This patch addresses the issues with reproducible builds when using
multithreaded xz. Previously, specifying --threads=1 instead of
--threads=[n>1] creates different output. Now, setting any number of
threads forces multithreading mode, even if there is only 1 worker
thread.
---
src/xz/Makefile.am | 1 +
src/xz/args.c | 4 +++-
src/xz/coder.c | 16 +++++++++++++---
src/xz/coder.h | 3 +++
4 files changed, 20 insertions(+), 4 deletions(-)
diff --git a/src/xz/Makefile.am b/src/xz/Makefile.am
index 4bc64f3..07ae9eb 100644
--- a/src/xz/Makefile.am
+++ b/src/xz/Makefile.am
@@ -51,6 +51,7 @@ xz_CPPFLAGS = \
-DLOCALEDIR=\"$(localedir)\" \
-I$(top_srcdir)/src/common \
-I$(top_srcdir)/src/liblzma/api \
+ -I$(top_srcdir)/src/liblzma/common \
-I$(top_builddir)/lib
xz_LDADD = $(top_builddir)/src/liblzma/liblzma.la $(CAPSICUM_LIB)
diff --git a/src/xz/args.c b/src/xz/args.c
index 9238fb3..c09c6b6 100644
--- a/src/xz/args.c
+++ b/src/xz/args.c
@@ -13,6 +13,7 @@
///////////////////////////////////////////////////////////////////////////////
#include "private.h"
+#include "common.h"
#include "getopt.h"
#include <ctype.h>
@@ -249,7 +250,8 @@ parse_real(args_info *args, int argc, char **argv)
case 'T':
// The max is from src/liblzma/common/common.h.
hardware_threads_set(str_to_uint64("threads",
- optarg, 0, 16384));
+ optarg, 0, LZMA_THREADS_MAX));
+ set_multithreaded_mode(true);
break;
// --version
diff --git a/src/xz/coder.c b/src/xz/coder.c
index 85f9543..8dfdeb2 100644
--- a/src/xz/coder.c
+++ b/src/xz/coder.c
@@ -51,6 +51,9 @@ static lzma_check check;
/// This becomes false if the --check=CHECK option is used.
static bool check_default = true;
+/// Flag to indicate multithreaded compression
+static bool multithreaded_mode = false;
+
#if defined(HAVE_ENCODERS) && defined(MYTHREAD_ENABLED)
static lzma_mt mt_options = {
.flags = 0,
@@ -211,10 +214,11 @@ coder_set_compression_settings(void)
}
}
- if (hardware_threads_get() > 1) {
+ if (multithreaded_mode) {
message(V_WARNING, _("Switching to single-threaded "
"mode due to --flush-timeout"));
hardware_threads_set(1);
+ set_multithreaded_mode(false);
}
}
@@ -225,7 +229,7 @@ coder_set_compression_settings(void)
if (opt_mode == MODE_COMPRESS) {
#ifdef HAVE_ENCODERS
# ifdef MYTHREAD_ENABLED
- if (opt_format == FORMAT_XZ && hardware_threads_get() > 1) {
+ if (opt_format == FORMAT_XZ && (hardware_threads_get() > 1 ||
multithreaded_mode)) {
mt_options.threads = hardware_threads_get();
mt_options.block_size = opt_block_size;
mt_options.check = check;
@@ -446,7 +450,7 @@ coder_init(file_pair *pair)
case FORMAT_XZ:
# ifdef MYTHREAD_ENABLED
- if (hardware_threads_get() > 1)
+ if (multithreaded_mode)
ret = lzma_stream_encoder_mt(
&strm, &mt_options);
else
@@ -933,6 +937,12 @@ coder_run(const char *filename)
return;
}
+extern void
+set_multithreaded_mode(bool mode)
+{
+ multithreaded_mode = mode;
+}
+
#ifndef NDEBUG
extern void
diff --git a/src/xz/coder.h b/src/xz/coder.h
index 583da8f..178f036 100644
--- a/src/xz/coder.h
+++ b/src/xz/coder.h
@@ -70,6 +70,9 @@ extern void coder_set_compression_settings(void);
/// Compress or decompress the given file
extern void coder_run(const char *filename);
+//// Set multithread mode true/false
+extern void set_multithreaded_mode(bool mode);
+
#ifndef NDEBUG
/// Free the memory allocated for the coder and kill the worker threads.
extern void coder_free(void);
--
2.25.1
