From 8506eb8d6abefa6d91468a8c350b60ce3321a53e Mon Sep 17 00:00:00 2001 From: Anatolij Gustschin Date: Thu, 15 Dec 2011 03:12:14 +0000 Subject: FAT: fix some issues in FAT write support code Writing a file to the FAT partition didn't work while a test using a CF card. The test was done on mpc5200 based board (powerpc). There is a number of problems in FAT write code: Compiler warning: fat_write.c: In function 'file_fat_write': fat_write.c:326: warning: 'counter' may be used uninitialized in this function fat_write.c:326: note: 'counter' was declared here 'l_filename' string is not terminated, so a file name with garbage at the end is used as a file name as shown by debug code. Return value of set_contents() is not checked properly so actually a file won't be written at all (as checked using 'fatls' after a write attempt with 'fatwrite' command). do_fat_write() doesn't return the number of written bytes if no error happened. However the return value of this function is used to show the number of written bytes in do_fat_fswrite(). The patch adds some debug code and fixes above mentioned problems and also fixes a typo in error output. NOTE: after a successful write to the FAT partition (under U-Boot) the partition was checked under Linux using fsck. The partition needed fixing FATs: -bash-3.2# fsck -a /dev/sda1 fsck 1.39 (29-May-2006) dosfsck 2.11, 12 Mar 2005, FAT32, LFN FATs differ but appear to be intact. Using first FAT. Performing changes. Signed-off-by: Anatolij Gustschin Cc: Donggeun Kim Cc: Aaron Williams Acked-by: Donggeun Kim --- fs/fat/fat_write.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'fs/fat/fat_write.c') diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c index 4f1772f29a..3542b0bcbd 100644 --- a/fs/fat/fat_write.c +++ b/fs/fat/fat_write.c @@ -323,7 +323,7 @@ static void fill_dir_slot(fsdata *mydata, dir_entry **dentptr, const char *l_name) { dir_slot *slotptr = (dir_slot *)get_vfatname_block; - __u8 counter, checksum; + __u8 counter = 0, checksum; int idx = 0, ret; char s_name[16]; @@ -926,6 +926,7 @@ static int do_fat_write(const char *filename, void *buffer, int cursect; int root_cluster, ret = -1, name_len; char l_filename[VFAT_MAXLEN_BYTES]; + int write_size = size; dir_curclust = 0; @@ -985,7 +986,11 @@ static int do_fat_write(const char *filename, void *buffer, dentptr = (dir_entry *) do_fat_read_block; name_len = strlen(filename); + if (name_len >= VFAT_MAXLEN_BYTES) + name_len = VFAT_MAXLEN_BYTES - 1; + memcpy(l_filename, filename, name_len); + l_filename[name_len] = 0; /* terminate the string */ downcase(l_filename); startsect = mydata->rootdir_sect; @@ -1012,10 +1017,12 @@ static int do_fat_write(const char *filename, void *buffer, } ret = set_contents(mydata, retdent, buffer, size); - if (ret) { + if (ret < 0) { printf("Error: writing contents\n"); goto exit; } + write_size = ret; + debug("attempt to write 0x%x bytes\n", write_size); /* Flush fat buffer */ ret = flush_fat_buffer(mydata); @@ -1029,7 +1036,7 @@ static int do_fat_write(const char *filename, void *buffer, get_dentfromdir_block, mydata->clust_size * mydata->sect_size); if (ret) { - printf("Error: wrinting directory entry\n"); + printf("Error: writing directory entry\n"); goto exit; } } else { @@ -1056,10 +1063,12 @@ static int do_fat_write(const char *filename, void *buffer, start_cluster, size, 0x20); ret = set_contents(mydata, empty_dentptr, buffer, size); - if (ret) { + if (ret < 0) { printf("Error: writing contents\n"); goto exit; } + write_size = ret; + debug("attempt to write 0x%x bytes\n", write_size); /* Flush fat buffer */ ret = flush_fat_buffer(mydata); @@ -1080,7 +1089,7 @@ static int do_fat_write(const char *filename, void *buffer, exit: free(mydata->fatbuf); - return ret; + return ret < 0 ? ret : write_size; } int file_fat_write(const char *filename, void *buffer, unsigned long maxsize) -- cgit v1.2.1