Rename lib/ to src/ (better for Tab-completion)

1 files changed, 0 insertions, 132 deletions

diff --git a/lib/lock_release.asm b/lib/lock_release.asm
deleted file mode 100644
index f86caa2..0000000
--- a/lib/lock_release.asm
+++ /dev/null
@@ -1,132 +0,0 @@
-; Under MIT license, see /LICENSE.txt
-
-
-; Cheat sheet for Linux' x86_64 calling convention:
-;
-; - free to overwrite (caller should save them):
-;       rax, rcx, rdx, rsi, rdi, r8-r11, xmm0-xmm15
-; - caller expects be kept (callee should save them):
-;       rbx, rbp, r12-r15
-;
-; - for passing paramters to functions:
-;       rdi, rsi, rdx, rcx, r8, r9, xmm0-xmm7
-; - for getting return values from functions:
-;       rax, rdx, xmm0
-;
-; - for passing parameters to syscalls:
-;       rax, rdi, rsi, rdx, r10, r8, r9
-; - for getting return values from syscalls:
-;       rax, rdx
-; - overwritten by syscalls (all others preserved):
-;       rcx, r11
-
-
-section .text
-
-
-; Relevant system call IDs
-%define SYS_GETTID  186
-%define SYS_FUTEX   202
-
-; Relevant operations for futex
-%define FUTEX_UNLOCK_PI    7
-%define FUTEX_PRIVATE_FLAG 0x80
-
-; Relevant bits for futex dword
-%define FUTEX_TID_MASK   0x3fffffff
-%define FUTEX_OWNER_DIED 0x40000000
-%define FUTEX_WAITERS    0x80000000
-
-
-; Release an acquired lock if we're who acquired it. Argument:
-;	rdi: struct{u32,u32,u32}* = handle of lock to release
-; Returns zero on success, or a standard error code.
-global linen_lock_release
-linen_lock_release:
-		;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-		;;;; Check validity of argument ;;;;
-		;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-
-		; Return EINVAL if rdi is NULL or invalid
-		mov eax, -22 ; (EINVAL = -22)
-
-		test rdi, rdi
-		jz release_return ; rdi is NULL
-
-		; rdi is nonzero, so let's just assume it's a valid pointer;
-		; if that assumption is wrong we'll get a segmentation fault.
-		; But we don't yet trust that [rdi] is a valid lock handle!
-		; To verify this we check the canary value stored at [rdi + 8].
-		mov ecx, [rdi + 8]
-		cmp ecx, 0xCAFEBABE
-		jnz release_return
-
-		; Lock owners are identified by their TID; let's find ours.
-		; The gettid system call simply returns our Linux thread ID.
-		; See: man 2 gettid
-
-		; gettid: rax = system call ID
-		mov eax, SYS_GETTID
-		; gettid: rax = gettid()
-		syscall
-
-		; Save a copy of our TID (no need for an error check)
-		mov edx, eax
-
-		; Return EPERM if this lock currently doesn't belong to us
-		mov eax, -1 ; (EPERM = -1)
-
-		; Read the futex dword at [rdi] and keep its lowest 30 bits
-		mov ecx, [rdi]
-		and ecx, FUTEX_TID_MASK
-		; Those bits contain the owner's TID; it should be our TID
-		cmp ecx, edx
-		jne release_return
-
-		;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-		;;;; (Partially) release our lock ;;;;
-		;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-
-		; Decrement the recursion counter. If it's still > 1, we're done here.
-		dec dword [rdi + 4]
-		jnz release_success
-		; If it reaches 0, it's time for a full release by setting [rdi] to 0.
-
-		; Restore our saved TID to eax for "lock cmpxchg" below
-		mov eax, edx
-
-		; Atomically try to set the dword at [rdi] to 0 if it was equal to our TID.
-		; if ([rdi] == eax]) { [rdi] = 0; goto release_success; } else { eax = [rdi]; }
-		xor ecx, ecx
-		lock cmpxchg [rdi], ecx
-		je release_success
-
-		; We failed because [rdi] wasn't equal to our TID. In theory,
-		; that can mean only one thing: [rdi] = (edx | FUTEX_WAITERS).
-		; In that case we need to ask the kernel to wake up the threads
-		; who are waiting (via a futex system call) for [rdi] to change.
-		; See: man 2 futex
-
-		; futex: rdi = uaddr: address of the dword to announce for
-		; futex: rsi = futex_op: which futex operation we want:
-		; - FUTEX_UNLOCK_PI:    wake up one thread sleeping via FUTEX_LOCK_PI
-		; - FUTEX_PRIVATE_FLAG: this lock isn't shared with another process
-		mov esi, (FUTEX_UNLOCK_PI | FUTEX_PRIVATE_FLAG) ; futex: futex_op
-		; futex: rdx = val:     ignored when FUTEX_UNLOCK_PI is used
-		; futex: r10 = timeout: ignored when FUTEX_UNLOCK_PI is used
-		; futex: r8 = uaddr2:   ignored when FUTEX_UNLOCK_PI is used
-		; futex: r9 = val3:     ignored when FUTEX_UNLOCK_PI is used
-		; futex: rax = system call ID
-		mov eax, SYS_FUTEX
-		; futex: rax = futex(rdi, rsi, (rdx), (r10), (r8), (r9))
-		syscall
-
-		; Check result of futex: nonzero means failure
-		test rax, rax
-		jnz release_return
-
-	release_success:
-		xor eax, eax
-
-	release_return:
-		ret