fat_io_lib port WIP

kernel/fs/fatfs.c

@@ -0,0 +1,139 @@
+#include <desc.h>
+#include <fs/fat1.h>
+#include <fs/fatfs.h>
+#include <fs/fatfs_ctx.h>
+#include <fs/path.h>
+#include <fs/vfs.h>
+#include <libk/align.h>
+#include <libk/minmax.h>
+#include <libk/printf.h>
+#include <libk/std.h>
+#include <libk/string.h>
+#include <mm/liballoc.h>
+#include <path_defs.h>
+#include <status.h>
+#include <sys/debug.h>
+#include <xdrv_device.h>
+
+static int fat1_diskio_read (struct fatfs_ctx* ctx, uint32_t sector, uint8_t* buffer,
+                             uint32_t sector_count) {
+  struct vfs_volume* volume = ctx->udata;
+  struct device* back_device = volume->back_device;
+
+  size_t sector_size;
+  size_t phys_sector, phys_sector_count;
+  int ret;
+
+  spin_lock (&back_device->lock);
+
+  ret = device_op (back_device, XDRV_GET_SECTOR_SIZE, NULL, NULL, &sector_size);
+  if (ret < 0) {
+    spin_unlock (&back_device->lock);
+    return -1;
+  }
+
+  vfs_translate (sector, sector_count, FAT_SECTOR_SIZE, sector_size, &phys_sector,
+                 &phys_sector_count);
+
+  ret = device_op (back_device, XDRV_READ, NULL, NULL, &phys_sector, &phys_sector_count, buffer);
+  if (ret < 0) {
+    spin_unlock (&back_device->lock);
+    return -1;
+  }
+
+  spin_unlock (&back_device->lock);
+
+  if (ret < 0)
+    return -1;
+  return 0;
+}
+
+int fatfs_mount (struct vfs_volume* volume, struct proc* proc, struct reschedule_ctx* rctx) {
+  (void)proc, (void)rctx;
+
+  struct fatfs_ctx* fatfs_ctx = malloc (sizeof (*fatfs_ctx));
+
+  if (fatfs_ctx == NULL)
+    return -ST_OOM_ERROR;
+
+  memset (fatfs_ctx, 0, sizeof (*fatfs_ctx));
+  fl_attach_media (fatfs_ctx, &fat1_diskio_read, NULL);
+
+  fatfs_ctx->udata = volume;
+  volume->udata = fatfs_ctx;
+
+  return ST_OK;
+}
+
+int fatfs_describe (struct vfs_volume* volume, const char* path, struct desc* desc) {
+  struct fatfs_ctx* fatfs_ctx = volume->udata;
+
+  if (fl_is_dir (fatfs_ctx, path)) {
+    FL_DIR dir;
+
+    if (fl_opendir (fatfs_ctx, path, &dir) == NULL)
+      return -ST_NOT_FOUND;
+
+    desc->type = FS_DIR;
+    desc->size = 0;
+
+    fl_dirent dirent;
+    while (fl_readdir (fatfs_ctx, &dir, &dirent) == 0)
+      desc->size++;
+
+    fl_closedir (fatfs_ctx, &dir);
+  } else {
+    FL_FILE* file = fl_fopen (fatfs_ctx, path, "r");
+
+    if (file == NULL)
+      return -ST_NOT_FOUND;
+
+    desc->type = FS_FILE;
+    desc->size = file->filelength;
+
+    fl_fclose (fatfs_ctx, file);
+  }
+
+  return ST_OK;
+}
+
+int fatfs_read (struct vfs_volume* volume, const char* path, uint8_t* buffer, size_t off,
+                size_t size) {
+  struct fatfs_ctx* fatfs_ctx = volume->udata;
+
+  FL_FILE* file = fl_fopen (fatfs_ctx, path, "wb+");
+
+  if (file == NULL)
+    return -ST_NOT_FOUND;
+
+  fl_fseek (fatfs_ctx, file, off, SEEK_SET);
+  fl_fread (fatfs_ctx, buffer, 1, size, file);
+
+  fl_fclose (fatfs_ctx, file);
+
+  return ST_OK;
+}
+
+int fatfs_read_dir_entry (struct vfs_volume* volume, const char* path, struct dir_entry* entry,
+                          size_t entry_num) {
+  struct fatfs_ctx* fatfs_ctx = volume->udata;
+  FL_DIR dir;
+
+  if (fl_opendir (fatfs_ctx, path, &dir) == NULL)
+    return -ST_NOT_FOUND;
+
+  fl_dirent dirent;
+  size_t dirent_num = 0;
+  while (fl_readdir (fatfs_ctx, &dir, &dirent) == 0) {
+    if (dirent_num == entry_num) {
+      strncat (entry->path, path, PATH_MAX);
+      strncat (entry->path, dirent.filename, PATH_MAX);
+      break;
+    }
+
+    dirent_num++;
+  }
+
+  fl_closedir (fatfs_ctx, &dir);
+  return ST_OK;
+}