src: filesystem: add core FAT16 functionality

Makefile

@@ -1,4 +1,4 @@
-FILES = ./build/kernel.asm.o ./build/kernel.o ./build/idt/idt.asm.o ./build/idt/idt.o ./build/memory/memory.o ./build/io/io.asm.o ./build/memory/heap/heap.o ./build/memory/heap/kheap.o ./build/memory/pmap/pmap.o ./build/memory/pmap/pmap.asm.o ./build/disk/disk.o ./build/filesystem/pathparser.o ./build/string/string.o ./build/disk/disk_stream.o ./build/filesystem/file.o
+FILES = ./build/kernel.asm.o ./build/kernel.o ./build/idt/idt.asm.o ./build/idt/idt.o ./build/memory/memory.o ./build/io/io.asm.o ./build/memory/heap/heap.o ./build/memory/heap/kheap.o ./build/memory/pmap/pmap.o ./build/memory/pmap/pmap.asm.o ./build/disk/disk.o ./build/filesystem/pathparser.o ./build/string/string.o ./build/disk/disk_stream.o ./build/filesystem/file.o ./build/filesystem/fat/fat16.o
 
 INCLUDES = -I./src
 
@@ -58,6 +58,9 @@ all: ./bin/boot.bin ./bin/kernel.bin
 ./build/filesystem/file.o: ./src/filesystem/file.c
 	i686-elf-gcc $(INCLUDES) -I./src/filesystem $(FLAGS) -std=gnu99 -c ./src/filesystem/file.c -o ./build/filesystem/file.o
 
+./build/filesystem/fat/fat16.o: ./src/filesystem/fat/fat16.c
+	i686-elf-gcc $(INCLUDES) -I./src/filesystem $(FLAGS) -std=gnu99 -c ./src/filesystem/fat/fat16.c -o ./build/filesystem/fat/fat16.o
+
 ./build/filesystem/pathparser.o: ./src/filesystem/pathparser.c
 	i686-elf-gcc $(INCLUDES) -I./src/filesystem $(FLAGS) -std=gnu99 -c ./src/filesystem/pathparser.c -o ./build/filesystem/pathparser.o
 

src/filesystem/fat/fat16.c

@@ -0,0 +1,28 @@
+#include "fat16.h"
+#include "status.h"
+#include "string/string.h"
+
+int fat16_resolve(struct disk *disk);
+void *fat16_open(struct disk *disk, struct path_part *path, FILE_MODE mode);
+
+struct filesystem fat16_fs = {
+    .resolve = fat16_resolve,
+    .open = fat16_open
+};
+
+struct filesystem *
+fat16_init() {
+    strcpy(fat16_fs.name, "FAT16");
+    return &fat16_fs;
+}
+
+int 
+fat16_resolve(struct disk *disk) {
+    return 0;
+}
+
+void *
+fat16_open(struct disk *disk, struct path_part *path, FILE_MODE mode)
+{
+    return 0;
+}

src/filesystem/fat/fat16.h

@@ -0,0 +1,8 @@
+#ifndef FAT16_H
+#define FAT16_H
+
+#include "file.h"
+
+struct filesystem *fat16_init();
+
+#endif // FAT16_H

src/filesystem/file.c

@@ -4,6 +4,7 @@
 #include "memory/heap/kheap.h"
 #include "status.h"
 #include "kernel.h"
+#include "fat/fat16.h"
 
 struct filesystem *filesystems[MAX_FILESYSTEMS];
 
@@ -40,7 +41,7 @@ fs_insert_filesystem(struct filesystem *filesystem)
 static void
 fs_static_load()
 {
-    //fs_insert_filesystem(fat16_init());
+    fs_insert_filesystem(fat16_init());
 }
 
 void

src/kernel.c

@@ -7,6 +7,7 @@
 #include "filesystem/pathparser.h"
 #include "string/string.h"
 #include "disk/disk_stream.h"
+#include "filesystem/file.h"
 
 uint16_t *video_mem = 0;
 
@@ -100,12 +101,18 @@ kernel_main()
     print(kernel_logo5);
     print(kernel_logo6);
 
-    print("\nWelcome to silentOS v0.0.1\n");
+    print("\nWelcome to silentOS v0.0.2\n");
 
+    // initialize the heap
     kheap_init();
 
+    // initialize fat16 filesystem
+    fs_init();
+
+    // search for and initialize available disks
     disk_search_and_init();
 
+    // initialize the interrupt descriptor table
     idt_init();
 
     kernel_chunk = pmap_new_chunk(PMAP_IS_WRITEABLE | PMAP_IS_PRESENT | PMAP_ACCESS_FROM_ALL);
@@ -117,11 +124,7 @@ kernel_main()
     enable_interrupts();
 
 
-    struct disk_stream *stream = diskstream_new(0);
 
-    diskstream_seek(stream, 0x201);
-    char c = 0;
-    diskstream_read(stream, &c, 1);
     while (1)
     {
 

src/string/string.c

@@ -23,6 +23,19 @@ strnlen(const char *ptr, int max_length)
     return i;
 }
 
+char *strcpy(char *dest, const char *src) {
+    char *tmp = dest;
+    while (*src != 0) {
+        *dest = *src;
+        src += 1;
+        dest += 1;
+    }
+
+    *dest = 0x00;
+
+    return tmp;
+}
+
 int
 is_digit(char c)
 {

src/string/string.h

@@ -3,6 +3,7 @@
 
 int strlen(const char *ptr);
 int strnlen(const char *ptr, int max_length);
+char *strcpy(char *dest, const char *src);
 int is_digit(char c);
 int ascii_char_to_digit(char c);