Add options to kernelinfo(2).

kernel/kernel.cpp

@@ -80,6 +80,7 @@
 #include "kb/default-kblayout.h"
 #include "kb/kblayout.h"
 #include "kb/ps2.h"
+#include "kernelinfo.h"
 #include "logterminal.h"
 #include "mouse/ps2.h"
 #include "multiboot.h"
@@ -228,6 +229,9 @@ extern "C" void KernelInit(unsigned long magic, multiboot_info_t* bootinfo_p)
 		FreeKernelAddress(&alloc);
 	}
 
+	if ( !(kernel_options = strdup(cmdline ? cmdline : "")) )
+		Panic("Failed to allocate kernel command line");
+
 	int argmax = 1;
 	argv = new char*[argmax + 1];
 	if ( !argv )

kernel/kernelinfo.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2015, 2022 Jonas 'Sortie' Termansen.
+ * Copyright (c) 2012, 2015, 2022, 2023 Jonas 'Sortie' Termansen.
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -24,17 +24,22 @@
 #include <sortix/kernel/kernel.h>
 #include <sortix/kernel/syscall.h>
 
+#include "kernelinfo.h"
+
 #ifndef VERSIONSTR
 #define VERSIONSTR "unknown"
 #endif
 
 namespace Sortix {
 
+char* kernel_options;
+
 static const char* KernelInfo(const char* req)
 {
 	if ( strcmp(req, "name") == 0 ) { return BRAND_KERNEL_NAME; }
 	if ( strcmp(req, "version") == 0 ) { return VERSIONSTR; }
 	if ( strcmp(req, "tagline") == 0 ) { return BRAND_RELEASE_TAGLINE; }
+	if ( strcmp(req, "options") == 0 ) { return kernel_options; }
 	if ( strcmp(req, "builddate") == 0 ) { return __DATE__; }
 	if ( strcmp(req, "buildtime") == 0 ) { return __TIME__; }
 #if defined(__i386__) || defined(__x86_64__)

kernel/kernelinfo.h

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2023 Jonas 'Sortie' Termansen.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * kernelinfo.h
+ * Lets user-space query information about the kernel.
+ */
+
+#ifndef KERNELINFO_H
+#define KERNELINFO_H
+
+namespace Sortix {
+
+extern char* kernel_options;
+
+} // namespace Sortix
+
+#endif

utils/kernelinfo.1

@@ -21,6 +21,10 @@ The name of the current kernel.
 The version of the current kernel.
 .It Sy tagline
 The tagline (slogan) of the release.
+.It Sy options
+The
+.Xr kernel 7
+options.
 .It Sy builddate
 The date on which the current kernel was built.
 .It Sy buildtime
@@ -33,4 +37,5 @@ The firmware of the system (e.g. "bios" or "uefi")
 will exit 0 on success and non-zero otherwise.
 .Sh SEE ALSO
 .Xr uname 1 ,
-.Xr kernelinfo 2
+.Xr kernelinfo 2 ,
+.Xr kernel 7