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-rw-r--r--compat/closefrom.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/compat/closefrom.c b/compat/closefrom.c
new file mode 100644
index 0000000..be00823
--- /dev/null
+++ b/compat/closefrom.c
@@ -0,0 +1,155 @@
+/*
+ * Copyright (c) 2004-2005 Todd C. Miller <Todd.Miller@courtesan.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef HAVE_CLOSEFROM
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <unistd.h>
+#include <stdio.h>
+#ifdef HAVE_FCNTL_H
+# include <fcntl.h>
+#endif
+#include <limits.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include <unistd.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
+#if defined(HAVE_LIBPROC_H)
+# include <libproc.h>
+#endif
+
+#include "compat.h"
+
+#ifndef OPEN_MAX
+# define OPEN_MAX 256
+#endif
+
+#if 0
+__unused static const char rcsid[] = "$Sudo: closefrom.c,v 1.11 2006/08/17 15:26:54 millert Exp $";
+#endif /* lint */
+
+#ifndef HAVE_FCNTL_CLOSEM
+/*
+ * Close all file descriptors greater than or equal to lowfd.
+ */
+static void
+closefrom_fallback(int lowfd)
+{
+ long fd, maxfd;
+
+ /*
+ * Fall back on sysconf() or getdtablesize(). We avoid checking
+ * resource limits since it is possible to open a file descriptor
+ * and then drop the rlimit such that it is below the open fd.
+ */
+#ifdef HAVE_SYSCONF
+ maxfd = sysconf(_SC_OPEN_MAX);
+#else
+ maxfd = getdtablesize();
+#endif /* HAVE_SYSCONF */
+ if (maxfd < 0)
+ maxfd = OPEN_MAX;
+
+ for (fd = lowfd; fd < maxfd; fd++)
+ (void) close((int) fd);
+}
+#endif /* HAVE_FCNTL_CLOSEM */
+
+#ifdef HAVE_FCNTL_CLOSEM
+void
+closefrom(int lowfd)
+{
+ (void) fcntl(lowfd, F_CLOSEM, 0);
+}
+#elif defined(HAVE_LIBPROC_H) && defined(HAVE_PROC_PIDINFO)
+void
+closefrom(int lowfd)
+{
+ int i, r, sz;
+ pid_t pid = getpid();
+ struct proc_fdinfo *fdinfo_buf = NULL;
+
+ sz = proc_pidinfo(pid, PROC_PIDLISTFDS, 0, NULL, 0);
+ if (sz == 0)
+ return; /* no fds, really? */
+ else if (sz == -1)
+ goto fallback;
+ if ((fdinfo_buf = malloc(sz)) == NULL)
+ goto fallback;
+ r = proc_pidinfo(pid, PROC_PIDLISTFDS, 0, fdinfo_buf, sz);
+ if (r < 0 || r > sz)
+ goto fallback;
+ for (i = 0; i < r / (int)PROC_PIDLISTFD_SIZE; i++) {
+ if (fdinfo_buf[i].proc_fd >= lowfd)
+ close(fdinfo_buf[i].proc_fd);
+ }
+ free(fdinfo_buf);
+ return;
+ fallback:
+ free(fdinfo_buf);
+ closefrom_fallback(lowfd);
+ return;
+}
+#elif defined(HAVE_DIRFD) && defined(HAVE_PROC_PID)
+void
+closefrom(int lowfd)
+{
+ long fd;
+ char fdpath[PATH_MAX], *endp;
+ struct dirent *dent;
+ DIR *dirp;
+ int len;
+
+ /* Check for a /proc/$$/fd directory. */
+ len = snprintf(fdpath, sizeof(fdpath), "/proc/%ld/fd", (long)getpid());
+ if (len > 0 && (size_t)len < sizeof(fdpath) && (dirp = opendir(fdpath))) {
+ while ((dent = readdir(dirp)) != NULL) {
+ fd = strtol(dent->d_name, &endp, 10);
+ if (dent->d_name != endp && *endp == '\0' &&
+ fd >= 0 && fd < INT_MAX && fd >= lowfd && fd != dirfd(dirp))
+ (void) close((int) fd);
+ }
+ (void) closedir(dirp);
+ return;
+ }
+ /* /proc/$$/fd strategy failed, fall back to brute force closure */
+ closefrom_fallback(lowfd);
+}
+#else
+void
+closefrom(int lowfd)
+{
+ closefrom_fallback(lowfd);
+}
+#endif /* !HAVE_FCNTL_CLOSEM */
+#endif /* HAVE_CLOSEFROM */