modules/FvwmConsole/getline.c

   1 /* -*-c-*- */
   2 /* This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License as published by
   4  * the Free Software Foundation; either version 2 of the License, or
   5  * (at your option) any later version.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this program; if not, write to the Free Software
  14  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  15  */
  16
  17 #include "config.h"
  18
  19 #include "FvwmConsole.h"
  20
  21 #ifdef HAVE_READLINE
  22 #include <readline/readline.h>
  23 #include <readline/history.h>
  24 #define fvwm_rl_bind_key(x, y) rl_bind_key(x, y)
  25 #define fvwm_readline(x) readline(x)
  26 #define fvwm_add_history(cmd) add_history(cmd)
  27 #define fvwm_stifle_history(x) stifle_history(x)
  28 #define fvwm_read_history(x) read_history(x)
  29 #define fvwm_write_history(x) write_history(x)
  30 #ifdef HAVE_GNU_READLINE
  31 #define fvwm_append_history(x, y) append_history(x, y)
  32 #define fvwm_history_truncate_file(x, y) history_truncate_file(x, y)
  33 #define fvwm_read_history_range(x, y, z) read_history_range(x, y, z)
  34 #else
  35 #define fvwm_append_history(x, y) -1
  36 #define fvwm_history_truncate_file(x, y) -1
  37 #define fvwm_read_history_range(x, y, z) -1
  38 #endif
  39 #define USE_READLINE 1
  40 #else
  41 #define fvwm_rl_bind_key(x, y) -1
  42 #define fvwm_readline(x) NULL
  43 #define fvwm_add_history(cmd)
  44 #define fvwm_append_history(x, y) -1
  45 #define fvwm_history_truncate_file(x, y) -1
  46 #define fvwm_read_history_range(x, y, z) -1
  47 #define fvwm_stifle_history(x)
  48 #define fvwm_read_history(x) -1
  49 #define fvwm_write_history(x) -1
  50 #define USE_READLINE 0
  51 #endif
  52
  53 static char cmd[MAX_COMMAND_SIZE];
  54 static char *line = (char *)NULL;
  55 static int done_init = 0;
  56 static char *h_file;
  57
  58 char *get_line(void)
  59 {
  60         char *prompt;
  61         int len;
  62         char *home;
  63         int fdh;
  64
  65         if (USE_READLINE == 0)
  66         {
  67                 if (fgets(cmd, MAX_COMMAND_SIZE, stdin) == NULL)
  68                 {
  69                         return NULL;
  70                 }
  71
  72                 return cmd;
  73         }
  74         /* If initialization hasn't been done, do it now:
  75          *  - We don't want TAB completion
  76          */
  77         if (!done_init)
  78         {
  79                 (void)fvwm_rl_bind_key('\t', rl_insert);
  80                 /* get history from file */
  81                 home = getenv("FVWM_USERDIR");
  82                 h_file = safemalloc(strlen(home) + sizeof(HISTFILE) + 1);
  83                 strcpy(h_file, home);
  84                 strcat(h_file, HISTFILE);
  85                 fvwm_stifle_history(HISTSIZE);
  86                 if (access(h_file, F_OK)  < 0)
  87                 {
  88                         /* if it doesn't exist create it */
  89                         fdh = creat(h_file, S_IRUSR | S_IWUSR);
  90                         if (fdh != -1)
  91                         {
  92                                 close(fdh);
  93                         }
  94                 }
  95                 else
  96                 {
  97                         (void)fvwm_read_history(h_file);
  98                 }
  99                 done_init = 1;
 100         }
 101         /* Empty out the previous info */
 102         len = 0;
 103         *cmd = '\0';
 104         prompt = PS1;
 105         while (1)
 106         {
 107                 int linelen = 0;
 108
 109                 /* If the buffer has already been allocated, free the memory.
 110                  */
 111                 if (line != (char *)NULL)
 112                 {
 113                         free(line);
 114                 }
 115
 116                 /* Get a line from the user. */
 117                 line  = fvwm_readline(prompt);
 118                 if (line == NULL)
 119                 {
 120                         return NULL;
 121                 }
 122
 123                 /* Make sure we have enough space for the new line */
 124                 linelen = strlen(line);
 125                 if (len + linelen > MAX_COMMAND_SIZE-2)
 126                 {
 127                         fprintf(
 128                                 stderr, "line too long %d chars max %d \a\n",
 129                                 len + linelen, MAX_COMMAND_SIZE - 2);
 130                         strncat(cmd, line, MAX_COMMAND_SIZE - len - 2);
 131                         fvwm_add_history(cmd);
 132                         break;
 133                 }
 134
 135                 /* Copy the new line onto the end of the current line */
 136                 strcat(cmd, line);
 137                 /* If the current line doesn't end with a backslash, we're done
 138                  */
 139                 len = strlen(cmd);
 140                 if (cmd[len-1] != '\\')
 141                 {
 142                         break;
 143                 }
 144                 /* Otherwise, remove it and wait for more (add a space if
 145                  * needed) */
 146                 prompt = PS2;
 147                 cmd[len-1] =
 148                         (cmd[len-2] == ' ' || cmd[len-2] == '\t') ? '\0' : ' ';
 149         }
 150         /* If the command has any text in it, save it on the history. */
 151         if (*cmd != '\0')
 152         {
 153                 fvwm_add_history(cmd);
 154                 if (fvwm_append_history(1, h_file) == 0)
 155                 {
 156                         (void)fvwm_history_truncate_file(h_file, HISTSIZE);
 157                 }
 158                 else
 159                 {
 160                         (void)fvwm_write_history(h_file);
 161                 }
 162         }
 163         cmd[len]   = '\n';
 164         cmd[len+1] = '\0';
 165
 166         return cmd;
 167 }