Remove parallel unpacking

Parallel unpacking didn't really improve the speed that much. Actually
sorting the files for optimized unpack order improved speed much more
than the parallel unpacker.

Furthermore, the fork based parallel unpacker was actually pretty messy
to begin with.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

4 files changed, 10 insertions, 77 deletions

diff --git a/unpack/fill_files.c b/unpack/fill_files.c
index c0fc26c..df6ca7e 100644
--- a/unpack/fill_files.c
+++ b/unpack/fill_files.c
@@ -38,65 +38,17 @@ static int fill_files(data_reader_t *data, file_info_t *list, int flags)
 	return 0;
 }
 
-int fill_unpacked_files(fstree_t *fs, data_reader_t *data, int flags,
-			unsigned int num_jobs)
+int fill_unpacked_files(fstree_t *fs, data_reader_t *data, int flags)
 {
-	file_info_t **sublists, *it;
-	int exitstatus, status = 0;
-	unsigned int i;
-	pid_t pid;
+	file_info_t *list, *it;
+	int status = 0;
 
-	if (num_jobs < 1)
-		num_jobs = 1;
+	list = optimize_unpack_order(fs);
 
-	sublists = alloca(sizeof(sublists[0]) * num_jobs);
-	optimize_unpack_order(fs, num_jobs, sublists);
+	status = fill_files(data, list, flags);
 
-	if (num_jobs < 2) {
-		status = fill_files(data, sublists[0], flags);
-		goto out;
-	}
-
-	for (i = 0; i < num_jobs; ++i) {
-		pid = fork();
-
-		if (pid == 0) {
-			/* Kill the child when the parent process dies */
-			prctl(PR_SET_PDEATHSIG, SIGKILL);
-
-			if (fill_files(data, sublists[i], flags))
-				exit(EXIT_FAILURE);
-			exit(EXIT_SUCCESS);
-		}
-
-		if (pid < 0) {
-			perror("fork");
-			status = -1;
-			break;
-		}
-	}
-
-	for (;;) {
-		errno = 0;
-		pid = waitpid(-1, &exitstatus, 0);
-
-		if (pid < 0) {
-			if (errno == EINTR)
-				continue;
-			if (errno == ECHILD)
-				break;
-		}
-
-		if (!WIFEXITED(exitstatus) ||
-		    WEXITSTATUS(exitstatus) != EXIT_SUCCESS) {
-			status = -1;
-		}
-	}
-out:
-	for (i = 0; i < num_jobs; ++i) {
-		for (it = sublists[i]; it != NULL; it = it->next)
-			free(it->input_file);
-	}
+	for (it = list; it != NULL; it = it->next)
+		free(it->input_file);
 
 	return status;
 }
diff --git a/unpack/options.c b/unpack/options.c
index e880656..c7689eb 100644
--- a/unpack/options.c
+++ b/unpack/options.c
@@ -22,7 +22,6 @@ static struct option long_opts[] = {
 	{ "set-xattr", no_argument, NULL, 'X' },
 #endif
 	{ "set-times", no_argument, NULL, 'T' },
-	{ "jobs", required_argument, NULL, 'j' },
 	{ "describe", no_argument, NULL, 'd' },
 	{ "chmod", no_argument, NULL, 'C' },
 	{ "chown", no_argument, NULL, 'O' },
@@ -74,7 +73,6 @@ static const char *help_string =
 #endif
 "  --set-times, -T           When unpacking files to disk, set the create\n"
 "                            and modify timestamps from the squashfs image.\n"
-"  --jobs, -j <count>        Number of parallel unpacking jobs to start.\n"
 "  --chmod, -C               Change permission flags of unpacked files to\n"
 "                            those store in the squashfs image.\n"
 "  --chown, -O               Change ownership of unpacked files to the\n"
@@ -110,7 +108,7 @@ static char *get_path(char *old, const char *arg)
 
 void process_command_line(options_t *opt, int argc, char **argv)
 {
-	int i, j;
+	int i;
 
 	opt->op = OP_NONE;
 	opt->rdtree_flags = 0;
@@ -118,7 +116,6 @@ void process_command_line(options_t *opt, int argc, char **argv)
 	opt->cmdpath = NULL;
 	opt->unpack_root = NULL;
 	opt->image_name = NULL;
-	opt->num_jobs = 1;
 
 	for (;;) {
 		i = getopt_long(argc, argv, short_opts, long_opts, NULL);
@@ -159,17 +156,6 @@ void process_command_line(options_t *opt, int argc, char **argv)
 		case 'T':
 			opt->flags |= UNPACK_SET_TIMES;
 			break;
-		case 'j':
-			for (j = 0; optarg[j] != '\0'; ++j) {
-				if (j > 6 || !isdigit(optarg[j]))
-					goto fail_num_jobs;
-			}
-
-			opt->num_jobs = atoi(optarg);
-
-			if (opt->num_jobs < 1)
-				goto fail_num_jobs;
-			break;
 		case 'c':
 			opt->op = OP_CAT;
 			opt->cmdpath = get_path(opt->cmdpath, optarg);
@@ -227,7 +213,4 @@ fail_arg:
 	fprintf(stderr, "Try `%s --help' for more information.\n", __progname);
 	free(opt->cmdpath);
 	exit(EXIT_FAILURE);
-fail_num_jobs:
-	fputs("Expected a positive integer for --jobs.\n", stderr);
-	goto fail_arg;
 }
diff --git a/unpack/rdsquashfs.c b/unpack/rdsquashfs.c
index e0cfaba..ea21318 100644
--- a/unpack/rdsquashfs.c
+++ b/unpack/rdsquashfs.c
@@ -115,7 +115,7 @@ int main(int argc, char **argv)
 		if (restore_fstree(n, opt.flags))
 			goto out;
 
-		if (fill_unpacked_files(&fs, data, opt.flags, opt.num_jobs))
+		if (fill_unpacked_files(&fs, data, opt.flags))
 			goto out;
 
 		if (update_tree_attribs(&fs, n, opt.flags))
diff --git a/unpack/rdsquashfs.h b/unpack/rdsquashfs.h
index 6805bed..b5570dd 100644
--- a/unpack/rdsquashfs.h
+++ b/unpack/rdsquashfs.h
@@ -57,7 +57,6 @@ typedef struct {
 	int op;
 	int rdtree_flags;
 	int flags;
-	unsigned int num_jobs;
 	char *cmdpath;
 	const char *unpack_root;
 	const char *image_name;
@@ -69,8 +68,7 @@ int restore_fstree(tree_node_t *root, int flags);
 
 int update_tree_attribs(fstree_t *fs, tree_node_t *root, int flags);
 
-int fill_unpacked_files(fstree_t *fs, data_reader_t *data, int flags,
-			unsigned int num_jobs);
+int fill_unpacked_files(fstree_t *fs, data_reader_t *data, int flags);
 
 int describe_tree(tree_node_t *root, const char *unpack_root);