void rdl_perror(const char *apname, const char *filename)
{
if (rdl_error >= 16)
rdfperror(apname, filename);
else
fprintf(stderr, "%s:%s:%s\n", apname, filename,
rdl_errors[rdl_error]);
}
void loadmodule(const char * filename)
{
if (options.verbose)
printf("loading `%s'\n", filename);
/* allocate a new module entry on the end of the modules list */
if (!modules)
{
modules = malloc (sizeof(*modules));
lastmodule = modules;
}
else
{
lastmodule->next = malloc (sizeof(*modules));
lastmodule = lastmodule->next;
}
if ( ! lastmodule)
{
fprintf(stderr, "ldrdf: out of memory\n");
exit(1);
}
/* open the file using 'rdfopen', which returns nonzero on error */
if (rdfopen(&lastmodule->f, filename) != 0)
{
rdfperror("ldrdf", filename);
exit(1);
}
/*
* store information about the module, and determine what segments
* it contains, and what we should do with them (determine relocation
* factor if we decide to keep them)
*/
lastmodule->header = NULL;
lastmodule->name = strdup(filename);
lastmodule->next = NULL;
processmodule(filename, lastmodule);
}
/*
* write_output()
*
* this takes the linked list of modules, and walks through it, merging
* all the modules into a single output module, and then writes this to a
* file.
*/
void write_output(const char *filename)
{
FILE *f;
rdf_headerbuf *rdfheader;
struct modulenode *cur;
int i, availableseg, seg, localseg, isrelative;
void *header;
rdfheaderrec *hr, newrec;
symtabEnt *se;
segtab segs;
long offset;
byte *data;
if ((f = fopen(filename, "wb")) == NULL) {
fprintf(stderr, "ldrdf: couldn't open %s for output\n", filename);
exit(1);
}
if ((rdfheader = rdfnewheader()) == NULL) {
fprintf(stderr, "ldrdf: out of memory\n");
exit(1);
}
/*
* If '-g' option was given, first record in output file will be a
* `generic' record, filled with a given file content.
* This can be useful, for example, when constructing multiboot
* compliant kernels.
*/
if (generic_rec_file) {
FILE *ff;
if (options.verbose)
printf("\nadding generic record from binary file %s\n",
generic_rec_file);
hr = (rdfheaderrec *) malloc(sizeof(struct GenericRec));
if ((ff = fopen(generic_rec_file, "r")) == NULL) {
fprintf(stderr, "ldrdf: couldn't open %s for input\n",
generic_rec_file);
exit(1);
}
i = fread(hr->g.data, 1, sizeof(hr->g.data), ff);
fseek(ff, 0, SEEK_END);
if (ftell(ff) > sizeof(hr->g.data)) {
fprintf(error_file,
"warning: maximum generic record size is %d, rest of file ignored\n",
sizeof(hr->g.data));
}
fclose(ff);
hr->g.type = 0;
hr->g.reclen = i;
rdfaddheader(rdfheader, hr);
free(hr);
}
if (options.verbose)
printf("\nbuilding output module (%d segments)\n", nsegs);
/*
* Allocate the memory for the segments. We may be better off
* building the output module one segment at a time when running
* under 16 bit DOS, but that would be a slower way of doing this.
* And you could always use DJGPP...
*/
for (i = 0; i < nsegs; i++) {
outputseg[i].data = NULL;
if (!outputseg[i].length)
continue;
outputseg[i].data = malloc(outputseg[i].length);
if (!outputseg[i].data) {
fprintf(stderr, "ldrdf: out of memory\n");
exit(1);
}
}
/*
* initialise availableseg, used to allocate segment numbers for
* imported and exported labels...
*/
availableseg = nsegs;
/*
* Step through the modules, performing required actions on each one
*/
for (cur = modules; cur; cur = cur->next) {
/*
* Read the actual segment contents into the correct places in
* the newly allocated segments
*/
for (i = 0; i < cur->f.nsegs; i++) {
int dest = cur->seginfo[i].dest_seg;
if (dest == -1)
continue;
if (rdfloadseg(&cur->f, i,
outputseg[dest].data + cur->seginfo[i].reloc)) {
rdfperror("ldrdf", cur->name);
exit(1);
}
}
/*
* Perform fixups, and add new header records where required
*/
header = malloc(cur->f.header_len);
if (!header) {
fprintf(stderr, "ldrdf: out of memory\n");
exit(1);
}
if (cur->f.header_loc)
rdfheaderrewind(&cur->f);
else if (rdfloadseg(&cur->f, RDOFF_HEADER, header)) {
rdfperror("ldrdf", cur->name);
exit(1);
}
/*
* we need to create a local segment number -> location
* table for the segments in this module.
*/
init_seglocations(&segs);
for (i = 0; i < cur->f.nsegs; i++) {
add_seglocation(&segs, cur->f.seg[i].number,
cur->seginfo[i].dest_seg,
cur->seginfo[i].reloc);
}
/*
* and the BSS segment (doh!)
*/
add_seglocation(&segs, 2, 2, cur->bss_reloc);
while ((hr = rdfgetheaderrec(&cur->f))) {
switch (hr->type) {
case RDFREC_RELOC: /* relocation record - need to do a fixup */
/*
* First correct the offset stored in the segment from
* the start of the segment (which may well have changed).
*
* To do this we add to the number stored the relocation
* factor associated with the segment that contains the
* target segment.
*
* The relocation could be a relative relocation, in which
* case we have to first subtract the amount we've relocated
* the containing segment by.
*/
if (!get_seglocation(&segs, hr->r.refseg, &seg, &offset)) {
fprintf(stderr,
"%s: reloc to undefined segment %04x\n",
cur->name, (int)hr->r.refseg);
errorcount++;
break;
}
isrelative =
(hr->r.segment & RDOFF_RELATIVEMASK) ==
RDOFF_RELATIVEMASK;
hr->r.segment &= (RDOFF_RELATIVEMASK - 1);
if (hr->r.segment == 2 ||
(localseg =
rdffindsegment(&cur->f, hr->r.segment)) == -1) {
fprintf(stderr, "%s: reloc from %s segment (%d)\n",
cur->name,
hr->r.segment == 2 ? "BSS" : "unknown",
hr->r.segment);
errorcount++;
break;
}
if (hr->r.length != 1 && hr->r.length != 2 &&
hr->r.length != 4) {
fprintf(stderr, "%s: nonstandard length reloc "
"(%d bytes)\n", cur->name, hr->r.length);
errorcount++;
break;
}
/*
* okay, now the relocation is in the segment pointed to by
* cur->seginfo[localseg], and we know everything else is
* okay to go ahead and do the relocation
*/
data = outputseg[cur->seginfo[localseg].dest_seg].data;
data += cur->seginfo[localseg].reloc + hr->r.offset;
/*
* data now points to the reference that needs
* relocation. Calculate the relocation factor.
* Factor is:
* offset of referred object in segment [in offset]
* (- relocation of localseg, if ref is relative)
* For simplicity, the result is stored in 'offset'.
* Then add 'offset' onto the value at data.
*/
if (isrelative)
offset -= cur->seginfo[localseg].reloc;
switch (hr->r.length) {
case 1:
offset += *data;
if (offset < -127 || offset > 128)
fprintf(error_file,
"warning: relocation out of range "
"at %s(%02x:%08lx)\n", cur->name,
(int)hr->r.segment, hr->r.offset);
*data = (char)offset;
break;
case 2:
offset += *(short *)data;
if (offset < -32767 || offset > 32768)
fprintf(error_file,
"warning: relocation out of range "
"at %s(%02x:%08lx)\n", cur->name,
(int)hr->r.segment, hr->r.offset);
*(short *)data = (short)offset;
break;
case 4:
*(long *)data += offset;
/* we can't easily detect overflow on this one */
break;
}
/*
* If the relocation was relative between two symbols in
* the same segment, then we're done.
*
* Otherwise, we need to output a new relocation record
* with the references updated segment and offset...
*/
if (!isrelative || cur->seginfo[localseg].dest_seg != seg) {
hr->r.segment = cur->seginfo[localseg].dest_seg;
hr->r.offset += cur->seginfo[localseg].reloc;
hr->r.refseg = seg;
if (isrelative)
hr->r.segment += RDOFF_RELATIVEMASK;
rdfaddheader(rdfheader, hr);
}
break;
case RDFREC_IMPORT: /* import symbol */
case RDFREC_FARIMPORT:
/*
* scan the global symbol table for the symbol
* and associate its location with the segment number
* for this module
*/
se = symtabFind(symtab, hr->i.label);
if (!se || se->segment == -1) {
if (!options.dynalink && !(hr->i.flags & SYM_IMPORT)) {
fprintf(error_file,
"error: unresolved reference to `%s'"
" in module `%s'\n", hr->i.label,
cur->name);
errorcount++;
}
/*
* we need to allocate a segment number for this
* symbol, and store it in the symbol table for
* future reference
*/
if (!se) {
se = malloc(sizeof(*se));
if (!se) {
fprintf(stderr, "ldrdf: out of memory\n");
exit(1);
}
se->name = strdup(hr->i.label);
se->flags = 0;
se->segment = availableseg++;
se->offset = 0;
symtabInsert(symtab, se);
} else {
se->segment = availableseg++;
se->offset = 0;
}
/*
* output a header record that imports it to the
* recently allocated segment number...
*/
newrec = *hr;
newrec.i.segment = se->segment;
rdfaddheader(rdfheader, &newrec);
}
add_seglocation(&segs, hr->i.segment, se->segment,
se->offset);
break;
case RDFREC_GLOBAL: /* export symbol */
/*
* need to insert an export for this symbol into the new
* header, unless we're stripping symbols. Even if we're
* stripping, put the symbol if it's marked as SYM_GLOBAL.
*/
if (options.strip && !(hr->e.flags & SYM_GLOBAL))
break;
if (hr->e.segment == 2) {
seg = 2;
offset = cur->bss_reloc;
} else {
localseg = rdffindsegment(&cur->f, hr->e.segment);
if (localseg == -1) {
fprintf(stderr, "%s: exported symbol `%s' from "
"unrecognised segment\n", cur->name,
hr->e.label);
errorcount++;
break;
}
offset = cur->seginfo[localseg].reloc;
seg = cur->seginfo[localseg].dest_seg;
}
hr->e.segment = seg;
hr->e.offset += offset;
rdfaddheader(rdfheader, hr);
break;
case RDFREC_MODNAME: /* module name */
/*
* Insert module name record if export symbols
* are not stripped.
* If module name begins with '$' - insert it anyway.
*/
if (options.strip && hr->m.modname[0] != '$')
break;
rdfaddheader(rdfheader, hr);
break;
case RDFREC_DLL: /* DLL name */
/*
* Insert DLL name if it begins with '$'
*/
if (hr->d.libname[0] != '$')
break;
rdfaddheader(rdfheader, hr);
break;
case RDFREC_SEGRELOC: /* segment fixup */
/*
* modify the segment numbers if necessary, and
* pass straight through to the output module header
*
* *** FIXME ***
*/
if (hr->r.segment == 2) {
fprintf(stderr, "%s: segment fixup in BSS section\n",
cur->name);
errorcount++;
break;
}
localseg = rdffindsegment(&cur->f, hr->r.segment);
if (localseg == -1) {
fprintf(stderr, "%s: segment fixup in unrecognised"
" segment (%d)\n", cur->name, hr->r.segment);
errorcount++;
break;
}
hr->r.segment = cur->seginfo[localseg].dest_seg;
hr->r.offset += cur->seginfo[localseg].reloc;
if (!get_seglocation(&segs, hr->r.refseg, &seg, &offset)) {
fprintf(stderr, "%s: segment fixup to undefined "
"segment %04x\n", cur->name,
(int)hr->r.refseg);
errorcount++;
break;
}
hr->r.refseg = seg;
rdfaddheader(rdfheader, hr);
break;
case RDFREC_COMMON: /* Common variable */
/* Is this symbol already in the table? */
se = symtabFind(symtab, hr->c.label);
if (!se) {
printf("%s is not in symtab yet\n", hr->c.label);
break;
}
/* Add segment location */
add_seglocation(&segs, hr->c.segment, se->segment,
se->offset);
break;
}
}
free(header);
done_seglocations(&segs);
}
/*
* combined BSS reservation for the entire results
*/
newrec.type = RDFREC_BSS;
newrec.b.reclen = 4;
newrec.b.amount = bss_length;
rdfaddheader(rdfheader, &newrec);
/*
* Write the header
*/
for (i = 0; i < nsegs; i++) {
if (i == 2)
continue;
rdfaddsegment(rdfheader, outputseg[i].length);
}
rdfwriteheader(f, rdfheader);
rdfdoneheader(rdfheader);
/*
* Step through the segments, one at a time, writing out into
* the output file
*/
for (i = 0; i < nsegs; i++) {
uint16 s;
long l;
if (i == 2)
continue;
s = translateshort(outputseg[i].type);
fwrite(&s, 2, 1, f);
s = translateshort(outputseg[i].number);
fwrite(&s, 2, 1, f);
s = translateshort(outputseg[i].reserved);
fwrite(&s, 2, 1, f);
l = translatelong(outputseg[i].length);
fwrite(&l, 4, 1, f);
fwrite(outputseg[i].data, outputseg[i].length, 1, f);
}
fwrite("\0\0\0\0\0\0\0\0\0\0", 10, 1, f);
}
/*
* search_libraries()
*
* scans through the list of libraries, attempting to match symbols
* defined in library modules against symbols that are referenced but
* not defined (segment = -1 in the symbol table)
*
* returns 1 if any extra library modules are included, indicating that
* another pass through the library list should be made (possibly).
*/
int search_libraries()
{
struct librarynode *cur;
rdffile f;
int i;
void *header;
int segment;
long offset;
int doneanything = 0, pass = 1, keepfile;
rdfheaderrec *hr;
cur = libraries;
while (cur) {
if (options.verbose > 2)
printf("scanning library `%s', pass %d...\n", cur->name, pass);
for (i = 0; rdl_openmodule(cur, i, &f) == 0; i++) {
if (pass == 2 && lookformodule(f.name))
continue;
if (options.verbose > 3)
printf(" looking in module `%s'\n", f.name);
header = malloc(f.header_len);
if (!header) {
fprintf(stderr, "ldrdf: not enough memory\n");
exit(1);
}
if (rdfloadseg(&f, RDOFF_HEADER, header)) {
rdfperror("ldrdf", f.name);
errorcount++;
return 0;
}
keepfile = 0;
while ((hr = rdfgetheaderrec(&f))) {
/* We're only interested in exports, so skip others */
if (hr->type != RDFREC_GLOBAL)
continue;
/*
* If the symbol is marked as SYM_GLOBAL, somebody will be
* definitely interested in it..
*/
if ((hr->e.flags & SYM_GLOBAL) == 0) {
/*
* otherwise the symbol is just public. Find it in
* the symbol table. If the symbol isn't defined, we
* aren't interested, so go on to the next.
* If it is defined as anything but -1, we're also not
* interested. But if it is defined as -1, insert this
* module into the list of modules to use, and go
* immediately on to the next module...
*/
if (!symtab_get(hr->e.label, &segment, &offset)
|| segment != -1)
continue;
}
doneanything = 1;
keepfile = 1;
/*
* as there are undefined symbols, we can assume that
* there are modules on the module list by the time
* we get here.
*/
lastmodule->next = malloc(sizeof(*lastmodule->next));
if (!lastmodule->next) {
fprintf(stderr, "ldrdf: not enough memory\n");
exit(1);
}
lastmodule = lastmodule->next;
memcpy(&lastmodule->f, &f, sizeof(f));
lastmodule->name = strdup(f.name);
lastmodule->next = NULL;
processmodule(f.name, lastmodule);
break;
}
if (!keepfile) {
free(f.name);
f.name = NULL;
f.fp = NULL;
}
}
if (rdl_error != 0 && rdl_error != RDL_ENOTFOUND)
rdl_perror("ldrdf", cur->name);
cur = cur->next;
if (cur == NULL && pass == 1) {
cur = libraries;
pass++;
}
}
return doneanything;
}
/*
* processmodule()
*
* step through each segment, determine what exactly we're doing with
* it, and if we intend to keep it, determine (a) which segment to
* put it in and (b) whereabouts in that segment it will end up.
* (b) is fairly easy, because we're now keeping track of how big each
* segment in our output file is...
*/
void processmodule(const char *filename, struct modulenode *mod)
{
struct segconfig sconf;
int seg, outseg;
void *header;
rdfheaderrec *hr;
long bssamount = 0;
int bss_was_referenced = 0;
for (seg = 0; seg < mod->f.nsegs; seg++) {
/*
* get the segment configuration for this type from the segment
* table. getsegconfig() is a macro, defined in ldsegs.h.
*/
getsegconfig(sconf, mod->f.seg[seg].type);
if (options.verbose > 1) {
printf("%s %04x [%04x:%10s] ", filename,
mod->f.seg[seg].number, mod->f.seg[seg].type,
sconf.typedesc);
}
/*
* sconf->dowhat tells us what to do with a segment of this type.
*/
switch (sconf.dowhat) {
case SEG_IGNORE:
/*
* Set destination segment to -1, to indicate that this segment
* should be ignored for the purpose of output, ie it is left
* out of the linked executable.
*/
mod->seginfo[seg].dest_seg = -1;
if (options.verbose > 1)
printf("IGNORED\n");
break;
case SEG_NEWSEG:
/*
* The configuration tells us to create a new segment for
* each occurrence of this segment type.
*/
outseg = allocnewseg(sconf.mergetype,
mod->f.seg[seg].reserved);
mod->seginfo[seg].dest_seg = outseg;
mod->seginfo[seg].reloc = 0;
outputseg[outseg].length = mod->f.seg[seg].length;
if (options.verbose > 1)
printf("=> %04x:%08lx (+%04lx)\n", outseg,
mod->seginfo[seg].reloc, mod->f.seg[seg].length);
break;
case SEG_MERGE:
/*
* The configuration tells us to merge the segment with
* a previously existing segment of type 'sconf.mergetype',
* if one exists. Otherwise a new segment is created.
* This is handled transparently by 'findsegment()'.
*/
outseg = findsegment(sconf.mergetype,
mod->f.seg[seg].reserved);
mod->seginfo[seg].dest_seg = outseg;
/*
* We need to add alignment to these segments.
*/
if (outputseg[outseg].length % options.align != 0)
outputseg[outseg].length +=
options.align -
(outputseg[outseg].length % options.align);
mod->seginfo[seg].reloc = outputseg[outseg].length;
outputseg[outseg].length += mod->f.seg[seg].length;
if (options.verbose > 1)
printf("=> %04x:%08lx (+%04lx)\n", outseg,
mod->seginfo[seg].reloc, mod->f.seg[seg].length);
}
}
/*
* extract symbols from the header, and dump them into the
* symbol table
*/
header = malloc(mod->f.header_len);
if (!header) {
fprintf(stderr, "ldrdf: not enough memory\n");
exit(1);
}
if (rdfloadseg(&mod->f, RDOFF_HEADER, header)) {
rdfperror("ldrdf", filename);
exit(1);
}
while ((hr = rdfgetheaderrec(&mod->f))) {
switch (hr->type) {
case RDFREC_IMPORT: /* imported symbol */
case RDFREC_FARIMPORT:
/* Define with seg = -1 */
symtab_add(hr->i.label, -1, 0);
break;
case RDFREC_GLOBAL:{ /* exported symbol */
int destseg;
long destreloc;
if (hr->e.segment == 2) {
bss_was_referenced = 1;
destreloc = bss_length;
if (destreloc % options.align != 0)
destreloc +=
options.align - (destreloc % options.align);
destseg = 2;
} else {
if ((destseg =
mod->seginfo[(int)hr->e.segment].dest_seg) == -1)
continue;
destreloc = mod->seginfo[(int)hr->e.segment].reloc;
}
symtab_add(hr->e.label, destseg, destreloc + hr->e.offset);
break;
}
case RDFREC_BSS: /* BSS reservation */
/*
* first, amalgamate all BSS reservations in this module
* into one, because we allow this in the output format.
*/
bssamount += hr->b.amount;
break;
case RDFREC_COMMON:{ /* Common variable */
symtabEnt *ste = symtabFind(symtab, hr->c.label);
/* Is the symbol already in the table? */
if (ste)
break;
/* Align the variable */
if (bss_length % hr->c.align != 0)
bss_length += hr->c.align - (bss_length % hr->c.align);
if (options.verbose > 1) {
printf("%s %04x common '%s' => 0002:%08lx (+%04lx)\n",
filename, hr->c.segment, hr->c.label,
bss_length, hr->c.size);
}
symtab_add(hr->c.label, 2, bss_length);
mod->bss_reloc = bss_length;
bss_length += hr->c.size;
break;
}
}
}
if (bssamount != 0 || bss_was_referenced) {
/*
* handle the BSS segment - first pad the existing bss length
* to the correct alignment, then store the length in bss_reloc
* for this module. Then add this module's BSS length onto
* bss_length.
*/
if (bss_length % options.align != 0)
bss_length += options.align - (bss_length % options.align);
mod->bss_reloc = bss_length;
if (options.verbose > 1) {
printf("%s 0002 [ BSS] => 0002:%08lx (+%04lx)\n",
filename, bss_length, bssamount);
}
bss_length += bssamount;
}
#ifdef STINGY_MEMORY
/*
* we free the header buffer here, to save memory later.
* this isn't efficient, but probably halves the memory usage
* of this program...
*/
mod->f.header_loc = NULL;
free(header);
#endif
}
/*
* write_output()
*
* this takes the linked list of modules, and walks through it, merging
* all the modules into a single output module, and then writes this to a
* file.
*/
void write_output(const char * filename)
{
FILE * f = fopen(filename, "wb");
rdf_headerbuf * rdfheader = rdfnewheader();
struct modulenode * cur;
int i, availableseg, seg, localseg, isrelative;
void * header;
rdfheaderrec * hr, newrec;
symtabEnt * se;
segtab segs;
long offset;
byte * data;
if (!f) {
fprintf(stderr, "ldrdf: couldn't open %s for output\n", filename);
exit(1);
}
if (!rdfheader) {
fprintf(stderr, "ldrdf: out of memory\n");
exit(1);
}
if (options.verbose)
printf ("\nbuilding output module (%d segments)\n", nsegs);
/*
* Allocate the memory for the segments. We may be better off
* building the output module one segment at a time when running
* under 16 bit DOS, but that would be a slower way of doing this.
* And you could always use DJGPP...
*/
for (i = 0; i < nsegs; i++)
{
outputseg[i].data = malloc(outputseg[i].length);
if (!outputseg[i].data) {
fprintf(stderr, "ldrdf: out of memory\n");
exit(1);
}
}
/*
* initialise availableseg, used to allocate segment numbers for
* imported and exported labels...
*/
availableseg = nsegs;
/*
* Step through the modules, performing required actions on each one
*/
for (cur = modules; cur; cur=cur->next)
{
/*
* Read the actual segment contents into the correct places in
* the newly allocated segments
*/
for (i = 0; i < cur->f.nsegs; i++)
{
int dest = cur->seginfo[i].dest_seg;
if (dest == -1) continue;
if (rdfloadseg(&cur->f, i,
outputseg[dest].data + cur->seginfo[i].reloc))
{
rdfperror("ldrdf", cur->name);
exit(1);
}
}
/*
* Perform fixups, and add new header records where required
*/
header = malloc(cur->f.header_len);
if (!header) {
fprintf(stderr, "ldrdf: out of memory\n");
exit(1);
}
if (cur->f.header_loc)
rdfheaderrewind(&cur->f);
else
if (rdfloadseg(&cur->f, RDOFF_HEADER, header))
{
rdfperror("ldrdf", cur->name);
exit(1);
}
/*
* we need to create a local segment number -> location
* table for the segments in this module.
*/
init_seglocations(&segs);
for (i = 0; i < cur->f.nsegs; i++)
{
add_seglocation(&segs, cur->f.seg[i].number,
cur->seginfo[i].dest_seg, cur->seginfo[i].reloc);
}
/*
* and the BSS segment (doh!)
*/
add_seglocation (&segs, 2, 2, cur->bss_reloc);
while ((hr = rdfgetheaderrec(&cur->f)))
{
switch(hr->type) {
case 1: /* relocation record - need to do a fixup */
/*
* First correct the offset stored in the segment from
* the start of the segment (which may well have changed).
*
* To do this we add to the number stored the relocation
* factor associated with the segment that contains the
* target segment.
*
* The relocation could be a relative relocation, in which
* case we have to first subtract the amount we've relocated
* the containing segment by.
*/
if (!get_seglocation(&segs, hr->r.refseg, &seg, &offset))
{
fprintf(stderr, "%s: reloc to undefined segment %04x\n",
cur->name, (int) hr->r.refseg);
errorcount++;
break;
}
isrelative = (hr->r.segment & 64) == 64;
hr->r.segment &= 63;
if (hr->r.segment == 2 ||
(localseg = rdffindsegment(&cur->f, hr->r.segment)) == -1)
{
fprintf(stderr, "%s: reloc from %s segment (%d)\n",
cur->name,
hr->r.segment == 2 ? "BSS" : "unknown",
hr->r.segment);
errorcount++;
break;
}
if (hr->r.length != 1 && hr->r.length != 2 && hr->r.length!=4)
{
fprintf(stderr, "%s: nonstandard length reloc "
"(%d bytes)\n", cur->name, hr->r.length);
errorcount++;
break;
}
/*
* okay, now the relocation is in the segment pointed to by
* cur->seginfo[localseg], and we know everything else is
* okay to go ahead and do the relocation
*/
data = outputseg[cur->seginfo[localseg].dest_seg].data;
data += cur->seginfo[localseg].reloc + hr->r.offset;
/*
* data now points to the reference that needs
* relocation. Calculate the relocation factor.
* Factor is:
* offset of referred object in segment [in offset]
* (- relocation of localseg, if ref is relative)
* For simplicity, the result is stored in 'offset'.
* Then add 'offset' onto the value at data.
*/
if (isrelative) offset -= cur->seginfo[localseg].reloc;
switch (hr->r.length)
{
case 1:
offset += *data;
if (offset < -127 || offset > 128)
fprintf(stderr, "warning: relocation out of range "
"at %s(%02x:%08lx)\n", cur->name,
(int)hr->r.segment, hr->r.offset);
*data = (char) offset;
break;
case 2:
offset += * (short *)data;
if (offset < -32767 || offset > 32768)
fprintf(stderr, "warning: relocation out of range "
"at %s(%02x:%08lx)\n", cur->name,
(int)hr->r.segment, hr->r.offset);
* (short *)data = (short) offset;
break;
case 4:
* (long *)data += offset;
/* we can't easily detect overflow on this one */
break;
}
/*
* If the relocation was relative between two symbols in
* the same segment, then we're done.
*
* Otherwise, we need to output a new relocation record
* with the references updated segment and offset...
*/
if (! isrelative
|| cur->seginfo[localseg].dest_seg != seg)
{
hr->r.segment = cur->seginfo[localseg].dest_seg;
hr->r.offset += cur->seginfo[localseg].reloc;
hr->r.refseg = seg;
rdfaddheader(rdfheader, hr);
}
break;
case 2: /* import symbol */
case 7:
/*
* scan the global symbol table for the symbol
* and associate its location with the segment number
* for this module
*/
se = symtabFind(symtab, hr->i.label);
if (!se || se->segment == -1) {
if (options.warnUnresolved) {
fprintf(stderr, "warning: unresolved reference to `%s'"
" in module `%s'\n", hr->i.label, cur->name);
}
/*
* we need to allocate a segment number for this
* symbol, and store it in the symbol table for
* future reference
*/
if (!se) {
se=malloc(sizeof(*se));
if (!se) {
fprintf(stderr, "ldrdf: out of memory\n");
exit(1);
}
se->name = strdup(hr->i.label);
se->flags = 0;
se->segment = availableseg++;
se->offset = 0;
symtabInsert(symtab, se);
}
else {
se->segment = availableseg++;
se->offset = 0;
}
/*
* output a header record that imports it to the
* recently allocated segment number...
*/
newrec = *hr;
newrec.i.segment = se->segment;
rdfaddheader(rdfheader, &newrec);
}
add_seglocation(&segs, hr->i.segment, se->segment, se->offset);
break;
case 3: /* export symbol */
/*
* need to insert an export for this symbol into the new
* header, unless we're stripping symbols [unless this
* symbol is in an explicit keep list]. *** FIXME ***
*/
if (options.strip)
break;
if (hr->e.segment == 2) {
seg = 2;
offset = cur->bss_reloc;
}
else {
localseg = rdffindsegment(&cur->f, hr->e.segment);
if (localseg == -1) {
fprintf(stderr, "%s: exported symbol `%s' from "
"unrecognised segment\n", cur->name,
hr->e.label);
errorcount++;
break;
}
offset = cur->seginfo[localseg].reloc;
seg = cur->seginfo[localseg].dest_seg;
}
hr->e.segment = seg;
hr->e.offset += offset;
rdfaddheader(rdfheader, hr);
break;
case 6: /* segment fixup */
/*
* modify the segment numbers if necessary, and
* pass straight through to the output module header
*
* *** FIXME ***
*/
if (hr->r.segment == 2) {
fprintf(stderr, "%s: segment fixup in BSS section\n",
cur->name);
errorcount++;
break;
}
localseg = rdffindsegment(&cur->f, hr->r.segment);
if (localseg == -1) {
fprintf(stderr, "%s: segment fixup in unrecognised"
" segment (%d)\n", cur->name, hr->r.segment);
errorcount++;
break;
}
hr->r.segment = cur->seginfo[localseg].dest_seg;
hr->r.offset += cur->seginfo[localseg].reloc;
if (!get_seglocation(&segs, hr->r.refseg, &seg, &offset))
{
fprintf(stderr, "%s: segment fixup to undefined "
"segment %04x\n", cur->name, (int)hr->r.refseg);
errorcount++;
break;
}
hr->r.refseg = seg;
rdfaddheader(rdfheader, hr);
break;
}
}
free(header);
done_seglocations(&segs);
}
/*
* combined BSS reservation for the entire results
*/
newrec.type = 5;
newrec.b.reclen = 4;
newrec.b.amount = bss_length;
rdfaddheader(rdfheader, &newrec);
/*
* Write the header
*/
for (i = 0; i < nsegs; i++)
{
if (i == 2) continue;
rdfaddsegment (rdfheader, outputseg[i].length);
}
rdfwriteheader(f, rdfheader);
rdfdoneheader(rdfheader);
/*
* Step through the segments, one at a time, writing out into
* the output file
*/
for (i = 0; i < nsegs; i++)
{
int16 s;
long l;
if (i == 2) continue;
s = translateshort(outputseg[i].type);
fwrite(&s, 2, 1, f);
s = translateshort(outputseg[i].number);
fwrite(&s, 2, 1, f);
s = translateshort(outputseg[i].reserved);
fwrite(&s, 2, 1, f);
l = translatelong(outputseg[i].length);
fwrite(&l, 4, 1, f);
fwrite(outputseg[i].data, outputseg[i].length, 1, f);
}
fwrite("\0\0\0\0\0\0\0\0\0\0", 10, 1, f);
}
