From 1d6c08478d453c93b3951514b516066f4e68f458 Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Wed, 20 Aug 2025 20:40:17 +0300
Subject: [PATCH] LibC: Fix sigsetjmp

the call from C sigsetjmp messed up rbp, now sigsetjmp is also written
in assembly.

I did not test the 32 bit code, just ported the tested 64 bit version
over :D
---
 userspace/libraries/LibC/arch/i686/setjmp.S   | 25 +++++++++++++++++--
 userspace/libraries/LibC/arch/x86_64/setjmp.S | 18 +++++++++++++
 userspace/libraries/LibC/setjmp.cpp           | 10 +-------
 3 files changed, 42 insertions(+), 11 deletions(-)

diff --git a/userspace/libraries/LibC/arch/i686/setjmp.S b/userspace/libraries/LibC/arch/i686/setjmp.S
index cbb318e57d..0779cd4ac9 100644
--- a/userspace/libraries/LibC/arch/i686/setjmp.S
+++ b/userspace/libraries/LibC/arch/i686/setjmp.S
@@ -19,7 +19,6 @@ setjmp:
 	xorl %eax, %eax
 
 	ret
-
  .size setjmp, . - setjmp
 
 // void longjmp(jmp_buf env, int val)
@@ -39,5 +38,27 @@ longjmp:
 	movl 16(%edx), %edi
 	movl 20(%edx), %esi
 	jmp *%ecx
-
  .size longjmp, . - longjmp
+
+// int sigsetjmp(sigjmp_buf env, int savemask)
+.global sigsetjmp
+sigsetjmp:
+	movl 4(%esp), %edx
+	movl 8(%esp), %ecx
+
+	movl %ecx, 24(%edx)
+	testl %ecx, %ecx
+	jz setjmp
+
+	leal 24(%edx), %edx
+	xorl %ecx, %ecx
+
+	subl $12, %esp
+	movl %edx, 8(%esp)
+	movl %ecx, 4(%esp)
+	movl %ecx, 0(%esp)
+	call pthread_sigmask
+	addl $12, %esp
+
+	jmp setjmp
+ .size sigsetjmp, . - sigsetjmp
diff --git a/userspace/libraries/LibC/arch/x86_64/setjmp.S b/userspace/libraries/LibC/arch/x86_64/setjmp.S
index da77a1fff7..bd6ed239be 100644
--- a/userspace/libraries/LibC/arch/x86_64/setjmp.S
+++ b/userspace/libraries/LibC/arch/x86_64/setjmp.S
@@ -38,3 +38,21 @@ longjmp:
 	movq 56(%rdi), %r15
 	jmp *%rcx
  .size longjmp, . - longjmp
+
+// int sigsetjmp(sigjmp_buf env, int savemask)
+.global sigsetjmp
+sigsetjmp:
+	movq %rsi, 64(%rdi)
+	testq %rsi, %rsi
+	jz setjmp
+
+	subq $8, %rsp
+	movq %rdi, (%rsp)
+	leaq 72(%rsi), %rdx
+	xorq %rsi, %rsi
+	call pthread_sigmask
+	movq (%rsp), %rdi
+	addq $8, %rsp
+
+	jmp setjmp
+ .size sigsetjmp, . - sigsetjmp
diff --git a/userspace/libraries/LibC/setjmp.cpp b/userspace/libraries/LibC/setjmp.cpp
index 0774b1b464..1edeec1130 100644
--- a/userspace/libraries/LibC/setjmp.cpp
+++ b/userspace/libraries/LibC/setjmp.cpp
@@ -7,13 +7,5 @@ void siglongjmp(sigjmp_buf env, int val)
 {
 	if (env[_JMP_BUF_REGS])
 		pthread_sigmask(SIG_SETMASK, reinterpret_cast<sigset_t*>(&env[_JMP_BUF_REGS + 1]), nullptr);
-	return longjmp(env, val);
-}
-
-int sigsetjmp(sigjmp_buf env, int savemask)
-{
-	env[_JMP_BUF_REGS] = savemask;
-	if (savemask)
-		pthread_sigmask(0, nullptr, reinterpret_cast<sigset_t*>(&env[_JMP_BUF_REGS + 1]));
-	return setjmp(env);
+	longjmp(env, val);
 }