1 /***********************************************************************
2 * *
3 * This software is part of the ast package *
4 * Copyright (c) 1992-2010 AT&T Intellectual Property *
5 * and is licensed under the *
6 * Common Public License, Version 1.0 *
7 * by AT&T Intellectual Property *
8 * *
9 * A copy of the License is available at *
10 * http://www.opensource.org/licenses/cpl1.0.txt *
11 * (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
12 * *
13 * Information and Software Systems Research *
14 * AT&T Research *
15 * Florham Park NJ *
16 * *
17 * Glenn Fowler <gsf@research.att.com> *
18 * David Korn <dgk@research.att.com> *
19 * *
20 ***********************************************************************/
21 #pragma prototyped
22 /*
23 * Glenn Fowler
24 * AT&T Research
25 *
26 * getconf - get configuration values
27 */
28
29 static const char usage[] =
30 "[-?\n@(#)$Id: getconf (AT&T Research) 2008-04-24 $\n]"
31 USAGE_LICENSE
32 "[+NAME?getconf - get configuration values]"
33 "[+DESCRIPTION?\bgetconf\b displays the system configuration value for"
34 " \aname\a. If \aname\a is a filesystem specific variable then"
35 " the value is determined relative to \apath\a or the current"
36 " directory if \apath\a is omitted. If \avalue\a is specified then"
37 " \bgetconf\b attempts to change the process local value to \avalue\a."
38 " \b-\b may be used in place of \apath\a when it is not relevant."
39 " If \apath\a is \b=\b then the the \avalue\a is cached and used"
40 " for subsequent tests in the calling and all child processes."
41 " Only \bwritable\b variables may be set; \breadonly\b variables"
42 " cannot be changed.]"
43 "[+?The current value for \aname\a is written to the standard output. If"
44 " \aname\a is valid but undefined then \bundefined\b is written to"
45 " the standard output. If \aname\a is invalid or an error occurs in"
46 " determining its value, then a diagnostic written to the standard error"
47 " and \bgetconf\b exits with a non-zero exit status.]"
48 "[+?More than one variable may be set or queried by providing the \aname\a"
49 " \apath\a \avalue\a 3-tuple for each variable, specifying \b-\b for"
50 " \avalue\a when querying.]"
51 "[+?If no operands are specified then all known variables are written in"
52 " \aname\a=\avalue\a form to the standard output, one per line."
53 " Only one of \b--call\b, \b--name\b or \b--standard\b may be specified.]"
54 "[+?This implementation uses the \bastgetconf\b(3) string interface to the native"
55 " \bsysconf\b(2), \bconfstr\b(2), \bpathconf\b(2), and \bsysinfo\b(2)"
56 " system calls. If \bgetconf\b on \b$PATH\b is not the default native"
57 " \bgetconf\b, named by \b$(getconf GETCONF)\b, then \bastgetconf\b(3)"
58 " checks only \bast\b specific extensions and the native system calls;"
59 " invalid options and/or names not supported by \bastgetconf\b(3) cause"
60 " the \bgetconf\b on \b$PATH\b to be executed.]"
61
62 "[a:all?Call the native \bgetconf\b(1) with option \b-a\b.]"
63 "[b:base?List base variable name sans call and standard prefixes.]"
64 "[c:call?Display variables with call prefix that matches \aRE\a. The call"
65 " prefixes are:]:[RE]{"
66 " [+CS?\bconfstr\b(2)]"
67 " [+PC?\bpathconf\b(2)]"
68 " [+SC?\bsysconf\b(2)]"
69 " [+SI?\bsysinfo\b(2)]"
70 " [+XX?Constant value.]"
71 "}"
72 "[d:defined?Only display defined values when no operands are specified.]"
73 "[l:lowercase?List variable names in lower case.]"
74 "[n:name?Display variables with name that match \aRE\a.]:[RE]"
75 "[p:portable?Display the named \bwritable\b variables and values in a form that"
76 " can be directly executed by \bsh\b(1) to set the values. If \aname\a"
77 " is omitted then all \bwritable\b variables are listed.]"
78 "[q:quote?\"...\" quote values.]"
79 "[r:readonly?Display the named \breadonly\b variables in \aname\a=\avalue\a form."
80 " If \aname\a is omitted then all \breadonly\b variables are listed.]"
81 "[s:standard?Display variables with standard prefix that matches \aRE\a."
82 " Use the \b--table\b option to view all standard prefixes, including"
83 " local additions. The standard prefixes available on all systems"
84 " are:]:[RE]{"
85 " [+AES]"
86 " [+AST]"
87 " [+C]"
88 " [+GNU]"
89 " [+POSIX]"
90 " [+SVID]"
91 " [+XBS5]"
92 " [+XOPEN]"
93 " [+XPG]"
94 "}"
95 "[t:table?Display the internal table that contains the name, standard,"
96 " standard section, and system call symbol prefix for each variable.]"
97 "[w:writable?Display the named \bwritable\b variables in \aname\a=\avalue\a"
98 " form. If \aname\a is omitted then all \bwritable\b variables are"
99 " listed.]"
100 "[v:specification?Call the native \bgetconf\b(1) with option"
101 " \b-v\b \aname\a.]:[name]"
102
103 "\n"
104 "\n[ name [ path [ value ] ] ... ]\n"
105 "\n"
106
107 "[+ENVIRONMENT]{"
108 " [+_AST_FEATURES?Process local writable values that are different from"
109 " the default are stored in the \b_AST_FEATURES\b environment"
110 " variable. The \b_AST_FEATURES\b value is a space-separated"
111 " list of \aname\a \apath\a \avalue\a 3-tuples, where"
112 " \aname\a is the system configuration name, \apath\a is the"
113 " corresponding path, \b-\b if no path is applicable, and"
114 " \avalue\a is the system configuration value.]"
115 "}"
116 "[+SEE ALSO?\bpathchk\b(1), \bconfstr\b(2), \bpathconf\b(2),"
117 " \bsysconf\b(2), \bastgetconf\b(3)]"
118 ;
119
120 #include <cmd.h>
121 #include <proc.h>
122 #include <ls.h>
123
124 typedef struct Path_s
125 {
126 const char* path;
127 int len;
128 } Path_t;
129
130 int
b_getconf(int argc,char ** argv,void * context)131 b_getconf(int argc, char** argv, void* context)
132 {
133 register char* name;
134 register char* path;
135 register char* value;
136 register const char* s;
137 register const char* t;
138 char* pattern;
139 char* native;
140 char* cmd;
141 Path_t* e;
142 Path_t* p;
143 int flags;
144 int n;
145 int i;
146 int m;
147 int q;
148 char** oargv;
149 char buf[PATH_MAX];
150 Path_t std[64];
151 struct stat st0;
152 struct stat st1;
153
154 static const char empty[] = "-";
155 static const Path_t equiv[] = { { "/bin", 4 }, { "/usr/bin", 8 } };
156
157 cmdinit(argc, argv, context, ERROR_CATALOG, 0);
158 oargv = argv;
159 if (*(native = astconf("GETCONF", NiL, NiL)) != '/')
160 native = 0;
161 flags = 0;
162 name = 0;
163 pattern = 0;
164 for (;;)
165 {
166 switch (optget(argv, usage))
167 {
168 case 'a':
169 if (native)
170 goto defer;
171 continue;
172 case 'b':
173 flags |= ASTCONF_base;
174 continue;
175 case 'c':
176 flags |= ASTCONF_matchcall;
177 pattern = opt_info.arg;
178 continue;
179 case 'd':
180 flags |= ASTCONF_defined;
181 continue;
182 case 'l':
183 flags |= ASTCONF_lower;
184 continue;
185 case 'n':
186 flags |= ASTCONF_matchname;
187 pattern = opt_info.arg;
188 continue;
189 case 'p':
190 flags |= ASTCONF_parse;
191 continue;
192 case 'q':
193 flags |= ASTCONF_quote;
194 continue;
195 case 'r':
196 flags |= ASTCONF_read;
197 continue;
198 case 's':
199 flags |= ASTCONF_matchstandard;
200 pattern = opt_info.arg;
201 continue;
202 case 't':
203 flags |= ASTCONF_table;
204 continue;
205 case 'v':
206 if (native)
207 goto defer;
208 continue;
209 case 'w':
210 flags |= ASTCONF_write;
211 continue;
212 case ':':
213 if (native)
214 goto defer;
215 error(2, "%s", opt_info.arg);
216 break;
217 case '?':
218 error(ERROR_usage(2), "%s", opt_info.arg);
219 break;
220 }
221 break;
222 }
223 argv += opt_info.index;
224 if (!(name = *argv))
225 path = 0;
226 else if (streq(name, empty))
227 {
228 name = 0;
229 if (path = *++argv)
230 {
231 argv++;
232 if (streq(path, empty))
233 path = 0;
234 }
235 }
236 if (error_info.errors || !name && *argv)
237 error(ERROR_usage(2), "%s", optusage(NiL));
238 if (!name)
239 astconflist(sfstdout, path, flags, pattern);
240 else
241 {
242 flags = native ? (ASTCONF_system|ASTCONF_error) : 0;
243 do
244 {
245 if (!(path = *++argv))
246 value = 0;
247 else
248 {
249 if (streq(path, empty))
250 {
251 path = 0;
252 flags = 0;
253 }
254 if ((value = *++argv) && (streq(value, empty)))
255 {
256 value = 0;
257 flags = 0;
258 }
259 }
260 s = astgetconf(name, path, value, flags, errorf);
261 if (error_info.errors)
262 break;
263 if (!s)
264 goto defer;
265 if (!value)
266 {
267 if (flags & ASTCONF_write)
268 {
269 sfputr(sfstdout, name, ' ');
270 sfputr(sfstdout, path ? path : empty, ' ');
271 }
272 sfputr(sfstdout, s, '\n');
273 }
274 } while (*argv && (name = *++argv));
275 }
276 return error_info.errors != 0;
277
278 defer:
279
280 /*
281 * defer to argv[0] if absolute and it exists
282 */
283
284 if ((cmd = oargv[0]) && *cmd == '/' && !access(cmd, X_OK))
285 goto found;
286
287 /*
288 * defer to the first getconf on $PATH that is also on the standard PATH
289 */
290
291 e = std;
292 s = astconf("PATH", NiL, NiL);
293 q = !stat(equiv[0].path, &st0) && !stat(equiv[1].path, &st1) && st0.st_ino == st1.st_ino && st0.st_dev == st1.st_dev;
294 m = 0;
295 do
296 {
297 for (t = s; *s && *s != ':'; s++);
298 if ((n = s - t) && *t == '/')
299 {
300 if (q)
301 for (i = 0; i < 2; i++)
302 if (n == equiv[i].len && !strncmp(t, equiv[i].path, n))
303 {
304 if (m & (i+1))
305 t = 0;
306 else
307 {
308 m |= (i+1);
309 if (!(m & (!i+1)))
310 {
311 m |= (!i+1);
312 e->path = t;
313 e->len = n;
314 e++;
315 if (e >= &std[elementsof(std)])
316 break;
317 t = equiv[!i].path;
318 n = equiv[!i].len;
319 }
320 }
321 }
322 if (t)
323 {
324 e->path = t;
325 e->len = n;
326 e++;
327 }
328 }
329 while (*s == ':')
330 s++;
331 } while (*s && e < &std[elementsof(std)]);
332 if (e < &std[elementsof(std)])
333 {
334 e->len = strlen(e->path = "/usr/sbin");
335 if (++e < &std[elementsof(std)])
336 {
337 e->len = strlen(e->path = "/sbin");
338 e++;
339 }
340 }
341 if (s = getenv("PATH"))
342 do
343 {
344 for (t = s; *s && *s != ':'; s++);
345 if ((n = s - t) && *t == '/')
346 {
347 for (p = std; p < e; p++)
348 if (p->len == n && !strncmp(t, p->path, n))
349 {
350 sfsprintf(buf, sizeof(buf), "%-*.*s/%s", n, n, t, error_info.id);
351 if (!access(buf, X_OK))
352 {
353 cmd = buf;
354 goto found;
355 }
356 }
357 }
358 while (*s == ':')
359 s++;
360 } while (*s);
361
362 /*
363 * defer to the first getconf on the standard PATH
364 */
365
366 for (p = std; p < e; p++)
367 {
368 sfsprintf(buf, sizeof(buf), "%-*.*s/%s", p->len, p->len, p->path, error_info.id);
369 if (!access(buf, X_OK))
370 {
371 cmd = buf;
372 goto found;
373 }
374 }
375
376 /*
377 * out of deferrals
378 */
379
380 if (name)
381 error(4, "%s: unknown name -- no native getconf(1) to defer to", name);
382 else
383 error(4, "no native getconf(1) to defer to");
384 return 2;
385
386 found:
387
388 /*
389 * don't blame us for crappy diagnostics
390 */
391
392 oargv[0] = cmd;
393 if ((n = sh_run(context, argc, oargv)) >= EXIT_NOEXEC)
394 error(ERROR_SYSTEM|2, "%s: exec error [%d]", cmd, n);
395 return n;
396 }
397