int compute_snes_checksum(void) {
int i, x, n, m, l, o;
if (snes_rom_mode == SNES_ROM_MODE_LOROM) {
if (romsize < 0x8000) {
fprintf(stderr, "COMPUTE_SNES_CHECKSUM: SNES checksum computing for a LoROM image requires a ROM of at least 32KB.\n");
return FAILED;
}
}
else {
if (romsize < 0x10000) {
fprintf(stderr, "COMPUTE_SNES_CHECKSUM: SNES checksum computing for a HiROM image requires a ROM of at least 64KB.\n");
return FAILED;
}
}
/* n = data inside 4mbit blocks, m = data outside that */
if (romsize < 512*1024) {
n = romsize;
m = 0;
}
else {
n = (romsize/(512*1024))*512*1024;
m = romsize - n;
}
/* sum all the bytes inside the 4mbit blocks */
x = 0;
for (i = 0; i < n; i++) {
if (snes_rom_mode == SNES_ROM_MODE_LOROM) {
/* skip the checksum bytes */
if (!(i == 0x7FDC || i == 0x7FDD || i == 0x7FDE || i == 0x7FDF))
x += rom[i];
}
else {
/* skip the checksum bytes */
if (!(i == 0xFFDC || i == 0xFFDD || i == 0xFFDE || i == 0xFFDF))
x += rom[i];
}
}
/* add to that the data outside the 4mbit blocks, ringbuffer style repeating
the remaining block until the the final part reaches 4mbits */
for (o = 0, l = i; i < romsize; i++, o++)
x += rom[(o % m) + l];
/* 2*255 is for the checksum and its complement bytes that we skipped earlier */
x += 2*255;
/* compute the inverse checksum */
l = (x & 0xFFFF) ^ 0xFFFF;
/* insert the checksum bytes */
if (snes_rom_mode == SNES_ROM_MODE_LOROM) {
mem_insert(0x7FDC, l & 0xFF);
mem_insert(0x7FDD, (l >> 8) & 0xFF);
mem_insert(0x7FDE, x & 0xFF);
mem_insert(0x7FDF, (x >> 8) & 0xFF);
}
int mem_insert_allow_overwrite(int address, unsigned char data, unsigned int allowed_overwrites) {
if (rom_usage[address] > allowed_overwrites)
return mem_insert(address, data);
rom_usage[address]++;
rom[address] = data;
return SUCCEEDED;
}
int compute_gb_complement_check(void) {
int i, x;
if (romsize < 0x8000) {
fprintf(stderr, "COMPUTE_GB_COMPLEMENT_CHECK: GB complement check computing requires a ROM of at least 32KB.\n");
return FAILED;
}
i = 0;
for (x = 0x134; x <= 0x14C; x++)
i += rom[x];
i += 25;
mem_insert(0x14D, 0 - (i & 0xFF));
return SUCCEEDED;
}
/*!
* \brief Insert string into string
*
* Insert \p s into \p *str. It the function succeeds. \p *str will be passed to
* `free()` and \p *str will be updated to point to the newly allocated string.
* If the function fails, \p *str will be left unchanged.
*
* \param[in,out] str Pointer to string to modify
* \param[in] pos Position in which to insert new string
* (0 \<= \p pos \<= \p *mem_size)
* \param[in] s New string to insert
*
* \return Nothing if successful. Otherwise, the error code.
*/
oc::result<void> str_insert(char **str, size_t pos, const char *s)
{
size_t str_size;
str_size = strlen(*str);
if (pos > str_size) {
return std::make_error_code(std::errc::invalid_argument);
} else if (str_size == SIZE_MAX) {
return std::make_error_code(std::errc::value_too_large);
}
++str_size;
return mem_insert(reinterpret_cast<void **>(str), &str_size, pos,
s, strlen(s));
}
int compute_gb_checksum(void) {
int i, x;
if (romsize < 0x8000) {
fprintf(stderr, "COMPUTE_GB_CHECKSUM: GB checksum computing requires a ROM of at least 32KB.\n");
return FAILED;
}
i = 0;
for (x = 0; x < 0x14E; x++)
i += rom[x];
for (x = 0x150; x < romsize; x++)
i += rom[x];
mem_insert(0x14E, (i >> 8) & 0xFF);
mem_insert(0x14F, i & 0xFF);
return SUCCEEDED;
}
int insert_sections(void) {
struct section *s, **sa;
int d, f, i, x, t, q, sn, p;
char *ram_slots[256], *c;
/* initialize ram slots */
for (i = 0; i < 256; i++)
ram_slots[i] = NULL;
/* find all touched slots */
s = sec_first;
while (s != NULL) {
if (s->status == SECTION_STATUS_RAM && ram_slots[s->slot] == NULL) {
ram_slots[s->slot] = malloc(slots[s->slot].size);
if (ram_slots[s->slot] == NULL) {
fprintf(stderr, "INSERT_SECTIONS: Out of memory error.\n");
return FAILED;
}
memset(ram_slots[s->slot], 0, slots[s->slot].size);
}
s = s->next;
}
/* count the sections */
i = 0;
s = sec_first;
while (s != NULL) {
/* no references - skip it */
if (s->alive == YES)
i++;
s = s->next;
}
sn = i;
if (sn == 0)
return SUCCEEDED;
sa = malloc(sizeof(struct section *) * sn);
if (sa == NULL) {
fprintf(stderr, "INSERT_SECTIONS: Out of memory error.\n");
return FAILED;
}
/* insert the sections into an array for sorting */
i = 0;
s = sec_first;
while (s != NULL) {
/* no references - skip it */
if (s->alive == YES)
sa[i++] = s;
s = s->next;
}
/* sort the sections by size, biggest first */
qsort(sa, sn, sizeof(struct section *), _sections_sort);
/* print the sizes (DEBUG) */
/*
for (d = 0; d < i; d++)
fprintf(stderr, "SIZE: %d\n", sa[d]->size);
*/
/* ram sections */
p = 0;
while (p < sn) {
s = sa[p++];
/* search for free space */
if (s->status == SECTION_STATUS_RAM) {
c = ram_slots[s->slot];
i = slots[s->slot].size;
t = 0;
for (x = 0; x < i; x++, c++) {
if (*c == 0) {
for (q = 0; x < i && q < s->size; x++, q++, c++) {
if (*c != 0)
break;
}
if (q == s->size) {
t = 1;
break;
}
}
}
if (t == 0) {
fprintf(stderr, "INSERT_SECTIONS: No room for RAM section \"%s\" (%d bytes) in slot %d.\n", s->name, s->size, s->slot);
return FAILED;
}
/* mark as used */
c = c - s->size;
for (i = 0; i < s->size; i++, c++)
*c = 1;
s->address = c - s->size - ram_slots[s->slot];
}
}
/* free tmp memory */
for (i = 0; i < 256; i++) {
if (ram_slots[i] != NULL)
free(ram_slots[i]);
}
/* force sections */
p = 0;
while (p < sn) {
s = sa[p++];
if (s->status == SECTION_STATUS_FORCE) {
memory_file_id = s->file_id;
banksize = banksizes[s->bank];
pc_bank = s->address;
pc_slot = slots[s->slot].address + pc_bank;
pc_full = pc_bank + bankaddress[s->bank];
pc_slot_max = slots[s->slot].address + slots[s->slot].size;
d = pc_full;
i = d + s->size;
s->output_address = d;
section_overwrite = OFF;
if (i > romsize) {
fprintf(stderr, "%s:%s: INSERT_SECTIONS: Section \"%s\" (%d bytes) goes beyond the ROM size.\n", get_file_name(s->file_id),
get_source_file_name(s->file_id, s->file_id_source), s->name, s->size);
return FAILED;
}
if (s->address + s->size > banksize) {
fprintf(stderr, "%s:%s: INSERT_SECTIONS: Section \"%s\" (%d bytes) overflows from ROM bank %d.\n", get_file_name(s->file_id),
get_source_file_name(s->file_id, s->file_id_source), s->name, s->size, s->bank);
return FAILED;
}
for (; d < i; d++) {
if (rom_usage[d] != 0 && rom[d] != s->data[d - pc_full])
break;
}
if (d == i) {
for (i = 0; i < s->size; i++) {
if (mem_insert_pc(s->data[i], s->slot, s->bank) == FAILED)
return FAILED;
}
}
else {
fprintf(stderr, "%s:%s: INSERT_SECTIONS: No room for section \"%s\" (%d bytes).\n", get_file_name(s->file_id),
get_source_file_name(s->file_id, s->file_id_source), s->name, s->size);
return FAILED;
}
}
}
/* absolute sections */
p = 0;
while (p < sn) {
s = sa[p++];
if (s->status == SECTION_STATUS_ABSOLUTE) {
d = s->address;
s->output_address = d;
section_overwrite = ON;
for (i = 0; i < s->size; i++) {
if (mem_insert(d + i, s->data[i]) == FAILED)
return FAILED;
}
}
}
/* semisubfree sections */
p = 0;
while (p < sn) {
s = sa[p++];
if (s->status == SECTION_STATUS_SEMISUBFREE) {
pc_bank = 0;
d = bankaddress[s->bank];
/* align the starting address */
f = (pc_bank + d) % s->alignment;
if (f > 0)
pc_bank += s->alignment - f;
i = FAILED;
while (i == FAILED) {
f = pc_bank;
for (x = 0; pc_bank < s->address && rom_usage[pc_bank + d] == 0 && x < s->size; pc_bank++, x++)
;
if (x == s->size) {
i = SUCCEEDED;
break;
}
if (pc_bank == s->address) {
fprintf(stderr, "%s:%s: INSERT_SECTIONS: No room for section \"%s\" (%d bytes) in ROM bank %d.\n", get_file_name(s->file_id),
get_source_file_name(s->file_id, s->file_id_source), s->name, s->size, s->bank);
return FAILED;
}
/* find the next starting address */
f = (pc_bank + d) % s->alignment;
if (f > 0)
pc_bank += s->alignment - f;
for (; pc_bank < s->address && rom_usage[pc_bank + d] != 0; pc_bank += s->alignment)
;
}
memory_file_id = s->file_id;
banksize = banksizes[s->bank];
pc_bank = f;
pc_slot = slots[s->slot].address + pc_bank;
pc_full = pc_bank + bankaddress[s->bank];
pc_slot_max = slots[s->slot].address + slots[s->slot].size;
s->address = pc_bank;
s->output_address = pc_full;
section_overwrite = OFF;
for (i = 0; i < s->size; i++) {
if (mem_insert_pc(s->data[i], s->slot, s->bank) == FAILED)
return FAILED;
}
}
}
/* free & semifree sections */
p = 0;
while (p < sn) {
s = sa[p++];
if (s->status == SECTION_STATUS_FREE || s->status == SECTION_STATUS_SEMIFREE) {
pc_bank = s->address;
d = bankaddress[s->bank];
/* align the starting address */
f = (pc_bank + d) % s->alignment;
if (f > 0)
pc_bank += s->alignment - f;
i = FAILED;
while (i == FAILED) {
f = pc_bank;
for (x = 0; pc_bank < banksizes[s->bank] && rom_usage[pc_bank + d] == 0 && x < s->size; pc_bank++, x++)
;
if (x == s->size) {
i = SUCCEEDED;
break;
}
if (pc_bank == banksizes[s->bank]) {
fprintf(stderr, "%s:%s: INSERT_SECTIONS: No room for section \"%s\" (%d bytes) in ROM bank %d.\n", get_file_name(s->file_id),
get_source_file_name(s->file_id, s->file_id_source), s->name, s->size, s->bank);
return FAILED;
}
/* find the next starting address */
f = (pc_bank + d) % s->alignment;
if (f > 0)
pc_bank += s->alignment - f;
for (; pc_bank < banksizes[s->bank] && rom_usage[pc_bank + d] != 0; pc_bank += s->alignment)
;
}
memory_file_id = s->file_id;
banksize = banksizes[s->bank];
pc_bank = f;
pc_slot = slots[s->slot].address + pc_bank;
pc_full = pc_bank + bankaddress[s->bank];
pc_slot_max = slots[s->slot].address + slots[s->slot].size;
s->address = pc_bank;
s->output_address = pc_full;
section_overwrite = OFF;
for (i = 0; i < s->size; i++) {
if (mem_insert_pc(s->data[i], s->slot, s->bank) == FAILED)
return FAILED;
}
}
}
/* superfree sections */
p = 0;
while (p < sn) {
s = sa[p++];
if (s->status == SECTION_STATUS_SUPERFREE) {
/* go through all the banks */
i = FAILED;
f = 0;
for (q = 0; i == FAILED && q < rombanks; q++) {
pc_bank = 0;
d = bankaddress[q];
/* align the starting address */
f = (pc_bank + d) % s->alignment;
if (f > 0)
pc_bank += s->alignment - f;
/* if the slotsize and banksize differ -> try the next bank */
if (banksizes[q] != slots[s->slot].size)
continue;
while (i == FAILED) {
f = pc_bank;
for (x = 0; pc_bank < banksizes[q] && rom_usage[pc_bank + d] == 0 && x < s->size; pc_bank++, x++)
;
if (x == s->size) {
i = SUCCEEDED;
break;
}
if (pc_bank == banksizes[q])
break;
/* find the next starting address */
f = (pc_bank + d) % s->alignment;
if (f > 0)
pc_bank += s->alignment - f;
for (; pc_bank < banksizes[s->bank] && rom_usage[pc_bank + d] != 0; pc_bank += s->alignment)
;
}
}
if (i == SUCCEEDED) {
s->bank = q-1;
memory_file_id = s->file_id;
banksize = banksizes[s->bank];
pc_bank = f;
pc_slot = pc_bank;
pc_full = pc_bank + bankaddress[s->bank];
pc_slot_max = slots[s->slot].size;
s->address = pc_bank;
s->output_address = pc_full;
section_overwrite = OFF;
for (i = 0; i < s->size; i++)
if (mem_insert_pc(s->data[i], s->slot, s->bank) == FAILED)
return FAILED;
}
else {
fprintf(stderr, "%s:%s: INSERT_SECTIONS: No room for section \"%s\" (%d bytes).\n", get_file_name(s->file_id),
get_source_file_name(s->file_id, s->file_id_source), s->name, s->size);
return FAILED;
}
}
}
/* overwrite sections */
p = 0;
while (p < sn) {
s = sa[p++];
if (s->status == SECTION_STATUS_OVERWRITE) {
memory_file_id = s->file_id;
banksize = banksizes[s->bank];
pc_bank = s->address;
pc_slot = slots[s->slot].address + pc_bank;
pc_full = pc_bank + bankaddress[s->bank];
pc_slot_max = slots[s->slot].address + slots[s->slot].size;
s->output_address = pc_full;
section_overwrite = ON;
if (pc_full + s->size > romsize) {
fprintf(stderr, "%s:%s: INSERT_SECTIONS: Section \"%s\" (%d bytes) goes beyond the ROM size.\n", get_file_name(s->file_id),
get_source_file_name(s->file_id, s->file_id_source), s->name, s->size);
return FAILED;
}
if (s->address + s->size > banksize) {
fprintf(stderr, "%s:%s: INSERT_SECTIONS: Section \"%s\" (%d bytes) overflows from ROM bank %d.\n", get_file_name(s->file_id),
get_source_file_name(s->file_id, s->file_id_source), s->name, s->size, s->bank);
return FAILED;
}
for (i = 0; i < s->size; i++) {
if (mem_insert_pc(s->data[i], s->slot, s->bank) == FAILED)
return FAILED;
}
}
}
free(sa);
return SUCCEEDED;
}
