syscalls: fchmodat

src/arch/x86_64/syscall.asm

@@ -30,7 +30,8 @@ extern syscall_mkdir
 extern syscall_munmap
 extern syscall_umask
 extern syscall_poll
-func_count equ 29
+extern syscall_fchmodat
+func_count equ 30
 
 
 func_table:
@@ -63,6 +64,7 @@ func_table:
 	dq syscall_munmap
 	dq syscall_umask
 	dq syscall_poll
+	dq syscall_fchmodat
 section .text
 global asm_syscall_entry
 

src/fs/devfs.c

@@ -77,8 +77,14 @@ static int devfs_getdirent(dirnode_t* node, dent_t* buff, size_t count, uintmax_
         return 0;
 }
 
+static int devfs_chmod(vnode_t* node, mode_t mode){
+	node->st.st_mode &= ~07777;
+	node->st.st_mode |= mode & 07777;
+	return 0;
+}
+
 static fscalls_t devfscalls = {
-	devfs_mount, devfs_unmount, devfs_open, devfs_close, devfs_mkdir, devfs_create, devfs_write, devfs_read, devfs_getdirent
+	devfs_mount, devfs_unmount, devfs_open, devfs_close, devfs_mkdir, devfs_create, devfs_write, devfs_read, devfs_getdirent, devfs_chmod
 };
 
 void devfs_init(){

src/fs/tmpfs.c

@@ -155,8 +155,14 @@ static int tmpfs_getdirent(dirnode_t* node, dent_t* buff, size_t count, uintmax_
 	return 0;
 }
 
+static int tmpfs_chmod(vnode_t* node, mode_t mode){
+	node->st.st_mode &= ~07777;
+	node->st.st_mode |= mode & 07777;
+	return 0;
+}
+
 static fscalls_t funcs = {
-	tmpfs_mount, tmpfs_unmount, tmpfs_open, tmpfs_close, tmpfs_mkdir, tmpfs_create, tmpfs_write, tmpfs_read, tmpfs_getdirent
+	tmpfs_mount, tmpfs_unmount, tmpfs_open, tmpfs_close, tmpfs_mkdir, tmpfs_create, tmpfs_write, tmpfs_read, tmpfs_getdirent, tmpfs_chmod
 };
 
 

src/fs/vfs.c

@@ -100,6 +100,21 @@ int vfs_isatty(vnode_t* node){
 	
 }
 
+int vfs_chmod(vnode_t* node, mode_t mode){
+	
+	if(!node->fs->calls->chmod)
+		return ENOSYS;
+
+	spinlock_acquire(&lock);
+
+	int ret = node->fs->calls->chmod(node, mode);
+
+	spinlock_release(&lock);
+
+	return ret;
+
+}
+
 int vfs_poll(vnode_t* node, pollfd* fd){
 	
 	switch(GETTYPE(node->st.st_mode)){

src/include/kernel/fd.h

@@ -30,6 +30,7 @@
 #define O_TMPFILE 020000000
 
 #define MAX_FD 512
+#define AT_FDCWD -100
 
 #include <stdint.h>
 #include <stddef.h>

src/include/kernel/vfs.h

@@ -61,6 +61,8 @@ typedef struct _fscalls_t {
 	int	 (*read)(int* error, vnode_t* node, void* buff, size_t count, size_t offset);
 	//	 get dir ents
 	int	 (*getdirent)(dirnode_t* node, dent_t* buff, size_t count, uintmax_t offset, size_t* readcount);
+	//	 change file mode
+	int 	 (*chmod)(vnode_t* node, mode_t mode);
 } fscalls_t;
 
 
@@ -76,6 +78,7 @@ int vfs_isatty(vnode_t* node);
 int vfs_getdirent(dirnode_t* node, dent_t* buff, size_t count, uintmax_t offset, size_t* readcount);
 int vfs_ioctl(vnode_t* node, unsigned long request, void* arg, int* result);
 int vfs_poll(vnode_t* node, pollfd* fd);
+int vfs_chmod(vnode_t* node, mode_t mode);
 
 void vfs_init();
 dirnode_t* vfs_root();

src/sys/syscalls/chmodat.c

@@ -0,0 +1,71 @@
+#include <kernel/syscalls.h>
+#include <kernel/vfs.h>
+#include <sys/types.h>
+#include <arch/cls.h>
+#include <kernel/fd.h>
+#include <kernel/sched.h>
+
+// flags is ignored for now
+
+syscallret syscall_fchmodat(int dirfd, const char* path, mode_t mode, int flags){
+	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;
+
+	dirnode_t* target;
+	fd_t* fd;
+
+	if(dirfd != AT_FDCWD){
+		
+		int err = fd_access(&proc->fdtable, &fd, dirfd);
+
+		if(err){
+			retv.errno = err;
+			return retv;
+		}
+		
+		if(GETTYPE(fd->mode) != TYPE_DIR){
+			retv.errno = ENOTDIR;
+			goto _fail;
+		}
+
+		target = fd->node;
+	}
+	else
+		target = proc->cwd;
+
+
+	vnode_t* node;
+	
+	retv.errno = vfs_open(&node, buff[0] == '/' ? proc->root : target, buff);
+
+	if(retv.errno)
+		goto _fail;
+	
+	retv.errno = vfs_chmod(node, mode);
+
+	vfs_close(node);
+
+	_fail:
+
+	if(dirfd != AT_FDCWD)
+		fd_release(fd);
+
+	retv.ret = retv.errno ? -1 : 0;
+	
+	return retv;
+
+}

src/sys/syscalls/fstatat.c

@@ -6,8 +6,6 @@
 #include <arch/spinlock.h>
 #include <string.h>
 
-#define AT_FDCWD -100
-
 syscallret syscall_fstatat(int ifd, char* path, stat* st, int flags){
 	syscallret retv;
 	retv.ret = -1;
@@ -67,13 +65,13 @@ syscallret syscall_fstatat(int ifd, char* path, stat* st, int flags){
 
 	vfs_close(node);
 
+	retv.ret = 0;
+
 	_fail:
 	
 	if(ifd != AT_FDCWD)
 		fd_release(fd);
 
-	retv.ret = 0;
-
 	return retv;
 
 }