Fix the check for cpu being in cpuset range

Also add a testcase to make sure that the new function is correct.
In order to share the cpuset range checking code with with the
test, move it into cpuset.c.  Not sure whether we want that in a
utils.c instead.

Signed-off-by: Serge Hallyn <[email protected]>

.gitignore

@@ -25,3 +25,6 @@ stamp-h1
 lxcfs.1
 share/00-lxcfs.conf
 share/lxc.mount.hook
+tests/cpusetrange
+tests/test-read
+cpuset.o

Makefile.am

@@ -13,7 +13,7 @@ AM_LDFLAGS = $(DBUS_LIBS) $(NIH_LIBS) $(NIH_DBUS_LIBS) $(CGMANAGER_LIBS) $(FUSE_
 
 bin_PROGRAMS = lxcfs
 
-lxcfs_SOURCES = lxcfs.c cgmanager.c cgmanager.h
+lxcfs_SOURCES = lxcfs.c cgmanager.c cgmanager.h cpuset.c
 
 EXTRA_DIST = \
 	lxcfs.man.add
@@ -28,7 +28,10 @@ endif
 TEST_READ: tests/test-read.c
 	$(CC) -o tests/test-read tests/test-read.c
 
-tests: TEST_READ
+TEST_CPUSET: tests/cpusetrange.c cpuset.c
+	$(CC) -o tests/cpusetrange tests/cpusetrange.c cpuset.c
+
+tests: TEST_READ TEST_CPUSET
 
 distclean:
 	rm -rf .deps/ \

cpuset.c

@@ -0,0 +1,45 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
+/*
+ * Helper functions for cpuset_in-set
+ */
+static char *cpuset_nexttok(const char *c)
+{
+	char *r = strchr(c+1, ',');
+	if (r)
+		return r+1;
+	return NULL;
+}
+
+static int cpuset_getrange(const char *c, int *a, int *b)
+{
+	int ret;
+
+	ret = sscanf(c, "%d-%d", a, b);
+	return ret;
+}
+
+/*
+ * cpusets are in format "1,2-3,4"
+ * iow, comma-delimited ranges
+ */
+bool cpu_in_cpuset(int cpu, const char *cpuset)
+{
+	const char *c;
+
+	for (c = cpuset; c; c = cpuset_nexttok(c)) {
+		int a, b, ret;
+
+		ret = cpuset_getrange(c, &a, &b);
+		if (ret == 1 && cpu == a) // "1" or "1,6"
+			return true;
+		else if (ret == 2 && cpu >= a && cpu <= b) // range match
+			return true;
+	}
+
+	return false;
+}
+

lxcfs.c

@@ -1684,47 +1684,7 @@ static char *get_cpuset(const char *cg)
 	return answer;
 }
 
-/*
- * Helper functions for cpuset_in-set
- */
-char *cpuset_nexttok(const char *c)
-{
-	char *r = strchr(c+1, ',');
-	if (r)
-		return r+1;
-	return NULL;
-}
-
-int cpuset_getrange(const char *c, int *a, int *b)
-{
-	int ret;
-
-	ret = sscanf(c, "%d-%d", a, b);
-	return ret;
-}
-
-/*
- * cpusets are in format "1,2-3,4"
- * iow, comma-delimited ranges
- */
-static bool cpu_in_cpuset(int cpu, const char *cpuset)
-{
-	const char *c;
-
-	for (c = cpuset; c; c = cpuset_nexttok(c)) {
-		int a, b, ret;
-
-		ret = cpuset_getrange(c, &a, &b);
-		if (ret == 1 && cpu == a)
-			return true;
-		if (ret != 2) // bad cpuset!
-			return false;
-		if (cpu >= a && cpu <= b)
-			return true;
-	}
-
-	return false;
-}
+bool cpu_in_cpuset(int cpu, const char *cpuset);
 
 static bool cpuline_in_cpuset(const char *line, const char *cpuset)
 {

tests/cpusetrange.c

@@ -0,0 +1,50 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
+/*
+ * cpusets are in format "1,2-3,4"
+ * iow, comma-delimited ranges
+ */
+extern bool cpu_in_cpuset(int cpu, const char *cpuset);
+
+void verify(bool condition) {
+	if (condition) {
+		printf(" PASS\n");
+	} else {
+		printf(" FAIL!\n");
+		exit(1);
+	}
+}
+
+int main() {
+	char *a = "1,2";
+	char *b = "1-3,5";
+	char *c = "1,4-5";
+	char *d = "";
+	char *e = "\n";
+
+	printf("1 in %s", a);
+	verify(cpu_in_cpuset(1, a));
+	printf("2 in %s", a);
+	verify(cpu_in_cpuset(2, a));
+	printf("NOT 4 in %s", a);
+	verify(!cpu_in_cpuset(4, a));
+	printf("1 in %s", b);
+	verify(cpu_in_cpuset(1, b));
+	printf("NOT 4 in %s", b);
+	verify(!cpu_in_cpuset(4, b));
+	printf("5 in %s", b);
+	verify(cpu_in_cpuset(5, b));
+	printf("1 in %s", c);
+	verify(cpu_in_cpuset(1, c));
+	printf("5 in %s", c);
+	verify(cpu_in_cpuset(5, c));
+	printf("NOT 6 in %s", c);
+	verify(!cpu_in_cpuset(6, c));
+	printf("NOT 6 in empty set");
+	verify(!cpu_in_cpuset(6, d));
+	printf("NOT 6 in empty set(2)");
+	verify(!cpu_in_cpuset(6, e));
+}