scripts/sorttable: Convert Elf_Ehdr to union

In order to remove the double #include of sorttable.h for 64 and 32 bit
to create duplicate functions for both, replace the Elf_Ehdr macro with a
union that defines both Elf64_Ehdr and Elf32_Ehdr, with field e64 for the
64bit version, and e32 for the 32bit version.

Then a macro etype can be used instead to get to the proper value.

This will eventually be replaced with just single functions that can
handle both 32bit and 64bit ELF parsing.

Cc: bpf <bpf@vger.kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Zheng Yejian <zhengyejian1@huawei.com>
Cc: Martin  Kelly <martin.kelly@crowdstrike.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/20250105162345.148224465@goodmis.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

1 files changed, 20 insertions, 16 deletions

diff --git a/scripts/sorttable.c b/scripts/sorttable.c
index 3e2c17e91485..67cbbfc8214d 100644
--- a/scripts/sorttable.c
+++ b/scripts/sorttable.c
@@ -64,6 +64,11 @@
 #define EM_LOONGARCH	258
 #endif
 
+typedef union {
+	Elf32_Ehdr	e32;
+	Elf64_Ehdr	e64;
+} Elf_Ehdr;
+
 static uint32_t (*r)(const uint32_t *);
 static uint16_t (*r2)(const uint16_t *);
 static uint64_t (*r8)(const uint64_t *);
@@ -266,10 +271,10 @@ static void sort_relative_table_with_data(char *extab_image, int image_size)
 static int do_file(char const *const fname, void *addr)
 {
 	int rc = -1;
-	Elf32_Ehdr *ehdr = addr;
+	Elf_Ehdr *ehdr = addr;
 	table_sort_t custom_sort = NULL;
 
-	switch (ehdr->e_ident[EI_DATA]) {
+	switch (ehdr->e32.e_ident[EI_DATA]) {
 	case ELFDATA2LSB:
 		r	= rle;
 		r2	= r2le;
@@ -284,18 +289,18 @@ static int do_file(char const *const fname, void *addr)
 		break;
 	default:
 		fprintf(stderr, "unrecognized ELF data encoding %d: %s\n",
-			ehdr->e_ident[EI_DATA], fname);
+			ehdr->e32.e_ident[EI_DATA], fname);
 		return -1;
 	}
 
-	if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 ||
-	    (r2(&ehdr->e_type) != ET_EXEC && r2(&ehdr->e_type) != ET_DYN) ||
-	    ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
+	if (memcmp(ELFMAG, ehdr->e32.e_ident, SELFMAG) != 0 ||
+	    (r2(&ehdr->e32.e_type) != ET_EXEC && r2(&ehdr->e32.e_type) != ET_DYN) ||
+	    ehdr->e32.e_ident[EI_VERSION] != EV_CURRENT) {
 		fprintf(stderr, "unrecognized ET_EXEC/ET_DYN file %s\n", fname);
 		return -1;
 	}
 
-	switch (r2(&ehdr->e_machine)) {
+	switch (r2(&ehdr->e32.e_machine)) {
 	case EM_386:
 	case EM_AARCH64:
 	case EM_LOONGARCH:
@@ -318,14 +323,14 @@ static int do_file(char const *const fname, void *addr)
 		break;
 	default:
 		fprintf(stderr, "unrecognized e_machine %d %s\n",
-			r2(&ehdr->e_machine), fname);
+			r2(&ehdr->e32.e_machine), fname);
 		return -1;
 	}
 
-	switch (ehdr->e_ident[EI_CLASS]) {
+	switch (ehdr->e32.e_ident[EI_CLASS]) {
 	case ELFCLASS32:
-		if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr) ||
-		    r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) {
+		if (r2(&ehdr->e32.e_ehsize) != sizeof(Elf32_Ehdr) ||
+		    r2(&ehdr->e32.e_shentsize) != sizeof(Elf32_Shdr)) {
 			fprintf(stderr,
 				"unrecognized ET_EXEC/ET_DYN file: %s\n", fname);
 			break;
@@ -334,20 +339,19 @@ static int do_file(char const *const fname, void *addr)
 		break;
 	case ELFCLASS64:
 		{
-		Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr;
-		if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr) ||
-		    r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) {
+		if (r2(&ehdr->e64.e_ehsize) != sizeof(Elf64_Ehdr) ||
+		    r2(&ehdr->e64.e_shentsize) != sizeof(Elf64_Shdr)) {
 			fprintf(stderr,
 				"unrecognized ET_EXEC/ET_DYN file: %s\n",
 				fname);
 			break;
 		}
-		rc = do_sort_64(ghdr, fname, custom_sort);
+		rc = do_sort_64(ehdr, fname, custom_sort);
 		}
 		break;
 	default:
 		fprintf(stderr, "unrecognized ELF class %d %s\n",
-			ehdr->e_ident[EI_CLASS], fname);
+			ehdr->e32.e_ident[EI_CLASS], fname);
 		break;
 	}