Read/write VFAT support from Rockbox-3.3 FAT stack

Add read/write VFAT support from Rockbox-3.3 FAT stack.
It should be also applicable to the unmodified 2009.11 U-Boot release.

Note that is was taken as is from Rockbox and from a older U-Boot
Rockbox patch. "checkpatch" shows very many coding style errors and
warnings, but it is tedious work to clean this up.

To make this patch work an additional mmc_block_write() board support
routine and the errno variable are needed.
Furthermore following defines in the board config header file:
	#define CONFIG_ROCKBOX_FAT	1
	#define CONFIG_U_BOOT		1
	#define CONFIG_SUPPORT_VFAT	1
	#define CONFIG_CMD_TREE_FAT
This will be added in a follow-up patch.

This patch is based on the patch from Etienne Carriere
<etienne.carriere@stericsson.com> for the U671x U-Boot:

This commit adds FAT write support to u-boot native read-only FAT code.
Commit initially applied on u-boot-v2009.01
(SHA1: 72d15e705bc3983884105cb7755c7ba80e74a0a5)

Based on FAT stack dumped from Rockbox package v3.1 (www.rockbox.org).
Based on initial Rockbox FAT stack integration in u-boot by Keith Outwater
(outwater@comcast.net).
Current porting is aligned with Rockbox v3.3 FAT stack.

Enable upon config switches:
CONFIG_CMD_FAT
CONFIG_ROCKBOX_FAT
CONFIG_CMD_TREE_FAT   (recommended)
CONFIG_SUPPORT_VFAT   (recommended)

C code APIs (from U-boot native FAT support):
int  fat_register_device(block_dev_desc_t *dev_desc, int part_no);
long file_fat_read(const char *path, void *buf, unsigned long maxsize);
int file_fat_ls(const char *dirname);
int file_fat_detectfs(void);

C code APIs (added by Rockbox FAT support):
long file_fat_write(const char *path, void *buf, unsigned long maxsize);
int file_fat_rm(const char *path);
int file_fat_rmdir(const char *path);
int file_fat_mkdir(const char *path);
int file_fat_cd(const char *path);
int file_fat_pwd(void);
int file_fat_mv(const char *oldpath, const char *newpath);
unsigned int rockbox_fat_free(unsigned long size_kbyte);
unsigned int rockbox_fat_size(void);

Use "help fat" from u-boot console to see available commands.

ST-Ericsson ID: WP264488

Change-Id: I9afc29ecb80f9152bd8534bbf11e47e54cfad796
Signed-off-by: Michael Brandt <michael.brandt@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/3009

2 files changed, 56 insertions, 0 deletions

diff --git a/lib_generic/string.c b/lib_generic/string.c
index b375b8124..6e69457e5 100644
--- a/lib_generic/string.c
+++ b/lib_generic/string.c
@@ -307,6 +307,53 @@ char * strpbrk(const char * cs,const char * ct)
 }
 #endif
 
+#ifndef __HAVE_ARCH_STRTOK_R
+/**
+ * strtok - Split a string into tokens
+ * @s: The string to be searched
+ * @ct: The characters to search for
+ *
+ * Dumped from rockbox-3.1 strok.c:
+ *     Copyright (C) 2002 by Daniel Stenberg
+ *     $Id: strtok.c 17847 2008-06-28 18:10:04Z bagder $
+ */
+char *
+strtok_r(char *ptr, const char *sep, char **end)
+{
+    if (!ptr)
+        /* we got NULL input so then we get our last position instead */
+        ptr = *end;
+
+    /* pass all letters that are including in the separator string */
+    while (*ptr && strchr(sep, *ptr))
+        ++ptr;
+
+    if (*ptr) {
+        /* so this is where the next piece of string starts */
+        char *start = ptr;
+
+        /* set the end pointer to the first byte after the start */
+        *end = start + 1;
+
+        /* scan through the string to find where it ends, it ends on a
+           null byte or a character that exists in the separator string */
+        while (**end && !strchr(sep, **end))
+            ++*end;
+
+        if (**end) {
+            /* the end is not a null byte */
+            **end = '\0';  /* zero terminate it! */
+            ++*end;        /* advance last pointer to beyond the null byte */
+        }
+
+        return start; /* return the position where the string starts */
+    }
+
+    /* we ended up on a null byte, there are no more strings to find! */
+    return NULL;
+}
+#endif
+
 #ifndef __HAVE_ARCH_STRTOK
 /**
  * strtok - Split a string into tokens
diff --git a/lib_generic/vsprintf.c b/lib_generic/vsprintf.c
index 8c58a9366..3b282f130 100644
--- a/lib_generic/vsprintf.c
+++ b/lib_generic/vsprintf.c
@@ -133,6 +133,15 @@ static int skip_atoi(const char **s)
 	return i;
 }
 
+int atoi(const char *s)
+{
+	int i=0;
+
+	while (is_digit(*s))
+		i = i*10 + *(s++) - '0';
+	return i;
+}
+
 /* Decimal conversion is by far the most typical, and is used
  * for /proc and /sys data. This directly impacts e.g. top performance
  * with many processes running. We optimize it for speed