a try to add support of FreeRTOS riscV-64 (k210 cpu). first step

1 files changed, 1405 insertions, 0 deletions

diff --git a/libiot/spiffs/spiffs_hydrogen.c b/libiot/spiffs/spiffs_hydrogen.c
new file mode 100644
index 0000000..9ff3e7a
--- /dev/null
+++ b/libiot/spiffs/spiffs_hydrogen.c
@@ -0,0 +1,1405 @@
+/*
+ * spiffs_hydrogen.c
+ *
+ *  Created on: Jun 16, 2013
+ *      Author: petera
+ */
+
+#include "spiffs.h"
+#include "spiffs_nucleus.h"
+
+#if SPIFFS_FILEHDL_OFFSET
+#define SPIFFS_FH_OFFS(fs, fh)   ((fh) != 0 ? ((fh) + (fs)->cfg.fh_ix_offset) : 0)
+#define SPIFFS_FH_UNOFFS(fs, fh) ((fh) != 0 ? ((fh) - (fs)->cfg.fh_ix_offset) : 0)
+#else
+#define SPIFFS_FH_OFFS(fs, fh)   (fh)
+#define SPIFFS_FH_UNOFFS(fs, fh) (fh)
+#endif
+
+#if SPIFFS_CACHE == 1
+static s32_t spiffs_fflush_cache(spiffs *fs, spiffs_file fh);
+#endif
+
+#if SPIFFS_BUFFER_HELP
+u32_t SPIFFS_buffer_bytes_for_filedescs(spiffs *fs, u32_t num_descs) {
+  return num_descs * sizeof(spiffs_fd);
+}
+#if SPIFFS_CACHE
+u32_t SPIFFS_buffer_bytes_for_cache(spiffs *fs, u32_t num_pages) {
+  return sizeof(spiffs_cache) + num_pages * (sizeof(spiffs_cache_page) + SPIFFS_CFG_LOG_PAGE_SZ(fs));
+}
+#endif
+#endif
+
+u8_t SPIFFS_mounted(spiffs *fs) {
+  return SPIFFS_CHECK_MOUNT(fs);
+}
+
+s32_t SPIFFS_format(spiffs *fs) {
+#if SPIFFS_READ_ONLY
+  (void)fs;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  SPIFFS_API_CHECK_CFG(fs);
+  if (SPIFFS_CHECK_MOUNT(fs)) {
+    fs->err_code = SPIFFS_ERR_MOUNTED;
+    return -1;
+  }
+
+  s32_t res;
+  SPIFFS_LOCK(fs);
+
+  spiffs_block_ix bix = 0;
+  while (bix < fs->block_count) {
+    fs->max_erase_count = 0;
+    res = spiffs_erase_block(fs, bix);
+    if (res != SPIFFS_OK) {
+      res = SPIFFS_ERR_ERASE_FAIL;
+    }
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+    bix++;
+  }
+
+  SPIFFS_UNLOCK(fs);
+
+  return 0;
+#endif // SPIFFS_READ_ONLY
+}
+
+#if SPIFFS_USE_MAGIC && SPIFFS_USE_MAGIC_LENGTH && SPIFFS_SINGLETON==0
+
+s32_t SPIFFS_probe_fs(spiffs_config *config) {
+  s32_t res = spiffs_probe(config);
+  return res;
+}
+
+#endif // SPIFFS_USE_MAGIC && SPIFFS_USE_MAGIC_LENGTH && SPIFFS_SINGLETON==0
+
+s32_t SPIFFS_mount(spiffs *fs, spiffs_config *config, u8_t *work,
+    u8_t *fd_space, u32_t fd_space_size,
+    void *cache, u32_t cache_size,
+    spiffs_check_callback check_cb_f) {
+  void *user_data;
+  SPIFFS_LOCK(fs);
+  user_data = fs->user_data;
+  memset(fs, 0, sizeof(spiffs));
+  memcpy(&fs->cfg, config, sizeof(spiffs_config));
+  fs->user_data = user_data;
+  fs->block_count = SPIFFS_CFG_PHYS_SZ(fs) / SPIFFS_CFG_LOG_BLOCK_SZ(fs);
+  fs->work = &work[0];
+  fs->lu_work = &work[SPIFFS_CFG_LOG_PAGE_SZ(fs)];
+  memset(fd_space, 0, fd_space_size);
+  // align fd_space pointer to pointer size byte boundary
+  u8_t ptr_size = sizeof(void*);
+  u8_t addr_lsb = ((u8_t)(intptr_t)fd_space) & (ptr_size-1);
+  if (addr_lsb) {
+    fd_space += (ptr_size-addr_lsb);
+    fd_space_size -= (ptr_size-addr_lsb);
+  }
+  fs->fd_space = fd_space;
+  fs->fd_count = (fd_space_size/sizeof(spiffs_fd));
+
+  // align cache pointer to 4 byte boundary
+  addr_lsb = ((u8_t)(intptr_t)cache) & (ptr_size-1);
+  if (addr_lsb) {
+    u8_t *cache_8 = (u8_t *)cache;
+    cache_8 += (ptr_size-addr_lsb);
+    cache = cache_8;
+    cache_size -= (ptr_size-addr_lsb);
+  }
+  if (cache_size & (ptr_size-1)) {
+    cache_size -= (cache_size & (ptr_size-1));
+  }
+
+#if SPIFFS_CACHE
+  fs->cache = cache;
+  fs->cache_size = (cache_size > (SPIFFS_CFG_LOG_PAGE_SZ(fs)*32)) ? SPIFFS_CFG_LOG_PAGE_SZ(fs)*32 : cache_size;
+  spiffs_cache_init(fs);
+#endif
+
+  s32_t res;
+
+#if SPIFFS_USE_MAGIC
+  res = SPIFFS_CHECK_MAGIC_POSSIBLE(fs) ? SPIFFS_OK : SPIFFS_ERR_MAGIC_NOT_POSSIBLE;
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+#endif
+
+  fs->config_magic = SPIFFS_CONFIG_MAGIC;
+
+  res = spiffs_obj_lu_scan(fs);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  SPIFFS_DBG("page index byte len:         "_SPIPRIi"\n", (u32_t)SPIFFS_CFG_LOG_PAGE_SZ(fs));
+  SPIFFS_DBG("object lookup pages:         "_SPIPRIi"\n", (u32_t)SPIFFS_OBJ_LOOKUP_PAGES(fs));
+  SPIFFS_DBG("page pages per block:        "_SPIPRIi"\n", (u32_t)SPIFFS_PAGES_PER_BLOCK(fs));
+  SPIFFS_DBG("page header length:          "_SPIPRIi"\n", (u32_t)sizeof(spiffs_page_header));
+  SPIFFS_DBG("object header index entries: "_SPIPRIi"\n", (u32_t)SPIFFS_OBJ_HDR_IX_LEN(fs));
+  SPIFFS_DBG("object index entries:        "_SPIPRIi"\n", (u32_t)SPIFFS_OBJ_IX_LEN(fs));
+  SPIFFS_DBG("available file descriptors:  "_SPIPRIi"\n", (u32_t)fs->fd_count);
+  SPIFFS_DBG("free blocks:                 "_SPIPRIi"\n", (u32_t)fs->free_blocks);
+
+  fs->check_cb_f = check_cb_f;
+
+  fs->mounted = 1;
+
+  SPIFFS_UNLOCK(fs);
+
+  return 0;
+}
+
+void SPIFFS_unmount(spiffs *fs) {
+  if (!SPIFFS_CHECK_CFG(fs) || !SPIFFS_CHECK_MOUNT(fs)) return;
+  SPIFFS_LOCK(fs);
+  u32_t i;
+  spiffs_fd *fds = (spiffs_fd *)fs->fd_space;
+  for (i = 0; i < fs->fd_count; i++) {
+    spiffs_fd *cur_fd = &fds[i];
+    if (cur_fd->file_nbr != 0) {
+#if SPIFFS_CACHE
+      (void)spiffs_fflush_cache(fs, cur_fd->file_nbr);
+#endif
+      spiffs_fd_return(fs, cur_fd->file_nbr);
+    }
+  }
+  fs->mounted = 0;
+
+  SPIFFS_UNLOCK(fs);
+}
+
+s32_t SPIFFS_errno(spiffs *fs) {
+  return fs->err_code;
+}
+
+void SPIFFS_clearerr(spiffs *fs) {
+  fs->err_code = SPIFFS_OK;
+}
+
+s32_t SPIFFS_creat(spiffs *fs, const char *path, spiffs_mode mode) {
+#if SPIFFS_READ_ONLY
+  (void)fs; (void)path; (void)mode;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  (void)mode;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  if (strlen(path) > SPIFFS_OBJ_NAME_LEN - 1) {
+    SPIFFS_API_CHECK_RES(fs, SPIFFS_ERR_NAME_TOO_LONG);
+  }
+  SPIFFS_LOCK(fs);
+  spiffs_obj_id obj_id;
+  s32_t res;
+
+  res = spiffs_obj_lu_find_free_obj_id(fs, &obj_id, (const u8_t*)path);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  res = spiffs_object_create(fs, obj_id, (const u8_t*)path, 0, SPIFFS_TYPE_FILE, 0);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  SPIFFS_UNLOCK(fs);
+  return 0;
+#endif // SPIFFS_READ_ONLY
+}
+
+spiffs_file SPIFFS_open(spiffs *fs, const char *path, spiffs_flags flags, spiffs_mode mode) {
+  (void)mode;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  if (strlen(path) > SPIFFS_OBJ_NAME_LEN - 1) {
+    SPIFFS_API_CHECK_RES(fs, SPIFFS_ERR_NAME_TOO_LONG);
+  }
+  SPIFFS_LOCK(fs);
+
+  spiffs_fd *fd;
+  spiffs_page_ix pix;
+
+#if SPIFFS_READ_ONLY
+  // not valid flags in read only mode
+  flags &= ~(SPIFFS_WRONLY | SPIFFS_CREAT | SPIFFS_TRUNC);
+#endif // SPIFFS_READ_ONLY
+
+  s32_t res = spiffs_fd_find_new(fs, &fd, path);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_object_find_object_index_header_by_name(fs, (const u8_t*)path, &pix);
+  if ((flags & SPIFFS_O_CREAT) == 0) {
+    if (res < SPIFFS_OK) {
+      spiffs_fd_return(fs, fd->file_nbr);
+    }
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+
+  if (res == SPIFFS_OK &&
+      (flags & (SPIFFS_O_CREAT | SPIFFS_O_EXCL)) == (SPIFFS_O_CREAT | SPIFFS_O_EXCL)) {
+    // creat and excl and file exists - fail
+    res = SPIFFS_ERR_FILE_EXISTS;
+    spiffs_fd_return(fs, fd->file_nbr);
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+
+  if ((flags & SPIFFS_O_CREAT) && res == SPIFFS_ERR_NOT_FOUND) {
+#if !SPIFFS_READ_ONLY
+    spiffs_obj_id obj_id;
+    // no need to enter conflicting name here, already looked for it above
+    res = spiffs_obj_lu_find_free_obj_id(fs, &obj_id, 0);
+    if (res < SPIFFS_OK) {
+      spiffs_fd_return(fs, fd->file_nbr);
+    }
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+    res = spiffs_object_create(fs, obj_id, (const u8_t*)path, 0, SPIFFS_TYPE_FILE, &pix);
+    if (res < SPIFFS_OK) {
+      spiffs_fd_return(fs, fd->file_nbr);
+    }
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+    flags &= ~SPIFFS_O_TRUNC;
+#endif // !SPIFFS_READ_ONLY
+  } else {
+    if (res < SPIFFS_OK) {
+      spiffs_fd_return(fs, fd->file_nbr);
+    }
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+  res = spiffs_object_open_by_page(fs, pix, fd, flags, mode);
+  if (res < SPIFFS_OK) {
+    spiffs_fd_return(fs, fd->file_nbr);
+  }
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+#if !SPIFFS_READ_ONLY
+  if (flags & SPIFFS_O_TRUNC) {
+    res = spiffs_object_truncate(fd, 0, 0);
+    if (res < SPIFFS_OK) {
+      spiffs_fd_return(fs, fd->file_nbr);
+    }
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+#endif // !SPIFFS_READ_ONLY
+
+  fd->fdoffset = 0;
+
+  SPIFFS_UNLOCK(fs);
+
+  return SPIFFS_FH_OFFS(fs, fd->file_nbr);
+}
+
+spiffs_file SPIFFS_open_by_dirent(spiffs *fs, struct spiffs_dirent *e, spiffs_flags flags, spiffs_mode mode) {
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  spiffs_fd *fd;
+
+  s32_t res = spiffs_fd_find_new(fs, &fd, 0);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_object_open_by_page(fs, e->pix, fd, flags, mode);
+  if (res < SPIFFS_OK) {
+    spiffs_fd_return(fs, fd->file_nbr);
+  }
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+#if !SPIFFS_READ_ONLY
+  if (flags & SPIFFS_O_TRUNC) {
+    res = spiffs_object_truncate(fd, 0, 0);
+    if (res < SPIFFS_OK) {
+      spiffs_fd_return(fs, fd->file_nbr);
+    }
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+#endif // !SPIFFS_READ_ONLY
+
+  fd->fdoffset = 0;
+
+  SPIFFS_UNLOCK(fs);
+
+  return SPIFFS_FH_OFFS(fs, fd->file_nbr);
+}
+
+spiffs_file SPIFFS_open_by_page(spiffs *fs, spiffs_page_ix page_ix, spiffs_flags flags, spiffs_mode mode) {
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  spiffs_fd *fd;
+
+  s32_t res = spiffs_fd_find_new(fs, &fd, 0);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  if (SPIFFS_IS_LOOKUP_PAGE(fs, page_ix)) {
+    res = SPIFFS_ERR_NOT_A_FILE;
+    spiffs_fd_return(fs, fd->file_nbr);
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+
+  res = spiffs_object_open_by_page(fs, page_ix, fd, flags, mode);
+  if (res == SPIFFS_ERR_IS_FREE ||
+      res == SPIFFS_ERR_DELETED ||
+      res == SPIFFS_ERR_NOT_FINALIZED ||
+      res == SPIFFS_ERR_NOT_INDEX ||
+      res == SPIFFS_ERR_INDEX_SPAN_MISMATCH) {
+    res = SPIFFS_ERR_NOT_A_FILE;
+  }
+  if (res < SPIFFS_OK) {
+    spiffs_fd_return(fs, fd->file_nbr);
+  }
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+#if !SPIFFS_READ_ONLY
+  if (flags & SPIFFS_O_TRUNC) {
+    res = spiffs_object_truncate(fd, 0, 0);
+    if (res < SPIFFS_OK) {
+      spiffs_fd_return(fs, fd->file_nbr);
+    }
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+#endif // !SPIFFS_READ_ONLY
+
+  fd->fdoffset = 0;
+
+  SPIFFS_UNLOCK(fs);
+
+  return SPIFFS_FH_OFFS(fs, fd->file_nbr);
+}
+
+static s32_t spiffs_hydro_read(spiffs *fs, spiffs_file fh, void *buf, s32_t len) {
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  spiffs_fd *fd;
+  s32_t res;
+
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  if ((fd->flags & SPIFFS_O_RDONLY) == 0) {
+    res = SPIFFS_ERR_NOT_READABLE;
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+
+  if (fd->size == SPIFFS_UNDEFINED_LEN && len > 0) {
+    // special case for zero sized files
+    res = SPIFFS_ERR_END_OF_OBJECT;
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+
+#if SPIFFS_CACHE_WR
+  spiffs_fflush_cache(fs, fh);
+#endif
+
+  if (fd->fdoffset + len >= fd->size) {
+    // reading beyond file size
+    s32_t avail = fd->size - fd->fdoffset;
+    if (avail <= 0) {
+      SPIFFS_API_CHECK_RES_UNLOCK(fs, SPIFFS_ERR_END_OF_OBJECT);
+    }
+    res = spiffs_object_read(fd, fd->fdoffset, avail, (u8_t*)buf);
+    if (res == SPIFFS_ERR_END_OF_OBJECT) {
+      fd->fdoffset += avail;
+      SPIFFS_UNLOCK(fs);
+      return avail;
+    } else {
+      SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+      len = avail;
+    }
+  } else {
+    // reading within file size
+    res = spiffs_object_read(fd, fd->fdoffset, len, (u8_t*)buf);
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+  fd->fdoffset += len;
+
+  SPIFFS_UNLOCK(fs);
+
+  return len;
+}
+
+s32_t SPIFFS_read(spiffs *fs, spiffs_file fh, void *buf, s32_t len) {
+  s32_t res = spiffs_hydro_read(fs, fh, buf, len);
+  if (res == SPIFFS_ERR_END_OF_OBJECT) {
+    res = 0;
+  }
+  return res;
+}
+
+
+#if !SPIFFS_READ_ONLY
+static s32_t spiffs_hydro_write(spiffs *fs, spiffs_fd *fd, void *buf, u32_t offset, s32_t len) {
+  (void)fs;
+  s32_t res = SPIFFS_OK;
+  s32_t remaining = len;
+  if (fd->size != SPIFFS_UNDEFINED_LEN && offset < fd->size) {
+    s32_t m_len = MIN((s32_t)(fd->size - offset), len);
+    res = spiffs_object_modify(fd, offset, (u8_t *)buf, m_len);
+    SPIFFS_CHECK_RES(res);
+    remaining -= m_len;
+    u8_t *buf_8 = (u8_t *)buf;
+    buf_8 += m_len;
+    buf = buf_8;
+    offset += m_len;
+  }
+  if (remaining > 0) {
+    res = spiffs_object_append(fd, offset, (u8_t *)buf, remaining);
+    SPIFFS_CHECK_RES(res);
+  }
+  return len;
+
+}
+#endif // !SPIFFS_READ_ONLY
+
+s32_t SPIFFS_write(spiffs *fs, spiffs_file fh, void *buf, s32_t len) {
+#if SPIFFS_READ_ONLY
+  (void)fs; (void)fh; (void)buf; (void)len;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  spiffs_fd *fd;
+  s32_t res;
+  u32_t offset;
+
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  if ((fd->flags & SPIFFS_O_WRONLY) == 0) {
+    res = SPIFFS_ERR_NOT_WRITABLE;
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+
+  if ((fd->flags & SPIFFS_O_APPEND)) {
+    fd->fdoffset = fd->size == SPIFFS_UNDEFINED_LEN ? 0 : fd->size;
+  }
+
+  offset = fd->fdoffset;
+
+#if SPIFFS_CACHE_WR
+  if (fd->cache_page == 0) {
+    // see if object id is associated with cache already
+    fd->cache_page = spiffs_cache_page_get_by_fd(fs, fd);
+  }
+#endif
+  if (fd->flags & SPIFFS_O_APPEND) {
+    if (fd->size == SPIFFS_UNDEFINED_LEN) {
+      offset = 0;
+    } else {
+      offset = fd->size;
+    }
+#if SPIFFS_CACHE_WR
+    if (fd->cache_page) {
+      offset = MAX(offset, fd->cache_page->offset + fd->cache_page->size);
+    }
+#endif
+  }
+
+#if SPIFFS_CACHE_WR
+  if ((fd->flags & SPIFFS_O_DIRECT) == 0) {
+    if (len < (s32_t)SPIFFS_CFG_LOG_PAGE_SZ(fs)) {
+      // small write, try to cache it
+      u8_t alloc_cpage = 1;
+      if (fd->cache_page) {
+        // have a cached page for this fd already, check cache page boundaries
+        if (offset < fd->cache_page->offset || // writing before cache
+            offset > fd->cache_page->offset + fd->cache_page->size || // writing after cache
+            offset + len > fd->cache_page->offset + SPIFFS_CFG_LOG_PAGE_SZ(fs)) // writing beyond cache page
+        {
+          // boundary violation, write back cache first and allocate new
+          SPIFFS_CACHE_DBG("CACHE_WR_DUMP: dumping cache page "_SPIPRIpg" for fd "_SPIPRIfd":"_SPIPRIid", boundary viol, offs:"_SPIPRIi" size:"_SPIPRIi"\n",
+              fd->cache_page->ix, fd->file_nbr, fd->obj_id, fd->cache_page->offset, fd->cache_page->size);
+          res = spiffs_hydro_write(fs, fd,
+              spiffs_get_cache_page(fs, spiffs_get_cache(fs), fd->cache_page->ix),
+              fd->cache_page->offset, fd->cache_page->size);
+          spiffs_cache_fd_release(fs, fd->cache_page);
+          SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+        } else {
+          // writing within cache
+          alloc_cpage = 0;
+        }
+      }
+
+      if (alloc_cpage) {
+        fd->cache_page = spiffs_cache_page_allocate_by_fd(fs, fd);
+        if (fd->cache_page) {
+          fd->cache_page->offset = offset;
+          fd->cache_page->size = 0;
+          SPIFFS_CACHE_DBG("CACHE_WR_ALLO: allocating cache page "_SPIPRIpg" for fd "_SPIPRIfd":"_SPIPRIid"\n",
+              fd->cache_page->ix, fd->file_nbr, fd->obj_id);
+        }
+      }
+
+      if (fd->cache_page) {
+        u32_t offset_in_cpage = offset - fd->cache_page->offset;
+        SPIFFS_CACHE_DBG("CACHE_WR_WRITE: storing to cache page "_SPIPRIpg" for fd "_SPIPRIfd":"_SPIPRIid", offs "_SPIPRIi":"_SPIPRIi" len "_SPIPRIi"\n",
+            fd->cache_page->ix, fd->file_nbr, fd->obj_id,
+            offset, offset_in_cpage, len);
+        spiffs_cache *cache = spiffs_get_cache(fs);
+        u8_t *cpage_data = spiffs_get_cache_page(fs, cache, fd->cache_page->ix);
+        memcpy(&cpage_data[offset_in_cpage], buf, len);
+        fd->cache_page->size = MAX(fd->cache_page->size, offset_in_cpage + len);
+        fd->fdoffset += len;
+        SPIFFS_UNLOCK(fs);
+        return len;
+      } else {
+        res = spiffs_hydro_write(fs, fd, buf, offset, len);
+        SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+        fd->fdoffset += len;
+        SPIFFS_UNLOCK(fs);
+        return res;
+      }
+    } else {
+      // big write, no need to cache it - but first check if there is a cached write already
+      if (fd->cache_page) {
+        // write back cache first
+        SPIFFS_CACHE_DBG("CACHE_WR_DUMP: dumping cache page "_SPIPRIpg" for fd "_SPIPRIfd":"_SPIPRIid", big write, offs:"_SPIPRIi" size:"_SPIPRIi"\n",
+            fd->cache_page->ix, fd->file_nbr, fd->obj_id, fd->cache_page->offset, fd->cache_page->size);
+        res = spiffs_hydro_write(fs, fd,
+            spiffs_get_cache_page(fs, spiffs_get_cache(fs), fd->cache_page->ix),
+            fd->cache_page->offset, fd->cache_page->size);
+        spiffs_cache_fd_release(fs, fd->cache_page);
+        SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+        // data written below
+      }
+    }
+  }
+#endif
+
+  res = spiffs_hydro_write(fs, fd, buf, offset, len);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  fd->fdoffset += len;
+
+  SPIFFS_UNLOCK(fs);
+
+  return res;
+#endif // SPIFFS_READ_ONLY
+}
+
+s32_t SPIFFS_lseek(spiffs *fs, spiffs_file fh, s32_t offs, int whence) {
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  spiffs_fd *fd;
+  s32_t res;
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+#if SPIFFS_CACHE_WR
+  spiffs_fflush_cache(fs, fh);
+#endif
+
+  s32_t fileSize = fd->size == SPIFFS_UNDEFINED_LEN ? 0 : fd->size;
+
+  switch (whence) {
+  case SPIFFS_SEEK_CUR:
+    offs = fd->fdoffset+offs;
+    break;
+  case SPIFFS_SEEK_END:
+    offs = fileSize + offs;
+    break;
+  }
+
+  if ((offs > fileSize)) {
+    fd->fdoffset = fileSize;
+    res = SPIFFS_ERR_END_OF_OBJECT;
+  }
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  spiffs_span_ix data_spix = offs / SPIFFS_DATA_PAGE_SIZE(fs);
+  spiffs_span_ix objix_spix = SPIFFS_OBJ_IX_ENTRY_SPAN_IX(fs, data_spix);
+  if (fd->cursor_objix_spix != objix_spix) {
+    spiffs_page_ix pix;
+    res = spiffs_obj_lu_find_id_and_span(
+        fs, fd->obj_id | SPIFFS_OBJ_ID_IX_FLAG, objix_spix, 0, &pix);
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+    fd->cursor_objix_spix = objix_spix;
+    fd->cursor_objix_pix = pix;
+  }
+  fd->fdoffset = offs;
+
+  SPIFFS_UNLOCK(fs);
+
+  return offs;
+}
+
+s32_t SPIFFS_remove(spiffs *fs, const char *path) {
+#if SPIFFS_READ_ONLY
+  (void)fs; (void)path;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  if (strlen(path) > SPIFFS_OBJ_NAME_LEN - 1) {
+    SPIFFS_API_CHECK_RES(fs, SPIFFS_ERR_NAME_TOO_LONG);
+  }
+  SPIFFS_LOCK(fs);
+
+  spiffs_fd *fd;
+  spiffs_page_ix pix;
+  s32_t res;
+
+  res = spiffs_fd_find_new(fs, &fd, 0);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_object_find_object_index_header_by_name(fs, (const u8_t*)path, &pix);
+  if (res != SPIFFS_OK) {
+    spiffs_fd_return(fs, fd->file_nbr);
+  }
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_object_open_by_page(fs, pix, fd, 0,0);
+  if (res != SPIFFS_OK) {
+    spiffs_fd_return(fs, fd->file_nbr);
+  }
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_object_truncate(fd, 0, 1);
+  if (res != SPIFFS_OK) {
+    spiffs_fd_return(fs, fd->file_nbr);
+  }
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  SPIFFS_UNLOCK(fs);
+  return 0;
+#endif // SPIFFS_READ_ONLY
+}
+
+s32_t SPIFFS_fremove(spiffs *fs, spiffs_file fh) {
+#if SPIFFS_READ_ONLY
+  (void)fs; (void)fh;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  spiffs_fd *fd;
+  s32_t res;
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  if ((fd->flags & SPIFFS_O_WRONLY) == 0) {
+    res = SPIFFS_ERR_NOT_WRITABLE;
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+
+#if SPIFFS_CACHE_WR
+  spiffs_cache_fd_release(fs, fd->cache_page);
+#endif
+
+  res = spiffs_object_truncate(fd, 0, 1);
+
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  SPIFFS_UNLOCK(fs);
+
+  return 0;
+#endif // SPIFFS_READ_ONLY
+}
+
+static s32_t spiffs_stat_pix(spiffs *fs, spiffs_page_ix pix, spiffs_file fh, spiffs_stat *s) {
+  (void)fh;
+  spiffs_page_object_ix_header objix_hdr;
+  spiffs_obj_id obj_id;
+  s32_t res =_spiffs_rd(fs,  SPIFFS_OP_T_OBJ_IX | SPIFFS_OP_C_READ, fh,
+      SPIFFS_PAGE_TO_PADDR(fs, pix), sizeof(spiffs_page_object_ix_header), (u8_t *)&objix_hdr);
+  SPIFFS_API_CHECK_RES(fs, res);
+
+  u32_t obj_id_addr = SPIFFS_BLOCK_TO_PADDR(fs, SPIFFS_BLOCK_FOR_PAGE(fs , pix)) +
+      SPIFFS_OBJ_LOOKUP_ENTRY_FOR_PAGE(fs, pix) * sizeof(spiffs_obj_id);
+  res =_spiffs_rd(fs,  SPIFFS_OP_T_OBJ_LU | SPIFFS_OP_C_READ, fh,
+      obj_id_addr, sizeof(spiffs_obj_id), (u8_t *)&obj_id);
+  SPIFFS_API_CHECK_RES(fs, res);
+
+  s->obj_id = obj_id & ~SPIFFS_OBJ_ID_IX_FLAG;
+  s->type = objix_hdr.type;
+  s->size = objix_hdr.size == SPIFFS_UNDEFINED_LEN ? 0 : objix_hdr.size;
+  s->pix = pix;
+  strncpy((char *)s->name, (char *)objix_hdr.name, SPIFFS_OBJ_NAME_LEN);
+#if SPIFFS_OBJ_META_LEN
+  memcpy(s->meta, objix_hdr.meta, SPIFFS_OBJ_META_LEN);
+#endif
+
+  return res;
+}
+
+s32_t SPIFFS_stat(spiffs *fs, const char *path, spiffs_stat *s) {
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  if (strlen(path) > SPIFFS_OBJ_NAME_LEN - 1) {
+    SPIFFS_API_CHECK_RES(fs, SPIFFS_ERR_NAME_TOO_LONG);
+  }
+  SPIFFS_LOCK(fs);
+
+  s32_t res;
+  spiffs_page_ix pix;
+
+  res = spiffs_object_find_object_index_header_by_name(fs, (const u8_t*)path, &pix);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_stat_pix(fs, pix, 0, s);
+
+  SPIFFS_UNLOCK(fs);
+
+  return res;
+}
+
+s32_t SPIFFS_fstat(spiffs *fs, spiffs_file fh, spiffs_stat *s) {
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  spiffs_fd *fd;
+  s32_t res;
+
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+#if SPIFFS_CACHE_WR
+  spiffs_fflush_cache(fs, fh);
+#endif
+
+  res = spiffs_stat_pix(fs, fd->objix_hdr_pix, fh, s);
+
+  SPIFFS_UNLOCK(fs);
+
+  return res;
+}
+
+// Checks if there are any cached writes for the object id associated with
+// given filehandle. If so, these writes are flushed.
+#if SPIFFS_CACHE == 1
+static s32_t spiffs_fflush_cache(spiffs *fs, spiffs_file fh) {
+  (void)fs;
+  (void)fh;
+  s32_t res = SPIFFS_OK;
+#if !SPIFFS_READ_ONLY && SPIFFS_CACHE_WR
+
+  spiffs_fd *fd;
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES(fs, res);
+
+  if ((fd->flags & SPIFFS_O_DIRECT) == 0) {
+    if (fd->cache_page == 0) {
+      // see if object id is associated with cache already
+      fd->cache_page = spiffs_cache_page_get_by_fd(fs, fd);
+    }
+    if (fd->cache_page) {
+      SPIFFS_CACHE_DBG("CACHE_WR_DUMP: dumping cache page "_SPIPRIpg" for fd "_SPIPRIfd":"_SPIPRIid", flush, offs:"_SPIPRIi" size:"_SPIPRIi"\n",
+          fd->cache_page->ix, fd->file_nbr,  fd->obj_id, fd->cache_page->offset, fd->cache_page->size);
+      res = spiffs_hydro_write(fs, fd,
+          spiffs_get_cache_page(fs, spiffs_get_cache(fs), fd->cache_page->ix),
+          fd->cache_page->offset, fd->cache_page->size);
+      if (res < SPIFFS_OK) {
+        fs->err_code = res;
+      }
+      spiffs_cache_fd_release(fs, fd->cache_page);
+    }
+  }
+#endif
+
+  return res;
+}
+#endif
+
+s32_t SPIFFS_fflush(spiffs *fs, spiffs_file fh) {
+  (void)fh;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  s32_t res = SPIFFS_OK;
+#if !SPIFFS_READ_ONLY && SPIFFS_CACHE_WR
+  SPIFFS_LOCK(fs);
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+  res = spiffs_fflush_cache(fs, fh);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs,res);
+  SPIFFS_UNLOCK(fs);
+#endif
+
+  return res;
+}
+
+s32_t SPIFFS_close(spiffs *fs, spiffs_file fh) {
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+
+  s32_t res = SPIFFS_OK;
+  SPIFFS_LOCK(fs);
+
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+#if SPIFFS_CACHE
+  res = spiffs_fflush_cache(fs, fh);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+#endif
+  res = spiffs_fd_return(fs, fh);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  SPIFFS_UNLOCK(fs);
+
+  return res;
+}
+
+s32_t SPIFFS_rename(spiffs *fs, const char *old_path, const char *new_path) {
+#if SPIFFS_READ_ONLY
+  (void)fs; (void)old_path; (void)new_path;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  if (strlen(new_path) > SPIFFS_OBJ_NAME_LEN - 1 ||
+      strlen(old_path) > SPIFFS_OBJ_NAME_LEN - 1) {
+    SPIFFS_API_CHECK_RES(fs, SPIFFS_ERR_NAME_TOO_LONG);
+  }
+  SPIFFS_LOCK(fs);
+
+  spiffs_page_ix pix_old, pix_dummy;
+  spiffs_fd *fd;
+
+  s32_t res = spiffs_object_find_object_index_header_by_name(fs, (const u8_t*)old_path, &pix_old);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_object_find_object_index_header_by_name(fs, (const u8_t*)new_path, &pix_dummy);
+  if (res == SPIFFS_ERR_NOT_FOUND) {
+    res = SPIFFS_OK;
+  } else if (res == SPIFFS_OK) {
+    res = SPIFFS_ERR_CONFLICTING_NAME;
+  }
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_fd_find_new(fs, &fd, 0);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_object_open_by_page(fs, pix_old, fd, 0, 0);
+  if (res != SPIFFS_OK) {
+    spiffs_fd_return(fs, fd->file_nbr);
+  }
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_object_update_index_hdr(fs, fd, fd->obj_id, fd->objix_hdr_pix, 0, (const u8_t*)new_path,
+      0, 0, &pix_dummy);
+#if SPIFFS_TEMPORAL_FD_CACHE
+  if (res == SPIFFS_OK) {
+    spiffs_fd_temporal_cache_rehash(fs, old_path, new_path);
+  }
+#endif
+
+  spiffs_fd_return(fs, fd->file_nbr);
+
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  SPIFFS_UNLOCK(fs);
+
+  return res;
+#endif // SPIFFS_READ_ONLY
+}
+
+#if SPIFFS_OBJ_META_LEN
+s32_t SPIFFS_update_meta(spiffs *fs, const char *name, const void *meta) {
+#if SPIFFS_READ_ONLY
+  (void)fs; (void)name; (void)meta;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  spiffs_page_ix pix, pix_dummy;
+  spiffs_fd *fd;
+
+  s32_t res = spiffs_object_find_object_index_header_by_name(fs, (const u8_t*)name, &pix);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_fd_find_new(fs, &fd, 0);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_object_open_by_page(fs, pix, fd, 0, 0);
+  if (res != SPIFFS_OK) {
+    spiffs_fd_return(fs, fd->file_nbr);
+  }
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  res = spiffs_object_update_index_hdr(fs, fd, fd->obj_id, fd->objix_hdr_pix, 0, 0, meta,
+      0, &pix_dummy);
+
+  spiffs_fd_return(fs, fd->file_nbr);
+
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  SPIFFS_UNLOCK(fs);
+
+  return res;
+#endif // SPIFFS_READ_ONLY
+}
+
+s32_t SPIFFS_fupdate_meta(spiffs *fs, spiffs_file fh, const void *meta) {
+#if SPIFFS_READ_ONLY
+  (void)fs; (void)fh; (void)meta;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  s32_t res;
+  spiffs_fd *fd;
+  spiffs_page_ix pix_dummy;
+
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  if ((fd->flags & SPIFFS_O_WRONLY) == 0) {
+    res = SPIFFS_ERR_NOT_WRITABLE;
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  }
+
+  res = spiffs_object_update_index_hdr(fs, fd, fd->obj_id, fd->objix_hdr_pix, 0, 0, meta,
+      0, &pix_dummy);
+
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  SPIFFS_UNLOCK(fs);
+
+  return res;
+#endif // SPIFFS_READ_ONLY
+}
+#endif // SPIFFS_OBJ_META_LEN
+
+spiffs_DIR *SPIFFS_opendir(spiffs *fs, const char *name, spiffs_DIR *d) {
+  (void)name;
+
+  if (!SPIFFS_CHECK_CFG((fs))) {
+    (fs)->err_code = SPIFFS_ERR_NOT_CONFIGURED;
+    return 0;
+  }
+
+  if (!SPIFFS_CHECK_MOUNT(fs)) {
+    fs->err_code = SPIFFS_ERR_NOT_MOUNTED;
+    return 0;
+  }
+
+  d->fs = fs;
+  d->block = 0;
+  d->entry = 0;
+  return d;
+}
+
+static s32_t spiffs_read_dir_v(
+    spiffs *fs,
+    spiffs_obj_id obj_id,
+    spiffs_block_ix bix,
+    int ix_entry,
+    const void *user_const_p,
+    void *user_var_p) {
+  (void)user_const_p;
+  s32_t res;
+  spiffs_page_object_ix_header objix_hdr;
+  if (obj_id == SPIFFS_OBJ_ID_FREE || obj_id == SPIFFS_OBJ_ID_DELETED ||
+      (obj_id & SPIFFS_OBJ_ID_IX_FLAG) == 0) {
+    return SPIFFS_VIS_COUNTINUE;
+  }
+
+  spiffs_page_ix pix = SPIFFS_OBJ_LOOKUP_ENTRY_TO_PIX(fs, bix, ix_entry);
+  res = _spiffs_rd(fs, SPIFFS_OP_T_OBJ_LU2 | SPIFFS_OP_C_READ,
+      0, SPIFFS_PAGE_TO_PADDR(fs, pix), sizeof(spiffs_page_object_ix_header), (u8_t *)&objix_hdr);
+  if (res != SPIFFS_OK) return res;
+  if ((obj_id & SPIFFS_OBJ_ID_IX_FLAG) &&
+      objix_hdr.p_hdr.span_ix == 0 &&
+      (objix_hdr.p_hdr.flags & (SPIFFS_PH_FLAG_DELET | SPIFFS_PH_FLAG_FINAL | SPIFFS_PH_FLAG_IXDELE)) ==
+          (SPIFFS_PH_FLAG_DELET | SPIFFS_PH_FLAG_IXDELE)) {
+    struct spiffs_dirent *e = (struct spiffs_dirent*)user_var_p;
+    e->obj_id = obj_id;
+    strcpy((char *)e->name, (char *)objix_hdr.name);
+    e->type = objix_hdr.type;
+    e->size = objix_hdr.size == SPIFFS_UNDEFINED_LEN ? 0 : objix_hdr.size;
+    e->pix = pix;
+#if SPIFFS_OBJ_META_LEN
+  memcpy(e->meta, objix_hdr.meta, SPIFFS_OBJ_META_LEN);
+#endif
+    return SPIFFS_OK;
+  }
+  return SPIFFS_VIS_COUNTINUE;
+}
+
+struct spiffs_dirent *SPIFFS_readdir(spiffs_DIR *d, struct spiffs_dirent *e) {
+  if (!SPIFFS_CHECK_MOUNT(d->fs)) {
+    d->fs->err_code = SPIFFS_ERR_NOT_MOUNTED;
+    return 0;
+  }
+  SPIFFS_LOCK(d->fs);
+
+  spiffs_block_ix bix;
+  int entry;
+  s32_t res;
+  struct spiffs_dirent *ret = 0;
+
+  res = spiffs_obj_lu_find_entry_visitor(d->fs,
+      d->block,
+      d->entry,
+      SPIFFS_VIS_NO_WRAP,
+      0,
+      spiffs_read_dir_v,
+      0,
+      e,
+      &bix,
+      &entry);
+  if (res == SPIFFS_OK) {
+    d->block = bix;
+    d->entry = entry + 1;
+    e->obj_id &= ~SPIFFS_OBJ_ID_IX_FLAG;
+    ret = e;
+  } else {
+    d->fs->err_code = res;
+  }
+  SPIFFS_UNLOCK(d->fs);
+  return ret;
+}
+
+s32_t SPIFFS_closedir(spiffs_DIR *d) {
+  SPIFFS_API_CHECK_CFG(d->fs);
+  SPIFFS_API_CHECK_MOUNT(d->fs);
+  return 0;
+}
+
+s32_t SPIFFS_check(spiffs *fs) {
+#if SPIFFS_READ_ONLY
+  (void)fs;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  s32_t res;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  res = spiffs_lookup_consistency_check(fs, 0);
+
+  res = spiffs_object_index_consistency_check(fs);
+
+  res = spiffs_page_consistency_check(fs);
+
+  res = spiffs_obj_lu_scan(fs);
+
+  SPIFFS_UNLOCK(fs);
+  return res;
+#endif // SPIFFS_READ_ONLY
+}
+
+s32_t SPIFFS_info(spiffs *fs, u32_t *total, u32_t *used) {
+  s32_t res = SPIFFS_OK;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  u32_t pages_per_block = SPIFFS_PAGES_PER_BLOCK(fs);
+  u32_t blocks = fs->block_count;
+  u32_t obj_lu_pages = SPIFFS_OBJ_LOOKUP_PAGES(fs);
+  u32_t data_page_size = SPIFFS_DATA_PAGE_SIZE(fs);
+  u32_t total_data_pages = (blocks - 2) * (pages_per_block - obj_lu_pages) + 1; // -2 for spare blocks, +1 for emergency page
+
+  if (total) {
+    *total = total_data_pages * data_page_size;
+  }
+
+  if (used) {
+    *used = fs->stats_p_allocated * data_page_size;
+  }
+
+  SPIFFS_UNLOCK(fs);
+  return res;
+}
+
+s32_t SPIFFS_gc_quick(spiffs *fs, u16_t max_free_pages) {
+#if SPIFFS_READ_ONLY
+  (void)fs; (void)max_free_pages;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  s32_t res;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  res = spiffs_gc_quick(fs, max_free_pages);
+
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  SPIFFS_UNLOCK(fs);
+  return 0;
+#endif // SPIFFS_READ_ONLY
+}
+
+
+s32_t SPIFFS_gc(spiffs *fs, u32_t size) {
+#if SPIFFS_READ_ONLY
+  (void)fs; (void)size;
+  return SPIFFS_ERR_RO_NOT_IMPL;
+#else
+  s32_t res;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  res = spiffs_gc_check(fs, size);
+
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+  SPIFFS_UNLOCK(fs);
+  return 0;
+#endif // SPIFFS_READ_ONLY
+}
+
+s32_t SPIFFS_eof(spiffs *fs, spiffs_file fh) {
+  s32_t res;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+
+  spiffs_fd *fd;
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+#if SPIFFS_CACHE_WR
+  res = spiffs_fflush_cache(fs, fh);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+#endif
+
+  res = (fd->fdoffset >= (fd->size == SPIFFS_UNDEFINED_LEN ? 0 : fd->size));
+
+  SPIFFS_UNLOCK(fs);
+  return res;
+}
+
+s32_t SPIFFS_tell(spiffs *fs, spiffs_file fh) {
+  s32_t res;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+
+  spiffs_fd *fd;
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+#if SPIFFS_CACHE_WR
+  res = spiffs_fflush_cache(fs, fh);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+#endif
+
+  res = fd->fdoffset;
+
+  SPIFFS_UNLOCK(fs);
+  return res;
+}
+
+s32_t SPIFFS_set_file_callback_func(spiffs *fs, spiffs_file_callback cb_func) {
+  SPIFFS_LOCK(fs);
+  fs->file_cb_f = cb_func;
+  SPIFFS_UNLOCK(fs);
+  return 0;
+}
+
+#if SPIFFS_IX_MAP
+
+s32_t SPIFFS_ix_map(spiffs *fs,  spiffs_file fh, spiffs_ix_map *map,
+    u32_t offset, u32_t len, spiffs_page_ix *map_buf) {
+  s32_t res;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+
+  spiffs_fd *fd;
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  if (fd->ix_map) {
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, SPIFFS_ERR_IX_MAP_MAPPED);
+  }
+
+  map->map_buf = map_buf;
+  map->offset = offset;
+  // nb: spix range includes last
+  map->start_spix = offset / SPIFFS_DATA_PAGE_SIZE(fs);
+  map->end_spix = (offset + len) / SPIFFS_DATA_PAGE_SIZE(fs);
+  memset(map_buf, 0, sizeof(spiffs_page_ix) * (map->end_spix - map->start_spix + 1));
+  fd->ix_map = map;
+
+  // scan for pixes
+  res = spiffs_populate_ix_map(fs, fd, 0, map->end_spix - map->start_spix + 1);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  SPIFFS_UNLOCK(fs);
+  return res;
+}
+
+s32_t SPIFFS_ix_unmap(spiffs *fs,  spiffs_file fh) {
+  s32_t res;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+
+  spiffs_fd *fd;
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  if (fd->ix_map == 0) {
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, SPIFFS_ERR_IX_MAP_UNMAPPED);
+  }
+
+  fd->ix_map = 0;
+
+  SPIFFS_UNLOCK(fs);
+  return res;
+}
+
+s32_t SPIFFS_ix_remap(spiffs *fs, spiffs_file fh, u32_t offset) {
+  s32_t res = SPIFFS_OK;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  fh = SPIFFS_FH_UNOFFS(fs, fh);
+
+  spiffs_fd *fd;
+  res = spiffs_fd_get(fs, fh, &fd);
+  SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+
+  if (fd->ix_map == 0) {
+    SPIFFS_API_CHECK_RES_UNLOCK(fs, SPIFFS_ERR_IX_MAP_UNMAPPED);
+  }
+
+  spiffs_ix_map *map = fd->ix_map;
+
+  s32_t spix_diff = offset / SPIFFS_DATA_PAGE_SIZE(fs) - map->start_spix;
+  map->offset = offset;
+
+  // move existing pixes if within map offs
+  if (spix_diff != 0) {
+    // move vector
+    int i;
+    const s32_t vec_len = map->end_spix - map->start_spix + 1; // spix range includes last
+    map->start_spix += spix_diff;
+    map->end_spix += spix_diff;
+    if (spix_diff >= vec_len) {
+      // moving beyond range
+      memset(&map->map_buf, 0, vec_len * sizeof(spiffs_page_ix));
+      // populate_ix_map is inclusive
+      res = spiffs_populate_ix_map(fs, fd, 0, vec_len-1);
+      SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+    } else if (spix_diff > 0) {
+      // diff positive
+      for (i = 0; i < vec_len - spix_diff; i++) {
+        map->map_buf[i] = map->map_buf[i + spix_diff];
+      }
+      // memset is non-inclusive
+      memset(&map->map_buf[vec_len - spix_diff], 0, spix_diff * sizeof(spiffs_page_ix));
+      // populate_ix_map is inclusive
+      res = spiffs_populate_ix_map(fs, fd, vec_len - spix_diff, vec_len-1);
+      SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+    } else {
+      // diff negative
+      for (i = vec_len - 1; i >= -spix_diff; i--) {
+        map->map_buf[i] = map->map_buf[i + spix_diff];
+      }
+      // memset is non-inclusive
+      memset(&map->map_buf[0], 0, -spix_diff * sizeof(spiffs_page_ix));
+      // populate_ix_map is inclusive
+      res = spiffs_populate_ix_map(fs, fd, 0, -spix_diff - 1);
+      SPIFFS_API_CHECK_RES_UNLOCK(fs, res);
+    }
+
+  }
+
+  SPIFFS_UNLOCK(fs);
+  return res;
+}
+
+s32_t SPIFFS_bytes_to_ix_map_entries(spiffs *fs, u32_t bytes) {
+  SPIFFS_API_CHECK_CFG(fs);
+  // always add one extra page, the offset might change to the middle of a page
+  return (bytes + SPIFFS_DATA_PAGE_SIZE(fs) ) / SPIFFS_DATA_PAGE_SIZE(fs);
+}
+
+s32_t SPIFFS_ix_map_entries_to_bytes(spiffs *fs, u32_t map_page_ix_entries) {
+  SPIFFS_API_CHECK_CFG(fs);
+  return map_page_ix_entries * SPIFFS_DATA_PAGE_SIZE(fs);
+}
+
+#endif // SPIFFS_IX_MAP
+
+#if SPIFFS_TEST_VISUALISATION
+s32_t SPIFFS_vis(spiffs *fs) {
+  s32_t res = SPIFFS_OK;
+  SPIFFS_API_CHECK_CFG(fs);
+  SPIFFS_API_CHECK_MOUNT(fs);
+  SPIFFS_LOCK(fs);
+
+  int entries_per_page = (SPIFFS_CFG_LOG_PAGE_SZ(fs) / sizeof(spiffs_obj_id));
+  spiffs_obj_id *obj_lu_buf = (spiffs_obj_id *)fs->lu_work;
+  spiffs_block_ix bix = 0;
+
+  while (bix < fs->block_count) {
+    // check each object lookup page
+    int obj_lookup_page = 0;
+    int cur_entry = 0;
+
+    while (res == SPIFFS_OK && obj_lookup_page < (int)SPIFFS_OBJ_LOOKUP_PAGES(fs)) {
+      int entry_offset = obj_lookup_page * entries_per_page;
+      res = _spiffs_rd(fs, SPIFFS_OP_T_OBJ_LU | SPIFFS_OP_C_READ,
+          0, bix * SPIFFS_CFG_LOG_BLOCK_SZ(fs) + SPIFFS_PAGE_TO_PADDR(fs, obj_lookup_page), SPIFFS_CFG_LOG_PAGE_SZ(fs), fs->lu_work);
+      // check each entry
+      while (res == SPIFFS_OK &&
+          cur_entry - entry_offset < entries_per_page && cur_entry < (int)(SPIFFS_PAGES_PER_BLOCK(fs)-SPIFFS_OBJ_LOOKUP_PAGES(fs))) {
+        spiffs_obj_id obj_id = obj_lu_buf[cur_entry-entry_offset];
+        if (cur_entry == 0) {
+          spiffs_printf(_SPIPRIbl" ", bix);
+        } else if ((cur_entry & 0x3f) == 0) {
+          spiffs_printf("     ");
+        }
+        if (obj_id == SPIFFS_OBJ_ID_FREE) {
+          spiffs_printf(SPIFFS_TEST_VIS_FREE_STR);
+        } else if (obj_id == SPIFFS_OBJ_ID_DELETED) {
+          spiffs_printf(SPIFFS_TEST_VIS_DELE_STR);
+        } else if (obj_id & SPIFFS_OBJ_ID_IX_FLAG){
+          spiffs_printf(SPIFFS_TEST_VIS_INDX_STR(obj_id));
+        } else {
+          spiffs_printf(SPIFFS_TEST_VIS_DATA_STR(obj_id));
+        }
+        cur_entry++;
+        if ((cur_entry & 0x3f) == 0) {
+          spiffs_printf("\n");
+        }
+      } // per entry
+      obj_lookup_page++;
+    } // per object lookup page
+
+    spiffs_obj_id erase_count;
+    res = _spiffs_rd(fs, SPIFFS_OP_C_READ | SPIFFS_OP_T_OBJ_LU2, 0,
+        SPIFFS_ERASE_COUNT_PADDR(fs, bix),
+        sizeof(spiffs_obj_id), (u8_t *)&erase_count);
+    SPIFFS_CHECK_RES(res);
+
+    if (erase_count != (spiffs_obj_id)-1) {
+      spiffs_printf("\tera_cnt: "_SPIPRIi"\n", erase_count);
+    } else {
+      spiffs_printf("\tera_cnt: N/A\n");
+    }
+
+    bix++;
+  } // per block
+
+  spiffs_printf("era_cnt_max: "_SPIPRIi"\n", fs->max_erase_count);
+  spiffs_printf("last_errno:  "_SPIPRIi"\n", fs->err_code);
+  spiffs_printf("blocks:      "_SPIPRIi"\n", fs->block_count);
+  spiffs_printf("free_blocks: "_SPIPRIi"\n", fs->free_blocks);
+  spiffs_printf("page_alloc:  "_SPIPRIi"\n", fs->stats_p_allocated);
+  spiffs_printf("page_delet:  "_SPIPRIi"\n", fs->stats_p_deleted);
+  SPIFFS_UNLOCK(fs);
+  u32_t total, used;
+  SPIFFS_info(fs, &total, &used);
+  spiffs_printf("used:        "_SPIPRIi" of "_SPIPRIi"\n", used, total);
+  return res;
+}
+#endif