gdbmtool: rewrite handler parameter functions; fix memory leaks

* src/input-null.c: New file.
* src/Makefile.am: Add input-null.c
* src/mem.c (e2nrealloc): New function.
* src/gdbmapp.h (e2nrealloc): New proto.
* src/gdbmtool.c (quit_handler): Exit from parser instead of
exiting from the program.
(param): Remove global.
(param_expand,param_push_arg,param_free): New functions for
handling parameters.
(param_free_argv): Take a single argument.  Clear all
parameters up to argc.
(run_command): Rewrite parameter handling using new functions.
(main): Call input_init() after the input stream has been set
up.
Call yylex_destroy when finished.
* src/gdbmtool.h (instream_null_create): New proto.
(handler_param): Change type of argc to size_t.  New field
argmax.
(HANDLER_PARAM_INITIALIZER): New define.
(yylex_destroy): New proto.
* src/input-rl.c (history_file_name): New static.
(get_history_file_name): Initialize history_file_name.
(input_init): Initialize input history only in interactive mode.
(input_done): Free input history only in interactive mode.

7 files changed, 168 insertions, 52 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 0d10f23..fa08bf3 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -100,6 +100,7 @@ gdbmtool_SOURCES = \
  gram.y\
  input-argv.c\
  input-file.c\
+ input-null.c\
  lex.l\
  gdbmtool.h\
  gdbmtool.c\
diff --git a/src/gdbmapp.h b/src/gdbmapp.h
index 06d1cea..5c60e7b 100644
--- a/src/gdbmapp.h
+++ b/src/gdbmapp.h
@@ -34,6 +34,7 @@ void *erealloc (void *ptr, size_t size);
 void *ecalloc (size_t nmemb, size_t size);
 void *ezalloc (size_t size);
 char *estrdup (const char *str);
+void *e2nrealloc (void *p, size_t *pn, size_t s);
 
 #define PARSEOPT_HIDDEN 0x01
 #define PARSEOPT_ALIAS  0x02
diff --git a/src/gdbmtool.c b/src/gdbmtool.c
index 61d81a9..2c1f469 100644
--- a/src/gdbmtool.c
+++ b/src/gdbmtool.c
@@ -1165,9 +1165,10 @@ list_handler (struct handler_param *param)
 void
 quit_handler (struct handler_param *param GDBM_ARG_UNUSED)
 {
-  closedb ();
-  input_done ();
-  exit (EXIT_OK);
+  while (!input_context_pop ())
+    ;
+  if (input_context_push (instream_null_create ()))
+    exit (EXIT_FATAL);
 }
 
 /* export FILE [truncate] - export to a flat file format */
@@ -1871,8 +1872,6 @@ struct gdbm_option optab[] = {
   { 0 }
 };
 
-#define ARGINC 16
-
 
 struct gdbmarg *
 gdbmarg_string (char *string, struct locus *loc)
@@ -2082,18 +2081,53 @@ gdbmarglist_free (struct gdbmarglist *lst)
   lst->head = lst->tail = NULL;
 }
 
-struct handler_param param;
-size_t argmax;
+static void
+param_expand (struct handler_param *p)
+{
+  if (p->argc == p->argmax)
+    p->argv = e2nrealloc (p->argv, &p->argmax, sizeof (p->argv[0]));
+}
 
-void
-param_free_argv (struct handler_param *p, int n)
+static void
+param_free_argv (struct handler_param *p)
 {
-  int i;
+  size_t i;
 
-  for (i = 0; i < n; i++)
+  for (i = 0; i < p->argc; i++)
     gdbmarg_destroy (&p->argv[i]);
   p->argc = 0;
 }
+
+static void
+param_free (struct handler_param *p)
+{
+  param_free_argv (p);
+  free (p->argv);
+  p->argv = NULL;
+  p->argmax = 0;
+}
+
+static struct gdbmarg *coerce (struct gdbmarg *arg, struct argdef *def);
+
+static int
+param_push_arg (struct handler_param *p, struct gdbmarg *arg,
+		struct argdef *def)
+{
+  param_expand (p);
+  if ((p->argv[p->argc] = coerce (arg, def)) == NULL)
+    {
+      return 1;
+    }
+  p->argc++;
+  return 0;
+}
+
+static void
+param_term (struct handler_param *p)
+{
+  param_expand (p);
+  p->argv[p->argc] = NULL;
+}
 
 typedef struct gdbmarg *(*coerce_type_t) (struct gdbmarg *arg,
 					  struct argdef *def);
@@ -2141,7 +2175,7 @@ coerce_type_t coerce_tab[GDBM_ARG_MAX][GDBM_ARG_MAX] = {
 
 char *argtypestr[] = { "string", "datum", "k/v pair" };
   
-struct gdbmarg *
+static struct gdbmarg *
 coerce (struct gdbmarg *arg, struct argdef *def)
 {
   if (!coerce_tab[def->type][arg->type])
@@ -2190,22 +2224,17 @@ run_command (struct command *cmd, struct gdbmarglist *arglist)
   char argbuf[128];
   size_t expected_lines, *expected_lines_ptr;
   FILE *pagfp = NULL;
-
+  struct handler_param param = HANDLER_PARAM_INITIALIZER;
+    
   variable_get ("pager", VART_STRING, (void**) &pager);
   
   arg = arglist ? arglist->head : NULL;
 
   for (i = 0; cmd->args[i].name && arg; i++, arg = arg->next)
     {
-      if (i >= argmax)
-	{
-	  argmax += ARGINC;
-	  param.argv = erealloc (param.argv,
-				 sizeof (param.argv[0]) * argmax);
-	}
-      if ((param.argv[i] = coerce (arg, &cmd->args[i])) == NULL)
+      if (param_push_arg (&param, arg, &cmd->args[i]))
 	{
-	  param_free_argv (&param, i);
+	  param_free (&param);
 	  return 1;
 	}
     }
@@ -2222,6 +2251,7 @@ run_command (struct command *cmd, struct gdbmarglist *arglist)
       if (!interactive ())
 	{
 	  terror (_("%s: not enough arguments"), cmd->name);
+	  param_free (&param);
 	  return 1;
 	}
       printf ("%s? ", argname);
@@ -2233,18 +2263,12 @@ run_command (struct command *cmd, struct gdbmarglist *arglist)
 	}
 
       trimnl (argbuf);
-      if (i >= argmax)
-	{
-	  argmax += ARGINC;
-	  param.argv = erealloc (param.argv,
-				 sizeof (param.argv[0]) * argmax);
-	}
-
+      
       t = gdbmarg_string (estrdup (argbuf), &yylloc);
-      if ((param.argv[i] = coerce (t, &cmd->args[i])) == NULL)
+      if (param_push_arg (&param, t, &cmd->args[i]))
 	{
+	  param_free (&param);
 	  gdbmarg_free (t);
-	  param_free_argv (&param, i);
 	  return 1;
 	}
     }
@@ -2252,17 +2276,12 @@ run_command (struct command *cmd, struct gdbmarglist *arglist)
   if (arg && !cmd->variadic)
     {
       terror (_("%s: too many arguments"), cmd->name);
+      param_free (&param);
       return 1;
     }
 
   /* Prepare for calling the handler */
-  param.argc = i;
-  if (!param.argv)
-    {
-      argmax = ARGINC;
-      param.argv = ecalloc (argmax, sizeof (param.argv[0]));
-    }
-  param.argv[i] = NULL;
+  param_term (&param);
   param.vararg = arg;
   param.fp = NULL;
   param.data = NULL;
@@ -2298,8 +2317,8 @@ run_command (struct command *cmd, struct gdbmarglist *arglist)
 	pclose (pagfp);
     }
 
-  param_free_argv (&param, param.argc);
-
+  param_free (&param);
+  
   last_cmd = cmd;
   if (arglist->head != last_args.head)
     {
@@ -2391,7 +2410,6 @@ main (int argc, char *argv[])
   variable_set ("open", VART_STRING, "wrcreat");
   variable_set ("pager", VART_STRING, getenv ("PAGER"));
   
-  input_init ();
   lex_trace (0);
   
   for (opt = parseopt_first (argc, argv, optab);
@@ -2504,15 +2522,14 @@ main (int argc, char *argv[])
 
   signal (SIGPIPE, SIG_IGN);
 
-  memset (&param, 0, sizeof (param));
-  argmax = 0;
-
   if (!norc)
     source_rcfile ();
 
   if (!input)
     input = instream_stdin_create ();
   
+  input_init ();
+
   /* Welcome message. */
   if (instream_interactive (input) && !variable_is_true ("quiet"))
     printf (_("\nWelcome to the gdbm tool.  Type ? for help.\n\n"));
@@ -2520,7 +2537,8 @@ main (int argc, char *argv[])
   if (input_context_push (input))
     exit (EXIT_FATAL);
   res = yyparse ();
-  closedb ();
+  yylex_destroy ();
   input_done ();
+  closedb ();
   return res;
 }
diff --git a/src/gdbmtool.h b/src/gdbmtool.h
index 14245e8..c753871 100644
--- a/src/gdbmtool.h
+++ b/src/gdbmtool.h
@@ -165,9 +165,11 @@ void input_done (void);
 instream_t instream_stdin_create (void);
 instream_t instream_argv_create (int argc, char **argv);
 instream_t instream_file_create (char const *name);
+instream_t instream_null_create (void);
 
 int interactive (void);
 int input_context_push (instream_t);
+int input_context_pop (void);
 
 struct handler_param;
 void input_history_handler (struct handler_param *param);
@@ -239,13 +241,16 @@ struct gdbmarglist
 
 struct handler_param
 {
-  int argc;
+  size_t argc;
+  size_t argmax;
   struct gdbmarg **argv;
   struct gdbmarg *vararg;
   FILE *fp;
   void *data;
 };
 
+#define HANDLER_PARAM_INITIALIZER { 0, 0, NULL, NULL, NULL, NULL }
+
 #define PARAM_STRING(p,n) ((p)->argv[n]->v.string)
 #define PARAM_DATUM(p,n)  ((p)->argv[n]->v.dat)
 #define PARAM_KVPAIR(p,n) ((p)->argv[n]->v.kvpair)
@@ -342,6 +347,7 @@ void begin_def (void);
 void end_def (void);
 
 int yylex (void);
+int yylex_destroy (void);
 int yyerror (char const *s);
 int yyparse (void);
 
diff --git a/src/input-null.c b/src/input-null.c
new file mode 100644
index 0000000..265abb8
--- /dev/null
+++ b/src/input-null.c
@@ -0,0 +1,51 @@
+/* This file is part of GDBM, the GNU data base manager.
+   Copyright (C) 2018-2021 Free Software Foundation, Inc.
+
+   GDBM is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3, or (at your option)
+   any later version.
+
+   GDBM is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with GDBM. If not, see <http://www.gnu.org/licenses/>.    */
+
+#include "gdbmtool.h"
+
+static ssize_t
+instream_null_read (instream_t istr, char *buf, size_t size)
+{
+  return 0;
+}
+
+static void
+instream_null_close (instream_t istr)
+{
+  free (istr);
+}
+
+static int
+instream_null_eq (instream_t a, instream_t b)
+{
+  return a == b;
+}
+
+instream_t
+instream_null_create (void)
+{
+  struct instream *istr;
+
+  istr = emalloc (sizeof *istr);
+  istr->in_name = "null";
+  istr->in_inter = 0;
+  istr->in_read = instream_null_read;
+  istr->in_close = instream_null_close;
+  istr->in_eq = instream_null_eq;
+
+  return istr;
+}
+
diff --git a/src/input-rl.c b/src/input-rl.c
index 1f361dd..e530b9c 100644
--- a/src/input-rl.c
+++ b/src/input-rl.c
@@ -122,12 +122,12 @@ input_history_handler (struct handler_param *param)
 #define HISTFILE_PREFIX "~/."
 #define HISTFILE_SUFFIX "_history"
 
+static char *history_file_name;
+
 static char *
 get_history_file_name (void)
 {
-  static char *filename = NULL;
-
-  if (!filename)
+  if (!history_file_name)
     {
       char *hname;
 
@@ -136,10 +136,10 @@ get_history_file_name (void)
       strcpy (hname, HISTFILE_PREFIX);
       strcat (hname, rl_readline_name);
       strcat (hname, HISTFILE_SUFFIX);
-      filename = tildexpand (hname);
+      history_file_name = tildexpand (hname);
       free (hname);
     }
-  return filename;
+  return history_file_name;
 }
  
 static char **
@@ -165,13 +165,19 @@ input_init (void)
   rl_readline_name = (char *) progname;
   rl_attempted_completion_function = shell_completion;
   rl_pre_input_hook = pre_input;
-  read_history (get_history_file_name ());
+  if (interactive ())
+    read_history (get_history_file_name ());
 }
 
 void
 input_done (void)
 {
-  write_history (get_history_file_name ());
+  if (history_file_name)
+    {
+      write_history (history_file_name);
+      free (history_file_name);
+      history_file_name = NULL;
+    }
 }
 
 static void
diff --git a/src/mem.c b/src/mem.c
index bfbeafc..8b2da75 100644
--- a/src/mem.c
+++ b/src/mem.c
@@ -71,4 +71,37 @@ estrdup (const char *str)
   return p;
 }
 
+void *
+e2nrealloc (void *p, size_t *pn, size_t s)
+{
+  size_t n = *pn;
+  char *newp;
+	
+  if (!p)
+    {
+      if (!n)
+	{
+	  /* The approximate size to use for initial small
+	     allocation requests, when the invoking code
+	     specifies an old size of zero.  64 bytes is
+	     the largest "small" request for the
+	     GNU C library malloc.  */
+	  enum { DEFAULT_MXFAST = 64 };
+	  
+	  n = DEFAULT_MXFAST / s;
+	  n += !n;
+	}
+    }
+  else if ((size_t) -1 / 3 * 2 / s <= n)
+    {
+      ealloc_die ();
+    }
+  else
+    n += (n + 1) / 2;
+
+  newp = erealloc (p, n * s);
+  *pn = n;
+  return newp;
+}
+