kernel: syscall: Add SYS_stat

Signed-off-by: Ian Moffett <ian@osmora.org>

5 files changed, 113 insertions, 0 deletions

diff --git a/sys/include/sys/stat.h b/sys/include/sys/stat.h
new file mode 100644
index 0000000..a59c2b9
--- /dev/null
+++ b/sys/include/sys/stat.h
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _SYS_STAT_H_
+#define _SYS_STAT_H_
+
+#include <sys/types.h>
+
+struct stat {
+    dev_t st_dev;
+    ino_t st_ino;
+    mode_t st_mode;
+    nlink_t st_nlink;
+    uid_t st_uid;
+    gid_t st_guid;
+    dev_t st_rdev;
+    off_t st_size;
+    time_t st_atime;
+    time_t st_mtime;
+    time_t st_ctime;
+};
+
+#endif  /* _SYS_STAT_H_ */
diff --git a/sys/include/sys/syscall.h b/sys/include/sys/syscall.h
index a4b12d3..b9e1d09 100644
--- a/sys/include/sys/syscall.h
+++ b/sys/include/sys/syscall.h
@@ -40,6 +40,7 @@
 #define SYS_open    2
 #define SYS_read    3
 #define SYS_close   4
+#define SYS_stat    5
 
 #if defined(_KERNEL)
 /* Syscall return value and arg type */
diff --git a/sys/include/sys/vfs.h b/sys/include/sys/vfs.h
index 776ee66..0ec190e 100644
--- a/sys/include/sys/vfs.h
+++ b/sys/include/sys/vfs.h
@@ -38,6 +38,7 @@
 scret_t sys_open(struct syscall_args *scargs);
 scret_t sys_close(struct syscall_args *args);
 scret_t sys_read(struct syscall_args *scargs);
+scret_t sys_stat(struct syscall_args *scargs);
 
 #endif  /* _KERNEL */
 #endif  /* !_SYS_VFS_H_ */
diff --git a/sys/kern/kern_syscall.c b/sys/kern/kern_syscall.c
index b36c6af..f4d9cb8 100644
--- a/sys/kern/kern_syscall.c
+++ b/sys/kern/kern_syscall.c
@@ -38,6 +38,7 @@ scret_t(*g_sctab[])(struct syscall_args *) = {
     sys_open,   /* SYS_open */
     sys_read,   /* SYS_read */
     sys_close,  /* SYS_close */
+    sys_stat,   /* SYS_stat */
 };
 
 const size_t MAX_SYSCALLS = NELEM(g_sctab);
diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c
index f4c5c59..0ef3d42 100644
--- a/sys/kern/vfs_syscalls.c
+++ b/sys/kern/vfs_syscalls.c
@@ -28,10 +28,61 @@
  */
 
 #include <sys/vfs.h>
+#include <sys/vnode.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+#include <sys/namei.h>
+#include <sys/stat.h>
+#include <sys/limits.h>
+#include <sys/errno.h>
 #include <sys/types.h>
 #include <sys/filedesc.h>
 #include <string.h>
 
+static int
+vfs_dostat(const char *path, struct stat *sbuf)
+{
+    char pathbuf[PATH_MAX];
+    struct vattr *attr;
+    struct stat st;
+    struct vnode *vp;
+    struct vop_getattr_args gattr;
+    struct nameidata nd;
+    int error;
+
+    if (sbuf == NULL || path == NULL) {
+        return -EINVAL;
+    }
+
+    if ((copyinstr(path, pathbuf, sizeof(path))) < 0) {
+        return -EFAULT;
+    }
+
+    nd.path = path;
+    nd.flags = 0;
+
+    if ((error = namei(&nd)) != 0) {
+        return error;
+    }
+
+    vp = nd.vp;
+    gattr.vp = vp;
+    error = vfs_vop_getattr(vp, &gattr);
+
+    if (error != 0) {
+        return error;
+    }
+
+    attr = gattr.res;
+    memset(&st, VNOVAL, sizeof(st));
+
+    /* Copy stat data to userspace statbuf */
+    st.st_mode = attr->mode;
+    st.st_size = attr->size;
+    copyout(&st, sbuf, sizeof(*sbuf));
+    return 0;
+}
+
 /*
  * arg0: pathname
  * arg1: oflags
@@ -64,3 +115,13 @@ sys_read(struct syscall_args *scargs)
     return fd_read(scargs->arg0, (void *)scargs->arg1,
         scargs->arg2);
 }
+
+/*
+ * arg0: path
+ * arg1: buf
+ */
+scret_t
+sys_stat(struct syscall_args *scargs)
+{
+    return vfs_dostat((const char *)scargs->arg0, (void *)scargs->arg1);
+}