xz: Remember the filter chains and the largest Block in parse_block_list()

This commit is contained in:
Lasse Collin 2024-05-12 15:48:45 +03:00
parent 46ab56968f
commit 81d350dab8
3 changed files with 33 additions and 0 deletions

View File

@ -92,6 +92,12 @@ parse_block_list(const char *str_const)
free(opt_block_list);
opt_block_list = xmalloc((count + 1) * sizeof(block_list_entry));
// Clear the bitmask of filter chains in use.
block_list_chain_mask = 0;
// Reset the largest Block size found in --block-list.
block_list_largest = 0;
for (size_t i = 0; i < count; ++i) {
// Locate the next comma and replace it with \0.
char *p = strchr(str, ',');
@ -128,7 +134,11 @@ parse_block_list(const char *str_const)
const uint32_t filter_num = (uint32_t)(str[0] - '0');
opt_block_list[i].filters_index = filter_num;
block_list_chain_mask |= 1U << filter_num;
str += 2;
} else {
// This Block uses the default filter chain.
block_list_chain_mask |= 1U << 0;
}
if (str[0] == '\0') {
@ -152,6 +162,14 @@ parse_block_list(const char *str_const)
opt_block_list[i].size = UINT64_MAX;
}
// Remember the largest Block size in the list.
//
// NOTE: Do this after handling the special value 0
// because when 0 is used, we don't want to reduce
// the Block size of the multithreaded encoder.
if (block_list_largest < opt_block_list[i].size)
block_list_largest = opt_block_list[i].size;
}
// Be standards compliant: p + 1 is undefined behavior

View File

@ -27,6 +27,8 @@ bool opt_auto_adjust = true;
bool opt_single_stream = false;
uint64_t opt_block_size = 0;
block_list_entry *opt_block_list = NULL;
uint64_t block_list_largest;
uint32_t block_list_chain_mask;
/// Stream used to communicate with liblzma
static lzma_stream strm = LZMA_STREAM_INIT;

View File

@ -65,6 +65,19 @@ extern uint64_t opt_block_size;
/// List of block size and filter chain pointer pairs.
extern block_list_entry *opt_block_list;
/// Size of the largest Block that was specified in --block-list.
/// This is used to limit the block_size option of multithreaded encoder.
/// It's waste of memory to specify a too large block_size and reducing
/// it might even allow using more threads in some cases.
///
/// NOTE: If the last entry in --block-list is the special value of 0
/// (which gets converted to UINT64_MAX), it counts here as UINT64_MAX too.
/// This way the multithreaded encoder's Block size won't be reduced.
extern uint64_t block_list_largest;
/// Bitmask indicating which filter chains we specified in --block-list.
extern uint32_t block_list_chain_mask;
/// Set the integrity check type used when compressing
extern void coder_set_check(lzma_check check);