+/*
+ * Functions for handling UObject package search paths.
+ * Copyright (C) 2009 Nick Bowler
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+
+#include <uobject/vfs.h>
+#include <ltdl.h>
+
+#include "avl.h"
+
+/* Check if a character is a directory separator. */
+#ifdef LT_DIRSEP_CHAR
+# define IS_DIRSEP(x) ((x) == '/' || (x) == LT_DIRSEP_CHAR)
+#else
+# define IS_DIRSEP(x) ((x) == '/')
+#endif
+
+struct local_pkg {
+ char *file, *name;
+};
+
+static struct avl_table *local_tree;
+static int initialized;
+
+static int localcmp(const void *_a, const void *_b, void *_data)
+{
+ const struct local_pkg *a = _a, *b = _b;
+ return strcasecmp(a->name, b->name);
+}
+
+static const char *pkgname_base(const char *file)
+{
+ const char *base = NULL;
+ int slash = 1;
+
+ for (size_t i = 0; file[i]; i++) {
+ if (IS_DIRSEP(file[i])) {
+ slash = 1;
+ } else if (slash == 1) {
+ base = file+i;
+ slash = 0;
+ }
+ }
+
+ return base;
+}
+
+static size_t pkgname_len(const char *base)
+{
+ size_t i;
+
+ for (i = 0; base[i]; i++) {
+ if (IS_DIRSEP(base[i]) || base[i] == '.')
+ break;
+ }
+
+ return i;
+}
+
+const char *u_pkg_vfs_add_local(const char *name, const char *file)
+{
+ size_t filelen = strlen(file)+1, namelen;
+ struct local_pkg *spec;
+
+ if (!name)
+ name = pkgname_base(file);
+ if (!name)
+ return NULL;
+ namelen = pkgname_len(name);
+
+ /* For simplicity, stuff everything in a single allocation. */
+ spec = malloc(sizeof *spec + filelen + namelen + 1);
+ if (!spec) {
+ return NULL;
+ }
+
+ spec->file = (char *)spec + sizeof *spec;
+ memcpy(spec->file, file, filelen);
+
+ spec->name = (char *)spec + sizeof *spec + filelen;
+ memcpy(spec->name, name, namelen);
+ spec->name[namelen] = 0;
+
+ if (avl_find(local_tree, spec)) {
+ fprintf(stderr, "%s: attempted to add duplicate local package.\n", __func__);
+ name = spec->name;
+ free(spec);
+ return name; /* "Success"-ish. */
+ }
+
+ if (avl_probe(local_tree, spec) == NULL) {
+ free(spec);
+ return NULL;
+ }
+
+ return spec->name;
+}
+
+void u_pkg_vfs_del_local(const char *name)
+{
+ struct local_pkg spec = { .name = (char *)name }, *item;
+
+ item = avl_find(local_tree, &spec);
+ free(item);
+}
+
+const char *u_pkg_vfs_lookup(const char *name)
+{
+ struct local_pkg spec = { .name = (char *)name }, *item;
+
+ if (!local_tree)
+ return NULL;
+
+ item = avl_find(local_tree, &spec);
+ if (!item)
+ return NULL;
+ return item->file;
+}
+
+int u_pkg_vfs_init(void)
+{
+ if (!initialized) {
+ local_tree = avl_create(localcmp, NULL, NULL);
+ if (!local_tree) {
+ fprintf(stderr, "%s: failed to create local module tree.\n", __func__);
+ return -1;
+ }
+ }
+
+ initialized++;
+ return 0;
+}
+
+static void local_destroy(void *item, void *data)
+{
+ free(item);
+}
+
+void u_pkg_vfs_exit(void)
+{
+ if (--initialized == 0)
+ avl_destroy(local_tree, local_destroy);
+}