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));