Utility function and macro to copy Lisp string to C string.

* lisp.h (xlispstrdupa): New macro.
(xlispstrdup): New prototype.
* alloc.c (xlispstrdup): New function.
* callint.c (Fcall_interactively):
* fileio.c (Ffile_name_directory, Fexpand_file_name)
(Fsubstitute_in_file_name):
* frame.c (Fmake_terminal_frame): Use xlispstrdupa.
* image.c (x_create_bitmap_from_file):
* w32term.c (w32_term_init):
* xterm.c (x_term_init): Use xlispstrdup.

9 files changed, 42 insertions, 32 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 8a3186b85f2..415c4c3f525 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,17 @@
+2013-08-14  Dmitry Antipov  <dmantipov@yandex.ru>
+
+        Utility function and macro to copy Lisp string to C string.
+        * lisp.h (xlispstrdupa): New macro.
+        (xlispstrdup): New prototype.
+        * alloc.c (xlispstrdup): New function.
+        * callint.c (Fcall_interactively):
+        * fileio.c (Ffile_name_directory, Fexpand_file_name)
+        (Fsubstitute_in_file_name):
+        * frame.c (Fmake_terminal_frame): Use xlispstrdupa.
+        * image.c (x_create_bitmap_from_file):
+        * w32term.c (w32_term_init):
+        * xterm.c (x_term_init): Use xlispstrdup.
+
 2013-08-14  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
         * image.c (imagemagick_load_image): Make animated pictures work.
diff --git a/src/alloc.c b/src/alloc.c
index 2c2232601cb..c0d8c32b440 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -802,6 +802,15 @@ xstrdup (const char *s)
   return memcpy (xmalloc (size), s, size);
 }
 
+/* Like above, but duplicates Lisp string to C string.  */
+
+char *
+xlispstrdup (Lisp_Object string)
+{
+  ptrdiff_t size = SBYTES (string) + 1;
+  return memcpy (xmalloc (size), SSDATA (string), size);
+}
+
 /* Like putenv, but (1) use the equivalent of xmalloc and (2) the
    argument is a const pointer.  */
 
diff --git a/src/callint.c b/src/callint.c
index f43a5a990db..25096af5068 100644
--- a/src/callint.c
+++ b/src/callint.c
@@ -331,12 +331,9 @@ invoke it.  If KEYS is omitted or nil, the return value of
 
   /* If SPECS is set to a string, use it as an interactive prompt.  */
   if (STRINGP (specs))
-    {
-      /* Make a copy of string so that if a GC relocates specs,
-         `string' will still be valid.  */
-      string = alloca (SBYTES (specs) + 1);
-      memcpy (string, SSDATA (specs), SBYTES (specs) + 1);
-    }
+    /* Make a copy of string so that if a GC relocates specs,
+       `string' will still be valid.  */
+    string = xlispstrdupa (specs);
   else
     {
       Lisp_Object input;
diff --git a/src/fileio.c b/src/fileio.c
index 6ec5f78c2cf..08caf102266 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -366,8 +366,7 @@ Given a Unix syntax file name, returns a string ending in slash.  */)
     }
 
 #ifdef DOS_NT
-  beg = alloca (SBYTES (filename) + 1);
-  memcpy (beg, SSDATA (filename), SBYTES (filename) + 1);
+  beg = xlispstrdupa (filename);
 #else
   beg = SSDATA (filename);
 #endif
@@ -944,8 +943,7 @@ filesystem tree, not (expand-file-name ".."  dirname).  */)
 #endif
 
   /* Make a local copy of nm[] to protect it from GC in DECODE_FILE below.  */
-  nm = alloca (SBYTES (name) + 1);
-  memcpy (nm, SSDATA (name), SBYTES (name) + 1);
+  nm = xlispstrdupa (name);
 
 #ifdef DOS_NT
   /* Note if special escape prefix is present, but remove for now.  */
@@ -1693,8 +1691,7 @@ those `/' is discarded.  */)
   /* Always work on a copy of the string, in case GC happens during
      decode of environment variables, causing the original Lisp_String
      data to be relocated.  */
-  nm = alloca (SBYTES (filename) + 1);
-  memcpy (nm, SDATA (filename), SBYTES (filename) + 1);
+  nm = xlispstrdupa (filename);
 
 #ifdef DOS_NT
   dostounix_filename (nm, multibyte);
diff --git a/src/frame.c b/src/frame.c
index a1f151a221e..bb44f3cc987 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -692,22 +692,14 @@ affects all frames on the same terminal device.  */)
                        ? FRAME_TTY (XFRAME (selected_frame))->name
                        : NULL));
       if (!NILP (tty))
-        {
-          name = alloca (SBYTES (tty) + 1);
-          memcpy (name, SSDATA (tty), SBYTES (tty));
-          name[SBYTES (tty)] = 0;
-        }
+        name = xlispstrdupa (tty);
 
       tty_type = get_future_frame_param
         (Qtty_type, parms, (FRAME_TERMCAP_P (XFRAME (selected_frame))
                             ? FRAME_TTY (XFRAME (selected_frame))->type
                             : NULL));
       if (!NILP (tty_type))
-        {
-          type = alloca (SBYTES (tty_type) + 1);
-          memcpy (type, SSDATA (tty_type), SBYTES (tty_type));
-          type[SBYTES (tty_type)] = 0;
-        }
+        type = xlispstrdupa (tty_type);
 
       t = init_tty (name, type, 0); /* Errors are not fatal.  */
     }
diff --git a/src/image.c b/src/image.c
index b2d6726c1a4..f71ba211d44 100644
--- a/src/image.c
+++ b/src/image.c
@@ -302,11 +302,10 @@ x_create_bitmap_from_file (struct frame *f, Lisp_Object file)
   id = x_allocate_bitmap_record (f);
   dpyinfo->bitmaps[id - 1].img = bitmap;
   dpyinfo->bitmaps[id - 1].refcount = 1;
-  dpyinfo->bitmaps[id - 1].file = xmalloc (SBYTES (file) + 1);
+  dpyinfo->bitmaps[id - 1].file = xlispstrdup (file);
   dpyinfo->bitmaps[id - 1].depth = 1;
   dpyinfo->bitmaps[id - 1].height = ns_image_width (bitmap);
   dpyinfo->bitmaps[id - 1].width = ns_image_height (bitmap);
-  strcpy (dpyinfo->bitmaps[id - 1].file, SSDATA (file));
   return id;
 #endif
 
@@ -345,11 +344,10 @@ x_create_bitmap_from_file (struct frame *f, Lisp_Object file)
   dpyinfo->bitmaps[id - 1].pixmap = bitmap;
   dpyinfo->bitmaps[id - 1].have_mask = 0;
   dpyinfo->bitmaps[id - 1].refcount = 1;
-  dpyinfo->bitmaps[id - 1].file = xmalloc (SBYTES (file) + 1);
+  dpyinfo->bitmaps[id - 1].file = xlispstrdup (file);
   dpyinfo->bitmaps[id - 1].depth = 1;
   dpyinfo->bitmaps[id - 1].height = height;
   dpyinfo->bitmaps[id - 1].width = width;
-  strcpy (dpyinfo->bitmaps[id - 1].file, SSDATA (file));
 
   return id;
 #endif /* HAVE_X_WINDOWS */
diff --git a/src/lisp.h b/src/lisp.h
index 8dca073a83a..6d79bb1d6a5 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -4255,10 +4255,17 @@ extern void *xnrealloc (void *, ptrdiff_t, ptrdiff_t);
 extern void *xpalloc (void *, ptrdiff_t *, ptrdiff_t, ptrdiff_t, ptrdiff_t);
 
 extern char *xstrdup (const char *);
+extern char *xlispstrdup (Lisp_Object);
 extern void xputenv (const char *);
 
 extern char *egetenv (const char *);
 
+/* Copy Lisp string to temporary (allocated on stack) C string.  */
+
+#define xlispstrdupa(string)                    \
+  memcpy (alloca (SBYTES (string) + 1),         \
+          SSDATA (string), SBYTES (string) + 1)
+
 /* Set up the name of the machine we're running on.  */
 extern void init_system_name (void);
 
diff --git a/src/w32term.c b/src/w32term.c
index 03a9af12ea8..7d51850559b 100644
--- a/src/w32term.c
+++ b/src/w32term.c
@@ -6463,9 +6463,7 @@ w32_term_init (Lisp_Object display_name, char *xrm_option, char *resource_name)
   terminal = w32_create_terminal (dpyinfo);
 
   /* Set the name of the terminal. */
-  terminal->name = xmalloc (SBYTES (display_name) + 1);
-  strncpy (terminal->name, SDATA (display_name), SBYTES (display_name));
-  terminal->name[SBYTES (display_name)] = 0;
+  terminal->name = xlispstrdup (display_name);
 
   dpyinfo->xrdb = xrm_option ? w32_make_rdb (xrm_option) : NULL;
 
diff --git a/src/xterm.c b/src/xterm.c
index 15ad3bdf851..9e1e32a2faf 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -10038,9 +10038,7 @@ x_term_init (Lisp_Object display_name, char *xrm_option, char *resource_name)
   dpyinfo->display = dpy;
 
   /* Set the name of the terminal. */
-  terminal->name = xmalloc (SBYTES (display_name) + 1);
-  memcpy (terminal->name, SSDATA (display_name), SBYTES (display_name));
-  terminal->name[SBYTES (display_name)] = 0;
+  terminal->name = xlispstrdup (display_name);
 
 #if 0
   XSetAfterFunction (x_current_display, x_trace_wire);