Skip to content

Fix Galois field operations and add reference counting for table init… #6

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
benoit-a merged 1 commit into from
Dec 18, 2025
Merged

Fix Galois field operations and add reference counting for table init… #6

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions src/builtin/rs_vand/liberasurecode_rs_vand.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -370,7 +370,7 @@ void region_multiply(char *from_buf, char *to_buf, int mult, int xor, int blocks

if (trailing_bytes == 1) {
i = blocksize - 1;
to_buf[i] = to_buf[i] ^ (char)rs_galois_mult(from_buf[i], mult);
to_buf[i] = to_buf[i] ^ (char)rs_galois_mult((unsigned char)from_buf[i], mult);
}
} else {
for (i = 0; i < adj_blocksize; i++) {
Expand All @@ -379,7 +379,7 @@ void region_multiply(char *from_buf, char *to_buf, int mult, int xor, int blocks

if (trailing_bytes == 1) {
i = blocksize - 1;
to_buf[i] = (char)rs_galois_mult(from_buf[i], mult);
to_buf[i] = (char)rs_galois_mult((unsigned char)from_buf[i], mult);
}
}
}
Expand Down
34 changes: 24 additions & 10 deletions src/builtin/rs_vand/rs_galois.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -44,31 +44,45 @@
int *log_table = NULL;
int *ilog_table = NULL;
int *ilog_table_begin = NULL;
static int init_counter = 0;

void rs_galois_init_tables()
{
log_table = (int*)malloc(sizeof(int)*FIELD_SIZE);
ilog_table_begin = (int*)malloc(sizeof(int)*FIELD_SIZE*3);
void rs_galois_init_tables() {
if (init_counter++ > 0) {
/* already initialized */
return;
}
log_table = (int *)malloc(sizeof(int) * FIELD_SIZE);
ilog_table_begin = (int *)malloc(sizeof(int) * FIELD_SIZE * 3);
int i = 0;
int x = 1;

for (i = 0; i < GROUP_SIZE; i++) {
log_table[x] = i;
ilog_table_begin[i] = x;
ilog_table_begin[i + GROUP_SIZE] = x;
ilog_table_begin[i + (GROUP_SIZE*2)] = x;
ilog_table_begin[i + (GROUP_SIZE * 2)] = x;
x = x << 1;
if (x & FIELD_SIZE) {
x ^= PRIM_POLY;
x ^= PRIM_POLY;
}
}
ilog_table = &ilog_table_begin[GROUP_SIZE];
}

void rs_galois_deinit_tables()
{
free(log_table);
free(ilog_table_begin);
void rs_galois_deinit_tables() {
init_counter--;
if (init_counter < 0) {
/* deinit when not initialized?? */
init_counter = 0;
} else if (init_counter > 0) {
/* still at least one desc using it */
return;
} else {
free(log_table);
log_table = NULL;
free(ilog_table_begin);
ilog_table_begin = NULL;
}
}

int rs_galois_mult(int x, int y)
Expand Down