Remove the notion of "sys*"

- This idea originates from very early in the project and was, at the
  time, a very easy way to categorise things.
- Now, it doesn't really make much sense - it is fairly arbitary, often
  occuring when there is a change in kernel, but not from builder-hex0
  to fiwix, and sysb is in reality completely unnecessary.
- In short, the sys* stuff is a bit of a mess that makes the project
  more difficult to understand.
- This puts everything down into one folder and has a manifest file that
  is used to generate the build scripts on the fly rather than using
  coded scripts.
- This is created in the "seed" stage.

stage0-posix -- (calls) --> seed -- (generates) --> main steps

Alongside this change there are a variety of other smaller fixups to the
general structure of the live-bootstrap rootfs.

- Creating a rootfs has become much simpler and is defined as code in
  go.sh. The new structure, for an about-to-be booted system, is

/
-- /steps (direct copy of steps/)
-- /distfiles (direct copy of distfiles/)
-- all files from seed/*
-- all files from seed/stage0-posix/*

- There is no longer such a thing as /usr/include/musl, this didn't
  really make any sense, as musl is the final libc used. Rather, to
  separate musl and mes, we have /usr/include/mes, which is much easier
  to work with.
- This also makes mes easier to blow away later.
- A few things that weren't properly in packages have been changed;
  checksum-transcriber, simple-patch, kexec-fiwix have all been given
  fully qualified package names.
- Highly breaking change, scripts now exist in their package directory
  but NOT WITH THE packagename.sh. Rather, they use pass1.sh, pass2.sh,
  etc. This avoids manual definition of passes.
  - Ditto with patches; default directory is patches, but then any patch
    series specific to a pass are named patches-passX.

steps/kexec-linux-1.0.0/files/kexec-linux.c

@@ -0,0 +1,87 @@
+/* SPDX-FileCopyrightText: 2023 Richard Masters <grick23@gmail.com> */
+/* SPDX-License-Identifier: MIT */
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <sys/reboot.h>
+#include <sys/stat.h>
+#include <time.h>
+
+int append_file(FILE *dst_file, char *src_file_name);
+
+int main(int argc, char **argv) {
+	char *ramdrive_file_name, *kernel_file_name, *initramfs_file_name;
+	FILE *ramdrive_file;
+	struct stat stats;
+	uint32_t size;
+
+	if (argc < 3) {
+		puts("Usage: fiwix-kexec-linux <ram-drive-name> <kernel-file-name> <initramfs-file-name>");
+		exit(1);
+	}
+
+	ramdrive_file_name = argv[1];
+	kernel_file_name = argv[2];
+	initramfs_file_name = argv[3];
+
+	ramdrive_file = fopen(ramdrive_file_name, "wb");
+
+	/* Move past where lengths go */
+	int length_offset = 2 * sizeof(uint32_t);
+	fseek(ramdrive_file, length_offset, SEEK_SET);
+	uint32_t last_pos = ftell(ramdrive_file);
+
+	/* Write the kernel and initramfs */
+	if (append_file(ramdrive_file, kernel_file_name)) {
+		fprintf(stderr, "Cannot append kernel '%s'\n", kernel_file_name);
+		exit(1);
+	}
+
+	uint32_t kernel_size = ftell(ramdrive_file) - last_pos;
+	last_pos = ftell(ramdrive_file);
+
+	if (append_file(ramdrive_file, initramfs_file_name)) {
+		fprintf(stderr, "Cannot append initramfs '%s'\n", initramfs_file_name);
+		exit(1);
+	}
+
+	uint32_t initramfs_size = ftell(ramdrive_file) - last_pos;
+
+	/* Now write the lengths */
+	fseek(ramdrive_file, 0, SEEK_SET);
+	fwrite(&kernel_size, sizeof(kernel_size), 1, ramdrive_file);
+	fwrite(&initramfs_size, sizeof(initramfs_size), 1, ramdrive_file);
+
+	fclose(ramdrive_file);
+
+	/* Flush ram drive writes to device */
+	sync();
+
+	/* Perform syscall reboot to initiate kexec */
+	reboot(RB_HALT_SYSTEM);
+}
+
+int append_file(FILE *dst_file, char *src_file_name) {
+	FILE *src_file;
+	char buff[BUFSIZ];
+	size_t n;
+
+	if (*src_file_name == '!') {
+		src_file_name++;
+		src_file = popen(src_file_name, "r");
+	} else {
+		src_file = fopen(src_file_name, "rb");
+	}
+ 
+	if (src_file) {
+		while ((n = fread(buff, 1, BUFSIZ, src_file)) != 0) {
+			fwrite(buff, 1, n, dst_file);
+		}
+		fclose(src_file);
+		return 0;
+	} else {
+		printf("Cannot open file '%s'\n", src_file_name);
+		return 1;
+	}
+}

steps/kexec-linux-1.0.0/mk/main.mk

@@ -0,0 +1,4 @@
+# SPDX-FileCopyrightText: 2023 Richard Masters <grick23@gmail.com>
+# SPDX-License-Identifier: MIT
+kexec-linux: kexec-linux.c
+	gcc -static -m32 -march=i386 -o $@ $^

steps/kexec-linux-1.0.0/pass1.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+# SPDX-FileCopyrightText: 2023 Richard Masters <grick23@gmail.com>
+# SPDX-License-Identifier: MIT
+src_get() {
+    :
+}
+
+src_unpack() {
+    dirname=kexec-linux-1.0.0
+    mkdir ${dirname}
+}
+
+src_install() {
+    install -D "kexec-linux" "${DESTDIR}${PREFIX}/bin/kexec-linux"
+}