On 01/26/2014 08:52 AM, Simon Glass wrote:
Hi Stephen,
On 23 January 2014 12:57, Stephen Warren <swarren@wwwdotorg.org mailto:swarren@wwwdotorg.org> wrote:
From: Stephen Warren <swarren@nvidia.com <mailto:swarren@nvidia.com>> This hooks into the generic "file exists" support added in an earlier patch, and provides an implementation for the ext4 filesystem.
diff --git a/fs/fat/fat.c b/fs/fat/fat.c
@@ -808,7 +808,7 @@ __u8 do_fat_read_at_block[MAX_CLUSTSIZE] long do_fat_read_at(const char *filename, unsigned long pos, void *buffer, - unsigned long maxsize, int dols) + unsigned long maxsize, int dols, int dogetsize)I think it would be better to combine the three available operations (read, ls and getsize) into an enum and pass the required operation explicitly into this function in a single parameter.
I had originally thought that, but the implementation of the function changes the value of dols during operation. I suppose it would be possible to achieve that using bit-mask operations on the variable, but it seemed a bit cleaner to just make it a separate variable rather than using fields within a somewhat unrelated variable.
Would you still prefer to combine them into one:?
- ret = get_contents(mydata, dentptr, pos, buffer, maxsize); + if (dogetsize) + ret = FAT2CPU32(dentptr->size); + else +Doesn't this mean you are actually reading the contents here into a NULL buffer? At least I think it needs a comment as to why this works.
ret = get_contents(mydata, dentptr, pos, buffer, maxsize); debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
get_contents() is the function that actually reads the file content; everything before this point is simply parsing the directory entry for the file. So, no, I don't think the file content is read at all.
That implementation of dols!=0 is somewhat similar, although it does "goto exit" at a different location in the code.