crtools: Cleanup threads stuff parsing

Move the whole code dealing with parsing threads at collect_pstree
stage into one function.

The nr_threads calculation is performed inside it based on the amount
of directories in /proc/pid/task, not the Threads: count in status.

Error from xrealloc is ignored by now.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

cr-dump.c

@@ -687,47 +687,34 @@ err:
 	return ret;
 }
 
-static int parse_threads(pid_t pid, int nr_threads, u32 **threads)
+static int parse_threads(pid_t pid, int *nr_threads, u32 **threads)
 {
 	struct dirent *de;
 	DIR *dir;
-
 	u32 *t = NULL;
-	int ret = -1, i = 0;
-
-	ret = -1;
+	int nr = 1;
 
 	dir = opendir_proc("%d/task", pid);
 	if (!dir) {
 		pr_perror("Can't open %d/task", pid);
-		goto err;
+		return -1;
 	}
 
-	t = xmalloc(nr_threads);
-	if (!t)
-		goto err;
-
 	while ((de = readdir(dir))) {
 		/* We expect numbers only here */
 		if (de->d_name[0] == '.')
 			continue;
 
-		if (i >= nr_threads) {
-			pr_err("Threads inconsistency, kernel bug?\n");
-			goto err;
-		}
-
-		t[i++] = atoi(de->d_name);
+		t = xrealloc(t, nr * sizeof(u32));
+		t[nr - 1] = atoi(de->d_name);
+		nr++;
 	}
 
 	closedir(dir);
 
-	*threads = t, t = NULL;
-	ret = 0;
-
-err:
-	xfree(t);
-	return ret;
+	*threads = t;
+	*nr_threads = nr - 1;
+	return 0;
 }
 
 static struct pstree_item *find_pstree_entry(pid_t pid)
@@ -737,7 +724,7 @@ static struct pstree_item *find_pstree_entry(pid_t pid)
 	u32 *threads = NULL;
 	u32 nr_allocated = 0;
 	u32 nr_children = 0;
-	u32 nr_threads = 0;
+	int nr_threads = 0;
 	char *children_str = NULL;
 	FILE *file;
 	char *tok;
@@ -756,33 +743,8 @@ static struct pstree_item *find_pstree_entry(pid_t pid)
 	}
 
 	children_str = xstrdup(loc_buf);
-	if (!children_str)
-		goto err;
-
 	fclose(file), file = NULL;
 
-	file = fopen_proc("%d/status", "r", pid);
-	if (!file) {
-		pr_perror("Can't open %d status", pid);
-		goto err;
-	}
-
-	while ((fgets(loc_buf, sizeof(loc_buf), file))) {
-		if (!strncmp(loc_buf, "Threads:", 8)) {
-			nr_threads = atoi(&loc_buf[9]);
-			if (children_str)
-				break;
-		} else
-			continue;
-	}
-
-	fclose(file), file = NULL;
-
-	if (nr_threads < 1) {
-		pr_err("Unable to find out how many threads are used\n");
-		goto err;
-	}
-
 	if (!children_str) {
 		pr_err("Children marker is not found\n");
 		goto err;
@@ -792,7 +754,7 @@ static struct pstree_item *find_pstree_entry(pid_t pid)
 	if (!item)
 		goto err;
 
-	if (parse_threads(pid, nr_threads, &threads))
+	if (parse_threads(pid, &nr_threads, &threads))
 		goto err_free;
 
 	tok = strtok(children_str, " \n");