91027d0a7a
From an abstract point of view, escape_special's counterpart,
unescape_special, already handles the unescaping of blackslashed double
quote sequences.
As a more practical example, printk indexing is an example case where
this is already practically useful. Compare an example with
`ESCAPE_SPECIAL | ESCAPE_SPACE`, with quotes not escaped:
[root@ktst ~]# grep drivers/pci/pci-stub.c:69 /sys/kernel/debug/printk/index/vmlinux
<4> drivers/pci/pci-stub.c:69 pci_stub_init "pci-stub: invalid ID string "%s"\n"
...and the same after this patch:
[root@ktst ~]# grep drivers/pci/pci-stub.c:69 /sys/kernel/debug/printk/index/vmlinux
<4> drivers/pci/pci-stub.c:69 pci_stub_init "pci-stub: invalid ID string \"%s\"\n"
One can of course, alternatively, use ESCAPE_APPEND with a quote in
@only, but without this patch quotes are coerced into hex or octal which
can hurt readability quite significantly.
I've checked uses of ESCAPE_SPECIAL and %pE across the codebase, and I'm
pretty confident that this shouldn't affect any stable interfaces.
Signed-off-by: Chris Down <chris@chrisdown.name>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/af144c5b75e41ce417386253ba2694456bc04118.1623775748.git.chris@chrisdown.name
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.