2 * This file is part of DisOrder
3 * Copyright (C) 2008 Richard Kettlewell
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
19 /** @file lib/macros-builtin.c
20 * @brief Built-in expansions
22 * This is a grab-bag of non-domain-specific expansions
24 * Documentation is generated from the comments at the head of each function.
25 * The comment should have a '$' and the expansion name on the first line and
26 * should have a blank line between each paragraph.
28 * To make a bulleted list, put a '-' at the start of each line.
30 * You can currently get away with troff markup but this is horribly ugly and
54 static struct vector include_path
;
56 /** @brief Return 1 if @p s is 'true' else 0 */
57 int mx_str2bool(const char *s
) {
58 return !strcmp(s
, "true");
61 /** @brief Return "true" if @p n is nonzero else "false" */
62 const char *mx_bool2str(int n
) {
63 return n ?
"true" : "false";
66 /** @brief Write a boolean result */
67 int mx_bool_result(struct sink
*output
, int result
) {
68 if(sink_writes(output
, mx_bool2str(result
)) < 0)
74 /** @brief Search the include path */
75 char *mx_find(const char *name
, int report
) {
80 if(access(name
, O_RDONLY
) < 0) {
82 error(errno
, "cannot read %s", name
);
87 /* Search the include path */
88 for(n
= 0; n
< include_path
.nvec
; ++n
) {
89 byte_xasprintf(&path
, "%s/%s", include_path
.vec
[n
], name
);
90 if(access(path
, O_RDONLY
) == 0)
93 if(n
>= include_path
.nvec
) {
95 error(0, "cannot find '%s' in search path", name
);
102 /*$ @include{TEMPLATE}
106 * TEMPLATE can be an absolute filename starting with a '/'; only the file with
107 * exactly this name will be included.
109 * Alternatively it can be a relative filename, not starting with a '/'. In
110 * this case the file will be searched for in the include path. When searching
111 * paths, unreadable files are treated as if they do not exist (rather than
112 * matching then producing an error).
114 * If the name chosen ends ".tmpl" then the file will be expanded as a
115 * template. Anything else is included byte-for-byte without further
118 * Only regular files are allowed (no devices, sockets or name pipes).
120 static int exp_include(int attribute((unused
)) nargs
,
129 if(!(path
= mx_find(args
[0], 1/*report*/))) {
130 if(sink_printf(output
, "[[cannot find '%s']]", args
[0]) < 0)
134 /* If it's a template expand it */
135 if(strlen(path
) >= 5 && !strncmp(path
+ strlen(path
) - 5, ".tmpl", 5))
136 return mx_expand_file(path
, output
, u
);
137 /* Read the raw file. As with mx_expand_file() we insist that the file is a
139 if((fd
= open(path
, O_RDONLY
)) < 0)
140 fatal(errno
, "error opening %s", path
);
141 if(fstat(fd
, &sb
) < 0)
142 fatal(errno
, "error statting %s", path
);
143 if(!S_ISREG(sb
.st_mode
))
144 fatal(0, "%s: not a regular file", path
);
145 while((n
= read(fd
, buffer
, sizeof buffer
)) > 0) {
146 if(sink_write(output
, buffer
, n
) < 0) {
152 fatal(errno
, "error reading %s", path
);
157 /*$ @include{COMMAND}
159 * Executes COMMAND via the shell (using "sh -c") and copies its
160 * standard output to the template output. The shell command output
161 * is not expanded or modified in any other way.
163 * The shell command's standard error is copied to the error log.
165 * If the shell exits nonzero then this is reported to the error log
166 * but otherwise no special action is taken.
168 static int exp_shell(int attribute((unused
)) nargs
,
171 void attribute((unused
)) *u
) {
177 if(!(pid
= xfork())) {
182 execlp("sh", "sh", "-c", args
[0], (char *)0);
183 fatal(errno
, "error executing sh");
186 while((n
= read(p
[0], buffer
, sizeof buffer
))) {
191 fatal(errno
, "error reading from pipe");
193 if(output
->write(output
, buffer
, n
) < 0)
197 while((n
= waitpid(pid
, &w
, 0)) < 0 && errno
== EINTR
)
200 fatal(errno
, "error calling waitpid");
202 error(0, "shell command '%s' %s", args
[0], wstat(w
));
206 /*$ @if{CONDITION}{IF-TRUE}{IF-FALSE}
208 * If CONDITION is "true" then evaluates to IF-TRUE. Otherwise
209 * evaluates to IF-FALSE. The IF-FALSE part is optional.
211 static int exp_if(int nargs
,
212 const struct mx_node
**args
,
218 if((rc
= mx_expandstr(args
[0], &s
, u
, "argument #0 (CONDITION)")))
221 return mx_expand(args
[1], output
, u
);
223 return mx_expand(args
[2], output
, u
);
228 /*$ @and{BRANCH}{BRANCH}...
230 * Expands to "true" if all the branches are "true" otherwise to "false". If
231 * there are no brances then the result is "true". Only as many branches as
232 * necessary to compute the answer are evaluated (starting from the first one),
233 * so if later branches have side effects they may not take place.
235 static int exp_and(int nargs
,
236 const struct mx_node
**args
,
239 int n
, result
= 1, rc
;
242 for(n
= 0; n
< nargs
; ++n
) {
243 byte_xasprintf(&argname
, "argument #%d", n
);
244 if((rc
= mx_expandstr(args
[n
], &s
, u
, argname
)))
246 if(!mx_str2bool(s
)) {
251 return mx_bool_result(output
, result
);
254 /*$ @or{BRANCH}{BRANCH}...
256 * Expands to "true" if any of the branches are "true" otherwise to "false".
257 * If there are no brances then the result is "false". Only as many branches
258 * as necessary to compute the answer are evaluated (starting from the first
259 * one), so if later branches have side effects they may not take place.
261 static int exp_or(int nargs
,
262 const struct mx_node
**args
,
265 int n
, result
= 0, rc
;
268 for(n
= 0; n
< nargs
; ++n
) {
269 byte_xasprintf(&argname
, "argument #%d", n
);
270 if((rc
= mx_expandstr(args
[n
], &s
, u
, argname
)))
277 return mx_bool_result(output
, result
);
282 * Expands to "true" unless CONDITION is "true" in which case "false".
284 static int exp_not(int attribute((unused
)) nargs
,
287 void attribute((unused
)) *u
) {
288 return mx_bool_result(output
, !mx_str2bool(args
[0]));
293 * Expands to nothing. The argument(s) are not fully evaluated, and no side
296 static int exp_comment(int attribute((unused
)) nargs
,
297 const struct mx_node
attribute((unused
)) **args
,
298 struct sink
attribute((unused
)) *output
,
299 void attribute((unused
)) *u
) {
303 /*$ @urlquote{STRING}
305 * URL-quotes a string, i.e. replaces any characters not safe to use unquoted
306 * in a URL with %-encoded form.
308 static int exp_urlquote(int attribute((unused
)) nargs
,
311 void attribute((unused
)) *u
) {
312 if(sink_writes(output
, urlencodestring(args
[0])) < 0)
320 * Expands to "true" if all the arguments are identical, otherwise to "false"
321 * (i.e. if any pair of arguments differs).
323 * If there are no arguments then expands to "true". Evaluates all arguments
324 * (with their side effects) even if that's not strictly necessary to discover
327 static int exp_eq(int nargs
,
330 void attribute((unused
)) *u
) {
333 for(n
= 1; n
< nargs
; ++n
) {
334 if(strcmp(args
[n
], args
[0])) {
339 return mx_bool_result(output
, result
);
344 * Expands to "true" if all of the arguments differ from one another, otherwise
345 * to "false" (i.e. if any value appears more than once).
347 * If there are no arguments then expands to "true". Evaluates all arguments
348 * (with their side effects) even if that's not strictly necessary to discover
351 static int exp_ne(int nargs
,
354 void attribute((unused
))*u
) {
355 hash
*h
= hash_new(sizeof (char *));
358 for(n
= 0; n
< nargs
; ++n
)
359 if(hash_add(h
, args
[n
], "", HASH_INSERT
)) {
363 return mx_bool_result(output
, result
);
368 * Expands to nothing. Unlike the comment expansion @#{...}, side effects of
369 * arguments are not suppressed. So this can be used to surround a collection
370 * of macro definitions with whitespace, free text commentary, etc.
372 static int exp_discard(int attribute((unused
)) nargs
,
373 char attribute((unused
)) **args
,
374 struct sink
attribute((unused
)) *output
,
375 void attribute((unused
)) *u
) {
379 /*$ @define{NAME}{ARG1 ARG2...}{DEFINITION}
381 * Define a macro. The macro will be called NAME and will act like an
382 * expansion. When it is expanded, the expansion is replaced by DEFINITION,
383 * with each occurence of @ARG1@ etc replaced by the parameters to the
386 static int exp_define(int attribute((unused
)) nargs
,
387 const struct mx_node
**args
,
388 struct sink
attribute((unused
)) *output
,
389 void attribute((unused
)) *u
) {
390 char **as
, *name
, *argnames
;
393 if((rc
= mx_expandstr(args
[0], &name
, u
, "argument #0 (NAME)")))
395 if((rc
= mx_expandstr(args
[1], &argnames
, u
, "argument #1 (ARGS)")))
397 as
= split(argnames
, &nas
, 0, 0, 0);
398 mx_register_macro(name
, nas
, as
, args
[2]);
404 * Expands to the UNQUOTED basename of PATH.
406 static int exp_basename(int attribute((unused
)) nargs
,
408 struct sink
attribute((unused
)) *output
,
409 void attribute((unused
)) *u
) {
410 return sink_writes(output
, d_basename(args
[0])) < 0 ?
-1 : 0;
415 * Expands to the UNQUOTED directory name of PATH.
417 static int exp_dirname(int attribute((unused
)) nargs
,
419 struct sink
attribute((unused
)) *output
,
420 void attribute((unused
)) *u
) {
421 return sink_writes(output
, d_dirname(args
[0])) < 0 ?
-1 : 0;
428 static int exp_q(int attribute((unused
)) nargs
,
430 struct sink
attribute((unused
)) *output
,
431 void attribute((unused
)) *u
) {
432 return sink_writes(output
, args
[0]) < 0 ?
-1 : 0;
435 /** @brief Register built-in expansions */
436 void mx_register_builtin(void) {
437 mx_register("basename", 1, 1, exp_basename
);
438 mx_register("dirname", 1, 1, exp_dirname
);
439 mx_register("discard", 0, INT_MAX
, exp_discard
);
440 mx_register("eq", 0, INT_MAX
, exp_eq
);
441 mx_register("include", 1, 1, exp_include
);
442 mx_register("ne", 0, INT_MAX
, exp_ne
);
443 mx_register("not", 1, 1, exp_not
);
444 mx_register("shell", 1, 1, exp_shell
);
445 mx_register("urlquote", 1, 1, exp_urlquote
);
446 mx_register("q", 1, 1, exp_q
);
447 mx_register_magic("#", 0, INT_MAX
, exp_comment
);
448 mx_register_magic("and", 0, INT_MAX
, exp_and
);
449 mx_register_magic("define", 3, 3, exp_define
);
450 mx_register_magic("if", 2, 3, exp_if
);
451 mx_register_magic("or", 0, INT_MAX
, exp_or
);
454 /** @brief Add a directory to the search path
455 * @param s Directory to add
457 void mx_search_path(const char *s
) {
458 vector_append(&include_path
, xstrdup(s
));