util/cse*: Add cse_helpers.{c,h}

This change moves `read_member` and `write_member` helper functions
out of cse_fpt.c and cse_serger.c into cse_helpers.c to avoid
duplication.

BUG=b:189177186,b:189167923

Change-Id: I7b646b29c9058d892bb0fc9824ef1b4340d2510c
Signed-off-by: Furquan Shaikh <furquan@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/58201
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

util/cbfstool/Makefile.inc

@@ -100,12 +100,14 @@ include $(top)/util/cbfstool/fpt_formats/Makefile.inc
 cse_fpt_obj :=
 cse_fpt_obj += cse_fpt.o
 cse_fpt_obj += common.o
+cse_fpt_obj += cse_helpers.o
 cse_fpt_obj += $(foreach var, $(fpt_formats_obj), $(var))
 
 include $(top)/util/cbfstool/bpdt_formats/Makefile.inc
 cse_serger_obj :=
 cse_serger_obj += cse_serger.o
 cse_serger_obj += common.o
+cse_serger_obj += cse_helpers.o
 cse_serger_obj += $(foreach var, $(bpdt_formats_obj), $(var))
 
 TOOLCFLAGS ?= -Werror -Wall -Wextra -Wshadow

util/cbfstool/cse_fpt.c

@@ -64,30 +64,6 @@ static void usage(const char *name)
 		name, name);
 }
 
-void read_member(struct buffer *buff, void *dst, size_t size)
-{
-	uint8_t *src = buffer_get(buff);
-
-	switch (size) {
-	case 1:
-		*(uint8_t *)dst = read_le8(src);
-		break;
-	case 2:
-		*(uint16_t *)dst = read_le16(src);
-		break;
-	case 4:
-		*(uint32_t *)dst = read_le32(src);
-		break;
-	case 8:
-		*(uint64_t *)dst = read_le64(src);
-		break;
-	default:
-		memcpy(dst, src, size);
-	}
-
-	buffer_seek(buff, size);
-}
-
 static int get_fpt_buff(struct buffer *input_buff, struct buffer *fpt_buff)
 {
 	/*

util/cbfstool/cse_fpt.h

@@ -7,12 +7,11 @@
 #include <commonlib/region.h>
 
 #include "common.h"
+#include "cse_helpers.h"
 
 #define FPT_MARKER			"$FPT"
 #define FPT_ENTRY_VERSION		0x10
 
-#define READ_MEMBER(_buff, _x)		read_member(_buff, &(_x), sizeof(_x))
-
 enum fpt_hdr_version {
 	FPT_HDR_VERSION_20 = 0x20,
 	FPT_HDR_VERSION_21 = 0x21,
@@ -32,6 +31,4 @@ struct fpt_hdr_ops {
 extern const struct fpt_hdr_ops fpt_hdr_20_ops;
 extern const struct fpt_hdr_ops fpt_hdr_21_ops;
 
-void read_member(struct buffer *buff, void *dst, size_t size);
-
 #endif /* __CBFSTOOL_CSE_FPT_H__ */

util/cbfstool/cse_helpers.c

@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Helper functions for cse_serger and cse_fpt */
+
+#include <commonlib/endian.h>
+
+#include "cse_helpers.h"
+
+void write_member(struct buffer *buff, void *src, size_t size)
+{
+	void *dst = buffer_get(buff);
+
+	switch (size) {
+	case 1:
+		write_le8(dst, *(uint8_t *)src);
+		break;
+	case 2:
+		write_le16(dst, *(uint16_t *)src);
+		break;
+	case 4:
+		write_le32(dst, *(uint32_t *)src);
+		break;
+	case 8:
+		write_le64(dst, *(uint64_t *)src);
+		break;
+	default:
+		memcpy(dst, src, size);
+		break;
+	}
+
+	buffer_seek(buff, size);
+}
+
+void read_member(struct buffer *buff, void *dst, size_t size)
+{
+	const void *src = buffer_get(buff);
+
+	switch (size) {
+	case 1:
+		*(uint8_t *)dst = read_le8(src);
+		break;
+	case 2:
+		*(uint16_t *)dst = read_le16(src);
+		break;
+	case 4:
+		*(uint32_t *)dst = read_le32(src);
+		break;
+	case 8:
+		*(uint64_t *)dst = read_le64(src);
+		break;
+	default:
+		memcpy(dst, src, size);
+		break;
+	}
+
+	buffer_seek(buff, size);
+}

util/cbfstool/cse_helpers.h

@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <stddef.h>
+
+#include "common.h"
+
+#define READ_MEMBER(_buff, _x)		read_member(_buff, &(_x), sizeof(_x))
+#define WRITE_MEMBER(_buff, _x)		write_member(_buff, &(_x), sizeof(_x))
+
+/* Write data from `src` of length `size` to buffer in little-endian format and seek the buffer
+   forward by `size` bytes. */
+void write_member(struct buffer *buff, void *src, size_t size);
+
+/* Read data from buffer in little-endian format of length `size` to `dst` and seek the buffer
+   forward by `size` bytes. */
+void read_member(struct buffer *buff, void *dst, size_t size);

util/cbfstool/cse_serger.c

@@ -165,56 +165,6 @@ static int subpart_get_type_from_name(const char *name)
 	return -1;
 }
 
-void write_member(struct buffer *buff, void *src, size_t size)
-{
-	void *dst = buffer_get(buff);
-
-	switch (size) {
-	case 1:
-		write_le8(dst, *(uint8_t *)src);
-		break;
-	case 2:
-		write_le16(dst, *(uint16_t *)src);
-		break;
-	case 4:
-		write_le32(dst, *(uint32_t *)src);
-		break;
-	case 8:
-		write_le64(dst, *(uint64_t *)src);
-		break;
-	default:
-		memcpy(dst, src, size);
-		break;
-	}
-
-	buffer_seek(buff, size);
-}
-
-void read_member(struct buffer *buff, void *dst, size_t size)
-{
-	const void *src = buffer_get(buff);
-
-	switch (size) {
-	case 1:
-		*(uint8_t *)dst = read_le8(src);
-		break;
-	case 2:
-		*(uint16_t *)dst = read_le16(src);
-		break;
-	case 4:
-		*(uint32_t *)dst = read_le32(src);
-		break;
-	case 8:
-		*(uint64_t *)dst = read_le64(src);
-		break;
-	default:
-		memcpy(dst, src, size);
-		break;
-	}
-
-	buffer_seek(buff, size);
-}
-
 static const struct bpdt_ops *get_bpdt_ops(const struct buffer *buff)
 {
 	assert(buff || params.version_str);

util/cbfstool/cse_serger.h

@@ -7,14 +7,12 @@
 #include <commonlib/region.h>
 
 #include "common.h"
+#include "cse_helpers.h"
 
 #define BPDT_SIGNATURE			(0x000055AA)
 
 #define BUFF_SIZE_ALIGN			(4 * KiB)
 
-#define READ_MEMBER(_buff, _x)		read_member(_buff, &(_x), sizeof(_x))
-#define WRITE_MEMBER(_buff, _x)		write_member(_buff, &(_x), sizeof(_x))
-
 enum bpdt_version {
 	BPDT_VERSION_1_6 = 1,
 	BPDT_VERSION_1_7 = 2,
@@ -89,7 +87,4 @@ extern const struct subpart_hdr_ops subpart_hdr_2_ops;
 
 extern const struct subpart_entry_ops subpart_entry_1_ops;
 
-void read_member(struct buffer *buff, void *dst, size_t size);
-void write_member(struct buffer *buff, void *src, size_t size);
-
 #endif /* __CBFSTOOL_CSE_SERGER_H__ */