Fix quitting bug when buffers are frozen

Problem noted by Eli Zaretskii in:
http://lists.gnu.org/archive/html/emacs-devel/2017-01/msg00721.html
This patch also fixes some other issues in that report.
* src/lisp.h (incr_rarely_quit): Remove.
All callers changed to use rarely_quit directly.
* src/search.c (freeze_buffer_relocation)
(thaw_buffer_relocation): New functions.
(looking_at_1, fast_looking_at, search_buffer):
Use them to fix bug when quitting when buffers are frozen.
* src/sysdep.c (emacs_intr_read): Rename from emacs_nointr_read.
All uses changed.

1 files changed, 27 insertions, 30 deletions

diff --git a/src/search.c b/src/search.c
index 084adda097b..33cb02aa7af 100644
--- a/src/search.c
+++ b/src/search.c
@@ -99,6 +99,25 @@ matcher_overflow (void)
   error ("Stack overflow in regexp matcher");
 }
 
+static void
+freeze_buffer_relocation (void)
+{
+#ifdef REL_ALLOC
+  /* Prevent ralloc.c from relocating the current buffer while
+     searching it.  */
+  r_alloc_inhibit_buffer_relocation (1);
+  record_unwind_protect_int (r_alloc_inhibit_buffer_relocation, 0);
+#endif
+}
+
+static void
+thaw_buffer_relocation (void)
+{
+#ifdef REL_ALLOC
+  unbind_to (SPECPDL_INDEX () - 1, Qnil);
+#endif
+}
+
 /* Compile a regexp and signal a Lisp error if anything goes wrong.
    PATTERN is the pattern to compile.
    CP is the place to put the result.
@@ -300,19 +319,13 @@ looking_at_1 (Lisp_Object string, bool posix)
 
   re_match_object = Qnil;
 
-#ifdef REL_ALLOC
-  /* Prevent ralloc.c from relocating the current buffer while
-     searching it.  */
-  r_alloc_inhibit_buffer_relocation (1);
-#endif
+  freeze_buffer_relocation ();
   i = re_match_2 (bufp, (char *) p1, s1, (char *) p2, s2,
                   PT_BYTE - BEGV_BYTE,
                   (NILP (Vinhibit_changing_match_data)
                    ? &search_regs : NULL),
                   ZV_BYTE - BEGV_BYTE);
-#ifdef REL_ALLOC
-  r_alloc_inhibit_buffer_relocation (0);
-#endif
+  thaw_buffer_relocation ();
 
   if (i == -2)
     matcher_overflow ();
@@ -553,16 +566,10 @@ fast_looking_at (Lisp_Object regexp, ptrdiff_t pos, ptrdiff_t pos_byte,
     }
 
   buf = compile_pattern (regexp, 0, Qnil, 0, multibyte);
-#ifdef REL_ALLOC
-  /* Prevent ralloc.c from relocating the current buffer while
-     searching it.  */
-  r_alloc_inhibit_buffer_relocation (1);
-#endif
+  freeze_buffer_relocation ();
   len = re_match_2 (buf, (char *) p1, s1, (char *) p2, s2,
                     pos_byte, NULL, limit_byte);
-#ifdef REL_ALLOC
-  r_alloc_inhibit_buffer_relocation (0);
-#endif
+  thaw_buffer_relocation ();
 
   return len;
 }
@@ -1204,11 +1211,7 @@ search_buffer (Lisp_Object string, ptrdiff_t pos, ptrdiff_t pos_byte,
         }
       re_match_object = Qnil;
 
-#ifdef REL_ALLOC
-  /* Prevent ralloc.c from relocating the current buffer while
-     searching it.  */
-  r_alloc_inhibit_buffer_relocation (1);
-#endif
+      freeze_buffer_relocation ();
 
       while (n < 0)
         {
@@ -1250,9 +1253,7 @@ search_buffer (Lisp_Object string, ptrdiff_t pos, ptrdiff_t pos_byte,
             }
           else
             {
-#ifdef REL_ALLOC
-              r_alloc_inhibit_buffer_relocation (0);
-#endif
+              thaw_buffer_relocation ();
               return (n);
             }
           n++;
@@ -1295,17 +1296,13 @@ search_buffer (Lisp_Object string, ptrdiff_t pos, ptrdiff_t pos_byte,
             }
           else
             {
-#ifdef REL_ALLOC
-              r_alloc_inhibit_buffer_relocation (0);
-#endif
+              thaw_buffer_relocation ();
               return (0 - n);
             }
           n--;
           maybe_quit ();
         }
-#ifdef REL_ALLOC
-      r_alloc_inhibit_buffer_relocation (0);
-#endif
+      thaw_buffer_relocation ();
       return (pos);
     }
   else                          /* non-RE case */