efilinux: Parse load options

efilinux expects to be called with the path of a kernel as its only
argument. If an argument is present, parse it and pass it to the
loader as the file to load and execute. If no arguments are present
display the proper syntax for calling efilinux.

Signed-off-by: Matt Fleming <matt.fleming@linux.intel.com>

1 files changed, 115 insertions, 3 deletions

diff --git a/entry.c b/entry.c
index 4f9cacf..9197bb1 100644
--- a/entry.c
+++ b/entry.c
@@ -35,9 +35,12 @@
 #include <efilib.h>
 #include "efilinux.h"
 #include "fs.h"
+#include "protocol.h"
 
 #define ERROR_STRING_LENGTH	32
 
+static CHAR16 *banner = L"efilinux loader\n";
+
 EFI_SYSTEM_TABLE *sys_table;
 EFI_BOOT_SERVICES *boot;
 EFI_RUNTIME_SERVICES *runtime;
@@ -148,6 +151,107 @@ static EFI_STATUS print_memory_map(void)
 	return err;
 }
 
+static EFI_STATUS
+parse_args(CHAR16 *options, UINT32 size, CHAR16 **name, char **cmdline)
+{
+	CHAR16 *n, *filename = NULL;
+	int i;
+
+	if (!options || size == 0)
+		goto fail;
+
+	/* Skip the first word, that's our name. */
+	for (i = 0; i < size && options[i] != ' '; i++)
+		;
+
+	/* No arguments */
+	if (i == size)
+		goto fail;
+
+	n = &options[++i];
+
+	while (n <= &options[size]) {
+		if (*n == '-') {
+			switch (*++n) {
+			case 'h':
+				goto fail;
+			case 'f':
+				n++;	/* Skip 'f' */
+
+				/* Skip whitespace */
+				while (*n == ' ')
+					n++;
+
+				filename = n;
+				i = 0;	
+				while (*n && *n != ' ' && *n != '\n') {
+					i++;
+					n++;
+				}
+				*n++ = '\0';
+
+				*name = malloc(i + 1);
+				if (!*name) {
+					Print(L"Unable to alloc filename memory\n");
+					goto fail;
+				}
+				*name[i--] = '\0';
+
+				StrCpy(*name, filename);
+				break;
+			case 'l':
+				list_boot_devices();
+				goto out;
+			case 'm':
+				print_memory_map();
+				n++;
+				break;
+			default:
+				Print(L"Unknown command-line switch\n");
+				goto fail;
+			}
+		} else {
+			char *s1;
+			CHAR16 *s2;
+			int j;
+
+			j = StrLen(n);
+			*cmdline = malloc(j + 1);
+			if (!*cmdline) {
+				Print(L"Unable to alloc cmdline memory\n");
+				goto fail;
+			}
+			
+			s1 = *cmdline;
+			s2 = n;
+
+			while (j--)
+				*s1++ = *s2++;
+
+			*s1 = '\0';
+
+			/* Consume the rest of the args */
+			n = &options[size] + 1;
+		}
+	}
+
+	if (!filename)
+		goto fail;
+
+	return EFI_SUCCESS;
+
+fail:
+	Print(L"usage: efilinux [-hlm] -f <filename> <args>\n\n");
+	Print(L"\t-h:             display this help menu\n");
+	Print(L"\t-l:             list boot devices\n");
+	Print(L"\t-m:             print memory map\n");
+	Print(L"\t-f <filename>:  image to load\n");
+	Print(L"Error");
+
+out:
+	return EFI_INVALID_PARAMETER;
+}
+
 /**
  * efi_main - The entry point for the OS loader image.
  * @image: firmware-allocated handle that identifies the image
@@ -158,6 +262,9 @@ efi_main(EFI_HANDLE image, EFI_SYSTEM_TABLE *_table)
 {
 	WCHAR *error_buf;
 	EFI_STATUS err;
+	EFI_LOADED_IMAGE *info;
+	CHAR16 *name;
+	char *cmdline;
 
 	InitializeLib(image, _table);
 	sys_table = _table;
@@ -167,13 +274,18 @@ efi_main(EFI_HANDLE image, EFI_SYSTEM_TABLE *_table)
 	if (CheckCrc(sys_table->Hdr.HeaderSize, &sys_table->Hdr) != TRUE)
 		return EFI_LOAD_ERROR;
 
-	Print(L"efilinux loader\n");
+	Print(banner);
 
-	err = print_memory_map();
+	err = fs_init();
 	if (err != EFI_SUCCESS)
 		goto failed;
 
-	err = fs_init();
+	err = handle_protocol(image, &LoadedImageProtocol, (void **)&info);
+	if (err != EFI_SUCCESS)
+		goto failed;
+
+	err = parse_args(info->LoadOptions, info->LoadOptionsSize,
+			 &name, &cmdline);
 	if (err != EFI_SUCCESS)
 		goto failed;