commit 0f65ae0c36bf04e22219f28c32c3ae0cdee5acfe
Author: Dave Anderson <anderson@redhat.com>
Date:   Fri Dec 7 15:17:37 2018 -0500

    Implemented a new plugin function for the readline library's tab
    completion feature.  Without the patch, the use of the default plugin
    from the embedded gdb module has been seen to cause segmentation
    violations or other fatal malloc/free/corruption assertions.  The new
    plugin takes gdb out of the picture entirely, and also restricts the
    matching options to just symbol names, so as not to clutter the
    results with irrelevant filenames.
    (anderson@redhat.com)

diff --git a/cmdline.c b/cmdline.c
index cf3e150..665f48c 100644
--- a/cmdline.c
+++ b/cmdline.c
@@ -40,6 +40,8 @@ int shell_command(char *);
 static void modify_orig_line(char *, struct args_input_file *);
 static void modify_expression_arg(char *, char **, struct args_input_file *);
 static int verify_args_input_file(char *);
+static char *crash_readline_completion_generator(const char *, int);
+static char **crash_readline_completer(const char *, int, int);
 
 #define READLINE_LIBRARY
 
@@ -2073,6 +2075,9 @@ readline_init(void)
 	if (STREQ(pc->editing_mode, "emacs")) {
         	rl_editing_mode = emacs_mode;
 	}
+
+	rl_attempted_completion_function = crash_readline_completer;
+	rl_attempted_completion_over = 1;
 }
 
 /*
@@ -2610,3 +2615,27 @@ exec_args_input_file(struct command_table_entry *ct, struct args_input_file *aif
 	fclose(pc->args_ifile);
 	pc->args_ifile = NULL;
 }
+
+static char *
+crash_readline_completion_generator(const char *match, int state)
+{
+	static struct syment *sp_match;
+
+	if (state == 0)
+		sp_match = NULL;
+
+	sp_match = symbol_complete_match(match, sp_match);
+
+	if (sp_match)
+		return(strdup(sp_match->name));
+	else
+		return NULL;
+}
+
+static char **
+crash_readline_completer(const char *match, int start, int end)
+{
+	rl_attempted_completion_over = 1;
+	return rl_completion_matches(match, crash_readline_completion_generator);
+}
+
diff --git a/defs.h b/defs.h
index 9ce32c1..a3cb5a4 100644
--- a/defs.h
+++ b/defs.h
@@ -5153,6 +5153,7 @@ void parse_for_member_extended(struct datatype_member *, ulong);
 void add_to_downsized(char *);
 int is_downsized(char *);
 int is_string(char *, char *);
+struct syment *symbol_complete_match(const char *, struct syment *);
 
 /*  
  *  memory.c 
diff --git a/symbols.c b/symbols.c
index 05628ff..0769294 100644
--- a/symbols.c
+++ b/symbols.c
@@ -13108,3 +13108,73 @@ is_downsized(char *name)
 
 	return FALSE;
 }
+
+struct syment *
+symbol_complete_match(const char *match, struct syment *sp_last)
+{
+	int i;
+	struct syment *sp, *sp_end, *sp_start;
+	struct load_module *lm;
+	int search_init;
+
+	if (sp_last) {
+		sp_start = next_symbol(NULL, sp_last);
+		if (!sp_start)
+			return NULL;
+	} else	
+		sp_start = st->symtable;
+
+	if ((sp_start >= st->symtable) && (sp_start < st->symend)) {
+		for (sp = sp_start; sp < st->symend; sp++) {
+			if (STRNEQ(sp->name, match))
+				return sp;
+		}
+		sp_start = NULL;
+	}
+
+	search_init = FALSE;
+
+	for (i = 0; i < st->mods_installed; i++) {
+		lm = &st->load_modules[i];
+		if (lm->mod_flags & MOD_INIT)
+			search_init = TRUE;
+		sp_end = lm->mod_symend;
+		if (!sp_start)
+			sp_start = lm->mod_symtable;
+
+		if ((sp_start >= lm->mod_symtable) && (sp_start < sp_end)) {
+			for (sp = sp_start; sp < sp_end; sp++) {
+				if (MODULE_START(sp))
+					continue;
+	
+				if (STRNEQ(sp->name, match))
+					return sp;
+			}
+			sp_start = NULL;
+		}
+	}
+
+	if (!search_init)
+		return NULL;
+	
+	for (i = 0; i < st->mods_installed; i++) {
+		lm = &st->load_modules[i];
+		if (!lm->mod_init_symtable)
+			continue;
+		sp_end = lm->mod_init_symend;
+		if (!sp_start)
+			sp_start = lm->mod_init_symtable;
+
+		if ((sp_start >= lm->mod_init_symtable) && (sp_start < sp_end)) {
+			for (sp = sp_start; sp < sp_end; sp++) {
+				if (MODULE_START(sp))
+					continue;
+	
+				if (STRNEQ(sp->name, match))
+					return sp;
+			}
+		}
+	}
+
+	return NULL;
+}