libarchive: add capability to unpack to mem.buffer
The performance and number of processes for a "depmod -a" with gzipped
modules was abysmal. This patch adds a code path without fork,
benefiting all users of xmalloc_open_zipped_read_close.
"modinfo radeon.ko.gz", a single-file reader, got 30% faster.
"depmod -a", which used to fork over 800 times, got 20% faster.
Heavily based on a patch by Lauri Kasanen <curaga@operamail.com>
function old new delta
setup_transformer_on_fd - 159 +159
transformer_write - 122 +122
fork_transformer - 112 +112
xmalloc_open_zipped_read_close 63 118 +55
read_bunzip 1866 1896 +30
xtransformer_write - 19 +19
unzip_main 2449 2462 +13
bbunpack 755 766 +11
unpack_lzma_stream 2717 2723 +6
unpack_xz_stream 2393 2397 +4
unpack_Z_stream 1173 1175 +2
inflate_unzip 111 105 -6
check_signature16 70 63 -7
unpack_bz2_stream 359 349 -10
unpack_unxz 12 - -12
unpack_unlzma 12 - -12
unpack_uncompress 12 - -12
unpack_gunzip 12 - -12
unpack_bunzip2 12 - -12
open_transformer 106 92 -14
inflate_unzip_internal 1945 1916 -29
unpack_gz_stream 693 655 -38
open_zipped 89 47 -42
setup_unzip_on_fd 142 53 -89
------------------------------------------------------------------------------
(add/remove: 4/5 grow/shrink: 7/8 up/down: 533/-295) Total: 238 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/archival/libarchive/decompress_unlzma.c b/archival/libarchive/decompress_unlzma.c
index ccedac4..c8622f9 100644
--- a/archival/libarchive/decompress_unlzma.c
+++ b/archival/libarchive/decompress_unlzma.c
@@ -206,7 +206,7 @@
IF_DESKTOP(long long) int FAST_FUNC
-unpack_lzma_stream(transformer_state_t *xstate UNUSED_PARAM, int src_fd, int dst_fd)
+unpack_lzma_stream(transformer_state_t *xstate)
{
IF_DESKTOP(long long total_written = 0;)
lzma_header_t header;
@@ -223,7 +223,7 @@
int state = 0;
uint32_t rep0 = 1, rep1 = 1, rep2 = 1, rep3 = 1;
- if (full_read(src_fd, &header, sizeof(header)) != sizeof(header)
+ if (full_read(xstate->src_fd, &header, sizeof(header)) != sizeof(header)
|| header.pos >= (9 * 5 * 5)
) {
bb_error_msg("bad lzma header");
@@ -258,7 +258,7 @@
p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
}
- rc = rc_init(src_fd); /*, RC_BUFFER_SIZE); */
+ rc = rc_init(xstate->src_fd); /*, RC_BUFFER_SIZE); */
while (global_pos + buffer_pos < header.dst_size) {
int pos_state = (buffer_pos + global_pos) & pos_state_mask;
@@ -306,7 +306,7 @@
if (buffer_pos == header.dict_size) {
buffer_pos = 0;
global_pos += header.dict_size;
- if (full_write(dst_fd, buffer, header.dict_size) != (ssize_t)header.dict_size)
+ if (transformer_write(xstate, buffer, header.dict_size) != (ssize_t)header.dict_size)
goto bad;
IF_DESKTOP(total_written += header.dict_size;)
}
@@ -440,7 +440,7 @@
if (buffer_pos == header.dict_size) {
buffer_pos = 0;
global_pos += header.dict_size;
- if (full_write(dst_fd, buffer, header.dict_size) != (ssize_t)header.dict_size)
+ if (transformer_write(xstate, buffer, header.dict_size) != (ssize_t)header.dict_size)
goto bad;
IF_DESKTOP(total_written += header.dict_size;)
}
@@ -455,7 +455,7 @@
{
IF_NOT_DESKTOP(int total_written = 0; /* success */)
IF_DESKTOP(total_written += buffer_pos;)
- if (full_write(dst_fd, buffer, buffer_pos) != (ssize_t)buffer_pos) {
+ if (transformer_write(xstate, buffer, buffer_pos) != (ssize_t)buffer_pos) {
bad:
total_written = -1; /* failure */
}