // correct for rounding errors
+  if (value < conv.F) {
+    expval--;
+    conv.F /= 10;
+  }
+
+  // the exponent format is "%+03d" and largest value is "307", so set aside 4-5 characters
+  unsigned int minwidth = ((expval < 100) && (expval > -100)) ? 4U : 5U;
+
+  // in "%g" mode, "prec" is the number of *significant figures* not decimals
+  if (flags & FLAGS_ADAPT_EXP) {
+    // do we want to fall-back to "%f" mode?
+    if ((value >= 1e-4) && (value < 1e6)) {
+      if ((int)prec > expval) {
+        prec = (unsigned)((int)prec - expval - 1);
+      }
+      else {
+        prec = 0;
+      }
+      flags |= FLAGS_PRECISION;   // make sure _ftoa respects precision
+      // no characters in exponent
+      minwidth = 0U;
+      expval   = 0;
+    }
+    else {
+      // we use one sigfig for the whole part
+      if ((prec > 0) && (flags & FLAGS_PRECISION)) {
+        --prec;
+      }
+    }
+  }
+
+  // will everything fit?
+  unsigned int fwidth = width;
+  if (width > minwidth) {
+    // we didn't fall-back so subtract the characters required for the exponent
+    fwidth -= minwidth;
+  } else {
+    // not enough characters, so go back to default sizing
+    fwidth = 0U;
+  }
+  if ((flags & FLAGS_LEFT) && minwidth) {
+    // if we're padding on the right, DON'T pad the floating part
+    fwidth = 0U;
+  }
+
+  // rescale the float value
+  if (expval) {
+    value /= conv.F;
+  }
+
+  // output the floating part
+  const size_t start_idx = idx;
+  idx = _ftoa(out, buffer, idx, maxlen, negative ? -value : value, prec, fwidth, flags & ~FLAGS_ADAPT_EXP);
+
+  // output the exponent part
+  if (minwidth) {
+    // output the exponential symbol
+    out((flags & FLAGS_UPPERCASE) ? 'E' : 'e', buffer, idx++, maxlen);
+    // output the exponent value
+    idx = _ntoa_long(out, buffer, idx, maxlen, (expval < 0) ? -expval : expval, expval < 0, 10, 0, minwidth-1, FLAGS_ZEROPAD | FLAGS_PLUS);
+    // might need to right-pad spaces
+    if (flags & FLAGS_LEFT) {
+      while (idx - start_idx < width) out(' ', buffer, idx++, maxlen);
+    }
+  }
+  return idx;
+}
+#endif  // PRINTF_SUPPORT_EXPONENTIAL
+#endif  // PRINTF_SUPPORT_FLOAT
+
+
+// internal vsnprintf
+static int _vsnprintf(out_fct_type out, char* buffer, const size_t maxlen, const char* format, va_list va)
+{
+  unsigned int flags, width, precision, n;
+  size_t idx = 0U;
+
+  if (!buffer) {
+    // use null output function
+    out = _out_null;
+  }
+
+  while (*format)
+  {
+    // format specifier?  %[flags][width][.precision][length]
+    if (*format != '%') {
+      // no
+      out(*format, buffer, idx++, maxlen);
+      format++;
+      continue;
+    }
+    else {
+      // yes, evaluate it
+      format++;
+    }
+
+    // evaluate flags
+    flags = 0U;
+    do {
+      switch (*format) {
+        case '0': flags |= FLAGS_ZEROPAD; format++; n = 1U; break;
+        case '-': flags |= FLAGS_LEFT;    format++; n = 1U; break;
+        case '+': flags |= FLAGS_PLUS;    format++; n = 1U; break;
+        case ' ': flags |= FLAGS_SPACE;   format++; n = 1U; break;
+        case '#': flags |= FLAGS_HASH;    format++; n = 1U; break;
+        default :                                   n = 0U; break;
+      }
+    } while (n);
+
+    // evaluate width field
+    width = 0U;
+    if (_is_digit(*format)) {
+      width = _atoi(&format);
+    }
+    else if (*format == '*') {
+      const int w = va_arg(va, int);
+      if (w < 0) {
+        flags |= FLAGS_LEFT;    // reverse padding
+        width = (unsigned int)-w;
+      }
+      else {
+        width = (unsigned int)w;
+      }
+      format++;
+    }
+
+    // evaluate precision field
+    precision = 0U;
+    if (*format == '.') {
+      flags |= FLAGS_PRECISION;
+      format++;
+      if (_is_digit(*format)) {
+        precision = _atoi(&format);
+      }
+      else if (*format == '*') {
+        const int prec = (int)va_arg(va, int);
+        precision = prec > 0 ? (unsigned int)prec : 0U;
+        format++;
+      }
+    }
+
+    // evaluate length field
+    switch (*format) {
+      case 'l' :
+        flags |= FLAGS_LONG;
+        format++;
+        if (*format == 'l') {
+          flags |= FLAGS_LONG_LONG;
+          format++;
+        }
+        break;
+      case 'h' :
+        flags |= FLAGS_SHORT;
+        format++;
+        if (*format == 'h') {
+          flags |= FLAGS_CHAR;
+          format++;
+        }
+        break;
+#if defined(PRINTF_SUPPORT_PTRDIFF_T)
+      case 't' :
+        flags |= (sizeof(ptrdiff_t) == sizeof(long) ? FLAGS_LONG : FLAGS_LONG_LONG);
+        format++;
+        break;
+#endif
+      case 'j' :
+        flags |= (sizeof(intmax_t) == sizeof(long) ? FLAGS_LONG : FLAGS_LONG_LONG);
+        format++;
+        break;
+      case 'z' :
+        flags |= (sizeof(size_t) == sizeof(long) ? FLAGS_LONG : FLAGS_LONG_LONG);
+        format++;
+        break;
+      default :
+        break;
+    }
+
+    // evaluate specifier
+    switch (*format) {
+      case 'd' :
+      case 'i' :
+      case 'u' :
+      case 'x' :
+      case 'X' :
+      case 'o' :
+      case 'b' : {
+        // set the base
+        unsigned int base;
+        if (*format == 'x' || *format == 'X') {
+          base = 16U;
+        }
+        else if (*format == 'o') {
+          base =  8U;
+        }
+        else if (*format == 'b') {
+          base =  2U;
+        }
+        else {
+          base = 10U;
+          flags &= ~FLAGS_HASH;   // no hash for dec format
+        }
+        // uppercase
+        if (*format == 'X') {
+          flags |= FLAGS_UPPERCASE;
+        }
+
+        // no plus or space flag for u, x, X, o, b
+        if ((*format != 'i') && (*format != 'd')) {
+          flags &= ~(FLAGS_PLUS | FLAGS_SPACE);
+        }
+
+        // ignore '0' flag when precision is given
+        if (flags & FLAGS_PRECISION) {
+          flags &= ~FLAGS_ZEROPAD;
+        }
+
+        // convert the integer
+        if ((*format == 'i') || (*format == 'd')) {
+          // signed
+          if (flags & FLAGS_LONG_LONG) {
+#if defined(PRINTF_SUPPORT_LONG_LONG)
+            const long long value = va_arg(va, long long);
+            idx = _ntoa_long_long(out, buffer, idx, maxlen, (unsigned long long)(value > 0 ? value : 0 - value), value < 0, base, precision, width, flags);
+#endif
+          }
+          else if (flags & FLAGS_LONG) {
+            const long value = va_arg(va, long);
+            idx = _ntoa_long(out, buffer, idx, maxlen, (unsigned long)(value > 0 ? value : 0 - value), value < 0, base, precision, width, flags);
+          }
+          else {
+            const int value = (flags & FLAGS_CHAR) ? (char)va_arg(va, int) : (flags & FLAGS_SHORT) ? (short int)va_arg(va, int) : va_arg(va, int);
+            idx = _ntoa_long(out, buffer, idx, maxlen, (unsigned int)(value > 0 ? value : 0 - value), value < 0, base, precision, width, flags);
+          }
+        }
+        else {
+          // unsigned
+          if (flags & FLAGS_LONG_LONG) {
+#if defined(PRINTF_SUPPORT_LONG_LONG)
+            idx = _ntoa_long_long(out, buffer, idx, maxlen, va_arg(va, unsigned long long), false, base, precision, width, flags);
+#endif
+          }
+          else if (flags & FLAGS_LONG) {
+            idx = _ntoa_long(out, buffer, idx, maxlen, va_arg(va, unsigned long), false, base, precision, width, flags);
+          }
+          else {
+            const unsigned int value = (flags & FLAGS_CHAR) ? (unsigned char)va_arg(va, unsigned int) : (flags & FLAGS_SHORT) ? (unsigned short int)va_arg(va, unsigned int) : va_arg(va, unsigned int);
+            idx = _ntoa_long(out, buffer, idx, maxlen, value, false, base, precision, width, flags);
+          }
+        }
+        format++;
+        break;
+      }
+#if defined(PRINTF_SUPPORT_FLOAT)
+      case 'f' :
+      case 'F' :
+        if (*format == 'F') flags |= FLAGS_UPPERCASE;
+        idx = _ftoa(out, buffer, idx, maxlen, va_arg(va, double), precision, width, flags);
+        format++;
+        break;
+#if defined(PRINTF_SUPPORT_EXPONENTIAL)
+      case 'e':
+      case 'E':
+      case 'g':
+      case 'G':
+        if ((*format == 'g')||(*format == 'G')) flags |= FLAGS_ADAPT_EXP;
+        if ((*format == 'E')||(*format == 'G')) flags |= FLAGS_UPPERCASE;
+        idx = _etoa(out, buffer, idx, maxlen, va_arg(va, double), precision, width, flags);
+        format++;
+        break;
+#endif  // PRINTF_SUPPORT_EXPONENTIAL
+#endif  // PRINTF_SUPPORT_FLOAT
+      case 'c' : {
+        unsigned int l = 1U;
+        // pre padding
+        if (!(flags & FLAGS_LEFT)) {
+          while (l++ < width) {
+            out(' ', buffer, idx++, maxlen);
+          }
+        }
+        // char output
+        out((char)va_arg(va, int), buffer, idx++, maxlen);
+        // post padding
+        if (flags & FLAGS_LEFT) {
+          while (l++ < width) {
+            out(' ', buffer, idx++, maxlen);
+          }
+        }
+        format++;
+        break;
+      }
+
+      case 's' : {
+        const char* p = va_arg(va, char*);
+        unsigned int l = _strnlen_s(p, precision ? precision : (size_t)-1);
+        // pre padding
+        if (flags & FLAGS_PRECISION) {
+          l = (l < precision ? l : precision);
+        }
+        if (!(flags & FLAGS_LEFT)) {
+          while (l++ < width) {
+            out(' ', buffer, idx++, maxlen);
+          }
+        }
+        // string output
+        while ((*p != 0) && (!(flags & FLAGS_PRECISION) || precision--)) {
+          out(*(p++), buffer, idx++, maxlen);
+        }
+        // post padding
+        if (flags & FLAGS_LEFT) {
+          while (l++ < width) {
+            out(' ', buffer, idx++, maxlen);
+          }
+        }
+        format++;
+        break;
+      }
+
+      case 'p' : {
+        width = sizeof(void*) * 2U;
+        flags |= FLAGS_ZEROPAD | FLAGS_UPPERCASE;
+#if defined(PRINTF_SUPPORT_LONG_LONG)
+        const bool is_ll = sizeof(uintptr_t) == sizeof(long long);
+        if (is_ll) {
+          idx = _ntoa_long_long(out, buffer, idx, maxlen, (uintptr_t)va_arg(va, void*), false, 16U, precision, width, flags);
+        }
+        else {
+#endif
+          idx = _ntoa_long(out, buffer, idx, maxlen, (unsigned long)((uintptr_t)va_arg(va, void*)), false, 16U, precision, width, flags);
+#if defined(PRINTF_SUPPORT_LONG_LONG)
+        }
+#endif
+        format++;
+        break;
+      }
+
+      case '%' :
+        out('%', buffer, idx++, maxlen);
+        format++;
+        break;
+
+      default :
+        out(*format, buffer, idx++, maxlen);
+        format++;
+        break;
+    }
+  }
+
+  // termination
+  out((char)0, buffer, idx < maxlen ? idx : maxlen - 1U, maxlen);
+
+  // return written chars without terminating \0
+  return (int)idx;
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+
+int printf_(const char* format, ...)
+{
+  va_list va;
+  va_start(va, format);
+  char buffer[1];
+  const int ret = _vsnprintf(_out_char, buffer, (size_t)-1, format, va);
+  va_end(va);
+  return ret;
+}
+
+
+int sprintf_(char* buffer, const char* format, ...)
+{
+  va_list va;
+  va_start(va, format);
+  const int ret = _vsnprintf(_out_buffer, buffer, (size_t)-1, format, va);
+  va_end(va);
+  return ret;
+}
+
+
+int snprintf_(char* buffer, size_t count, const char* format, ...)
+{
+  va_list va;
+  va_start(va, format);
+  const int ret = _vsnprintf(_out_buffer, buffer, count, format, va);
+  va_end(va);
+  return ret;
+}
+
+
+int vprintf_(const char* format, va_list va)
+{
+  char buffer[1];
+  return _vsnprintf(_out_char, buffer, (size_t)-1, format, va);
+}
+
+
+int vsnprintf_(char* buffer, size_t count, const char* format, va_list va)
+{
+  return _vsnprintf(_out_buffer, buffer, count, format, va);
+}
+
+
+int fctprintf(void (*out)(char character, void* arg), void* arg, const char* format, ...)
+{
+  va_list va;
+  va_start(va, format);
+  const out_fct_wrap_type out_fct_wrap = { out, arg };
+  const int ret = _vsnprintf(_out_fct, (char*)(uintptr_t)&out_fct_wrap, (size_t)-1, format, va);
+  va_end(va);
+  return ret;
+}