mirror of
https://github.com/netwide-assembler/nasm.git
synced 2024-11-21 03:14:19 +08:00
Add basic support for Mach-O file format.
This commit is contained in:
Eric Christopher
parent
f3071da71e
commit
1b8a72ae7c
@ -51,7 +51,7 @@ NASM = nasm.$(O) nasmlib.$(O) float.$(O) insnsa.$(O) assemble.$(O) \
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labels.$(O) parser.$(O) outform.$(O) output/outbin.$(O) \
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output/outaout.$(O) output/outcoff.$(O) output/outelf.$(O) \
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output/outobj.$(O) output/outas86.$(O) output/outrdf2.$(O) \
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output/outdbg.$(O) output/outieee.$(O) \
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output/outdbg.$(O) output/outieee.$(O) output/outmacho.$(O) \
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preproc.$(O) listing.$(O) eval.$(O)
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NDISASM = ndisasm.$(O) disasm.$(O) sync.$(O) nasmlib.$(O) insnsd.$(O)
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15
outform.h
15
outform.h
@ -57,7 +57,7 @@
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/* ====configurable info begins here==== */
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/* formats configurable:
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* bin,obj,elf,aout,aoutb,coff,win32,as86,rdf2 */
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* bin,obj,elf,aout,aoutb,coff,win32,as86,rdf2,macho */
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/* process options... */
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@ -98,6 +98,9 @@
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#ifndef OF_IEEE
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#define OF_IEEE
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#endif
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#ifndef OF_MACHO
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#define OF_MACHO
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#endif
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#endif /* OF_ALL */
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/* turn on groups of formats specified.... */
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@ -141,6 +144,9 @@
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#ifndef OF_IEEE
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#define OF_IEEE
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#endif
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#ifndef OF_MACHO
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#define OF_MACHO
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#endif
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#endif
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/* finally... override any format specifically specified to be off */
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@ -174,6 +180,9 @@
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#ifdef OF_NO_IEEE
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#undef OF_IEEE
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#endif
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#ifdef OF_NO_MACHO
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#undef OF_MACHO
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#endif
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#ifndef OF_DEFAULT
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#define OF_DEFAULT of_bin
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@ -194,6 +203,7 @@ extern struct ofmt of_obj;
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extern struct ofmt of_win32;
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extern struct ofmt of_rdf2;
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extern struct ofmt of_ieee;
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extern struct ofmt of_macho;
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extern struct ofmt of_dbg;
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struct ofmt *drivers[] = {
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@ -227,6 +237,9 @@ struct ofmt *drivers[] = {
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#ifdef OF_IEEE
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&of_ieee,
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#endif
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#ifdef OF_MACHO
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&of_macho,
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#endif
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#ifdef OF_DBG
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&of_dbg,
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#endif
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925
output/outmacho.c
Normal file
925
output/outmacho.c
Normal file
@ -0,0 +1,925 @@
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/* outmacho.c output routines for the Netwide Assembler to produce
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* NeXTstep/OpenStep/Rhapsody/Darwin/MacOS X object files
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*
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* The Netwide Assembler is copyright (C) 1996 Simon Tatham and
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* Julian Hall. All rights reserved. The software is
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* redistributable under the licence given in the file "Licence"
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* distributed in the NASM archive.
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*/
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/* Most of this file is, like Mach-O itself, based on a.out. For more
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* guidelines see outaout.c. */
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <ctype.h>
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#include "nasm.h"
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#include "nasmlib.h"
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#include "outform.h"
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#if defined(OF_MACHO)
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/* Mach-O in-file header structure sizes */
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#define MACHO_HEADER_SIZE (28)
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#define MACHO_SEGCMD_SIZE (56)
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#define MACHO_SECTCMD_SIZE (68)
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#define MACHO_SYMCMD_SIZE (24)
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#define MACHO_NLIST_SIZE (12)
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#define MACHO_RELINFO_SIZE (8)
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/* Mach-O file header values */
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#define MH_MAGIC (0xfeedface)
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#define CPU_TYPE_I386 (7) /* x86 platform */
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#define CPU_SUBTYPE_I386_ALL (3) /* all-x86 compatible */
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#define MH_OBJECT (0x1) /* object file */
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#define LC_SEGMENT (0x1) /* segment load command */
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#define LC_SYMTAB (0x2) /* symbol table load command */
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#define VM_PROT_NONE (0x00)
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#define VM_PROT_READ (0x01)
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#define VM_PROT_WRITE (0x02)
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#define VM_PROT_EXECUTE (0x04)
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#define VM_PROT_DEFAULT (VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE)
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#define VM_PROT_ALL (VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE)
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struct section {
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/* nasm internal data */
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struct section *next;
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struct SAA *data;
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long index;
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struct reloc *relocs;
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/* data that goes into the file */
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char sectname[16]; /* what this section is called */
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char segname[16]; /* segment this section will be in */
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unsigned long size; /* in-memory and -file size */
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unsigned long nreloc; /* relocation entry count */
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unsigned long flags; /* type and attributes (masked) */
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};
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#define SECTION_TYPE 0x000000ff /* section type mask */
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#define S_REGULAR (0x0) /* standard section */
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#define S_ZEROFILL (0x1) /* zerofill, in-memory only */
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static struct sectmap {
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const char *nasmsect;
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const char *segname;
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const char *sectname;
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const long flags;
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} sectmap[] = {{".text", "__TEXT", "__text", S_REGULAR},
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{".data", "__DATA", "__data", S_REGULAR},
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{".bss", "__DATA", "__bss", S_ZEROFILL},
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{NULL, NULL, NULL}};
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struct reloc {
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/* nasm internal data */
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struct reloc *next;
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/* data that goes into the file */
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long addr; /* op's offset in section */
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unsigned int snum:24, /* contains symbol index if
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** ext otherwise in-file
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** section number */
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pcrel:1, /* relative relocation */
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length:2, /* 0=byte, 1=word, 2=long */
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ext:1, /* external symbol referenced */
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type:4; /* reloc type, 0 for us */
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};
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#define R_ABS 0 /* absolute relocation */
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#define R_SCATTERED 0x80000000 /* reloc entry is scattered if
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** highest bit == 1 */
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struct symbol {
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long strx; /* string table index */
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unsigned char type; /* symbol type */
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unsigned char sect; /* NO_SECT or section number */
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short desc; /* for stab debugging, 0 for us */
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unsigned long value; /* offset of symbol in section */
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};
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/* symbol type bits */
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#define N_EXT 0x01 /* global or external symbol */
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#define N_UNDF 0x0 /* undefined symbol | n_sect == */
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#define N_ABS 0x2 /* absolute symbol | NO_SECT */
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#define N_SECT 0xe /* defined symbol, n_sect holds
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** section number */
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#define N_TYPE 0x0e /* type bit mask */
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/* special section number values */
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#define NO_SECT 0 /* no section, invalid */
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#define MAX_SECT 255 /* maximum number of sections */
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static struct section *sects, **sectstail;
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static struct SAA *syms;
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static unsigned long nsyms;
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static struct RAA *extsyms;
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static struct SAA *strs;
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static unsigned long strslen;
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static FILE *machofp;
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static efunc error;
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static evalfunc evaluate;
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extern struct ofmt of_macho;
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#define xstrncpy(xdst, xsrc) \
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memset(xdst, '\0', sizeof(xdst)); /* zero out whole buffer */ \
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strncpy(xdst, xsrc, sizeof(xdst)); /* copy over string */ \
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xdst[sizeof(xdst) - 1] = '\0'; /* proper null-termination */
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#define align(x, y) \
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(((x) + (y) - 1) & ~((y) - 1)) /* align x to multiple of y */
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#define alignlong(x) \
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align(x, sizeof(long)) /* align x to long boundary */
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static struct section *get_section_by_name(const char *segname,
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const char *sectname) {
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struct section *s;
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for (s = sects; s != NULL; s = s->next)
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if (!strcmp(s->segname, segname) &&
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!strcmp(s->sectname, sectname))
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break;
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return s;
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}
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static struct section *get_section_by_index(const long index) {
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struct section *s;
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for (s = sects; s != NULL; s = s->next)
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if (index == s->index)
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break;
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return s;
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}
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static long get_section_index_by_name(const char *segname,
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const char *sectname) {
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struct section *s;
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for (s = sects; s != NULL; s = s->next)
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if (!strcmp(s->segname, segname) &&
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!strcmp(s->sectname, sectname))
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return s->index;
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return -1;
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}
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static char *get_section_name_by_index(const long index) {
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struct section *s;
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for (s = sects; s != NULL; s = s->next)
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if (index == s->index)
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return s->sectname;
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return NULL;
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}
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static unsigned char get_section_fileindex_by_index(const long index) {
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struct section *s;
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unsigned char i = 1;
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for (s = sects; s != NULL && i < MAX_SECT; s = s->next, ++i)
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if (index == s->index)
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return i;
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if (i == MAX_SECT)
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error(ERR_WARNING, "too many sections (>255) - clipped by fileindex");
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return NO_SECT;
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}
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static void macho_init(FILE *fp, efunc errfunc, ldfunc ldef, evalfunc eval)
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{
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char zero = 0;
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machofp = fp;
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error = errfunc;
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evaluate = eval;
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(void) ldef; /* placate optimisers */
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sects = NULL;
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sectstail = §s;
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syms = saa_init((long)sizeof(struct symbol));
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nsyms = 0;
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extsyms = raa_init();
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strs = saa_init(1L);
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/* string table starts with a zero byte - don't ask why */
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saa_wbytes(strs, &zero, sizeof(char));
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strslen = 1;
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}
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static int macho_setinfo(enum geninfo type, char **val)
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{
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return 0;
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}
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static void sect_write(struct section *sect,
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const unsigned char *data, unsigned long len)
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{
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saa_wbytes(sect->data, data, len);
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sect->size += len;
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}
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static void add_reloc(struct section *sect, long section,
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int pcrel, int bytes) {
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struct reloc *r;
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long fi;
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/* NeXT as puts relocs in reversed order (address-wise) into the
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** files, so we do the same, doesn't seem to make much of a
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** difference either way */
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r = nasm_malloc(sizeof(struct reloc));
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r->next = sect->relocs;
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sect->relocs = r;
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/* the current end of the section will be the symbol's address for
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** now, might have to be fixed by fixup_relocs() later on. make
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** sure, we don't make the symbol scattered by setting the highest
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** bit by accident */
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r->addr = sect->size & ~R_SCATTERED;
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r->ext = 0;
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r->pcrel = pcrel;
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/* match byte count 1, 2, 4 to length codes 0, 1, 2 respectively */
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r->length = bytes >> 1;
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/* vanilla relocation (GENERIC_RELOC_VANILLA) */
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r->type = 0;
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if (section == NO_SEG) {
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/* absolute local symbol if no section index given */
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r->snum = R_ABS;
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} else {
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fi = get_section_fileindex_by_index(section);
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if (fi == NO_SECT) {
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/* external symbol if no section with that index known,
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** symbol number was saved in macho_symdef() */
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r->snum = raa_read(extsyms, section);
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r->ext = 1;
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} else {
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/* local symbol in section fi */
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r->snum = fi;
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}
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}
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++sect->nreloc;
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}
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static void macho_output(long secto, const void *data, unsigned long type,
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long section, long wrt)
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{
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struct section *s, *sbss;
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long realbytes = type & OUT_SIZMASK;
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long addr;
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unsigned char mydata[4], *p;
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type &= OUT_TYPMASK;
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if (wrt != NO_SEG) {
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wrt = NO_SEG;
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error(ERR_NONFATAL, "WRT not supported by Mach-O output format");
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/* continue to do _something_ */
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}
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if (secto == NO_SEG) {
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if (type != OUT_RESERVE)
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error(ERR_NONFATAL, "attempt to assemble code in "
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"[ABSOLUTE] space");
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return;
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}
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s = get_section_by_index(secto);
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if (s == NULL) {
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error(ERR_WARNING, "attempt to assemble code in"
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" section %d: defaulting to `.text'", secto);
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s = get_section_by_name("__TEXT", "__text");
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/* should never happen */
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if (s == NULL)
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error(ERR_PANIC, "text section not found");
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}
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sbss = get_section_by_name("__DATA", "__bss");
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if (s == sbss && type != OUT_RESERVE) {
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error(ERR_WARNING, "attempt to initialise memory in the"
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" BSS section: ignored");
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switch (type) {
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case OUT_REL2ADR:
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realbytes = 2;
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break;
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case OUT_REL4ADR:
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realbytes = 4;
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break;
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default:
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break;
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}
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s->size += realbytes;
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return;
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}
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switch (type) {
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case OUT_RESERVE:
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if (s != sbss) {
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error(ERR_WARNING, "uninitialised space declared in"
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" %s section: zeroing",
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get_section_name_by_index(secto));
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sect_write(s, NULL, realbytes);
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} else
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s->size += realbytes;
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break;
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case OUT_RAWDATA:
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if (section != NO_SEG)
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error(ERR_PANIC, "OUT_RAWDATA with other than NO_SEG");
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sect_write(s, data, realbytes);
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break;
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case OUT_ADDRESS:
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addr = *(long *)data;
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if (section != NO_SEG) {
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if (section % 2) {
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error(ERR_NONFATAL, "Mach-O format does not support"
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" section base references");
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} else
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add_reloc(s, section, 0, realbytes);
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}
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p = mydata;
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if (realbytes == 2)
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WRITESHORT(p, addr);
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else
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WRITELONG(p, addr);
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sect_write(s, mydata, realbytes);
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break;
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case OUT_REL2ADR:
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if (section == secto)
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error(ERR_PANIC, "intra-section OUT_REL2ADR");
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if (section != NO_SEG && section % 2) {
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error(ERR_NONFATAL, "Mach-O format does not support"
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" section base references");
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} else
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add_reloc(s, section, 1, 2);
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p = mydata;
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WRITESHORT(p, *(long*)data - (realbytes + s->size));
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sect_write(s, mydata, 2L);
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break;
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case OUT_REL4ADR:
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if (section == secto)
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error(ERR_PANIC, "intra-section OUT_REL4ADR");
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if (section != NO_SEG && section % 2) {
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error(ERR_NONFATAL, "Mach-O format does not support"
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" section base references");
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} else
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add_reloc(s, section, 1, 4);
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p = mydata;
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WRITELONG(p, *(long*)data - (realbytes + s->size));
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sect_write(s, mydata, 4L);
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break;
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default:
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error(ERR_PANIC, "unknown output type?");
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break;
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}
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}
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static long macho_section(char *name, int pass, int *bits)
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{
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long index;
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struct sectmap *sm;
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struct section *s;
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/* Default to 32 bits. */
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if (!name)
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*bits = 32;
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if (!name)
|
||||
name = ".text";
|
||||
|
||||
for (sm = sectmap; sm->nasmsect != NULL; ++sm) {
|
||||
/* make lookup into section name translation table */
|
||||
if (!strcmp(name, sm->nasmsect)) {
|
||||
/* try to find section with that name */
|
||||
index = get_section_index_by_name(sm->segname, sm->sectname);
|
||||
|
||||
/* create it if it doesn't exist yet */
|
||||
if (index == -1) {
|
||||
s = *sectstail = nasm_malloc(sizeof(struct section));
|
||||
s->next = NULL;
|
||||
sectstail = &s->next;
|
||||
|
||||
s->data = saa_init(1L);
|
||||
s->index = seg_alloc();
|
||||
s->relocs = NULL;
|
||||
|
||||
xstrncpy(s->segname, sm->segname);
|
||||
xstrncpy(s->sectname, sm->sectname);
|
||||
s->size = 0;
|
||||
s->nreloc = 0;
|
||||
s->flags = sm->flags;
|
||||
|
||||
index = s->index;
|
||||
}
|
||||
|
||||
return index;
|
||||
}
|
||||
}
|
||||
|
||||
error(ERR_PANIC, "invalid section name %s", name);
|
||||
return NO_SEG;
|
||||
}
|
||||
|
||||
static void macho_symdef(char *name, long section, long offset,
|
||||
int is_global, char *special)
|
||||
{
|
||||
struct symbol *sym;
|
||||
|
||||
if (special) {
|
||||
error(ERR_NONFATAL, "The Mach-O output format does "
|
||||
"not support any special symbol types");
|
||||
return;
|
||||
}
|
||||
|
||||
if (is_global == 3) {
|
||||
error(ERR_NONFATAL, "The Mach-O format does not "
|
||||
"(yet) support forward reference fixups.");
|
||||
return;
|
||||
}
|
||||
|
||||
sym = saa_wstruct(syms);
|
||||
|
||||
sym->strx = strslen;
|
||||
sym->type = 0;
|
||||
sym->desc = 0;
|
||||
sym->value = offset;
|
||||
|
||||
/* external and common symbols get N_EXT */
|
||||
if (is_global != 0)
|
||||
sym->type |= N_EXT;
|
||||
|
||||
if (section == NO_SEG) {
|
||||
/* symbols in no section get absolute */
|
||||
sym->type |= N_ABS;
|
||||
sym->sect = NO_SECT;
|
||||
} else {
|
||||
sym->type |= N_SECT;
|
||||
|
||||
/* get the in-file index of the section the symbol was defined in */
|
||||
sym->sect = get_section_fileindex_by_index(section);
|
||||
|
||||
if (sym->sect == NO_SECT) {
|
||||
/* remember symbol number of references to external
|
||||
** symbols, this works because every external symbol gets
|
||||
** its own section number allocated internally by nasm and
|
||||
** can so be used as a key */
|
||||
extsyms = raa_write(extsyms, section, nsyms);
|
||||
|
||||
switch (is_global) {
|
||||
case 1:
|
||||
case 2:
|
||||
/* there isn't actually a difference between global
|
||||
** and common symbols, both even have their size in
|
||||
** sym->value */
|
||||
sym->type = N_EXT;
|
||||
break;
|
||||
|
||||
default:
|
||||
/* give an error on unfound section if it's not an
|
||||
** external or common symbol (assemble_file() does a
|
||||
** seg_alloc() on every call for them) */
|
||||
error(ERR_PANIC, "in-file index for section %d not found",
|
||||
section);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* append symbol name to string table */
|
||||
saa_wbytes(strs, name, (long)(strlen(name) + 1));
|
||||
strslen += strlen(name) + 1;
|
||||
|
||||
++nsyms;
|
||||
}
|
||||
|
||||
static long macho_segbase(long section)
|
||||
{
|
||||
return section;
|
||||
}
|
||||
|
||||
static int macho_directive(char *directive, char *value, int pass)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void macho_filename(char *inname, char *outname, efunc error)
|
||||
{
|
||||
standard_extension(inname, outname, ".o", error);
|
||||
}
|
||||
|
||||
static const char *macho_stdmac[] = {
|
||||
"%define __SECT__ [section .text]",
|
||||
"%macro __NASM_CDecl__ 1",
|
||||
"%endmacro",
|
||||
NULL
|
||||
};
|
||||
|
||||
static void macho_cleanup(int debuginfo)
|
||||
{
|
||||
struct section *s;
|
||||
struct reloc *r;
|
||||
unsigned long offset, rel_padcnt = 0;
|
||||
unsigned long head_ncmds = 0;
|
||||
unsigned long head_sizeofcmds = 0;
|
||||
unsigned long seg_nsects = 0;
|
||||
unsigned long seg_filesize = 0;
|
||||
unsigned long seg_vmsize = 0;
|
||||
|
||||
(void) debuginfo;
|
||||
|
||||
/* mach-o object file structure:
|
||||
**
|
||||
** mach header
|
||||
** ulong magic
|
||||
** int cpu type
|
||||
** int cpu subtype
|
||||
** ulong mach file type
|
||||
** ulong number of load commands
|
||||
** ulong size of all load commands
|
||||
** (includes section struct size of segment command)
|
||||
** ulong flags
|
||||
**
|
||||
** segment command
|
||||
** ulong command type == LC_SEGMENT
|
||||
** ulong size of load command
|
||||
** (including section load commands)
|
||||
** char[16] segment name
|
||||
** ulong in-memory offset
|
||||
** ulong in-memory size
|
||||
** ulong in-file offset to data area
|
||||
** ulong in-file size
|
||||
** (in-memory size excluding zerofill sections)
|
||||
** int maximum vm protection
|
||||
** int initial vm protection
|
||||
** ulong number of sections
|
||||
** ulong flags
|
||||
**
|
||||
** section commands
|
||||
** char[16] section name
|
||||
** char[16] segment name
|
||||
** ulong in-memory offset
|
||||
** ulong in-memory size
|
||||
** ulong in-file offset
|
||||
** ulong alignment
|
||||
** (irrelevant in MH_OBJECT)
|
||||
** ulong in-file offset of relocation entires
|
||||
** ulong number of relocations
|
||||
** ulong flags
|
||||
** ulong reserved
|
||||
** ulong reserved
|
||||
**
|
||||
** symbol table command
|
||||
** ulong command type == LC_SYMTAB
|
||||
** ulong size of load command
|
||||
** ulong symbol table offset
|
||||
** ulong number of symbol table entries
|
||||
** ulong string table offset
|
||||
** ulong string table size
|
||||
**
|
||||
** raw section data
|
||||
**
|
||||
** padding to long boundary
|
||||
**
|
||||
** relocation data (struct reloc)
|
||||
** long offset
|
||||
** uint data (symbolnum, pcrel, length, extern, type)
|
||||
**
|
||||
** symbol table data (struct nlist)
|
||||
** long string table entry number
|
||||
** uchar type
|
||||
** (extern, absolute, defined in section)
|
||||
** uchar section
|
||||
** (0 for global symbols, section number of definition (>= 1, <=
|
||||
** 254) for local symbols, size of variable for common symbols
|
||||
** [type == extern])
|
||||
** short description
|
||||
** (for stab debugging format)
|
||||
** ulong value (i.e. file offset) of symbol or stab offset
|
||||
**
|
||||
** string table data
|
||||
** list of null-terminated strings
|
||||
*/
|
||||
|
||||
/* simplifications over native NeXTstep assembler:
|
||||
** - no support for dynamic linking/symbols/libraries, section differences
|
||||
** - no sorting of symbols and string table, normally its ordered like
|
||||
** - local symbols, defined external symbols, undefined external symbols
|
||||
** - strings for external symbols, strings for local symbols
|
||||
** we just dump them in the order given by the source file and nasm what
|
||||
** seems to work fine with the link editor
|
||||
*/
|
||||
|
||||
/* first calculate and finalise all needed values */
|
||||
|
||||
/* count sections and calculate in-memory and in-file offsets */
|
||||
for (s = sects; s != NULL; s = s->next) {
|
||||
/* zerofill sections aren't actually written to the file */
|
||||
if ((s->flags & SECTION_TYPE) != S_ZEROFILL)
|
||||
seg_filesize += s->size;
|
||||
|
||||
seg_vmsize += s->size;
|
||||
++seg_nsects;
|
||||
}
|
||||
|
||||
/* 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) {
|
||||
++head_ncmds;
|
||||
head_sizeofcmds += MACHO_SEGCMD_SIZE + seg_nsects * MACHO_SECTCMD_SIZE;
|
||||
}
|
||||
|
||||
if (nsyms > 0) {
|
||||
++head_ncmds;
|
||||
head_sizeofcmds += MACHO_SYMCMD_SIZE;
|
||||
}
|
||||
|
||||
/* emit the Mach-O header. */
|
||||
fwritelong(MH_MAGIC, machofp); /* magic */
|
||||
fwritelong(CPU_TYPE_I386, machofp); /* CPU type */
|
||||
fwritelong(CPU_SUBTYPE_I386_ALL, machofp); /* CPU subtype */
|
||||
fwritelong(MH_OBJECT, machofp); /* Mach-O file type */
|
||||
fwritelong(head_ncmds, machofp); /* number of load commands */
|
||||
fwritelong(head_sizeofcmds, machofp); /* size of load commands */
|
||||
fwritelong(0, machofp); /* no flags */
|
||||
|
||||
offset = MACHO_HEADER_SIZE + head_sizeofcmds;
|
||||
|
||||
/* emit the segment load command */
|
||||
if (seg_nsects > 0) {
|
||||
unsigned long s_addr = 0;
|
||||
unsigned long rel_base = alignlong(offset + seg_filesize);
|
||||
unsigned long s_reloff = 0;
|
||||
|
||||
fwritelong(LC_SEGMENT, machofp); /* cmd == LC_SEGMENT */
|
||||
|
||||
/* size of load command including section load commands */
|
||||
fwritelong(MACHO_SEGCMD_SIZE + seg_nsects *
|
||||
MACHO_SECTCMD_SIZE, machofp);
|
||||
|
||||
/* in an MH_OBJECT file all sections are in one unnamed (name
|
||||
** all zeros) segment */
|
||||
fwrite("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16, 1, machofp);
|
||||
fwritelong(0, machofp); /* in-memory offset */
|
||||
fwritelong(seg_vmsize, machofp); /* in-memory size */
|
||||
fwritelong(offset, machofp); /* in-file offset to data */
|
||||
fwritelong(seg_filesize, machofp); /* in-file size */
|
||||
fwritelong(VM_PROT_DEFAULT, machofp); /* maximum vm protection */
|
||||
fwritelong(VM_PROT_DEFAULT, machofp); /* initial vm protection */
|
||||
fwritelong(seg_nsects, machofp); /* number of sections */
|
||||
fwritelong(0, machofp) ; /* no flags */
|
||||
|
||||
/* emit section headers */
|
||||
for (s = sects; s != NULL; s = s->next) {
|
||||
fwrite(s->sectname, sizeof(s->sectname), 1, machofp);
|
||||
fwrite(s->segname, sizeof(s->segname), 1, machofp);
|
||||
fwritelong(s_addr, machofp);
|
||||
fwritelong(s->size, machofp);
|
||||
|
||||
/* dummy data for zerofill sections or proper values */
|
||||
if ((s->flags & SECTION_TYPE) != S_ZEROFILL) {
|
||||
fwritelong(offset, machofp);
|
||||
fwritelong(0, machofp);
|
||||
/* To be compatible with cctools as we emit
|
||||
a zero reloff if we have no relocations. */
|
||||
fwritelong(s->nreloc ? rel_base + s_reloff : 0,
|
||||
machofp);
|
||||
fwritelong(s->nreloc, machofp);
|
||||
|
||||
offset += s->size;
|
||||
s_reloff += s->nreloc * MACHO_RELINFO_SIZE;
|
||||
} else {
|
||||
fwritelong(0, machofp);
|
||||
fwritelong(0, machofp);
|
||||
fwritelong(0, machofp);
|
||||
fwritelong(0, machofp);
|
||||
}
|
||||
|
||||
fwritelong(s->flags, machofp); /* flags */
|
||||
fwritelong(0, machofp); /* reserved */
|
||||
fwritelong(0, machofp); /* reserved */
|
||||
|
||||
s_addr += s->size;
|
||||
}
|
||||
|
||||
/* at this point offset has reached rel_base - alignment,
|
||||
** remember how much we'll have to pad and skip relocation
|
||||
** data */
|
||||
rel_padcnt = rel_base - offset;
|
||||
offset = rel_base + s_reloff;
|
||||
} else
|
||||
error(ERR_WARNING, "no sections?");
|
||||
|
||||
if (nsyms > 0) {
|
||||
/* write out symbol command */
|
||||
fwritelong(LC_SYMTAB, machofp); /* cmd == LC_SYMTAB */
|
||||
fwritelong(MACHO_SYMCMD_SIZE, machofp); /* size of load command */
|
||||
fwritelong(offset, machofp); /* symbol table offset */
|
||||
fwritelong(nsyms, machofp); /* number of symbol
|
||||
** table entries */
|
||||
|
||||
offset += nsyms * MACHO_NLIST_SIZE;
|
||||
fwritelong(offset, machofp); /* string table offset */
|
||||
fwritelong(strslen, machofp); /* string table size */
|
||||
}
|
||||
|
||||
/* emit section data */
|
||||
if (seg_nsects > 0) {
|
||||
struct section *s2;
|
||||
char *rel_paddata ="\0\0\0";
|
||||
unsigned char fi, *p, *q, blk[4];
|
||||
long l;
|
||||
|
||||
for (s = sects; s != NULL; s = s->next) {
|
||||
if ((s->flags & SECTION_TYPE) == S_ZEROFILL)
|
||||
continue;
|
||||
|
||||
/* no padding needs to be done to the sections */
|
||||
|
||||
/* Like a.out Mach-O references things in the data or bss
|
||||
* sections by addresses which are actually relative to the
|
||||
* start of the _text_ section, in the _file_. See outaout.c
|
||||
* for more information. */
|
||||
saa_rewind(s->data);
|
||||
for (r = s->relocs; r != NULL; r = r->next) {
|
||||
saa_fread(s->data, r->addr, blk, (long)r->length << 1);
|
||||
p = q = blk;
|
||||
l = *p++;
|
||||
|
||||
/* get offset based on relocation type */
|
||||
if (r->length > 0) {
|
||||
l += ((long)*p++) << 8;
|
||||
|
||||
if (r->length == 2) {
|
||||
l += ((long)*p++) << 16;
|
||||
l += ((long)*p++) << 24;
|
||||
}
|
||||
}
|
||||
|
||||
/* add sizes of previous sections to current offset */
|
||||
for (s2 = sects, fi = 1;
|
||||
s2 != NULL && fi < r->snum;
|
||||
s2 = s2->next, fi++)
|
||||
if ((s2->flags & SECTION_TYPE) != S_ZEROFILL)
|
||||
l += s2->size;
|
||||
|
||||
/* write new offset back */
|
||||
if (r->length == 2)
|
||||
WRITELONG(q, l);
|
||||
else if (r->length == 1)
|
||||
WRITESHORT(q, l);
|
||||
else
|
||||
*q++ = l & 0xFF;
|
||||
|
||||
saa_fwrite(s->data, r->addr, blk, (long)r->length << 1);
|
||||
}
|
||||
|
||||
/* dump the section data to file */
|
||||
saa_fpwrite(s->data, machofp);
|
||||
}
|
||||
|
||||
/* pad last section up to reloc entries on long boundary */
|
||||
fwrite(rel_paddata, rel_padcnt, 1, machofp);
|
||||
|
||||
/* emit relocation entries */
|
||||
for (s = sects; s != NULL; s = s->next) {
|
||||
for (r = s->relocs; r != NULL; r = r->next) {
|
||||
unsigned long word2;
|
||||
|
||||
fwritelong(r->addr, machofp); /* reloc offset */
|
||||
|
||||
word2 = r->snum;
|
||||
word2 |= r->pcrel << 24;
|
||||
word2 |= r->length << 25;
|
||||
word2 |= r->ext << 27;
|
||||
word2 |= r->type << 28;
|
||||
fwritelong(word2, machofp); /* reloc data */
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* emit symbol table */
|
||||
if (nsyms > 0) {
|
||||
struct symbol *sym;
|
||||
long fi, i;
|
||||
|
||||
/* we don't need to pad here since MACHO_RELINFO_SIZE == 8 */
|
||||
|
||||
saa_rewind(syms);
|
||||
for (i = 0; i < nsyms; ++i) {
|
||||
sym = saa_rstruct(syms);
|
||||
|
||||
fwritelong(sym->strx, machofp); /* string table entry number */
|
||||
fwrite(&sym->type, 1, 1, machofp); /* symbol type */
|
||||
fwrite(&sym->sect, 1, 1, machofp); /* section */
|
||||
fwriteshort(sym->desc, machofp); /* description */
|
||||
|
||||
/* fix up the symbol value now we know the final section
|
||||
** sizes. */
|
||||
if (((sym->type & N_TYPE) == N_SECT) && (sym->sect != NO_SECT)) {
|
||||
for (s = sects, fi = 1;
|
||||
s != NULL && fi < sym->sect;
|
||||
s = s->next, ++fi)
|
||||
sym->value += s->size;
|
||||
}
|
||||
|
||||
fwritelong(sym->value, machofp); /* value (i.e. offset) */
|
||||
}
|
||||
}
|
||||
|
||||
/* we don't need to pad here since MACHO_NLIST_SIZE == 12 */
|
||||
|
||||
/* emit string table */
|
||||
saa_fpwrite(strs, machofp);
|
||||
|
||||
/* done - yay! */
|
||||
fclose(machofp);
|
||||
|
||||
/* free up everything */
|
||||
while (sects->next) {
|
||||
s = sects;
|
||||
sects = sects->next;
|
||||
|
||||
saa_free(s->data);
|
||||
while (s->relocs != NULL) {
|
||||
r = s->relocs;
|
||||
s->relocs = s->relocs->next;
|
||||
nasm_free(r);
|
||||
}
|
||||
|
||||
nasm_free(s);
|
||||
}
|
||||
|
||||
saa_free(strs);
|
||||
raa_free(extsyms);
|
||||
saa_free(syms);
|
||||
}
|
||||
|
||||
struct ofmt of_macho = {
|
||||
"NeXTstep/OpenStep/Rhapsody/Darwin/MacOS X object files",
|
||||
"macho",
|
||||
NULL,
|
||||
null_debug_arr,
|
||||
&null_debug_form,
|
||||
macho_stdmac,
|
||||
macho_init,
|
||||
macho_setinfo,
|
||||
macho_output,
|
||||
macho_symdef,
|
||||
macho_section,
|
||||
macho_segbase,
|
||||
macho_directive,
|
||||
macho_filename,
|
||||
macho_cleanup
|
||||
};
|
||||
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Local Variables:
|
||||
* mode:c
|
||||
* c-basic-offset:4
|
||||
* End:
|
||||
*
|
||||
* end of file */
|
||||
Loading…
Reference in New Issue
Block a user