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nasm/output/outaout.c
H. Peter Anvin 0cba107579 Make it possible for outputs to be either text or binary 
Allow the backend to specify that an output format is either text or
binary.  For future uses, define this as a flag word so we can define
other flags in the future if it would make sense.

Currently, the ieee and dbg formats are text; all the others are
binary.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-07-05 14:45:12 -07:00

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/* ----------------------------------------------------------------------- *
*
* Copyright 1996-2009 The NASM Authors - All Rights Reserved
* See the file AUTHORS included with the NASM distribution for
* the specific copyright holders.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following
* conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* ----------------------------------------------------------------------- */
/*
* outaout.c output routines for the Netwide Assembler to produce
* Linux a.out object files
*/
#include "compiler.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <inttypes.h>
#include "nasm.h"
#include "nasmlib.h"
#include "saa.h"
#include "raa.h"
#include "stdscan.h"
#include "output/outform.h"
#include "output/outlib.h"
#if defined OF_AOUT || defined OF_AOUTB
#define RELTYPE_ABSOLUTE 0x00
#define RELTYPE_RELATIVE 0x01
#define RELTYPE_GOTPC 0x01 /* no explicit GOTPC in a.out */
#define RELTYPE_GOTOFF 0x10
#define RELTYPE_GOT 0x10 /* distinct from GOTOFF bcos sym not sect */
#define RELTYPE_PLT 0x21
#define RELTYPE_SYMFLAG 0x08
struct Reloc {
struct Reloc *next;
int32_t address; /* relative to _start_ of section */
int32_t symbol; /* symbol number or -ve section id */
int bytes; /* 2 or 4 */
int reltype; /* see above */
};
struct Symbol {
int32_t strpos; /* string table position of name */
int type; /* symbol type - see flags below */
int32_t value; /* address, or COMMON variable size */
int32_t size; /* size for data or function exports */
int32_t segment; /* back-reference used by gsym_reloc */
struct Symbol *next; /* list of globals in each section */
struct Symbol *nextfwd; /* list of unresolved-size symbols */
char *name; /* for unresolved-size symbols */
int32_t symnum; /* index into symbol table */
};
/*
* Section IDs - used in Reloc.symbol when negative, and in
* Symbol.type when positive.
*/
#define SECT_ABS 2 /* absolute value */
#define SECT_TEXT 4 /* text section */
#define SECT_DATA 6 /* data section */
#define SECT_BSS 8 /* bss section */
#define SECT_MASK 0xE /* mask out any of the above */
/*
* More flags used in Symbol.type.
*/
#define SYM_GLOBAL 1 /* it's a global symbol */
#define SYM_DATA 0x100 /* used for shared libs */
#define SYM_FUNCTION 0x200 /* used for shared libs */
#define SYM_WITH_SIZE 0x4000 /* not output; internal only */
/*
* Bit more explanation of symbol types: SECT_xxx denotes a local
* symbol. SECT_xxx|SYM_GLOBAL denotes a global symbol, defined in
* this module. Just SYM_GLOBAL, with zero value, denotes an
* external symbol referenced in this module. And just SYM_GLOBAL,
* but with a non-zero value, declares a C `common' variable, of
* size `value'.
*/
struct Section {
struct SAA *data;
uint32_t len, size, nrelocs;
int32_t index;
struct Reloc *head, **tail;
struct Symbol *gsyms, *asym;
};
static struct Section stext, sdata, sbss;
static struct SAA *syms;
static uint32_t nsyms;
static struct RAA *bsym;
static struct SAA *strs;
static uint32_t strslen;
static struct Symbol *fwds;
static FILE *aoutfp;
static efunc error;
static evalfunc evaluate;
static int bsd;
static int is_pic;
static void aout_write(void);
static void aout_write_relocs(struct Reloc *);
static void aout_write_syms(void);
static void aout_sect_write(struct Section *, const uint8_t *,
uint32_t);
static void aout_pad_sections(void);
static void aout_fixup_relocs(struct Section *);
/*
* Special section numbers which are used to define special
* symbols, which can be used with WRT to provide PIC relocation
* types.
*/
static int32_t aout_gotpc_sect, aout_gotoff_sect;
static int32_t aout_got_sect, aout_plt_sect;
static int32_t aout_sym_sect;
static void aoutg_init(FILE * fp, efunc errfunc, ldfunc ldef,
evalfunc eval)
{
aoutfp = fp;
error = errfunc;
evaluate = eval;
(void)ldef; /* placate optimisers */
stext.data = saa_init(1L);
stext.head = NULL;
stext.tail = &stext.head;
sdata.data = saa_init(1L);
sdata.head = NULL;
sdata.tail = &sdata.head;
stext.len = stext.size = sdata.len = sdata.size = sbss.len = 0;
stext.nrelocs = sdata.nrelocs = 0;
stext.gsyms = sdata.gsyms = sbss.gsyms = NULL;
stext.index = seg_alloc();
sdata.index = seg_alloc();
sbss.index = seg_alloc();
stext.asym = sdata.asym = sbss.asym = NULL;
syms = saa_init((int32_t)sizeof(struct Symbol));
nsyms = 0;
bsym = raa_init();
strs = saa_init(1L);
strslen = 0;
fwds = NULL;
}
#ifdef OF_AOUT
static void aout_init(FILE * fp, efunc errfunc, ldfunc ldef, evalfunc eval)
{
bsd = false;
aoutg_init(fp, errfunc, ldef, eval);
aout_gotpc_sect = aout_gotoff_sect = aout_got_sect =
aout_plt_sect = aout_sym_sect = NO_SEG;
}
#endif
#ifdef OF_AOUTB
extern struct ofmt of_aoutb;
static void aoutb_init(FILE * fp, efunc errfunc, ldfunc ldef,
evalfunc eval)
{
bsd = true;
aoutg_init(fp, errfunc, ldef, eval);
is_pic = 0x00; /* may become 0x40 */
aout_gotpc_sect = seg_alloc();
ldef("..gotpc", aout_gotpc_sect + 1, 0L, NULL, false, false, &of_aoutb,
error);
aout_gotoff_sect = seg_alloc();
ldef("..gotoff", aout_gotoff_sect + 1, 0L, NULL, false, false,
&of_aoutb, error);
aout_got_sect = seg_alloc();
ldef("..got", aout_got_sect + 1, 0L, NULL, false, false, &of_aoutb,
error);
aout_plt_sect = seg_alloc();
ldef("..plt", aout_plt_sect + 1, 0L, NULL, false, false, &of_aoutb,
error);
aout_sym_sect = seg_alloc();
ldef("..sym", aout_sym_sect + 1, 0L, NULL, false, false, &of_aoutb,
error);
}
#endif
static void aout_cleanup(int debuginfo)
{
struct Reloc *r;
(void)debuginfo;
aout_pad_sections();
aout_fixup_relocs(&stext);
aout_fixup_relocs(&sdata);
aout_write();
fclose(aoutfp);
saa_free(stext.data);
while (stext.head) {
r = stext.head;
stext.head = stext.head->next;
nasm_free(r);
}
saa_free(sdata.data);
while (sdata.head) {
r = sdata.head;
sdata.head = sdata.head->next;
nasm_free(r);
}
saa_free(syms);
raa_free(bsym);
saa_free(strs);
}
static int32_t aout_section_names(char *name, int pass, int *bits)
{
(void)pass;
/*
* Default to 32 bits.
*/
if (!name)
*bits = 32;
if (!name)
return stext.index;
if (!strcmp(name, ".text"))
return stext.index;
else if (!strcmp(name, ".data"))
return sdata.index;
else if (!strcmp(name, ".bss"))
return sbss.index;
else
return NO_SEG;
}
static void aout_deflabel(char *name, int32_t segment, int64_t offset,
int is_global, char *special)
{
int pos = strslen + 4;
struct Symbol *sym;
int special_used = false;
if (name[0] == '.' && name[1] == '.' && name[2] != '@') {
/*
* This is a NASM special symbol. We never allow it into
* the a.out symbol table, even if it's a valid one. If it
* _isn't_ a valid one, we should barf immediately.
*/
if (strcmp(name, "..gotpc") && strcmp(name, "..gotoff") &&
strcmp(name, "..got") && strcmp(name, "..plt") &&
strcmp(name, "..sym"))
error(ERR_NONFATAL, "unrecognised special symbol `%s'", name);
return;
}
if (is_global == 3) {
struct Symbol **s;
/*
* Fix up a forward-reference symbol size from the first
* pass.
*/
for (s = &fwds; *s; s = &(*s)->nextfwd)
if (!strcmp((*s)->name, name)) {
struct tokenval tokval;
expr *e;
char *p = special;
while (*p && !nasm_isspace(*p))
p++;
while (*p && nasm_isspace(*p))
p++;
stdscan_reset();
stdscan_bufptr = p;
tokval.t_type = TOKEN_INVALID;
e = evaluate(stdscan, NULL, &tokval, NULL, 1, error, NULL);
if (e) {
if (!is_simple(e))
error(ERR_NONFATAL, "cannot use relocatable"
" expression as symbol size");
else
(*s)->size = reloc_value(e);
}
/*
* Remove it from the list of unresolved sizes.
*/
nasm_free((*s)->name);
*s = (*s)->nextfwd;
return;
}
return; /* it wasn't an important one */
}
saa_wbytes(strs, name, (int32_t)(1 + strlen(name)));
strslen += 1 + strlen(name);
sym = saa_wstruct(syms);
sym->strpos = pos;
sym->type = is_global ? SYM_GLOBAL : 0;
sym->segment = segment;
if (segment == NO_SEG)
sym->type |= SECT_ABS;
else if (segment == stext.index) {
sym->type |= SECT_TEXT;
if (is_global) {
sym->next = stext.gsyms;
stext.gsyms = sym;
} else if (!stext.asym)
stext.asym = sym;
} else if (segment == sdata.index) {
sym->type |= SECT_DATA;
if (is_global) {
sym->next = sdata.gsyms;
sdata.gsyms = sym;
} else if (!sdata.asym)
sdata.asym = sym;
} else if (segment == sbss.index) {
sym->type |= SECT_BSS;
if (is_global) {
sym->next = sbss.gsyms;
sbss.gsyms = sym;
} else if (!sbss.asym)
sbss.asym = sym;
} else
sym->type = SYM_GLOBAL;
if (is_global == 2)
sym->value = offset;
else
sym->value = (sym->type == SYM_GLOBAL ? 0 : offset);
if (is_global && sym->type != SYM_GLOBAL) {
/*
* Global symbol exported _from_ this module. We must check
* the special text for type information.
*/
if (special) {
int n = strcspn(special, " ");
if (!nasm_strnicmp(special, "function", n))
sym->type |= SYM_FUNCTION;
else if (!nasm_strnicmp(special, "data", n) ||
!nasm_strnicmp(special, "object", n))
sym->type |= SYM_DATA;
else
error(ERR_NONFATAL, "unrecognised symbol type `%.*s'",
n, special);
if (special[n]) {
struct tokenval tokval;
expr *e;
int fwd = false;
char *saveme = stdscan_bufptr; /* bugfix? fbk 8/10/00 */
if (!bsd) {
error(ERR_NONFATAL, "Linux a.out does not support"
" symbol size information");
} else {
while (special[n] && nasm_isspace(special[n]))
n++;
/*
* We have a size expression; attempt to
* evaluate it.
*/
sym->type |= SYM_WITH_SIZE;
stdscan_reset();
stdscan_bufptr = special + n;
tokval.t_type = TOKEN_INVALID;
e = evaluate(stdscan, NULL, &tokval, &fwd, 0, error,
NULL);
if (fwd) {
sym->nextfwd = fwds;
fwds = sym;
sym->name = nasm_strdup(name);
} else if (e) {
if (!is_simple(e))
error(ERR_NONFATAL, "cannot use relocatable"
" expression as symbol size");
else
sym->size = reloc_value(e);
}
}
stdscan_bufptr = saveme; /* bugfix? fbk 8/10/00 */
}
special_used = true;
}
}
/*
* define the references from external-symbol segment numbers
* to these symbol records.
*/
if (segment != NO_SEG && segment != stext.index &&
segment != sdata.index && segment != sbss.index)
bsym = raa_write(bsym, segment, nsyms);
sym->symnum = nsyms;
nsyms++;
if (sym->type & SYM_WITH_SIZE)
nsyms++; /* and another for the size */
if (special && !special_used)
error(ERR_NONFATAL, "no special symbol features supported here");
}
static void aout_add_reloc(struct Section *sect, int32_t segment,
int reltype, int bytes)
{
struct Reloc *r;
r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
sect->tail = &r->next;
r->next = NULL;
r->address = sect->len;
r->symbol = (segment == NO_SEG ? -SECT_ABS :
segment == stext.index ? -SECT_TEXT :
segment == sdata.index ? -SECT_DATA :
segment == sbss.index ? -SECT_BSS :
raa_read(bsym, segment));
r->reltype = reltype;
if (r->symbol >= 0)
r->reltype |= RELTYPE_SYMFLAG;
r->bytes = bytes;
sect->nrelocs++;
}
/*
* This routine deals with ..got and ..sym relocations: the more
* complicated kinds. In shared-library writing, some relocations
* with respect to global symbols must refer to the precise symbol
* rather than referring to an offset from the base of the section
* _containing_ the symbol. Such relocations call to this routine,
* which searches the symbol list for the symbol in question.
*
* RELTYPE_GOT references require the _exact_ symbol address to be
* used; RELTYPE_ABSOLUTE references can be at an offset from the
* symbol. The boolean argument `exact' tells us this.
*
* Return value is the adjusted value of `addr', having become an
* offset from the symbol rather than the section. Should always be
* zero when returning from an exact call.
*
* Limitation: if you define two symbols at the same place,
* confusion will occur.
*
* Inefficiency: we search, currently, using a linked list which
* isn't even necessarily sorted.
*/
static int32_t aout_add_gsym_reloc(struct Section *sect,
int32_t segment, int32_t offset,
int type, int bytes, int exact)
{
struct Symbol *sym, *sm, *shead;
struct Reloc *r;
/*
* First look up the segment to find whether it's text, data,
* bss or an external symbol.
*/
shead = NULL;
if (segment == stext.index)
shead = stext.gsyms;
else if (segment == sdata.index)
shead = sdata.gsyms;
else if (segment == sbss.index)
shead = sbss.gsyms;
if (!shead) {
if (exact && offset != 0)
error(ERR_NONFATAL, "unable to find a suitable global symbol"
" for this reference");
else
aout_add_reloc(sect, segment, type, bytes);
return offset;
}
if (exact) {
/*
* Find a symbol pointing _exactly_ at this one.
*/
for (sym = shead; sym; sym = sym->next)
if (sym->value == offset)
break;
} else {
/*
* Find the nearest symbol below this one.
*/
sym = NULL;
for (sm = shead; sm; sm = sm->next)
if (sm->value <= offset && (!sym || sm->value > sym->value))
sym = sm;
}
if (!sym && exact) {
error(ERR_NONFATAL, "unable to find a suitable global symbol"
" for this reference");
return 0;
}
r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
sect->tail = &r->next;
r->next = NULL;
r->address = sect->len;
r->symbol = sym->symnum;
r->reltype = type | RELTYPE_SYMFLAG;
r->bytes = bytes;
sect->nrelocs++;
return offset - sym->value;
}
/*
* This routine deals with ..gotoff relocations. These _must_ refer
* to a symbol, due to a perversity of *BSD's PIC implementation,
* and it must be a non-global one as well; so we store `asym', the
* first nonglobal symbol defined in each section, and always work
* from that. Relocation type is always RELTYPE_GOTOFF.
*
* Return value is the adjusted value of `addr', having become an
* offset from the `asym' symbol rather than the section.
*/
static int32_t aout_add_gotoff_reloc(struct Section *sect, int32_t segment,
int32_t offset, int bytes)
{
struct Reloc *r;
struct Symbol *asym;
/*
* First look up the segment to find whether it's text, data,
* bss or an external symbol.
*/
asym = NULL;
if (segment == stext.index)
asym = stext.asym;
else if (segment == sdata.index)
asym = sdata.asym;
else if (segment == sbss.index)
asym = sbss.asym;
if (!asym)
error(ERR_NONFATAL, "`..gotoff' relocations require a non-global"
" symbol in the section");
r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
sect->tail = &r->next;
r->next = NULL;
r->address = sect->len;
r->symbol = asym->symnum;
r->reltype = RELTYPE_GOTOFF;
r->bytes = bytes;
sect->nrelocs++;
return offset - asym->value;
}
static void aout_out(int32_t segto, const void *data,
enum out_type type, uint64_t size,
int32_t segment, int32_t wrt)
{
struct Section *s;
int32_t addr;
uint8_t mydata[4], *p;
/*
* handle absolute-assembly (structure definitions)
*/
if (segto == NO_SEG) {
if (type != OUT_RESERVE)
error(ERR_NONFATAL, "attempt to assemble code in [ABSOLUTE]"
" space");
return;
}
if (segto == stext.index)
s = &stext;
else if (segto == sdata.index)
s = &sdata;
else if (segto == sbss.index)
s = NULL;
else {
error(ERR_WARNING, "attempt to assemble code in"
" segment %d: defaulting to `.text'", segto);
s = &stext;
}
if (!s && type != OUT_RESERVE) {
error(ERR_WARNING, "attempt to initialize memory in the"
" BSS section: ignored");
sbss.len += realsize(type, size);
return;
}
if (type == OUT_RESERVE) {
if (s) {
error(ERR_WARNING, "uninitialized space declared in"
" %s section: zeroing",
(segto == stext.index ? "code" : "data"));
aout_sect_write(s, NULL, size);
} else
sbss.len += size;
} else if (type == OUT_RAWDATA) {
if (segment != NO_SEG)
error(ERR_PANIC, "OUT_RAWDATA with other than NO_SEG");
aout_sect_write(s, data, size);
} else if (type == OUT_ADDRESS) {
addr = *(int64_t *)data;
if (segment != NO_SEG) {
if (segment % 2) {
error(ERR_NONFATAL, "a.out format does not support"
" segment base references");
} else {
if (wrt == NO_SEG) {
aout_add_reloc(s, segment, RELTYPE_ABSOLUTE,
size);
} else if (!bsd) {
error(ERR_NONFATAL,
"Linux a.out format does not support"
" any use of WRT");
wrt = NO_SEG; /* we can at least _try_ to continue */
} else if (wrt == aout_gotpc_sect + 1) {
is_pic = 0x40;
aout_add_reloc(s, segment, RELTYPE_GOTPC, size);
} else if (wrt == aout_gotoff_sect + 1) {
is_pic = 0x40;
addr = aout_add_gotoff_reloc(s, segment,
addr, size);
} else if (wrt == aout_got_sect + 1) {
is_pic = 0x40;
addr =
aout_add_gsym_reloc(s, segment, addr, RELTYPE_GOT,
size, true);
} else if (wrt == aout_sym_sect + 1) {
addr = aout_add_gsym_reloc(s, segment, addr,
RELTYPE_ABSOLUTE, size,
false);
} else if (wrt == aout_plt_sect + 1) {
is_pic = 0x40;
error(ERR_NONFATAL,
"a.out format cannot produce non-PC-"
"relative PLT references");
} else {
error(ERR_NONFATAL,
"a.out format does not support this"
" use of WRT");
wrt = NO_SEG; /* we can at least _try_ to continue */
}
}
}
p = mydata;
if (size == 2)
WRITESHORT(p, addr);
else
WRITELONG(p, addr);
aout_sect_write(s, mydata, size);
} else if (type == OUT_REL2ADR) {
if (segment == segto)
error(ERR_PANIC, "intra-segment OUT_REL2ADR");
if (segment != NO_SEG && segment % 2) {
error(ERR_NONFATAL, "a.out format does not support"
" segment base references");
} else {
if (wrt == NO_SEG) {
aout_add_reloc(s, segment, RELTYPE_RELATIVE, 2);
} else if (!bsd) {
error(ERR_NONFATAL, "Linux a.out format does not support"
" any use of WRT");
wrt = NO_SEG; /* we can at least _try_ to continue */
} else if (wrt == aout_plt_sect + 1) {
is_pic = 0x40;
aout_add_reloc(s, segment, RELTYPE_PLT, 2);
} else if (wrt == aout_gotpc_sect + 1 ||
wrt == aout_gotoff_sect + 1 ||
wrt == aout_got_sect + 1) {
error(ERR_NONFATAL, "a.out format cannot produce PC-"
"relative GOT references");
} else {
error(ERR_NONFATAL, "a.out format does not support this"
" use of WRT");
wrt = NO_SEG; /* we can at least _try_ to continue */
}
}
p = mydata;
WRITESHORT(p, *(int64_t *)data - (size + s->len));
aout_sect_write(s, mydata, 2L);
} else if (type == OUT_REL4ADR) {
if (segment == segto)
error(ERR_PANIC, "intra-segment OUT_REL4ADR");
if (segment != NO_SEG && segment % 2) {
error(ERR_NONFATAL, "a.out format does not support"
" segment base references");
} else {
if (wrt == NO_SEG) {
aout_add_reloc(s, segment, RELTYPE_RELATIVE, 4);
} else if (!bsd) {
error(ERR_NONFATAL, "Linux a.out format does not support"
" any use of WRT");
wrt = NO_SEG; /* we can at least _try_ to continue */
} else if (wrt == aout_plt_sect + 1) {
is_pic = 0x40;
aout_add_reloc(s, segment, RELTYPE_PLT, 4);
} else if (wrt == aout_gotpc_sect + 1 ||
wrt == aout_gotoff_sect + 1 ||
wrt == aout_got_sect + 1) {
error(ERR_NONFATAL, "a.out format cannot produce PC-"
"relative GOT references");
} else {
error(ERR_NONFATAL, "a.out format does not support this"
" use of WRT");
wrt = NO_SEG; /* we can at least _try_ to continue */
}
}
p = mydata;
WRITELONG(p, *(int64_t *)data - (size + s->len));
aout_sect_write(s, mydata, 4L);
}
}
static void aout_pad_sections(void)
{
static uint8_t pad[] = { 0x90, 0x90, 0x90, 0x90 };
/*
* Pad each of the text and data sections with NOPs until their
* length is a multiple of four. (NOP == 0x90.) Also increase
* the length of the BSS section similarly.
*/
aout_sect_write(&stext, pad, (-(int32_t)stext.len) & 3);
aout_sect_write(&sdata, pad, (-(int32_t)sdata.len) & 3);
sbss.len = (sbss.len + 3) & ~3;
}
/*
* a.out files have the curious property that all references to
* things in the data or bss sections are done by addresses which
* are actually relative to the start of the _text_ section, in the
* _file_. (No relation to what happens after linking. No idea why
* this should be so. It's very strange.) So we have to go through
* the relocation table, _after_ the final size of each section is
* known, and fix up the relocations pointed to.
*/
static void aout_fixup_relocs(struct Section *sect)
{
struct Reloc *r;
saa_rewind(sect->data);
for (r = sect->head; r; r = r->next) {
uint8_t *p, *q, blk[4];
int32_t l;
saa_fread(sect->data, r->address, blk, (int32_t)r->bytes);
p = q = blk;
l = *p++;
if (r->bytes > 1) {
l += ((int32_t)*p++) << 8;
if (r->bytes == 4) {
l += ((int32_t)*p++) << 16;
l += ((int32_t)*p++) << 24;
}
}
if (r->symbol == -SECT_DATA)
l += stext.len;
else if (r->symbol == -SECT_BSS)
l += stext.len + sdata.len;
if (r->bytes == 4)
WRITELONG(q, l);
else if (r->bytes == 2)
WRITESHORT(q, l);
else
*q++ = l & 0xFF;
saa_fwrite(sect->data, r->address, blk, (int32_t)r->bytes);
}
}
static void aout_write(void)
{
/*
* Emit the a.out header.
*/
/* OMAGIC, M_386 or MID_I386, no flags */
fwriteint32_t(bsd ? 0x07018600 | is_pic : 0x640107L, aoutfp);
fwriteint32_t(stext.len, aoutfp);
fwriteint32_t(sdata.len, aoutfp);
fwriteint32_t(sbss.len, aoutfp);
fwriteint32_t(nsyms * 12, aoutfp); /* length of symbol table */
fwriteint32_t(0L, aoutfp); /* object files have no entry point */
fwriteint32_t(stext.nrelocs * 8, aoutfp); /* size of text relocs */
fwriteint32_t(sdata.nrelocs * 8, aoutfp); /* size of data relocs */
/*
* Write out the code section and the data section.
*/
saa_fpwrite(stext.data, aoutfp);
saa_fpwrite(sdata.data, aoutfp);
/*
* Write out the relocations.
*/
aout_write_relocs(stext.head);
aout_write_relocs(sdata.head);
/*
* Write the symbol table.
*/
aout_write_syms();
/*
* And the string table.
*/
fwriteint32_t(strslen + 4, aoutfp); /* length includes length count */
saa_fpwrite(strs, aoutfp);
}
static void aout_write_relocs(struct Reloc *r)
{
while (r) {
uint32_t word2;
fwriteint32_t(r->address, aoutfp);
if (r->symbol >= 0)
word2 = r->symbol;
else
word2 = -r->symbol;
word2 |= r->reltype << 24;
word2 |= (r->bytes == 1 ? 0 :
r->bytes == 2 ? 0x2000000L : 0x4000000L);
fwriteint32_t(word2, aoutfp);
r = r->next;
}
}
static void aout_write_syms(void)
{
uint32_t i;
saa_rewind(syms);
for (i = 0; i < nsyms; i++) {
struct Symbol *sym = saa_rstruct(syms);
fwriteint32_t(sym->strpos, aoutfp);
fwriteint32_t((int32_t)sym->type & ~SYM_WITH_SIZE, aoutfp);
/*
* Fix up the symbol value now we know the final section
* sizes.
*/
if ((sym->type & SECT_MASK) == SECT_DATA)
sym->value += stext.len;
if ((sym->type & SECT_MASK) == SECT_BSS)
sym->value += stext.len + sdata.len;
fwriteint32_t(sym->value, aoutfp);
/*
* Output a size record if necessary.
*/
if (sym->type & SYM_WITH_SIZE) {
fwriteint32_t(sym->strpos, aoutfp);
fwriteint32_t(0x0DL, aoutfp); /* special value: means size */
fwriteint32_t(sym->size, aoutfp);
i++; /* use up another of `nsyms' */
}
}
}
static void aout_sect_write(struct Section *sect,
const uint8_t *data, uint32_t len)
{
saa_wbytes(sect->data, data, len);
sect->len += len;
}
static int32_t aout_segbase(int32_t segment)
{
return segment;
}
static int aout_directive(char *directive, char *value, int pass)
{
(void)directive;
(void)value;
(void)pass;
return 0;
}
static void aout_filename(char *inname, char *outname, efunc error)
{
standard_extension(inname, outname, ".o", error);
}
extern macros_t aout_stdmac[];
static int aout_set_info(enum geninfo type, char **val)
{
(void)type;
(void)val;
return 0;
}
#endif /* OF_AOUT || OF_AOUTB */
#ifdef OF_AOUT
struct ofmt of_aout = {
"Linux a.out object files",
"aout",
0,
null_debug_arr,
&null_debug_form,
aout_stdmac,
aout_init,
aout_set_info,
aout_out,
aout_deflabel,
aout_section_names,
aout_segbase,
aout_directive,
aout_filename,
aout_cleanup
};
#endif
#ifdef OF_AOUTB
struct ofmt of_aoutb = {
"NetBSD/FreeBSD a.out object files",
"aoutb",
0,
null_debug_arr,
&null_debug_form,
aout_stdmac,
aoutb_init,
aout_set_info,
aout_out,
aout_deflabel,
aout_section_names,
aout_segbase,
aout_directive,
aout_filename,
aout_cleanup
};
#endif
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