FAT on SPI Flash Library (#1809)

* First commit of FFat library

* Fixed reboot loops if no fat present. Added CMakeLists

* Functionalize the partition checks

* Cleanup, especially in format

* Dont format if mounted.  More wording cleanup

* 16M ffat should only be on 16M board

* Fix some casting issues that trip up the compiler when building as ESP-IDF component

libraries/FFat/src/FFat.cpp

@@ -0,0 +1,144 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "vfs_api.h"
+extern "C" {
+#include "esp_vfs_fat.h"
+#include "diskio.h"
+#include "diskio_wl.h"
+#include "vfs_fat_internal.h"
+}
+#include "FFat.h"
+
+using namespace fs;
+
+F_Fat::F_Fat(FSImplPtr impl)
+    : FS(impl)
+{}
+
+const esp_partition_t *check_ffat_partition(const char* label)
+{
+    const esp_partition_t* ck_part = esp_partition_find_first(
+       ESP_PARTITION_TYPE_DATA, ESP_PARTITION_SUBTYPE_DATA_FAT, label);
+    if (!ck_part) {
+        log_e("No FAT partition found with label %s", label);
+        return NULL;
+    }
+    return ck_part;
+}
+
+bool F_Fat::begin(bool formatOnFail, const char * basePath, uint8_t maxOpenFiles, const char * partitionLabel)
+{
+    if(_wl_handle){
+        log_w("Already Mounted!");
+        return true;
+    }     
+
+    if (!check_ffat_partition(partitionLabel)) return false;
+
+    esp_vfs_fat_mount_config_t conf = {
+      .format_if_mount_failed = formatOnFail,
+      .max_files = maxOpenFiles
+    };
+    esp_err_t err = esp_vfs_fat_spiflash_mount(basePath, partitionLabel, &conf, &_wl_handle);
+    if(err){
+        log_e("Mounting FFat partition failed! Error: %d", err);
+        return false;
+    }
+    _impl->mountpoint(basePath);
+    return true;
+}
+
+void F_Fat::end()
+{
+    if(_wl_handle){
+        esp_err_t err = esp_vfs_fat_spiflash_unmount(_impl->mountpoint(), _wl_handle);
+        if(err){
+            log_e("Unmounting FFat partition failed! Error: %d", err);
+            return;
+        }
+        _wl_handle = NULL;
+        _impl->mountpoint(NULL);
+    }
+}
+
+bool F_Fat::format(bool full_wipe, char* partitionLabel)
+{
+    esp_err_t result;
+    if(_wl_handle){
+        log_w("Already Mounted!");
+        return false;
+    }
+    wl_handle_t temp_handle;
+// Attempt to mount to see if there is already data
+    const esp_partition_t *ffat_partition = check_ffat_partition(partitionLabel);
+    if (!ffat_partition) return false;
+    result = wl_mount(ffat_partition, &temp_handle);
+
+    if (result == ESP_OK) {
+// Wipe disk- quick just wipes the FAT. Full zeroes the whole disk
+        uint32_t wipe_size = full_wipe ? wl_size(temp_handle) : 16384;
+        wl_erase_range(temp_handle, 0, wipe_size);
+        wl_unmount(temp_handle);
+    }
+// Now do a mount with format_if_fail (which it will)
+    esp_vfs_fat_mount_config_t conf = {
+      .format_if_mount_failed = true,
+      .max_files = 1
+    };
+    result = esp_vfs_fat_spiflash_mount("/format_ffat", partitionLabel, &conf, &temp_handle);
+    esp_vfs_fat_spiflash_unmount("/format_ffat", temp_handle);
+    return result;
+}
+
+size_t F_Fat::totalBytes()
+{
+    FATFS *fs;
+    DWORD free_clust, tot_sect, sect_size;
+
+    BYTE pdrv = ff_diskio_get_pdrv_wl(_wl_handle);
+    char drv[3] = {(char)(48+pdrv), ':', 0};
+    FRESULT res = f_getfree(drv, &free_clust, &fs);
+    tot_sect = (fs->n_fatent - 2) * fs->csize;
+    sect_size = CONFIG_WL_SECTOR_SIZE;
+    return tot_sect * sect_size;
+}
+
+size_t F_Fat::freeBytes()
+{
+
+    FATFS *fs;
+    DWORD free_clust, free_sect, sect_size;
+
+    BYTE pdrv = ff_diskio_get_pdrv_wl(_wl_handle);
+    char drv[3] = {(char)(48+pdrv), ':', 0};
+    FRESULT res = f_getfree(drv, &free_clust, &fs);
+    free_sect = free_clust * fs->csize;
+    sect_size = CONFIG_WL_SECTOR_SIZE;
+    return free_sect * sect_size;
+}
+
+bool F_Fat::exists(const char* path)
+{
+    File f = open(path, "r");
+    return (f == true) && !f.isDirectory();
+}
+
+bool F_Fat::exists(const String& path)
+{
+    return exists(path.c_str());
+}
+
+
+F_Fat FFat = F_Fat(FSImplPtr(new VFSImpl()));

libraries/FFat/src/FFat.h

@@ -0,0 +1,47 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#ifndef _FFAT_H_
+#define _FFAT_H_
+
+#include "FS.h"
+#include "wear_levelling.h"
+
+#define FFAT_WIPE_QUICK 0
+#define FFAT_WIPE_FULL 1
+#define FFAT_PARTITION_LABEL "ffat"
+
+namespace fs
+{
+
+class F_Fat : public FS
+{
+public:
+    F_Fat(FSImplPtr impl);
+    bool begin(bool formatOnFail=false, const char * basePath="/ffat", uint8_t maxOpenFiles=10, const char * partitionLabel = (char*)FFAT_PARTITION_LABEL);
+    bool format(bool full_wipe = FFAT_WIPE_QUICK, char* partitionLabel = (char*)FFAT_PARTITION_LABEL);
+    size_t totalBytes();
+    size_t freeBytes();
+    void end();
+    bool exists(const char* path);
+    bool exists(const String& path);
+
+private:
+    wl_handle_t _wl_handle;
+};
+
+}
+
+extern fs::F_Fat FFat;
+
+#endif /* _FFAT_H_ */