xref: /freebsd/contrib/ntp/sntp/libopts/load.c (revision 93e779a26c651610ac6e7986d67ecc9ed2cadcbf)
1 
2 /**
3  *  \file load.c
4  *
5  *  This file contains the routines that deal with processing text strings
6  *  for options, either from a NUL-terminated string passed in or from an
7  *  rc/ini file.
8  *
9  * @addtogroup autoopts
10  * @{
11  */
12 /*
13  *  This file is part of AutoOpts, a companion to AutoGen.
14  *  AutoOpts is free software.
15  *  AutoOpts is Copyright (C) 1992-2015 by Bruce Korb - all rights reserved
16  *
17  *  AutoOpts is available under any one of two licenses.  The license
18  *  in use must be one of these two and the choice is under the control
19  *  of the user of the license.
20  *
21  *   The GNU Lesser General Public License, version 3 or later
22  *      See the files "COPYING.lgplv3" and "COPYING.gplv3"
23  *
24  *   The Modified Berkeley Software Distribution License
25  *      See the file "COPYING.mbsd"
26  *
27  *  These files have the following sha256 sums:
28  *
29  *  8584710e9b04216a394078dc156b781d0b47e1729104d666658aecef8ee32e95  COPYING.gplv3
30  *  4379e7444a0e2ce2b12dd6f5a52a27a4d02d39d247901d3285c88cf0d37f477b  COPYING.lgplv3
31  *  13aa749a5b0a454917a944ed8fffc530b784f5ead522b1aacaf4ec8aa55a6239  COPYING.mbsd
32  */
33 
34 /* = = = START-STATIC-FORWARD = = = */
35 static bool
36 get_realpath(char * buf, size_t b_sz);
37 
38 static bool
39 add_prog_path(char * buf, int b_sz, char const * fname, char const * prg_path);
40 
41 static bool
42 add_env_val(char * buf, int buf_sz, char const * name);
43 
44 static char *
45 assemble_arg_val(char * txt, tOptionLoadMode mode);
46 
47 static char *
48 trim_quotes(char * arg);
49 
50 static bool
51 direction_ok(opt_state_mask_t f, int dir);
52 /* = = = END-STATIC-FORWARD = = = */
53 
54 static bool
55 get_realpath(char * buf, size_t b_sz)
56 {
57 #if defined(HAVE_CANONICALIZE_FILE_NAME)
58     {
59         size_t name_len;
60 
61         char * pz = canonicalize_file_name(buf);
62         if (pz == NULL)
63             return false;
64 
65         name_len = strlen(pz);
66         if (name_len >= (size_t)b_sz) {
67             free(pz);
68             return false;
69         }
70 
71         memcpy(buf, pz, name_len + 1);
72         free(pz);
73     }
74 
75 #elif defined(HAVE_REALPATH)
76     {
77         size_t name_len;
78         char z[PATH_MAX+1];
79 
80         if (realpath(buf, z) == NULL)
81             return false;
82 
83         name_len = strlen(z);
84         if (name_len >= b_sz)
85             return false;
86 
87         memcpy(buf, z, name_len + 1);
88     }
89 #endif
90     return true;
91 }
92 
93 /*=export_func  optionMakePath
94  * private:
95  *
96  * what:  translate and construct a path
97  * arg:   + char *       + p_buf     + The result buffer +
98  * arg:   + int          + b_sz      + The size of this buffer +
99  * arg:   + char const * + fname     + The input name +
100  * arg:   + char const * + prg_path  + The full path of the current program +
101  *
102  * ret-type: bool
103  * ret-desc: true if the name was handled, otherwise false.
104  *           If the name does not start with ``$'', then it is handled
105  *           simply by copying the input name to the output buffer and
106  *           resolving the name with either
107  *           @code{canonicalize_file_name(3GLIBC)} or @code{realpath(3C)}.
108  *
109  * doc:
110  *
111  *  This routine will copy the @code{pzName} input name into the
112  *  @code{pzBuf} output buffer, not exceeding @code{bufSize} bytes.  If the
113  *  first character of the input name is a @code{'$'} character, then there
114  *  is special handling:
115  *  @*
116  *  @code{$$} is replaced with the directory name of the @code{pzProgPath},
117  *  searching @code{$PATH} if necessary.
118  *  @*
119  *  @code{$@} is replaced with the AutoGen package data installation directory
120  *  (aka @code{pkgdatadir}).
121  *  @*
122  *  @code{$NAME} is replaced by the contents of the @code{NAME} environment
123  *  variable.  If not found, the search fails.
124  *
125  *  Please note: both @code{$$} and @code{$NAME} must be at the start of the
126  *     @code{pzName} string and must either be the entire string or be followed
127  *     by the @code{'/'} (backslash on windows) character.
128  *
129  * err:  @code{false} is returned if:
130  *       @*
131  *       @bullet{} The input name exceeds @code{bufSize} bytes.
132  *       @*
133  *       @bullet{} @code{$$}, @code{$@@} or @code{$NAME} is not the full string
134  *                 and the next character is not '/'.
135  *       @*
136  *       @bullet{} libopts was built without PKGDATADIR defined and @code{$@@}
137  *                 was specified.
138  *       @*
139  *       @bullet{} @code{NAME} is not a known environment variable
140  *       @*
141  *       @bullet{} @code{canonicalize_file_name} or @code{realpath} return
142  *                 errors (cannot resolve the resulting path).
143 =*/
144 bool
145 optionMakePath(char * p_buf, int b_sz, char const * fname, char const * prg_path)
146 {
147     {
148         size_t len = strlen(fname);
149 
150         if (((size_t)b_sz <= len) || (len == 0))
151             return false;
152     }
153 
154     /*
155      *  IF not an environment variable, just copy the data
156      */
157     if (*fname != '$') {
158         char   const * src = fname;
159         char * dst = p_buf;
160         int    ct  = b_sz;
161 
162         for (;;) {
163             if ( (*(dst++) = *(src++)) == NUL)
164                 break;
165             if (--ct <= 0)
166                 return false;
167         }
168     }
169 
170     /*
171      *  IF the name starts with "$$", then it must be "$$" or
172      *  it must start with "$$/".  In either event, replace the "$$"
173      *  with the path to the executable and append a "/" character.
174      */
175     else switch (fname[1]) {
176     case NUL:
177         return false;
178 
179     case '$':
180         if (! add_prog_path(p_buf, b_sz, fname, prg_path))
181             return false;
182         break;
183 
184     case '@':
185         if (program_pkgdatadir[0] == NUL)
186             return false;
187 
188         if (snprintf(p_buf, (size_t)b_sz, "%s%s",
189                      program_pkgdatadir, fname + 2) >= b_sz)
190             return false;
191         break;
192 
193     default:
194         if (! add_env_val(p_buf, b_sz, fname))
195             return false;
196     }
197 
198     return get_realpath(p_buf, b_sz);
199 }
200 
201 /**
202  * convert a leading "$$" into a path to the executable.
203  */
204 static bool
205 add_prog_path(char * buf, int b_sz, char const * fname, char const * prg_path)
206 {
207     char const *   path;
208     char const *   pz;
209     int     skip = 2;
210 
211     switch (fname[2]) {
212     case DIRCH:
213         skip = 3;
214     case NUL:
215         break;
216     default:
217         return false;
218     }
219 
220     /*
221      *  See if the path is included in the program name.
222      *  If it is, we're done.  Otherwise, we have to hunt
223      *  for the program using "pathfind".
224      */
225     if (strchr(prg_path, DIRCH) != NULL)
226         path = prg_path;
227     else {
228         path = pathfind(getenv("PATH"), (char *)prg_path, "rx");
229 
230         if (path == NULL)
231             return false;
232     }
233 
234     pz = strrchr(path, DIRCH);
235 
236     /*
237      *  IF we cannot find a directory name separator,
238      *  THEN we do not have a path name to our executable file.
239      */
240     if (pz == NULL)
241         return false;
242 
243     fname += skip;
244 
245     /*
246      *  Concatenate the file name to the end of the executable path.
247      *  The result may be either a file or a directory.
248      */
249     if ((unsigned)(pz - path) + 1 + strlen(fname) >= (unsigned)b_sz)
250         return false;
251 
252     memcpy(buf, path, (size_t)((pz - path)+1));
253     strcpy(buf + (pz - path) + 1, fname);
254 
255     /*
256      *  If the "path" path was gotten from "pathfind()", then it was
257      *  allocated and we need to deallocate it.
258      */
259     if (path != prg_path)
260         AGFREE(path);
261     return true;
262 }
263 
264 /**
265  * Add an environment variable value.
266  */
267 static bool
268 add_env_val(char * buf, int buf_sz, char const * name)
269 {
270     char * dir_part = buf;
271 
272     for (;;) {
273         int ch = (int)*++name;
274         if (! IS_VALUE_NAME_CHAR(ch))
275             break;
276         *(dir_part++) = (char)ch;
277     }
278 
279     if (dir_part == buf)
280         return false;
281 
282     *dir_part = NUL;
283 
284     dir_part = getenv(buf);
285 
286     /*
287      *  Environment value not found -- skip the home list entry
288      */
289     if (dir_part == NULL)
290         return false;
291 
292     if (strlen(dir_part) + 1 + strlen(name) >= (unsigned)buf_sz)
293         return false;
294 
295     sprintf(buf, "%s%s", dir_part, name);
296     return true;
297 }
298 
299 /**
300  * Trim leading and trailing white space.
301  * If we are cooking the text and the text is quoted, then "cook"
302  * the string.  To cook, the string must be quoted.
303  *
304  * @param[in,out] txt  the input and output string
305  * @param[in]     mode the handling mode (cooking method)
306  */
307 LOCAL void
308 munge_str(char * txt, tOptionLoadMode mode)
309 {
310     char * pzE;
311 
312     if (mode == OPTION_LOAD_KEEP)
313         return;
314 
315     if (IS_WHITESPACE_CHAR(*txt)) {
316         char * src = SPN_WHITESPACE_CHARS(txt+1);
317         size_t l   = strlen(src) + 1;
318         memmove(txt, src, l);
319         pzE = txt + l - 1;
320 
321     } else
322         pzE = txt + strlen(txt);
323 
324     pzE  = SPN_WHITESPACE_BACK(txt, pzE);
325     *pzE = NUL;
326 
327     if (mode == OPTION_LOAD_UNCOOKED)
328         return;
329 
330     switch (*txt) {
331     default: return;
332     case '"':
333     case '\'': break;
334     }
335 
336     switch (pzE[-1]) {
337     default: return;
338     case '"':
339     case '\'': break;
340     }
341 
342     (void)ao_string_cook(txt, NULL);
343 }
344 
345 static char *
346 assemble_arg_val(char * txt, tOptionLoadMode mode)
347 {
348     char * end = strpbrk(txt, ARG_BREAK_STR);
349     int    space_break;
350 
351     /*
352      *  Not having an argument to a configurable name is okay.
353      */
354     if (end == NULL)
355         return txt + strlen(txt);
356 
357     /*
358      *  If we are keeping all whitespace, then the  modevalue starts with the
359      *  character that follows the end of the configurable name, regardless
360      *  of which character caused it.
361      */
362     if (mode == OPTION_LOAD_KEEP) {
363         *(end++) = NUL;
364         return end;
365     }
366 
367     /*
368      *  If the name ended on a white space character, remember that
369      *  because we'll have to skip over an immediately following ':' or '='
370      *  (and the white space following *that*).
371      */
372     space_break = IS_WHITESPACE_CHAR(*end);
373     *(end++) = NUL;
374 
375     end = SPN_WHITESPACE_CHARS(end);
376     if (space_break && ((*end == ':') || (*end == '=')))
377         end = SPN_WHITESPACE_CHARS(end+1);
378 
379     return end;
380 }
381 
382 static char *
383 trim_quotes(char * arg)
384 {
385     switch (*arg) {
386     case '"':
387     case '\'':
388         ao_string_cook(arg, NULL);
389     }
390     return arg;
391 }
392 
393 /**
394  * See if the option is to be processed in the current scan direction
395  * (-1 or +1).
396  */
397 static bool
398 direction_ok(opt_state_mask_t f, int dir)
399 {
400     if (dir == 0)
401         return true;
402 
403     switch (f & (OPTST_IMM|OPTST_DISABLE_IMM)) {
404     case 0:
405         /*
406          *  The selected option has no immediate action.
407          *  THEREFORE, if the direction is PRESETTING
408          *  THEN we skip this option.
409          */
410         if (PRESETTING(dir))
411             return false;
412         break;
413 
414     case OPTST_IMM:
415         if (PRESETTING(dir)) {
416             /*
417              *  We are in the presetting direction with an option we handle
418              *  immediately for enablement, but normally for disablement.
419              *  Therefore, skip if disabled.
420              */
421             if ((f & OPTST_DISABLED) == 0)
422                 return false;
423         } else {
424             /*
425              *  We are in the processing direction with an option we handle
426              *  immediately for enablement, but normally for disablement.
427              *  Therefore, skip if NOT disabled.
428              */
429             if ((f & OPTST_DISABLED) != 0)
430                 return false;
431         }
432         break;
433 
434     case OPTST_DISABLE_IMM:
435         if (PRESETTING(dir)) {
436             /*
437              *  We are in the presetting direction with an option we handle
438              *  immediately for disablement, but normally for disablement.
439              *  Therefore, skip if NOT disabled.
440              */
441             if ((f & OPTST_DISABLED) != 0)
442                 return false;
443         } else {
444             /*
445              *  We are in the processing direction with an option we handle
446              *  immediately for disablement, but normally for disablement.
447              *  Therefore, skip if disabled.
448              */
449             if ((f & OPTST_DISABLED) == 0)
450                 return false;
451         }
452         break;
453 
454     case OPTST_IMM|OPTST_DISABLE_IMM:
455         /*
456          *  The selected option is always for immediate action.
457          *  THEREFORE, if the direction is PROCESSING
458          *  THEN we skip this option.
459          */
460         if (PROCESSING(dir))
461             return false;
462         break;
463     }
464     return true;
465 }
466 
467 /**
468  *  Load an option from a block of text.  The text must start with the
469  *  configurable/option name and be followed by its associated value.
470  *  That value may be processed in any of several ways.  See "tOptionLoadMode"
471  *  in autoopts.h.
472  *
473  * @param[in,out] opts       program options descriptor
474  * @param[in,out] opt_state  option processing state
475  * @param[in,out] line       source line with long option name in it
476  * @param[in]     direction  current processing direction (preset or not)
477  * @param[in]     load_mode  option loading mode (OPTION_LOAD_*)
478  */
479 LOCAL void
480 load_opt_line(tOptions * opts, tOptState * opt_state, char * line,
481               tDirection direction, tOptionLoadMode load_mode )
482 {
483     /*
484      * When parsing a stored line, we only look at the characters after
485      * a hyphen.  Long names must always be at least two characters and
486      * short options are always exactly one character long.
487      */
488     line = SPN_LOAD_LINE_SKIP_CHARS(line);
489 
490     {
491         char * arg = assemble_arg_val(line, load_mode);
492 
493         if (IS_OPTION_NAME_CHAR(line[1])) {
494 
495             if (! SUCCESSFUL(opt_find_long(opts, line, opt_state)))
496                 return;
497 
498         } else if (! SUCCESSFUL(opt_find_short(opts, *line, opt_state)))
499             return;
500 
501         if ((! CALLED(direction)) && (opt_state->flags & OPTST_NO_INIT))
502             return;
503 
504         opt_state->pzOptArg = trim_quotes(arg);
505     }
506 
507     if (! direction_ok(opt_state->flags, direction))
508         return;
509 
510     /*
511      *  Fix up the args.
512      */
513     if (OPTST_GET_ARGTYPE(opt_state->pOD->fOptState) == OPARG_TYPE_NONE) {
514         if (*opt_state->pzOptArg != NUL)
515             return;
516         opt_state->pzOptArg = NULL;
517 
518     } else if (opt_state->pOD->fOptState & OPTST_ARG_OPTIONAL) {
519         if (*opt_state->pzOptArg == NUL)
520              opt_state->pzOptArg = NULL;
521         else {
522             AGDUPSTR(opt_state->pzOptArg, opt_state->pzOptArg, "opt arg");
523             opt_state->flags |= OPTST_ALLOC_ARG;
524         }
525 
526     } else {
527         if (*opt_state->pzOptArg == NUL)
528              opt_state->pzOptArg = zNil;
529         else {
530             AGDUPSTR(opt_state->pzOptArg, opt_state->pzOptArg, "opt arg");
531             opt_state->flags |= OPTST_ALLOC_ARG;
532         }
533     }
534 
535     {
536         tOptionLoadMode sv = option_load_mode;
537         option_load_mode = load_mode;
538         handle_opt(opts, opt_state);
539         option_load_mode = sv;
540     }
541 }
542 
543 /*=export_func  optionLoadLine
544  *
545  * what:  process a string for an option name and value
546  *
547  * arg:   tOptions *,   opts,  program options descriptor
548  * arg:   char const *, line,  NUL-terminated text
549  *
550  * doc:
551  *
552  *  This is a client program callable routine for setting options from, for
553  *  example, the contents of a file that they read in.  Only one option may
554  *  appear in the text.  It will be treated as a normal (non-preset) option.
555  *
556  *  When passed a pointer to the option struct and a string, it will find
557  *  the option named by the first token on the string and set the option
558  *  argument to the remainder of the string.  The caller must NUL terminate
559  *  the string.  The caller need not skip over any introductory hyphens.
560  *  Any embedded new lines will be included in the option
561  *  argument.  If the input looks like one or more quoted strings, then the
562  *  input will be "cooked".  The "cooking" is identical to the string
563  *  formation used in AutoGen definition files (@pxref{basic expression}),
564  *  except that you may not use backquotes.
565  *
566  * err:   Invalid options are silently ignored.  Invalid option arguments
567  *        will cause a warning to print, but the function should return.
568 =*/
569 void
570 optionLoadLine(tOptions * opts, char const * line)
571 {
572     tOptState st = OPTSTATE_INITIALIZER(SET);
573     char *    pz;
574     proc_state_mask_t sv_flags = opts->fOptSet;
575     opts->fOptSet &= ~OPTPROC_ERRSTOP;
576     AGDUPSTR(pz, line, "opt line");
577     load_opt_line(opts, &st, pz, DIRECTION_CALLED, OPTION_LOAD_COOKED);
578     AGFREE(pz);
579     opts->fOptSet = sv_flags;
580 }
581 /** @}
582  *
583  * Local Variables:
584  * mode: C
585  * c-file-style: "stroustrup"
586  * indent-tabs-mode: nil
587  * End:
588  * end of autoopts/load.c */
589