meson: use 0|1 for SD_BOOT

We converted to not using #ifdef for most of our defines because the syntax is
nicer and we are protected against typos and can set -Werror=undef. Let's do
the same for SD_BOOT. The define is nicely hidden in build.h for normal builds,
and for EFI builds we were already setting SD_BOOT on the commandline.

meson.build

@@ -55,6 +55,9 @@ fuzzer_build = want_ossfuzz or want_libfuzzer
 # limits).
 conf.set10('FUZZ_USE_SIZE_LIMIT', fuzzer_build)
 
+# We'll set this to '1' for EFI builds in a different place.
+conf.set10('SD_BOOT', false)
+
 # Create a title-less summary section early, so it ends up first in the output.
 # More items are added later after they have been detected.
 summary({'build mode' : get_option('mode')})

src/boot/efi/efi-string.c

@@ -5,7 +5,7 @@
 
 #include "efi-string.h"
 
-#ifdef SD_BOOT
+#if SD_BOOT
 #  include "util.h"
 #else
 #  include <stdlib.h>
@@ -378,7 +378,7 @@ bool efi_fnmatch(const char16_t *pattern, const char16_t *haystack) {
 DEFINE_PARSE_NUMBER(char, parse_number8);
 DEFINE_PARSE_NUMBER(char16_t, parse_number16);
 
-#ifdef SD_BOOT
+#if SD_BOOT
 /* To provide the actual implementation for these we need to remove the redirection to the builtins. */
 #  undef memcmp
 #  undef memcpy
@@ -414,7 +414,7 @@ _used_ _weak_ void *memcpy(void * restrict dest, const void * restrict src, size
         if (!dest || !src || n == 0)
                 return dest;
 
-#ifdef SD_BOOT
+#if SD_BOOT
         /* The firmware-provided memcpy is likely optimized, so use that. The function is guaranteed to be
          * available by the UEFI spec. We still make it depend on the boot services pointer being set just in
          * case the compiler emits a call before it is available. */
@@ -441,7 +441,7 @@ _used_ _weak_ void *memset(void *p, int c, size_t n) {
         if (!p || n == 0)
                 return p;
 
-#ifdef SD_BOOT
+#if SD_BOOT
         /* See comment in efi_memcpy. Note that the signature has c and n swapped! */
         if (_likely_(BS)) {
                 BS->SetMem(p, n, c);

src/boot/efi/efi-string.h

@@ -109,7 +109,7 @@ bool efi_fnmatch(const char16_t *pattern, const char16_t *haystack);
 bool parse_number8(const char *s, uint64_t *ret_u, const char **ret_tail);
 bool parse_number16(const char16_t *s, uint64_t *ret_u, const char16_t **ret_tail);
 
-#ifdef SD_BOOT
+#if SD_BOOT
 /* The compiler normally has knowledge about standard functions such as memcmp, but this is not the case when
  * compiling with -ffreestanding. By referring to builtins, the compiler can check arguments and do
  * optimizations again. Note that we still need to provide implementations as the compiler is free to not

src/boot/efi/meson.build

@@ -175,7 +175,7 @@ efi_config_h = configure_file(
 
 efi_cflags = [
         '-DGNU_EFI_USE_MS_ABI',
-        '-DSD_BOOT',
+        '-DSD_BOOT=1',
         '-ffreestanding',
         '-fshort-wchar',
         '-fvisibility=hidden',

src/fundamental/macro-fundamental.h

@@ -1,7 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
-#ifndef SD_BOOT
+#if !SD_BOOT
 #  include <assert.h>
 #endif
 
@@ -67,7 +67,7 @@
 #define XCONCATENATE(x, y) x ## y
 #define CONCATENATE(x, y) XCONCATENATE(x, y)
 
-#ifdef SD_BOOT
+#if SD_BOOT
         _noreturn_ void efi_assert(const char *expr, const char *file, unsigned line, const char *function);
 
         #ifdef NDEBUG
@@ -334,7 +334,7 @@ static inline size_t ALIGN_TO(size_t l, size_t ali) {
 #define ALIGN2_PTR(p) ((void*) ALIGN2((uintptr_t) p))
 #define ALIGN4_PTR(p) ((void*) ALIGN4((uintptr_t) p))
 #define ALIGN8_PTR(p) ((void*) ALIGN8((uintptr_t) p))
-#ifndef SD_BOOT
+#if !SD_BOOT
 /* libefi also provides ALIGN, and we do not use them in sd-boot explicitly. */
 #define ALIGN(l)  ALIGN_TO(l, sizeof(void*))
 #define ALIGN_PTR(p) ((void*) ALIGN((uintptr_t) (p)))

src/fundamental/memory-util-fundamental.h

@@ -3,7 +3,7 @@
 
 #include <stddef.h>
 
-#ifdef SD_BOOT
+#if SD_BOOT
 #  include "efi-string.h"
 #else
 #  include <string.h>
@@ -11,7 +11,7 @@
 
 #include "macro-fundamental.h"
 
-#if !defined(SD_BOOT) && HAVE_EXPLICIT_BZERO
+#if !SD_BOOT && HAVE_EXPLICIT_BZERO
 static inline void *explicit_bzero_safe(void *p, size_t l) {
         if (p && l > 0)
                 explicit_bzero(p, l);

src/fundamental/sha256.c

@@ -22,7 +22,7 @@
    <https://www.gnu.org/licenses/>.  */
 
 #include <stdbool.h>
-#ifdef SD_BOOT
+#if SD_BOOT
 #  include "efi-string.h"
 #else
 #  include <string.h>

src/fundamental/string-util-fundamental.c

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
-#ifndef SD_BOOT
+#if !SD_BOOT
 #  include <ctype.h>
 #endif
 
@@ -20,7 +20,7 @@ sd_char *startswith(const sd_char *s, const sd_char *prefix) {
         return (sd_char*) s + l;
 }
 
-#ifndef SD_BOOT
+#if !SD_BOOT
 sd_char *startswith_no_case(const sd_char *s, const sd_char *prefix) {
         size_t l;
 

src/fundamental/string-util-fundamental.h

@@ -1,7 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
-#ifdef SD_BOOT
+#if SD_BOOT
 #  include <efi.h>
 #  include <efilib.h>
 #  include "efi-string.h"
@@ -11,7 +11,7 @@
 
 #include "macro-fundamental.h"
 
-#ifdef SD_BOOT
+#if SD_BOOT
 #  define strlen strlen16
 #  define strcmp strcmp16
 #  define strncmp strncmp16
@@ -59,7 +59,7 @@ static inline size_t strlen_ptr(const sd_char *s) {
 }
 
 sd_char *startswith(const sd_char *s, const sd_char *prefix) _pure_;
-#ifndef SD_BOOT
+#if !SD_BOOT
 sd_char *startswith_no_case(const sd_char *s, const sd_char *prefix) _pure_;
 #endif
 sd_char *endswith(const sd_char *s, const sd_char *postfix) _pure_;