NetBoot/vasm-1/vobjdump.c
2020-06-20 09:33:04 +08:00

421 lines
9.9 KiB
C

/*
* vobjdump
* Views the contents of a VOBJ file.
* Written by Frank Wille <frank@phoenix.owl.de>.
*/
/*
VOBJ Format (WILL CHANGE!):
.byte 0x56,0x4f,0x42,0x4a
.byte flags
1: BIGENDIAN
2: LITTLENDIAN
.number bitsperbyte
.number bytespertaddr
.string cpu
.number nsections [1-based]
.number nsymbols [1-based]
nsymbols
.string name
.number type
.number flags
.number secindex
.number val
.number size
nsections
.string name
.string attr
.number flags
.number align
.number size
.number nrelocs
.number databytes
.byte[databytes]
nrelocs [standard|special]
standard
.number type
.number byteoffset
.number bitoffset
.number size
.number mask
.number addend
.number symbolindex | 0 (sectionbase)
special
.number type
.number size
.byte[size]
.number:[taddr]
.byte 0--127 [0--127]
.byte 128-255 [x-0x80 bytes little-endian]
*/
#include "vobjdump.h"
static const char *endian_name[] = { "big", "little" };
static const char emptystr[] = "";
static const char sstr[] = "s";
static const char *reloc_name[] = {
"NONE","ABS","PC","GOT","GOTPC","GOTOFF","GLOBDAT","PLT","PLTPC","PLTOFF",
"SD","UABS","LOCALPC","LOADREL","COPY","JMPSLOT","SECOFF",NULL
};
static const char *type_name[] = {
"","obj","func","sect","file",NULL
};
static ubyte *vobj; /* base address of VOBJ buffer */
static size_t vlen; /* length of VOBJ file in buffer */
static ubyte *p; /* current object pointer */
static int bpb,bpt; /* bits per byte, bytes per taddr */
static taddr bptmask; /* mask LSB to fit bytes per taddr */
#define BPTMASK(x) (unsigned long long)((x)&bptmask)
static void print_sep(void)
{
printf("\n------------------------------------------------------------"
"------------------\n");
}
static taddr read_number(int is_signed)
{
taddr val;
ubyte n,*q;
int size;
if (p<vobj || p>=vobj+vlen) {
corrupt:
fprintf(stderr,"\nObject file is corrupt! Aborting.\n");
exit(1);
}
if ((n = *p++) <= 0x7f)
return (taddr)n;
val = 0;
if (n -= 0x80) {
size = n << 3;
p += n;
q = p;
if (p > vobj+vlen)
goto corrupt;
while (n--)
val = (val<<8) | *(--q);
if (is_signed && (val & (1LL<<(size-1))))
val |= ~makemask(size);
}
return val;
}
static void skip_string(void)
{
if (p < vobj)
goto corrupt;
while (*p) {
p++;
if (p >= vobj+vlen) {
corrupt:
fprintf(stderr,"\nObject file is corrupt! Aborting.\n");
exit(1);
}
}
p++;
}
static void read_symbol(struct vobj_symbol *vsym)
{
vsym->offs = p - vobj;
vsym->name = (const char *)p;
skip_string();
vsym->type = (int)read_number(0);
vsym->flags = (int)read_number(0);
vsym->sec = (int)read_number(0);
vsym->val = read_number(1);
vsym->size = (int)read_number(0);
}
static void read_section(struct vobj_section *vsect,
struct vobj_symbol *vsym,int nsyms)
{
const char *attr;
unsigned long flags;
int align,nrelocs,i;
vsect->offs = p - vobj;
vsect->name = p;
skip_string();
attr = p;
skip_string();
flags = (unsigned long)read_number(0);
align = (int)read_number(0);
vsect->dsize = read_number(0);
nrelocs = (int)read_number(0);
vsect->fsize = read_number(0);
print_sep();
printf("%08llx: SECTION \"%s\" (attributes=\"%s\")\n"
"Flags: %-8lx Alignment: %-6d "
"Total size: %-9lld File size: %-9lld\n",
BPTMASK(vsect->offs),vsect->name,attr,flags,align,
vsect->dsize,vsect->fsize);
if (nrelocs)
printf("%d Relocation%s present.\n",nrelocs,nrelocs==1?emptystr:sstr);
p += vsect->fsize; /* skip section contents */
/* read and print relocations for this section */
for (i=0; i<nrelocs; i++) {
ubyte type;
if (i == 0) {
/* print header */
printf("\nfile offs sectoffs pos sz mask type symbol+addend\n");
}
printf("%08llx: ",BPTMASK(p-vobj));
type = (ubyte)read_number(0);
if (type<sizeof(reloc_name)/sizeof(reloc_name[0])) {
/* standard relocation */
taddr offs,mask,addend;
int bpos,bsiz,sym;
const char *basesym;
offs = read_number(0);
bpos = (int)read_number(0);
bsiz = (int)read_number(0);
mask = read_number(1);
addend = read_number(1);
sym = (int)read_number(0) - 1; /* symbol index */
if (offs<0 || offs+(bpos>>3)>=vsect->dsize) {
printf("offset 0x%llx is outside of section!\n",
BPTMASK(offs+(bpos>>3)));
continue;
}
if (sym<0 || sym>=nsyms) {
printf("symbol index %d is illegal!\n",sym+1);
continue;
}
if (bsiz<0 || bsiz>bpt*bpb) {
printf("size of %d bits is illegal!\n",bsiz);
continue;
}
if (bpos<0 || bpos+bsiz>bpt*bpb) {
printf("bit field start=%d, size=%d doesn't fit into target address "
"type (%d bits)!\n",bpos,bsiz,bpt*bpb);
continue;
}
basesym = vsym[sym].name;
if (!strncmp(basesym," *current pc",12)) {
basesym = vsect->name;
/*addend += offs;*/
}
printf("%08llx %02d %02d %8llx %-8s %s%+lld\n",
BPTMASK(offs),bpos,bsiz,BPTMASK(mask),
reloc_name[type],basesym,addend);
}
else {
/* non-standard relocation */
taddr rsize;
rsize = read_number(0); /* size of special relocation entry */
if (rsize < 0) {
printf("Bad special relocation size (%d)!\n",(int)rsize);
exit(1);
}
p += rsize;
if (p<vobj || p>vobj+vlen)
break;
printf("special relocation type %-3d with a size of %d bytes\n",
(int)type,(int)rsize);
}
}
if (p<vobj || p>vobj+vlen) {
fprintf(stderr,"\nSection \"%s\" is corrupt! Aborting.\n",vsect->name);
exit(1);
}
}
static const char *bind_name(int flags)
{
if (flags & WEAK)
return "WEAK";
if (flags & EXPORT)
return "GLOB";
if (flags & COMMON)
return "COMM";
return "LOCL";
}
static const char *def_name(struct vobj_symbol *vs,
struct vobj_section *sec,int nsecs)
{
switch (vs->type) {
case EXPRESSION:
return "*ABS*";
case IMPORT:
return "*UND*";
case LABSYM:
if (vs->sec>0 && vs->sec<=nsecs)
return sec[vs->sec-1].name;
}
return "???";
}
static int vobjdump(void)
{
p = vobj;
if (vlen>4 && p[0]==0x56 && p[1]==0x4f && p[2]==0x42 && p[3]==0x4a) {
int endian,nsecs,nsyms,i;
const char *cpu_name;
struct vobj_symbol *vsymbols = NULL;
struct vobj_section *vsect = NULL;
p += 4; /* skip ID */
endian = (int)*p++; /* endianess */
if (endian<1 || endian>2) {
fprintf(stderr,"Wrong endianess: %d\n",endian);
return 1;
}
bpb = (int)read_number(0); /* bits per byte */
if (bpb != 8) {
fprintf(stderr,"%d bits per byte not supported!\n",bpb);
return 1;
}
bpt = (int)read_number(0); /* bytes per taddr */
if (bpt > sizeof(taddr)) {
fprintf(stderr,"%d bytes per taddr not supported!\n",bpt);
return 1;
}
bptmask = makemask(bpt*bpb);
cpu_name = p;
skip_string(); /* skip cpu-string */
nsecs = (int)read_number(0); /* number of sections */
nsyms = (int)read_number(0); /* number of symbols */
/* print header */
print_sep();
printf("VOBJ %s (%s endian), %d bits per byte, %d bytes per word.\n"
"%d symbol%s.\n%d section%s.\n",
cpu_name,endian_name[endian-1],bpb,bpt,
nsyms,nsyms==1?emptystr:sstr,nsecs,nsecs==1?emptystr:sstr);
/* read symbols */
if (nsyms) {
if (vsymbols = malloc(nsyms * sizeof(struct vobj_symbol))) {
for (i=0; i<nsyms; i++)
read_symbol(&vsymbols[i]);
}
else {
fprintf(stderr,"Cannot allocate %ld bytes for symbols!\n",
(long)(nsyms * sizeof(struct vobj_symbol)));
return 1;
}
}
/* read and print sections */
if (vsect = malloc(nsecs * sizeof(struct vobj_section))) {
for (i=0; i<nsecs; i++)
read_section(&vsect[i],vsymbols,nsyms);
}
else {
fprintf(stderr,"Cannot allocate %ld bytes for sections!\n",
(long)(nsecs * sizeof(struct vobj_section)));
return 1;
}
/* print symbols */
for (i=0; i<nsyms; i++) {
struct vobj_symbol *vs = &vsymbols[i];
if (i == 0) {
printf("\n");
print_sep();
printf("SYMBOL TABLE\n"
"file offs bind size type def value name\n");
}
if (!strncmp(vs->name," *current pc",12))
continue;
printf("%08llx: %-4s %08x %-4s %8.8s %8llx %s\n",
BPTMASK(vs->offs),bind_name(vs->flags),(unsigned)vs->size,
type_name[TYPE(vs)],def_name(vs,vsect,nsecs),
BPTMASK(vs->val),vs->name);
}
}
else {
fprintf(stderr,"Not a VOBJ file!\n");
return 1;
}
return 0;
}
static size_t filesize(FILE *fp,const char *name)
{
long oldpos,size;
if ((oldpos = ftell(fp)) >= 0)
if (fseek(fp,0,SEEK_END) >= 0)
if ((size = ftell(fp)) >= 0)
if (fseek(fp,oldpos,SEEK_SET) >= 0)
return (size_t)size;
fprintf(stderr,"Cannot determine size of file \"%s\"!\n",name);
return 0;
}
int main(int argc,char *argv[])
{
int rc = 1;
if (argc == 2) {
FILE *f;
if (f = fopen(argv[1],"rb")) {
if (vlen = filesize(f,argv[1])) {
if (vobj = malloc(vlen)) {
if (fread(vobj,1,vlen,f) == vlen)
rc = vobjdump();
else
fprintf(stderr,"Read error on \"%s\"!\n",argv[1]);
free(vobj);
}
else
fprintf(stderr,"Unable to allocate %lu bytes "
"to buffer file \"%s\"!\n",vlen,argv[1]);
}
fclose(f);
}
else
fprintf(stderr,"Cannot open \"%s\" for reading!\n",argv[1]);
}
else
fprintf(stderr,"vobjdump V0.5\nWritten by Frank Wille\n"
"Usage: %s <file name>\n",argv[0]);
return rc;
}