When we are running inside of a user namespace getuid() will return a
non-zero uid. So let's check euid as well to make sure we correctly drop
capabilities
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

README: add LGTM

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

tree-wide: wipe alloca() from the codebase

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Switch to a static stack instead of allocating a new one. There's really
no point in doing all of the dance to get the current pagesize.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

The header defines a simple wrapper for free() that can be used with
gcc's and clang's __attribute__((__cleanup__(<cleanup-fun>))) macro.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

compiler: hardening

Warn if an extern declaration is encountered within a function.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Warn when macros __TIME__, __DATE__ or __TIMESTAMP__ are encountered as
they might prevent bit-wise-identical reproducible compilations.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Warn about left shift overflows. This warning is enabled by default in
C99 and C++11 modes (and newer).

-Wshift-overflow=2
This warning level also warns about left-shifting 1 into the sign bit,
unless C++14 mode (or newer) is active.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Warn if shift count >= width of type.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Do not warn whenever an #else or an #endif are followed by text.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

compiler: hardening

Warn whenever a local variable or type declaration shadows another
variable, parameter, type, class member (in C++), or instance variable
(in Objective-C) or whenever a built-in function is shadowed.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

-Wimplicit-fallthrough=5 doesn’t recognize any comments as fallthrough
comments, only attributes disable the warning.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Enable -Wformat plus additional format checks. Currently equivalent to
-Wformat -Wformat-nonliteral -Wformat-security -Wformat-y2k.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>