Initial ramdisk support

- Create initrd library to support definitions and loading
- Allow tools compiled for the host machine to be built by wscript
- Create makerd tool to build initrd from manifest
- Move screenfont to initrd, so don't load framebuffer initially

src/kernel/device_manager.cpp

@@ -41,19 +41,10 @@ struct acpi2_rsdp
 	uint8_t reserved[3];
 } __attribute__ ((packed));
 
-uint8_t
-acpi_checksum(const void *p, size_t len, size_t off = 0)
-{
-	uint8_t sum = 0;
-	const uint8_t *c = reinterpret_cast<const uint8_t *>(p);
-	for (int i = off; i < len; ++i) sum += c[i];
-	return sum;
-}
-
 bool
 acpi_table_header::validate(uint32_t expected_type) const
 {
-	if (acpi_checksum(this, length) != 0) return false;
+	if (kutil::checksum(this, length) != 0) return false;
 	return !expected_type || (expected_type == type);
 }
 
@@ -86,7 +77,7 @@ device_manager::device_manager(const void *root_table) :
 		kassert(acpi1->signature[i] == expected_signature[i],
 				"ACPI RSDP table signature mismatch");
 
-	uint8_t sum = acpi_checksum(acpi1, sizeof(acpi1_rsdp), 0);
+	uint8_t sum = kutil::checksum(acpi1, sizeof(acpi1_rsdp), 0);
 	kassert(sum == 0, "ACPI 1.0 RSDP checksum mismatch.");
 
 	kassert(acpi1->revision > 1, "ACPI 1.0 not supported.");
@@ -94,7 +85,7 @@ device_manager::device_manager(const void *root_table) :
 	const acpi2_rsdp *acpi2 =
 		reinterpret_cast<const acpi2_rsdp *>(acpi1);
 
-	sum = acpi_checksum(acpi2, sizeof(acpi2_rsdp), sizeof(acpi1_rsdp));
+	sum = kutil::checksum(acpi2, sizeof(acpi2_rsdp), sizeof(acpi1_rsdp));
 	kassert(sum == 0, "ACPI 2.0 RSDP checksum mismatch.");
 
 	load_xsdt(reinterpret_cast<const acpi_xsdt *>(acpi2->xsdt_address));

src/kernel/main.cpp

@@ -1,13 +1,13 @@
 #include <stddef.h>
 #include <stdint.h>
 
+#include "initrd/initrd.h"
 #include "kutil/assert.h"
 #include "kutil/memory.h"
 #include "block_device.h"
 #include "console.h"
 #include "cpu.h"
 #include "device_manager.h"
-#include "font.h"
 #include "gdt.h"
 #include "interrupts.h"
 #include "io.h"
@@ -29,23 +29,11 @@ extern "C" {
 extern void __kernel_assert(const char *, unsigned, const char *);
 
 void
-init_console(const popcorn_data *header)
+init_console()
 {
 	serial_port *com1 = new (&g_com1) serial_port(COM1);
 	console *cons = new (&g_console) console(com1);
 
-	if (header->frame_buffer) {
-		screen *s = new screen(
-				header->frame_buffer,
-				header->hres,
-				header->vres,
-				header->rmask,
-				header->gmask,
-				header->bmask);
-		font *f = new font(header->font);
-		cons->init_screen(s, f);
-	}
-
 	cons->set_color(0x21, 0x00);
 	cons->puts("Popcorn OS ");
 	cons->set_color(0x08, 0x00);
@@ -83,16 +71,20 @@ kernel_main(popcorn_data *header)
 			&header->frame_buffer,
 			header->frame_buffer_length);
 
-	init_console(header);
+	init_console();
 
 	log::debug(logs::boot, " Popcorn header is at: %016lx", header);
 	log::debug(logs::boot, "    Framebuffer is at: %016lx", header->frame_buffer);
-	log::debug(logs::boot, "      Font data is at: %016lx", header->font);
 	log::debug(logs::boot, "    Kernel data is at: %016lx", header->data);
 	log::debug(logs::boot, "     Memory map is at: %016lx", header->memory_map);
 	log::debug(logs::boot, "ACPI root table is at: %016lx", header->acpi_table);
 	log::debug(logs::boot, "Runtime service is at: %016lx", header->runtime);
 
+	initrd::disk ird(header->initrd);
+	log::info(logs::boot, "initrd loaded with %d files.", ird.files().count());
+	for (auto &f : ird.files())
+		log::info(logs::boot, "  %s (%d bytes).", f.name(), f.size());
+
 	/*
 	pager->dump_pml4(nullptr, 0);
 	pager->dump_blocks(true);

src/kernel/wscript

@@ -15,7 +15,7 @@ def build(bld):
         name = 'kernel',
         includes = '.',
         target = bld.env.KERNEL_FILENAME,
-        use = 'kutil',
+        use = ['kutil', 'initrd'],
         linkflags = "-T {}".format(lds),
     )