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Merge mac build fix
[disorder] / lib / macros-builtin.c
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1/*
2 * This file is part of DisOrder
3 * Copyright (C) 2008 Richard Kettlewell
4 *
e7eb3a27 5 * This program is free software: you can redistribute it and/or modify
f640bcb3 6 * it under the terms of the GNU General Public License as published by
e7eb3a27 7 * the Free Software Foundation, either version 3 of the License, or
f640bcb3 8 * (at your option) any later version.
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9 *
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.
14 *
f640bcb3 15 * You should have received a copy of the GNU General Public License
e7eb3a27 16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
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17 */
18
19/** @file lib/macros-builtin.c
20 * @brief Built-in expansions
21 *
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22 * This is a grab-bag of non-domain-specific expansions
23 *
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.
27 *
28 * To make a bulleted list, put a '-' at the start of each line.
29 *
30 * You can currently get away with troff markup but this is horribly ugly and
31 * might be changed.
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32 */
33
05b75f8d 34#include "common.h"
f640bcb3 35
f640bcb3 36#include <errno.h>
f640bcb3 37#include <unistd.h>
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38#include <fcntl.h>
39#include <sys/stat.h>
f640bcb3 40
9faa7a88 41#include "hash.h"
b36be3a1 42#include "mem.h"
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43#include "macros.h"
44#include "sink.h"
45#include "syscalls.h"
46#include "log.h"
47#include "wstat.h"
48#include "kvp.h"
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49#include "split.h"
50#include "printf.h"
51#include "vector.h"
2257512d 52#include "filepart.h"
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53
54static struct vector include_path;
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55
56/** @brief Return 1 if @p s is 'true' else 0 */
57int mx_str2bool(const char *s) {
58 return !strcmp(s, "true");
59}
60
61/** @brief Return "true" if @p n is nonzero else "false" */
62const char *mx_bool2str(int n) {
63 return n ? "true" : "false";
64}
65
b36be3a1 66/** @brief Write a boolean result */
71634563 67int mx_bool_result(struct sink *output, int result) {
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68 if(sink_writes(output, mx_bool2str(result)) < 0)
69 return -1;
70 else
71 return 0;
72}
73
9faa7a88 74/** @brief Search the include path */
f2d306b4 75char *mx_find(const char *name, int report) {
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76 char *path;
77 int n;
78
79 if(name[0] == '/') {
80 if(access(name, O_RDONLY) < 0) {
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81 if(report)
82 error(errno, "cannot read %s", name);
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83 return 0;
84 }
85 path = xstrdup(name);
86 } else {
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)
91 break;
92 }
93 if(n >= include_path.nvec) {
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94 if(report)
95 error(0, "cannot find '%s' in search path", name);
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96 return 0;
97 }
98 }
99 return path;
100}
101
2dc2f478 102/*$ @include{TEMPLATE}
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103 *
104 * Includes TEMPLATE.
105 *
106 * TEMPLATE can be an absolute filename starting with a '/'; only the file with
107 * exactly this name will be included.
108 *
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).
f640bcb3 113 *
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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
116 * modification.
117 *
118 * Only regular files are allowed (no devices, sockets or name pipes).
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119 */
120static int exp_include(int attribute((unused)) nargs,
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121 char **args,
122 struct sink *output,
123 void *u) {
9faa7a88 124 const char *path;
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125 int fd, n;
126 char buffer[4096];
127 struct stat sb;
b36be3a1 128
f2d306b4 129 if(!(path = mx_find(args[0], 1/*report*/))) {
f5fdc06f 130 if(sink_printf(output, "[[cannot find '%s']]", args[0]) < 0)
dd0f422a 131 return 0;
9faa7a88 132 return 0;
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133 }
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
138 * regular file. */
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) {
147 xclose(fd);
148 return -1;
149 }
150 }
151 if(n < 0)
152 fatal(errno, "error reading %s", path);
153 xclose(fd);
154 return 0;
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155}
156
2dc2f478 157/*$ @include{COMMAND}
f640bcb3 158 *
32a6d08f 159 * Executes COMMAND via the shell (using "sh \-c") and copies its
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160 * standard output to the template output. The shell command output
161 * is not expanded or modified in any other way.
162 *
163 * The shell command's standard error is copied to the error log.
164 *
165 * If the shell exits nonzero then this is reported to the error log
166 * but otherwise no special action is taken.
167 */
168static int exp_shell(int attribute((unused)) nargs,
169 char **args,
170 struct sink *output,
171 void attribute((unused)) *u) {
172 int w, p[2], n;
173 char buffer[4096];
174 pid_t pid;
175
176 xpipe(p);
177 if(!(pid = xfork())) {
178 exitfn = _exit;
179 xclose(p[0]);
180 xdup2(p[1], 1);
181 xclose(p[1]);
182 execlp("sh", "sh", "-c", args[0], (char *)0);
183 fatal(errno, "error executing sh");
184 }
185 xclose(p[1]);
186 while((n = read(p[0], buffer, sizeof buffer))) {
187 if(n < 0) {
188 if(errno == EINTR)
189 continue;
190 else
191 fatal(errno, "error reading from pipe");
192 }
193 if(output->write(output, buffer, n) < 0)
194 return -1;
195 }
196 xclose(p[0]);
197 while((n = waitpid(pid, &w, 0)) < 0 && errno == EINTR)
198 ;
199 if(n < 0)
200 fatal(errno, "error calling waitpid");
201 if(w)
202 error(0, "shell command '%s' %s", args[0], wstat(w));
203 return 0;
204}
205
2dc2f478 206/*$ @if{CONDITION}{IF-TRUE}{IF-FALSE}
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207 *
208 * If CONDITION is "true" then evaluates to IF-TRUE. Otherwise
209 * evaluates to IF-FALSE. The IF-FALSE part is optional.
210 */
211static int exp_if(int nargs,
212 const struct mx_node **args,
213 struct sink *output,
214 void *u) {
215 char *s;
216 int rc;
217
b36be3a1 218 if((rc = mx_expandstr(args[0], &s, u, "argument #0 (CONDITION)")))
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219 return rc;
220 if(mx_str2bool(s))
221 return mx_expand(args[1], output, u);
222 else if(nargs > 2)
223 return mx_expand(args[2], output, u);
224 else
225 return 0;
226}
227
2dc2f478 228/*$ @and{BRANCH}{BRANCH}...
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229 *
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.
234 */
235static int exp_and(int nargs,
236 const struct mx_node **args,
237 struct sink *output,
238 void *u) {
239 int n, result = 1, rc;
b36be3a1 240 char *s, *argname;
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241
242 for(n = 0; n < nargs; ++n) {
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243 byte_xasprintf(&argname, "argument #%d", n);
244 if((rc = mx_expandstr(args[n], &s, u, argname)))
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245 return rc;
246 if(!mx_str2bool(s)) {
247 result = 0;
248 break;
249 }
250 }
b36be3a1 251 return mx_bool_result(output, result);
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252}
253
2dc2f478 254/*$ @or{BRANCH}{BRANCH}...
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255 *
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.
260 */
261static int exp_or(int nargs,
262 const struct mx_node **args,
263 struct sink *output,
264 void *u) {
265 int n, result = 0, rc;
b36be3a1 266 char *s, *argname;
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267
268 for(n = 0; n < nargs; ++n) {
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269 byte_xasprintf(&argname, "argument #%d", n);
270 if((rc = mx_expandstr(args[n], &s, u, argname)))
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271 return rc;
272 if(mx_str2bool(s)) {
273 result = 1;
274 break;
275 }
276 }
b36be3a1 277 return mx_bool_result(output, result);
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278}
279
2dc2f478 280/*$ @not{CONDITION}
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281 *
282 * Expands to "true" unless CONDITION is "true" in which case "false".
283 */
284static int exp_not(int attribute((unused)) nargs,
285 char **args,
286 struct sink *output,
287 void attribute((unused)) *u) {
b36be3a1 288 return mx_bool_result(output, !mx_str2bool(args[0]));
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289}
290
2dc2f478 291/*$ @#{...}
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292 *
293 * Expands to nothing. The argument(s) are not fully evaluated, and no side
294 * effects occur.
295 */
296static 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) {
300 return 0;
301}
302
2dc2f478 303/*$ @urlquote{STRING}
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304 *
305 * URL-quotes a string, i.e. replaces any characters not safe to use unquoted
306 * in a URL with %-encoded form.
307 */
308static int exp_urlquote(int attribute((unused)) nargs,
309 char **args,
310 struct sink *output,
311 void attribute((unused)) *u) {
312 if(sink_writes(output, urlencodestring(args[0])) < 0)
313 return -1;
314 else
315 return 0;
316}
317
2dc2f478 318/*$ @eq{S1}{S2}...
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319 *
320 * Expands to "true" if all the arguments are identical, otherwise to "false"
321 * (i.e. if any pair of arguments differs).
322 *
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
325 * the result.
326 */
327static int exp_eq(int nargs,
328 char **args,
329 struct sink *output,
330 void attribute((unused)) *u) {
331 int n, result = 1;
332
333 for(n = 1; n < nargs; ++n) {
334 if(strcmp(args[n], args[0])) {
335 result = 0;
336 break;
337 }
338 }
339 return mx_bool_result(output, result);
340}
341
2dc2f478 342/*$ @ne{S1}{S2}...
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343 *
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).
346 *
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
349 * the result.
350 */
351static int exp_ne(int nargs,
352 char **args,
353 struct sink *output,
354 void attribute((unused))*u) {
355 hash *h = hash_new(sizeof (char *));
356 int n, result = 1;
357
358 for(n = 0; n < nargs; ++n)
359 if(hash_add(h, args[n], "", HASH_INSERT)) {
360 result = 0;
361 break;
362 }
363 return mx_bool_result(output, result);
364}
365
2dc2f478 366/*$ @discard{...}
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367 *
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.
371 */
372static int exp_discard(int attribute((unused)) nargs,
373 char attribute((unused)) **args,
374 struct sink attribute((unused)) *output,
375 void attribute((unused)) *u) {
376 return 0;
377}
378
2dc2f478 379/*$ @define{NAME}{ARG1 ARG2...}{DEFINITION}
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380 *
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
384 * expansion.
385 */
386static 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;
391 int rc, nas;
392
393 if((rc = mx_expandstr(args[0], &name, u, "argument #0 (NAME)")))
394 return rc;
395 if((rc = mx_expandstr(args[1], &argnames, u, "argument #1 (ARGS)")))
396 return rc;
397 as = split(argnames, &nas, 0, 0, 0);
398 mx_register_macro(name, nas, as, args[2]);
399 return 0;
400}
401
59cf25c4 402/*$ @basename{PATH}
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403 *
404 * Expands to the UNQUOTED basename of PATH.
405 */
406static int exp_basename(int attribute((unused)) nargs,
407 char **args,
408 struct sink attribute((unused)) *output,
409 void attribute((unused)) *u) {
410 return sink_writes(output, d_basename(args[0])) < 0 ? -1 : 0;
411}
412
59cf25c4 413/*$ @dirname{PATH}
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414 *
415 * Expands to the UNQUOTED directory name of PATH.
416 */
417static int exp_dirname(int attribute((unused)) nargs,
418 char **args,
419 struct sink attribute((unused)) *output,
420 void attribute((unused)) *u) {
421 return sink_writes(output, d_dirname(args[0])) < 0 ? -1 : 0;
422}
423
59cf25c4 424/*$ @q{STRING}
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425 *
426 * Expands to STRING.
427 */
428static int exp_q(int attribute((unused)) nargs,
429 char **args,
430 struct sink attribute((unused)) *output,
431 void attribute((unused)) *u) {
432 return sink_writes(output, args[0]) < 0 ? -1 : 0;
433}
434
dd0f422a 435/** @brief Register built-in expansions */
f640bcb3 436void mx_register_builtin(void) {
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437 mx_register("basename", 1, 1, exp_basename);
438 mx_register("dirname", 1, 1, exp_dirname);
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439 mx_register("discard", 0, INT_MAX, exp_discard);
440 mx_register("eq", 0, INT_MAX, exp_eq);
f640bcb3 441 mx_register("include", 1, 1, exp_include);
b36be3a1 442 mx_register("ne", 0, INT_MAX, exp_ne);
f640bcb3 443 mx_register("not", 1, 1, exp_not);
b36be3a1 444 mx_register("shell", 1, 1, exp_shell);
f640bcb3 445 mx_register("urlquote", 1, 1, exp_urlquote);
721d8bf4 446 mx_register("q", 1, 1, exp_q);
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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);
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452}
453
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454/** @brief Add a directory to the search path
455 * @param s Directory to add
456 */
457void mx_search_path(const char *s) {
458 vector_append(&include_path, xstrdup(s));
459}
460
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461/*
462Local Variables:
463c-basic-offset:2
464comment-column:40
465fill-column:79
466indent-tabs-mode:nil
467End:
468*/