WebSVN – HelenOS – Diff – //trunk/uspace/srv/fs/tmpfs/tmpfs_ops.c

 #include "tmpfs.h"
 #include "../../vfs/vfs.h"
 #include <ipc/ipc.h>
 #include <async.h>
 #include <errno.h>
+#include <atomic.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
 #define PLB_GET_CHAR(i)     (tmpfs_reg.plb_ro[(i) % PLB_SIZE])
+unsigned tmpfs_next_index = 1;
+static void tmpfs_dentry_initialize(tmpfs_dentry_t *dentry)
+{
+    dentry->index = 0;
+    dentry->parent = NULL;
+    dentry->sibling = NULL;
+    dentry->child = NULL;
+    dentry->name = NULL;
+    dentry->type = TMPFS_NONE;
+    dentry->size = 0;
+    dentry->data = NULL;
+}
+/*
+ * For now, we don't distinguish between different dev_handles/instances. All
+ * requests resolve to the only instance, rooted in the following variable.
+ */
+static tmpfs_dentry_t *root;
+static bool tmpfs_init(void)
+{
+    root = (tmpfs_dentry_t *) malloc(sizeof(tmpfs_dentry_t));
+    if (!root) {
+        return false;
+    }
+    tmpfs_dentry_initialize(root);
+    root->index = tmpfs_next_index++;
+    root->name = "";
+    root->type = TMPFS_DIRECTORY;
+    /*
+     * This is only for debugging. Once we can create files and directories
+     * using VFS, we can get rid of this.
+     */
+    tmpfs_dentry_t *d;
+    d = (tmpfs_dentry_t *) malloc(sizeof(tmpfs_dentry_t));
+    if (!d) {
+        free(root);
+        root = NULL;
+        return false;
+    }
+    tmpfs_dentry_initialize(d);
+    d->index = tmpfs_next_index++;
+    root->child = d;
+    d->parent = root;
+    d->type = TMPFS_DIRECTORY;
+    d->name = "dir1";
+    d = (tmpfs_dentry_t *) malloc(sizeof(tmpfs_dentry_t));
+    if (!d) {
+        free(root->child);
+        free(root);
+        root = NULL;
+        return false;
+    }
+    tmpfs_dentry_initialize(d);
+    d->index = tmpfs_next_index++;
+    root->child->sibling = d;
+    d->parent = root;
+    d->type = TMPFS_DIRECTORY;
+    d->name = "dir2";
+    d = (tmpfs_dentry_t *) malloc(sizeof(tmpfs_dentry_t));
+    if (!d) {
+        free(root->child->sibling);
+        free(root->child);
+        free(root);
+        root = NULL;
+        return false;
+    }
+    tmpfs_dentry_initialize(d);
+    d->index = tmpfs_next_index++;
+    root->child->child = d;
+    d->parent = root->child;
+    d->type = TMPFS_FILE;
+    d->name = "file1";
+    d->data = "This is the contents of /dir1/file1.\n";
+    d->size = strlen(d->data);
+    d = (tmpfs_dentry_t *) malloc(sizeof(tmpfs_dentry_t));
+    if (!d) {
+        free(root->child->sibling);
+        free(root->child->child);
+        free(root->child);
+        free(root);
+        root = NULL;
+        return false;
+    }
+    tmpfs_dentry_initialize(d);
+    d->index = tmpfs_next_index++;
+    root->child->sibling->child = d;
+    d->parent = root->child->sibling;
+    d->type = TMPFS_FILE;
+    d->name = "file2";
+    d->data = "This is the contents of /dir2/file2.\n";
+    d->size = strlen(d->data);
+    return true;
+}
 /** Compare one component of path to a directory entry.
+ *
  * @param dentry    Directory entry to compare the path component with.
  * @param start     Index into PLB where the path component starts.
  * @param last      Index of the last character of the path in PLB.
+ *
  * @return      Zero on failure or delta such that (index + delta) %
- *          PLB_SIZE points to a new path component in PLB.
+ *          PLB_SIZE points to the first unprocessed character in
+ *          PLB which comprises the path.
  */
 static unsigned match_path_component(tmpfs_dentry_t *dentry, unsigned start,
     unsigned last)
+{
+    int i, j;
+    size_t namelen;
+    namelen = strlen(dentry->name);
+    if (last < start)
+        last += PLB_SIZE;
+    for (i = 0, j = start; i < namelen && j <= last; i++, j++) {
+        if (dentry->name[i] != PLB_GET_CHAR(j))
+            return 0;
+    }
+    if (i != namelen)
-    return 0;
+        return 0;
+    if (j < last && PLB_GET_CHAR(j) != '/')
+        return 0;
+    if (j == last)
+            return 0;
+    return (j - start);
+}
 void tmpfs_lookup(ipc_callid_t rid, ipc_call_t *request)
+{
-    int first = IPC_GET_ARG1(*request);
+    unsigned next = IPC_GET_ARG1(*request);
-    int second = IPC_GET_ARG2(*request);
+    unsigned last = IPC_GET_ARG2(*request);
     int dev_handle = IPC_GET_ARG3(*request);
+    if (last < next)
+        last += PLB_SIZE;
+    if (!root && !tmpfs_init()) {
+        ipc_answer_0(rid, ENOMEM);
+        return;
+    }
+    tmpfs_dentry_t *dtmp = root->child;
+    tmpfs_dentry_t *dcur = root;
+    bool hit = true;
+    if (PLB_GET_CHAR(next) == '/')
+        next++;     /* eat slash */
+    while (next <= last) {
+        unsigned delta;
+        hit = false;
+        do {
+            delta = match_path_component(dtmp, next, last);
+            if (!delta) {
+                dtmp = dtmp->sibling;
+            } else {
+                hit = true;
+                next += delta;
+                next++;     /* eat slash */
+                dcur = dtmp;
+                dtmp = dtmp->child;
+            }
+        } while (delta == 0 && dtmp);
+        if (!hit) {
+            ipc_answer_3(rid, ENOENT, tmpfs_reg.fs_handle,
+                dev_handle, dcur->index);
+            return;
+        }
+    }
+    ipc_answer_3(rid, EOK, tmpfs_reg.fs_handle, dev_handle, dcur->index);
+}
 /**
  * @}
  */

Subversion Repositories HelenOS

(root)//trunk/uspace/srv/fs/tmpfs/tmpfs_ops.c – Rev 2645 → 2655