From 01770bbde902e075e524b518ac6c1087a4cc1cfb Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Fri, 2 Dec 2016 19:17:13 +0000 Subject: [PATCH] Fix PR 20559 - "eval" command and $arg0...$arg9/$argc substitution It'd be handy to be able to iterate over command arguments in user-defined commands, in order to support optional arguments ($arg0..$argN). I thought I could make it work with "eval", but alas, it doesn't work currently. E.g., with: define test set $i = 0 while $i < $argc eval "print $arg%d", $i set $i = $i + 1 end end we get: (gdb) test 1 $1 = void (gdb) test 1 2 3 $2 = void $3 = void $4 = void (gdb) The problem is that "eval" doesn't do user-defined command arguments substitution after expanding its own argument. This patch fixes that, which makes the example above work: (gdb) test 1 $1 = 1 (gdb) test 1 2 3 $2 = 1 $3 = 2 $4 = 3 (gdb) New test included, similar the above, but also exercises expanding $argc. I think this is likely to simplify many scripts out there, so I'm adding an example to the manual and mentioning it in NEWS as well. gdb/ChangeLog: 2016-12-02 Pedro Alves PR cli/20559 * NEWS: Mention "eval" expands user-defined command arguments. * cli/cli-script.c (execute_control_command): Adjust to rename. (insert_args): Rename to ... (insert_user_defined_cmd_args): ... this, and make extern. * cli/cli-script.h (insert_user_defined_cmd_args): New declaration. * printcmd.c: Include "cli/cli-script.h". (eval_command): Call insert_user_defined_cmd_args. gdb/doc/ChangeLog: 2016-12-02 Pedro Alves PR cli/20559 * gdb.texinfo (Define): Add example of using "eval" to process a variable number of arguments. (Output) : Add anchor. gdb/testsuite/ChangeLog: 2016-12-02 Pedro Alves PR cli/20559 * gdb.base/commands.exp (user_defined_command_args_eval): New procedure. (top level): Call it. --- gdb/ChangeLog | 12 +++++++++++ gdb/NEWS | 12 +++++++++++ gdb/cli/cli-script.c | 19 ++++++++---------- gdb/cli/cli-script.h | 6 ++++++ gdb/doc/ChangeLog | 7 +++++++ gdb/doc/gdb.texinfo | 16 +++++++++++++++ gdb/printcmd.c | 3 +++ gdb/testsuite/ChangeLog | 7 +++++++ gdb/testsuite/gdb.base/commands.exp | 31 +++++++++++++++++++++++++++++ 9 files changed, 102 insertions(+), 11 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 33d824304f3..2066268be1a 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,15 @@ +2016-12-02 Pedro Alves + + PR cli/20559 + * NEWS: Mention "eval" expands user-defined command arguments. + * cli/cli-script.c (execute_control_command): Adjust to rename. + (insert_args): Rename to ... + (insert_user_defined_cmd_args): ... this, and make extern. + * cli/cli-script.h (insert_user_defined_cmd_args): New + declaration. + * printcmd.c: Include "cli/cli-script.h". + (eval_command): Call insert_user_defined_cmd_args. + 2016-12-02 Tom Tromey PR symtab/16264: diff --git a/gdb/NEWS b/gdb/NEWS index a5974053e45..408912443e5 100644 --- a/gdb/NEWS +++ b/gdb/NEWS @@ -32,6 +32,18 @@ * Support for Java programs compiled with gcj has been removed. +* The "eval" command now expands user-defined command arguments. + + This makes it easier to process a variable number of arguments: + + define mycommand + set $i = 0 + while $i < $argc + eval "print $arg%d", $i + set $i = $i + 1 + end + end + * New targets Synopsys ARC arc*-*-elf32 diff --git a/gdb/cli/cli-script.c b/gdb/cli/cli-script.c index ce4d8cb103b..15947a9a78a 100644 --- a/gdb/cli/cli-script.c +++ b/gdb/cli/cli-script.c @@ -41,8 +41,6 @@ recurse_read_control_structure (char * (*read_next_line_func) (void), void (*validator)(char *, void *), void *closure); -static std::string insert_args (const char *line); - static struct cleanup * setup_user_args (char *p); static char *read_next_line (void); @@ -455,7 +453,7 @@ execute_control_command (struct command_line *cmd) case simple_control: { /* A simple command, execute it and return. */ - std::string new_line = insert_args (cmd->line); + std::string new_line = insert_user_defined_cmd_args (cmd->line); execute_command (&new_line[0], 0); ret = cmd->control_type; break; @@ -486,7 +484,7 @@ execute_control_command (struct command_line *cmd) print_command_trace (buffer); /* Parse the loop control expression for the while statement. */ - std::string new_line = insert_args (cmd->line); + std::string new_line = insert_user_defined_cmd_args (cmd->line); expression_up expr = parse_expression (new_line.c_str ()); ret = simple_control; @@ -551,7 +549,7 @@ execute_control_command (struct command_line *cmd) print_command_trace (buffer); /* Parse the conditional for the if statement. */ - std::string new_line = insert_args (cmd->line); + std::string new_line = insert_user_defined_cmd_args (cmd->line); expression_up expr = parse_expression (new_line.c_str ()); current = NULL; @@ -591,7 +589,7 @@ execute_control_command (struct command_line *cmd) { /* Breakpoint commands list, record the commands in the breakpoint's command list and return. */ - std::string new_line = insert_args (cmd->line); + std::string new_line = insert_user_defined_cmd_args (cmd->line); ret = commands_from_control_command (new_line.c_str (), cmd); break; } @@ -782,13 +780,12 @@ locate_arg (const char *p) return NULL; } -/* Insert the user defined arguments stored in user_arg into the $arg - arguments found in line. */ +/* See cli-script.h. */ -static std::string -insert_args (const char *line) +std::string +insert_user_defined_cmd_args (const char *line) { - /* If we are not in a user-defined function, treat $argc, $arg0, et + /* If we are not in a user-defined command, treat $argc, $arg0, et cetera as normal convenience variables. */ if (user_args == NULL) return line; diff --git a/gdb/cli/cli-script.h b/gdb/cli/cli-script.h index 7db6e82e6ff..8920d44fde4 100644 --- a/gdb/cli/cli-script.h +++ b/gdb/cli/cli-script.h @@ -53,6 +53,12 @@ extern struct cleanup * extern void execute_user_command (struct cmd_list_element *c, char *args); +/* If we're in a user-defined command, replace any $argc/$argN + reference found in LINE with the arguments that were passed to the + command. Otherwise, treat $argc/$argN as normal convenience + variables. */ +extern std::string insert_user_defined_cmd_args (const char *line); + /* Exported to top.c */ extern void print_command_trace (const char *cmd); diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog index dc8244c2d01..18564b6549e 100644 --- a/gdb/doc/ChangeLog +++ b/gdb/doc/ChangeLog @@ -1,3 +1,10 @@ +2016-12-02 Pedro Alves + + PR cli/20559 + * gdb.texinfo (Define): Add example of using "eval" to process a + variable number of arguments. + (Output) : Add anchor. + 2016-11-30 Simon Marchi * Makefile.in: Likewise. diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index 6ad27540092..f4dfac2047f 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -24096,6 +24096,21 @@ define adder end @end smallexample +Combining with the @code{eval} command (@pxref{eval}) makes it easier +to process a variable number of arguments: + +@smallexample +define adder + set $i = 0 + set $sum = 0 + while $i < $argc + eval "set $sum = $sum + $arg%d", $i + set $i = $i + 1 + end + print $sum +end +@end smallexample + @table @code @kindex define @@ -24526,6 +24541,7 @@ Here's an example of printing DFP types using the above conversion letters: printf "D32: %Hf - D64: %Df - D128: %DDf\n",1.2345df,1.2E10dd,1.2E1dl @end smallexample +@anchor{eval} @kindex eval @item eval @var{template}, @var{expressions}@dots{} Convert the values of one or more @var{expressions} under the control of diff --git a/gdb/printcmd.c b/gdb/printcmd.c index f434f5f70ab..bab13fb1d25 100644 --- a/gdb/printcmd.c +++ b/gdb/printcmd.c @@ -45,6 +45,7 @@ #include "charset.h" #include "arch-utils.h" #include "cli/cli-utils.h" +#include "cli/cli-script.h" #include "format.h" #include "source.h" @@ -2723,6 +2724,8 @@ eval_command (char *arg, int from_tty) std::string expanded = ui_file_as_string (ui_out); + expanded = insert_user_defined_cmd_args (expanded.c_str ()); + execute_command (&expanded[0], from_tty); do_cleanups (cleanups); diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 5a0330c618f..c6ee46279f3 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,10 @@ +2016-12-02 Pedro Alves + + PR cli/20559 + * gdb.base/commands.exp (user_defined_command_args_eval): New + procedure. + (top level): Call it. + 2016-12-02 Luis Machado * gdb.base/ovldbreak.exp (take_gdb_out_of_choice_menu): Restore diff --git a/gdb/testsuite/gdb.base/commands.exp b/gdb/testsuite/gdb.base/commands.exp index 8c06e8cb316..3308a9b9dd8 100644 --- a/gdb/testsuite/gdb.base/commands.exp +++ b/gdb/testsuite/gdb.base/commands.exp @@ -352,6 +352,36 @@ proc_with_prefix user_defined_command_test {} { "display user-defined empty command" } +# Test that "eval" in a user-defined command expands $argc/$argN. + +proc_with_prefix user_defined_command_args_eval {} { + global gdb_prompt + + gdb_test_multiple "define command_args_eval" \ + "define command_args_eval" { + -re "End with" { + pass "define" + } + } + + # Make a command that constructs references to $argc and $argN via + # eval. + gdb_test \ + [multi_line \ + {eval "printf \"argc = %%d,\", $arg%c", 'c'} \ + {set $i = 0} \ + {while $i < $argc} \ + { eval "printf \" %%d\", $arg%d", $i} \ + { set $i = $i + 1} \ + {end} \ + {printf "\n"} \ + {end}] \ + "" \ + "enter commands" + + gdb_test "command_args_eval 1 2 3" "argc = 3, 1 2 3" "execute command" +} + proc_with_prefix watchpoint_command_test {} { global gdb_prompt @@ -882,6 +912,7 @@ if_while_breakpoint_command_test infrun_breakpoint_command_test breakpoint_command_test user_defined_command_test +user_defined_command_args_eval watchpoint_command_test test_command_prompt_position deprecated_command_test -- 2.30.2