Lines Matching full:the
6 `Newlib`_ is a complete C library implementation written for the embedded
8 code form with Zephyr. Instead, the :ref:`toolchain_zephyr_sdk` includes a
14 the Newlib as a precompiled library.
16 Zephyr implements the "API hook" functions that are invoked by the C standard
17 library functions in the Newlib. These hook functions are implemented in
18 :file:`lib/libc/newlib/libc-hooks.c` and translate the library internal system
19 calls to the equivalent Zephyr API calls.
24 The Newlib included in the :ref:`toolchain_zephyr_sdk` comes in two versions:
30 The Newlib full variant (:file:`libc.a` and :file:`libm.a`) is the most capable
31 variant of the Newlib available in the Zephyr SDK, and supports almost all
33 performance over code size) and its footprint is significantly larger than the
36 This variant can be enabled by selecting the
37 :kconfig:option:`CONFIG_NEWLIB_LIBC` and de-selecting the
38 :kconfig:option:`CONFIG_NEWLIB_LIBC_NANO` in the application configuration
44 The Newlib nano variant (:file:`libc_nano.a` and :file:`libm_nano.a`) is the
45 size-optimized version of the Newlib, and supports all features that the full
46 variant supports except the new format specifiers introduced in C99, such as
47 the ``char``, ``long long`` type format specifiers (i.e. ``%hhX`` and
50 This variant can be enabled by selecting the
52 :kconfig:option:`CONFIG_NEWLIB_LIBC_NANO` in the application configuration
55 Note that the Newlib nano variant is not available for all architectures. The
56 availability of the nano variant is specified by the
67 The Newlib formatted input and output function implementation supports all
68 format specifiers defined by the C standard with the following exceptions:
73 * C99 format specifiers are not supported in the Newlib nano variant (i.e.
80 Newlib implements an internal heap allocator to manage the memory blocks used
81 by the standard dynamic memory management interface functions (for example,
84 The internal heap allocator implemented by the Newlib may vary across the
85 different types of the Newlib used. For example, the heap allocator implemented
86 in the Full Newlib (:file:`libc.a` and :file:`libm.a`) of the Zephyr SDK
87 requests larger memory chunks to the operating system and has a significantly
88 higher minimum memory requirement compared to that of the Nano Newlib
91 The only interface between the Newlib dynamic memory management functions and
92 the Zephyr-side libc hooks is the :c:func:`sbrk` function, which is used by the
93 Newlib to manage the size of the memory pool reserved for its internal heap
96 The :c:func:`_sbrk` hook function, implemented in :file:`libc-hooks.c`, handles
97 the memory pool size change requests from the Newlib and ensures that the
98 Newlib internal heap allocator memory pool size does not exceed the amount of
99 available memory space by returning an error when the system is out of memory.
101 When userspace is enabled, the Newlib internal heap allocator memory pool is
103 be accessed from the user mode threads.
105 The amount of memory space available for the Newlib heap depends on the system
108 * When MMU is enabled (:kconfig:option:`CONFIG_MMU` is selected), the amount of
109 memory space reserved for the Newlib heap is set by the size of the free
110 memory space returned by the :c:func:`k_mem_free_get` function or the
111 :kconfig:option:`CONFIG_NEWLIB_LIBC_MAX_MAPPED_REGION_SIZE`, whichever is the
114 * When MPU is enabled and the MPU requires power-of-two partition size and
116 set to a non-zero value), the amount of memory space reserved for the Newlib
117 heap is set by the :kconfig:option:`CONFIG_NEWLIB_LIBC_ALIGNED_HEAP_SIZE`.
119 * Otherwise, the amount of memory space reserved for the Newlib heap is equal
120 to the amount of free (unallocated) memory in the SRAM region.
122 The standard dynamic memory management interface functions implemented by the