#include <stdlib.h>

 #include <stdint.h>

 #include <stdio.h>

 #include <sys/stat.h>

 #include <dirent.h>

 #include <unistd.h>

 #include <fcntl.h>

 #include "razor.h"

 #include "razor-internal.h"

 static const char system_repo_filename[] = "system.repo";

 static const char next_repo_filename[] = "system-next.repo";

 static const char razor_root_path[] = "/var/lib/razor";

 struct razor_root {

 	struct razor_set *system;

 	struct razor_set *next;

 	int fd;

 	char path[PATH_MAX];

 	char new_path[PATH_MAX];

 };

 int

 razor_root_create(const char *root)

 {

 	struct stat buf;

 	struct razor_set *set;

 	char path[PATH_MAX];

 	if (stat(root, &buf) < 0) {

 		if (mkdir(root, 0777) < 0) {

 			fprintf(stderr,

 				"could not create install root \"%s\"\n",

 				root);

 			return -1;

 		}

 		fprintf(stderr, "created install root \"%s\"\n", root);

 	} else if (!S_ISDIR(buf.st_mode)) {

 		fprintf(stderr,

 			"install root \"%s\" exists, but is not a directory\n",

 			root);

 		return -1;

 	}

 	snprintf(path, sizeof path, "%s/%s",

 		 razor_root_path, system_repo_filename);

 	if (razor_create_dir(root, path) < 0) {

 		fprintf(stderr, "could not create %s%s\n",

 			root, razor_root_path);

 		return -1;

 	}

 	set = razor_set_create();

 	snprintf(path, sizeof path, "%s%s/%s",

 		 root, razor_root_path, system_repo_filename);

 	if (stat(path, &buf) == 0) {

 		fprintf(stderr,

 			"a razor install root is already initialized\n");

 		return -1;

 	}

 	if (razor_set_write(set, path) < 0) {

 		fprintf(stderr, "could not write initial package set\n");

 		return -1;

 	}

 	razor_set_destroy(set);

 	return 0;

 }

 struct razor_root *

 razor_root_open(const char *root, int flags)

 {

 	struct razor_root *image;

 	image = malloc(sizeof *image);

 	if (image == NULL)

 		return NULL;

 	/* Create the new next repo file up front to ensure exclusive

 	 * access. */

 	snprintf(image->new_path, sizeof image->new_path,

 		 "%s%s/%s", root, root, next_repo_filename);

 	image->fd = open(image->new_path,

 			 O_CREAT | O_WRONLY | O_TRUNC | O_EXCL, 0666);

 	if (image->fd < 0) {

 		fprintf(stderr, "failed to get lock file, "

 			"maybe previous operation crashed?\n");

 		/* FIXME: Use fcntl advisory locking on the system

 		 * package set file to figure out whether previous

 		 * operation crashed or is still in progress. */

 		free(image);

 		return NULL;

 	}

 	snprintf(image->path, sizeof image->path,

 		 "%s%s/%s", root, razor_root_path, system_repo_filename);

 	image->system = razor_set_open(image->path);

 	if (image->system == NULL) {

 		unlink(image->new_path);

 		close(image->fd);

 		free(image);

 		return NULL;

 	}

 	return image;

 }

 struct razor_set *

 razor_root_open_read_only(const char *root)

 {

 	char path[PATH_MAX];

 	snprintf(path, sizeof path, "%s%s/%s",

 		 root, razor_root_path, system_repo_filename);

 	return razor_set_open(path);

 }

 struct razor_transaction *

 razor_root_create_transaction(struct razor_root *image,

 			      struct razor_set *upstream)

 {

 	/* FIXME: This should take a number of upstream repos. */

 	return razor_transaction_create(image->system, upstream);

 }

 int

 razor_root_close(struct razor_root *image)

 {

 	unlink(image->new_path);

 	close(image->fd);

 	free(image);

 	return 0;

 }

 void

 razor_root_update(struct razor_root *root, struct razor_set *next)

 {

 	razor_set_write_to_fd(next, root->fd);

 	root->next = next;

 	/* Sync the new repo file so the new package set is on disk

 	 * before we start upgrading. */

 	fsync(root->fd);

 	printf("wrote %s\n", root->new_path);

 }

 int

 razor_root_commit(struct razor_root *image)

 {

 	/* Make it so. */

 	rename(image->new_path, image->path);

 	printf("renamed %s to %s\n", image->new_path, image->path);

 	close(image->fd);

 	free(image);

 	return 0;

 }

 void

 razor_root_diff(struct razor_root *root,

 		razor_package_callback_t callback, void *data)

 {

 	return razor_set_diff(root->system, root->next, callback, data);

 }