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captain-amygdala.pistorm/platforms/amiga/hunk-reloc.c
Andrew Hutchings 10d5229b68 Add license information to source
MIT license was chosen
2021-04-16 09:06:27 +01:00

246 lines
8.0 KiB
C

// SPDX-License-Identifier: MIT
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <endian.h>
#include "hunk-reloc.h"
#ifdef FAKESTORM
#define lseek64 lseek
#endif
#define DEBUG(...)
//#define DEBUG printf
#define BE(val) be32toh(val)
#define BE16(val) be16toh(val)
#define READLW(a, b) fread(&a, 4, 1, b); a = be32toh(a);
#define READW(a, b) fread(&a, 2, 1, b); a = be16toh(a);
uint32_t lw = 0;
static uint32_t file_offset = 0, add_size = 0;
char *hunk_id_name(uint32_t index) {
switch (index) {
case HUNKTYPE_HEADER:
return "HUNK_HEADER";
case HUNKTYPE_CODE:
return "HUNK_CODE";
case HUNKTYPE_HUNK_RELOC32:
return "HUNK_RELOC32";
case HUNKTYPE_SYMBOL:
return "HUNK_SYMBOL";
case HUNKTYPE_BSS:
return "HUNK_BSS";
case HUNKTYPE_DATA:
return "HUNK_DATA";
case HUNKTYPE_END:
return "HUNK_END";
default:
return "UNKNOWN HUNK TYPE";
}
}
int process_hunk(uint32_t index, struct hunk_info *info, FILE *f, struct hunk_reloc *r) {
if (!f)
return -1;
uint32_t discard = 0, cur_hunk = 0, offs32 = 0;
switch (index) {
case HUNKTYPE_HEADER:
DEBUG("Processing hunk header.\n");
do {
READLW(discard, f);
if (discard) {
info->libnames[info->num_libs] = malloc(discard * 4);
fread(info->libnames[info->num_libs], discard, 4, f);
info->num_libs++;
}
} while (discard);
READLW(info->table_size, f);
DEBUG("Table size: %d\n", info->table_size);
READLW(info->first_hunk, f);
READLW(info->last_hunk, f);
info->num_hunks = (info->last_hunk - info->first_hunk) + 1;
DEBUG("First: %d Last: %d Num: %d\n", info->first_hunk, info->last_hunk, info->num_hunks);
info->hunk_sizes = malloc(info->num_hunks * 4);
info->hunk_offsets = malloc(info->num_hunks * 4);
for (uint32_t i = 0; i < info->table_size; i++) {
READLW(info->hunk_sizes[i], f);
DEBUG("Hunk %d: %d (%.8X)\n", i, info->hunk_sizes[i] * 4, info->hunk_sizes[i] * 4);
}
return 0;
break;
case HUNKTYPE_CODE:
DEBUG("Hunk %d: CODE.\n", info->current_hunk);
READLW(discard, f);
info->hunk_offsets[info->current_hunk] = ftell(f) - file_offset;
DEBUG("Code hunk size: %d (%.8X)\n", discard * 4, discard * 4);
fseek(f, discard * 4, SEEK_CUR);
return 0;
break;
case HUNKTYPE_HUNK_RELOC32:
DEBUG("Hunk %d: RELOC32.\n", info->current_hunk);
DEBUG("Processing Reloc32 hunk.\n");
do {
READLW(discard, f);
if (discard && discard != 0xFFFFFFFF) {
READLW(cur_hunk, f);
DEBUG("Relocating %d offsets pointing to hunk %d.\n", discard, cur_hunk);
for(uint32_t i = 0; i < discard; i++) {
READLW(offs32, f);
DEBUG("#%d: @%.8X in hunk %d\n", i + 1, offs32, cur_hunk);
r[info->reloc_hunks].offset = offs32;
r[info->reloc_hunks].src_hunk = info->current_hunk;
r[info->reloc_hunks].target_hunk = cur_hunk;
info->reloc_hunks++;
}
}
} while(discard);
return 0;
break;
case HUNKTYPE_SYMBOL:
DEBUG("Hunk %d: SYMBOL.\n", info->current_hunk);
DEBUG("Processing Symbol hunk.\n");
READLW(discard, f);
do {
if (discard) {
char sstr[256];
memset(sstr, 0x00, 256);
fread(sstr, discard, 4, f);
READLW(discard, f);
DEBUG("Symbol: %s - %.8X\n", sstr, discard);
}
READLW(discard, f);
} while (discard);
return 0;
break;
case HUNKTYPE_BSS:
DEBUG("Hunk %d: BSS.\n", info->current_hunk);
READLW(discard, f);
info->hunk_offsets[info->current_hunk] = ftell(f) - file_offset;
DEBUG("Skipping BSS hunk. Size: %d\n", discard * 4);
add_size += (discard * 4);
return 0;
case HUNKTYPE_DATA:
DEBUG("Hunk %d: DATA.\n", info->current_hunk);
READLW(discard, f);
info->hunk_offsets[info->current_hunk] = ftell(f) - file_offset;
DEBUG("Skipping data hunk. Size: %d.\n", discard * 4);
fseek(f, discard * 4, SEEK_CUR);
return 0;
break;
case HUNKTYPE_END:
DEBUG("END: Ending hunk %d.\n", info->current_hunk);
info->current_hunk++;
return 0;
break;
default:
DEBUG("Unknown hunk type %.8X! Can't process!\n", index);
break;
}
return -1;
}
void reloc_hunk(struct hunk_reloc *h, uint8_t *buf, struct hunk_info *i) {
uint32_t rel = i->hunk_offsets[h->target_hunk];
uint32_t *src_ptr = (uint32_t *)(&buf[i->hunk_offsets[h->src_hunk] + h->offset]);
uint32_t src = be32toh(*src_ptr);
uint32_t dst = src + i->base_offset + rel;
DEBUG("%.8X -> %.8X\n", src, dst);
*src_ptr = htobe32(dst);
}
void process_hunks(FILE *in, struct hunk_info *h_info, struct hunk_reloc *r, uint32_t offset) {
READLW(lw, in);
DEBUG("Hunk ID: %.8X (%s)\n", lw, hunk_id_name(lw));
file_offset = offset;
add_size = 0;
while (!feof(in) && process_hunk(lw, h_info, in, r) != -1) {
READLW(lw, in);
if (feof(in)) goto end_parse;
DEBUG("Hunk ID: %.8X (%s)\n", lw, hunk_id_name(lw));
DEBUG("File pos: %.8lX\n", ftell(in) - file_offset);
}
end_parse:;
DEBUG("Done processing hunks.\n");
}
void reloc_hunks(struct hunk_reloc *r, uint8_t *buf, struct hunk_info *h_info) {
DEBUG("Relocating %d offsets.\n", h_info->reloc_hunks);
for (uint32_t i = 0; i < h_info->reloc_hunks; i++) {
DEBUG("Relocating offset %d.\n", i);
reloc_hunk(&r[i], buf, h_info);
}
DEBUG("Done relocating offsets.\n");
}
struct LoadSegBlock {
uint32_t lsb_ID;
uint32_t lsb_SummedLongs;
int32_t lsb_ChkSum;
uint32_t lsb_HostID;
uint32_t lsb_Next;
uint32_t lsb_LoadData[123]; // Assumes 512 byte blocks
};
#define LOADSEG_IDENTIFIER 0x4C534547
int load_lseg(int fd, uint8_t **buf_p, struct hunk_info *i, struct hunk_reloc *relocs) {
if (fd == -1)
return -1;
uint8_t *block = malloc(512);
uint32_t next_blk = 0;
struct LoadSegBlock *lsb = (struct LoadSegBlock *)block;
read(fd, block, 512);
if (BE(lsb->lsb_ID) != LOADSEG_IDENTIFIER) {
DEBUG("[LOAD_LSEG] Attempted to load a non LSEG-block: %.8X", BE(lsb->lsb_ID));
goto fail;
}
char *filename = "data/lsegout.bin";
FILE *out = fopen(filename, "wb+");
DEBUG("[LOAD_LSEG] LSEG data:\n");
DEBUG("[LOAD_LSEG] Longs: %d HostID: %d\n", BE(lsb->lsb_SummedLongs), BE(lsb->lsb_HostID));
DEBUG("[LOAD_LSEG] Next: %d LoadData: %p\n", BE(lsb->lsb_Next), (void *)lsb->lsb_LoadData);
next_blk = BE(lsb->lsb_Next);
do {
next_blk = BE(lsb->lsb_Next);
fwrite(lsb->lsb_LoadData, 4, 123, out);
lseek64(fd, next_blk * 512, SEEK_SET);
read(fd, block, 512);
} while (next_blk != 0xFFFFFFFF);
uint32_t file_size = ftell(out);
fseek(out, 0, SEEK_SET);
uint8_t *buf = malloc(file_size + 1024);
fread(buf, file_size, 1, out);
fseek(out, 0, SEEK_SET);
process_hunks(out, i, relocs, 0x0);
fclose(out);
*buf_p = buf;
i->byte_size = file_size;
i->alloc_size = file_size + add_size;
return 0;
fail:;
if (block)
free(block);
return -1;
}