Initialize GnuTLS before calling gnutls_rnd

* src/gnutls.c (emacs_gnutls_global_init): Now extern.
Don’t set gnutls_global_initialized if gnutls_global_init fails.
* src/sysdep.c: Include "gnutls.h", and <gnutls/crypto.h>
if 2.12 or later, which has gnutls_rnd.
(emacs_gnutls_global_init, gnutls_rnd): New fallback
placeholder macros if before 2.12.
(init_random): Initialize gnutls globals before trying to
use gnutls_rnd.

3 files changed, 40 insertions, 25 deletions

diff --git a/src/gnutls.c b/src/gnutls.c
index a1d058fcd48..01a5983d3b0 100644
--- a/src/gnutls.c
+++ b/src/gnutls.c
@@ -1112,15 +1112,17 @@ The return value is a property list with top-level keys :warnings and
 /* Initialize global GnuTLS state to defaults.
    Call `gnutls-global-deinit' when GnuTLS usage is no longer needed.
    Return zero on success.  */
-static Lisp_Object
+Lisp_Object
 emacs_gnutls_global_init (void)
 {
   int ret = GNUTLS_E_SUCCESS;
 
   if (!gnutls_global_initialized)
-    ret = gnutls_global_init ();
-
-  gnutls_global_initialized = 1;
+    {
+      ret = gnutls_global_init ();
+      if (ret == GNUTLS_E_SUCCESS)
+        gnutls_global_initialized = 1;
+    }
 
   return gnutls_make_error (ret);
 }
diff --git a/src/gnutls.h b/src/gnutls.h
index c4fe738bfa0..8e879c168bd 100644
--- a/src/gnutls.h
+++ b/src/gnutls.h
@@ -83,6 +83,7 @@ extern ptrdiff_t emacs_gnutls_record_check_pending (gnutls_session_t state);
 extern void emacs_gnutls_transport_set_errno (gnutls_session_t state, int err);
 #endif
 extern Lisp_Object emacs_gnutls_deinit (Lisp_Object);
+extern Lisp_Object emacs_gnutls_global_init (void);
 
 #endif
 
diff --git a/src/sysdep.c b/src/sysdep.c
index 7f64a3b9fbc..6b2b2053a24 100644
--- a/src/sysdep.c
+++ b/src/sysdep.c
@@ -99,6 +99,14 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "process.h"
 #include "cm.h"
 
+#include "gnutls.h"
+#if 0x020c00 <= GNUTLS_VERSION_NUMBER
+# include <gnutls/crypto.h>
+#else
+# define emacs_gnutls_global_init() Qnil
+# define gnutls_rnd(level, data, len) (-1)
+#endif
+
 #ifdef WINDOWSNT
 #include <direct.h>
 /* In process.h which conflicts with the local copy.  */
@@ -2096,22 +2104,26 @@ void
 init_random (void)
 {
   random_seed v;
-  bool success = false;
-#ifndef WINDOWSNT
-  int fd = emacs_open ("/dev/urandom", O_RDONLY | O_BINARY, 0);
-  if (fd >= 0)
+  if (! (EQ (emacs_gnutls_global_init (), Qt)
+         && gnutls_rnd (GNUTLS_RND_NONCE, &v, sizeof v) == 0))
     {
-      success = emacs_read (fd, &v, sizeof v) == sizeof v;
-      emacs_close (fd);
-    }
+      bool success = false;
+#ifndef WINDOWSNT
+      int fd = emacs_open ("/dev/urandom", O_RDONLY | O_BINARY, 0);
+      if (0 <= fd)
+        {
+          success = emacs_read (fd, &v, sizeof v) == sizeof v;
+          emacs_close (fd);
+        }
 #else
-  success = w32_init_random (&v, sizeof v) == 0;
+      success = w32_init_random (&v, sizeof v) == 0;
 #endif
-  if (! success)
-    {
-      /* Fall back to current time value + PID.  */
-      struct timespec t = current_timespec ();
-      v = getpid () ^ t.tv_sec ^ t.tv_nsec;
+      if (! success)
+        {
+          /* Fall back to current time value + PID.  */
+          struct timespec t = current_timespec ();
+          v = getpid () ^ t.tv_sec ^ t.tv_nsec;
+        }
     }
   set_random_seed (v);
 }
@@ -2163,7 +2175,7 @@ snprintf (char *buf, size_t bufsize, char const *format, ...)
         xfree (b);
     }
 
-  if (nbytes > INT_MAX)
+  if (INT_MAX < nbytes)
     {
 #ifdef EOVERFLOW
       errno = EOVERFLOW;
@@ -2221,7 +2233,7 @@ emacs_backtrace (int backtrace_limit)
     {
       emacs_write (STDERR_FILENO, "\nBacktrace:\n", 12);
       backtrace_symbols_fd (buffer, npointers, STDERR_FILENO);
-      if (npointers > bounded_limit)
+      if (bounded_limit < npointers)
         emacs_write (STDERR_FILENO, "...\n", 4);
     }
 }
@@ -2250,7 +2262,7 @@ emacs_open (const char *file, int oflags, int mode)
   oflags |= O_CLOEXEC;
   while ((fd = open (file, oflags, mode)) < 0 && errno == EINTR)
     QUIT;
-  if (! O_CLOEXEC && fd >= 0)
+  if (! O_CLOEXEC && 0 <= fd)
     fcntl (fd, F_SETFD, FD_CLOEXEC);
   return fd;
 }
@@ -2817,9 +2829,9 @@ time_from_jiffies (unsigned long long tval, long hz)
   unsigned long long frac = tval % hz;
   int ns;
 
-  if (s > TYPE_MAXIMUM (time_t))
+  if (TYPE_MAXIMUM (time_t) < s)
     time_overflow ();
-  if (ULLONG_MAX / TIMESPEC_RESOLUTION >= LONG_MAX - 1
+  if (LONG_MAX - 1 <= ULLONG_MAX / TIMESPEC_RESOLUTION
       || frac <= ULLONG_MAX / TIMESPEC_RESOLUTION)
     ns = frac * TIMESPEC_RESOLUTION / hz;
   else
@@ -3037,7 +3049,7 @@ system_process_attributes (Lisp_Object pid)
       record_unwind_protect_int (close_file_unwind, fd);
       nread = emacs_read (fd, procbuf, sizeof procbuf - 1);
     }
-  if (nread > 0)
+  if (0 < nread)
     {
       procbuf[nread] = '\0';
       p = procbuf;
@@ -3164,12 +3176,12 @@ system_process_attributes (Lisp_Object pid)
       if (nread)
         {
           /* We don't want trailing null characters.  */
-          for (p = cmdline + nread; p > cmdline && !p[-1]; p--)
+          for (p = cmdline + nread; cmdline < p && !p[-1]; p--)
             continue;
 
           /* Escape-quote whitespace and backslashes.  */
           q = cmdline + cmdline_size;
-          while (p > cmdline)
+          while (cmdline < p)
             {
               char c = *--p;
               *--q = c ? c : ' ';