From b2746a5f014fb5b7b56855052cba7737074e9f33 Mon Sep 17 00:00:00 2001
From: Matheus <matheusuky@gmail.com>
Date: Sun, 16 Oct 2022 16:52:12 -0300
Subject: [PATCH] syscalls: mkdir and chroot

---
 src/arch/x86_64/syscall.asm |  6 ++++-
 src/sys/syscalls/chroot.c   | 52 +++++++++++++++++++++++++++++++++++++
 src/sys/syscalls/mkdir.c    | 26 ++++++++++++++++---
 3 files changed, 80 insertions(+), 4 deletions(-)
 create mode 100644 src/sys/syscalls/chroot.c

diff --git a/src/arch/x86_64/syscall.asm b/src/arch/x86_64/syscall.asm
index a82595db..c5710b74 100644
--- a/src/arch/x86_64/syscall.asm
+++ b/src/arch/x86_64/syscall.asm
@@ -32,7 +32,9 @@ extern syscall_umask
 extern syscall_poll
 extern syscall_fchmodat
 extern syscall_openat
-func_count equ 31
+extern syscall_chroot
+extern syscall_mkdirat
+func_count equ 33
 
 
 func_table:
@@ -67,6 +69,8 @@ func_table:
 	dq syscall_poll
 	dq syscall_fchmodat
 	dq syscall_openat
+	dq syscall_chroot
+	dq syscall_mkdirat
 section .text
 global asm_syscall_entry
 
diff --git a/src/sys/syscalls/chroot.c b/src/sys/syscalls/chroot.c
new file mode 100644
index 00000000..80fbb055
--- /dev/null
+++ b/src/sys/syscalls/chroot.c
@@ -0,0 +1,52 @@
+#include <kernel/syscalls.h>
+#include <kernel/vfs.h>
+#include <kernel/sched.h>
+#include <kernel/vmm.h>
+#include <arch/cls.h>
+
+syscallret syscall_chroot(const char* path){
+
+	syscallret retv;
+	retv.ret = -1;
+
+	if(path > USER_SPACE_END){
+		retv.errno = EFAULT;
+		return retv;
+	}
+	
+	size_t len = strlen(path);
+
+	char buff[len+1];
+	
+	strcpy(buff, path);
+
+	proc_t* proc = arch_getcls()->thread->proc;
+
+	vnode_t* vnode;
+
+	retv.errno = vfs_open(&vnode,
+		buff[0] == '/' ? proc->root : proc->cwd,
+		buff
+	);
+
+	if(retv.errno)
+		return retv;
+	
+	if(GETTYPE(vnode->st.st_mode) != TYPE_DIR){
+		retv.errno = ENOTDIR;
+		goto _ret;
+	}
+
+	dirnode_t* oldroot = proc->root;
+	proc->root = (dirnode_t*)vnode;
+
+	retv.errno = 0;
+	retv.ret = 0;
+
+	_ret:
+		
+	vfs_close(vnode);
+
+	return retv;
+	
+}
diff --git a/src/sys/syscalls/mkdir.c b/src/sys/syscalls/mkdir.c
index fad1d468..f0af2205 100644
--- a/src/sys/syscalls/mkdir.c
+++ b/src/sys/syscalls/mkdir.c
@@ -4,7 +4,7 @@
 #include <string.h>
 #include <sys/types.h>
 
-syscallret syscall_mkdir(const char* pathname, mode_t mode){
+syscallret syscall_mkdirat(int dirfd, const char* pathname, mode_t mode){
 	syscallret retv;
 	retv.ret = -1;
 
@@ -19,12 +19,32 @@ syscallret syscall_mkdir(const char* pathname, mode_t mode){
 	
 	strcpy(path, pathname);
 
-	retv.errno = vfs_mkdir(path[0] == '/' ? proc->root : proc->cwd, path, mode & ~proc->umask);
+	dirnode_t* target;
+	fd_t* targetfd;
+
+	if(dirfd != AT_FDCWD){
+		
+		retv.errno = fd_access(&proc->fdtable, &targetfd, dirfd);
+		if(retv.errno)
+			return retv;
+		
+		target = targetfd->node;
+
+	}
+	else target = proc->cwd;
+
+	retv.errno = vfs_mkdir(path[0] == '/' ? proc->root : target, path, mode & ~proc->umask);
 	
 	if(retv.errno == 0)
 		retv.ret = 0;
-	
+
+	if(dirfd != AT_FDCWD)
+		fd_release(targetfd);
 
 	return retv;
 	
 }
+
+syscallret syscall_mkdir(const char* pathname, mode_t mode){
+	return syscall_mkdirat(AT_FDCWD, pathname, mode);
+}