1 /*
2  * Copyright (c) 2022 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "compat.h"
18 
19 #if !HAVE_READLINE
20 
21 #include <stdio.h>
22 #include <string.h>
23 
24 char *
25 readline(const char *prompt)
26 {
27 	char *ch, *line = NULL;
28 	size_t linesize = 0;
29 	ssize_t linelen;
30 
31 	printf("%s", prompt);
32 	fflush(stdout);
33 
34 	linelen = getline(&line, &linesize, stdin);
35 	if (linelen == -1)
36 		return NULL;
37 
38 	if ((ch = strchr(line, '\n')) != NULL)
39 		*ch = '\0';
40 	return line;
41 }
42 
43 void
44 add_history(const char *line)
45 {
46 	return;
47 }
48 
49 void
50 compl_setup(void)
51 {
52 	return;
53 }
54 
55 #else /* HAVE_READLINE */
56 
57 #include <ctype.h>
58 #include <limits.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 
63 #include <readline/readline.h>
64 #include <readline/history.h>
65 
66 #include "kami.h"
67 #include "kamiftp.h"
68 
69 struct compl_state {
70 	size_t		  size;
71 	size_t		  len;
72 	char		**entries;
73 };
74 
75 static struct compl_state compl_state;
76 static char compl_prfx[PATH_MAX];
77 
78 static void
79 compl_state_reset(void)
80 {
81 	size_t i;
82 
83 	for (i = 0; i < compl_state.len; ++i)
84 		free(compl_state.entries[i]);
85 	free(compl_state.entries);
86 
87 	memset(&compl_state, 0, sizeof(compl_state));
88 }
89 
90 static int
91 compl_add_entry(const struct np_stat *st)
92 {
93 	const char	*sufx = "";
94 	char		*dup;
95 
96 	if (compl_state.len == compl_state.size) {
97 		size_t newsz = compl_state.size * 1.5;
98 		void *t;
99 
100 		if (newsz == 0)
101 			newsz = 16;
102 
103 		/* one for the NULL entry at the end */
104 		t = recallocarray(compl_state.entries, compl_state.size,
105 		    newsz + 1, sizeof(char *));
106 		if (t == NULL)
107 			return -1;
108 		compl_state.entries = t;
109 		compl_state.size = newsz;
110 	}
111 
112 	if (st->qid.type & QTDIR)
113 		sufx = "/";
114 
115 	if (asprintf(&dup, "%s%s%s", compl_prfx, st->name, sufx) == -1)
116 		return -1;
117 	compl_state.entries[compl_state.len++] = dup;
118 	return 0;
119 }
120 
121 static void
122 cleanword(char *buf, int brkspc)
123 {
124 	char	*cmd;
125 	int	 escape, quote;
126 
127 	while (brkspc && isspace((unsigned char)*buf))
128 		memmove(buf, buf + 1, strlen(buf));
129 
130 	escape = quote = 0;
131 	for (cmd = buf; *cmd != '\0'; ++cmd) {
132 		if (escape) {
133 			escape = 0;
134 			continue;
135 		}
136 		if (*cmd == '\\')
137 			goto skip;
138 		if (*cmd == quote) {
139 			quote = 0;
140 			goto skip;
141 		}
142 		if (*cmd == '\'' || *cmd == '"') {
143 			quote = *cmd;
144 			goto skip;
145 		}
146 		if (quote)
147 			continue;
148 		if (brkspc && isspace((unsigned char)*cmd))
149 			break;
150 		continue;
151 
152 	skip:
153 		memmove(cmd, cmd + 1, strlen(cmd));
154 		cmd--;
155 	}
156 	*cmd = '\0';
157 }
158 
159 static int
160 tellcmd(char *buf)
161 {
162 	size_t i;
163 
164 	cleanword(buf, 1);
165 	for (i = 0; i < nitems(cmds); ++i) {
166 		if (!strcmp(cmds[i].name, buf))
167 			return cmds[i].cmdtype;
168 	}
169 
170 	return CMD_UNKNOWN;
171 }
172 
173 static int
174 tell_argno(const char *cmd, int *cmdtype)
175 {
176 	char		 cmd0[64];	/* plenty of space */
177 	const char	*start = cmd;
178 	int		 escape, quote;
179 	int		 argno = 0;
180 
181 	*cmdtype = CMD_UNKNOWN;
182 
183 	/* find which argument needs to be completed */
184 	while (*cmd) {
185 		while (isspace((unsigned char)*cmd))
186 			cmd++;
187 		if (*cmd == '\0')
188 			break;
189 
190 		escape = quote = 0;
191 		for (; *cmd; ++cmd) {
192 			if (escape) {
193 				escape = 0;
194 				continue;
195 			}
196 			if (*cmd == '\\') {
197 				escape = 1;
198 				continue;
199 			}
200 			if (*cmd == quote) {
201 				quote = 0;
202 				continue;
203 			}
204 			if (*cmd == '\'' || *cmd == '\"') {
205 				quote = *cmd;
206 				continue;
207 			}
208 			if (quote)
209 				continue;
210 			if (isspace((unsigned char)*cmd))
211 				break;
212 		}
213 		if (isspace((unsigned char)*cmd))
214 			argno++;
215 
216 		if (argno == 1 && strlcpy(cmd0, start, sizeof(cmd0)) <
217 		    sizeof(cmd0))
218 			*cmdtype = tellcmd(cmd0);
219 	}
220 
221 	return argno;
222 }
223 
224 static char *
225 ftp_cmdname_generator(const char *text, int state)
226 {
227 	static size_t	 i, len;
228 	struct cmd	*cmd;
229 
230 	if (state == 0) {
231 		i = 0;
232 		len = strlen(text);
233 	}
234 
235 	while (i < nitems(cmds)) {
236 		cmd = &cmds[i++];
237 		if (strncmp(text, cmd->name, len) == 0)
238 			return strdup(cmd->name);
239 	}
240 
241 	return NULL;
242 }
243 
244 static char *
245 ftp_bool_generator(const char *text, int state)
246 {
247 	static const char	*toks[] = { "on", "off" };
248 	static size_t		 i, len;
249 	const char		*tok;
250 
251 	if (state == 0) {
252 		i = 0;
253 		len = strlen(text);
254 	}
255 
256 	while ((tok = toks[i++]) != NULL) {
257 		if (strncmp(text, tok, len) == 0)
258 			return strdup(tok);
259 	}
260 	return NULL;
261 }
262 
263 static char *
264 ftp_dirent_generator(const char *text, int state)
265 {
266 	static size_t	 i, len;
267 	const char	*entry;
268 
269 	if (state == 0) {
270 		i = 0;
271 		len = strlen(text);
272 	}
273 
274 	while (i < compl_state.len) {
275 		entry = compl_state.entries[i++];
276 		if (strncmp(text, entry, len) == 0)
277 			return strdup(entry);
278 	}
279 	return NULL;
280 }
281 
282 static char **
283 ftp_remote_files(const char *text, int start, int end)
284 {
285 	const char	*dir;
286 	char		 t[PATH_MAX];
287 	char		*s, *e;
288 
289 	strlcpy(t, text, sizeof(t));
290 	cleanword(t, 0);
291 
292 	if (!strcmp(t, "..")) {
293 		char **cs;
294 		if ((cs = calloc(2, sizeof(*cs))) == NULL)
295 			return NULL;
296 		cs[0] = strdup("../");
297 		return cs;
298 	}
299 
300 	s = t;
301 	if (!strncmp(s, "./", 2)) {
302 		s++;
303 		while (*s == '/')
304 			s++;
305 	}
306 
307 	if ((e = strrchr(s, '/')) != NULL)
308 		e[1] = '\0';
309 	dir = t;
310 
311 	if (!strcmp(dir, "."))
312 		strlcpy(compl_prfx, "", sizeof(compl_prfx));
313 	else
314 		strlcpy(compl_prfx, dir, sizeof(compl_prfx));
315 
316 	compl_state_reset();
317 	if (dir_listing(dir, compl_add_entry, 0) == -1)
318 		return NULL;
319 	return rl_completion_matches(text, ftp_dirent_generator);
320 }
321 
322 static char **
323 ftp_completion(const char *text, int start, int end)
324 {
325 	int	 argno, cmdtype;
326 	char	*line;
327 
328 	/* don't fall back on the default completion system by default */
329 	rl_attempted_completion_over = 1;
330 
331 	/* append a space after selecting a command */
332 	rl_completion_append_character = ' ';
333 
334 	if ((line = rl_copy_text(0, start)) == NULL)
335 		return NULL;
336 
337 	argno = tell_argno(line, &cmdtype);
338 	free(line);
339 	if (argno == 0)
340 		return rl_completion_matches(text, ftp_cmdname_generator);
341 
342 	/* but not for file completions */
343 	rl_completion_append_character = '\0';
344 
345 	switch (cmdtype) {
346 	case CMD_BELL:
347 	case CMD_HEXDUMP:
348 	case CMD_VERBOSE:
349 		if (argno != 1)
350 			return NULL;
351 		return rl_completion_matches(text, ftp_bool_generator);
352 
353 	case CMD_BYE:
354 	case CMD_LPWD:
355 		/* no args */
356 		return NULL;
357 
358 	case CMD_CD:
359 	case CMD_EDIT:
360 	case CMD_LS:
361 	case CMD_PAGE:
362 		if (argno != 1)
363 			return NULL;
364 		/* fallthrough */
365 	case CMD_RM:
366 		return ftp_remote_files(text, start, end);
367 
368 	case CMD_GET:
369 		if (argno > 2)
370 			return NULL;
371 		if (argno == 2)
372 			return ftp_remote_files(text, start, end);
373 		/* try local */
374 		rl_attempted_completion_over = 0;
375 		return NULL;
376 
377 	case CMD_LCD:
378 		if (argno != 1)
379 			return NULL;
380 		/* try local  */
381 		rl_attempted_completion_over = 0;
382 		return NULL;
383 
384 	case CMD_PIPE:
385 		if (argno > 2)
386 			return NULL;
387 		if (argno == 1)
388 			return ftp_remote_files(text, start, end);
389 		/* try local */
390 		rl_attempted_completion_over = 0;
391 		return NULL;
392 
393 	case CMD_PUT:
394 		if (argno > 2)
395 			return NULL;
396 		if (argno == 1) {
397 			/* try local */
398 			rl_attempted_completion_over = 0;
399 			return NULL;
400 		}
401 		return ftp_remote_files(text, start, end);
402 
403 	case CMD_RENAME:
404 		if (argno > 2)
405 			return NULL;
406 		return ftp_remote_files(text, start, end);
407 	}
408 
409 	return NULL;
410 }
411 
412 static int
413 ftp_quoted(char *line, int index)
414 {
415 	if (index > 0 && line[index - 1] == '\\')
416 		return !ftp_quoted(line, index - 1);
417 	return 0;
418 }
419 
420 void
421 compl_setup(void)
422 {
423 	rl_attempted_completion_function = ftp_completion;
424 	rl_completer_word_break_characters = "\t ";
425 	rl_completer_quote_characters = "\"'";
426 	rl_char_is_quoted_p = ftp_quoted;
427 }
428 
429 #endif