[syslinux] [PATCH] Add ldisk.c32 Lua module

[Paul Emmerich]

ldisk.c32 is a Lua module that provides information about disks to Lua scripts
The example script com32/lua/test/detect_disks.lua uses it to implement some-
thing akin to 'disk.c32'.

The name 'ldisk.c32' was chosen to avoid a name-clash with 'disk.c32'.
---
 com32/lua/src/Makefile          |   1 +
 com32/lua/src/ldisk.c           | 103 ++++++++++++++++++++++++++++++++++++++++
 com32/lua/test/detect_disks.lua |  33 +++++++++++++
 3 files changed, 137 insertions(+)
 create mode 100644 com32/lua/src/ldisk.c
 create mode 100644 com32/lua/test/detect_disks.lua

diff --git a/com32/lua/src/Makefile b/com32/lua/src/Makefile
index c8a141f..97e5996 100644
--- a/com32/lua/src/Makefile
+++ b/com32/lua/src/Makefile
@@ -33,6 +33,7 @@ MODULES   += pci.c32
 MODULES   += syslinux.c32
 MODULES   += vesa.c32
 MODULES   += cmenu.c32
+MODULES   += ldisk.c32
 TESTFILES =
 
 OBJS	  = lua.o
diff --git a/com32/lua/src/ldisk.c b/com32/lua/src/ldisk.c
new file mode 100644
index 0000000..43ba8ff
--- /dev/null
+++ b/com32/lua/src/ldisk.c
@@ -0,0 +1,103 @@
+/* ----------------------------------------------------------------------- *
+ *
+ *   Copyright 2014 Paul Emmerich, First Colo GmbH - All Rights Reserved
+ *
+ *   Permission is hereby granted, free of charge, to any person
+ *   obtaining a copy of this software and associated documentation
+ *   files (the "Software"), to deal in the Software without
+ *   restriction, including without limitation the rights to use,
+ *   copy, modify, merge, publish, distribute, sublicense, and/or
+ *   sell copies of the Software, and to permit persons to whom
+ *   the Software is furnished to do so, subject to the following
+ *   conditions:
+ *
+ *   The above copyright notice and this permission notice shall
+ *   be included in all copies or substantial portions of the Software.
+ *
+ *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ *   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ *   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ *   OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * ----------------------------------------------------------------------- */
+
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <disk/geom.h>
+#include <disk/bootloaders.h>
+#include <disk/errno_disk.h>
+#include <disk/error.h>
+#include <disk/mbrs.h>
+#include <disk/msdos.h>
+#include <disk/partition.h>
+#include <disk/swsusp.h>
+#include <disk/read.h>
+
+#include "lua.h"
+#include "lauxlib.h"
+#include "lualib.h"
+
+#define SET_TABLE_STRING_INT(state, key, value) do {\
+		lua_pushstring((state), (key));\
+		lua_pushinteger((state), (value));\
+		lua_settable((state), -3);\
+} while(0);
+
+#define SET_TABLE_STRING_STRING(state, key, value) do {\
+		lua_pushstring((state), (key));\
+		lua_pushstring((state), (const char*) (value));\
+		lua_settable((state), -3);\
+} while(0);
+
+static int get_disks(lua_State* L) {
+	lua_newtable(L);
+	int i = 1;
+	for (int id = 0x80; id < 0xff; id++) {
+		struct driveinfo info = {
+			.disk = id,
+		};
+		if (get_drive_parameters(&info) == -1 // disk does not exist
+		|| !info.cbios) { // is not an hdd (-> a cdrom or whatever)
+		    continue;
+		}
+		lua_pushinteger(L, i);
+		lua_newtable(L);
+		SET_TABLE_STRING_INT(L, "id", id);
+		// legacy info
+		SET_TABLE_STRING_INT(L, "legacy_heads", info.legacy_max_head + 1);
+		SET_TABLE_STRING_INT(L, "legacy_cylinders", info.legacy_max_cylinder + 1);
+		SET_TABLE_STRING_INT(L, "legacy_sectors_per_track",
+			info.legacy_sectors_per_track + 1);
+		// edd
+		SET_TABLE_STRING_INT(L, "info", info.edd_params.info);
+		SET_TABLE_STRING_INT(L, "cylinders", info.edd_params.cylinders);
+		SET_TABLE_STRING_INT(L, "heads", info.edd_params.heads);
+		SET_TABLE_STRING_INT(L, "sectors", info.edd_params.sectors);
+		// size in mb as lua number type is uint32_t
+		SET_TABLE_STRING_INT(L, "size",
+			(uint64_t) info.edd_params.sectors * info.edd_params.bytes_per_sector
+			/ (1024 * 1024));
+		SET_TABLE_STRING_STRING(L, "host_bus", info.edd_params.host_bus_type);
+		SET_TABLE_STRING_STRING(L, "interface", info.edd_params.interface_type);
+		lua_settable(L, -3);
+		i++;
+    	}
+	return 1;
+}
+
+static const luaL_Reg disklib[] = {
+    {"get_disks", get_disks},
+    {NULL, NULL}
+};
+
+
+LUALIB_API int luaopen_ldisk(lua_State* L) {
+    luaL_newlib(L, disklib);
+    return 1;
+}
+
diff --git a/com32/lua/test/detect_disks.lua b/com32/lua/test/detect_disks.lua
new file mode 100644
index 0000000..add81be
--- /dev/null
+++ b/com32/lua/test/detect_disks.lua
@@ -0,0 +1,33 @@
+local disk = require "ldisk"
+
+local disks = disk.get_disks()
+
+local function printf(s, ...)
+	return print(s:format(...))
+end
+
+printf("Found %d disk%s", #disks, #disks ~= 1 and "s" or "")
+
+local prefixes = { [0] = "MiB", "GiB", "TiB" }
+local function get_size_string(size)
+	local prefix = 1
+	for i, v in ipairs(prefixes) do
+		local last_size = size
+		size = size / 1024
+		if size < 16 then
+			prefix = i - 1
+			size = last_size
+			break
+		end	
+	end
+	return size .. " " .. prefixes[prefix]
+end
+
+for i, v in ipairs(disks) do
+	printf("Id: %d, Size: %s", v.id, get_size_string(v.size))
+	for k, v in pairs(v) do
+		print(k, v)
+	end
+	printf("-----------------------------------------")
+end
+
-- 
1.8.4.2