Revert "Drop darwin-user"

This reverts commit 0adb124659cfadf9f0b5c99874c476116f0cf74f.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user: Update Makefiles to current conventions.

(Evidently, the build system has been changed a fair bit since
darwin-user was deleted.)
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
Use -Werror=implicit-function-declaration when available.

These warnings ALMOST ALWAYS indicate that something is wrong,
and making them fatal also makes it a lot easier to fix link errors
on OS X 10.5, since the ld(1) there doesn't give line numbers.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
audio/mixeng_template.h: Move "inline" before "IN_T" to pacify GCC.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user/syscall.c: Make const-correct.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user/syscall.c: Add "static" where appropriate.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user: Deal with signal header churn in 10.5.

Add a new "struct target_sigaltstack" rather than trying to coax the system
headers to define "struct sigaltstack" like they did before.

Also switch from SA_DISABLE and SA_ONSTACK to SS_DISABLE and SS_ONSTACK,
since the latter exist in both the 10.4 and 10.5 SDKs.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user/qemu-types.h: Copy from linux-user/qemu-types.h
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user: Update to current lock_user()/unlock_user() interface.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user: Add missing mmap.c interfaces.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
user-exec.c: Get struct ucontext and co. from OS X 10.5 headers...

This is a kludge; it might be better to *test* __DARWIN_UNIX03
further down?
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user: Fix disas_symtab handling.

(At least, the compiler accepts it now.  I have yet to get anything
actually loaded, due to address space conflicts ...)
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user/qemu.h: Add missing "info" field to struct TaskState.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user: Add syscall_defs.h with TARGET_SIG*, etc. #defines.

These were demanded by gdbstub.c and copied from bsd-user/syscall_defs.h.

I used `ediff' to compare it with <sys/signal.h>, and Apple doesn't seem
to have made any interesting changes, though I was a bit amused to see
that they also still had the advertising clause in the BSD license text...
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user/syscalls.h: Deal with 10.4->10.5 syscall churn.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user/syscall.c: Call Mach traps using their public names.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user/main.c: Misc. fixes.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user/machload.c: Clarify comments on nlist_extended.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user/machload.c: Make static-correct.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>
darwin-user/machload.c: Add a few comments.
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Signed-off-by: Samuel Bronson <naesten@gmail.com>