rosetta/sys/bootstrap/main.c

#define MSG_IMPLEMENTATION
#define MSG_NO_MALLOC

#include "tar.h"

#include <fs/allocator.h>
#include <fs/context.h>
#include <heap/heap.h>
#include <launch.h>
#include <mango/log.h>
#include <mango/msg.h>
#include <mango/task.h>
#include <mango/types.h>
#include <rosetta/bootstrap.h>
#include <rosetta/fs.h>
#include <stdint.h>
#include <stdio.h>

#define INIT_PATH "/usr/bin/test"

static enum launch_status resolve_dependency(
	struct launch_ctx *ctx,
	const char *name,
	kern_handle_t *out,
	void *arg)
{
	char s[128];
	while (*name == '/') {
		name++;
	}

	snprintf(s, sizeof s, "searching for library %s", name);
	kern_log(s);

	struct tar *fs = arg;
	struct tar_file file = {0};
	if (tar_open(fs, name, &file) != 0) {
		snprintf(s, sizeof s, "cannot find library %s", name);
		kern_log(s);
		return LAUNCH_ERR_CANNOT_RESOLVE_DEPENDENCY;
	}

	kern_handle_t image = KERN_HANDLE_INVALID;
	int err = tar_file_create_vm_object(&file, &image);
	if (err != 0) {
		snprintf(s, sizeof s, "cannot load library %s", name);
		kern_log(s);
		return -1;
	}

	*out = image;
	return LAUNCH_OK;
}

static kern_status_t open(
	xpc_context_t *ctx,
	const xpc_endpoint_t *sender,
	const char *path,
	int flags,
	int *out_err,
	void *arg)
{
	kern_logf(
		"received msg: [%u.%x] open(%s, %d)",
		sender->e_task,
		sender->e_port,
		path,
		flags);
	*out_err = 13;
	return KERN_OK;
}

static void *_fs_alloc(struct fs_allocator *alloc, size_t count)
{
	return heap_alloc(alloc->fs_arg, count);
}

static void *_fs_calloc(struct fs_allocator *alloc, size_t count, size_t sz)
{
	return heap_calloc(alloc->fs_arg, count, sz);
}

static void *_fs_realloc(struct fs_allocator *alloc, void *p, size_t count)
{
	return heap_realloc(alloc->fs_arg, p, count);
}

static void _fs_free(struct fs_allocator *alloc, void *p)
{
	heap_free(alloc->fs_arg, p);
}

int main(
	int argc,
	const char **argv,
	kern_handle_t task,
	kern_handle_t address_space,
	uintptr_t bsp_base)
{
	struct tar bsp = {0};
	if (tar_init(&bsp, bsp_base) != 0) {
		kern_log("cannot access bsp");
		return -1;
	}

	struct tar_file init = {0};
	if (tar_open(&bsp, INIT_PATH, &init) != 0) {
		kern_log("cannot find init program " INIT_PATH);
		return -1;
	}

	kern_trace("loading " INIT_PATH);

	kern_handle_t image = KERN_HANDLE_INVALID;
	int err = tar_file_create_vm_object(&init, &image);
	if (err != 0) {
		kern_log("cannot load executable " INIT_PATH);
		return -1;
	}

	kern_trace("loaded executable vm-object " INIT_PATH);

	kern_tracef("task=%x, region=%x", task, address_space);

	struct launch_ctx launch;
	struct launch_result result;
	const char *init_argv[] = {
		"init",
		"arg1",
		"arg2",
		"arg3",
	};
	const char *init_env[] = {
		"TESTVAR=testvalue",
	};
	struct rosetta_bootstrap_channel init_channels[] = {
		{
			.c_type = RSBS_CHANNEL_SYSTEM,
			.c_tid = 0,
			.c_cid = 0,
		},
	};

	struct launch_parameters params = {
		.p_executable = image,
		.p_parent_task = task,
		.p_task_name = "init",
		.p_local_address_space = address_space,
		.p_resolver_arg = &bsp,
		.p_argc = sizeof init_argv / sizeof init_argv[0],
		.p_argv = init_argv,
		.p_envc = sizeof init_env / sizeof init_env[0],
		.p_envp = init_env,
		.p_channel_count
		= sizeof init_channels / sizeof init_channels[0],
		.p_channels = init_channels,
	};

	kern_handle_t channel;
	channel_create(0, &channel);

	launch_ctx_init(&launch);
	launch.ctx_resolve_library = resolve_dependency;

	enum launch_status status
		= launch_ctx_execute(&launch, &params, LAUNCH_F_NONE, &result);
	if (status != KERN_OK) {
		kern_logf("failed to start init: %d", status);
		return -1;
	}

	heap_t heap = HEAP_INIT;

	struct fs_allocator fs_allocator = {
		.fs_alloc = _fs_alloc,
		.fs_calloc = _fs_calloc,
		.fs_realloc = _fs_realloc,
		.fs_free = _fs_free,
		.fs_arg = &heap,
	};

	struct fs_context *fs = fs_context_create(&fs_allocator);
	if (!fs) {
		kern_logf("cannot initialise fs");
		return -1;
	}

	enum fs_status fs_status = fs_context_mount_filesystem(
		fs,
		tar_mount,
		(void *)bsp_base,
		0);
	if (fs_status != FS_SUCCESS) {
		kern_logf("cannot mount filesustem (%d)", fs_status);
		return -1;
	}

	while (1) {
		xpc_msg_t msg;
		kern_status_t status = xpc_msg_recv(channel, &msg);
		if (status != KERN_OK) {
			kern_logf("message recv error %d", status);
			continue;
		}

		switch (msg.msg_header.hdr_interface) {
		case INTERFACE_FS:
			status = fs_context_dispatch_msg(fs, &msg);
			break;
		default:
			kern_logf(
				"unknown message protocol %u",
				msg.msg_header.hdr_interface);
			xpc_msg_reply_error(&msg, KERN_UNSUPPORTED);
			break;
		}

		if (status != KERN_OK) {
			kern_logf("message reply error %d", status);
			continue;
		}
	}

	return 0;
}