Add FATFS Linux example

This allows a file on the Linux filesystem to be used as a FATFS file.

It also fixes a bug in `port.h` when opening file on a FATFS filesystem.

examples/sftpclient/sftpclient.c

@@ -1476,6 +1476,9 @@ THREAD_RETURN WOLFSSH_THREAD sftpclient_test(void* args)
 
     int main(int argc, char** argv)
     {
+        #ifdef WOLFSSH_FATFS
+            FATFS fs;
+        #endif
         func_args args;
 
         args.argc = argc;
@@ -1486,6 +1489,13 @@ THREAD_RETURN WOLFSSH_THREAD sftpclient_test(void* args)
             args.sftp_cb = NULL;
         #endif
 
+        #ifdef WOLFSSH_FATFS
+                if (f_mount(&fs, "0:", 1) != FR_OK) {
+                    fprintf(stderr, "Failed to mount filesystem\n");
+                    return 1;
+                }
+        #endif
+
         WSTARTTCP();
 
         #ifdef DEBUG_WOLFSSH
@@ -1499,6 +1509,10 @@ THREAD_RETURN WOLFSSH_THREAD sftpclient_test(void* args)
 
         wolfSSH_Cleanup();
 
+        #ifdef WOLFSSH_FATFS
+            f_mount(NULL, "0:", 1);
+        #endif
+
         #if defined(WOLFSSH_SFTP) && !defined(NO_WOLFSSH_CLIENT)
             return args.return_code;
         #else

ide/Linux-FATFS/.gitignore

@@ -0,0 +1 @@
+fatfs_image.img

ide/Linux-FATFS/Makefile

@@ -0,0 +1,26 @@
+# Compiler and flags
+CC = gcc
+CFLAGS = -g -Wall -O2 -fPIC
+LDFLAGS = -shared
+
+# Source files
+SRCS = ff.c ffunicode.c fatfs_example.c
+
+# Object files
+OBJS = $(SRCS:.c=.o)
+
+# Target library
+TARGET = libfatfs.so
+
+all: $(TARGET)
+
+$(TARGET): $(OBJS)
+	$(CC) $(LDFLAGS) -o $@ $^
+
+%.o: %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+clean:
+	rm -f $(OBJS) $(TARGET)
+
+.PHONY: all clean

ide/Linux-FATFS/README.md

@@ -0,0 +1,36 @@
+# FATFS Linux Example
+
+This is a FATFS example that uses a single file on the Linux filesystem as the
+FATFS file system.
+
+## Compiling Library
+
+To compile the FATFS library simply run `make`.
+
+## Setup filesystem
+
+The single file used for FATFS should be generated using:
+
+```sh
+dd if=/dev/zero of=fatfs_image.img bs=1M count=32
+mkdosfs fatfs_image.img
+```
+
+Note that this file will need to be local to wherever you execute anything using
+the library.
+
+## Compiling wolfSSH and wolfSSL
+
+### wolfSSL
+
+```sh
+./configure --enable-wolfssh --enable-intelasm --disable-crl --disable-examples --disable-filesystem CFLAGS="-DNO_WOLFSSL_DIR"
+```
+
+### wolfSSH
+
+```sh
+export LD_LIBRARY_PATH=ide/Linux-FATFS
+./configure --enable-sftp CFLAGS="-DWOLFSSH_FATFS -Iide/Linux-FATFS -DSTDIN_FILENO=0 -DPRINTF=printf -lfatfs"
+```
+

ide/Linux-FATFS/diskio.c

@@ -0,0 +1,229 @@
+/*-----------------------------------------------------------------------*/
+/* Low level disk I/O module SKELETON for FatFs     (C)ChaN, 2019        */
+/*-----------------------------------------------------------------------*/
+/* If a working storage control module is available, it should be        */
+/* attached to the FatFs via a glue function rather than modifying it.   */
+/* This is an example of glue functions to attach various exsisting      */
+/* storage control modules to the FatFs module with a defined API.       */
+/*-----------------------------------------------------------------------*/
+
+#include "ff.h"			/* Obtains integer types */
+#include "diskio.h"		/* Declarations of disk functions */
+
+/* Definitions of physical drive number for each drive */
+#define DEV_RAM		0	/* Example: Map Ramdisk to physical drive 0 */
+#define DEV_MMC		1	/* Example: Map MMC/SD card to physical drive 1 */
+#define DEV_USB		2	/* Example: Map USB MSD to physical drive 2 */
+
+
+/*-----------------------------------------------------------------------*/
+/* Get Drive Status                                                      */
+/*-----------------------------------------------------------------------*/
+
+DSTATUS disk_status (
+	BYTE pdrv		/* Physical drive nmuber to identify the drive */
+)
+{
+	DSTATUS stat;
+	int result;
+
+	switch (pdrv) {
+	case DEV_RAM :
+		result = RAM_disk_status();
+
+		// translate the reslut code here
+
+		return stat;
+
+	case DEV_MMC :
+		result = MMC_disk_status();
+
+		// translate the reslut code here
+
+		return stat;
+
+	case DEV_USB :
+		result = USB_disk_status();
+
+		// translate the reslut code here
+
+		return stat;
+	}
+	return STA_NOINIT;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Inidialize a Drive                                                    */
+/*-----------------------------------------------------------------------*/
+
+DSTATUS disk_initialize (
+	BYTE pdrv				/* Physical drive nmuber to identify the drive */
+)
+{
+	DSTATUS stat;
+	int result;
+
+	switch (pdrv) {
+	case DEV_RAM :
+		result = RAM_disk_initialize();
+
+		// translate the reslut code here
+
+		return stat;
+
+	case DEV_MMC :
+		result = MMC_disk_initialize();
+
+		// translate the reslut code here
+
+		return stat;
+
+	case DEV_USB :
+		result = USB_disk_initialize();
+
+		// translate the reslut code here
+
+		return stat;
+	}
+	return STA_NOINIT;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Read Sector(s)                                                        */
+/*-----------------------------------------------------------------------*/
+
+DRESULT disk_read (
+	BYTE pdrv,		/* Physical drive nmuber to identify the drive */
+	BYTE *buff,		/* Data buffer to store read data */
+	LBA_t sector,	/* Start sector in LBA */
+	UINT count		/* Number of sectors to read */
+)
+{
+	DRESULT res;
+	int result;
+
+	switch (pdrv) {
+	case DEV_RAM :
+		// translate the arguments here
+
+		result = RAM_disk_read(buff, sector, count);
+
+		// translate the reslut code here
+
+		return res;
+
+	case DEV_MMC :
+		// translate the arguments here
+
+		result = MMC_disk_read(buff, sector, count);
+
+		// translate the reslut code here
+
+		return res;
+
+	case DEV_USB :
+		// translate the arguments here
+
+		result = USB_disk_read(buff, sector, count);
+
+		// translate the reslut code here
+
+		return res;
+	}
+
+	return RES_PARERR;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Write Sector(s)                                                       */
+/*-----------------------------------------------------------------------*/
+
+#if FF_FS_READONLY == 0
+
+DRESULT disk_write (
+	BYTE pdrv,			/* Physical drive nmuber to identify the drive */
+	const BYTE *buff,	/* Data to be written */
+	LBA_t sector,		/* Start sector in LBA */
+	UINT count			/* Number of sectors to write */
+)
+{
+	DRESULT res;
+	int result;
+
+	switch (pdrv) {
+	case DEV_RAM :
+		// translate the arguments here
+
+		result = RAM_disk_write(buff, sector, count);
+
+		// translate the reslut code here
+
+		return res;
+
+	case DEV_MMC :
+		// translate the arguments here
+
+		result = MMC_disk_write(buff, sector, count);
+
+		// translate the reslut code here
+
+		return res;
+
+	case DEV_USB :
+		// translate the arguments here
+
+		result = USB_disk_write(buff, sector, count);
+
+		// translate the reslut code here
+
+		return res;
+	}
+
+	return RES_PARERR;
+}
+
+#endif
+
+
+/*-----------------------------------------------------------------------*/
+/* Miscellaneous Functions                                               */
+/*-----------------------------------------------------------------------*/
+
+DRESULT disk_ioctl (
+	BYTE pdrv,		/* Physical drive nmuber (0..) */
+	BYTE cmd,		/* Control code */
+	void *buff		/* Buffer to send/receive control data */
+)
+{
+	DRESULT res;
+	int result;
+
+	switch (pdrv) {
+	case DEV_RAM :
+
+		// Process of the command for the RAM drive
+
+		return res;
+
+	case DEV_MMC :
+
+		// Process of the command for the MMC/SD card
+
+		return res;
+
+	case DEV_USB :
+
+		// Process of the command the USB drive
+
+		return res;
+	}
+
+	return RES_PARERR;
+}
+