gdb/cli/cli-script.c - gdb

Global variables defined

Data types defined

Functions defined

Macros defined

Source code

  1. /* GDB CLI command scripting.

  3.    Copyright (C) 1986-2015 Free Software Foundation, Inc.

  5.    This file is part of GDB.

  7.    This program is free software; you can redistribute it and/or modify
  8.    it under the terms of the GNU General Public License as published by
  9.    the Free Software Foundation; either version 3 of the License, or
  10.    (at your option) any later version.

  12.    This program is distributed in the hope that it will be useful,
  13.    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14.    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15.    GNU General Public License for more details.

  17.    You should have received a copy of the GNU General Public License
  18.    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

  20. #include "defs.h"
  21. #include "value.h"
  22. #include "language.h"                /* For value_true */
  23. #include <ctype.h>

  25. #include "ui-out.h"
  26. #include "top.h"
  27. #include "breakpoint.h"
  28. #include "cli/cli-cmds.h"
  29. #include "cli/cli-decode.h"
  30. #include "cli/cli-script.h"

  32. #include "extension.h"
  33. #include "interps.h"
  34. #include "compile/compile.h"

  36. /* Prototypes for local functions.  */

  38. static enum command_control_type
  39. recurse_read_control_structure (char * (*read_next_line_func) (void),
  40.                                 struct command_line *current_cmd,
  41.                                 void (*validator)(char *, void *),
  42.                                 void *closure);

  44. static char *insert_args (char *line);

  46. static struct cleanup * setup_user_args (char *p);

  48. static char *read_next_line (void);

  50. /* Level of control structure when reading.  */
  51. ‌static int control_level;

  53. /* Level of control structure when executing.  */
  54. ‌static int command_nest_depth = 1;

  56. /* This is to prevent certain commands being printed twice.  */
  57. ‌static int suppress_next_print_command_trace = 0;

  59. /* Structure for arguments to user defined functions.  */
  60. ‌#define MAXUSERARGS 10
  61. ‌struct user_args
  62.   {
  63.     struct user_args *next;
  64.     /* It is necessary to store a malloced copy of the command line to
  65.        ensure that the arguments are not overwritten before they are
  66.        used.  */
  67.     char *command;
  68.     struct
  69.       {
  70.         char *arg;
  71.         int len;
  72.       }
  73.     a[MAXUSERARGS];
  74.     int count;
  75.   }
  76. ‌ *user_args;


  79. /* Return non-zero if TYPE is a multi-line command (i.e., is terminated
  80.    by "end").  */

  82. static int
  83. ‌multi_line_command_p (enum command_control_type type)
  84. {
  85.   switch (type)
  86.     {
  87.     case if_control:
  88.     case while_control:
  89.     case while_stepping_control:
  90.     case commands_control:
  91.     case compile_control:
  92.     case python_control:
  93.     case guile_control:
  94.       return 1;
  95.     default:
  96.       return 0;
  97.     }
  98. }

  100. /* Allocate, initialize a new command line structure for one of the
  101.    control commands (if/while).  */

  103. static struct command_line *
  104. ‌build_command_line (enum command_control_type type, char *args)
  105. {
  106.   struct command_line *cmd;

  108.   if (args == NULL && (type == if_control || type == while_control))
  109.     error (_("if/while commands require arguments."));
  110.   gdb_assert (args != NULL);

  112.   cmd = (struct command_line *) xmalloc (sizeof (struct command_line));
  113.   cmd->next = NULL;
  114.   cmd->control_type = type;

  116.   cmd->body_count = 1;
  117.   cmd->body_list
  118.     = (struct command_line **) xmalloc (sizeof (struct command_line *)
  119.                                         * cmd->body_count);
  120.   memset (cmd->body_list, 0, sizeof (struct command_line *) * cmd->body_count);
  121.   cmd->line = xstrdup (args);

  123.   return cmd;
  124. }

  126. /* Build and return a new command structure for the control commands
  127.    such as "if" and "while".  */

  129. struct command_line *
  130. ‌get_command_line (enum command_control_type type, char *arg)
  131. {
  132.   struct command_line *cmd;
  133.   struct cleanup *old_chain = NULL;

  135.   /* Allocate and build a new command line structure.  */
  136.   cmd = build_command_line (type, arg);

  138.   old_chain = make_cleanup_free_command_lines (&cmd);

  140.   /* Read in the body of this command.  */
  141.   if (recurse_read_control_structure (read_next_line, cmd, 0, 0)
  142.       == invalid_control)
  143.     {
  144.       warning (_("Error reading in canned sequence of commands."));
  145.       do_cleanups (old_chain);
  146.       return NULL;
  147.     }

  149.   discard_cleanups (old_chain);
  150.   return cmd;
  151. }

  153. /* Recursively print a command (including full control structures).  */

  155. void
  156. ‌print_command_lines (struct ui_out *uiout, struct command_line *cmd,
  157.                      unsigned int depth)
  158. {
  159.   struct command_line *list;

  161.   list = cmd;
  162.   while (list)
  163.     {
  164.       if (depth)
  165.         ui_out_spaces (uiout, 2 * depth);

  167.       /* A simple command, print it and continue.  */
  168.       if (list->control_type == simple_control)
  169.         {
  170.           ui_out_field_string (uiout, NULL, list->line);
  171.           ui_out_text (uiout, "\n");
  172.           list = list->next;
  173.           continue;
  174.         }

  176.       /* loop_continue to jump to the start of a while loop, print it
  177.          and continue. */
  178.       if (list->control_type == continue_control)
  179.         {
  180.           ui_out_field_string (uiout, NULL, "loop_continue");
  181.           ui_out_text (uiout, "\n");
  182.           list = list->next;
  183.           continue;
  184.         }

  186.       /* loop_break to break out of a while loop, print it and
  187.          continue.  */
  188.       if (list->control_type == break_control)
  189.         {
  190.           ui_out_field_string (uiout, NULL, "loop_break");
  191.           ui_out_text (uiout, "\n");
  192.           list = list->next;
  193.           continue;
  194.         }

  196.       /* A while command.  Recursively print its subcommands and
  197.          continue.  */
  198.       if (list->control_type == while_control
  199.           || list->control_type == while_stepping_control)
  200.         {
  201.           /* For while-stepping, the line includes the 'while-stepping'
  202.              token.  See comment in process_next_line for explanation.
  203.              Here, take care not print 'while-stepping' twice.  */
  204.           if (list->control_type == while_control)
  205.             ui_out_field_fmt (uiout, NULL, "while %s", list->line);
  206.           else
  207.             ui_out_field_string (uiout, NULL, list->line);
  208.           ui_out_text (uiout, "\n");
  209.           print_command_lines (uiout, *list->body_list, depth + 1);
  210.           if (depth)
  211.             ui_out_spaces (uiout, 2 * depth);
  212.           ui_out_field_string (uiout, NULL, "end");
  213.           ui_out_text (uiout, "\n");
  214.           list = list->next;
  215.           continue;
  216.         }

  218.       /* An if command.  Recursively print both arms before
  219.          continueing.  */
  220.       if (list->control_type == if_control)
  221.         {
  222.           ui_out_field_fmt (uiout, NULL, "if %s", list->line);
  223.           ui_out_text (uiout, "\n");
  224.           /* The true arm.  */
  225.           print_command_lines (uiout, list->body_list[0], depth + 1);

  227.           /* Show the false arm if it exists.  */
  228.           if (list->body_count == 2)
  229.             {
  230.               if (depth)
  231.                 ui_out_spaces (uiout, 2 * depth);
  232.               ui_out_field_string (uiout, NULL, "else");
  233.               ui_out_text (uiout, "\n");
  234.               print_command_lines (uiout, list->body_list[1], depth + 1);
  235.             }

  237.           if (depth)
  238.             ui_out_spaces (uiout, 2 * depth);
  239.           ui_out_field_string (uiout, NULL, "end");
  240.           ui_out_text (uiout, "\n");
  241.           list = list->next;
  242.           continue;
  243.         }

  245.       /* A commands command.  Print the breakpoint commands and
  246.          continue.  */
  247.       if (list->control_type == commands_control)
  248.         {
  249.           if (*(list->line))
  250.             ui_out_field_fmt (uiout, NULL, "commands %s", list->line);
  251.           else
  252.             ui_out_field_string (uiout, NULL, "commands");
  253.           ui_out_text (uiout, "\n");
  254.           print_command_lines (uiout, *list->body_list, depth + 1);
  255.           if (depth)
  256.             ui_out_spaces (uiout, 2 * depth);
  257.           ui_out_field_string (uiout, NULL, "end");
  258.           ui_out_text (uiout, "\n");
  259.           list = list->next;
  260.           continue;
  261.         }

  263.       if (list->control_type == python_control)
  264.         {
  265.           ui_out_field_string (uiout, NULL, "python");
  266.           ui_out_text (uiout, "\n");
  267.           /* Don't indent python code at all.  */
  268.           print_command_lines (uiout, *list->body_list, 0);
  269.           if (depth)
  270.             ui_out_spaces (uiout, 2 * depth);
  271.           ui_out_field_string (uiout, NULL, "end");
  272.           ui_out_text (uiout, "\n");
  273.           list = list->next;
  274.           continue;
  275.         }

  277.       if (list->control_type == compile_control)
  278.         {
  279.           ui_out_field_string (uiout, NULL, "compile expression");
  280.           ui_out_text (uiout, "\n");
  281.           print_command_lines (uiout, *list->body_list, 0);
  282.           if (depth)
  283.             ui_out_spaces (uiout, 2 * depth);
  284.           ui_out_field_string (uiout, NULL, "end");
  285.           ui_out_text (uiout, "\n");
  286.           list = list->next;
  287.           continue;
  288.         }

  290.       if (list->control_type == guile_control)
  291.         {
  292.           ui_out_field_string (uiout, NULL, "guile");
  293.           ui_out_text (uiout, "\n");
  294.           print_command_lines (uiout, *list->body_list, depth + 1);
  295.           if (depth)
  296.             ui_out_spaces (uiout, 2 * depth);
  297.           ui_out_field_string (uiout, NULL, "end");
  298.           ui_out_text (uiout, "\n");
  299.           list = list->next;
  300.           continue;
  301.         }

  303.       /* Ignore illegal command type and try next.  */
  304.       list = list->next;
  305.     }                                /* while (list) */
  306. }

  308. /* Handle pre-post hooks.  */

  310. static void
  311. ‌clear_hook_in_cleanup (void *data)
  312. {
  313.   struct cmd_list_element *c = data;

  315.   c->hook_in = 0; /* Allow hook to work again once it is complete.  */
  316. }

  318. void
  319. ‌execute_cmd_pre_hook (struct cmd_list_element *c)
  320. {
  321.   if ((c->hook_pre) && (!c->hook_in))
  322.     {
  323.       struct cleanup *cleanups = make_cleanup (clear_hook_in_cleanup, c);
  324.       c->hook_in = 1; /* Prevent recursive hooking.  */
  325.       execute_user_command (c->hook_pre, (char *) 0);
  326.       do_cleanups (cleanups);
  327.     }
  328. }

  330. void
  331. ‌execute_cmd_post_hook (struct cmd_list_element *c)
  332. {
  333.   if ((c->hook_post) && (!c->hook_in))
  334.     {
  335.       struct cleanup *cleanups = make_cleanup (clear_hook_in_cleanup, c);

  337.       c->hook_in = 1; /* Prevent recursive hooking.  */
  338.       execute_user_command (c->hook_post, (char *) 0);
  339.       do_cleanups (cleanups);
  340.     }
  341. }

  343. /* Execute the command in CMD.  */
  344. static void
  345. ‌do_restore_user_call_depth (void * call_depth)
  346. {
  347.   int *depth = call_depth;

  349.   (*depth)--;
  350.   if ((*depth) == 0)
  351.     in_user_command = 0;
  352. }


  355. void
  356. ‌execute_user_command (struct cmd_list_element *c, char *args)
  357. {
  358.   struct command_line *cmdlines;
  359.   struct cleanup *old_chain;
  360.   enum command_control_type ret;
  361.   static int user_call_depth = 0;
  362.   extern unsigned int max_user_call_depth;

  364.   cmdlines = c->user_commands;
  365.   if (cmdlines == 0)
  366.     /* Null command */
  367.     return;

  369.   old_chain = setup_user_args (args);

  371.   if (++user_call_depth > max_user_call_depth)
  372.     error (_("Max user call depth exceeded -- command aborted."));

  374.   make_cleanup (do_restore_user_call_depth, &user_call_depth);

  376.   /* Set the instream to 0, indicating execution of a
  377.      user-defined function.  */
  378.   make_cleanup (do_restore_instream_cleanup, instream);
  379.   instream = (FILE *) 0;

  381.   /* Also set the global in_user_command, so that NULL instream is
  382.      not confused with Insight.  */
  383.   in_user_command = 1;

  385.   make_cleanup_restore_integer (&interpreter_async);
  386.   interpreter_async = 0;

  388.   command_nest_depth++;
  389.   while (cmdlines)
  390.     {
  391.       ret = execute_control_command (cmdlines);
  392.       if (ret != simple_control && ret != break_control)
  393.         {
  394.           warning (_("Error executing canned sequence of commands."));
  395.           break;
  396.         }
  397.       cmdlines = cmdlines->next;
  398.     }
  399.   command_nest_depth--;
  400.   do_cleanups (old_chain);
  401. }

  403. /* This function is called every time GDB prints a prompt.  It ensures
  404.    that errors and the like do not confuse the command tracing.  */

  406. void
  407. ‌reset_command_nest_depth (void)
  408. {
  409.   command_nest_depth = 1;

  411.   /* Just in case.  */
  412.   suppress_next_print_command_trace = 0;
  413. }

  415. /* Print the command, prefixed with '+' to represent the call depth.
  416.    This is slightly complicated because this function may be called
  417.    from execute_command and execute_control_command.  Unfortunately
  418.    execute_command also prints the top level control commands.
  419.    In these cases execute_command will call execute_control_command
  420.    via while_command or if_command.  Inner levels of 'if' and 'while'
  421.    are dealt with directly.  Therefore we can use these functions
  422.    to determine whether the command has been printed already or not.  */
  423. void
  424. ‌print_command_trace (const char *cmd)
  425. {
  426.   int i;

  428.   if (suppress_next_print_command_trace)
  429.     {
  430.       suppress_next_print_command_trace = 0;
  431.       return;
  432.     }

  434.   if (!source_verbose && !trace_commands)
  435.     return;

  437.   for (i=0; i < command_nest_depth; i++)
  438.     printf_filtered ("+");

  440.   printf_filtered ("%s\n", cmd);
  441. }

  443. enum command_control_type
  444. ‌execute_control_command (struct command_line *cmd)
  445. {
  446.   struct expression *expr;
  447.   struct command_line *current;
  448.   struct cleanup *old_chain = make_cleanup (null_cleanup, 0);
  449.   struct value *val;
  450.   struct value *val_mark;
  451.   int loop;
  452.   enum command_control_type ret;
  453.   char *new_line;

  455.   /* Start by assuming failure, if a problem is detected, the code
  456.      below will simply "break" out of the switch.  */
  457.   ret = invalid_control;

  459.   switch (cmd->control_type)
  460.     {
  461.     case simple_control:
  462.       /* A simple command, execute it and return.  */
  463.       new_line = insert_args (cmd->line);
  464.       if (!new_line)
  465.         break;
  466.       make_cleanup (free_current_contents, &new_line);
  467.       execute_command (new_line, 0);
  468.       ret = cmd->control_type;
  469.       break;

  471.     case continue_control:
  472.       print_command_trace ("loop_continue");

  474.       /* Return for "continue", and "break" so we can either
  475.          continue the loop at the top, or break out.  */
  476.       ret = cmd->control_type;
  477.       break;

  479.     case break_control:
  480.       print_command_trace ("loop_break");

  482.       /* Return for "continue", and "break" so we can either
  483.          continue the loop at the top, or break out.  */
  484.       ret = cmd->control_type;
  485.       break;

  487.     case while_control:
  488.       {
  489.         int len = strlen (cmd->line) + 7;
  490.         char *buffer = alloca (len);

  492.         xsnprintf (buffer, len, "while %s", cmd->line);
  493.         print_command_trace (buffer);

  495.         /* Parse the loop control expression for the while statement.  */
  496.         new_line = insert_args (cmd->line);
  497.         if (!new_line)
  498.           break;
  499.         make_cleanup (free_current_contents, &new_line);
  500.         expr = parse_expression (new_line);
  501.         make_cleanup (free_current_contents, &expr);

  503.         ret = simple_control;
  504.         loop = 1;

  506.         /* Keep iterating so long as the expression is true.  */
  507.         while (loop == 1)
  508.           {
  509.             int cond_result;

  511.             QUIT;

  513.             /* Evaluate the expression.  */
  514.             val_mark = value_mark ();
  515.             val = evaluate_expression (expr);
  516.             cond_result = value_true (val);
  517.             value_free_to_mark (val_mark);

  519.             /* If the value is false, then break out of the loop.  */
  520.             if (!cond_result)
  521.               break;

  523.             /* Execute the body of the while statement.  */
  524.             current = *cmd->body_list;
  525.             while (current)
  526.               {
  527.                 command_nest_depth++;
  528.                 ret = execute_control_command (current);
  529.                 command_nest_depth--;

  531.                 /* If we got an error, or a "break" command, then stop
  532.                    looping.  */
  533.                 if (ret == invalid_control || ret == break_control)
  534.                   {
  535.                     loop = 0;
  536.                     break;
  537.                   }

  539.                 /* If we got a "continue" command, then restart the loop
  540.                    at this point.  */
  541.                 if (ret == continue_control)
  542.                   break;

  544.                 /* Get the next statement.  */
  545.                 current = current->next;
  546.               }
  547.           }

  549.         /* Reset RET so that we don't recurse the break all the way down.  */
  550.         if (ret == break_control)
  551.           ret = simple_control;

  553.         break;
  554.       }

  556.     case if_control:
  557.       {
  558.         int len = strlen (cmd->line) + 4;
  559.         char *buffer = alloca (len);

  561.         xsnprintf (buffer, len, "if %s", cmd->line);
  562.         print_command_trace (buffer);

  564.         new_line = insert_args (cmd->line);
  565.         if (!new_line)
  566.           break;
  567.         make_cleanup (free_current_contents, &new_line);
  568.         /* Parse the conditional for the if statement.  */
  569.         expr = parse_expression (new_line);
  570.         make_cleanup (free_current_contents, &expr);

  572.         current = NULL;
  573.         ret = simple_control;

  575.         /* Evaluate the conditional.  */
  576.         val_mark = value_mark ();
  577.         val = evaluate_expression (expr);

  579.         /* Choose which arm to take commands from based on the value
  580.            of the conditional expression.  */
  581.         if (value_true (val))
  582.           current = *cmd->body_list;
  583.         else if (cmd->body_count == 2)
  584.           current = *(cmd->body_list + 1);
  585.         value_free_to_mark (val_mark);

  587.         /* Execute commands in the given arm.  */
  588.         while (current)
  589.           {
  590.             command_nest_depth++;
  591.             ret = execute_control_command (current);
  592.             command_nest_depth--;

  594.             /* If we got an error, get out.  */
  595.             if (ret != simple_control)
  596.               break;

  598.             /* Get the next statement in the body.  */
  599.             current = current->next;
  600.           }

  602.         break;
  603.       }

  605.     case commands_control:
  606.       {
  607.         /* Breakpoint commands list, record the commands in the
  608.            breakpoint's command list and return.  */
  609.         new_line = insert_args (cmd->line);
  610.         if (!new_line)
  611.           break;
  612.         make_cleanup (free_current_contents, &new_line);
  613.         ret = commands_from_control_command (new_line, cmd);
  614.         break;
  615.       }

  617.     case compile_control:
  618.       eval_compile_command (cmd, NULL, cmd->control_u.compile.scope);
  619.       ret = simple_control;
  620.       break;

  622.     case python_control:
  623.     case guile_control:
  624.       {
  625.         eval_ext_lang_from_control_command (cmd);
  626.         ret = simple_control;
  627.         break;
  628.       }

  630.     default:
  631.       warning (_("Invalid control type in canned commands structure."));
  632.       break;
  633.     }

  635.   do_cleanups (old_chain);

  637.   return ret;
  638. }

  640. /* Like execute_control_command, but first set
  641.    suppress_next_print_command_trace.  */

  643. enum command_control_type
  644. ‌execute_control_command_untraced (struct command_line *cmd)
  645. {
  646.   suppress_next_print_command_trace = 1;
  647.   return execute_control_command (cmd);
  648. }


  651. /* "while" command support.  Executes a body of statements while the
  652.    loop condition is nonzero.  */

  654. static void
  655. ‌while_command (char *arg, int from_tty)
  656. {
  657.   struct command_line *command = NULL;
  658.   struct cleanup *old_chain;

  660.   control_level = 1;
  661.   command = get_command_line (while_control, arg);

  663.   if (command == NULL)
  664.     return;

  666.   old_chain = make_cleanup_restore_integer (&interpreter_async);
  667.   interpreter_async = 0;

  669.   execute_control_command_untraced (command);
  670.   free_command_lines (&command);

  672.   do_cleanups (old_chain);
  673. }

  675. /* "if" command support.  Execute either the true or false arm depending
  676.    on the value of the if conditional.  */

  678. static void
  679. ‌if_command (char *arg, int from_tty)
  680. {
  681.   struct command_line *command = NULL;
  682.   struct cleanup *old_chain;

  684.   control_level = 1;
  685.   command = get_command_line (if_control, arg);

  687.   if (command == NULL)
  688.     return;

  690.   old_chain = make_cleanup_restore_integer (&interpreter_async);
  691.   interpreter_async = 0;

  693.   execute_control_command_untraced (command);
  694.   free_command_lines (&command);

  696.   do_cleanups (old_chain);
  697. }

  699. /* Cleanup */
  700. static void
  701. ‌arg_cleanup (void *ignore)
  702. {
  703.   struct user_args *oargs = user_args;

  705.   if (!user_args)
  706.     internal_error (__FILE__, __LINE__,
  707.                     _("arg_cleanup called with no user args.\n"));

  709.   user_args = user_args->next;
  710.   xfree (oargs->command);
  711.   xfree (oargs);
  712. }

  714. /* Bind the incomming arguments for a user defined command to
  715.    $arg0, $arg1 ... $argMAXUSERARGS.  */

  717. static struct cleanup *
  718. ‌setup_user_args (char *p)
  719. {
  720.   struct user_args *args;
  721.   struct cleanup *old_chain;
  722.   unsigned int arg_count = 0;

  724.   args = (struct user_args *) xmalloc (sizeof (struct user_args));
  725.   memset (args, 0, sizeof (struct user_args));

  727.   args->next = user_args;
  728.   user_args = args;

  730.   old_chain = make_cleanup (arg_cleanup, 0/*ignored*/);

  732.   if (p == NULL)
  733.     return old_chain;

  735.   user_args->command = p = xstrdup (p);

  737.   while (*p)
  738.     {
  739.       char *start_arg;
  740.       int squote = 0;
  741.       int dquote = 0;
  742.       int bsquote = 0;

  744.       if (arg_count >= MAXUSERARGS)
  745.         error (_("user defined function may only have %d arguments."),
  746.                MAXUSERARGS);

  748.       /* Strip whitespace.  */
  749.       while (*p == ' ' || *p == '\t')
  750.         p++;

  752.       /* P now points to an argument.  */
  753.       start_arg = p;
  754.       user_args->a[arg_count].arg = p;

  756.       /* Get to the end of this argument.  */
  757.       while (*p)
  758.         {
  759.           if (((*p == ' ' || *p == '\t')) && !squote && !dquote && !bsquote)
  760.             break;
  761.           else
  762.             {
  763.               if (bsquote)
  764.                 bsquote = 0;
  765.               else if (*p == '\\')
  766.                 bsquote = 1;
  767.               else if (squote)
  768.                 {
  769.                   if (*p == '\'')
  770.                     squote = 0;
  771.                 }
  772.               else if (dquote)
  773.                 {
  774.                   if (*p == '"')
  775.                     dquote = 0;
  776.                 }
  777.               else
  778.                 {
  779.                   if (*p == '\'')
  780.                     squote = 1;
  781.                   else if (*p == '"')
  782.                     dquote = 1;
  783.                 }
  784.               p++;
  785.             }
  786.         }

  788.       user_args->a[arg_count].len = p - start_arg;
  789.       arg_count++;
  790.       user_args->count++;
  791.     }
  792.   return old_chain;
  793. }

  795. /* Given character string P, return a point to the first argument
  796.    ($arg), or NULL if P contains no arguments.  */

  798. static char *
  799. ‌locate_arg (char *p)
  800. {
  801.   while ((p = strchr (p, '$')))
  802.     {
  803.       if (strncmp (p, "$arg", 4) == 0
  804.           && (isdigit (p[4]) || p[4] == 'c'))
  805.         return p;
  806.       p++;
  807.     }
  808.   return NULL;
  809. }

  811. /* Insert the user defined arguments stored in user_arg into the $arg
  812.    arguments found in line, with the updated copy being placed into
  813.    nline.  */

  815. static char *
  816. ‌insert_args (char *line)
  817. {
  818.   char *p, *save_line, *new_line;
  819.   unsigned len, i;

  821.   /* If we are not in a user-defined function, treat $argc, $arg0, et
  822.      cetera as normal convenience variables.  */
  823.   if (user_args == NULL)
  824.     return xstrdup (line);

  826.   /* First we need to know how much memory to allocate for the new
  827.      line.  */
  828.   save_line = line;
  829.   len = 0;
  830.   while ((p = locate_arg (line)))
  831.     {
  832.       len += p - line;
  833.       i = p[4] - '0';

  835.       if (p[4] == 'c')
  836.         {
  837.           /* $argc.  Number will be <=10.  */
  838.           len += user_args->count == 10 ? 2 : 1;
  839.         }
  840.       else if (i >= user_args->count)
  841.         {
  842.           error (_("Missing argument %d in user function."), i);
  843.           return NULL;
  844.         }
  845.       else
  846.         {
  847.           len += user_args->a[i].len;
  848.         }
  849.       line = p + 5;
  850.     }

  852.   /* Don't forget the tail.  */
  853.   len += strlen (line);

  855.   /* Allocate space for the new line and fill it in.  */
  856.   new_line = (char *) xmalloc (len + 1);
  857.   if (new_line == NULL)
  858.     return NULL;

  860.   /* Restore pointer to beginning of old line.  */
  861.   line = save_line;

  863.   /* Save pointer to beginning of new line.  */
  864.   save_line = new_line;

  866.   while ((p = locate_arg (line)))
  867.     {
  868.       int i, len;

  870.       memcpy (new_line, line, p - line);
  871.       new_line += p - line;

  873.       if (p[4] == 'c')
  874.         {
  875.           gdb_assert (user_args->count >= 0 && user_args->count <= 10);
  876.           if (user_args->count == 10)
  877.             {
  878.               *(new_line++) = '1';
  879.               *(new_line++) = '0';
  880.             }
  881.           else
  882.             *(new_line++) = user_args->count + '0';
  883.         }
  884.       else
  885.         {
  886.           i = p[4] - '0';
  887.           len = user_args->a[i].len;
  888.           if (len)
  889.             {
  890.               memcpy (new_line, user_args->a[i].arg, len);
  891.               new_line += len;
  892.             }
  893.         }
  894.       line = p + 5;
  895.     }
  896.   /* Don't forget the tail.  */
  897.   strcpy (new_line, line);

  899.   /* Return a pointer to the beginning of the new line.  */
  900.   return save_line;
  901. }


  904. /* Expand the body_list of COMMAND so that it can hold NEW_LENGTH
  905.    code bodies.  This is typically used when we encounter an "else"
  906.    clause for an "if" command.  */

  908. static void
  909. ‌realloc_body_list (struct command_line *command, int new_length)
  910. {
  911.   int n;
  912.   struct command_line **body_list;

  914.   n = command->body_count;

  916.   /* Nothing to do?  */
  917.   if (new_length <= n)
  918.     return;

  920.   body_list = (struct command_line **)
  921.     xmalloc (sizeof (struct command_line *) * new_length);

  923.   memcpy (body_list, command->body_list, sizeof (struct command_line *) * n);
  924.   memset (body_list + n, 0, sizeof (struct command_line *) * (new_length - n));

  926.   xfree (command->body_list);
  927.   command->body_list = body_list;
  928.   command->body_count = new_length;
  929. }

  931. /* Read next line from stdout.  Passed to read_command_line_1 and
  932.    recurse_read_control_structure whenever we need to read commands
  933.    from stdout.  */

  935. static char *
  936. ‌read_next_line (void)
  937. {
  938.   char *prompt_ptr, control_prompt[256];
  939.   int i = 0;

  941.   if (control_level >= 254)
  942.     error (_("Control nesting too deep!"));

  944.   /* Set a prompt based on the nesting of the control commands.  */
  945.   if (instream == stdin || (instream == 0 && deprecated_readline_hook != NULL))
  946.     {
  947.       for (i = 0; i < control_level; i++)
  948.         control_prompt[i] = ' ';
  949.       control_prompt[i] = '>';
  950.       control_prompt[i + 1] = '\0';
  951.       prompt_ptr = (char *) &control_prompt[0];
  952.     }
  953.   else
  954.     prompt_ptr = NULL;

  956.   return command_line_input (prompt_ptr, instream == stdin, "commands");
  957. }

  959. /* Process one input line.  If the command is an "end", return such an
  960.    indication to the caller.  If PARSE_COMMANDS is true, strip leading
  961.    whitespace (trailing whitespace is always stripped) in the line,
  962.    attempt to recognize GDB control commands, and also return an
  963.    indication if the command is an "else" or a nop.

  965.    Otherwise, only "end" is recognized.  */

  967. static enum misc_command_type
  968. ‌process_next_line (char *p, struct command_line **command, int parse_commands,
  969.                    void (*validator)(char *, void *), void *closure)
  970. {
  971.   char *p_end;
  972.   char *p_start;
  973.   int not_handled = 0;

  975.   /* Not sure what to do here.  */
  976.   if (p == NULL)
  977.     return end_command;

  979.   /* Strip trailing whitespace.  */
  980.   p_end = p + strlen (p);
  981.   while (p_end > p && (p_end[-1] == ' ' || p_end[-1] == '\t'))
  982.     p_end--;

  984.   p_start = p;
  985.   /* Strip leading whitespace.  */
  986.   while (p_start < p_end && (*p_start == ' ' || *p_start == '\t'))
  987.     p_start++;

  989.   /* 'end' is always recognized, regardless of parse_commands value.
  990.      We also permit whitespace before end and after.  */
  991.   if (p_end - p_start == 3 && !strncmp (p_start, "end", 3))
  992.     return end_command;

  994.   if (parse_commands)
  995.     {
  996.       /* If commands are parsed, we skip initial spaces.  Otherwise,
  997.          which is the case for Python commands and documentation
  998.          (see the 'document' command), spaces are preserved.  */
  999.       p = p_start;

  1001.       /* Blanks and comments don't really do anything, but we need to
  1002.          distinguish them from else, end and other commands which can
  1003.          be executed.  */
  1004.       if (p_end == p || p[0] == '#')
  1005.         return nop_command;

  1007.       /* Is the else clause of an if control structure?  */
  1008.       if (p_end - p == 4 && !strncmp (p, "else", 4))
  1009.         return else_command;

  1011.       /* Check for while, if, break, continue, etc and build a new
  1012.          command line structure for them.  */
  1013.       if ((p_end - p >= 14 && !strncmp (p, "while-stepping", 14))
  1014.           || (p_end - p >= 8 && !strncmp (p, "stepping", 8))
  1015.           || (p_end - p >= 2 && !strncmp (p, "ws", 2)))
  1016.         {
  1017.           /* Because validate_actionline and encode_action lookup
  1018.              command's line as command, we need the line to
  1019.              include 'while-stepping'.

  1021.              For 'ws' alias, the command will have 'ws', not expanded
  1022.              to 'while-stepping'.  This is intentional -- we don't
  1023.              really want frontend to send a command list with 'ws',
  1024.              and next break-info returning command line with
  1025.              'while-stepping'.  This should work, but might cause the
  1026.              breakpoint to be marked as changed while it's actually
  1027.              not.  */
  1028.           *command = build_command_line (while_stepping_control, p);
  1029.         }
  1030.       else if (p_end - p > 5 && !strncmp (p, "while", 5))
  1031.         {
  1032.           char *first_arg;

  1034.           first_arg = p + 5;
  1035.           while (first_arg < p_end && isspace (*first_arg))
  1036.             first_arg++;
  1037.           *command = build_command_line (while_control, first_arg);
  1038.         }
  1039.       else if (p_end - p > 2 && !strncmp (p, "if", 2))
  1040.         {
  1041.           char *first_arg;

  1043.           first_arg = p + 2;
  1044.           while (first_arg < p_end && isspace (*first_arg))
  1045.             first_arg++;
  1046.           *command = build_command_line (if_control, first_arg);
  1047.         }
  1048.       else if (p_end - p >= 8 && !strncmp (p, "commands", 8))
  1049.         {
  1050.           char *first_arg;

  1052.           first_arg = p + 8;
  1053.           while (first_arg < p_end && isspace (*first_arg))
  1054.             first_arg++;
  1055.           *command = build_command_line (commands_control, first_arg);
  1056.         }
  1057.       else if (p_end - p == 6 && !strncmp (p, "python", 6))
  1058.         {
  1059.           /* Note that we ignore the inline "python command" form
  1060.              here.  */
  1061.           *command = build_command_line (python_control, "");
  1062.         }
  1063.       else if (p_end - p == 6 && !strncmp (p, "compile", 7))
  1064.         {
  1065.           /* Note that we ignore the inline "compile command" form
  1066.              here.  */
  1067.           *command = build_command_line (compile_control, "");
  1068.           (*command)->control_u.compile.scope = COMPILE_I_INVALID_SCOPE;
  1069.         }

  1071.       else if (p_end - p == 5 && !strncmp (p, "guile", 5))
  1072.         {
  1073.           /* Note that we ignore the inline "guile command" form here.  */
  1074.           *command = build_command_line (guile_control, "");
  1075.         }
  1076.       else if (p_end - p == 10 && !strncmp (p, "loop_break", 10))
  1077.         {
  1078.           *command = (struct command_line *)
  1079.             xmalloc (sizeof (struct command_line));
  1080.           (*command)->next = NULL;
  1081.           (*command)->line = NULL;
  1082.           (*command)->control_type = break_control;
  1083.           (*command)->body_count = 0;
  1084.           (*command)->body_list = NULL;
  1085.         }
  1086.       else if (p_end - p == 13 && !strncmp (p, "loop_continue", 13))
  1087.         {
  1088.           *command = (struct command_line *)
  1089.             xmalloc (sizeof (struct command_line));
  1090.           (*command)->next = NULL;
  1091.           (*command)->line = NULL;
  1092.           (*command)->control_type = continue_control;
  1093.           (*command)->body_count = 0;
  1094.           (*command)->body_list = NULL;
  1095.         }
  1096.       else
  1097.         not_handled = 1;
  1098.     }

  1100.   if (!parse_commands || not_handled)
  1101.     {
  1102.       /* A normal command.  */
  1103.       *command = (struct command_line *)
  1104.         xmalloc (sizeof (struct command_line));
  1105.       (*command)->next = NULL;
  1106.       (*command)->line = savestring (p, p_end - p);
  1107.       (*command)->control_type = simple_control;
  1108.       (*command)->body_count = 0;
  1109.       (*command)->body_list = NULL;
  1110.     }

  1112.   if (validator)
  1113.     {
  1114.       volatile struct gdb_exception ex;

  1116.       TRY_CATCH (ex, RETURN_MASK_ALL)
  1117.         {
  1118.           validator ((*command)->line, closure);
  1119.         }
  1120.       if (ex.reason < 0)
  1121.         {
  1122.           xfree (*command);
  1123.           throw_exception (ex);
  1124.         }
  1125.     }

  1127.   /* Nothing special.  */
  1128.   return ok_command;
  1129. }

  1131. /* Recursively read in the control structures and create a
  1132.    command_line structure from them.  Use read_next_line_func to
  1133.    obtain lines of the command.  */

  1135. static enum command_control_type
  1136. ‌recurse_read_control_structure (char * (*read_next_line_func) (void),
  1137.                                 struct command_line *current_cmd,
  1138.                                 void (*validator)(char *, void *),
  1139.                                 void *closure)
  1140. {
  1141.   int current_body, i;
  1142.   enum misc_command_type val;
  1143.   enum command_control_type ret;
  1144.   struct command_line **body_ptr, *child_tail, *next;

  1146.   child_tail = NULL;
  1147.   current_body = 1;

  1149.   /* Sanity checks.  */
  1150.   if (current_cmd->control_type == simple_control)
  1151.     error (_("Recursed on a simple control type."));

  1153.   if (current_body > current_cmd->body_count)
  1154.     error (_("Allocated body is smaller than this command type needs."));

  1156.   /* Read lines from the input stream and build control structures.  */
  1157.   while (1)
  1158.     {
  1159.       dont_repeat ();

  1161.       next = NULL;
  1162.       val = process_next_line (read_next_line_func (), &next,
  1163.                                current_cmd->control_type != python_control
  1164.                                && current_cmd->control_type != guile_control
  1165.                                && current_cmd->control_type != compile_control,
  1166.                                validator, closure);

  1168.       /* Just skip blanks and comments.  */
  1169.       if (val == nop_command)
  1170.         continue;

  1172.       if (val == end_command)
  1173.         {
  1174.           if (multi_line_command_p (current_cmd->control_type))
  1175.             {
  1176.               /* Success reading an entire canned sequence of commands.  */
  1177.               ret = simple_control;
  1178.               break;
  1179.             }
  1180.           else
  1181.             {
  1182.               ret = invalid_control;
  1183.               break;
  1184.             }
  1185.         }

  1187.       /* Not the end of a control structure.  */
  1188.       if (val == else_command)
  1189.         {
  1190.           if (current_cmd->control_type == if_control
  1191.               && current_body == 1)
  1192.             {
  1193.               realloc_body_list (current_cmd, 2);
  1194.               current_body = 2;
  1195.               child_tail = NULL;
  1196.               continue;
  1197.             }
  1198.           else
  1199.             {
  1200.               ret = invalid_control;
  1201.               break;
  1202.             }
  1203.         }

  1205.       if (child_tail)
  1206.         {
  1207.           child_tail->next = next;
  1208.         }
  1209.       else
  1210.         {
  1211.           body_ptr = current_cmd->body_list;
  1212.           for (i = 1; i < current_body; i++)
  1213.             body_ptr++;

  1215.           *body_ptr = next;

  1217.         }

  1219.       child_tail = next;

  1221.       /* If the latest line is another control structure, then recurse
  1222.          on it.  */
  1223.       if (multi_line_command_p (next->control_type))
  1224.         {
  1225.           control_level++;
  1226.           ret = recurse_read_control_structure (read_next_line_func, next,
  1227.                                                 validator, closure);
  1228.           control_level--;

  1230.           if (ret != simple_control)
  1231.             break;
  1232.         }
  1233.     }

  1235.   dont_repeat ();

  1237.   return ret;
  1238. }

  1240. static void
  1241. ‌restore_interp (void *arg)
  1242. {
  1243.   interp_set_temp (interp_name ((struct interp *)arg));
  1244. }

  1246. /* Read lines from the input stream and accumulate them in a chain of
  1247.    struct command_line's, which is then returned.  For input from a
  1248.    terminal, the special command "end" is used to mark the end of the
  1249.    input, and is not included in the returned chain of commands.

  1251.    If PARSE_COMMANDS is true, strip leading whitespace (trailing whitespace
  1252.    is always stripped) in the line and attempt to recognize GDB control
  1253.    commands.  Otherwise, only "end" is recognized.  */

  1255. ‌#define END_MESSAGE "End with a line saying just \"end\"."

  1257. struct command_line *
  1258. ‌read_command_lines (char *prompt_arg, int from_tty, int parse_commands,
  1259.                     void (*validator)(char *, void *), void *closure)
  1260. {
  1261.   struct command_line *head;

  1263.   if (from_tty && input_from_terminal_p ())
  1264.     {
  1265.       if (deprecated_readline_begin_hook)
  1266.         {
  1267.           /* Note - intentional to merge messages with no newline.  */
  1268.           (*deprecated_readline_begin_hook) ("%s  %s\n", prompt_arg,
  1269.                                              END_MESSAGE);
  1270.         }
  1271.       else
  1272.         {
  1273.           printf_unfiltered ("%s\n%s\n", prompt_arg, END_MESSAGE);
  1274.           gdb_flush (gdb_stdout);
  1275.         }
  1276.     }


  1279.   /* Reading commands assumes the CLI behavior, so temporarily
  1280.      override the current interpreter with CLI.  */
  1281.   if (current_interp_named_p (INTERP_CONSOLE))
  1282.     head = read_command_lines_1 (read_next_line, parse_commands,
  1283.                                  validator, closure);
  1284.   else
  1285.     {
  1286.       struct interp *old_interp = interp_set_temp (INTERP_CONSOLE);
  1287.       struct cleanup *old_chain = make_cleanup (restore_interp, old_interp);

  1289.       head = read_command_lines_1 (read_next_line, parse_commands,
  1290.                                    validator, closure);
  1291.       do_cleanups (old_chain);
  1292.     }

  1294.   if (deprecated_readline_end_hook && from_tty && input_from_terminal_p ())
  1295.     {
  1296.       (*deprecated_readline_end_hook) ();
  1297.     }
  1298.   return (head);
  1299. }

  1301. /* Act the same way as read_command_lines, except that each new line is
  1302.    obtained using READ_NEXT_LINE_FUNC.  */

  1304. struct command_line *
  1305. ‌read_command_lines_1 (char * (*read_next_line_func) (void), int parse_commands,
  1306.                       void (*validator)(char *, void *), void *closure)
  1307. {
  1308.   struct command_line *head, *tail, *next;
  1309.   struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
  1310.   enum command_control_type ret;
  1311.   enum misc_command_type val;

  1313.   control_level = 0;
  1314.   head = tail = NULL;

  1316.   while (1)
  1317.     {
  1318.       dont_repeat ();
  1319.       val = process_next_line (read_next_line_func (), &next, parse_commands,
  1320.                                validator, closure);

  1322.       /* Ignore blank lines or comments.  */
  1323.       if (val == nop_command)
  1324.         continue;

  1326.       if (val == end_command)
  1327.         {
  1328.           ret = simple_control;
  1329.           break;
  1330.         }

  1332.       if (val != ok_command)
  1333.         {
  1334.           ret = invalid_control;
  1335.           break;
  1336.         }

  1338.       if (multi_line_command_p (next->control_type))
  1339.         {
  1340.           control_level++;
  1341.           ret = recurse_read_control_structure (read_next_line_func, next,
  1342.                                                 validator, closure);
  1343.           control_level--;

  1345.           if (ret == invalid_control)
  1346.             break;
  1347.         }

  1349.       if (tail)
  1350.         {
  1351.           tail->next = next;
  1352.         }
  1353.       else
  1354.         {
  1355.           head = next;
  1356.           make_cleanup_free_command_lines (&head);
  1357.         }
  1358.       tail = next;
  1359.     }

  1361.   dont_repeat ();

  1363.   if (ret != invalid_control)
  1364.     discard_cleanups (old_chain);
  1365.   else
  1366.     do_cleanups (old_chain);

  1368.   return head;
  1369. }

  1371. /* Free a chain of struct command_line's.  */

  1373. void
  1374. ‌free_command_lines (struct command_line **lptr)
  1375. {
  1376.   struct command_line *l = *lptr;
  1377.   struct command_line *next;
  1378.   struct command_line **blist;
  1379.   int i;

  1381.   while (l)
  1382.     {
  1383.       if (l->body_count > 0)
  1384.         {
  1385.           blist = l->body_list;
  1386.           for (i = 0; i < l->body_count; i++, blist++)
  1387.             free_command_lines (blist);
  1388.         }
  1389.       next = l->next;
  1390.       xfree (l->line);
  1391.       xfree (l);
  1392.       l = next;
  1393.     }
  1394.   *lptr = NULL;
  1395. }

  1397. static void
  1398. ‌do_free_command_lines_cleanup (void *arg)
  1399. {
  1400.   free_command_lines (arg);
  1401. }

  1403. struct cleanup *
  1404. ‌make_cleanup_free_command_lines (struct command_line **arg)
  1405. {
  1406.   return make_cleanup (do_free_command_lines_cleanup, arg);
  1407. }

  1409. struct command_line *
  1410. ‌copy_command_lines (struct command_line *cmds)
  1411. {
  1412.   struct command_line *result = NULL;

  1414.   if (cmds)
  1415.     {
  1416.       result = (struct command_line *) xmalloc (sizeof (struct command_line));

  1418.       result->next = copy_command_lines (cmds->next);
  1419.       result->line = xstrdup (cmds->line);
  1420.       result->control_type = cmds->control_type;
  1421.       result->body_count = cmds->body_count;
  1422.       if (cmds->body_count > 0)
  1423.         {
  1424.           int i;

  1426.           result->body_list = (struct command_line **)
  1427.             xmalloc (sizeof (struct command_line *) * cmds->body_count);

  1429.           for (i = 0; i < cmds->body_count; i++)
  1430.             result->body_list[i] = copy_command_lines (cmds->body_list[i]);
  1431.         }
  1432.       else
  1433.         result->body_list = NULL;
  1434.     }

  1436.   return result;
  1437. }

  1439. /* Validate that *COMNAME is a valid name for a command.  Return the
  1440.    containing command list, in case it starts with a prefix command.
  1441.    The prefix must already exist.  *COMNAME is advanced to point after
  1442.    any prefix, and a NUL character overwrites the space after the
  1443.    prefix.  */

  1445. static struct cmd_list_element **
  1446. ‌validate_comname (char **comname)
  1447. {
  1448.   struct cmd_list_element **list = &cmdlist;
  1449.   char *p, *last_word;

  1451.   if (*comname == 0)
  1452.     error_no_arg (_("name of command to define"));

  1454.   /* Find the last word of the argument.  */
  1455.   p = *comname + strlen (*comname);
  1456.   while (p > *comname && isspace (p[-1]))
  1457.     p--;
  1458.   while (p > *comname && !isspace (p[-1]))
  1459.     p--;
  1460.   last_word = p;

  1462.   /* Find the corresponding command list.  */
  1463.   if (last_word != *comname)
  1464.     {
  1465.       struct cmd_list_element *c;
  1466.       char saved_char;
  1467.       const char *tem = *comname;

  1469.       /* Separate the prefix and the command.  */
  1470.       saved_char = last_word[-1];
  1471.       last_word[-1] = '\0';

  1473.       c = lookup_cmd (&tem, cmdlist, "", 0, 1);
  1474.       if (c->prefixlist == NULL)
  1475.         error (_("\"%s\" is not a prefix command."), *comname);

  1477.       list = c->prefixlist;
  1478.       last_word[-1] = saved_char;
  1479.       *comname = last_word;
  1480.     }

  1482.   p = *comname;
  1483.   while (*p)
  1484.     {
  1485.       if (!isalnum (*p) && *p != '-' && *p != '_')
  1486.         error (_("Junk in argument list: \"%s\""), p);
  1487.       p++;
  1488.     }

  1490.   return list;
  1491. }

  1493. /* This is just a placeholder in the command data structures.  */
  1494. static void
  1495. ‌user_defined_command (char *ignore, int from_tty)
  1496. {
  1497. }

  1499. static void
  1500. ‌define_command (char *comname, int from_tty)
  1501. {
  1502. ‌#define MAX_TMPBUF 128
  1503.   enum cmd_hook_type
  1504.     {
  1505.       CMD_NO_HOOK = 0,
  1506.       CMD_PRE_HOOK,
  1507.       CMD_POST_HOOK
  1508.     };
  1509.   struct command_line *cmds;
  1510.   struct cmd_list_element *c, *newc, *hookc = 0, **list;
  1511.   char *tem, *comfull;
  1512.   const char *tem_c;
  1513.   char tmpbuf[MAX_TMPBUF];
  1514.   int  hook_type      = CMD_NO_HOOK;
  1515.   int  hook_name_size = 0;

  1517. ‌#define        HOOK_STRING        "hook-"
  1518. ‌#define        HOOK_LEN 5
  1519. ‌#define HOOK_POST_STRING "hookpost-"
  1520. ‌#define HOOK_POST_LEN    9

  1522.   comfull = comname;
  1523.   list = validate_comname (&comname);

  1525.   /* Look it up, and verify that we got an exact match.  */
  1526.   tem_c = comname;
  1527.   c = lookup_cmd (&tem_c, *list, "", -1, 1);
  1528.   if (c && strcmp (comname, c->name) != 0)
  1529.     c = 0;

  1531.   if (c)
  1532.     {
  1533.       int q;

  1535.       if (c->class == class_user || c->class == class_alias)
  1536.         q = query (_("Redefine command \"%s\"? "), c->name);
  1537.       else
  1538.         q = query (_("Really redefine built-in command \"%s\"? "), c->name);
  1539.       if (!q)
  1540.         error (_("Command \"%s\" not redefined."), c->name);
  1541.     }

  1543.   /* If this new command is a hook, then mark the command which it
  1544.      is hooking.  Note that we allow hooking `help' commands, so that
  1545.      we can hook the `stop' pseudo-command.  */

  1547.   if (!strncmp (comname, HOOK_STRING, HOOK_LEN))
  1548.     {
  1549.        hook_type      = CMD_PRE_HOOK;
  1550.        hook_name_size = HOOK_LEN;
  1551.     }
  1552.   else if (!strncmp (comname, HOOK_POST_STRING, HOOK_POST_LEN))
  1553.     {
  1554.       hook_type      = CMD_POST_HOOK;
  1555.       hook_name_size = HOOK_POST_LEN;
  1556.     }

  1558.   if (hook_type != CMD_NO_HOOK)
  1559.     {
  1560.       /* Look up cmd it hooks, and verify that we got an exact match.  */
  1561.       tem_c = comname + hook_name_size;
  1562.       hookc = lookup_cmd (&tem_c, *list, "", -1, 0);
  1563.       if (hookc && strcmp (comname + hook_name_size, hookc->name) != 0)
  1564.         hookc = 0;
  1565.       if (!hookc)
  1566.         {
  1567.           warning (_("Your new `%s' command does not "
  1568.                      "hook any existing command."),
  1569.                    comfull);
  1570.           if (!query (_("Proceed? ")))
  1571.             error (_("Not confirmed."));
  1572.         }
  1573.     }

  1575.   comname = xstrdup (comname);

  1577.   /* If the rest of the commands will be case insensitive, this one
  1578.      should behave in the same manner.  */
  1579.   for (tem = comname; *tem; tem++)
  1580.     if (isupper (*tem))
  1581.       *tem = tolower (*tem);

  1583.   xsnprintf (tmpbuf, sizeof (tmpbuf),
  1584.              "Type commands for definition of \"%s\".", comfull);
  1585.   cmds = read_command_lines (tmpbuf, from_tty, 1, 0, 0);

  1587.   if (c && c->class == class_user)
  1588.     free_command_lines (&c->user_commands);

  1590.   newc = add_cmd (comname, class_user, user_defined_command,
  1591.                   (c && c->class == class_user)
  1592.                   ? c->doc : xstrdup ("User-defined."), list);
  1593.   newc->user_commands = cmds;

  1595.   /* If this new command is a hook, then mark both commands as being
  1596.      tied.  */
  1597.   if (hookc)
  1598.     {
  1599.       switch (hook_type)
  1600.         {
  1601.         case CMD_PRE_HOOK:
  1602.           hookc->hook_pre  = newc;  /* Target gets hooked.  */
  1603.           newc->hookee_pre = hookc; /* We are marked as hooking target cmd.  */
  1604.           break;
  1605.         case CMD_POST_HOOK:
  1606.           hookc->hook_post  = newc;  /* Target gets hooked.  */
  1607.           newc->hookee_post = hookc; /* We are marked as hooking
  1608.                                         target cmd.  */
  1609.           break;
  1610.         default:
  1611.           /* Should never come here as hookc would be 0.  */
  1612.           internal_error (__FILE__, __LINE__, _("bad switch"));
  1613.         }
  1614.     }
  1615. }

  1617. static void
  1618. ‌document_command (char *comname, int from_tty)
  1619. {
  1620.   struct command_line *doclines;
  1621.   struct cmd_list_element *c, **list;
  1622.   const char *tem;
  1623.   char *comfull;
  1624.   char tmpbuf[128];

  1626.   comfull = comname;
  1627.   list = validate_comname (&comname);

  1629.   tem = comname;
  1630.   c = lookup_cmd (&tem, *list, "", 0, 1);

  1632.   if (c->class != class_user)
  1633.     error (_("Command \"%s\" is built-in."), comfull);

  1635.   xsnprintf (tmpbuf, sizeof (tmpbuf), "Type documentation for \"%s\".",
  1636.              comfull);
  1637.   doclines = read_command_lines (tmpbuf, from_tty, 0, 0, 0);

  1639.   if (c->doc)
  1640.     xfree ((char *) c->doc);

  1642.   {
  1643.     struct command_line *cl1;
  1644.     int len = 0;
  1645.     char *doc;

  1647.     for (cl1 = doclines; cl1; cl1 = cl1->next)
  1648.       len += strlen (cl1->line) + 1;

  1650.     doc = (char *) xmalloc (len + 1);
  1651.     *doc = 0;

  1653.     for (cl1 = doclines; cl1; cl1 = cl1->next)
  1654.       {
  1655.         strcat (doc, cl1->line);
  1656.         if (cl1->next)
  1657.           strcat (doc, "\n");
  1658.       }

  1660.     c->doc = doc;
  1661.   }

  1663.   free_command_lines (&doclines);
  1664. }

  1666. ‌struct source_cleanup_lines_args
  1667. {
  1668.   int old_line;
  1669.   const char *old_file;
  1670. };

  1672. static void
  1673. ‌source_cleanup_lines (void *args)
  1674. {
  1675.   struct source_cleanup_lines_args *p =
  1676.     (struct source_cleanup_lines_args *) args;

  1678.   source_line_number = p->old_line;
  1679.   source_file_name = p->old_file;
  1680. }

  1682. /* Used to implement source_command.  */

  1684. void
  1685. ‌script_from_file (FILE *stream, const char *file)
  1686. {
  1687.   struct cleanup *old_cleanups;
  1688.   struct source_cleanup_lines_args old_lines;

  1690.   if (stream == NULL)
  1691.     internal_error (__FILE__, __LINE__, _("called with NULL file pointer!"));

  1693.   old_lines.old_line = source_line_number;
  1694.   old_lines.old_file = source_file_name;
  1695.   old_cleanups = make_cleanup (source_cleanup_lines, &old_lines);
  1696.   source_line_number = 0;
  1697.   source_file_name = file;

  1699.   make_cleanup_restore_integer (&interpreter_async);
  1700.   interpreter_async = 0;

  1702.   {
  1703.     volatile struct gdb_exception e;

  1705.     TRY_CATCH (e, RETURN_MASK_ERROR)
  1706.       {
  1707.         read_command_file (stream);
  1708.       }
  1709.     switch (e.reason)
  1710.       {
  1711.       case 0:
  1712.         break;
  1713.       case RETURN_ERROR:
  1714.         /* Re-throw the error, but with the file name information
  1715.            prepended.  */
  1716.         throw_error (e.error,
  1717.                      _("%s:%d: Error in sourced command file:\n%s"),
  1718.                      source_file_name, source_line_number, e.message);
  1719.       default:
  1720.         internal_error (__FILE__, __LINE__, _("bad reason"));
  1721.       }
  1722.   }

  1724.   do_cleanups (old_cleanups);
  1725. }

  1727. /* Print the definition of user command C to STREAM.  Or, if C is a
  1728.    prefix command, show the definitions of all user commands under C
  1729.    (recursively).  PREFIX and NAME combined are the name of the
  1730.    current command.  */
  1731. void
  1732. ‌show_user_1 (struct cmd_list_element *c, const char *prefix, const char *name,
  1733.              struct ui_file *stream)
  1734. {
  1735.   struct command_line *cmdlines;

  1737.   if (c->prefixlist != NULL)
  1738.     {
  1739.       const char *prefixname = c->prefixname;

  1741.       for (c = *c->prefixlist; c != NULL; c = c->next)
  1742.         if (c->class == class_user || c->prefixlist != NULL)
  1743.           show_user_1 (c, prefixname, c->name, gdb_stdout);
  1744.       return;
  1745.     }

  1747.   cmdlines = c->user_commands;
  1748.   fprintf_filtered (stream, "User command \"%s%s\":\n", prefix, name);

  1750.   if (!cmdlines)
  1751.     return;
  1752.   print_command_lines (current_uiout, cmdlines, 1);
  1753.   fputs_filtered ("\n", stream);
  1754. }



  1758. ‌initialize_file_ftype _initialize_cli_script;

  1760. void
  1761. ‌_initialize_cli_script (void)
  1762. {
  1763.   add_com ("document", class_support, document_command, _("\
  1764. Document a user-defined command.\n\
  1765. Give command name as argument.  Give documentation on following lines.\n\
  1766. End with a line of just \"end\"."));
  1767.   add_com ("define", class_support, define_command, _("\
  1768. Define a new command name.  Command name is argument.\n\
  1769. Definition appears on following lines, one command per line.\n\
  1770. End with a line of just \"end\".\n\
  1771. Use the \"document\" command to give documentation for the new command.\n\
  1772. Commands defined in this way may have up to ten arguments."));

  1774.   add_com ("while", class_support, while_command, _("\
  1775. Execute nested commands WHILE the conditional expression is non zero.\n\
  1776. The conditional expression must follow the word `while' and must in turn be\n\
  1777. followed by a new line.  The nested commands must be entered one per line,\n\
  1778. and should be terminated by the word `end'."));

  1780.   add_com ("if", class_support, if_command, _("\
  1781. Execute nested commands once IF the conditional expression is non zero.\n\
  1782. The conditional expression must follow the word `if' and must in turn be\n\
  1783. followed by a new line.  The nested commands must be entered one per line,\n\
  1784. and should be terminated by the word 'else' or `end'.  If an else clause\n\
  1785. is used, the same rules apply to its nested commands as to the first ones."));
  1786. }