When CONFIG_SYMTAB_ORDEREDBYNAME is selected most code will use
the ordered search function. When it is not selected no code will
use the ordered search function. This change merges the two
functions and varies its behaviour based on the config setting,
such that all callers can simply call the one search function
and get the best behaviour.
An additional configuration option allows leading underscores to
be stripped from symbols being relocated in loaded objects. This
allows toolchains which prefix C symbol with underscores to make
loadable ELF objects.
* The appropriate size of stack varies among archs.
E.g. for 64-bit sim, 2048 is way too small, especially when the task
happens to use host OS functionalities.
I plan to allow an arch provide its own default.
* I plan to use this to replace hardcoded "STACKSIZE = 2048" in APPDIR.
Provided changes add option (CONFIG_EXECFUNCS_GENERATE_SYSTEM_SYMTAB) to build complete list of available functions and syscalls automatically. The symbolic table is generated in form libsymtab.a which can be reused by application or directly pull in when "g_symtab" and "g_nsymbols" variables are requested by EXECFUNCS configuration.
I have tried to follow mechanisms for library compilation in different kernel protection modes but tested only flat no-MMU build. The basic assumption is that this library and libraries providing syscall stubs and C-library functions are available in user-space context and initial application (usually NSH) registers the symbol table through IOCTL. The table can be reused then by another applications in their address space as kernel allows. Simple for flat or protected mode, I am not sure if really support in MMU mode. It is highly probable that I have made some mistake, overlooked something, but functionality is optional (should not cause troubles in any mode if disabled) and main purpose is to lower memory overhead when more applications are loaded on memory constrained system which usually use direct kernel calling without protection or address space separation. If the table should be provided by kernel to applications then makefiles has to be adjusted.
binfmt/, libs/libc/unistd, and others: Rename CONFIG_EXECFUNCS_SYMTAB to CONFIG_EXECFUNCS_SYMTAB_ARRAY. Rename CONFIG_EXECFUNCS_NSYMBOLS to CONFIG_EXECFUNCS_NSYMBOLS_VAR. Unlike CONFIG_EXECFUNCS_NSYMBOLS, CONFIG_EXECFUNCS_NSYMBOLS_VAR holds the name of an 'int' variable that contains the number of symbols in the symbol table.
configs/sama5d4-ek: Partial update to knsh build instructions.
Squashed commit of the following:
libs/libxx: Fix some confusing in naming. If the directory is called libxx, then the library must be libxx.a (unless perhaps LIBCXX is selected).
libs/: Fix paths in moved library directories.
libs: Brute force move of libc, libnx, and libxx to libs. Cannot yet build it in that configuration.
