Added posix code

conts/posix/fs0/src/path.c

@@ -0,0 +1,145 @@
+/*
+ * Path manipulation functions.
+ *
+ * Copyright (C) 2008 Bahadir Balban
+ */
+#include <l4/macros.h>
+#include <l4/lib/list.h>
+#include <l4/api/errno.h>
+#include <lib/pathstr.h>
+#include <lib/malloc.h>
+#include <path.h>
+#include <stdio.h>
+#include <fs.h>
+#include <task.h>
+#include <vfs.h>
+
+const char *pathdata_next_component(struct pathdata *pdata)
+{
+	struct pathcomp *p, *n;
+	const char *pathstr;
+
+	list_foreach_removable_struct(p, n, &pdata->list, list) {
+		list_remove(&p->list);
+		pathstr = p->str;
+		kfree(p);
+		return pathstr;
+	}
+	return "";
+}
+
+/* Check there's at least one element, unlink and return the last element */
+const char *pathdata_last_component(struct pathdata *pdata)
+{
+	struct pathcomp *p;
+	const char *pathstr;
+
+	if (!list_empty(&pdata->list)) {
+		p = link_to_struct(pdata->list.prev, struct pathcomp, list);
+		list_remove(&p->list);
+		pathstr = p->str;
+		kfree(p);
+		return pathstr;
+	}
+
+	return "";
+}
+
+/* Unlink and free all path components in pathdata, and then free pathdata */
+void pathdata_destroy(struct pathdata *p)
+{
+	struct pathcomp *c, *n;
+
+	list_foreach_removable_struct(c, n, &p->list, list) {
+		list_remove(&c->list);
+		kfree(c);
+	}
+	kfree(p);
+}
+
+void pathdata_print(struct pathdata *p)
+{
+	struct pathcomp *comp;
+
+	printf("Extracted path is:\n");
+	list_foreach_struct(comp, &p->list, list)
+		printf("%s\n", comp->str);
+}
+
+/* Extracts all path components from pathname into more presentable form */
+struct pathdata *pathdata_parse(const char *pathname,
+				char *pathbuf, struct tcb *task)
+{
+	struct pathdata *pdata = kzalloc(sizeof(*pdata));
+	struct pathcomp *comp;
+	char *str;
+
+	if (!pdata)
+		return PTR_ERR(-ENOMEM);
+
+	/* Initialise pathdata */
+	link_init(&pdata->list);
+	strcpy(pathbuf, pathname);
+
+	/* First component is root if there's a root */
+	if (pathname[0] == VFS_CHAR_SEP) {
+		if (!(comp = kzalloc(sizeof(*comp)))) {
+			kfree(pdata);
+			return PTR_ERR(-ENOMEM);
+		}
+		link_init(&comp->list);
+		comp->str = VFS_STR_ROOTDIR;
+		list_insert_tail(&comp->list, &pdata->list);
+
+		if (task)
+			/* Lookup start vnode is root vnode */
+			pdata->vstart = task->fs_data->rootdir;
+		else /* If no task, we use the root mountpoint pivot vnode */
+			pdata->vstart = vfs_root.pivot;
+
+	/* Otherwise start from current directory */
+	} else {
+		struct dentry *curdir;
+
+		if (!(comp = kzalloc(sizeof(*comp)))) {
+			kfree(pdata);
+			return PTR_ERR(-ENOMEM);
+		}
+		link_init(&comp->list);
+
+		/* Get current dentry for this task */
+		curdir = link_to_struct(task->fs_data->curdir->dentries.next,
+				    struct dentry, vref);
+
+		/* Use its name in path component */
+		comp->str = curdir->name;
+		list_insert_tail(&comp->list, &pdata->list);
+
+		/* Lookup start vnode is current dir vnode */
+		pdata->vstart = task->fs_data->curdir;
+	}
+
+	/* Add every other path component */
+	str = splitpath(&pathbuf, VFS_CHAR_SEP);
+	while(*str) {
+		/* Any curdir components in path are ignored. */
+		if (!strcmp(str, VFS_STR_CURDIR)) {
+			;
+		} else {
+			if (!(comp = kzalloc(sizeof(*comp)))) {
+				pathdata_destroy(pdata);
+				return PTR_ERR(-ENOMEM);
+			}
+			link_init(&comp->list);
+			comp->str = str;
+			list_insert_tail(&comp->list, &pdata->list);
+		}
+
+		/* Next component */
+		str = splitpath(&pathbuf, VFS_CHAR_SEP);
+	}
+	// pathdata_print(pdata);
+
+	return pdata;
+}
+