Files partially implemented

Niski.code-workspace

@@ -40,7 +40,10 @@
 			"thread_local.h": "c",
 			"stdint.h": "c",
 			"signal.h": "c",
-			"threads.h": "c"
+			"threads.h": "c",
+			"stdio.h": "c",
+			"syscall_codes.h": "c",
+			"io.h": "c"
 		}
 	}
 }

Software/h/common/io.h

@@ -0,0 +1,12 @@
+#pragma once
+
+#include <stddef.h>
+
+enum __file {
+	__FILE_LCD,
+	__FILE_KEYBOARD,
+	__FILE_UART
+};
+
+size_t __io_write(enum __file file, const char* buffer, size_t size);
+size_t __io_read(enum __file file, char* buffer, size_t size);

Software/h/common/syscall_codes.h

@@ -29,4 +29,7 @@
 #define __SYSCALL_THREAD_STORAGE_SET 0x44
 
 #define __SYSCALL_SIGNAL_SET_HANDLER 0x51
-#define __SYSCALL_SIGNAL_RAISE 0x52
+#define __SYSCALL_SIGNAL_RAISE 0x52
+
+#define __SYSCALL_FILE_WRITE 0x61
+#define __SYSCALL_FILE_READ 0x62

Software/h/common/syscalls.h

@@ -4,6 +4,7 @@
 #include <stdbool.h>
 #include "common/threads.h"
 #include "common/signals.h"
+#include "common/io.h"
 
 void* __memory_allocate(size_t size);
 void __memory_free(void* ptr);
@@ -33,4 +34,7 @@ void* __thread_storage_get(struct __thread_storage* ts);
 enum __thread_status __thread_storage_set(struct __thread_storage* ts, void* data);
 
 void (*__signal_set_handler(enum __signal sig, void (*handler)(enum __signal)))(enum __signal);
-void __signal_raise(enum __signal sig);
+void __signal_raise(enum __signal sig);
+
+size_t __file_write(enum __file file, const char* buffer, size_t size);
+size_t __file_read(enum __file file, char* buffer, size_t size);

Software/h/kernel/io.h

@@ -0,0 +1,12 @@
+#pragma once
+
+#include <stddef.h>
+#include "common/io.h"
+
+struct kfile {
+	size_t (*write)(struct kfile* file, const char* buffer, size_t size);
+	size_t (*read)(struct kfile* file, char* buffer, size_t size);
+};
+
+size_t kfile_write(enum __file id, const char* buffer, size_t size);
+size_t kfile_read(enum __file id, char* buffer, size_t size);

Software/h/stdio.h

@@ -1,6 +1,49 @@
 #pragma once
 
+#include "common/io.h"
+#include "common/syscalls.h"
+
 #define EOF (-1)
 
-int putchar(int ch);
-int puts(const char* str);
+typedef struct FILE FILE;
+
+#define stdin  ((FILE*)__FILE_KEYBOARD)
+#define stdout ((FILE*)__FILE_LCD)
+#define stderr ((FILE*)__FILE_LCD)
+
+static inline int fputs(const char* str, FILE* restrict stream) {
+	size_t len = 0;
+	while (str[len] != '\0') len++;
+
+	size_t chars = __file_write((enum __file)stream, str, len);
+	if (chars != len) {
+		// TODO: set ferror
+		return EOF;
+	}
+
+	return chars;
+}
+
+static inline int fputc(int ch, FILE* stream) {
+	char c = ch;
+	size_t res = __file_write((enum __file)stream, &c, 1);
+	if (res != 1)
+		return EOF;
+
+	return ch;
+}
+
+#define putc(ch, stream) fputc(ch, stream)
+
+static inline int puts(const char* str) {
+	int res = fputs(str, stdout);
+	if (res == EOF)
+		return EOF;
+
+	if (fputc('\n', stdout) == EOF)
+		return EOF;
+
+	return res + 1;
+}
+
+static inline int putchar(int ch) { return fputc(ch, stdout); }

Software/src/common/syscalls.S

@@ -4,6 +4,7 @@
 .global __condition_create, __condition_wait, __condition_signal, __con_signal_all, __condition_destroy
 .global __thread_storage_create, __thread_storage_destroy, __thread_storage_get, __thread_storage_set
 .global __signal_set_handler, __signal_raise
+.global __file_write, __file_read
 
 #include "common/syscall_codes.h"
 
@@ -126,4 +127,14 @@ __signal_set_handler:
 __signal_raise:
 	li a5, __SYSCALL_SIGNAL_RAISE
 	ecall
+	ret
+
+__file_write:
+	li a5, __SYSCALL_FILE_WRITE
+	ecall
+	ret
+
+__file_read:
+	li a5, __SYSCALL_FILE_READ
+	ecall
 	ret

Software/src/kernel/exceptions/syscalls.c

@@ -5,6 +5,7 @@
 #include "kernel/sync/thread_local.h"
 #include "kernel/sync/scheduler.h"
 #include "kernel/signals.h"
+#include "kernel/io.h"
 #include "common/syscall_codes.h"
 
 #define GET_PARAM(index, type) (type)(kthread_current->context.regs[REG_A ## index])
@@ -310,6 +311,24 @@ static void syscall_sig_raise() {
 	SET_RET_VALUE(0);
 }
 
+static void syscall_file_write() {
+	enum __file file = GET_PARAM(0, enum __file);
+	const char* buffer = GET_PARAM(1, const char*);
+	size_t size = GET_PARAM(2, size_t);
+
+	size_t written = kfile_write(file, buffer, size);
+	SET_RET_VALUE(written);
+}
+
+static void syscall_file_read() {
+	enum __file file = GET_PARAM(0, enum __file);
+	char* buffer = GET_PARAM(1, char*);
+	size_t size = GET_PARAM(2, size_t);
+
+	size_t read = kfile_read(file, buffer, size);
+	SET_RET_VALUE(read);
+}
+
 static void (*syscalls[])() = {
 	[__SYSCALL_MEMORY_ALLOCATE] = syscall_mem_alloc,
 	[__SYSCALL_MEMORY_FREE] = syscall_mem_free,
@@ -341,6 +360,9 @@ static void (*syscalls[])() = {
 
 	[__SYSCALL_SIGNAL_SET_HANDLER] = syscall_sig_set_handler,
 	[__SYSCALL_SIGNAL_RAISE] = syscall_sig_raise,
+
+	[__SYSCALL_FILE_WRITE] = syscall_file_write,
+	[__SYSCALL_FILE_READ] = syscall_file_read,
 };
 
 void handle_syscall() {

Software/src/kernel/io/io.c

@@ -0,0 +1,17 @@
+#include "kernel/io.h"
+
+extern struct kfile klcd;
+
+struct kfile* files[] = {
+	[__FILE_LCD] = &klcd
+};
+
+size_t kfile_write(enum __file id, const char* buffer, size_t size) {
+	struct kfile* file = files[id];
+	return file->write(file, buffer, size);
+}
+
+size_t kfile_read(enum __file id, char* buffer, size_t size) {
+	struct kfile* file = files[id];
+	return file->read(file, buffer, size);
+}

Software/src/kernel/io/lcd.c

@@ -0,0 +1,35 @@
+#include "kernel/io.h"
+#include "devices/lcd.h"
+
+struct klcd {
+	char buffer[16][2];
+	int cursor_y, cursor_x;
+};
+
+size_t klcd_write(struct kfile* file, const char* buffer, size_t size) {
+	struct klcd* lcd = (struct klcd*)file;
+
+	for (size_t i = 0; i < size; i++) {
+		char ch = buffer[i];
+
+		// TODO: Fix this
+		switch (ch) {
+		case '\n':
+			lcd_move_cursor(1, 0);
+			break;
+		case '\r':
+			lcd_move_cursor(0, 0);
+			break;
+		default:
+			lcd_write_ch(ch);
+			break;
+		}
+	}
+
+	return size;
+}
+
+struct kfile klcd = {
+	.write = klcd_write,
+	.read = NULL
+};