xref: /netbsd-src/external/bsd/ntp/dist/sntp/libopts/load.c (revision 7bdf38e5b7a28439665f2fdeff81e36913eef7dd)
1 /*	$NetBSD: load.c,v 1.10 2024/08/18 20:47:24 christos Exp $	*/
2 
3 
4 /**
5  *  \file load.c
6  *
7  *  This file contains the routines that deal with processing text strings
8  *  for options, either from a NUL-terminated string passed in or from an
9  *  rc/ini file.
10  *
11  * @addtogroup autoopts
12  * @{
13  */
14 /*
15  *  This file is part of AutoOpts, a companion to AutoGen.
16  *  AutoOpts is free software.
17  *  AutoOpts is Copyright (C) 1992-2018 by Bruce Korb - all rights reserved
18  *
19  *  AutoOpts is available under any one of two licenses.  The license
20  *  in use must be one of these two and the choice is under the control
21  *  of the user of the license.
22  *
23  *   The GNU Lesser General Public License, version 3 or later
24  *      See the files "COPYING.lgplv3" and "COPYING.gplv3"
25  *
26  *   The Modified Berkeley Software Distribution License
27  *      See the file "COPYING.mbsd"
28  *
29  *  These files have the following sha256 sums:
30  *
31  *  8584710e9b04216a394078dc156b781d0b47e1729104d666658aecef8ee32e95  COPYING.gplv3
32  *  4379e7444a0e2ce2b12dd6f5a52a27a4d02d39d247901d3285c88cf0d37f477b  COPYING.lgplv3
33  *  13aa749a5b0a454917a944ed8fffc530b784f5ead522b1aacaf4ec8aa55a6239  COPYING.mbsd
34  */
35 
36 static bool
37 get_realpath(char * buf, size_t b_sz)
38 {
39 #if defined(HAVE_CANONICALIZE_FILE_NAME)
40     {
41         size_t name_len;
42 
43         char * pz = canonicalize_file_name(buf);
44         if (pz == NULL)
45             return false;
46 
47         name_len = strlen(pz);
48         if (name_len >= (size_t)b_sz) {
49             free(pz);
50             return false;
51         }
52 
53         memcpy(buf, pz, name_len + 1);
54         free(pz);
55     }
56 
57 #elif defined(HAVE_REALPATH)
58     {
59         size_t name_len;
60         char z[PATH_MAX+1];
61 
62         if (realpath(buf, z) == NULL)
63             return false;
64 
65         name_len = strlen(z);
66         if (name_len >= b_sz)
67             return false;
68 
69         memcpy(buf, z, name_len + 1);
70     }
71 #endif
72     return true;
73 }
74 
75 /*=export_func  optionMakePath
76  * private:
77  *
78  * what:  translate and construct a path
79  * arg:   + char *       + p_buf     + The result buffer +
80  * arg:   + int          + b_sz      + The size of this buffer +
81  * arg:   + char const * + fname     + The input name +
82  * arg:   + char const * + prg_path  + The full path of the current program +
83  *
84  * ret-type: bool
85  * ret-desc: true if the name was handled, otherwise false.
86  *           If the name does not start with ``$'', then it is handled
87  *           simply by copying the input name to the output buffer and
88  *           resolving the name with either
89  *           @code{canonicalize_file_name(3GLIBC)} or @code{realpath(3C)}.
90  *
91  * doc:
92  *
93  *  This routine will copy the @code{pzName} input name into the
94  *  @code{pzBuf} output buffer, not exceeding @code{bufSize} bytes.  If the
95  *  first character of the input name is a @code{'$'} character, then there
96  *  is special handling:
97  *  @*
98  *  @code{$$} is replaced with the directory name of the @code{pzProgPath},
99  *  searching @code{$PATH} if necessary.
100  *  @*
101  *  @code{$@} is replaced with the AutoGen package data installation directory
102  *  (aka @code{pkgdatadir}).
103  *  @*
104  *  @code{$NAME} is replaced by the contents of the @code{NAME} environment
105  *  variable.  If not found, the search fails.
106  *
107  *  Please note: both @code{$$} and @code{$NAME} must be at the start of the
108  *     @code{pzName} string and must either be the entire string or be followed
109  *     by the @code{'/'} (backslash on windows) character.
110  *
111  * err:  @code{false} is returned if:
112  *       @*
113  *       @bullet{} The input name exceeds @code{bufSize} bytes.
114  *       @*
115  *       @bullet{} @code{$$}, @code{$@@} or @code{$NAME} is not the full string
116  *                 and the next character is not '/'.
117  *       @*
118  *       @bullet{} libopts was built without PKGDATADIR defined and @code{$@@}
119  *                 was specified.
120  *       @*
121  *       @bullet{} @code{NAME} is not a known environment variable
122  *       @*
123  *       @bullet{} @code{canonicalize_file_name} or @code{realpath} return
124  *                 errors (cannot resolve the resulting path).
125 =*/
126 bool
127 optionMakePath(char * p_buf, int b_sz, char const * fname, char const * prg_path)
128 {
129     {
130         size_t len = strlen(fname);
131 
132         if (((size_t)b_sz <= len) || (len == 0))
133             return false;
134     }
135 
136     /*
137      *  IF not an environment variable, just copy the data
138      */
139     if (*fname != '$') {
140         char   const * src = fname;
141         char * dst = p_buf;
142         int    ct  = b_sz;
143 
144         for (;;) {
145             if ( (*(dst++) = *(src++)) == NUL)
146                 break;
147             if (--ct <= 0)
148                 return false;
149         }
150     }
151 
152     /*
153      *  IF the name starts with "$$", then it must be "$$" or
154      *  it must start with "$$/".  In either event, replace the "$$"
155      *  with the path to the executable and append a "/" character.
156      */
157     else switch (fname[1]) {
158     case NUL:
159         return false;
160 
161     case '$':
162         if (! add_prog_path(p_buf, b_sz, fname, prg_path))
163             return false;
164         break;
165 
166     case '@':
167         if (program_pkgdatadir[0] == NUL)
168             return false;
169 
170         if (snprintf(p_buf, (size_t)b_sz, "%s%s",
171                      program_pkgdatadir, fname + 2) >= b_sz)
172             return false;
173         break;
174 
175     default:
176         if (! add_env_val(p_buf, b_sz, fname))
177             return false;
178     }
179 
180     return get_realpath(p_buf, b_sz);
181 }
182 
183 /**
184  * convert a leading "$$" into a path to the executable.
185  */
186 static bool
187 add_prog_path(char * buf, int b_sz, char const * fname, char const * prg_path)
188 {
189     char const *   path;
190     char const *   pz;
191     int     skip = 2;
192     size_t  fname_len;
193     size_t  dir_len;  //!< length of the directory portion of the path to the exe
194 
195     switch (fname[2]) {
196     case DIRCH:
197         skip = 3;
198     case NUL:
199         break;
200     default:
201         return false;
202     }
203 
204     /*
205      *  See if the path is included in the program name.
206      *  If it is, we're done.  Otherwise, we have to hunt
207      *  for the program using "pathfind".
208      */
209     if (strchr(prg_path, DIRCH) != NULL)
210         path = prg_path;
211     else {
212         path = pathfind(getenv("PATH"), prg_path, "rx");
213 
214         if (path == NULL)
215             return false;
216     }
217 
218     pz = strrchr(path, DIRCH);
219 
220     /*
221      *  IF we cannot find a directory name separator,
222      *  THEN we do not have a path name to our executable file.
223      */
224     if (pz == NULL)
225         return false;
226 
227     fname    += skip;
228     fname_len = strlen(fname) + 1; // + NUL byte
229     dir_len   = (pz - path) + 1;   // + dir sep character
230 
231     /*
232      *  Concatenate the file name to the end of the executable path.
233      *  The result may be either a file or a directory.
234      */
235     if (dir_len + fname_len > (unsigned)b_sz)
236         return false;
237 
238     memcpy(buf, path, dir_len);
239     memcpy(buf + dir_len, fname, fname_len);
240 
241     /*
242      *  If the "path" path was gotten from "pathfind()", then it was
243      *  allocated and we need to deallocate it.
244      */
245     if (path != prg_path)
246         AGFREE(path);
247     return true;
248 }
249 
250 /**
251  * Add an environment variable value.
252  */
253 static bool
254 add_env_val(char * buf, int buf_sz, char const * name)
255 {
256     char * dir_part = buf;
257 
258     for (;;) {
259         int ch = (int)*++name;
260         if (! IS_VALUE_NAME_CHAR(ch))
261             break;
262         *(dir_part++) = (char)ch;
263     }
264 
265     if (dir_part == buf)
266         return false;
267 
268     *dir_part = NUL;
269 
270     dir_part = getenv(buf);
271 
272     /*
273      *  Environment value not found -- skip the home list entry
274      */
275     if (dir_part == NULL)
276         return false;
277 
278     {
279         size_t dir_len = strlen(dir_part);
280         size_t nm_len  = strlen(name) + 1;
281 
282         if (dir_len + nm_len >= (unsigned)buf_sz)
283             return false;
284         memcpy(buf, dir_part, dir_len);
285         memcpy(buf + dir_len, name, nm_len);
286     }
287 
288     return true;
289 }
290 
291 /**
292  * Trim leading and trailing white space.
293  * If we are cooking the text and the text is quoted, then "cook"
294  * the string.  To cook, the string must be quoted.
295  *
296  * @param[in,out] txt  the input and output string
297  * @param[in]     mode the handling mode (cooking method)
298  */
299 static void
300 munge_str(char * txt, tOptionLoadMode mode)
301 {
302     char * end;
303 
304     if (mode == OPTION_LOAD_KEEP)
305         return;
306 
307     if (IS_WHITESPACE_CHAR(*txt)) {
308         char * src = SPN_WHITESPACE_CHARS(txt+1);
309         size_t l   = strlen(src) + 1;
310         memmove(txt, src, l);
311         end = txt + l - 1;
312 
313     } else
314         end = txt + strlen(txt);
315 
316     end  = SPN_WHITESPACE_BACK(txt, end);
317     *end = NUL;
318 
319     if (mode == OPTION_LOAD_UNCOOKED)
320         return;
321 
322     switch (*txt) {
323     default: return;
324     case '"':
325     case '\'': break;
326     }
327 
328     switch (end[-1]) {
329     default: return;
330     case '"':
331     case '\'': break;
332     }
333 
334     (void)ao_string_cook(txt, NULL);
335 }
336 
337 static char *
338 assemble_arg_val(char * txt, tOptionLoadMode mode)
339 {
340     char * end = strpbrk(txt, ARG_BREAK_STR);
341     int    space_break;
342 
343     /*
344      *  Not having an argument to a configurable name is okay.
345      */
346     if (end == NULL)
347         return txt + strlen(txt);
348 
349     /*
350      *  If we are keeping all whitespace, then the  modevalue starts with the
351      *  character that follows the end of the configurable name, regardless
352      *  of which character caused it.
353      */
354     if (mode == OPTION_LOAD_KEEP) {
355         *(end++) = NUL;
356         return end;
357     }
358 
359     /*
360      *  If the name ended on a white space character, remember that
361      *  because we'll have to skip over an immediately following ':' or '='
362      *  (and the white space following *that*).
363      */
364     space_break = IS_WHITESPACE_CHAR(*end);
365     *(end++) = NUL;
366 
367     end = SPN_WHITESPACE_CHARS(end);
368     if (space_break && ((*end == ':') || (*end == '=')))
369         end = SPN_WHITESPACE_CHARS(end+1);
370 
371     return end;
372 }
373 
374 static char *
375 trim_quotes(char * arg)
376 {
377     switch (*arg) {
378     case '"':
379     case '\'':
380         ao_string_cook(arg, NULL);
381     }
382     return arg;
383 }
384 
385 /**
386  * See if the option is to be processed in the current scan direction
387  * (-1 or +1).
388  */
389 static bool
390 direction_ok(opt_state_mask_t f, int dir)
391 {
392     if (dir == 0)
393         return true;
394 
395     switch (f & (OPTST_IMM|OPTST_DISABLE_IMM)) {
396     case 0:
397         /*
398          *  The selected option has no immediate action.
399          *  THEREFORE, if the direction is PRESETTING
400          *  THEN we skip this option.
401          */
402         if (PRESETTING(dir))
403             return false;
404         break;
405 
406     case OPTST_IMM:
407         if (PRESETTING(dir)) {
408             /*
409              *  We are in the presetting direction with an option we handle
410              *  immediately for enablement, but normally for disablement.
411              *  Therefore, skip if disabled.
412              */
413             if ((f & OPTST_DISABLED) == 0)
414                 return false;
415         } else {
416             /*
417              *  We are in the processing direction with an option we handle
418              *  immediately for enablement, but normally for disablement.
419              *  Therefore, skip if NOT disabled.
420              */
421             if ((f & OPTST_DISABLED) != 0)
422                 return false;
423         }
424         break;
425 
426     case OPTST_DISABLE_IMM:
427         if (PRESETTING(dir)) {
428             /*
429              *  We are in the presetting direction with an option we handle
430              *  immediately for disablement, but normally for handling.
431              *  Therefore, skip if NOT disabled.
432              */
433             if ((f & OPTST_DISABLED) != 0)
434                 return false;
435         } else {
436             /*
437              *  We are in the processing direction with an option we handle
438              *  immediately for disablement, but normally for handling.
439              *  Therefore, skip if disabled.
440              */
441             if ((f & OPTST_DISABLED) == 0)
442                 return false;
443         }
444         break;
445 
446     case OPTST_IMM|OPTST_DISABLE_IMM:
447         /*
448          *  The selected option is always for immediate action.
449          *  THEREFORE, if the direction is PROCESSING
450          *  THEN we skip this option.
451          */
452         if (PROCESSING(dir))
453             return false;
454         break;
455     }
456     return true;
457 }
458 
459 /**
460  *  Load an option from a block of text.  The text must start with the
461  *  configurable/option name and be followed by its associated value.
462  *  That value may be processed in any of several ways.  See "tOptionLoadMode"
463  *  in autoopts.h.
464  *
465  * @param[in,out] opts       program options descriptor
466  * @param[in,out] opt_state  option processing state
467  * @param[in,out] line       source line with long option name in it
468  * @param[in]     direction  current processing direction (preset or not)
469  * @param[in]     load_mode  option loading mode (OPTION_LOAD_*)
470  */
471 static void
472 load_opt_line(tOptions * opts, tOptState * opt_state, char * line,
473               tDirection direction, tOptionLoadMode load_mode )
474 {
475     /*
476      * When parsing a stored line, we only look at the characters after
477      * a hyphen.  Long names must always be at least two characters and
478      * short options are always exactly one character long.
479      */
480     line = SPN_LOAD_LINE_SKIP_CHARS(line);
481 
482     {
483         char * arg = assemble_arg_val(line, load_mode);
484 
485         if (IS_OPTION_NAME_CHAR(line[1])) {
486 
487             if (! SUCCESSFUL(opt_find_long(opts, line, opt_state)))
488                 return;
489 
490         } else if (! SUCCESSFUL(opt_find_short(opts, *line, opt_state)))
491             return;
492 
493         if ((! CALLED(direction)) && (opt_state->flags & OPTST_NO_INIT))
494             return;
495 
496         opt_state->pzOptArg = trim_quotes(arg);
497     }
498 
499     if (! direction_ok(opt_state->flags, direction))
500         return;
501 
502     /*
503      *  Fix up the args.
504      */
505     if (OPTST_GET_ARGTYPE(opt_state->pOD->fOptState) == OPARG_TYPE_NONE) {
506         if (*opt_state->pzOptArg != NUL)
507             return;
508         opt_state->pzOptArg = NULL;
509 
510     } else if (opt_state->pOD->fOptState & OPTST_ARG_OPTIONAL) {
511         if (*opt_state->pzOptArg == NUL)
512              opt_state->pzOptArg = NULL;
513         else {
514             AGDUPSTR(opt_state->pzOptArg, opt_state->pzOptArg, "opt arg");
515             opt_state->flags |= OPTST_ALLOC_ARG;
516         }
517 
518     } else {
519         if (*opt_state->pzOptArg == NUL)
520              opt_state->pzOptArg = zNil;
521         else {
522             AGDUPSTR(opt_state->pzOptArg, opt_state->pzOptArg, "opt arg");
523             opt_state->flags |= OPTST_ALLOC_ARG;
524         }
525     }
526 
527     {
528         tOptionLoadMode sv = option_load_mode;
529         option_load_mode = load_mode;
530         handle_opt(opts, opt_state);
531         option_load_mode = sv;
532     }
533 }
534 
535 /*=export_func  optionLoadLine
536  *
537  * what:  process a string for an option name and value
538  *
539  * arg:   tOptions *,   opts,  program options descriptor
540  * arg:   char const *, line,  NUL-terminated text
541  *
542  * doc:
543  *
544  *  This is a client program callable routine for setting options from, for
545  *  example, the contents of a file that they read in.  Only one option may
546  *  appear in the text.  It will be treated as a normal (non-preset) option.
547  *
548  *  When passed a pointer to the option struct and a string, it will find
549  *  the option named by the first token on the string and set the option
550  *  argument to the remainder of the string.  The caller must NUL terminate
551  *  the string.  The caller need not skip over any introductory hyphens.
552  *  Any embedded new lines will be included in the option
553  *  argument.  If the input looks like one or more quoted strings, then the
554  *  input will be "cooked".  The "cooking" is identical to the string
555  *  formation used in AutoGen definition files (@pxref{basic expression}),
556  *  except that you may not use backquotes.
557  *
558  * err:   Invalid options are silently ignored.  Invalid option arguments
559  *        will cause a warning to print, but the function should return.
560 =*/
561 void
562 optionLoadLine(tOptions * opts, char const * line)
563 {
564     tOptState st = OPTSTATE_INITIALIZER(SET);
565     char *    pz;
566     proc_state_mask_t sv_flags = opts->fOptSet;
567     opts->fOptSet &= ~OPTPROC_ERRSTOP;
568     AGDUPSTR(pz, line, "opt line");
569     load_opt_line(opts, &st, pz, DIRECTION_CALLED, OPTION_LOAD_COOKED);
570     AGFREE(pz);
571     opts->fOptSet = sv_flags;
572 }
573 /** @}
574  *
575  * Local Variables:
576  * mode: C
577  * c-file-style: "stroustrup"
578  * indent-tabs-mode: nil
579  * End:
580  * end of autoopts/load.c */
581