Use /dev/fd in closefrom() on FreeBSD < 8.0 and Mac OS X.

diff --git a/compat/closefrom.c b/compat/closefrom.c
index c2fe77735fdbd1a3dffcfb72ceaac2cedbfc8eef..cb7fa8a5d008b778294b6a2d2afe8695c0697da6 100644 (file)
--- a/compat/closefrom.c
+++ b/compat/closefrom.c
@@ -31,6 +31,7 @@
 # endif
 #endif /* STDC_HEADERS */
 #include <fcntl.h>
+#include <limits.h>
 #ifdef HAVE_PSTAT_GETPROC
 # include <sys/param.h>
 # include <sys/pstat.h>
@@ -55,15 +56,13 @@
 
 #include "missing.h"
 
-#ifndef HAVE_FCNTL_CLOSEM
-# ifndef HAVE_DIRFD
-#   define closefrom_fallback  closefrom
-# endif
+#if defined(HAVE_FCNTL_CLOSEM) && !defined(HAVE_DIRFD)
+# define closefrom     closefrom_fallback
 #endif
 
 /*
  * Close all file descriptors greater than or equal to lowfd.
- * This is the expensive (ballback) method.
+ * This is the expensive (fallback) method.
  */
 void
 closefrom_fallback(int lowfd)
@@ -85,7 +84,7 @@ closefrom_fallback(int lowfd)
 
     for (fd = lowfd; fd < maxfd; fd++) {
 #ifdef __APPLE__
-       /* Avoid potential crash with libdispatch when we close its fds. */
+       /* Avoid potential libdispatch crash when we close its fds. */
        (void) fcntl((int) fd, F_SETFD, FD_CLOEXEC);
 #else
        (void) close((int) fd);
@@ -122,17 +121,27 @@ closefrom(int lowfd)
 void
 closefrom(int lowfd)
 {
-    struct dirent *dent;
-    const char *errstr;
+    char path[PATH_MAX];
     DIR *dirp;
-    int fd;
 
-    /* Use /proc/self/fd directory if it exists. */
-    if ((dirp = opendir("/proc/self/fd")) != NULL) {
+    /* Use /proc/$$/fd (or /dev/fd on FreeBSD) if it exists. */
+# if defined(__FreeBSD__) || defined(__APPLE__)
+    snprintf(path, sizeof(path), "/dev/fd");
+# else
+    snprintf(path, sizeof(path), "/proc/%u/fd", (unsigned int)getpid());
+# endif
+    if ((dirp = opendir(path)) != NULL) {
+       struct dirent *dent;
        while ((dent = readdir(dirp)) != NULL) {
-           fd = strtonum(dent->d_name, lowfd, INT_MAX, &errstr);
+           const char *errstr;
+           int fd = strtonum(dent->d_name, lowfd, INT_MAX, &errstr);
            if (errstr == NULL && fd != dirfd(dirp)) {
+# ifdef __APPLE__
+               /* Avoid potential libdispatch crash when we close its fds. */
+               (void) fcntl(fd, F_SETFD, FD_CLOEXEC);
+# else
                (void) close(fd);
+# endif
            }
        }
        (void) closedir(dirp);