New opt.tcl file

Change-Id: I216dba59962093b448740f3c5be0b659952ca263
Signed-off-by: Michael Walsh <micwalsh@us.ibm.com>
diff --git a/lib/opt.tcl b/lib/opt.tcl
new file mode 100755
index 0000000..364282b
--- /dev/null
+++ b/lib/opt.tcl
@@ -0,0 +1,514 @@
+#!/usr/bin/wish
+
+# This file provides many valuable parm and argument processing procedures
+# such as longoptions, pos_parms, gen_get_options, etc.
+
+my_source [list escape.tcl data_proc.tcl print.tcl]
+
+
+proc get_arg_req { opt_name } {
+
+  # Determine whether the given opt_name is "optional", "required" or
+  # "not_allowed" and return that result.
+
+  # Note:  This procedure assumes that global list longoptions has been
+  # initialized via a call to the longoptions procedure.
+
+  # Description of argument(s):
+  # opt_name                        The name of the option including its
+  #                                 requirement indicator as accepted by the
+  #                                 bash getopt longoptions parameter: No
+  #                                 colon means the option takes no argument,
+  #                                 one colon means the option requires an
+  #                                 argument and two colons indicate that an
+  #                                 argument is optional (the value of the
+  #                                 option will be 1 if no argument is
+  #                                 specified.
+
+  global longoptions
+
+  if { [lsearch -exact $longoptions "${opt_name}::"] != -1 } {
+    return optional
+  }
+  if { [lsearch -exact $longoptions "${opt_name}:"] != -1 } {
+    return required
+  }
+  return not_allowed
+
+}
+
+
+proc longoptions { args } {
+
+  # Populate the global longoptions list and set global option variable
+  # defaults.
+
+  # Description of argument(s):
+  # args                            Each arg is comprised of 1) the name of
+  #                                 the option 2) zero, one or 2 colons to
+  #                                 indicate whether the corresponding
+  #                                 argument value is a) not required, b)
+  #                                 required or c) optional 3) Optionally, an
+  #                                 equal sign followed by a default value for
+  #                                 the parameter.
+
+  # Example usage:
+  # longoptions parm1 parm2: parm3:: test_mode:=0 quiet:=0
+
+  global longoptions
+
+  set debug 0
+  foreach arg $args {
+    # Create an option record which is a 2-element list consisting of the
+    # option specification and a possible default value.  Example:;
+    # opt_rec:
+    #   opt_rec[0]:      test_mode:
+    #   opt_rec[1]:      0
+    set opt_rec [split $arg =]
+    # opt_spec will include any colons that may have been specified.
+    set opt_spec [lindex $opt_rec 0]
+    # Add the option spec to the global longoptions list.
+    lappend_unique longoptions $opt_spec
+    # Strip the colons to get the option name.
+    set opt_name [string trimright $opt_spec ":"]
+    # Get the option's default value, if any.
+    set opt_default_value [lindex $opt_rec 1]
+    set arg_req [get_arg_req $opt_name]
+    if { $arg_req == "not_allowed" && $opt_default_value == "" } {
+      # If this parm takes no arg and no default was specified by the user,
+      # we will set the default to 0.
+      set opt_default_value 0
+    }
+    # Set a global variable whose name is identical to the option name.  Set
+    # the default value if there is one.
+    set cmd_buf "global ${opt_name} ; set ${opt_name} {${opt_default_value}}"
+    dpissuing
+    eval $cmd_buf
+  }
+
+}
+
+
+proc pos_parms { args } {
+
+  # Populate the global pos_parms list and set global option variable defaults.
+
+  # Description of argument(s):
+  # args                            Each arg is comprised of the name of a
+  #                                 positional parm and a possible initial
+  #                                 value.
+
+  # Example usage:
+  # pos_parms user_name=mike
+
+  global pos_parms
+
+  set pos_parms [list]
+  set debug 0
+  foreach arg $args {
+    dprint_var arg
+    # Create an option record which is a 2-element list consisting of the
+    # option specification and a possible default value.  Example:;
+    # opt_rec:
+    #   opt_rec[0]:      test_mode:
+    #   opt_rec[1]:      0
+    set parm_rec [split $arg =]
+    dprint_list parm_rec
+    # parm_spec will include any colons that may have been specified.
+    set parm_name [lindex $parm_rec 0]
+    dprint_var parm_name
+    # Add the option spec to the global pos_parms list.
+    lappend pos_parms $parm_name
+    # Get the option's default value, if any.
+    set parm_default_value [lindex $parm_rec 1]
+    dprint_var parm_default_value
+    # Set a global variable whose name is identical to the option name.  Set
+    # the default value if there is one.
+    set cmd_buf "global ${parm_name} ; set ${parm_name}"
+    append cmd_buf " {${parm_default_value}}"
+    dpissuing
+    eval $cmd_buf
+  }
+
+}
+
+
+proc gen_get_options { argv } {
+
+  # Get the command line options/arguments and use them to set the
+  # corresponding global option variable names.
+
+  # Note:  This procedure assumes that global list longoptions has been
+  # initialized via a call to the longoptions procedure and that global
+  # pos_parms has been initialized via a call to the pos_parms procdure.
+  # These data structures indicates what options and arguments are supported
+  # by the calling program.
+
+  # Note: If the last var_name in pos_parms ends in "_list", then the caller
+  # can specify as many parms as they desire and they will all be appended to
+  # the variable in question.
+
+  # Description of argument(s):
+  # argv                            The argv array that is set for this
+  #                                 program.
+
+  # Example call:
+  # gen_get_options $argv
+
+  global longoptions
+  global pos_parms
+  global program_name
+
+  set debug 0
+
+  set len_pos_parms [llength $pos_parms]
+
+  dprint_list longoptions
+  dprint_list pos_parms
+  dprint_var len_pos_parms
+
+  # Rather than write the algorithm from scratch, we will call upon the bash
+  # getopt program to help us.  This program has several advantages:
+  # - It will reject illegal options
+  # - It supports different posix input styles (e.g. -option <arg> vs
+  # --option=<arg>).
+  # - It allows the program's caller to abbreviate option names provided that
+  # there is no ambiguity.
+
+  # Convert curly braces to single quotes.  This includes escaping existing
+  # quotes in the argv string.  This will allow us to use the result in a bash
+  # command string.  Example: {--parm3=Kathy's cat} will become
+  # '--parm3=Kathy'\''s cat'.
+  dprint_var argv
+  set bash_args [curly_braces_to_quotes $argv]
+  set cmd_buf "getopt --name=${program_name} -a --longoptions=\"help"
+  append cmd_buf " ${longoptions}\" --options=\"-h\" -- ${bash_args}"
+  dpissuing
+  if { [ catch {set OPT_LIST [eval exec bash -c {$cmd_buf}]} result ] } {
+    puts stderr $result
+    exit 1
+  }
+
+  set OPT_LIST [quotes_to_curly_braces $OPT_LIST]
+  set cmd_buf "set opt_list \[list $OPT_LIST\]"
+  dpissuing
+  eval $cmd_buf
+
+  dprint_list opt_list
+
+  set longopt_regex {\-[-]?[^- ]+}
+  global help
+  global h
+  set help 0
+  set h 0
+  dprintn ; dprint_timen "Processing opt_list."
+  set pos_parm_ix 0
+  set current_longopt {}
+  foreach opt_list_entry $opt_list {
+    dprint_var opt_list_entry
+    if { $opt_list_entry == "--" } { break; }
+    if { $current_longopt != "" } {
+      dprint_var current_longopt
+      set cmd_buf "global ${current_longopt} ; set ${current_longopt}"
+      append cmd_buf " {${opt_list_entry}}"
+      dpissuing
+      eval $cmd_buf
+      set current_longopt {}
+      dprintn
+      continue
+    }
+    set is_option [regexp -expanded $longopt_regex ${opt_list_entry}]
+    dprint_var is_option
+    if { $is_option } {
+      regsub -all {^\-[-]?} $opt_list_entry {} opt_name
+      dprint_var opt_name
+      set arg_req [get_arg_req $opt_name]
+      dprint_var arg_req
+      if { $arg_req == "not_allowed" } {
+        set cmd_buf "global ${opt_name} ; set ${opt_name} 1"
+        dpissuing
+        eval $cmd_buf
+      } else {
+        set current_longopt [string trimleft $opt_list_entry "-"]
+      }
+    } else {
+      # Must be a positional parm.
+      if { $pos_parm_ix >= $len_pos_parms } {
+        set is_list [regexp -expanded "_list$" ${pos_parm_name}]
+        dprint_var is_list
+        if { $is_list } {
+          set cmd_buf "lappend ${pos_parm_name} {${opt_list_entry}}"
+          dpissuing
+          eval $cmd_buf
+          continue
+        }
+        append message "The caller has specified more positional parms than"
+        append message " are allowed by the program.\n"
+        append message [sprint_varx parm_value ${opt_list_entry} 2]
+        append message [sprint_list pos_parms 2]
+        print_error_report $message
+        exit 1
+      }
+      set pos_parm_name [lindex $pos_parms $pos_parm_ix]
+      set cmd_buf "global ${pos_parm_name} ; set ${pos_parm_name}"
+      append cmd_buf " {${opt_list_entry}}"
+      dpissuing
+      eval $cmd_buf
+      incr pos_parm_ix
+    }
+    dprintn
+  }
+
+  if { $h || $help } {
+    if { [info proc help] != "" } {
+      help
+    } else {
+      puts "No help text defined for this program."
+    }
+    exit 0
+  }
+
+}
+
+
+proc print_usage {} {
+
+  # Print usage help text line.
+
+  # Example:
+  # usage: demo.tcl [OPTIONS] [USERID] [FILE_LIST]
+
+  global program_name
+  global longoptions
+  global pos_parms
+
+  append buffer "usage: $program_name"
+
+  if { $longoptions != "" } {
+    append buffer " \[OPTIONS\]"
+  }
+
+  foreach parm $pos_parms {
+    set upper_parm [string toupper $parm]
+    append buffer " \[$upper_parm\]"
+  }
+
+  puts $buffer
+
+}
+
+
+proc print_option_help { option help_text { data_desc {} } { print_default {}}\
+  { width 30 } } {
+
+  # Print help text for the given option.
+
+  # Description of argument(s):
+  # option                          The option for which help text should be
+  #                                 printed.  This value should include a
+  #                                 leading "--" to indicate that this is an
+  #                                 optional rather than a positional parm.
+  # data_desc                       A description of the data (e.g. "dir
+  #                                 path", "1,0", etc.)0
+  # print_default                   Indicates whether the current value of the
+  #                                 global variable representing the option is
+  #                                 to be printed as a default value.  For
+  #                                 example, if the option value is "--parm1",
+  #                                 global value parm1 is "no" and
+  #                                 print_default is set, the following phrase
+  #                                 will be appended to the help text: The
+  #                                 default value is "no".
+  # width                           The width of the arguments column.
+
+  set indent 2
+
+  # Get the actual opt_name by stripping leading dashes and trailing colons.
+  regsub -all {^\-[-]?} $option {} opt_name
+  regsub -all {:[:]?$} $opt_name {} opt_name
+
+  # Set defaults for args to this procedure.
+  set longopt_regex {\-[-]?[^- ]+}
+  set is_option [regexp -expanded $longopt_regex ${option}]
+  if { $is_option } {
+    # It is an option (vs positional parm).
+    # Does it take an argument?
+    set arg_req [get_arg_req $opt_name]
+    if { $arg_req == "not_allowed" } {
+      set data_desc_default ""
+    } else {
+      set data_desc_default "{$opt_name}"
+    }
+  } else {
+    # It's a positional parm.
+    set opt_name [string tolower $opt_name]
+    set data_desc_default ""
+  }
+
+  set_var_default data_desc $data_desc_default
+  set_var_default print_default 1
+
+  if { $print_default } {
+    # Access the global variable that represents the value of the option.
+    eval global $opt_name
+    set cmd_buf "set opt_value \${${opt_name}}"
+    eval $cmd_buf
+    set default_string "  The default value is \"${opt_value}\"."
+  } else {
+    set default_string ""
+  }
+
+  if { $data_desc != "" } {
+    # Remove any curly braces and put them back on.
+    set data_desc "{[string trim $data_desc {{}}]}"
+  }
+
+  print_arg_desc "$option $data_desc" "${help_text}${default_string}" 2 $width
+
+}
+
+
+# Create help text variables for stock parms like quiet, debug and test_mode.
+set test_mode_help_text "This means that ${program_name} should go through"
+append test_mode_help_text " all the motions but not actually do anything"
+append test_mode_help_text " substantial. This is mainly to be used by the"
+append test_mode_help_text " developer of ${program_name}."
+set quiet_help_text "If this parameter is set to \"1\", ${program_name} will"
+append quiet_help_text " print only essential information, i.e. it will not"
+append quiet_help_text " echo parameters, echo commands, print the total run"
+append quiet_help_text " time, etc."
+set debug_help_text "If this parameter is set to \"1\", ${program_name} will"
+append debug_help_text " print additional debug information. This is mainly to"
+append debug_help_text " be used by the developer of ${program_name}."
+
+proc gen_print_help { { width 30 } } {
+
+  # Print general help text based on user's pos_parms and longoptions.
+
+  # Note: To use this procedure, the user must create a global help_dict
+  # containing entries for each of their options and one for the program as a
+  # whole.  The keys of this dictionary are the option names and the values
+  # are lists whose values map to arguments from the print_option_help
+  # procedure:
+  # - help_text
+  # - data_desc (optional)
+  # - print_default (1 or 0 - default is 1)
+
+  #  Example:
+  # set help_dict [dict create\
+  #   ${program_name} [list "${program_name} will demonstrate..."]\
+  #   userid [list "The userid of the caller."]\
+  #   file_list [list "A list of files to be processed."]\
+  #   flag [list "A flag to indicate that..."]\
+  #   dir_path [list "The path to the directory containing the files."]\
+  #   release [list "The code release."]\
+  # ]
+
+  global program_name
+  global longoptions
+  global pos_parms
+
+  global help_dict
+  global test_mode_help_text
+  global quiet_help_text
+  global debug_help_text
+
+  # Add help text for stock options to global help_dict.
+  dict set help_dict test_mode [list $test_mode_help_text "1,0"]
+  dict set help_dict quiet [list $quiet_help_text "1,0"]
+  dict set help_dict debug [list $debug_help_text "1,0"]
+
+  puts ""
+  print_usage
+
+  # Retrieve the general program help text from the help_dict and print it.
+  set help_entry [dict get $help_dict ${program_name}]
+  puts ""
+  puts [lindex $help_entry 0]
+
+  if { $pos_parms != "" } {
+    puts ""
+    puts "positional arguments:"
+    foreach option $pos_parms {
+      # Retrieve the print_option_help parm values from the help_dict and
+      # call print_option_help.
+      set help_entry [dict get $help_dict ${option}]
+      set help_text [lindex $help_entry 0]
+      set data_desc [lindex $help_entry 1]
+      set print_default [lindex $help_entry 2]
+      print_option_help [string toupper $option] $help_text $data_desc\
+          $print_default $width
+    }
+  }
+
+  if { $longoptions != "" } {
+    puts ""
+    puts "optional arguments:"
+    foreach option $longoptions {
+      set option [string trim $option ":"]
+      # Retrieve the print_option_help parm values from the help_dict and
+      # call print_option_help.
+      set help_entry [dict get $help_dict ${option}]
+      set help_text [lindex $help_entry 0]
+      set data_desc [lindex $help_entry 1]
+      set print_default [lindex $help_entry 2]
+      print_option_help "--${option}" $help_text $data_desc $print_default\
+        $width
+    }
+  }
+  puts ""
+
+}
+
+
+proc return_program_options {} {
+
+  # Return all the names of the global program options as a composite list.
+
+  global longoptions pos_parms
+
+  regsub -all {:} $longoptions {} program_options
+  eval lappend program_options $pos_parms
+
+  return $program_options
+
+}
+
+
+proc global_program_options {} {
+
+  # Make all program option global variables available to the calling function.
+  set program_options [return_program_options]
+  uplevel eval global $program_options
+
+}
+
+
+proc gen_pre_validation {} {
+
+  # Do generic post-validation processing.  By "post", we mean that this is
+  # to be called from a validation function after the caller has done any
+  # validation desired.  If the calling program passes exit_function and
+  # signal_handler parms, this function will register them.  In other words,
+  # it will make the signal_handler functions get called for SIGINT and
+  # SIGTERM and will make the exit_function function run prior to the
+  # termination of the program.
+
+  # Make all program option global variables available to the calling function.
+  uplevel global_program_options
+
+}
+
+
+proc gen_post_validation {} {
+
+  # Do generic post-validation processing.  By "post", we mean that this is
+  # to be called from a validation function after the caller has done any
+  # validation desired.  If the calling program passes exit_function and
+  # signal_handler parms, this function will register them.  In other words,
+  # it will make the signal_handler functions get called for SIGINT and
+  # SIGTERM and will make the exit_function function run prior to the
+  # termination of the program.
+
+  trap { exit_proc } [list SIGTERM SIGINT]
+
+}