lib/command.c: rewrite command matching/parsing

Add support for keyword commands.

Includes new documentation for DEFUN() in lib/command.h, for preexisting
features as well as new keyword specification.

Signed-off-by: Christian Franke <chris@opensourcerouting.org>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

babeld/babel_main.c

@@ -277,9 +277,6 @@ babel_init(int argc, char **argv)
     /* this replace kernel_setup && kernel_setup_socket */
     babelz_zebra_init ();
 
-    /* Sort all installed commands. */
-    sort_node ();
-
     /* Get zebra configuration file. */
     zlog_set_level (NULL, ZLOG_DEST_STDOUT, ZLOG_DISABLED);
     vty_read_config (babel_config_file, babel_config_default);

bgpd/bgp_main.c

@@ -431,9 +431,6 @@ main (int argc, char **argv)
   /* BGP related initialization.  */
   bgp_init ();
 
-  /* Sort CLI commands. */
-  sort_node ();
-
   /* Parse config file. */
   vty_read_config (config_file, config_default);
 

isisd/isis_main.c

@@ -339,8 +339,6 @@ main (int argc, char **argv, char **envp)
 
   isis_zebra_init ();
 
-  sort_node ();
-
   /* parse config file */
   /* this is needed three times! because we have interfaces before the areas */
   vty_read_config (config_file, config_default);

lib/command.h

@@ -138,18 +138,32 @@ struct cmd_element
   int (*func) (struct cmd_element *, struct vty *, int, const char *[]);
   const char *doc;			/* Documentation of this command. */
   int daemon;                   /* Daemon to which this command belong. */
-  vector strvec;		/* Pointing out each description vector. */
+  vector tokens;		/* Vector of cmd_tokens */
-  unsigned int cmdsize;		/* Command index count. */
-  char *config;			/* Configuration string */
-  vector subconfig;		/* Sub configuration string */
   u_char attr;			/* Command attributes */
 };
 
-/* Command description structure. */
+
-struct desc
+enum cmd_token_type
 {
+  TOKEN_TERMINAL = 0,
+  TOKEN_MULTIPLE,
+  TOKEN_KEYWORD,
+};
+
+/* Command description structure. */
+struct cmd_token
+{
+  enum cmd_token_type type;
+
+  /* Used for type == MULTIPLE */
+  vector multiple; /* vector of cmd_token, type == FINAL */
+
+  /* Used for type == KEYWORD */
+  vector keyword; /* vector of vector of cmd_tokens */
+
+  /* Used for type == TERMINAL */
   char *cmd;                    /* Command string. */
-  char *str;                    /* Command's description. */
+  char *desc;                    /* Command's description. */
 };
 
 /* Return value of the commands. */
@@ -192,7 +206,170 @@ struct desc
      int argc __attribute__ ((unused)), \
      const char *argv[] __attribute__ ((unused)) )
 
-/* DEFUN for vty command interafce. Little bit hacky ;-). */
+/* DEFUN for vty command interafce. Little bit hacky ;-).
+ *
+ * DEFUN(funcname, cmdname, cmdstr, helpstr)
+ *
+ * funcname
+ * ========
+ *
+ * Name of the function that will be defined.
+ *
+ * cmdname
+ * =======
+ *
+ * Name of the struct that will be defined for the command.
+ *
+ * cmdstr
+ * ======
+ *
+ * The cmdstr defines the command syntax. It is used by the vty subsystem
+ * and vtysh to perform matching and completion in the cli. So you have to take
+ * care to construct it adhering to the following grammar. The names used
+ * for the production rules losely represent the names used in lib/command.c
+ *
+ * cmdstr = cmd_token , { " " , cmd_token } ;
+ *
+ * cmd_token = cmd_terminal
+ *           | cmd_multiple
+ *           | cmd_keyword ;
+ *
+ * cmd_terminal_fixed = fixed_string
+ *                    | variable
+ *                    | range
+ *                    | ipv4
+ *                    | ipv4_prefix
+ *                    | ipv6
+ *                    | ipv6_prefix ;
+ *
+ * cmd_terminal = cmd_terminal_fixed
+ *              | option
+ *              | vararg ;
+ *
+ * multiple_part = cmd_terminal_fixed ;
+ * cmd_multiple = "(" , multiple_part , ( "|" | { "|" , multiple_part } ) , ")" ;
+ *
+ * keyword_part = fixed_string , { " " , ( cmd_terminal_fixed | cmd_multiple ) } ;
+ * cmd_keyword = "{" , keyword_part , { "|" , keyword_part } , "}" ;
+ *
+ * lowercase = "a" | ... | "z" ;
+ * uppercase = "A" | ... | "Z" ;
+ * digit = "0" | ... | "9" ;
+ * number = digit , { digit } ;
+ *
+ * fixed_string = (lowercase | digit) , { lowercase | digit | uppercase | "-" | "_" } ;
+ * variable = uppercase , { uppercase | "_" } ;
+ * range = "<" , number , "-" , number , ">" ;
+ * ipv4 = "A.B.C.D" ;
+ * ipv4_prefix = "A.B.C.D/M" ;
+ * ipv6 = "X:X::X:X" ;
+ * ipv6_prefix = "X:X::X:X/M" ;
+ * option = "[" , variable , "]" ;
+ * vararg = "." , variable ;
+ *
+ * To put that all in a textual description: A cmdstr is a sequence of tokens,
+ * separated by spaces.
+ *
+ * Terminal Tokens:
+ *
+ * A very simple cmdstring would be something like: "show ip bgp". It consists
+ * of three Terminal Tokens, each containing a fixed string. When this command
+ * is called, no arguments will be passed down to the function implementing it,
+ * as it only consists of fixed strings.
+ *
+ * Apart from fixed strings, Terminal Tokens can also contain variables:
+ * An example would be "show ip bgp A.B.C.D". This command expects an IPv4
+ * as argument. As this is a variable, the IP address entered by the user will
+ * be passed down as an argument. Apart from two exceptions, the other options
+ * for Terminal Tokens behave exactly as we just discussed and only make a
+ * difference for the CLI. The two exceptions will be discussed in the next
+ * paragraphs.
+ *
+ * A Terminal Token can contain a so called option match. This is a simple
+ * string variable that the user may omit. An example would be:
+ * "show interface [IFNAME]". If the user calls this without an interface as
+ * argument, no arguments will be passed down to the function implementing
+ * this command. Otherwise, the interface name will be provided to the function
+ * as a regular argument.
+
+ * Also, a Terminal Token can contain a so called vararg. This is used e.g. in
+ * "show ip bgp regexp .LINE". The last token is a vararg match and will
+ * consume all the arguments the user inputs on the command line and append
+ * those to the list of arguments passed down to the function implementing this
+ * command. (Therefore, it doesn't make much sense to have any tokens after a
+ * vararg because the vararg will already consume all the words the user entered
+ * in the CLI)
+ *
+ * Multiple Tokens:
+ *
+ * The Multiple Token type can be used if there are multiple possibilities what
+ * arguments may be used for a command, but it should map to the same function
+ * nonetheless. An example would be "ip route A.B.C.D/M (reject|blackhole)"
+ * In that case both "reject" and "blackhole" would be acceptable as last
+ * arguments. The words matched by Multiple Tokens are always added to the
+ * argument list, even if they are matched by fixed strings. Such a Multiple
+ * Token can contain almost any type of token that would also be acceptable
+ * for a Terminal Token, the exception are optional variables and varag.
+ *
+ * There is one special case that is used in some places of Quagga that should be
+ * pointed out here shortly. An example would be "password (8|) WORD". This
+ * construct is used to have fixed strings communicated as arguments. (The "8"
+ * will be passed down as an argument in this case) It does not mean that
+ * the "8" is optional. Another historic and possibly surprising property of
+ * this construct is that it consumes two parts of helpstr. (Help
+ * strings will be explained later)
+ *
+ * Keyword Tokens:
+ *
+ * There are commands that take a lot of different and possibly optional arguments.
+ * An example from ospf would be the "default-information originate" command. This
+ * command takes a lot of optional arguments that may be provided in any order.
+ * To accomodate such commands, the Keyword Token has been implemented.
+ * Using the keyword token, the "default-information originate" command and all
+ * its possible options can be represented using this single cmdstr:
+ * "default-information originate \
+ *  {always|metric <0-16777214>|metric-type (1|2)|route-map WORD}"
+ *
+ * Keywords always start with a fixed string and may be followed by arguments.
+ * Except optional variables and vararg, everything is permitted here.
+ *
+ * For the special case of a keyword without arguments, either NULL or the
+ * keyword itself will be pushed as an argument, depending on whether the
+ * keyword is present.
+ * For the other keywords, arguments will be only pushed for
+ * variables/Multiple Tokens. If the keyword is not present, the arguments that
+ * would have been pushed will be substituted by NULL.
+ *
+ * A few examples:
+ *   "default information originate metric-type 1 metric 1000"
+ * would yield the following arguments:
+ *   { NULL, "1000", "1", NULL }
+ *
+ *   "default information originate always route-map RMAP-DEFAULT"
+ * would yield the following arguments:
+ *   { "always", NULL, NULL, "RMAP-DEFAULT" }
+ *
+ * helpstr
+ * =======
+ *
+ * The helpstr is used to show a short explantion for the commands that
+ * are available when the user presses '?' on the CLI. It is the concatenation
+ * of the helpstrings for all the tokens that make up the command.
+ *
+ * There should be one helpstring for each token in the cmdstr except those
+ * containing other tokens, like Multiple or Keyword Tokens. For those, there
+ * will only be the helpstrings of the contained tokens.
+ *
+ * The individual helpstrings are expected to be in the same order as their
+ * respective Tokens appear in the cmdstr. They should each be terminated with
+ * a linefeed. The last helpstring should be terminated with a linefeed as well.
+ *
+ * Care should also be taken to avoid having similar tokens with different
+ * helpstrings. Imagine e.g. the commands "show ip ospf" and "show ip bgp".
+ * they both contain a helpstring for "show", but only one will be displayed
+ * when the user enters "sh?". If those two helpstrings differ, it is not
+ * defined which one will be shown and the behavior is therefore unpredictable.
+ */
 #define DEFUN(funcname, cmdname, cmdstr, helpstr) \
   DEFUN_CMD_FUNC_DECL(funcname) \
   DEFUN_CMD_ELEMENT(funcname, cmdname, cmdstr, helpstr, 0, 0) \
@@ -330,7 +507,6 @@ struct desc
 extern void install_node (struct cmd_node *, int (*) (struct vty *));
 extern void install_default (enum node_type);
 extern void install_element (enum node_type, struct cmd_element *);
-extern void sort_node (void);
 
 /* Concatenates argv[shift] through argv[argc-1] into a single NUL-terminated
    string with a space between each element (allocated using
@@ -346,7 +522,6 @@ extern int config_from_file (struct vty *, FILE *);
 extern enum node_type node_parent (enum node_type);
 extern int cmd_execute_command (vector, struct vty *, struct cmd_element **, int);
 extern int cmd_execute_command_strict (vector, struct vty *, struct cmd_element **);
-extern void config_replace_string (struct cmd_element *, char *, ...);
 extern void cmd_init (int);
 extern void cmd_terminate (void);
 

lib/memtypes.c

@@ -54,7 +54,7 @@ struct memory_list memory_list_lib[] =
   { MTYPE_ROUTE_MAP_RULE,	"Route map rule"		},
   { MTYPE_ROUTE_MAP_RULE_STR,	"Route map rule str"		},
   { MTYPE_ROUTE_MAP_COMPILED,	"Route map compiled"		},
-  { MTYPE_DESC,			"Command desc"			},
+  { MTYPE_CMD_TOKENS,		"Command desc"			},
   { MTYPE_KEY,			"Key"				},
   { MTYPE_KEYCHAIN,		"Key chain"			},
   { MTYPE_IF_RMAP,		"Interface route map"		},

lib/vty.c

@@ -931,23 +931,23 @@ vty_complete_command (struct vty *vty)
 
 static void
 vty_describe_fold (struct vty *vty, int cmd_width,
-		   unsigned int desc_width, struct desc *desc)
+		   unsigned int desc_width, struct cmd_token *token)
 {
   char *buf;
   const char *cmd, *p;
   int pos;
 
-  cmd = desc->cmd[0] == '.' ? desc->cmd + 1 : desc->cmd;
+  cmd = token->cmd[0] == '.' ? token->cmd + 1 : token->cmd;
 
   if (desc_width <= 0)
     {
-      vty_out (vty, "  %-*s  %s%s", cmd_width, cmd, desc->str, VTY_NEWLINE);
+      vty_out (vty, "  %-*s  %s%s", cmd_width, cmd, token->desc, VTY_NEWLINE);
       return;
     }
 
-  buf = XCALLOC (MTYPE_TMP, strlen (desc->str) + 1);
+  buf = XCALLOC (MTYPE_TMP, strlen (token->desc) + 1);
 
-  for (p = desc->str; strlen (p) > desc_width; p += pos + 1)
+  for (p = token->desc; strlen (p) > desc_width; p += pos + 1)
     {
       for (pos = desc_width; pos > 0; pos--)
       if (*(p + pos) == ' ')
@@ -976,7 +976,7 @@ vty_describe_command (struct vty *vty)
   vector vline;
   vector describe;
   unsigned int i, width, desc_width;
-  struct desc *desc, *desc_cr = NULL;
+  struct cmd_token *token, *token_cr = NULL;
 
   vline = cmd_make_strvec (vty->buf);
 
@@ -1010,15 +1010,15 @@ vty_describe_command (struct vty *vty)
   /* Get width of command string. */
   width = 0;
   for (i = 0; i < vector_active (describe); i++)
-    if ((desc = vector_slot (describe, i)) != NULL)
+    if ((token = vector_slot (describe, i)) != NULL)
       {
 	unsigned int len;
 
-	if (desc->cmd[0] == '\0')
+	if (token->cmd[0] == '\0')
 	  continue;
 
-	len = strlen (desc->cmd);
+	len = strlen (token->cmd);
-	if (desc->cmd[0] == '.')
+	if (token->cmd[0] == '.')
 	  len--;
 
 	if (width < len)
@@ -1030,27 +1030,27 @@ vty_describe_command (struct vty *vty)
 
   /* Print out description. */
   for (i = 0; i < vector_active (describe); i++)
-    if ((desc = vector_slot (describe, i)) != NULL)
+    if ((token = vector_slot (describe, i)) != NULL)
       {
-	if (desc->cmd[0] == '\0')
+	if (token->cmd[0] == '\0')
 	  continue;
 	
-	if (strcmp (desc->cmd, command_cr) == 0)
+	if (strcmp (token->cmd, command_cr) == 0)
 	  {
-	    desc_cr = desc;
+	    token_cr = token;
 	    continue;
 	  }
 
-	if (!desc->str)
+	if (!token->desc)
 	  vty_out (vty, "  %-s%s",
-		   desc->cmd[0] == '.' ? desc->cmd + 1 : desc->cmd,
+		   token->cmd[0] == '.' ? token->cmd + 1 : token->cmd,
 		   VTY_NEWLINE);
-	else if (desc_width >= strlen (desc->str))
+	else if (desc_width >= strlen (token->desc))
 	  vty_out (vty, "  %-*s  %s%s", width,
-		   desc->cmd[0] == '.' ? desc->cmd + 1 : desc->cmd,
+		   token->cmd[0] == '.' ? token->cmd + 1 : token->cmd,
-		   desc->str, VTY_NEWLINE);
+		   token->desc, VTY_NEWLINE);
 	else
-	  vty_describe_fold (vty, width, desc_width, desc);
+	  vty_describe_fold (vty, width, desc_width, token);
 
 #if 0
 	vty_out (vty, "  %-*s %s%s", width
@@ -1059,18 +1059,18 @@ vty_describe_command (struct vty *vty)
 #endif /* 0 */
       }
 
-  if ((desc = desc_cr))
+  if ((token = token_cr))
     {
-      if (!desc->str)
+      if (!token->desc)
 	vty_out (vty, "  %-s%s",
-		 desc->cmd[0] == '.' ? desc->cmd + 1 : desc->cmd,
+		 token->cmd[0] == '.' ? token->cmd + 1 : token->cmd,
 		 VTY_NEWLINE);
-      else if (desc_width >= strlen (desc->str))
+      else if (desc_width >= strlen (token->desc))
 	vty_out (vty, "  %-*s  %s%s", width,
-		 desc->cmd[0] == '.' ? desc->cmd + 1 : desc->cmd,
+		 token->cmd[0] == '.' ? token->cmd + 1 : token->cmd,
-		 desc->str, VTY_NEWLINE);
+		 token->desc, VTY_NEWLINE);
       else
-	vty_describe_fold (vty, width, desc_width, desc);
+	vty_describe_fold (vty, width, desc_width, token);
     }
 
 out:

ospf6d/ospf6_main.c

@@ -325,9 +325,6 @@ main (int argc, char *argv[], char *envp[])
   /* initialize ospf6 */
   ospf6_init ();
 
-  /* sort command vector */
-  sort_node ();
-
   /* parse config file */
   vty_read_config (config_file, config_default);
 

ospfd/ospf_main.c

@@ -310,8 +310,6 @@ main (int argc, char **argv)
   ospf_opaque_init ();
 #endif /* HAVE_OPAQUE_LSA */
   
-  sort_node ();
-
   /* Get configuration file. */
   vty_read_config (config_file, config_default);
 

ripd/rip_main.c

@@ -287,9 +287,6 @@ main (int argc, char **argv)
   rip_zclient_init ();
   rip_peer_init ();
 
-  /* Sort all installed commands. */
-  sort_node ();
-
   /* Get configuration file. */
   vty_read_config (config_file, config_default);
 

ripngd/ripng_main.c

@@ -282,9 +282,6 @@ main (int argc, char **argv)
   zebra_init ();
   ripng_peer_init ();
 
-  /* Sort all installed commands. */
-  sort_node ();
-
   /* Get configuration file. */
   vty_read_config (config_file, config_default);
 

tests/main.c

@@ -171,8 +171,6 @@ main (int argc, char **argv)
   /* OSPF vty inits. */
   test_vty_init ();
 
-  sort_node ();
-
   /* Change to the daemon program. */
   if (daemon_mode && daemon (0, 0) < 0)
     {

tests/test-commands.c

@@ -233,8 +233,6 @@ test_init(void)
             cmd->daemon = 0;
             cmd->func = test_callback;
           }
-  sort_node();
-
   test_load();
   vty_init_vtysh();
 }
@@ -340,8 +338,8 @@ test_run(struct prng *prng, struct vty *vty, const char *cmd, unsigned int edit_
           {
             for (j = 0; j < vector_active(descriptions); j++)
               {
-                struct desc *cmd = vector_slot(descriptions, j);
+                struct cmd_token *cmd = vector_slot(descriptions, j);
-                printf("  '%s' '%s'\n", cmd->cmd, cmd->str);
+                printf("  '%s' '%s'\n", cmd->cmd, cmd->desc);
               }
             vector_free(descriptions);
           }

vtysh/vtysh.c

@@ -554,7 +554,7 @@ vtysh_rl_describe (void)
   vector vline;
   vector describe;
   int width;
-  struct desc *desc;
+  struct cmd_token *token;
 
   vline = cmd_make_strvec (rl_line_buffer);
 
@@ -592,15 +592,15 @@ vtysh_rl_describe (void)
   /* Get width of command string. */
   width = 0;
   for (i = 0; i < vector_active (describe); i++)
-    if ((desc = vector_slot (describe, i)) != NULL)
+    if ((token = vector_slot (describe, i)) != NULL)
       {
 	int len;
 
-	if (desc->cmd[0] == '\0')
+	if (token->cmd[0] == '\0')
 	  continue;
 
-	len = strlen (desc->cmd);
+	len = strlen (token->cmd);
-	if (desc->cmd[0] == '.')
+	if (token->cmd[0] == '.')
 	  len--;
 
 	if (width < len)
@@ -608,19 +608,19 @@ vtysh_rl_describe (void)
       }
 
   for (i = 0; i < vector_active (describe); i++)
-    if ((desc = vector_slot (describe, i)) != NULL)
+    if ((token = vector_slot (describe, i)) != NULL)
       {
-	if (desc->cmd[0] == '\0')
+	if (token->cmd[0] == '\0')
 	  continue;
 
-	if (! desc->str)
+	if (! token->desc)
 	  fprintf (stdout,"  %-s\n",
-		   desc->cmd[0] == '.' ? desc->cmd + 1 : desc->cmd);
+		   token->cmd[0] == '.' ? token->cmd + 1 : token->cmd);
 	else
 	  fprintf (stdout,"  %-*s  %s\n",
 		   width,
-		   desc->cmd[0] == '.' ? desc->cmd + 1 : desc->cmd,
+		   token->cmd[0] == '.' ? token->cmd + 1 : token->cmd,
-		   desc->str);
+		   token->desc);
       }
 
   cmd_free_strvec (vline);

vtysh/vtysh_main.c

@@ -299,8 +299,6 @@ main (int argc, char **argv, char **env)
 
   vty_init_vtysh ();
 
-  sort_node ();
-
   /* Read vtysh configuration file before connecting to daemons. */
   vtysh_read_config (config_default);
 

zebra/main.c

@@ -343,9 +343,6 @@ main (int argc, char **argv)
   interface_list ();
   route_read ();
 
-  /* Sort VTY commands. */
-  sort_node ();
-
 #ifdef HAVE_SNMP
   zebra_snmp_init ();
 #endif /* HAVE_SNMP */

zebra/test_main.c

@@ -298,9 +298,6 @@ main (int argc, char **argv)
   route_read ();
   zebra_vty_init();
 
-  /* Sort VTY commands. */
-  sort_node ();
-
   /* Configuration file read*/
   vty_read_config (config_file, config_default);