mx_util: Add close_range syscall wrapper for glibc < 2.34

mariux64 · May 9, 2022 · 16aee83 · 16aee83
1 parent 79ce67c
commit 16aee83
Show file tree

Hide file tree

Showing 2 changed files with 25 additions and 0 deletions.
diff --git a/mx_util.h b/mx_util.h
@@ -183,4 +183,9 @@ time_t mx_clock_boottime(void);
 int mx_call_external(char *helper, char **argv);
 char *mx_pipe_external(char *args, char **argv);
 
+#if __GLIBC__ <2 || __GLIBC__ == 2 && __GLIBC_MINOR__ < 34
+#include <sys/syscall.h>
+#define close_range(first, last, flags) syscall(SYS_close_range, first, last, flags)
+#endif
+
 #endif
diff --git a/test_mx_util.c b/test_mx_util.c
@@ -5,6 +5,8 @@
 #include <string.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 
 #include "mx_util.h"
 #include "mx_proc.h"
@@ -589,6 +591,23 @@ static void test_mx_call_external(void) {
     assert(errno == EPROTO);
 }
 
+static void test_mx_closerange(void) {
+    int res;
+
+    int fd1 = open("/dev/null", O_RDONLY);
+    assert (fd1 != -1);
+    int fd2 = dup2(fd1, 100);
+    assert (fd2 == 100 );
+
+    res=close_range(3, ~0u, 0);
+    assert(res == 0);
+
+    res = close(fd1);
+    assert (res == -1 && errno == EBADF);
+    res = close(fd2);
+    assert (res == -1 && errno == EBADF);
+}
+
 int main(void)
 {
     test_mx_strskipwhitespaces();
@@ -611,5 +630,6 @@ int main(void)
     test_mx_df();
     test_mx_pipe_external();
     test_mx_call_external();
+    test_mx_closerange();
     return 0;
 }