Update closefrom() function

Import from sudo. Adapt the build system to detect the required features.

1 files changed, 69 insertions, 36 deletions

diff --git a/src/closefrom.c b/src/closefrom.c
index b7e2ad5..423a004 100644
--- a/src/closefrom.c
+++ b/src/closefrom.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2004-2005, 2007, 2010
+ * Copyright (c) 2004-2005, 2007, 2010, 2012-2014
  *	Todd C. Miller <Todd.Miller@courtesan.com>
  *
  * Permission to use, copy, modify, and distribute this software for any
@@ -18,7 +18,6 @@
 #include <config.h>
 
 #include <sys/types.h>
-#include <sys/param.h>
 #include <unistd.h>
 #include <stdio.h>
 #ifdef STDC_HEADERS
@@ -30,20 +29,26 @@
 # endif
 #endif /* STDC_HEADERS */
 #include <fcntl.h>
-#ifdef HAVE_DIRENT_H
-# include <dirent.h>
-# define NAMLEN(dirent) strlen((dirent)->d_name)
+#include <limits.h>
+#ifdef HAVE_PSTAT_GETPROC
+# include <sys/param.h>
+# include <sys/pstat.h>
 #else
-# define dirent direct
-# define NAMLEN(dirent) (dirent)->d_namlen
-# ifdef HAVE_SYS_NDIR_H
-#  include <sys/ndir.h>
-# endif
-# ifdef HAVE_SYS_DIR_H
-#  include <sys/dir.h>
-# endif
-# ifdef HAVE_NDIR_H
-#  include <ndir.h>
+# ifdef HAVE_DIRENT_H
+#  include <dirent.h>
+#  define NAMLEN(dirent) strlen((dirent)->d_name)
+# else
+#  define dirent direct
+#  define NAMLEN(dirent) (dirent)->d_namlen
+#  ifdef HAVE_SYS_NDIR_H
+#   include <sys/ndir.h>
+#  endif
+#  ifdef HAVE_SYS_DIR_H
+#   include <sys/dir.h>
+#  endif
+#  ifdef HAVE_NDIR_H
+#   include <ndir.h>
+#  endif
 # endif
 #endif
 
@@ -51,15 +56,13 @@
 # define OPEN_MAX 256
 #endif
 
-#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)
@@ -79,44 +82,74 @@ closefrom_fallback(int lowfd)
 	if (maxfd < 0)
 		maxfd = OPEN_MAX;
 
-	for (fd = lowfd; fd < maxfd; fd++)
+	for (fd = lowfd; fd < maxfd; fd++) {
+#ifdef __APPLE__
+		/* Avoid potential libdispatch crash when we close its fds. */
+		(void)fcntl((int)fd, F_SETFD, FD_CLOEXEC);
+#else
 		(void)close((int)fd);
+#endif
+	}
 }
 
 /*
  * Close all file descriptors greater than or equal to lowfd.
  * We try the fast way first, falling back on the slow method.
  */
-#ifdef HAVE_FCNTL_CLOSEM
+#if defined(HAVE_FCNTL_CLOSEM)
 void
 closefrom(int lowfd)
 {
 	if (fcntl(lowfd, F_CLOSEM, 0) == -1)
 		closefrom_fallback(lowfd);
 }
-#else
-# ifdef HAVE_DIRFD
+#elif defined(HAVE_PSTAT_GETPROC)
+void
+closefrom(int lowfd)
+{
+	struct pst_status pstat;
+	int fd;
+
+	if (pstat_getproc(&pstat, sizeof(pstat), 0, getpid()) != -1) {
+		for (fd = lowfd; fd <= pstat.pst_highestfd; fd++)
+			(void)close(fd);
+	} else {
+		closefrom_fallback(lowfd);
+	}
+}
+#elif defined(HAVE_DIRFD)
 void
 closefrom(int lowfd)
 {
-	struct dirent *dent;
+	const char *path;
 	DIR *dirp;
-	char *endp;
-	long fd;
 
-	/* Use /proc/self/fd directory if it exists. */
-	dirp = opendir("/proc/self/fd");
-	if (dirp != NULL) {
+	/* Use /proc/self/fd (or /dev/fd on FreeBSD) if it exists. */
+# if defined(__FreeBSD__) || defined(__APPLE__)
+	path = "/dev/fd";
+# else
+	path = "/proc/self/fd";
+# endif
+	if ((dirp = opendir(path)) != NULL) {
+		struct dirent *dent;
+
 		while ((dent = readdir(dirp)) != NULL) {
-			fd = strtol(dent->d_name, &endp, 10);
-			if (dent->d_name != endp && *endp == '\0' &&
-			    fd >= 0 && fd < INT_MAX && fd >= lowfd &&
-			    fd != dirfd(dirp))
-				(void)close((int)fd);
+			const char *errstr;
+			int fd;
+
+			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);
 	} else
 		closefrom_fallback(lowfd);
 }
-#endif /* HAVE_DIRFD */
 #endif /* HAVE_FCNTL_CLOSEM */