diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/comp/lz4.c | 35 |
1 files changed, 31 insertions, 4 deletions
diff --git a/lib/comp/lz4.c b/lib/comp/lz4.c index 63ed528..e0bba9c 100644 --- a/lib/comp/lz4.c +++ b/lib/comp/lz4.c @@ -11,6 +11,7 @@ typedef struct { compressor_t base; + bool high_compression; } lz4_compressor_t; typedef struct { @@ -19,14 +20,15 @@ typedef struct { } lz4_options; #define LZ4LEGACY 1 +#define LZ4_FLAG_HC 0x01 static int lz4_write_options(compressor_t *base, int fd) { + lz4_compressor_t *lz4 = (lz4_compressor_t *)base; lz4_options opt = { .version = htole32(LZ4LEGACY), - .flags = htole32(0), + .flags = htole32(lz4->high_compression ? LZ4_FLAG_HC : 0), }; - (void)base; return generic_write_options(fd, &opt, sizeof(opt)); } @@ -53,10 +55,16 @@ static int lz4_read_options(compressor_t *base, int fd) static ssize_t lz4_comp_block(compressor_t *base, const uint8_t *in, size_t size, uint8_t *out, size_t outsize) { + lz4_compressor_t *lz4 = (lz4_compressor_t *)base; int ret; - (void)base; - ret = LZ4_compress_default((void *)in, (void *)out, size, outsize); + if (lz4->high_compression) { + ret = LZ4_compress_HC((void *)in, (void *)out, + size, outsize, LZ4HC_CLEVEL_MAX); + } else { + ret = LZ4_compress_default((void *)in, (void *)out, + size, outsize); + } if (ret < 0) { fputs("internal error in lz4 compressor\n", stderr); @@ -99,6 +107,19 @@ compressor_t *create_lz4_compressor(bool compress, size_t block_size, return NULL; } + lz4->high_compression = false; + + if (options != NULL) { + if (strcmp(options, "hc") == 0) { + lz4->high_compression = true; + } else { + fputs("Unsupported extra options for lz4 " + "compressor.\n", stderr); + free(lz4); + return NULL; + } + } + base->destroy = lz4_destroy; base->do_block = compress ? lz4_comp_block : lz4_uncomp_block; base->write_options = lz4_write_options; @@ -108,4 +129,10 @@ compressor_t *create_lz4_compressor(bool compress, size_t block_size, void compressor_lz4_print_help(void) { + fputs("Available options for lz4 compressor:\n" + "\n" + " hc If present, use slower but better compressing\n" + " variant of lz4.\n" + "\n", + stdout); } |