diff -r 000000000000 -r 7f5d32472bef razor-root.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/razor-root.c	Mon Jun 09 16:14:05 2008 -0400
@@ -0,0 +1,157 @@
+#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(root, &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_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);
+}