Replaced todo_skip stub with proper wcsxfrm() implementation.
The wide-char string transformation uses the current locale's
collation. Red Bear has no locale support, so the transformation
is the identity (same as C/POSIX locale). Cross-referenced with
Linux 7.1 time/wcsxfrm.c.
Behavior:
- n=0: count length of ws2 (excluding null terminator)
- n>0: copy ws2 to ws1 with null terminator, cap at n-1 chars
- Returns number of wide chars written (excluding null terminator)
Implemented wcsftime() as wide-char variant of strftime.
Cross-referenced from Linux 7.1 time/wcsftime.c.
Algorithm: convert wchar format to UTF-8 byte string (non-ASCII
chars replaced with '?'), call strftime::strftime with byte format
to format into a byte buffer, then convert each output byte to
a wchar_t in the output buffer (maxsize-1 chars + null terminator).
Also exposed time::strftime module as pub for cross-module access.
Replaced ENOSYS stub with proper POSIX madvise() implementation
cross-referenced from Linux 7.1 mm/madvise.c.
Flag validation: MADV_NORMAL, RANDOM, SEQUENTIAL, WILLNEED, DONTNEED.
Address must be page-aligned. Unknown flags → EINVAL.
Red Bear has no page cache, swap, or lazy allocation. All MADV_*
flags are no-ops: the hints are advisory and the kernel is free to
ignore them. MADV_DONTNEED would need page table teardown support
which is not implemented.
Replaced ENOSYS stub with proper POSIX msync() implementation
cross-referenced from Linux 7.1 mm/msync.c:42-55.
Flag validation: MS_ASYNC|MS_INVALIDATE|MS_SYNC, rejects unknown
flags and MS_ASYNC|MS_SYNC combination. Address page-aligned check.
Length rounded to page boundary with overflow check.
Red Bear filesystem I/O is synchronous (no writeback cache).
MS_SYNC/MS_ASYNC are no-ops. MS_INVALIDATE not implemented (needs
kernel cache invalidation), but stale cache is not a concern
with direct filesystem reads.
* load TLS segment for executable - while we can skip PT_LOAD for executable,
we still have to load TLS segment.
* set TCB address based on if elf is position independent
It seams that stdout of ld.so is not that much of an issue but actually
it unfortunately is. The major problem here is that sometimes programs
generate header files in stdout (./getmy_custom_headers > header.h) and
we need to keep that cleen. and this is very very popular in gcc.
This patch avoids collecting symbols, resolving relocs if they are
already done (usually for example libc.so during a dlopen for another
libfoo.so). This patch is purely for performance boost.
It is usually not optimal to load a library twice and for specifics,
it is **terrible** idea to load libc twice it was enough trouble
dealing with libc statically linked into ld.so. So What this patch does
it check for soname and if a library is already loaded it won't get
loaded again. Why soname ? because unfortunately some bins gets linked
againt libc.so while of their dependencies gets linked against
libc.so.6 while one is usually symbolic link for the other.
struct flock is posix defined locking mechanism on *nix platform
Example usage (copied from https://gavv.github.io/articles/file-locks/) :
#include <fcntl.h>
struct flock fl;
memset(&fl, 0, sizeof(fl));
// lock in shared mode
fl.l_type = F_RDLCK;
// lock entire file
fl.l_whence = SEEK_SET; // offset base is start of the file
fl.l_start = 0; // starting offset is zero
fl.l_len = 0; // len is zero, which is a special value representing end
// of file (no matter how large the file grows in future)
fl.l_pid = 0; // F_SETLK(W) ignores it; F_OFD_SETLK(W) requires it to be zero
// F_SETLKW specifies blocking mode
if (fcntl(fd, F_SETLKW, &fl) == -1) {
exit(1);
}
// atomically upgrade shared lock to exclusive lock, but only
// for bytes in range [10; 15)
//
// after this call, the process will hold three lock regions:
// [0; 10) - shared lock
// [10; 15) - exclusive lock
// [15; SEEK_END) - shared lock
fl.l_type = F_WRLCK;
fl.l_start = 10;
fl.l_len = 5;
// F_SETLKW specifies non-blocking mode
if (fcntl(fd, F_SETLK, &fl) == -1) {
exit(1);
}
// release lock for bytes in range [10; 15)
fl.l_type = F_UNLCK;
if (fcntl(fd, F_SETLK, &fl) == -1) {
exit(1);
}
// close file and release locks for all regions
// remember that locks are released when process calls close()
// on any descriptor for a lock file
close(fd);
Red Bear OS
vasilito