Clean up "completer_handle_brkchars" callback handling

This patch cleans up "completer_handle_brkchars" callback handling:

- Renames the function typedef to better match its intent:
  completer_ftype_void ->  completer_handle_brkchars_ftype

- Factors out common code in complete_line_internal handling the
  "handle_brkchars" callback to a separate function.

- Centralizes all the "completer method" to "handle_brkchars method"
  mapping in a single function.

gdb/ChangeLog:
2017-07-17  Pedro Alves  <palves@redhat.com>

	* cli/cli-decode.c (set_cmd_completer_handle_brkchars): Adjust to
	renames.
	* cli/cli-decode.h (struct cmd_list_element) <completer>: Move
	comments to completer_ftype's declaration.
	<completer_handle_brkchars>: Change type to
	completer_handle_brkchars_ftype.
	* command.h (completer_ftype): Add describing comment and give
	names to parameters.
	(completer_ftype_void): Rename to ...
	(completer_handle_brkchars_ftype) ... this.  Add describing comment.
	(set_cmd_completer_handle_brkchars): Adjust.
	* completer.c (filename_completer_handle_brkchars): New function.
	(complete_line_internal_normal_command): New function, factored
	out from ...
	(complete_line_internal): ... here.
	(command_completer_handle_brkchars)
	(default_completer_handle_brkchars)
	(completer_handle_brkchars_func_for_completer): New functions.
	* completer.h (set_gdb_completion_word_break_characters): Delete
	declaration.
	(completer_handle_brkchars_func_for_completer): New declaration.
	* python/py-cmd.c (cmdpy_completer_handle_brkchars): Adjust to use
	completer_handle_brkchars_func_for_completer.

7 files changed, 153 insertions, 68 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 3e41709..1439101 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,31 @@
 2017-07-17  Pedro Alves  <palves@redhat.com>
 
+	* cli/cli-decode.c (set_cmd_completer_handle_brkchars): Adjust to
+	renames.
+	* cli/cli-decode.h (struct cmd_list_element) <completer>: Move
+	comments to completer_ftype's declaration.
+	<completer_handle_brkchars>: Change type to
+	completer_handle_brkchars_ftype.
+	* command.h (completer_ftype): Add describing comment and give
+	names to parameters.
+	(completer_ftype_void): Rename to ...
+	(completer_handle_brkchars_ftype) ... this.  Add describing comment.
+	(set_cmd_completer_handle_brkchars): Adjust.
+	* completer.c (filename_completer_handle_brkchars): New function.
+	(complete_line_internal_normal_command): New function, factored
+	out from ...
+	(complete_line_internal): ... here.
+	(command_completer_handle_brkchars)
+	(default_completer_handle_brkchars)
+	(completer_handle_brkchars_func_for_completer): New functions.
+	* completer.h (set_gdb_completion_word_break_characters): Delete
+	declaration.
+	(completer_handle_brkchars_func_for_completer): New declaration.
+	* python/py-cmd.c (cmdpy_completer_handle_brkchars): Adjust to use
+	completer_handle_brkchars_func_for_completer.
+
+2017-07-17  Pedro Alves  <palves@redhat.com>
+
 	* completer.c (symbol_completer): New function, based on
 	make_symbol_completion_list_fn.
 	* completer.h (symbol_completer): New declaration.
diff --git a/gdb/cli/cli-decode.c b/gdb/cli/cli-decode.c
index 0a78f4e..064b481 100644
--- a/gdb/cli/cli-decode.c
+++ b/gdb/cli/cli-decode.c
@@ -166,9 +166,9 @@ set_cmd_completer (struct cmd_list_element *cmd, completer_ftype *completer)
 
 void
 set_cmd_completer_handle_brkchars (struct cmd_list_element *cmd,
-			       completer_ftype_void *completer_handle_brkchars)
+				   completer_handle_brkchars_ftype *func)
 {
-  cmd->completer_handle_brkchars = completer_handle_brkchars;
+  cmd->completer_handle_brkchars = func;
 }
 
 /* Add element named NAME.
diff --git a/gdb/cli/cli-decode.h b/gdb/cli/cli-decode.h
index 11248ba..50b858c 100644
--- a/gdb/cli/cli-decode.h
+++ b/gdb/cli/cli-decode.h
@@ -160,19 +160,7 @@ struct cmd_list_element
     /* The prefix command of this command.  */
     struct cmd_list_element *prefix;
 
-    /* Completion routine for this command.  TEXT is the text beyond
-       what was matched for the command itself (leading whitespace is
-       skipped).  It stops where we are supposed to stop completing
-       (rl_point) and is '\0' terminated.
-
-       Return value is a malloc'd vector of pointers to possible
-       completions terminated with NULL.  If there are no completions,
-       returning a pointer to a NULL would work but returning NULL
-       itself is also valid.  WORD points in the same buffer as TEXT,
-       and completions should be returned relative to this position.
-       For example, suppose TEXT is "foo" and we want to complete to
-       "foobar".  If WORD is "oo", return "oobar"; if WORD is
-       "baz/foo", return "baz/foobar".  */
+    /* Completion routine for this command.  */
     completer_ftype *completer;
 
     /* Handle the word break characters for this completer.  Usually
@@ -181,8 +169,7 @@ struct cmd_list_element
        a class) the word break chars may need to be redefined
        depending on the completer type (e.g., for filename
        completers).  */
-
-    completer_ftype_void *completer_handle_brkchars;
+    completer_handle_brkchars_ftype *completer_handle_brkchars;
 
     /* Destruction routine for this command.  If non-NULL, this is
        called when this command instance is destroyed.  This may be
diff --git a/gdb/command.h b/gdb/command.h
index 4a56a51..2a190d4 100644
--- a/gdb/command.h
+++ b/gdb/command.h
@@ -174,18 +174,28 @@ typedef void cmd_sfunc_ftype (char *args, int from_tty,
 extern void set_cmd_sfunc (struct cmd_list_element *cmd,
 			   cmd_sfunc_ftype *sfunc);
 
+/* A completion routine.  Return a list of possible completions.
+
+   TEXT is the text beyond what was matched for the command itself
+   (leading whitespace is skipped).  It stops where we are supposed to
+   stop completing (rl_point) and is '\0' terminated.  WORD points in
+   the same buffer as TEXT, and completions should be returned
+   relative to this position.  For example, suppose TEXT is "foo" and
+   we want to complete to "foobar".  If WORD is "oo", return "oobar";
+   if WORD is "baz/foo", return "baz/foobar".  */
 typedef VEC (char_ptr) *completer_ftype (struct cmd_list_element *,
-					 const char *, const char *);
+					 const char *text, const char *word);
 
-typedef void completer_ftype_void (struct cmd_list_element *,
-				   const char *, const char *);
+/* Same, but for set_cmd_completer_handle_brkchars.  */
+typedef void completer_handle_brkchars_ftype (struct cmd_list_element *,
+					      const char *text, const char *word);
 
 extern void set_cmd_completer (struct cmd_list_element *, completer_ftype *);
 
 /* Set the completer_handle_brkchars callback.  */
 
 extern void set_cmd_completer_handle_brkchars (struct cmd_list_element *,
-					       completer_ftype_void *);
+					       completer_handle_brkchars_ftype *);
 
 /* HACK: cagney/2002-02-23: Code, mostly in tracepoints.c, grubs
    around in cmd objects to test the value of the commands sfunc().  */
diff --git a/gdb/completer.c b/gdb/completer.c
index 89cecbc..625ff4f 100644
--- a/gdb/completer.c
+++ b/gdb/completer.c
@@ -132,6 +132,7 @@ noop_completer (struct cmd_list_element *ignore,
 }
 
 /* Complete on filenames.  */
+
 VEC (char_ptr) *
 filename_completer (struct cmd_list_element *ignore, 
 		    const char *text, const char *word)
@@ -192,6 +193,17 @@ filename_completer (struct cmd_list_element *ignore,
   return return_val;
 }
 
+/* The corresponding completer_handle_brkchars
+   implementation.  */
+
+static void
+filename_completer_handle_brkchars (struct cmd_list_element *ignore,
+				    const char *text, const char *word)
+{
+  set_rl_completer_word_break_characters
+    (gdb_completer_file_name_break_characters);
+}
+
 /* Complete on linespecs, which might be of two possible forms:
 
        file:line
@@ -703,6 +715,51 @@ typedef enum
 }
 complete_line_internal_reason;
 
+/* Helper for complete_line_internal to simplify it.  */
+
+static VEC (char_ptr) *
+complete_line_internal_normal_command (const char *command, const char *word,
+				       const char *cmd_args,
+				       complete_line_internal_reason reason,
+				       struct cmd_list_element *c)
+{
+  const char *p = cmd_args;
+
+  if (c->completer == filename_completer)
+    {
+      /* Many commands which want to complete on file names accept
+	 several file names, as in "run foo bar >>baz".  So we don't
+	 want to complete the entire text after the command, just the
+	 last word.  To this end, we need to find the beginning of the
+	 file name by starting at `word' and going backwards.  */
+      for (p = word;
+	   p > command
+	     && strchr (gdb_completer_file_name_break_characters,
+			p[-1]) == NULL;
+	   p--)
+	;
+    }
+
+  if (reason == handle_brkchars)
+    {
+      completer_handle_brkchars_ftype *brkchars_fn;
+
+      if (c->completer_handle_brkchars != NULL)
+	brkchars_fn = c->completer_handle_brkchars;
+      else
+	{
+	  brkchars_fn
+	    = (completer_handle_brkchars_func_for_completer
+	       (c->completer));
+	}
+
+      brkchars_fn (c, p, word);
+    }
+
+  if (reason != handle_brkchars && c->completer != NULL)
+    return (*c->completer) (c, p, word);
+  return NULL;
+}
 
 /* Internal function used to handle completions.
 
@@ -872,29 +929,9 @@ complete_line_internal (const char *text,
 		{
 		  /* It is a normal command; what comes after it is
 		     completed by the command's completer function.  */
-		  if (c->completer == filename_completer)
-		    {
-		      /* Many commands which want to complete on
-			 file names accept several file names, as
-			 in "run foo bar >>baz".  So we don't want
-			 to complete the entire text after the
-			 command, just the last word.  To this
-			 end, we need to find the beginning of the
-			 file name by starting at `word' and going
-			 backwards.  */
-		      for (p = word;
-			   p > tmp_command
-			     && strchr (gdb_completer_file_name_break_characters, p[-1]) == NULL;
-			   p--)
-			;
-		      set_rl_completer_word_break_characters
-			(gdb_completer_file_name_break_characters);
-		    }
-		  if (reason == handle_brkchars
-		      && c->completer_handle_brkchars != NULL)
-		    (*c->completer_handle_brkchars) (c, p, word);
-		  if (reason != handle_brkchars && c->completer != NULL)
-		    list = (*c->completer) (c, p, word);
+		  list = complete_line_internal_normal_command (tmp_command,
+								word, p,
+								reason, c);
 		}
 	    }
 	  else
@@ -945,24 +982,9 @@ complete_line_internal (const char *text,
 	  else
 	    {
 	      /* It is a normal command.  */
-	      if (c->completer == filename_completer)
-		{
-		  /* See the commentary above about the specifics
-		     of file-name completion.  */
-		  for (p = word;
-		       p > tmp_command
-			 && strchr (gdb_completer_file_name_break_characters, 
-				    p[-1]) == NULL;
-		       p--)
-		    ;
-		  set_rl_completer_word_break_characters
-		    (gdb_completer_file_name_break_characters);
-		}
-	      if (reason == handle_brkchars
-		  && c->completer_handle_brkchars != NULL)
-		(*c->completer_handle_brkchars) (c, p, word);
-	      if (reason != handle_brkchars && c->completer != NULL)
-		list = (*c->completer) (c, p, word);
+	      list = complete_line_internal_normal_command (tmp_command,
+							    word, p,
+							    reason, c);
 	    }
 	}
     }
@@ -1116,6 +1138,7 @@ complete_line (const char *text, const char *line_buffer, int point)
 }
 
 /* Complete on command names.  Used by "help".  */
+
 VEC (char_ptr) *
 command_completer (struct cmd_list_element *ignore, 
 		   const char *text, const char *word)
@@ -1124,6 +1147,16 @@ command_completer (struct cmd_list_element *ignore,
 				 strlen (text), handle_help);
 }
 
+/* The corresponding completer_handle_brkchars implementation.  */
+
+static void
+command_completer_handle_brkchars (struct cmd_list_element *ignore,
+				   const char *text, const char *word)
+{
+  set_rl_completer_word_break_characters
+    (gdb_completer_command_word_break_characters);
+}
+
 /* Complete on signals.  */
 
 VEC (char_ptr) *
@@ -1232,6 +1265,30 @@ reggroup_completer (struct cmd_list_element *ignore,
 				   complete_reggroup_names);
 }
 
+/* The default completer_handle_brkchars implementation.  */
+
+static void
+default_completer_handle_brkchars (struct cmd_list_element *ignore,
+				   const char *text, const char *word)
+{
+  set_rl_completer_word_break_characters
+    (current_language->la_word_break_characters ());
+}
+
+/* See definition in completer.h.  */
+
+completer_handle_brkchars_ftype *
+completer_handle_brkchars_func_for_completer (completer_ftype *fn)
+{
+  if (fn == filename_completer)
+    return filename_completer_handle_brkchars;
+
+  if (fn == command_completer)
+    return command_completer_handle_brkchars;
+
+  return default_completer_handle_brkchars;
+}
+
 /* Get the list of chars that are considered as word breaks
    for the current command.  */
 
diff --git a/gdb/completer.h b/gdb/completer.h
index 0a40eaa..463a53d 100644
--- a/gdb/completer.h
+++ b/gdb/completer.h
@@ -112,12 +112,14 @@ extern char *gdb_completion_word_break_characters (void);
    not "const char *".  */
 extern void set_rl_completer_word_break_characters (const char *break_chars);
 
-/* Set the word break characters array to the corresponding set of
-   chars, based on FN.  This function is useful for cases when the
-   completer doesn't know the type of the completion until some
+/* Get the matching completer_handle_brkchars_ftype function for FN.
+   FN is one of the core completer functions above (filename,
+   location, symbol, etc.).  This function is useful for cases when
+   the completer doesn't know the type of the completion until some
    calculation is done (e.g., for Python functions).  */
 
-extern void set_gdb_completion_word_break_characters (completer_ftype *fn);
+extern completer_handle_brkchars_ftype *
+  completer_handle_brkchars_func_for_completer (completer_ftype *fn);
 
 /* Exported to linespec.c */
 
diff --git a/gdb/python/py-cmd.c b/gdb/python/py-cmd.c
index 72ea577..b9a866e 100644
--- a/gdb/python/py-cmd.c
+++ b/gdb/python/py-cmd.c
@@ -293,11 +293,14 @@ cmdpy_completer_handle_brkchars (struct cmd_list_element *command,
 	}
       else if (value >= 0 && value < (long) N_COMPLETERS)
 	{
+	  completer_handle_brkchars_ftype *brkchars_fn;
+
 	  /* This is the core of this function.  Depending on which
 	     completer type the Python function returns, we have to
 	     adjust the break characters accordingly.  */
-	  set_gdb_completion_word_break_characters
-	    (completers[value].completer);
+	  brkchars_fn = (completer_handle_brkchars_func_for_completer
+			 (completers[value].completer));
+	  brkchars_fn (command, text, word);
 	}
     }
 }