static struct SAA *elf_build_reltab(long *len, struct Reloc *r)
{
struct SAA *s;
unsigned char *p, entry[8];
if (!r)
return NULL;
s = saa_init(1L);
*len = 0;
while (r) {
long sym = r->symbol;
if (sym >= GLOBAL_TEMP_BASE)
sym += -GLOBAL_TEMP_BASE + (nsects + 3) + nlocals;
p = entry;
WRITELONG(p, r->address);
WRITELONG(p, (sym << 8) + r->type);
saa_wbytes(s, entry, 8L);
*len += 8;
r = r->next;
}
return s;
}
/*
* Writes a string, *including* the final null, to the specified SAA,
* and return the number of bytes written.
*/
size_t saa_wcstring(struct SAA *s, const char *str)
{
size_t bytes = strlen(str) + 1;
saa_wbytes(s, str, bytes);
return bytes;
}
static void coff_deflabel (char *name, long segment, long offset,
int is_global, char *special)
{
int pos = strslen+4;
struct Symbol *sym;
if (special)
error (ERR_NONFATAL, "binary format does not support any"
" special symbol types");
if (name[0] == '.' && name[1] == '.' && name[2] != '@') {
error (ERR_NONFATAL, "unrecognised special symbol `%s'", name);
return;
}
if (strlen(name) > 8) {
saa_wbytes (strs, name, (long)(1+strlen(name)));
strslen += 1+strlen(name);
} else
pos = -1;
sym = saa_wstruct (syms);
sym->strpos = pos;
if (pos == -1)
strcpy (sym->name, name);
sym->is_global = !!is_global;
if (segment == NO_SEG)
sym->section = -1; /* absolute symbol */
else {
int i;
sym->section = 0;
for (i=0; i<nsects; i++)
if (segment == sects[i]->index) {
sym->section = i+1;
break;
}
if (!sym->section)
sym->is_global = TRUE;
}
if (is_global == 2)
sym->value = offset;
else
sym->value = (sym->section == 0 ? 0 : offset);
/*
* define the references from external-symbol segment numbers
* to these symbol records.
*/
if (sym->section == 0)
bsym = raa_write (bsym, segment, nsyms);
if (segment != NO_SEG)
symval = raa_write (symval, segment, sym->section ? 0 : sym->value);
nsyms++;
}
static int as86_add_string (char *name) {
int pos = strslen;
int length = strlen(name);
saa_wbytes (strs, name, (long)(length+1));
strslen += 1+length;
return pos;
}
static size_t as86_add_string(const char *name)
{
size_t pos = strslen;
size_t length = strlen(name);
saa_wbytes(strs, name, length + 1);
strslen += 1 + length;
return pos;
}
static void elf_init(FILE * fp, efunc errfunc, ldfunc ldef, evalfunc eval)
{
elffp = fp;
error = errfunc;
evaluate = eval;
(void)ldef; /* placate optimisers */
sects = NULL;
nsects = sectlen = 0;
syms = saa_init((long)sizeof(struct Symbol));
nlocals = nglobs = 0;
bsym = raa_init();
strs = saa_init(1L);
saa_wbytes(strs, "\0", 1L);
saa_wbytes(strs, elf_module, (long)(strlen(elf_module) + 1));
strslen = 2 + strlen(elf_module);
shstrtab = NULL;
shstrtablen = shstrtabsize = 0;;
add_sectname("", "");
fwds = NULL;
elf_gotpc_sect = seg_alloc();
ldef("..gotpc", elf_gotpc_sect + 1, 0L, NULL, FALSE, FALSE, &of_elf,
error);
elf_gotoff_sect = seg_alloc();
ldef("..gotoff", elf_gotoff_sect + 1, 0L, NULL, FALSE, FALSE, &of_elf,
error);
elf_got_sect = seg_alloc();
ldef("..got", elf_got_sect + 1, 0L, NULL, FALSE, FALSE, &of_elf,
error);
elf_plt_sect = seg_alloc();
ldef("..plt", elf_plt_sect + 1, 0L, NULL, FALSE, FALSE, &of_elf,
error);
elf_sym_sect = seg_alloc();
ldef("..sym", elf_sym_sect + 1, 0L, NULL, FALSE, FALSE, &of_elf,
error);
def_seg = seg_alloc();
}
static void elf_deflabel(char *name, long segment, long offset,
int is_global, char *special)
{
int pos = strslen;
struct Symbol *sym;
int special_used = FALSE;
#if defined(DEBUG) && DEBUG>2
fprintf(stderr,
" elf_deflabel: %s, seg=%ld, off=%ld, is_global=%d, %s\n",
name, segment, offset, is_global, special);
#endif
if (name[0] == '.' && name[1] == '.' && name[2] != '@') {
/*
* This is a NASM special symbol. We never allow it into
* the ELF 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 && !isspace(*p))
p++;
while (*p && 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, (long)(1 + strlen(name)));
strslen += 1 + strlen(name);
sym = saa_wstruct(syms);
sym->strpos = pos;
sym->type = is_global ? SYM_GLOBAL : 0;
sym->size = 0;
if (segment == NO_SEG)
sym->section = SHN_ABS;
else {
int i;
sym->section = SHN_UNDEF;
if (nsects == 0 && segment == def_seg) {
int tempint;
if (segment != elf_section_names(".text", 2, &tempint))
error(ERR_PANIC,
"strange segment conditions in ELF driver");
sym->section = nsects;
} else {
for (i = 0; i < nsects; i++)
if (segment == sects[i]->index) {
sym->section = i + 1;
break;
}
}
}
if (is_global == 2) {
sym->size = offset;
sym->value = 0;
sym->section = SHN_COMMON;
/*
* We have a common variable. Check the special text to see
* if it's a valid number and power of two; if so, store it
* as the alignment for the common variable.
*/
if (special) {
int err;
sym->value = readnum(special, &err);
if (err)
error(ERR_NONFATAL, "alignment constraint `%s' is not a"
" valid number", special);
else if ((sym->value | (sym->value - 1)) != 2 * sym->value - 1)
error(ERR_NONFATAL, "alignment constraint `%s' is not a"
" power of two", special);
}
special_used = TRUE;
} else
sym->value = (sym->section == SHN_UNDEF ? 0 : offset);
if (sym->type == SYM_GLOBAL) {
/*
* There's a problem here that needs fixing.
* If sym->section == SHN_ABS, then the first line of the
* else section causes a core dump, because its a reference
* beyond the end of the section array.
* This behaviour is exhibited by this code:
* GLOBAL crash_nasm
* crash_nasm equ 0
*
* I'm not sure how to procede, because I haven't got the
* first clue about how ELF works, so I don't know what to
* do with it. Furthermore, I'm not sure what the rest of this
* section of code does. Help?
*
* For now, I'll see if doing absolutely nothing with it will
* work...
*/
if (sym->section == SHN_UNDEF || sym->section == SHN_COMMON) {
bsym = raa_write(bsym, segment, nglobs);
} else if (sym->section != SHN_ABS) {
/*
* This is a global symbol; so we must add it to the linked
* list of global symbols in its section. We'll push it on
* the beginning of the list, because it doesn't matter
* much which end we put it on and it's easier like this.
*
* In addition, we check the special text for symbol
* type and size information.
*/
sym->next = sects[sym->section - 1]->gsyms;
sects[sym->section - 1]->gsyms = sym;
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 */
while (special[n] && isspace(special[n]))
n++;
/*
* We have a size expression; attempt to
* evaluate it.
*/
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;
}
}
sym->globnum = nglobs;
nglobs++;
} else
nlocals++;
if (special && !special_used)
error(ERR_NONFATAL, "no special symbol features supported here");
}
static void elf_sect_write(struct Section *sect,
const unsigned char *data, unsigned long len)
{
saa_wbytes(sect->data, data, len);
sect->len += len;
}
static struct SAA *elf_build_symtab(long *len, long *local)
{
struct SAA *s = saa_init(1L);
struct Symbol *sym;
unsigned char entry[16], *p;
int i;
*len = *local = 0;
/*
* First, an all-zeros entry, required by the ELF spec.
*/
saa_wbytes(s, NULL, 16L); /* null symbol table entry */
*len += 16;
(*local)++;
/*
* Next, an entry for the file name.
*/
p = entry;
WRITELONG(p, 1); /* we know it's 1st thing in strtab */
WRITELONG(p, 0); /* no value */
WRITELONG(p, 0); /* no size either */
WRITESHORT(p, 4); /* type FILE */
WRITESHORT(p, SHN_ABS);
saa_wbytes(s, entry, 16L);
*len += 16;
(*local)++;
/*
* Now some standard symbols defining the segments, for relocation
* purposes.
*/
for (i = 1; i <= nsects + 1; i++) {
p = entry;
WRITELONG(p, 0); /* no symbol name */
WRITELONG(p, 0); /* offset zero */
WRITELONG(p, 0); /* size zero */
WRITESHORT(p, 3); /* local section-type thing */
WRITESHORT(p, (i == 1 ? SHN_ABS : i - 1)); /* the section id */
saa_wbytes(s, entry, 16L);
*len += 16;
(*local)++;
}
/*
* Now the other local symbols.
*/
saa_rewind(syms);
while ((sym = saa_rstruct(syms))) {
if (sym->type & SYM_GLOBAL)
continue;
p = entry;
WRITELONG(p, sym->strpos);
WRITELONG(p, sym->value);
WRITELONG(p, sym->size);
WRITESHORT(p, sym->type); /* local non-typed thing */
WRITESHORT(p, sym->section);
saa_wbytes(s, entry, 16L);
*len += 16;
(*local)++;
}
/*
* Now the global symbols.
*/
saa_rewind(syms);
while ((sym = saa_rstruct(syms))) {
if (!(sym->type & SYM_GLOBAL))
continue;
p = entry;
WRITELONG(p, sym->strpos);
WRITELONG(p, sym->value);
WRITELONG(p, sym->size);
WRITESHORT(p, sym->type); /* global non-typed thing */
WRITESHORT(p, sym->section);
saa_wbytes(s, entry, 16L);
*len += 16;
}
return s;
}
static void aout_deflabel (char *name, long segment, long 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 && !isspace(*p)) p++;
while (*p && 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, (long)(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] && 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 as86_sect_write(struct Section *sect,
const uint8_t *data, uint32_t len)
{
saa_wbytes(sect->data, data, len);
sect->datalen += len;
}
static void as86_sect_write (struct Section *sect,
unsigned char *data, unsigned long len)
{
saa_wbytes (sect->data, data, len);
sect->datalen += len;
}
