ext2fs: don't ignore return value in ext2fs_count_blocks

[tools/e2fsprogs.git] / lib / ss / pager.c

diff --git a/lib/ss/pager.c b/lib/ss/pager.c
index 1a70773..b9b8899 100644 (file)
--- a/lib/ss/pager.c
+++ b/lib/ss/pager.c
@@ -4,9 +4,17 @@
  *
  * Copyright 1987, 1988 by MIT Student Information Processing Board
  *
- * For copyright information, see copyright.h.
+ * Permission to use, copy, modify, and distribute this software and
+ * its documentation for any purpose is hereby granted, provided that
+ * the names of M.I.T. and the M.I.T. S.I.P.B. not be used in
+ * advertising or publicity pertaining to distribution of the software
+ * without specific, written prior permission.  M.I.T. and the
+ * M.I.T. S.I.P.B. make no representations about the suitability of
+ * this software for any purpose.  It is provided "as is" without
+ * express or implied warranty.
  */
 
+#include "config.h"
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
@@ -17,15 +25,44 @@ extern int errno;
 #endif
 
 #include "ss_internal.h"
-#include "copyright.h"
 #include <stdio.h>
 #include <sys/types.h>
 #include <sys/file.h>
 #include <signal.h>
+#ifdef HAVE_SYS_PRCTL_H
+#include <sys/prctl.h>
+#else
+#define PR_GET_DUMPABLE 3
+#endif
+#if (!defined(HAVE_PRCTL) && defined(linux))
+#include <sys/syscall.h>
+#endif
 
 static char MORE[] = "more";
-extern char *_ss_pager_name;
-extern char *getenv();
+extern char *getenv PROTOTYPE((const char *));
+
+char *ss_safe_getenv(const char *arg)
+{
+       if ((getuid() != geteuid()) || (getgid() != getegid()))
+               return NULL;
+#if HAVE_PRCTL
+       if (prctl(PR_GET_DUMPABLE, 0, 0, 0, 0) == 0)
+               return NULL;
+#else
+#if (defined(linux) && defined(SYS_prctl))
+       if (syscall(SYS_prctl, PR_GET_DUMPABLE, 0, 0, 0, 0) == 0)
+               return NULL;
+#endif
+#endif
+
+#if defined(HAVE_SECURE_GETENV)
+       return secure_getenv(arg);
+#elif defined(HAVE___SECURE_GETENV)
+       return __secure_getenv(arg);
+#else
+       return getenv(arg);
+#endif
+}
 
 /*
  * this needs a *lot* of work....
@@ -36,10 +73,10 @@ extern char *getenv();
  */
 
 #ifndef NO_FORK
-int ss_pager_create() 
+int ss_pager_create(void)
 {
        int filedes[2];
-     
+
        if (pipe(filedes) != 0)
                return(-1);
 
@@ -71,27 +108,38 @@ int ss_pager_create()
 }
 #endif
 
-void ss_page_stdin()
+static int write_all(int fd, char *buf, size_t count)
+{
+       ssize_t ret;
+       int c = 0;
+
+       while (count > 0) {
+               ret = write(fd, buf, count);
+               if (ret < 0) {
+                       if ((errno == EAGAIN) || (errno == EINTR))
+                               continue;
+                       return -1;
+               }
+               count -= ret;
+               buf += ret;
+               c += ret;
+       }
+       return c;
+}
+
+void ss_page_stdin(void)
 {
        int i;
+       sigset_t mask;
+
        for (i = 3; i < 32; i++)
                (void) close(i);
        (void) signal(SIGINT, SIG_DFL);
-       {
-#ifdef POSIX_SIGNALS
-               sigset_t mask;
-               
-               sigprocmask(SIG_BLOCK, 0, &mask);
-               sigdelset(&mask, SIGINT);
-               sigprocmask(SIG_SETMASK, &mask, 0);
-#else
-               int mask = sigblock(0);
-               mask &= ~sigmask(SIGINT);
-               sigsetmask(mask);
-#endif
-       }
+       sigprocmask(SIG_BLOCK, 0, &mask);
+       sigdelset(&mask, SIGINT);
+       sigprocmask(SIG_SETMASK, &mask, 0);
        if (_ss_pager_name == (char *)NULL) {
-               if ((_ss_pager_name = getenv("PAGER")) == (char *)NULL)
+               if ((_ss_pager_name = ss_safe_getenv("PAGER")) == (char *)NULL)
                        _ss_pager_name = MORE;
        }
        (void) execlp(_ss_pager_name, _ss_pager_name, (char *) NULL);
@@ -100,7 +148,7 @@ void ss_page_stdin()
                char buf[80];
                register int n;
                while ((n = read(0, buf, 80)) > 0)
-                       write(1, buf, n);
+                       write_all(1, buf, n);
        }
        exit(errno);
 }