Add FILE struct

13 files changed, 223 insertions, 141 deletions

diff --git a/devices/uart_16550.c b/devices/uart_16550.c
index 22f33ad..40ac594 100644
--- a/devices/uart_16550.c
+++ b/devices/uart_16550.c
@@ -1,4 +1,5 @@
 #include "uart_16550.h"
+#include <stddef.h>
 #include <sys/io.h>
 
 enum uart_16550_offset {
@@ -43,67 +44,74 @@ enum LineStatus {
 };
 
 int
-uart_init(enum UART port)
-{
-  outb(0x00, port + 1); // Disable all interrupts
-  outb(0x80, port + 3); // Enable DLAB (set baud rate divisor)
-  outb(0x03, port + 0); // Set divisor to 3 (lo byte) 38400 baud
-  outb(0x00, port + 1); //                  (hi byte)
-  outb(0x03, port + 3); // 8 bits, no parity, one stop bit
-  outb(0xc7, port + 2); // Enable FIFO, clear them, with 14-byte threshold
-  outb(0x0b, port + 4); // IRQs enabled, RTS/DSR set
-  outb(0x1e, port + 4); // Set in loopback mode, test the serial chip
-  outb(0xae, port + 0); // Test serial chip (send byte 0xAE and check if serial
-                        // returns same byte)
-
-  // Check if serial is faulty (i.e: not same byte as sent)
-  if (inb(port + 0) != 0xae) {
-    return 1;
-  }
-
-  // If serial is not faulty set it in normal operation mode
-  // (not-loopback with IRQs enabled and OUT#1 and OUT#2 bits enabled)
-  outb(0x0f, port + 4);
-  return 0;
-}
-
-int
 uart_thre(enum UART port)
 {
   return inb(port + LineStatus) & THRE;
 }
 
 void
-uart_write(enum UART port, char a)
+uart_write(const FILE *self, char a)
 {
-  while (uart_thre(port) == 0)
-    ;
-  outb(a, port);
+  while (uart_thre(self->id) == 0) {}
+  outb(a, self->id);
 
   if (a == '\n') {
-    while (uart_thre(port) == 0)
-      ;
-    outb('\r', port);
+    while (uart_thre(self->id) == 0) {}
+    outb('\r', self->id);
   }
 }
 
 int
-uart_puts(enum UART port, const char *string, int length)
+uart_puts(const FILE *self, const char *string, int length)
 {
   int written = 0;
 
   if (length == -1)
     while (*string != '\0') {
-      uart_write(port, *string);
+      uart_write(self, *string);
       ++string;
       ++written;
     }
 
   else
     for (int i = 0; i < length; ++i) {
-      uart_write(port, string[i]);
+      uart_write(self, string[i]);
       ++written;
     }
 
   return written;
 }
+
+void
+uart_flush(const FILE *self)
+{
+}
+
+FILE uart_stream;
+
+FILE *
+uart_init(enum UART port)
+{
+  outb(0x00, port + 1); // Disable all interrupts
+  outb(0x80, port + 3); // Enable DLAB (set baud rate divisor)
+  outb(0x03, port + 0); // Set divisor to 3 (lo byte) 38400 baud
+  outb(0x00, port + 1); //                  (hi byte)
+  outb(0x03, port + 3); // 8 bits, no parity, one stop bit
+  outb(0xc7, port + 2); // Enable FIFO, clear them, with 14-byte threshold
+  outb(0x0b, port + 4); // IRQs enabled, RTS/DSR set
+  outb(0x1e, port + 4); // Set in loopback mode, test the serial chip
+  outb(0xae, port + 0); // Test serial chip (send byte 0xAE and check if serial
+                        // returns same byte)
+
+  // Check if serial is faulty (i.e: not same byte as sent)
+  if (inb(port + 0) != 0xae) { return NULL; }
+
+  // If serial is not faulty set it in normal operation mode
+  // (not-loopback with IRQs enabled and OUT#1 and OUT#2 bits enabled)
+  outb(0x0f, port + 4);
+  uart_stream.id = port;
+  uart_stream.putc = &uart_write;
+  uart_stream.puts = &uart_puts;
+  uart_stream.flush = &uart_flush;
+  return &uart_stream;
+}
diff --git a/devices/uart_16550.h b/devices/uart_16550.h
index bb219cc..5e5ee13 100644
--- a/devices/uart_16550.h
+++ b/devices/uart_16550.h
@@ -1,5 +1,7 @@
 #pragma once
 
+#include <stdio.h>
+
 enum UART {
   COM1 = 0x3f8,
   COM2 = 0x2f8,
@@ -11,6 +13,6 @@ enum UART {
   COM8 = 0x4E8,
 };
 
-int uart_init(enum UART port);
-void uart_write(enum UART port, char a);
-int uart_puts(enum UART port, const char *string, int length);
+FILE *uart_init(enum UART port);
+// void uart_write(enum UART port, char a);
+// int uart_puts(enum UART port, const char *string, int length);
diff --git a/devices/vga.c b/devices/vga.c
index 39370ba..12ac880 100644
--- a/devices/vga.c
+++ b/devices/vga.c
@@ -55,31 +55,9 @@ vga_update_cursor()
   outb((pos >> 8) & 0xff, cga_dat_port);
 }
 
-// *** Text Mode ***
-void
-vga_init()
-{
-  buffer = (struct VGAEntry *)0xc03ff000;
-  vga_enable_cursor(14, 15);
-  vga_clear(VGA_COLOR_LIGHT_BLUE, VGA_COLOR_LIGHT_GREY);
-}
-
-void
-vga_clear(enum vga_color foreground, enum vga_color background)
-{
-  for (int y = 0; y < height; ++y)
-    for (int x = 0; x < width; ++x) {
-      const int index = y * width + x;
-      buffer[index].text = ' ';
-      buffer[index].foreground = foreground;
-      buffer[index].background = background;
-    }
-  col = row = 0;
-  vga_update_cursor();
-}
-
+// *** Text Mode Output ***
 void
-vga_putc(char a)
+vga_putc(const FILE *self, char a)
 {
   switch (a) {
   case '\n':
@@ -117,16 +95,58 @@ vga_putc(char a)
   }
 }
 
-void
-vga_puts(const char *string, int len)
+int
+vga_puts(const FILE *self, const char *string, int len)
 {
-
+  int written = 0;
   if (len == -1)
     while (*string != '\0') {
-      vga_putc(*string);
+      vga_putc(self, *string);
       ++string;
+      ++written;
     }
 
   else
-    for (int i = 0; i < len; ++i) { vga_putc(string[i]); }
+    for (int i = 0; i < len; ++i) {
+      vga_putc(self, string[i]);
+      ++written;
+    }
+  return written;
+}
+
+void
+vga_flush(const FILE *self)
+{
+  vga_update_cursor();
+}
+
+// *** Text Mode ***
+FILE vga_stream;
+
+FILE *
+vga_init()
+{
+  buffer = (struct VGAEntry *)0xc03ff000;
+  vga_enable_cursor(14, 15);
+  vga_clear(VGA_COLOR_LIGHT_BLUE, VGA_COLOR_LIGHT_GREY);
+
+  vga_stream.id = 0;
+  vga_stream.putc = &vga_putc;
+  vga_stream.puts = &vga_puts;
+  vga_stream.flush = &vga_flush;
+  return &vga_stream;
+}
+
+void
+vga_clear(enum vga_color foreground, enum vga_color background)
+{
+  for (int y = 0; y < height; ++y)
+    for (int x = 0; x < width; ++x) {
+      const int index = y * width + x;
+      buffer[index].text = ' ';
+      buffer[index].foreground = foreground;
+      buffer[index].background = background;
+    }
+  col = row = 0;
+  vga_update_cursor();
 }
diff --git a/devices/vga.h b/devices/vga.h
index daaa482..d9dfd44 100644
--- a/devices/vga.h
+++ b/devices/vga.h
@@ -1,5 +1,7 @@
 #pragma once
 
+#include <stdio.h>
+
 /** Hardware text mode color constants. */
 enum vga_color {
   VGA_COLOR_BLACK = 0,
@@ -20,11 +22,11 @@ enum vga_color {
   VGA_COLOR_WHITE = 15,
 };
 
-void vga_init();
+FILE *vga_init();
 void vga_clear(enum vga_color foreground, enum vga_color background);
 
-void vga_putc(char a);
-void vga_puts(const char *string, int len);
+// void vga_putc(char a);
+// void vga_puts(const char *string, int len);
 
 // void vga_enable_cursor(unsigned char start, unsigned char end);
 // void vga_disable_cursor();
diff --git a/doc.src/devices.rst b/doc.src/devices.rst
index 7c8b41d..13bc2f0 100644
--- a/doc.src/devices.rst
+++ b/doc.src/devices.rst
@@ -10,6 +10,7 @@ Text mode
 osdev wiki: `Text UI <https://wiki.osdev.org/Text_mode>`_
 
 .. c:autodoc:: ../devices/vga.h
+   :clang: -isystem/usr/lib/gcc/i686-elf/12.2.0/include
 
 PS/2 Controller
 ===============
@@ -30,4 +31,5 @@ Programmable Interrupt Controller
 UART
 ====
 .. c:autodoc:: ../devices/uart_16550.h
+   :clang: -isystem/usr/lib/gcc/i686-elf/12.2.0/include
 
diff --git a/doc.src/libk.rst b/doc.src/libk.rst
index 7c30f41..078198c 100644
--- a/doc.src/libk.rst
+++ b/doc.src/libk.rst
@@ -7,11 +7,14 @@ libk is the kernel's C standard library implementation.
 stdio.h
 =======
 .. c:autodoc:: ../lib/stdio.h
+   :clang: -isystem/usr/lib/gcc/i686-elf/12.2.0/include
 
 stdlib.h
 ========
 .. c:autodoc:: ../lib/stdlib.h
+   :clang: -isystem/usr/lib/gcc/i686-elf/12.2.0/include
 
 string.h
 ========
 .. c:autodoc:: ../lib/string.h
+   :clang: -isystem/usr/lib/gcc/i686-elf/12.2.0/include
diff --git a/lib/Makefile b/lib/Makefile
index 66181c8..f564ee0 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -2,7 +2,7 @@ include ../Makefile.config
 
 CCFLAGS += -I. -I..
 
-libk.SRCS = stdio/printf.c \
+libk.SRCS = stdio/printf.c stdio/fprintf.c stdio/vfprintf.c \
             stdlib/memcpy.c stdlib/memset.c \
             string/itoa.c
 
diff --git a/lib/stdio.h b/lib/stdio.h
index 201cce1..4711a29 100644
--- a/lib/stdio.h
+++ b/lib/stdio.h
@@ -1,6 +1,38 @@
 #pragma once
 
+#include <stdarg.h>
+
+/** An object type used for streams */
+typedef struct FILE_t {
+  int id;
+  /** Functions that prints a character to the stream */
+  void (*putc)(const struct FILE_t *, char);
+  /** Function that prints a string to the stream */
+  int (*puts)(const struct FILE_t *, const char *, int);
+  /** Flush all buffers */
+  void (*flush)(const struct FILE_t *);
+} FILE;
+
+/** A FILE value corresponding to stdin, the keyboard buffer */
+extern FILE *stdin;
+/** A FILE value corresponding to stdout, the display */
+extern FILE *stdout;
+/** A FILE value corresponding to stderr, the uart */
+extern FILE *stderr;
+
 /**
- * Supports %s (string), %d (decimal), %u (unsigned), %x (hexadecimal)
+ * Write the formatted string to stdout
+ *
+ * Supports ``%s`` (string), ``%d`` (decimal), ``%u`` (unsigned), ``%x`` (hexadecimal)
  */
 int printf(const char *restrict format, ...);
+
+/**
+ * Write the formatted string to stream; see printf
+ */
+int fprintf(FILE *restrict stream, const char *restrict format, ...);
+
+/**
+ * Write the formatted string to stream; see printf
+ */
+int vfprintf(FILE *restrict stream, const char *restrict format, va_list ap);
diff --git a/lib/stdio/fprintf.c b/lib/stdio/fprintf.c
new file mode 100644
index 0000000..9a96dc6
--- /dev/null
+++ b/lib/stdio/fprintf.c
@@ -0,0 +1,11 @@
+#include <stdio.h>
+
+int
+fprintf(FILE *restrict stream, const char *restrict format, ...)
+{
+  va_list ap;
+  va_start(ap, format);
+  int c = vfprintf(stream, format, ap);
+  va_end(ap);
+  return c;
+}
diff --git a/lib/stdio/printf.c b/lib/stdio/printf.c
index ae4d5b1..4efc1ac 100644
--- a/lib/stdio/printf.c
+++ b/lib/stdio/printf.c
@@ -1,70 +1,11 @@
-#include <stdarg.h>
 #include <stdio.h>
-#include <string.h>
-
-#include <devices/uart_16550.h>
-#include <devices/vga.h>
-
-static char buffer[3 * sizeof(int) + 2];
 
 int
 printf(const char *restrict format, ...)
 {
-  int written = 0;
-  va_list params;
-  va_start(params, format);
-
-  int s = 0;
-  int l = 0;
-  for (int i = 0; format[i] != '\0'; ++i) {
-    if (format[i] == '%') {
-      written += uart_puts(COM1, &format[s], l);
-      vga_puts(&format[s], l);
-      s = i + 2;
-      ++i;
-
-      switch (format[i]) {
-      case 's': {
-        const char *arg = va_arg(params, const char *);
-        written += uart_puts(COM1, arg, -1);
-        vga_puts(arg, -1);
-      } break;
-      case 'c': {
-        const int arg = va_arg(params, int);
-        uart_write(COM1, arg);
-        vga_putc(arg);
-        ++written;
-      } break;
-      case 'd': {
-        const char *arg = itoa(buffer, va_arg(params, int), 10);
-        written += uart_puts(COM1, arg, -1);
-        vga_puts(arg, -1);
-      } break;
-      case 'u': {
-        const char *arg = utoa(buffer, va_arg(params, unsigned int), 10);
-        written += uart_puts(COM1, arg, -1);
-        vga_puts(arg, -1);
-      } break;
-      case 'x': {
-        const char *arg = utoa(buffer, va_arg(params, unsigned int), 16);
-        written += uart_puts(COM1, arg, -1);
-        vga_puts(arg, -1);
-      } break;
-      }
-
-      l = 0;
-    }
-
-    else
-      ++l;
-  }
-
-  if (l > 0) {
-    written += uart_puts(COM1, &format[s], l);
-    vga_puts(&format[s], l);
-  }
-
-  va_end(params);
-  vga_update_cursor();
-  return written;
+  va_list ap;
+  va_start(ap, format);
+  int c = vfprintf(stdout, format, ap);
+  va_end(ap);
+  return c;
 }
diff --git a/lib/stdio/vfprintf.c b/lib/stdio/vfprintf.c
new file mode 100644
index 0000000..d24e43e
--- /dev/null
+++ b/lib/stdio/vfprintf.c
@@ -0,0 +1,54 @@
+#include <stdio.h>
+#include <string.h>
+
+static char buffer[3 * sizeof(int) + 2];
+
+int
+vfprintf(FILE *restrict stream, const char *restrict format, va_list params)
+{
+  int written = 0;
+
+  int s = 0;
+  int l = 0;
+  for (int i = 0; format[i] != '\0'; ++i) {
+    if (format[i] == '%') {
+      written += stream->puts(stream, &format[s], l);
+      s = i + 2;
+      ++i;
+
+      switch (format[i]) {
+      case 's': {
+        const char *arg = va_arg(params, const char *);
+        written += stream->puts(stream, arg, -1);
+      } break;
+      case 'c': {
+        const int arg = va_arg(params, int);
+        stream->putc(stream, arg);
+        ++written;
+      } break;
+      case 'd': {
+        const char *arg = itoa(buffer, va_arg(params, int), 10);
+        written += stream->puts(stream, arg, -1);
+      } break;
+      case 'u': {
+        const char *arg = utoa(buffer, va_arg(params, unsigned int), 10);
+        written += stream->puts(stream, arg, -1);
+      } break;
+      case 'x': {
+        const char *arg = utoa(buffer, va_arg(params, unsigned int), 16);
+        written += stream->puts(stream, arg, -1);
+      } break;
+      }
+
+      l = 0;
+    }
+
+    else
+      ++l;
+  }
+
+  if (l > 0) { written += stream->puts(stream, &format[s], l); }
+
+  stream->flush(stream);
+  return written;
+}
diff --git a/lib/stdlib.h b/lib/stdlib.h
index 7f235f0..bd8474d 100644
--- a/lib/stdlib.h
+++ b/lib/stdlib.h
@@ -1,9 +1,11 @@
 #pragma once
 
+#include <stddef.h>
+
 /**
  * Allocate size bytes and return a pointer to the allocated memory
  */
-void *malloc(unsigned int size);
+void *malloc(size_t size);
 
 /**
  * Free the memory space pointed to by ptr
diff --git a/src/kernel.c b/src/kernel.c
index 2777f72..a315f3b 100644
--- a/src/kernel.c
+++ b/src/kernel.c
@@ -15,11 +15,16 @@
 #include <stdio.h>
 #include <sys/cpuid.h>
 
+FILE *stdin;
+FILE *stdout;
+FILE *stderr;
+
 void kmain() {
-  vga_init(vmm_map(0xb8000, 0xc03ff000));
-  if (uart_init(COM1) != 0) printf("UART self-test failed.\r\n");
+  stderr = uart_init(COM1);
+  stdout = vga_init(vmm_map(0xb8000, 0xc03ff000));
 
   printf("glitch [version " VERSION "] [" CC "]\n");
+  fprintf(stderr, "glitch [version " VERSION "] [" CC "]\n");
   {
     char vendor[13] = {'\0'};
     unsigned int eax;
@@ -27,6 +32,7 @@ void kmain() {
     struct CPUVersion v;
     __get_cpuid(1, (unsigned int *)&v, &eax, &eax, &eax);
     printf("CPU: %s family %u model %u stepping %u\n", vendor, family(v), model(v), v.stepping);
+    fprintf(stderr, "CPU: %s family %u model %u stepping %u\n", vendor, family(v), model(v), v.stepping);
   }
 
   pic_init();
@@ -46,6 +52,5 @@ void kmain() {
 
   // asm volatile("int $0x80");
 
-  while (1)
-    ;
+  while (1) {}
 }