diplodocus.org Git - nmh/blob - sbr/read_switch_multiword_via_readline.c

   1 /*
   2  * read_switch_multiword_via_readline.c -- get an answer from the user, with readline
   3  *
   4  * This code is Copyright (c) 2012, by the authors of nmh.  See the
   5  * COPYRIGHT file in the root directory of the nmh distribution for
   6  * complete copyright information.
   7  */
   8
   9 #include <h/mh.h>
  10
  11 #ifdef READLINE_SUPPORT
  12 #include <readline/readline.h>
  13 #include <readline/history.h>
  14
  15 static struct swit *rl_cmds;
  16
  17 static char *nmh_command_generator(const char *, int);
  18 static char **nmh_completion(const char *, int, int);
  19 static void initialize_readline(void);
  20
  21 static char ansbuf[BUFSIZ];
  22
  23 /*
  24  * getans, but with readline support
  25  */
  26
  27 char **
  28 read_switch_multiword_via_readline(char *prompt, struct swit *ansp)
  29 {
  30     char *ans, **cpp;
  31
  32     initialize_readline();
  33     rl_cmds = ansp;
  34
  35     for (;;) {
  36         ans = readline(prompt);
  37         /*
  38          * If we get an EOF, return
  39          */
  40
  41         if (ans == NULL)
  42             return NULL;
  43
  44         if (ans[0] == '?' || ans[0] == '\0') {
  45             puts("Options are:");
  46             print_sw(ALL, ansp, "", stdout);
  47             free(ans);
  48             continue;
  49         }
  50         add_history(ans);
  51         strncpy(ansbuf, ans, sizeof(ansbuf));
  52         ansbuf[sizeof(ansbuf) - 1] = '\0';
  53         cpp = brkstring(ansbuf, " ", NULL);
  54         switch (smatch(*cpp, ansp)) {
  55             case AMBIGSW:
  56                 ambigsw(*cpp, ansp);
  57                 continue;
  58             case UNKWNSW:
  59                 printf(" -%s unknown. Hit <CR> for help.\n", *cpp);
  60                 continue;
  61             default:
  62                 free(ans);
  63                 return cpp;
  64         }
  65         free(ans);
  66     }
  67 }
  68
  69 static void
  70 initialize_readline(void)
  71 {
  72     rl_readline_name = "Nmh";
  73     rl_attempted_completion_function = nmh_completion;
  74 }
  75
  76 static char **
  77 nmh_completion(const char *text, int start, int end)
  78 {
  79     char **matches;
  80
  81     NMH_UNUSED (end);
  82
  83     matches = (char **) NULL;
  84
  85     if (start == 0)
  86         matches = rl_completion_matches(text, nmh_command_generator);
  87
  88     return matches;
  89 }
  90
  91 static char *
  92 nmh_command_generator(const char *text, int state)
  93 {
  94     static int list_index, len;
  95     char *name, *p;
  96     char buf[256];
  97
  98     if (!state) {
  99         list_index = 0;
 100         len = strlen(text);
 101     }
 102
 103     while ((name = rl_cmds[list_index].sw)) {
 104         list_index++;
 105         strncpy(buf, name, sizeof(buf));
 106         buf[sizeof(buf) - 1] = '\0';
 107         p = *brkstring(buf, " ", NULL);
 108         if (strncmp(p, text, len) == 0)
 109             return strdup(p);
 110     }
 111
 112     return NULL;
 113 }
 114 #endif /* READLINE_SUPPORT */