termux · Grimler91 · Jul 25, 2022 · Jul 30, 2022 · thunder-coding · Aug 2, 2022
diff --git a/Makefile.am b/Makefile.am
@@ -17,8 +17,9 @@
 # <https://www.gnu.org/licenses/>.
 
 SUBDIRS = tests
-AM_CXXFLAGS = -std=c++11 -Wall -Wextra -pedantic
+AM_CXXFLAGS = $(PTHREAD_CFLAGS) -std=c++11 -Wall -Wextra -pedantic
+LIBS = $(PTHREAD_LIBS)
 
 bin_PROGRAMS = termux-elf-cleaner
 
-termux_elf_cleaner_SOURCES = elf-cleaner.cpp arghandling.c
+termux_elf_cleaner_SOURCES = elf-cleaner.cpp arghandling.c cpucount.c
diff --git a/README.md b/README.md
@@ -56,6 +56,8 @@ Options:
 
 SPDX-License-Identifier: [GPL-3.0-or-later](https://spdx.org/licenses/GPL-3.0-or-later.html)
 
+License is GPL-3.0-or-later in all source files unless specified otherwise in file header. 
+
 ## See also
 
 * [Bionic's related docs](https://android.googlesource.com/platform/bionic/+/refs/heads/master/android-changes-for-ndk-developers.md)
diff --git a/configure.ac b/configure.ac
@@ -31,6 +31,10 @@ AC_PROG_CC
 AC_PROG_CXX
 AC_LANG(C++)
 
+AC_CONFIG_MACRO_DIR([m4])
+
+AX_PTHREAD
+
 copyright="Copyright (C) 2022 Termux."
 AC_DEFINE_UNQUOTED(COPYRIGHT, ["$copyright"],
   [Short copyright string for this version of termux-elf-cleaner.])

diff --git a/cpucount.c b/cpucount.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: CC0-1.0
+
+/* Based on cpucount.c from github.com/cathugger/mkp224o */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+
+static int parsecpuinfo(void)
+{
+	unsigned char cpubitmap[128];
+
+	memset(cpubitmap,0,sizeof(cpubitmap));
+
+	FILE *f = fopen("/proc/cpuinfo","r");
+	if (!f)
+		return -1;
+
+	char buf[8192];
+	while (fgets(buf,sizeof(buf),f)) {
+		// we don't like newlines
+		for (char *p = buf;*p;++p) {
+			if (*p == '\n') {
+				*p = 0;
+				break;
+			}
+		}
+		// split ':'
+		char *v = 0;
+		for (char *p = buf;*p;++p) {
+			if (*p == ':') {
+				*p = 0;
+				v = p + 1;
+				break;
+			}
+		}
+		// key padding
+		size_t kl = strlen(buf);
+		while (kl > 0 && (buf[kl - 1] == '\t' || buf[kl - 1] == ' ')) {
+			--kl;
+			buf[kl] = 0;
+		}
+		// space before value
+		if (v) {
+			while (*v && (*v == ' ' || *v == '\t'))
+				++v;
+		}
+		// check what we need
+		if (strcasecmp(buf,"processor") == 0 && v) {
+			char *endp = 0;
+			long n = strtol(v,&endp,10);
+			if (endp && endp > v && n >= 0 && (size_t)n < sizeof(cpubitmap) * 8)
+				cpubitmap[n / 8] |= 1 << (n % 8);
+		}
+	}
+
+	fclose(f);
+
+	// count bits in bitmap
+	int ncpu = 0;
+	for (size_t n = 0;n < sizeof(cpubitmap) * 8;++n)
+		if (cpubitmap[n / 8] & (1 << (n % 8)))
+			++ncpu;
+
+	return ncpu;
+}
+
+int cpucount(void)
+{
+	int ncpu;
+	ncpu = parsecpuinfo();
+	if (ncpu > 0)
+		return ncpu;
+	return -1;
+}
diff --git a/cpucount.h b/cpucount.h
@@ -0,0 +1,2 @@
+extern "C" int
+cpucount(void);
diff --git a/elf-cleaner.cpp b/elf-cleaner.cpp
@@ -21,16 +21,18 @@ along with termux-elf-cleaner.  If not, see
 
 #include <algorithm>
 #include <fcntl.h>
+#include <pthread.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <vector>
 
 #include "arghandling.h"
-
+#include "cpucount.h"
 // Include a local elf.h copy as not all platforms have it.
 #include "elf.h"
 
@@ -55,6 +57,11 @@ int api_level = 21;
 bool dry_run = false;
 bool quiet = false;
 
+struct thread_data {
+	int argc = 0;
+	char **argv;
+};
+
 static char const *const usage_message[] =
 { "\
 \n\
@@ -65,6 +72,7 @@ Options:\n\
 \n\
 --api-level NN        choose target api level, i.e. 21, 24, ..\n\
 --dry-run             print info but but do not remove entries\n\
+--jobs N              allow N jobs, defaults to $(ncproc)\n\
 --quiet               do not print info about removed entries\n\
 --help                display this help and exit\n\
 --version             output version information and exit\n"
@@ -299,6 +307,18 @@ int parse_file(const char *file_name)
 	return 0;
 }
 
+void *file_parse_loop(void *td)
+{
+	struct thread_data *data = (struct thread_data *) td;
+	for (int i = 0; i < data->argc; i++) {
+		char *file_name = (*data).argv[i];
+		int ret = parse_file(file_name);
+		if (ret != 0)
+			break;
+	}
+	return NULL;
+}
+
 int main(int argc, char **argv)
 {
 	int skip_args = 0;
@@ -328,15 +348,50 @@ int main(int argc, char **argv)
 		supported_dt_flags_1 = (DF_1_NOW | DF_1_GLOBAL | DF_1_NODELETE);
 	}
 
+	int num_threads = cpucount();
+	argmatch(argv, argc, "-jobs", "--jobs", 1, &num_threads, &skip_args);
+	if (num_threads <= 0)
+		num_threads = 1;
+
 	if (argmatch(argv, argc, "-dry-run", "--dry-run", 3, NULL, &skip_args))
 		dry_run = true;
 
 	if (argmatch(argv, argc, "-quiet", "--quiet", 3, NULL, &skip_args))
 		quiet = true;
 
-	for (int i = skip_args+1; i < argc; i++) {
-		if (parse_file(argv[i]) != 0)
-			return 1;
+	std::vector<pthread_t> thread(num_threads);
+	std::vector<struct thread_data> data(num_threads);
+	int num_files = argc - (skip_args+1);
+	/* Tasks per thread, rounded down */
+	int tasks_per_thread = (num_files / num_threads);
+
+	for (int i = 0; i<num_threads; i++) {
+		if (i < num_files % num_threads) {
+			/* Distribute 'extra' jobs (since we rounded
+			   down tasks_per_thread) */
+			data[i].argv = &argv[skip_args+1];
+			data[i].argc = tasks_per_thread + 1;
+			skip_args += tasks_per_thread + 1;
+		} else {
+			data[i].argv = &argv[skip_args+1];
+			data[i].argc = tasks_per_thread;
+			skip_args += tasks_per_thread;
+		}
+	}
+
+	/* Launch Threads */
+	for (int i = 0; i<num_threads; i++) {
+		if (data[i].argc == 0)
+			break;
+		pthread_create(&thread[i], NULL, &file_parse_loop, &data[i]);
 	}
+
+	/* Wait for Threads to Finish */
+	for (int i = 0; i<num_threads; i++) {
+		if (data[i].argc == 0)
+			break;
+		pthread_join(thread[i], NULL);
+	}
+
 	return 0;
 }