libfile: copy_file: explicitly truncate to final size ...

When possible truncate the destination file to the final size
explicitly. This allows for example ramfs to put the resulting
file contiguously into memory.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: copy_file: Fix calling discard_range ...

discard range is called with unitialized size argument. Call it after
stat() on the source filedescriptor. Also there's no point in continuing
when stat() on the source filedescriptor fails, so bail out in this
case.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

treewide: remove references to CREDITS ...

The CREDITS file was removed from barebox in 2015 by commit 6570288f2d97
("Remove the CREDITS file"). Remove references to it from several files.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

copy_file: call discard_range on destination file ...

discard the range in the output file we are going to overwrite anyway.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: copy_file: fix error handling ...

Before this, ret was falsely polluted, which caused a misleading error
message if the function bailed out at a later point.

Signed-off-by: Robert Karszniewicz <r.karszniewicz@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: Document that read_file() returns a terminated buffer ...

read_file() and read_file_2() return a '\0' terminated buffer to make
sure the buffer is usable as a string. Other code like read_file_line()
depends on this behaviour, so document it explicitly.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: fix typos ...

Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: have write_full return a descriptive error code ...

So far (p|)write_full has been returning -1 on error.
Some callers of write_full like imx_bbu_write_device print out the
function's return value on error, effectively rendering every printed
error message to be due to EPERM.

On the other hand, some callers like do_memcpy, use it correctly and
use errno. Sidestep the issue by having the function return -errno on
errors as well.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: Do not return 0 from write_full() ...

None of the callers of write_full() expect a zero return value. Given
how the documentation explicitly states that either all of the buffer
is going to be written out or an error generated, treat 0 retrun from
write() as a error, set errno to ENOSPC and return -1.

Same logic applies to pwrite_full() as well, so make the change there
while at it.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: Simplify read_full() ...

We can figure out the amount of written data by substracting 'insize'
from 'size' so there is no need to keep a separate counter for that.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/misc'

libfile: Make use of write_full() in copy_file() ...

Change copy_file() to rely on write_full() instead of re-implementing
it locally.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: Make failure path of open_and_lseek() consistent ...

Change the code of open_and_lseek() to make sure that opened file is
closed in every failure path as well. While at it make sure we don't
mix returning function return code and returning errno by opting to
always return the former.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: Fix incorrect lseek check in open_and_lseek() ...

We can't use "int" to capture output of lseek which is "loff_t", since
former does not cover all of the range of the values of the latter and
any pos >= 0xffff_ffff will result in a false positive "failure". To
avoid that replace the check to check that new position matches what
was requested.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: Error out if out of memory in read_file_2() ...

All other error cases in read_file_2() are handled gracefully, so
there shouldn't be any reason not do so for the case of trying to
allocate too much memory. This error path can be easily triggered
with:

barebox_update file-bigger-than-availible-ram.img

Currently this would result in a crash which is not really desirable
from user experience.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: Introduce pwrite_full() ...

Analogous to what we have with write()/write_full(), introduce a
lightweight wrapper around pwrite() that guarantees the either all
data is going to be written or a negative error code would be
returned.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: open_and_lseek: enlarge small files enough to make lseek possible ...

This makes the following do the expected thing:

	barebox@barebox sandbox:/ ls -l lala
	-rwxrwxrwx              4 lala
	barebox@barebox sandbox:/ mw -d lala 72 0

Without this patch mw dies with

	lseek: Invalid argument

memset, memcpy and probably others benefit in the same way.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: open_and_lseek: don't imply O_RDONLY ...

There are several users that pass O_RDWR or O_WRONLY in mode to
open_and_lseek() and use the resulting file descriptor for writing. This
is no real issue becauce O_RDONLY is 0 and so can be dropped without
any side effects.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: implement new helper write_file_flash() ...

Compared to write_file() this new function also calls erase() to be
suitable for flash devices.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/tftp-workaround'

libfile: Make write_file buffer const ...

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: implement a function to cache a file ...

Due to the nature of TFTP which can't lseek and due to the silliness
of our filesystem implementation which can't cache accesses we have to
manually cache files on TFTP filesystems sometimes. Make it easier
for them by providing a cache_file() function which copies the file
from TFTP to RAM.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: implement make_temp ...

Create a make_temp() function which creates a name for a temporary file.
Since we do not have any concurrency in barebox we do not need to create
the file right away and can leave that to the caller. Unlike unix
mktemp the resulting filename is dynamically allocated and must be
freed by the caller.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

lib: libfile: Fix copying files to a non existing destination ...

If the destination file does not exist the stat call to check the file
type fails. Extend the check of the stat return value.
To allow to copy files to a new destination.

Fixes commit 0ec6bd3e1be8 ("libfile: copy_file: Only open
regular files with O_TRUNC")

Signed-off-by: Teresa Remmet <t.remmet@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: copy_file: Only open regular files with O_TRUNC ...

Device files can not truncate in the most cases. Check if the
destination is a regular file and open only those with O_TRUNC.

Signed-off-by: Teresa Remmet <t.remmet@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: Change write_full to be have const buf ...

write() uses a const pointer so write_full should do the same.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

string: Fix (v)asprintf prototypes ...

Our asprintf and vasprintf have different prototypes than the glibc
functions. This causes trouble when we want to share barebox code
with userspace code. Change the prototypes for (v)asprintf to match
the glibc prototypes. Since the current (v)asprintf are convenient
to use change the existing functions to b(v)asprintf.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

libfile: move open_and_lseek() to libfile ...

libfile is a collection of helpers for handling files. open_and_lseek()
is a perfect match for this, so move it there.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

lib: libfile: Do not ignore errors in close() ...

Some character devices may perform meaningful operations in their
implementation of close() -- a good example would be socfpga.c which
checks if the FPGA was programmed succesfully in it's close() method
-- so ignoring return value of this call may cause false positives in
checking exit status for success.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

read_file_2(): drop unnecessary 'else' ...

Signed-off-by: Alexander Smirnov <alllecs@yandex.ru>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>