The gmtime() function returns a global result variable, and this
variable must be placed in the `z_libc_partition` when userspace is
enabled.
Since gmtime() makes use of a global variable and this results in a
footprint increase, this commit makes the time functions optional by
introducing `CONFIG_MINIMAL_LIBC_TIME` Kconfig and making them only
available when this option is enabled.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit introduces a new configuration called
`CONFIG_MINIMAL_LIBC_NON_REENTRANT_FUNCTIONS`, which enables the
traditional non-reentrant (i.e. not thread-safe) version of the C
standard library functions such as rand() and gmtime() when the
respective configs are enabled.
The non-reentrant functions make use of the globals and require an
additional memory partition (MPU region), which is scarce on low-end
devices, when CONFIG_USERSPACE=y.
The purpose of this option is to classify the MPU resource intensive
functions as a separate category and only enable them when there is a
demand for such.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
In order to bring consistency in-tree, migrate all lib code to the new
prefix <zephyr/...>. Note that the conversion has been scripted, refer
to zephyrproject-rtos#45388 for more details.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
This lets the toolchain header files determine how to use "restrict"
instead of having that decision down in the minimal libc library.
Signed-off-by: Bradley Bolen <bbolen@lexmark.com>
The identifiers used in the declaration and definition of a function
shall be identical [MISRAC2012-RULE_8_3-b]
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
struct tm has fields that were not being set by the implementation,
causing the test to fail when the uninitialized values were compared
with a static initialized result. Zero the structure before filling it.
Closes#17794
Signed-off-by: Peter A. Bigot <pab@pabigot.com>
Implement the conversion from UNIX time to broken-down civil time per
the gmtime() and gmtime_r() functions.
Signed-off-by: Peter A. Bigot <pab@pabigot.com>
