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Emit the LC_BUILD_VERSION load command when creating a mach object. #13

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Emit the LC_BUILD_VERSION load command when creating a mach object. #13

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23 changes: 23 additions & 0 deletions asm/nasm.c
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Original file line number Diff line number Diff line change
Expand Up @@ -167,6 +167,10 @@ static char *quote_for_pmake(const char *str);
static char *quote_for_wmake(const char *str);
static char *(*quote_for_make)(const char *) = quote_for_pmake;

#if defined(OF_MACHO) || defined(OF_MACHO64)
extern bool macho_set_min_os(const char *str);
#endif

/*
* Execution limits that can be set via a command-line option or %pragma
*/
Expand Down Expand Up @@ -1338,6 +1342,23 @@ static bool process_arg(char *p, char *q, int pass)
case OPT_REPRODUCIBLE:
reproducible = true;
break;
case OPT_MACHO_MIN_OS:
if (pass == 2) {
if (strstr(ofmt->shortname, "macho") != ofmt->shortname) {
nasm_error(
ERR_WARNING | WARN_OTHER | ERR_USAGE,
"macho-min-os is only valid for macho format, current: %s",
ofmt->shortname);
break;
}
#if defined(OF_MACHO) || defined(OF_MACHO64)
if (!macho_set_min_os(param)) {
nasm_fatalf(ERR_USAGE, "failed to set minimum os for mach-o '%s'",
param);
}
#endif
}
break;
case OPT_HELP:
help(stdout);
exit(0);
Expand Down Expand Up @@ -2297,6 +2318,8 @@ static void help(FILE *out)
"\n"
" --reproducible attempt to produce run-to-run identical output\n"
"\n"
" --macho-min-os minos minimum os version for mach-o format(example: macos-11.0)\n"
"\n"
" -w+x enable warning x (also -Wx)\n"
" -w-x disable warning x (also -Wno-x)\n"
" -w[+-]error promote all warnings to errors (also -Werror)\n"
Expand Down
15 changes: 15 additions & 0 deletions output/macho.h
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Original file line number Diff line number Diff line change
Expand Up @@ -60,6 +60,7 @@
#define LC_SEGMENT 0x1
#define LC_SEGMENT_64 0x19
#define LC_SYMTAB 0x2
#define LC_BUILD_VERSION 0x32

/* Symbol type bits */
#define N_STAB 0xe0
Expand Down Expand Up @@ -144,6 +145,20 @@
#define R_ABS 0
#define R_SCATTERED 0x80000000

/* Known values for the platform field in LC_BUILD_VERSION */
#define PLATFORM_MACOS 1
#define PLATFORM_IOS 2
#define PLATFORM_TVOS 3
#define PLATFORM_WATCHOS 4
#define PLATFORM_BRIDGEOS 5
#define PLATFORM_MACCATALYST 6
#define PLATFORM_IOSSIMULATOR 7
#define PLATFORM_TVOSSIMULATOR 8
#define PLATFORM_WATCHOSSIMULATOR 9
#define PLATFORM_DRIVERKIT 10

#define PLATFORM_INVALID 0

/* VM permission constants */
#define VM_PROT_NONE 0x00
#define VM_PROT_READ 0x01
Expand Down
117 changes: 117 additions & 0 deletions output/outmacho.c
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Original file line number Diff line number Diff line change
Expand Up @@ -64,6 +64,7 @@
#define MACHO_SYMCMD_SIZE 24
#define MACHO_NLIST_SIZE 12
#define MACHO_RELINFO_SIZE 8
#define MACHO_BUILDVERSION_SIZE 24

#define MACHO_HEADER64_SIZE 32
#define MACHO_SEGCMD64_SIZE 72
Expand Down Expand Up @@ -215,6 +216,15 @@ static uint64_t seg_vmsize = 0;
static uint32_t seg_nsects = 0;
static uint64_t rel_padcnt = 0;

/* build_version_platform information
PLATFORM_INVALID implies that build_version_platform won't emitted. */
static uint32_t build_version_platform = PLATFORM_INVALID;
/* X.Y.Z is encoded in nibbles xxxx.yy.zz */
static uint32_t build_version_minos = 0;

/* used in nasm.c */
bool macho_set_min_os(const char *str);

/*
* Functions for handling fixed-length zero-padded string
* fields, that may or may not be null-terminated.
Expand Down Expand Up @@ -744,6 +754,7 @@ static const struct macho_known_section {
{ ".data", "__DATA", "__data", S_REGULAR },
{ ".rodata", "__DATA", "__const", S_REGULAR },
{ ".bss", "__DATA", "__bss", S_ZEROFILL },
{".llvmasm", "__LLVM", "__asm", S_REGULAR },
{ ".debug_abbrev", "__DWARF", "__debug_abbrev", S_ATTR_DEBUG },
{ ".debug_info", "__DWARF", "__debug_info", S_ATTR_DEBUG },
{ ".debug_line", "__DWARF", "__debug_line", S_ATTR_DEBUG },
Expand Down Expand Up @@ -1263,6 +1274,12 @@ static void macho_calculate_sizes (void)
}
}

/* for build_version_command */
if (build_version_platform != PLATFORM_INVALID) {
++head_ncmds;
head_sizeofcmds = MACHO_BUILDVERSION_SIZE;
}

/* calculate size of all headers, load commands and sections to
** get a pointer to the start of all the raw data */
if (seg_nsects > 0) {
Expand Down Expand Up @@ -1647,6 +1664,16 @@ static void macho_write (void)

offset = fmt.header_size + head_sizeofcmds;

if (build_version_platform != PLATFORM_INVALID) {
/* emit build_version_command */
fwriteint32_t(LC_BUILD_VERSION, ofile);
fwriteint32_t(MACHO_BUILDVERSION_SIZE, ofile);
fwriteint32_t(build_version_platform, ofile);
fwriteint32_t(build_version_minos, ofile);
fwriteint32_t(0 /* sdk */, ofile);
fwriteint32_t(0 /* ntools */, ofile);
}

/* emit the segment load command */
if (seg_nsects > 0)
offset = macho_write_segment (offset);
Expand Down Expand Up @@ -1687,9 +1714,20 @@ static void macho_cleanup(void)
struct section *s;
struct reloc *r;
struct symbol *sym;
int bits;

dfmt->cleanup();

/* create a dummy __asm section with a single zero byte.
* this is a workaround for making binaries compatible with
* bitcode enabled, which is required for watchOS and tvOS */
macho_section(".llvmasm", &bits);
s = get_section_by_name("__LLVM", "__asm");
if (s != NULL) {
saa_write8(s->data, 0);
s->size += 1;
}

/* Sort all symbols. */
macho_layout_symbols (&nsyms, &strslen);

Expand Down Expand Up @@ -2376,6 +2414,85 @@ static const struct dfmt macho64_df_dwarf = {
static const struct dfmt * const macho64_df_arr[2] =
{ &macho64_df_dwarf, NULL };

bool macho_set_min_os(const char *str) {
nasm_assert(str != NULL);

const char *platform_ver = nasm_strdup(str);
const char *environment = "";
char *sep = strchr(platform_ver, '-');
if (sep != NULL) {
sep[0] = '\0';
environment = sep + 1;
}

const char *version = platform_ver;
while (*version) {
if (*version >= '0' && *version <= '9') {
break;
}
++version;
}
if (*version == '\0') {
nasm_free((char *)platform_ver);
return false;
}

/* Mimic clang's target triple */
int platform = PLATFORM_INVALID;
if (strstr(platform_ver, "macos") == platform_ver) {
platform = PLATFORM_MACOS;
} else if ((strstr(platform_ver, "ios") == platform_ver)) {
if (environment[0] == '\0') {
platform = PLATFORM_IOS;
} else if ((strstr(environment, "simulator") == environment)) {
platform = PLATFORM_IOSSIMULATOR;
} else if ((strstr(environment, "catalyst") == environment)) {
platform = PLATFORM_MACCATALYST;
} else {
nasm_free((char *)platform_ver);
return false;
}
} else if ((strstr(platform_ver, "tvos") == platform_ver)) {
if (environment[0] == '\0') {
platform = PLATFORM_TVOS;
} else if ((strstr(environment, "simulator") == environment)) {
platform = PLATFORM_TVOSSIMULATOR;
} else {
nasm_free((char *)platform_ver);
return false;
}
} else if (xstrncmp("watchos", platform_ver) == 0) {
if (environment[0] == '\0') {
platform = PLATFORM_WATCHOS;
} else if ((strstr(environment, "simulator") == environment)) {
platform = PLATFORM_WATCHOSSIMULATOR;
} else {
nasm_free((char *)platform_ver);
return false;
}
} else if (xstrncmp("bridgeos", platform_ver) == 0) {
platform = PLATFORM_BRIDGEOS;
} else {
nasm_free((char *)platform_ver);
return false;
}

unsigned short major = 0, minor = 0, subminor = 0;
int count = sscanf(version, "%hu.%hu.%hu", &major, &minor, &subminor);
/* at least major and minor must be given */
if (count < 2) {
nasm_free((char *)platform_ver);
return false;
}

build_version_platform = platform;
build_version_minos =
((major & 0xffff) << 16) | ((minor & 0xff) << 8) | (subminor & 0xff);

nasm_free((char *)platform_ver);
return true;
}

const struct ofmt of_macho64 = {
"Mach-O x86-64 (Mach, including MacOS X and variants)",
"macho64",
Expand Down