variables.c revision 21495
1/* variables.c -- How to manipulate user visible variables in Info. */ 2 3/* This file is part of GNU Info, a program for reading online documentation 4 stored in Info format. 5 6 Copyright (C) 1993 Free Software Foundation, Inc. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 2, or (at your option) 11 any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 21 22 Written by Brian Fox (bfox@ai.mit.edu). */ 23 24#include "info.h" 25#include "variables.h" 26 27/* **************************************************************** */ 28/* */ 29/* User Visible Variables in Info */ 30/* */ 31/* **************************************************************** */ 32 33/* Choices used by the completer when reading a zero/non-zero value for 34 a variable. */ 35static char *on_off_choices[] = { "Off", "On", (char *)NULL }; 36 37VARIABLE_ALIST info_variables[] = { 38 { "automatic-footnotes", 39 "When \"On\", footnotes appear and disappear automatically", 40 &auto_footnotes_p, (char **)on_off_choices }, 41 42 { "automatic-tiling", 43 "When \"On\", creating or deleting a window resizes other windows", 44 &auto_tiling_p, (char **)on_off_choices }, 45 46 { "visible-bell", 47 "When \"On\", flash the screen instead of ringing the bell", 48 &terminal_use_visible_bell_p, (char **)on_off_choices }, 49 50 { "errors-ring-bell", 51 "When \"On\", errors cause the bell to ring", 52 &info_error_rings_bell_p, (char **)on_off_choices }, 53 54 { "gc-compressed-files", 55 "When \"On\", Info garbage collects files which had to be uncompressed", 56 &gc_compressed_files, (char **)on_off_choices }, 57 { "show-index-match", 58 "When \"On\", the portion of the matched search string is highlighted", 59 &show_index_match, (char **)on_off_choices }, 60 61 { "scroll-behaviour", 62 "Controls what happens when scrolling is requested at the end of a node", 63 &info_scroll_behaviour, (char **)info_scroll_choices }, 64 65 { "scroll-step", 66 "The number lines to scroll when the cursor moves out of the window", 67 &window_scroll_step, (char **)NULL }, 68 69 { "ISO-Latin", 70 "When \"On\", Info accepts and displays ISO Latin characters", 71 &ISO_Latin_p, (char **)on_off_choices }, 72 73 { (char *)NULL, (char *)NULL, (int *)NULL, (char **)NULL } 74}; 75 76DECLARE_INFO_COMMAND (describe_variable, "Explain the use of a variable") 77{ 78 VARIABLE_ALIST *var; 79 char *description; 80 81 /* Get the variable's name. */ 82 var = read_variable_name ("Describe variable: ", window); 83 84 if (!var) 85 return; 86 87 description = (char *)xmalloc (20 + strlen (var->name) + strlen (var->doc)); 88 89 if (var->choices) 90 sprintf (description, "%s (%s): %s.", 91 var->name, var->choices[*(var->value)], var->doc); 92 else 93 sprintf (description, "%s (%d): %s.", var->name, *(var->value), var->doc); 94 95 window_message_in_echo_area ("%s", description); 96 free (description); 97} 98 99DECLARE_INFO_COMMAND (set_variable, "Set the value of an Info variable") 100{ 101 VARIABLE_ALIST *var; 102 char *line; 103 104 /* Get the variable's name and value. */ 105 var = read_variable_name ("Set variable: ", window); 106 107 if (!var) 108 return; 109 110 /* Read a new value for this variable. */ 111 { 112 char prompt[100]; 113 114 if (!var->choices) 115 { 116 int potential_value; 117 118 if (info_explicit_arg || count != 1) 119 potential_value = count; 120 else 121 potential_value = *(var->value); 122 123 sprintf (prompt, "Set %s to value (%d): ", 124 var->name, potential_value); 125 line = info_read_in_echo_area (active_window, prompt); 126 127 /* If no error was printed, clear the echo area. */ 128 if (!info_error_was_printed) 129 window_clear_echo_area (); 130 131 /* User aborted? */ 132 if (!line) 133 return; 134 135 /* If the user specified a value, get that, otherwise, we are done. */ 136 canonicalize_whitespace (line); 137 if (*line) 138 *(var->value) = atoi (line); 139 else 140 *(var->value) = potential_value; 141 142 free (line); 143 } 144 else 145 { 146 register int i; 147 REFERENCE **array = (REFERENCE **)NULL; 148 int array_index = 0; 149 int array_slots = 0; 150 151 for (i = 0; var->choices[i]; i++) 152 { 153 REFERENCE *entry; 154 155 entry = (REFERENCE *)xmalloc (sizeof (REFERENCE)); 156 entry->label = strdup (var->choices[i]); 157 entry->nodename = (char *)NULL; 158 entry->filename = (char *)NULL; 159 160 add_pointer_to_array 161 (entry, array_index, array, array_slots, 10, REFERENCE *); 162 } 163 164 sprintf (prompt, "Set %s to value (%s): ", 165 var->name, var->choices[*(var->value)]); 166 167 /* Ask the completer to read a variable value for us. */ 168 line = info_read_completing_in_echo_area (window, prompt, array); 169 170 info_free_references (array); 171 172 if (!echo_area_is_active) 173 window_clear_echo_area (); 174 175 /* User aborted? */ 176 if (!line) 177 { 178 info_abort_key (active_window, 0, 0); 179 return; 180 } 181 182 /* User accepted default choice? If so, no change. */ 183 if (!*line) 184 { 185 free (line); 186 return; 187 } 188 189 /* Find the choice in our list of choices. */ 190 for (i = 0; var->choices[i]; i++) 191 if (strcmp (var->choices[i], line) == 0) 192 break; 193 194 if (var->choices[i]) 195 *(var->value) = i; 196 } 197 } 198} 199 200/* Read the name of an Info variable in the echo area and return the 201 address of a VARIABLE_ALIST member. A return value of NULL indicates 202 that no variable could be read. */ 203VARIABLE_ALIST * 204read_variable_name (prompt, window) 205 char *prompt; 206 WINDOW *window; 207{ 208 register int i; 209 char *line; 210 REFERENCE **variables; 211 212 /* Get the completion array of variable names. */ 213 variables = make_variable_completions_array (); 214 215 /* Ask the completer to read a variable for us. */ 216 line = 217 info_read_completing_in_echo_area (window, prompt, variables); 218 219 info_free_references (variables); 220 221 if (!echo_area_is_active) 222 window_clear_echo_area (); 223 224 /* User aborted? */ 225 if (!line) 226 { 227 info_abort_key (active_window, 0, 0); 228 return ((VARIABLE_ALIST *)NULL); 229 } 230 231 /* User accepted "default"? (There is none.) */ 232 if (!*line) 233 { 234 free (line); 235 return ((VARIABLE_ALIST *)NULL); 236 } 237 238 /* Find the variable in our list of variables. */ 239 for (i = 0; info_variables[i].name; i++) 240 if (strcmp (info_variables[i].name, line) == 0) 241 break; 242 243 if (!info_variables[i].name) 244 return ((VARIABLE_ALIST *)NULL); 245 else 246 return (&(info_variables[i])); 247} 248 249/* Make an array of REFERENCE which actually contains the names of the 250 variables available in Info. */ 251REFERENCE ** 252make_variable_completions_array () 253{ 254 register int i; 255 REFERENCE **array = (REFERENCE **)NULL; 256 int array_index = 0, array_slots = 0; 257 258 for (i = 0; info_variables[i].name; i++) 259 { 260 REFERENCE *entry; 261 262 entry = (REFERENCE *)xmalloc (sizeof (REFERENCE)); 263 entry->label = strdup (info_variables[i].name); 264 entry->nodename = (char *)NULL; 265 entry->filename = (char *)NULL; 266 267 add_pointer_to_array 268 (entry, array_index, array, array_slots, 200, REFERENCE *); 269 } 270 271 return (array); 272} 273