fs/fat: fix case for FAT shortnames

Noticed when comparing our output to linux.  There are some lcase bits
which control whether filename and/or extension should be downcase'd.

Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Łukasz Majewski <lukma@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/fs/fat/fat.c b/fs/fat/fat.c
index c951d84f57a940dc4c94f871d957df9f74b99721..65873a2c2a86c8738d6157c93f3921e017b9b2c5 100644 (file)
--- a/fs/fat/fat.c
+++ b/fs/fat/fat.c
@@ -29,11 +29,13 @@ static const int vfat_enabled = 0;
 #endif
 
 /*
- * Convert a string to lowercase.
+ * Convert a string to lowercase.  Converts at most 'len' characters,
+ * 'len' may be larger than the length of 'str' if 'str' is NULL
+ * terminated.
  */
-static void downcase(char *str)
+static void downcase(char *str, size_t len)
 {
-       while (*str != '\0') {
+       while (*str != '\0' && len--) {
                *str = tolower(*str);
                str++;
        }
@@ -131,10 +133,13 @@ static void get_name(dir_entry *dirent, char *s_name)
        ptr = s_name;
        while (*ptr && *ptr != ' ')
                ptr++;
+       if (dirent->lcase & CASE_LOWER_BASE)
+               downcase(s_name, (unsigned)(ptr - s_name));
        if (dirent->ext[0] && dirent->ext[0] != ' ') {
-               *ptr = '.';
-               ptr++;
+               *ptr++ = '.';
                memcpy(ptr, dirent->ext, 3);
+               if (dirent->lcase & CASE_LOWER_EXT)
+                       downcase(ptr, 3);
                ptr[3] = '\0';
                while (*ptr && *ptr != ' ')
                        ptr++;
@@ -144,7 +149,6 @@ static void get_name(dir_entry *dirent, char *s_name)
                *s_name = '\0';
        else if (*s_name == aRING)
                *s_name = DELETED_FLAG;
-       downcase(s_name);
 }
 
 static int flush_dirty_fat_buffer(fsdata *mydata);

diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c
index 4ca024c2088038562f17e5904c46eacb1edc4518..d0468baf8ff5766f8508b18f9dc341b36e7d54eb 100644 (file)
--- a/fs/fat/fat_write.c
+++ b/fs/fat/fat_write.c
@@ -345,7 +345,7 @@ get_long_file_name(fsdata *mydata, int curclust, __u8 *cluster,
                *l_name = '\0';
        else if (*l_name == aRING)
                *l_name = DELETED_FLAG;
-       downcase(l_name);
+       downcase(l_name, INT_MAX);
 
        /* Return the real directory entry */
        *retdent = realdent;
@@ -981,7 +981,7 @@ static int do_fat_write(const char *filename, void *buffer, loff_t size,
 
        memcpy(l_filename, filename, name_len);
        l_filename[name_len] = 0; /* terminate the string */
-       downcase(l_filename);
+       downcase(l_filename, INT_MAX);
 
        startsect = mydata->rootdir_sect;
        retdent = find_directory_entry(mydata, startsect,

diff --git a/include/fat.h b/include/fat.h
index 83cd90017e56a069eb9a72a4ba5c372ee1790de3..0f589391242f7b7d5dfe03e56125b1afc685df76 100644 (file)
--- a/include/fat.h
+++ b/include/fat.h
@@ -128,10 +128,14 @@ typedef struct volume_info
        /* Boot sign comes last, 2 bytes */
 } volume_info;
 
+/* see dir_entry::lcase: */
+#define CASE_LOWER_BASE        8       /* base (name) is lower case */
+#define CASE_LOWER_EXT 16      /* extension is lower case */
+
 typedef struct dir_entry {
        char    name[8],ext[3]; /* Name and extension */
        __u8    attr;           /* Attribute bits */
-       __u8    lcase;          /* Case for base and extension */
+       __u8    lcase;          /* Case for name and ext (CASE_LOWER_x) */
        __u8    ctime_ms;       /* Creation time, milliseconds */
        __u16   ctime;          /* Creation time */
        __u16   cdate;          /* Creation date */