Add gnu-efi submodule for headers, don't link, just re-implement some functions

src/efi.c

@@ -0,0 +1,159 @@
+#include "efi.h"
+#include "util.h"
+
+// New implementations of some functions in gnu-efi.
+// These functions are designed to avoid other gnu-efi calls.
+
+EFI_STATUS LibLocateProtocol(IN EFI_GUID *ProtocolGuid, OUT VOID **Interface) {
+	EFI_HANDLE buffer[256];
+	UINTN size = sizeof(buffer);
+	if (!EFI_ERROR(BS->LocateHandle(ByProtocol, ProtocolGuid, NULL, &size, buffer))) {
+		for (int i = 0; i < size / sizeof(EFI_HANDLE); ++i) {
+			if (!EFI_ERROR(BS->HandleProtocol(buffer[i], ProtocolGuid, Interface))) {
+				return EFI_SUCCESS;
+			}
+		}
+	}
+	return EFI_NOT_FOUND;
+}
+
+EFI_DEVICE_PATH *FileDevicePath(IN EFI_HANDLE Device OPTIONAL, IN CHAR16 *FileName) {
+	EFI_DEVICE_PATH *old_path = 0;
+	if (!Device || EFI_ERROR(BS->HandleProtocol(Device, TmpGuidPtr((EFI_GUID) EFI_DEVICE_PATH_PROTOCOL_GUID), (void**)&old_path))) {
+		static EFI_DEVICE_PATH end_path = {END_DEVICE_PATH_TYPE, END_ENTIRE_DEVICE_PATH_SUBTYPE, {sizeof(end_path), 0}};
+		old_path = &end_path;
+	}
+	UINTN old_path_size = 0, instances = 0;
+	for (EFI_DEVICE_PATH *p0 = old_path;; p0 = NextDevicePathNode(p0)) {
+		old_path_size += DevicePathNodeLength(p0);
+		if (IsDevicePathEndType(p0)) {
+			instances += 1;
+		}
+		if (IsDevicePathEnd(p0)) {
+			break;
+		}
+	}
+
+	UINTN size_str = (StrLen(FileName) + 1) * sizeof(*FileName);
+	UINTN size_fdp = SIZE_OF_FILEPATH_DEVICE_PATH + size_str;
+
+	EFI_DEVICE_PATH *new_path;
+	if (EFI_ERROR(BS->AllocatePool(EfiBootServicesData, old_path_size + instances * size_fdp, (void**)&new_path))) {
+		return 0;
+	}
+
+	EFI_DEVICE_PATH *p1 = new_path;
+	for (EFI_DEVICE_PATH *p0 = old_path;; p0 = NextDevicePathNode(p0)) {
+		if (IsDevicePathEndType(p0)) {
+			*p1 = (EFI_DEVICE_PATH) {
+				.Type = MEDIA_DEVICE_PATH,
+				.SubType = MEDIA_FILEPATH_DP,
+				.Length = {size_fdp, size_fdp >> 8},
+			};
+			FILEPATH_DEVICE_PATH *f = (FILEPATH_DEVICE_PATH *) p1;
+			BS->CopyMem(f->PathName, FileName, size_str);
+			p1 = NextDevicePathNode(p1);
+		}
+		BS->CopyMem(p1, p0, DevicePathNodeLength(p0));
+		if (IsDevicePathEnd(p0)) {
+			break;
+		}
+		p1 = NextDevicePathNode(p1);
+	}
+
+	return new_path;
+}
+
+INTN CompareMem(IN CONST VOID *Dest, IN CONST VOID *Src, IN UINTN len) {
+	CONST UINT8 *d = Dest, *s = Src;
+	for (UINTN i = 0; i < len; ++i) {
+		if (d[i] != s[i]) {
+			return d[i] - s[i];
+		}
+	}
+	return 0;
+}
+
+void StrnCat(IN CHAR16* dest, IN CONST CHAR16* src, UINTN len) {
+	CHAR16* d = dest;
+	while (*d) {
+		++d;
+	}
+	while (len-- && *src) {
+		*d++ = *src++;
+	}
+	*d = 0;
+}
+
+UINTN StrLen(IN CONST CHAR16* s) {
+	UINTN i = 0;
+	while (*s++) {
+		++i;
+	}
+	return i;
+}
+
+INTN StriCmp(IN CONST CHAR16* s1, IN CONST CHAR16* s2) {
+	while (*s1 && *s2) {
+		CHAR16 c1 = *s1++, c2 = *s2++;
+		if (c1 >= 'A' && c1 <= 'Z') {
+			c1 += 'a' - 'A';
+		}
+		if (c2 >= 'A' && c2 <= 'Z') {
+			c2 += 'a' - 'A';
+		}
+		if (c1 != c2) {
+			return c1 - c2;
+		}
+	}
+	return *s1 - *s2;
+}
+
+INTN StrnCmp(IN CONST CHAR16* s1, IN CONST CHAR16* s2, UINTN len) {
+	while (*s1 && *s2 && len--) {
+		CHAR16 c1 = *s1++, c2 = *s2++;
+		if (c1 >= 'A' && c1 <= 'Z') {
+			c1 += 'a' - 'A';
+		}
+		if (c2 >= 'A' && c2 <= 'Z') {
+			c2 += 'a' - 'A';
+		}
+		if (c1 != c2) {
+			return c1 - c2;
+		}
+	}
+	return len ? *s1 - *s2 : 0;
+}
+
+INTN StrCmp(IN CONST CHAR16* s1, IN CONST CHAR16* s2) {
+	while (*s1 && *s2) {
+		if (*s1 != *s2) {
+			return *s1 - *s2;
+		}
+		++s1, ++s2;
+	}
+	return *s1 - *s2;
+}
+
+UINTN Atoi(IN CONST CHAR16* s) {
+	UINTN n = 0;
+	while (*s >= '0' && *s <= '9') {
+		n = n * 10 + *s++ - '0';
+	}
+	return n;
+}
+
+void *memset(void *s, int c, __SIZE_TYPE__ n) {
+	unsigned char *p = s;
+	while (n--)
+		*p++ = c;
+	return s;
+}
+
+void *memcpy(void *dest, const void *src, __SIZE_TYPE__ n) {
+	const unsigned char *q = src;
+	unsigned char *p = dest;
+	while (n--)
+		*p++ = *q++;
+	return dest;
+}