Orion
Barry Importing existing Orion kernel d41a53c (3 years, 2 months ago)
diff --git a/vfs/tmpfs/file.c b/vfs/tmpfs/file.c
new file mode 100644
index 0000000..252c88f
--- /dev/null
+++ b/vfs/tmpfs/file.c
@@ -0,0 +1,126 @@
+/*
+ * This file controls access to TmpFS Files. It contains the functions called
+ * by the VFS for any operation on a File struct belonging to TmpFS.
+ */
+
+#include <stddef.h>
+#include <string.h>
+#include <errno.h>
+#include "fs.h"
+#include "../vfs.h"
+#include "../cache.h"
+#include "../../mem/paging.h"
+#include "../../mem/frame.h"
+
+size_t tmpfs_read(File *file, char *buf, size_t size, off_t offset);
+size_t tmpfs_write(File *file, char *buf, size_t size, off_t offset);
+int tmpfs_readdir(File *file, DirEnt *dent, off_t index);
+int tmpfs_open(File *file);
+
+FileOps tmpfsFileOps = {
+ .read = tmpfs_read,
+ .write = tmpfs_write,
+ .readdir = tmpfs_readdir,
+ .open = tmpfs_open,
+};
+
+/* Read a file */
+size_t
+tmpfs_read(File *file, char *buf, size_t size, off_t offset)
+{
+ if (offset > file->inode->size)
+ return 0;
+ if (size + offset > file->inode->size)
+ size = file->inode->size - offset;
+
+ uint16_t min;
+ size_t count = 0;
+ Page *page;
+ page_t oldPage;
+ while (size) {
+ min = (size > 0x1000) ? 0x1000 : size;
+ page = page_find(file->inode, offset);
+ if (!page)
+ break;
+ acquire(&quickPageLock);
+ oldPage = quick_page(page->frame);
+ memcpy(buf + count, QUICK_PAGE, min);
+ quick_page(oldPage);
+ release(&quickPageLock);
+ size -= min;
+ count += min;
+ }
+ return count;
+}
+
+/* Write a file */
+size_t
+tmpfs_write(File *file, char *buf, size_t size, off_t offset)
+{
+ if (size + offset > file->inode->size)
+ file->inode->size = size + offset;
+
+ uint16_t min;
+ size_t count = 0;
+ Page *page;
+ page_t oldPage;
+ while (size) {
+ min = (size > 0x1000) ? 0x1000 : size;
+ page = page_find(file->inode, offset);
+ if (!page)
+ page = page_create(file->inode, alloc_frames(1),
+ offset);
+ acquire(&quickPageLock);
+ oldPage = quick_page(page->frame);
+ memcpy(QUICK_PAGE, buf + count, min);
+ quick_page(oldPage);
+ release(&quickPageLock);
+ size -= min;
+ count += min;
+ }
+ return count;
+}
+
+/* Read a directory entry */
+int
+tmpfs_readdir(File *file, DirEnt *dent, off_t index)
+{
+ DirEntry *de;
+
+ if (!index--) {
+ dent->ino = file->inode->ino;
+ dent->type = DT_DIR;
+ dent->namelen = 2;
+ strncpy(dent->name, ".", dent->namelen);
+ return 0;
+ }
+
+ for (de = file->inode->dirEntries; de && index; de = de->next, index--);
+ if (!de)
+ return -ENOENT;
+ dent->ino = de->inode->ino;
+ if (S_ISBLK(de->inode->mode))
+ dent->type = DT_BLK;
+ if (S_ISCHR(de->inode->mode))
+ dent->type = DT_CHR;
+ if (S_ISDIR(de->inode->mode))
+ dent->type = DT_DIR;
+ if (S_ISFIFO(de->inode->mode))
+ dent->type = DT_FIFO;
+ if (S_ISLNK(de->inode->mode))
+ dent->type = DT_LNK;
+ if (S_ISREG(de->inode->mode))
+ dent->type = DT_REG;
+ if (S_ISSOCK(de->inode->mode))
+ dent->type = DT_SOCK;
+ dent->namelen = strnlen(de->name, NAME_MAX) + 1;
+ strncpy(dent->name, de->name, NAME_MAX);
+ return 0;
+}
+
+/* Open a file */
+int
+tmpfs_open(File *file)
+{
+ return 0;
+}