tools/power/turbostat: Abstrct function for parsing cpu string

Abstract parse_cpu_str() which can update any specified cpu_set by a
given cpu string. This can be used to handle further CPU limitations
from other sources like cgroup.

The cpu string parsing code is also enhanced to handle the strings that
have an extra '\n' before string terminator.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

tools/power/x86/turbostat/turbostat.c

@@ -3565,6 +3565,59 @@ int get_physical_node_id(struct cpu_topology *thiscpu)
 	return -1;
 }
 
+static int parse_cpu_str(char *cpu_str, cpu_set_t *cpu_set, int cpu_set_size)
+{
+	unsigned int start, end;
+	char *next = cpu_str;
+
+	while (next && *next) {
+
+		if (*next == '-')	/* no negative cpu numbers */
+			return 1;
+
+		start = strtoul(next, &next, 10);
+
+		if (start >= CPU_SUBSET_MAXCPUS)
+			return 1;
+		CPU_SET_S(start, cpu_set_size, cpu_set);
+
+		if (*next == '\0' || *next == '\n')
+			break;
+
+		if (*next == ',') {
+			next += 1;
+			continue;
+		}
+
+		if (*next == '-') {
+			next += 1;	/* start range */
+		} else if (*next == '.') {
+			next += 1;
+			if (*next == '.')
+				next += 1;	/* start range */
+			else
+				return 1;
+		}
+
+		end = strtoul(next, &next, 10);
+		if (end <= start)
+			return 1;
+
+		while (++start <= end) {
+			if (start >= CPU_SUBSET_MAXCPUS)
+				return 1;
+			CPU_SET_S(start, cpu_set_size, cpu_set);
+		}
+
+		if (*next == ',')
+			next += 1;
+		else if (*next != '\0' && *next != '\n')
+			return 1;
+	}
+
+	return 0;
+}
+
 int get_thread_siblings(struct cpu_topology *thiscpu)
 {
 	char path[80], character;
@@ -6384,9 +6437,6 @@ void probe_sysfs(void)
  */
 void parse_cpu_command(char *optarg)
 {
-	unsigned int start, end;
-	char *next;
-
 	if (!strcmp(optarg, "core")) {
 		if (cpu_subset)
 			goto error;
@@ -6409,52 +6459,8 @@ void parse_cpu_command(char *optarg)
 
 	CPU_ZERO_S(cpu_subset_size, cpu_subset);
 
-	next = optarg;
-
-	while (next && *next) {
-
-		if (*next == '-')	/* no negative cpu numbers */
-			goto error;
-
-		start = strtoul(next, &next, 10);
-
-		if (start >= CPU_SUBSET_MAXCPUS)
-			goto error;
-		CPU_SET_S(start, cpu_subset_size, cpu_subset);
-
-		if (*next == '\0')
-			break;
-
-		if (*next == ',') {
-			next += 1;
-			continue;
-		}
-
-		if (*next == '-') {
-			next += 1;	/* start range */
-		} else if (*next == '.') {
-			next += 1;
-			if (*next == '.')
-				next += 1;	/* start range */
-			else
-				goto error;
-		}
-
-		end = strtoul(next, &next, 10);
-		if (end <= start)
-			goto error;
-
-		while (++start <= end) {
-			if (start >= CPU_SUBSET_MAXCPUS)
-				goto error;
-			CPU_SET_S(start, cpu_subset_size, cpu_subset);
-		}
-
-		if (*next == ',')
-			next += 1;
-		else if (*next != '\0')
-			goto error;
-	}
+	if (parse_cpu_str(optarg, cpu_subset, cpu_subset_size))
+		goto error;
 
 	return;