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tinycc/tccmacho.c
grischka 56481d554f bored... 
/* Use "-g" as alias for "-g1". Use "-g0" to disable debug */

So not using -g is now the alias for -g0 ?!?

This reverts commit 8759b2581d.
This reverts commit 3ce7bc6efc.
This reverts commit 5fb582ab7f.
This reverts commit aea68dbb40.
This reverts commit fa9c31c3db.
This reverts commit b3bebdb20a.
This reverts commit ecf8e5a00e.
This reverts commit fe6b5c08dc.
This reverts commit e2e5377e7b.
This reverts commit 1cd7998905.
2022-05-09 22:19:15 +02:00

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/*
* Mach-O file handling for TCC
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "tcc.h"
/* In order to make life easy for us we are generating Mach-O files which
don't make use of some modern features, but which aren't entirely classic
either in that they do use some modern features. We're also only
generating 64bit Mach-O files, and only native endian at that.
In particular we're generating executables that don't make use of
DYLD_INFO for dynamic linking info, as that requires us building a
trie of exported names. We're simply using classic symbol tables which
are still supported by modern dyld.
But we do use LC_MAIN, which is a "modern" feature in order to not have
to setup our own crt code. We're not using lazy linking, so even function
calls are resolved at startup. */
#define DEBUG_MACHO 0
#define dprintf if (DEBUG_MACHO) printf
struct fat_header {
uint32_t magic; /* FAT_MAGIC or FAT_MAGIC_64 */
uint32_t nfat_arch; /* number of structs that follow */
};
struct fat_arch {
int cputype; /* cpu specifier (int) */
int cpusubtype; /* machine specifier (int) */
uint32_t offset; /* file offset to this object file */
uint32_t size; /* size of this object file */
uint32_t align; /* alignment as a power of 2 */
};
#define FAT_MAGIC 0xcafebabe
#define FAT_CIGAM 0xbebafeca
#define FAT_MAGIC_64 0xcafebabf
#define FAT_CIGAM_64 0xbfbafeca
struct mach_header {
uint32_t magic; /* mach magic number identifier */
int cputype; /* cpu specifier */
int cpusubtype; /* machine specifier */
uint32_t filetype; /* type of file */
uint32_t ncmds; /* number of load commands */
uint32_t sizeofcmds; /* the size of all the load commands */
uint32_t flags; /* flags */
};
struct mach_header_64 {
struct mach_header mh;
uint32_t reserved; /* reserved, pad to 64bit */
};
/* Constant for the magic field of the mach_header (32-bit architectures) */
#define MH_MAGIC 0xfeedface /* the mach magic number */
#define MH_CIGAM 0xcefaedfe /* NXSwapInt(MH_MAGIC) */
#define MH_MAGIC_64 0xfeedfacf /* the 64-bit mach magic number */
#define MH_CIGAM_64 0xcffaedfe /* NXSwapInt(MH_MAGIC_64) */
struct load_command {
uint32_t cmd; /* type of load command */
uint32_t cmdsize; /* total size of command in bytes */
};
#define LC_REQ_DYLD 0x80000000
#define LC_SYMTAB 0x2
#define LC_DYSYMTAB 0xb
#define LC_LOAD_DYLIB 0xc
#define LC_ID_DYLIB 0xd
#define LC_LOAD_DYLINKER 0xe
#define LC_SEGMENT_64 0x19
#define LC_REEXPORT_DYLIB (0x1f | LC_REQ_DYLD)
#define LC_MAIN (0x28|LC_REQ_DYLD)
typedef int vm_prot_t;
struct segment_command_64 { /* for 64-bit architectures */
uint32_t cmd; /* LC_SEGMENT_64 */
uint32_t cmdsize; /* includes sizeof section_64 structs */
char segname[16]; /* segment name */
uint64_t vmaddr; /* memory address of this segment */
uint64_t vmsize; /* memory size of this segment */
uint64_t fileoff; /* file offset of this segment */
uint64_t filesize; /* amount to map from the file */
vm_prot_t maxprot; /* maximum VM protection */
vm_prot_t initprot; /* initial VM protection */
uint32_t nsects; /* number of sections in segment */
uint32_t flags; /* flags */
};
struct section_64 { /* for 64-bit architectures */
char sectname[16]; /* name of this section */
char segname[16]; /* segment this section goes in */
uint64_t addr; /* memory address of this section */
uint64_t size; /* size in bytes of this section */
uint32_t offset; /* file offset of this section */
uint32_t align; /* section alignment (power of 2) */
uint32_t reloff; /* file offset of relocation entries */
uint32_t nreloc; /* number of relocation entries */
uint32_t flags; /* flags (section type and attributes)*/
uint32_t reserved1; /* reserved (for offset or index) */
uint32_t reserved2; /* reserved (for count or sizeof) */
uint32_t reserved3; /* reserved */
};
#define S_REGULAR 0x0
#define S_ZEROFILL 0x1
#define S_NON_LAZY_SYMBOL_POINTERS 0x6
#define S_MOD_INIT_FUNC_POINTERS 0x9
#define S_MOD_TERM_FUNC_POINTERS 0xa
#define S_ATTR_PURE_INSTRUCTIONS 0x80000000
#define S_ATTR_SOME_INSTRUCTIONS 0x00000400
typedef uint32_t lc_str;
struct dylib_command {
uint32_t cmd; /* LC_ID_DYLIB, LC_LOAD_{,WEAK_}DYLIB,
LC_REEXPORT_DYLIB */
uint32_t cmdsize; /* includes pathname string */
lc_str name; /* library's path name */
uint32_t timestamp; /* library's build time stamp */
uint32_t current_version; /* library's current version number */
uint32_t compatibility_version; /* library's compatibility vers number*/
};
struct dylinker_command {
uint32_t cmd; /* LC_ID_DYLINKER, LC_LOAD_DYLINKER or
LC_DYLD_ENVIRONMENT */
uint32_t cmdsize; /* includes pathname string */
lc_str name; /* dynamic linker's path name */
};
struct symtab_command {
uint32_t cmd; /* LC_SYMTAB */
uint32_t cmdsize; /* sizeof(struct symtab_command) */
uint32_t symoff; /* symbol table offset */
uint32_t nsyms; /* number of symbol table entries */
uint32_t stroff; /* string table offset */
uint32_t strsize; /* string table size in bytes */
};
struct dysymtab_command {
uint32_t cmd; /* LC_DYSYMTAB */
uint32_t cmdsize; /* sizeof(struct dysymtab_command) */
uint32_t ilocalsym; /* index to local symbols */
uint32_t nlocalsym; /* number of local symbols */
uint32_t iextdefsym;/* index to externally defined symbols */
uint32_t nextdefsym;/* number of externally defined symbols */
uint32_t iundefsym; /* index to undefined symbols */
uint32_t nundefsym; /* number of undefined symbols */
uint32_t tocoff; /* file offset to table of contents */
uint32_t ntoc; /* number of entries in table of contents */
uint32_t modtaboff; /* file offset to module table */
uint32_t nmodtab; /* number of module table entries */
uint32_t extrefsymoff; /* offset to referenced symbol table */
uint32_t nextrefsyms; /* number of referenced symbol table entries */
uint32_t indirectsymoff;/* file offset to the indirect symbol table */
uint32_t nindirectsyms; /* number of indirect symbol table entries */
uint32_t extreloff; /* offset to external relocation entries */
uint32_t nextrel; /* number of external relocation entries */
uint32_t locreloff; /* offset to local relocation entries */
uint32_t nlocrel; /* number of local relocation entries */
};
#define INDIRECT_SYMBOL_LOCAL 0x80000000
struct entry_point_command {
uint32_t cmd; /* LC_MAIN only used in MH_EXECUTE filetypes */
uint32_t cmdsize; /* 24 */
uint64_t entryoff; /* file (__TEXT) offset of main() */
uint64_t stacksize;/* if not zero, initial stack size */
};
enum skind {
sk_unknown = 0,
sk_discard,
sk_text,
sk_stubs,
sk_ro_data,
sk_uw_info,
sk_nl_ptr, // non-lazy pointers, aka GOT
sk_la_ptr, // lazy pointers
sk_init,
sk_fini,
sk_rw_data,
sk_bss,
sk_linkedit,
sk_last
};
struct nlist_64 {
uint32_t n_strx; /* index into the string table */
uint8_t n_type; /* type flag, see below */
uint8_t n_sect; /* section number or NO_SECT */
uint16_t n_desc; /* see <mach-o/stab.h> */
uint64_t n_value; /* value of this symbol (or stab offset) */
};
#define N_UNDF 0x0
#define N_ABS 0x2
#define N_EXT 0x1
#define N_SECT 0xe
#define N_WEAK_REF 0x0040
#define N_WEAK_DEF 0x0080
struct macho {
struct mach_header_64 mh;
int seg2lc[4], nseg;
struct load_command **lc;
struct entry_point_command *ep;
int nlc;
struct {
Section *s;
int machosect;
} sk_to_sect[sk_last];
int *elfsectomacho;
int *e2msym;
Section *symtab, *strtab, *wdata, *indirsyms, *stubs;
int stubsym;
uint32_t ilocal, iextdef, iundef;
};
#define SHT_LINKEDIT (SHT_LOOS + 42)
#define SHN_FROMDLL (SHN_LOOS + 2) /* Symbol is undefined, comes from a DLL */
static void * add_lc(struct macho *mo, uint32_t cmd, uint32_t cmdsize)
{
struct load_command *lc = tcc_mallocz(cmdsize);
lc->cmd = cmd;
lc->cmdsize = cmdsize;
mo->lc = tcc_realloc(mo->lc, sizeof(mo->lc[0]) * (mo->nlc + 1));
mo->lc[mo->nlc++] = lc;
return lc;
}
static struct segment_command_64 * add_segment(struct macho *mo, const char *name)
{
struct segment_command_64 *sc = add_lc(mo, LC_SEGMENT_64, sizeof(*sc));
strncpy(sc->segname, name, 16);
mo->seg2lc[mo->nseg++] = mo->nlc - 1;
return sc;
}
static struct segment_command_64 * get_segment(struct macho *mo, int i)
{
return (struct segment_command_64 *) (mo->lc[mo->seg2lc[i]]);
}
static int add_section(struct macho *mo, struct segment_command_64 **_seg, const char *name)
{
struct segment_command_64 *seg = *_seg;
int ret = seg->nsects;
struct section_64 *sec;
seg->nsects++;
seg->cmdsize += sizeof(*sec);
seg = tcc_realloc(seg, sizeof(*seg) + seg->nsects * sizeof(*sec));
sec = (struct section_64*)((char*)seg + sizeof(*seg)) + ret;
memset(sec, 0, sizeof(*sec));
strncpy(sec->sectname, name, 16);
strncpy(sec->segname, seg->segname, 16);
*_seg = seg;
return ret;
}
static struct section_64 *get_section(struct segment_command_64 *seg, int i)
{
return (struct section_64*)((char*)seg + sizeof(*seg)) + i;
}
static void * add_dylib(struct macho *mo, char *name)
{
struct dylib_command *lc;
int sz = (sizeof(*lc) + strlen(name) + 1 + 7) & -8;
lc = add_lc(mo, LC_LOAD_DYLIB, sz);
lc->name = sizeof(*lc);
strcpy((char*)lc + lc->name, name);
lc->timestamp = 2;
lc->current_version = 1 << 16;
lc->compatibility_version = 1 << 16;
return lc;
}
static void check_relocs(TCCState *s1, struct macho *mo)
{
Section *s;
ElfW_Rel *rel;
ElfW(Sym) *sym;
int i, type, gotplt_entry, sym_index, for_code;
struct sym_attr *attr;
s1->got = new_section(s1, ".got", SHT_PROGBITS, SHF_ALLOC | SHF_WRITE);
mo->indirsyms = new_section(s1, "LEINDIR", SHT_LINKEDIT, SHF_ALLOC | SHF_WRITE);
for (i = 1; i < s1->nb_sections; i++) {
s = s1->sections[i];
if (s->sh_type != SHT_RELX)
continue;
for_each_elem(s, 0, rel, ElfW_Rel) {
type = ELFW(R_TYPE)(rel->r_info);
gotplt_entry = gotplt_entry_type(type);
for_code = code_reloc(type);
/* We generate a non-lazy pointer for used undefined symbols
and for defined symbols that must have a place for their
address due to codegen (i.e. a reloc requiring a got slot). */
sym_index = ELFW(R_SYM)(rel->r_info);
sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
if (sym->st_shndx == SHN_UNDEF
|| gotplt_entry == ALWAYS_GOTPLT_ENTRY) {
attr = get_sym_attr(s1, sym_index, 1);
if (!attr->dyn_index) {
uint32_t *pi = section_ptr_add(mo->indirsyms, sizeof(*pi));
attr->got_offset = s1->got->data_offset;
attr->plt_offset = -1;
attr->dyn_index = 1; /* used as flag */
section_ptr_add(s1->got, PTR_SIZE);
if (ELFW(ST_BIND)(sym->st_info) == STB_LOCAL) {
if (sym->st_shndx == SHN_UNDEF)
tcc_error("undefined local symbol???");
*pi = INDIRECT_SYMBOL_LOCAL;
/* The pointer slot we generated must point to the
symbol, whose address is only known after layout,
so register a simple relocation for that. */
put_elf_reloc(s1->symtab, s1->got, attr->got_offset,
R_DATA_PTR, sym_index);
} else
*pi = mo->e2msym[sym_index];
}
if (for_code) {
if (attr->plt_offset == -1) {
uint8_t *jmp;
attr->plt_offset = mo->stubs->data_offset;
jmp = section_ptr_add(mo->stubs, 6);
jmp[0] = 0xff; /* jmpq *ofs(%rip) */
jmp[1] = 0x25;
put_elf_reloc(s1->symtab, mo->stubs,
attr->plt_offset + 2,
R_X86_64_GOTPCREL, sym_index);
}
rel->r_info = ELFW(R_INFO)(mo->stubsym, type);
rel->r_addend += attr->plt_offset;
}
}
}
}
}
static int check_symbols(TCCState *s1, struct macho *mo)
{
int sym_index, sym_end;
int ret = 0;
mo->ilocal = mo->iextdef = mo->iundef = -1;
sym_end = symtab_section->data_offset / sizeof(ElfW(Sym));
for (sym_index = 1; sym_index < sym_end; ++sym_index) {
int elf_index = ((struct nlist_64 *)mo->symtab->data + sym_index - 1)->n_value;
ElfW(Sym) *sym = (ElfW(Sym) *)symtab_section->data + elf_index;
const char *name = (char*)symtab_section->link->data + sym->st_name;
unsigned type = ELFW(ST_TYPE)(sym->st_info);
unsigned bind = ELFW(ST_BIND)(sym->st_info);
unsigned vis = ELFW(ST_VISIBILITY)(sym->st_other);
dprintf("%4d (%4d): %09lx %4d %4d %4d %3d %s\n",
sym_index, elf_index, (long)sym->st_value,
type, bind, vis, sym->st_shndx, name);
if (bind == STB_LOCAL) {
if (mo->ilocal == -1)
mo->ilocal = sym_index - 1;
if (mo->iextdef != -1 || mo->iundef != -1)
tcc_error("local syms after global ones");
} else if (sym->st_shndx != SHN_UNDEF) {
if (mo->iextdef == -1)
mo->iextdef = sym_index - 1;
if (mo->iundef != -1)
tcc_error("external defined symbol after undefined");
} else if (sym->st_shndx == SHN_UNDEF) {
if (mo->iundef == -1)
mo->iundef = sym_index - 1;
if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK
|| find_elf_sym(s1->dynsymtab_section, name)) {
/* Mark the symbol as coming from a dylib so that
relocate_syms doesn't complain. Normally bind_exe_dynsyms
would do this check, and place the symbol into dynsym
which is checked by relocate_syms. But Mach-O doesn't use
bind_exe_dynsyms. */
sym->st_shndx = SHN_FROMDLL;
continue;
}
tcc_error_noabort("undefined symbol '%s'", name);
ret = -1;
}
}
return ret;
}
static void convert_symbol(TCCState *s1, struct macho *mo, struct nlist_64 *pn)
{
struct nlist_64 n = *pn;
ElfSym *sym = (ElfW(Sym) *)symtab_section->data + pn->n_value;
const char *name = (char*)symtab_section->link->data + sym->st_name;
switch(ELFW(ST_TYPE)(sym->st_info)) {
case STT_NOTYPE:
case STT_OBJECT:
case STT_FUNC:
case STT_SECTION:
n.n_type = N_SECT;
break;
case STT_FILE:
n.n_type = N_ABS;
break;
default:
tcc_error("unhandled ELF symbol type %d %s",
ELFW(ST_TYPE)(sym->st_info), name);
}
if (sym->st_shndx == SHN_UNDEF)
tcc_error("should have been rewritten to SHN_FROMDLL: %s", name);
else if (sym->st_shndx == SHN_FROMDLL)
n.n_type = N_UNDF, n.n_sect = 0;
else if (sym->st_shndx == SHN_ABS)
n.n_type = N_ABS, n.n_sect = 0;
else if (sym->st_shndx >= SHN_LORESERVE)
tcc_error("unhandled ELF symbol section %d %s", sym->st_shndx, name);
else if (!mo->elfsectomacho[sym->st_shndx])
tcc_error("ELF section %d not mapped into Mach-O for symbol %s",
sym->st_shndx, name);
else
n.n_sect = mo->elfsectomacho[sym->st_shndx];
if (ELFW(ST_BIND)(sym->st_info) == STB_GLOBAL)
n.n_type |= N_EXT;
else if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK)
n.n_desc |= N_WEAK_REF | (n.n_type != N_UNDF ? N_WEAK_DEF : 0);
n.n_strx = pn->n_strx;
n.n_value = sym->st_value;
*pn = n;
}
static void convert_symbols(TCCState *s1, struct macho *mo)
{
struct nlist_64 *pn;
for_each_elem(mo->symtab, 0, pn, struct nlist_64)
convert_symbol(s1, mo, pn);
}
static int machosymcmp(const void *_a, const void *_b)
{
TCCState *s1 = tcc_state;
int ea = ((struct nlist_64 *)_a)->n_value;
int eb = ((struct nlist_64 *)_b)->n_value;
ElfSym *sa = (ElfSym *)symtab_section->data + ea;
ElfSym *sb = (ElfSym *)symtab_section->data + eb;
int r;
/* locals, then defined externals, then undefined externals, the
last two sections also by name, otherwise stable sort */
r = (ELFW(ST_BIND)(sb->st_info) == STB_LOCAL)
- (ELFW(ST_BIND)(sa->st_info) == STB_LOCAL);
if (r)
return r;
r = (sa->st_shndx == SHN_UNDEF) - (sb->st_shndx == SHN_UNDEF);
if (r)
return r;
if (ELFW(ST_BIND)(sa->st_info) != STB_LOCAL) {
const char * na = (char*)symtab_section->link->data + sa->st_name;
const char * nb = (char*)symtab_section->link->data + sb->st_name;
r = strcmp(na, nb);
if (r)
return r;
}
return ea - eb;
}
static void create_symtab(TCCState *s1, struct macho *mo)
{
int sym_index, sym_end;
struct nlist_64 *pn;
/* Stub creation belongs to check_relocs, but we need to create
the symbol now, so its included in the sorting. */
mo->stubs = new_section(s1, "__stubs", SHT_PROGBITS, SHF_ALLOC | SHF_EXECINSTR);
mo->stubsym = put_elf_sym(s1->symtab, 0, 0,
ELFW(ST_INFO)(STB_LOCAL, STT_SECTION), 0,
mo->stubs->sh_num, ".__stubs");
mo->symtab = new_section(s1, "LESYMTAB", SHT_LINKEDIT, SHF_ALLOC | SHF_WRITE);
mo->strtab = new_section(s1, "LESTRTAB", SHT_LINKEDIT, SHF_ALLOC | SHF_WRITE);
put_elf_str(mo->strtab, " "); /* Mach-O starts strtab with a space */
sym_end = symtab_section->data_offset / sizeof(ElfW(Sym));
pn = section_ptr_add(mo->symtab, sizeof(*pn) * (sym_end - 1));
for (sym_index = 1; sym_index < sym_end; ++sym_index) {
ElfW(Sym) *sym = (ElfW(Sym) *)symtab_section->data + sym_index;
const char *name = (char*)symtab_section->link->data + sym->st_name;
pn[sym_index - 1].n_strx = put_elf_str(mo->strtab, name);
pn[sym_index - 1].n_value = sym_index;
}
tcc_enter_state(s1); /* qsort needs global state */
qsort(pn, sym_end - 1, sizeof(*pn), machosymcmp);
tcc_exit_state(s1);
mo->e2msym = tcc_malloc(sym_end * sizeof(*mo->e2msym));
mo->e2msym[0] = -1;
for (sym_index = 1; sym_index < sym_end; ++sym_index) {
mo->e2msym[pn[sym_index - 1].n_value] = sym_index - 1;
}
}
const struct {
int seg;
uint32_t flags;
const char *name;
} skinfo[sk_last] = {
/*[sk_unknown] =*/ { 0 },
/*[sk_discard] =*/ { 0 },
/*[sk_text] =*/ { 1, S_REGULAR | S_ATTR_PURE_INSTRUCTIONS
| S_ATTR_SOME_INSTRUCTIONS, "__text" },
/*[sk_stubs] =*/ { 0 },
/*[sk_ro_data] =*/ { 1, S_REGULAR, "__rodata" },
/*[sk_uw_info] =*/ { 0 },
/*[sk_nl_ptr] =*/ { 2, S_NON_LAZY_SYMBOL_POINTERS, "__got" },
/*[sk_la_ptr] =*/ { 0 },
/*[sk_init] =*/ { 2, S_MOD_INIT_FUNC_POINTERS, "__mod_init_func" },
/*[sk_fini] =*/ { 2, S_MOD_TERM_FUNC_POINTERS, "__mod_term_func" },
/*[sk_rw_data] =*/ { 2, S_REGULAR, "__data" },
/*[sk_bss] =*/ { 2, S_ZEROFILL, "__bss" },
/*[sk_linkedit] =*/ { 3, S_REGULAR, NULL },
};
static void collect_sections(TCCState *s1, struct macho *mo)
{
int i, sk, numsec;
uint64_t curaddr, fileofs;
Section *s;
struct segment_command_64 *seg = NULL;
struct dylinker_command *dyldlc;
struct symtab_command *symlc;
struct dysymtab_command *dysymlc;
char *str;
seg = add_segment(mo, "__PAGEZERO");
seg->vmsize = (uint64_t)1 << 32;
seg = add_segment(mo, "__TEXT");
seg->vmaddr = (uint64_t)1 << 32;
seg->maxprot = 7; // rwx
seg->initprot = 5; // r-x
seg = add_segment(mo, "__DATA");
seg->vmaddr = -1;
seg->maxprot = 7; // rwx
seg->initprot = 3; // rw-
seg = add_segment(mo, "__LINKEDIT");
seg->vmaddr = -1;
seg->maxprot = 7; // rwx
seg->initprot = 1; // r--
mo->ep = add_lc(mo, LC_MAIN, sizeof(*mo->ep));
mo->ep->entryoff = 4096;
i = (sizeof(*dyldlc) + strlen("/usr/lib/dyld") + 1 + 7) &-8;
dyldlc = add_lc(mo, LC_LOAD_DYLINKER, i);
dyldlc->name = sizeof(*dyldlc);
str = (char*)dyldlc + dyldlc->name;
strcpy(str, "/usr/lib/dyld");
symlc = add_lc(mo, LC_SYMTAB, sizeof(*symlc));
dysymlc = add_lc(mo, LC_DYSYMTAB, sizeof(*dysymlc));
for(i = 0; i < s1->nb_loaded_dlls; i++) {
DLLReference *dllref = s1->loaded_dlls[i];
if (dllref->level == 0)
add_dylib(mo, dllref->name);
}
/* dyld requires a writable segment with classic Mach-O, but it ignores
zero-sized segments for this, so force to have some data. */
section_ptr_add(data_section, 1);
memset (mo->sk_to_sect, 0, sizeof(mo->sk_to_sect));
for (i = s1->nb_sections; i-- > 1;) {
int type, flags;
s = s1->sections[i];
type = s->sh_type;
flags = s->sh_flags;
sk = sk_unknown;
if (flags & SHF_ALLOC) {
switch (type) {
default: sk = sk_unknown; break;
case SHT_INIT_ARRAY: sk = sk_init; break;
case SHT_FINI_ARRAY: sk = sk_fini; break;
case SHT_NOBITS: sk = sk_bss; break;
case SHT_SYMTAB: sk = sk_discard; break;
case SHT_STRTAB: sk = s == stabstr_section ? sk_ro_data : sk_discard; break;
case SHT_RELX: sk = sk_discard; break;
case SHT_LINKEDIT: sk = sk_linkedit; break;
case SHT_PROGBITS:
if (s == s1->got)
sk = sk_nl_ptr;
else if (flags & SHF_EXECINSTR)
sk = sk_text;
else if (flags & SHF_WRITE)
sk = sk_rw_data;
else
sk = sk_ro_data;
break;
}
} else
sk = sk_discard;
s->prev = mo->sk_to_sect[sk].s;
mo->sk_to_sect[sk].s = s;
}
fileofs = 4096; /* leave space for mach-o headers */
curaddr = get_segment(mo, 1)->vmaddr;
curaddr += 4096;
seg = NULL;
numsec = 0;
mo->elfsectomacho = tcc_mallocz(sizeof(*mo->elfsectomacho) * s1->nb_sections);
for (sk = sk_unknown; sk < sk_last; sk++) {
struct section_64 *sec = NULL;
if (seg) {
seg->vmsize = curaddr - seg->vmaddr;
seg->filesize = fileofs - seg->fileoff;
}
if (skinfo[sk].seg && mo->sk_to_sect[sk].s) {
uint64_t al = 0;
int si;
seg = get_segment(mo, skinfo[sk].seg);
if (skinfo[sk].name) {
si = add_section(mo, &seg, skinfo[sk].name);
numsec++;
mo->lc[mo->seg2lc[skinfo[sk].seg]] = (struct load_command*)seg;
mo->sk_to_sect[sk].machosect = si;
sec = get_section(seg, si);
sec->flags = skinfo[sk].flags;
}
if (seg->vmaddr == -1) {
curaddr = (curaddr + 4095) & -4096;
seg->vmaddr = curaddr;
fileofs = (fileofs + 4095) & -4096;
seg->fileoff = fileofs;
}
for (s = mo->sk_to_sect[sk].s; s; s = s->prev) {
int a = exact_log2p1(s->sh_addralign);
if (a && al < (a - 1))
al = a - 1;
s->sh_size = s->data_offset;
}
if (sec)
sec->align = al;
al = 1ULL << al;
if (al > 4096)
tcc_warning("alignment > 4096"), sec->align = 12, al = 4096;
curaddr = (curaddr + al - 1) & -al;
fileofs = (fileofs + al - 1) & -al;
if (sec) {
sec->addr = curaddr;
sec->offset = fileofs;
}
for (s = mo->sk_to_sect[sk].s; s; s = s->prev) {
al = s->sh_addralign;
curaddr = (curaddr + al - 1) & -al;
dprintf("curaddr now 0x%lx\n", (long)curaddr);
s->sh_addr = curaddr;
curaddr += s->sh_size;
if (s->sh_type != SHT_NOBITS) {
fileofs = (fileofs + al - 1) & -al;
s->sh_offset = fileofs;
fileofs += s->sh_size;
dprintf("fileofs now %ld\n", (long)fileofs);
}
if (sec)
mo->elfsectomacho[s->sh_num] = numsec;
}
if (sec)
sec->size = curaddr - sec->addr;
}
if (DEBUG_MACHO)
for (s = mo->sk_to_sect[sk].s; s; s = s->prev) {
int type = s->sh_type;
int flags = s->sh_flags;
printf("%d section %-16s %-10s %09lx %04x %02d %s,%s,%s\n",
sk,
s->name,
type == SHT_PROGBITS ? "progbits" :
type == SHT_NOBITS ? "nobits" :
type == SHT_SYMTAB ? "symtab" :
type == SHT_STRTAB ? "strtab" :
type == SHT_INIT_ARRAY ? "init" :
type == SHT_FINI_ARRAY ? "fini" :
type == SHT_RELX ? "rel" : "???",
(long)s->sh_addr,
(unsigned)s->data_offset,
s->sh_addralign,
flags & SHF_ALLOC ? "alloc" : "",
flags & SHF_WRITE ? "write" : "",
flags & SHF_EXECINSTR ? "exec" : ""
);
}
}
if (seg) {
seg->vmsize = curaddr - seg->vmaddr;
seg->filesize = fileofs - seg->fileoff;
}
/* Fill symtab info */
symlc->symoff = mo->symtab->sh_offset;
symlc->nsyms = mo->symtab->data_offset / sizeof(struct nlist_64);
symlc->stroff = mo->strtab->sh_offset;
symlc->strsize = mo->strtab->data_offset;
dysymlc->iundefsym = mo->iundef == -1 ? symlc->nsyms : mo->iundef;
dysymlc->iextdefsym = mo->iextdef == -1 ? dysymlc->iundefsym : mo->iextdef;
dysymlc->ilocalsym = mo->ilocal == -1 ? dysymlc->iextdefsym : mo->ilocal;
dysymlc->nlocalsym = dysymlc->iextdefsym - dysymlc->ilocalsym;
dysymlc->nextdefsym = dysymlc->iundefsym - dysymlc->iextdefsym;
dysymlc->nundefsym = symlc->nsyms - dysymlc->iundefsym;
dysymlc->indirectsymoff = mo->indirsyms->sh_offset;
dysymlc->nindirectsyms = mo->indirsyms->data_offset / sizeof(uint32_t);
}
static void macho_write(TCCState *s1, struct macho *mo, FILE *fp)
{
int i, sk;
uint64_t fileofs = 0;
Section *s;
mo->mh.mh.magic = MH_MAGIC_64;
mo->mh.mh.cputype = 0x1000007; // x86_64
mo->mh.mh.cpusubtype = 0x80000003;// all | CPU_SUBTYPE_LIB64
mo->mh.mh.filetype = 2; // MH_EXECUTE
mo->mh.mh.flags = 4; // DYLDLINK
mo->mh.mh.ncmds = mo->nlc;
mo->mh.mh.sizeofcmds = 0;
for (i = 0; i < mo->nlc; i++)
mo->mh.mh.sizeofcmds += mo->lc[i]->cmdsize;
fwrite(&mo->mh, 1, sizeof(mo->mh), fp);
fileofs += sizeof(mo->mh);
for (i = 0; i < mo->nlc; i++) {
fwrite(mo->lc[i], 1, mo->lc[i]->cmdsize, fp);
fileofs += mo->lc[i]->cmdsize;
}
for (sk = sk_unknown; sk < sk_last; sk++) {
//struct segment_command_64 *seg;
if (!skinfo[sk].seg || !mo->sk_to_sect[sk].s)
continue;
/*seg =*/ get_segment(mo, skinfo[sk].seg);
for (s = mo->sk_to_sect[sk].s; s; s = s->prev) {
if (s->sh_type != SHT_NOBITS) {
while (fileofs < s->sh_offset)
fputc(0, fp), fileofs++;
if (s->sh_size) {
fwrite(s->data, 1, s->sh_size, fp);
fileofs += s->sh_size;
}
}
}
}
}
ST_FUNC int macho_output_file(TCCState *s1, const char *filename)
{
int fd, mode, file_type;
FILE *fp;
int i, ret = -1;
struct macho mo;
(void)memset(&mo, 0, sizeof(mo));
file_type = s1->output_type;
if (file_type == TCC_OUTPUT_OBJ)
mode = 0666;
else
mode = 0777;
unlink(filename);
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, mode);
if (fd < 0 || (fp = fdopen(fd, "wb")) == NULL) {
tcc_error_noabort("could not write '%s: %s'", filename, strerror(errno));
return -1;
}
if (s1->verbose)
printf("<- %s\n", filename);
tcc_add_runtime(s1);
resolve_common_syms(s1);
create_symtab(s1, &mo);
check_relocs(s1, &mo);
ret = check_symbols(s1, &mo);
if (!ret) {
collect_sections(s1, &mo);
relocate_syms(s1, s1->symtab, 0);
mo.ep->entryoff = get_sym_addr(s1, "main", 1, 1)
- get_segment(&mo, 1)->vmaddr;
if (s1->nb_errors)
goto do_ret;
relocate_sections(s1);
convert_symbols(s1, &mo);
macho_write(s1, &mo, fp);
}
do_ret:
for (i = 0; i < mo.nlc; i++)
tcc_free(mo.lc[i]);
tcc_free(mo.lc);
tcc_free(mo.elfsectomacho);
tcc_free(mo.e2msym);
fclose(fp);
return ret;
}
static uint32_t macho_swap32(uint32_t x)
{
return (x >> 24) | (x << 24) | ((x >> 8) & 0xff00) | ((x & 0xff00) << 8);
}
#define SWAP(x) (swap ? macho_swap32(x) : (x))
ST_FUNC int macho_add_dllref(TCCState* s1, int lev, const char* soname)
{
/* if the dll is already loaded, do not load it */
DLLReference *dllref;
int i;
for(i = 0; i < s1->nb_loaded_dlls; i++) {
dllref = s1->loaded_dlls[i];
if (!strcmp(soname, dllref->name)) {
/* but update level if needed */
if (lev < dllref->level)
dllref->level = lev;
return -1;
}
}
tcc_add_dllref(s1, soname)->level = lev;
return 0;
}
#define tbd_parse_movepast(s) \
(pos = (pos = strstr(pos, s)) ? pos + strlen(s) : NULL)
#define tbd_parse_movetoany(cs) (pos = strpbrk(pos, cs))
#define tbd_parse_skipws while (*pos && (*pos==' '||*pos=='\n')) ++pos
#define tbd_parse_tramplequote if(*pos=='\''||*pos=='"') tbd_parse_trample
#define tbd_parse_tramplespace if(*pos==' ') tbd_parse_trample
#define tbd_parse_trample *pos++=0
#ifdef TCC_IS_NATIVE
/* Looks for the active developer SDK set by xcode-select (or the default
one set during installation.) */
ST_FUNC void tcc_add_macos_sdkpath(TCCState* s)
{
char *sdkroot = NULL, *pos = NULL;
void* xcs = dlopen("libxcselect.dylib", RTLD_GLOBAL | RTLD_LAZY);
CString path;
int (*f)(unsigned int, char**) = dlsym(xcs, "xcselect_host_sdk_path");
cstr_new(&path);
if (f) f(1, &sdkroot);
if (sdkroot)
pos = strstr(sdkroot,"SDKs/MacOSX");
if (pos)
cstr_printf(&path, "%.*s.sdk/usr/lib", (int)(pos - sdkroot + 11), sdkroot);
/* must use free from libc directly */
#pragma push_macro("free")
#undef free
free(sdkroot);
#pragma pop_macro("free")
if (path.size)
tcc_add_library_path(s, (char*)path.data);
else
tcc_add_library_path(s,
"/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/lib"
":" "/Applications/Xcode.app/Developer/SDKs/MacOSX.sdk/usr/lib"
);
cstr_free(&path);
}
ST_FUNC const char* macho_tbd_soname(const char* filename) {
char *soname, *data, *pos;
const char *ret = filename;
int fd = open(filename,O_RDONLY);
if (fd<0) return ret;
pos = data = tcc_load_text(fd);
if (!tbd_parse_movepast("install-name: ")) goto the_end;
tbd_parse_skipws;
tbd_parse_tramplequote;
soname = pos;
if (!tbd_parse_movetoany("\n \"'")) goto the_end;
tbd_parse_trample;
ret = tcc_strdup(soname);
the_end:
tcc_free(data);
return ret;
}
#endif /* TCC_IS_NATIVE */
ST_FUNC int macho_load_tbd(TCCState* s1, int fd, const char* filename, int lev)
{
char *soname, *data, *pos;
int ret = -1;
pos = data = tcc_load_text(fd);
if (!tbd_parse_movepast("install-name: ")) goto the_end;
tbd_parse_skipws;
tbd_parse_tramplequote;
soname = pos;
if (!tbd_parse_movetoany("\n \"'")) goto the_end;
tbd_parse_trample;
ret = 0;
if (macho_add_dllref(s1, lev, soname) != 0) goto the_end;
while(pos) {
char* sym = NULL;
int cont = 1;
if (!tbd_parse_movepast("symbols: ")) break;
if (!tbd_parse_movepast("[")) break;
while (cont) {
tbd_parse_skipws;
tbd_parse_tramplequote;
sym = pos;
if (!tbd_parse_movetoany(",] \"'")) break;
tbd_parse_tramplequote;
tbd_parse_tramplespace;
tbd_parse_skipws;
if (*pos==0||*pos==']') cont=0;
tbd_parse_trample;
set_elf_sym(s1->dynsymtab_section, 0, 0,
ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0, SHN_UNDEF, sym);
}
}
the_end:
tcc_free(data);
return ret;
}
ST_FUNC int macho_load_dll(TCCState * s1, int fd, const char* filename, int lev)
{
unsigned char buf[sizeof(struct mach_header_64)];
void *buf2;
uint32_t machofs = 0;
struct fat_header fh;
struct mach_header mh;
struct load_command *lc;
int i, swap = 0;
const char *soname = filename;
struct nlist_64 *symtab = 0;
uint32_t nsyms = 0;
char *strtab = 0;
uint32_t strsize = 0;
uint32_t iextdef = 0;
uint32_t nextdef = 0;
again:
if (full_read(fd, buf, sizeof(buf)) != sizeof(buf))
return -1;
memcpy(&fh, buf, sizeof(fh));
if (fh.magic == FAT_MAGIC || fh.magic == FAT_CIGAM) {
struct fat_arch *fa = load_data(fd, sizeof(fh),
fh.nfat_arch * sizeof(*fa));
swap = fh.magic == FAT_CIGAM;
for (i = 0; i < SWAP(fh.nfat_arch); i++)
if (SWAP(fa[i].cputype) == 0x01000007 /* CPU_TYPE_X86_64 */
&& SWAP(fa[i].cpusubtype) == 3) /* CPU_SUBTYPE_X86_ALL */
break;
if (i == SWAP(fh.nfat_arch)) {
tcc_free(fa);
return -1;
}
machofs = SWAP(fa[i].offset);
tcc_free(fa);
lseek(fd, machofs, SEEK_SET);
goto again;
} else if (fh.magic == FAT_MAGIC_64 || fh.magic == FAT_CIGAM_64) {
tcc_warning("%s: Mach-O fat 64bit files of type 0x%x not handled",
filename, fh.magic);
return -1;
}
memcpy(&mh, buf, sizeof(mh));
if (mh.magic != MH_MAGIC_64)
return -1;
dprintf("found Mach-O at %d\n", machofs);
buf2 = load_data(fd, machofs + sizeof(struct mach_header_64), mh.sizeofcmds);
for (i = 0, lc = buf2; i < mh.ncmds; i++) {
dprintf("lc %2d: 0x%08x\n", i, lc->cmd);
switch (lc->cmd) {
case LC_SYMTAB:
{
struct symtab_command *sc = (struct symtab_command*)lc;
nsyms = sc->nsyms;
symtab = load_data(fd, machofs + sc->symoff, nsyms * sizeof(*symtab));
strsize = sc->strsize;
strtab = load_data(fd, machofs + sc->stroff, strsize);
break;
}
case LC_ID_DYLIB:
{
struct dylib_command *dc = (struct dylib_command*)lc;
soname = (char*)lc + dc->name;
dprintf(" ID_DYLIB %d 0x%x 0x%x %s\n",
dc->timestamp, dc->current_version,
dc->compatibility_version, soname);
break;
}
case LC_REEXPORT_DYLIB:
{
struct dylib_command *dc = (struct dylib_command*)lc;
char *name = (char*)lc + dc->name;
int subfd = open(name, O_RDONLY | O_BINARY);
dprintf(" REEXPORT %s\n", name);
if (subfd < 0)
tcc_warning("can't open %s (reexported from %s)", name, filename);
else {
/* Hopefully the REEXPORTs never form a cycle, we don't check
for that! */
macho_load_dll(s1, subfd, name, lev + 1);
close(subfd);
}
break;
}
case LC_DYSYMTAB:
{
struct dysymtab_command *dc = (struct dysymtab_command*)lc;
iextdef = dc->iextdefsym;
nextdef = dc->nextdefsym;
break;
}
}
lc = (struct load_command*) ((char*)lc + lc->cmdsize);
}
if (0 != macho_add_dllref(s1, lev, soname))
goto the_end;
if (!nsyms || !nextdef)
tcc_warning("%s doesn't export any symbols?", filename);
//dprintf("symbols (all):\n");
dprintf("symbols (exported):\n");
dprintf(" n: typ sec desc value name\n");
//for (i = 0; i < nsyms; i++) {
for (i = iextdef; i < iextdef + nextdef; i++) {
struct nlist_64 *sym = symtab + i;
dprintf("%5d: %3d %3d 0x%04x 0x%016lx %s\n",
i, sym->n_type, sym->n_sect, sym->n_desc, (long)sym->n_value,
strtab + sym->n_strx);
set_elf_sym(s1->dynsymtab_section, 0, 0,
ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE),
0, SHN_UNDEF, strtab + sym->n_strx);
}
the_end:
tcc_free(strtab);
tcc_free(symtab);
tcc_free(buf2);
return 0;
}
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