Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
/*	$NetBSD: postconf_edit.c,v 1.2 2017/02/14 01:16:46 christos Exp $	*/

/*++
/* NAME
/*	postconf_edit 3
/* SUMMARY
/*	edit main.cf or master.cf
/* SYNOPSIS
/*	#include <postconf.h>
/*
/*	void	pcf_edit_main(mode, argc, argv)
/*	int	mode;
/*	int	argc;
/*	char	**argv;
/*
/*	void	pcf_edit_master(mode, argc, argv)
/*	int	mode;
/*	int	argc;
/*	char	**argv;
/* DESCRIPTION
/*	pcf_edit_main() edits the \fBmain.cf\fR configuration file.
/*	It replaces or adds parameter settings given as "\fIname=value\fR"
/*	pairs given on the command line, or removes parameter
/*	settings given as "\fIname\fR" on the command line.  The
/*	file is copied to a temporary file then renamed into place.
/*
/*	pcf_edit_master() edits the \fBmaster.cf\fR configuration
/*	file.  The file is copied to a temporary file then renamed
/*	into place. Depending on the flags in \fBmode\fR:
/* .IP PCF_MASTER_ENTRY
/*	With PCF_EDIT_CONF, pcf_edit_master() replaces or adds
/*	entire master.cf entries, specified on the command line as
/*	"\fIname/type = name type private unprivileged chroot wakeup
/*	process_limit command...\fR".
/*
/*	With PCF_EDIT_EXCL or PCF_COMMENT_OUT, pcf_edit_master()
/*	removes or comments out entries specified on the command
/*	line as "\fIname/type\fR.
/* .IP PCF_MASTER_FLD
/*	With PCF_EDIT_CONF, pcf_edit_master() replaces the value
/*	of specific service attributes, specified on the command
/*	line as "\fIname/type/attribute = value\fR".
/* .IP PCF_MASTER_PARAM
/*	With PCF_EDIT_CONF, pcf_edit_master() replaces or adds the
/*	value of service parameters, specified on the command line
/*	as "\fIname/type/parameter = value\fR".
/*
/*	With PCF_EDIT_EXCL, pcf_edit_master() removes service
/*	parameters specified on the command line as "\fIparametername\fR".
/* DIAGNOSTICS
/*	Problems are reported to the standard error stream.
/* FILES
/*	/etc/postfix/main.cf, Postfix configuration parameters
/*	/etc/postfix/main.cf.tmp, temporary name
/*	/etc/postfix/master.cf, Postfix configuration parameters
/*	/etc/postfix/master.cf.tmp, temporary name
/* LICENSE
/* .ad
/* .fi
/*	The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/*	Wietse Venema
/*	IBM T.J. Watson Research
/*	P.O. Box 704
/*	Yorktown Heights, NY 10598, USA
/*--*/

/* System library. */

#include <sys_defs.h>
#include <string.h>
#include <ctype.h>

/* Utility library. */

#include <msg.h>
#include <mymalloc.h>
#include <htable.h>
#include <vstring.h>
#include <vstring_vstream.h>
#include <edit_file.h>
#include <readlline.h>
#include <stringops.h>
#include <split_at.h>

/* Global library. */

#include <mail_params.h>

/* Application-specific. */

#include <postconf.h>

#define STR(x) vstring_str(x)

/* pcf_find_cf_info - pass-through non-content line, return content or null */

static char *pcf_find_cf_info(VSTRING *buf, VSTREAM *dst)
{
    char   *cp;

    for (cp = STR(buf); ISSPACE(*cp) /* including newline */ ; cp++)
	 /* void */ ;
    /* Pass-through comment, all-whitespace, or empty line. */
    if (*cp == '#' || *cp == 0) {
	vstream_fputs(STR(buf), dst);
	return (0);
    } else {
	return (cp);
    }
}

/* pcf_next_cf_line - return next content line, pass non-content */

static char *pcf_next_cf_line(VSTRING *buf, VSTREAM *src, VSTREAM *dst, int *lineno)
{
    char   *cp;

    while (vstring_get(buf, src) != VSTREAM_EOF) {
	if (lineno)
	    *lineno += 1;
	if ((cp = pcf_find_cf_info(buf, dst)) != 0)
	    return (cp);
    }
    return (0);
}

/* pcf_gobble_cf_line - accumulate multi-line content, pass non-content */

static void pcf_gobble_cf_line(VSTRING *full_entry_buf, VSTRING *line_buf,
			            VSTREAM *src, VSTREAM *dst, int *lineno)
{
    int     ch;

    vstring_strcpy(full_entry_buf, STR(line_buf));
    for (;;) {
	if ((ch = VSTREAM_GETC(src)) != VSTREAM_EOF)
	    vstream_ungetc(src, ch);
	if ((ch != '#' && !ISSPACE(ch))
	    || vstring_get(line_buf, src) == VSTREAM_EOF)
	    break;
	lineno += 1;
	if (pcf_find_cf_info(line_buf, dst))
	    vstring_strcat(full_entry_buf, STR(line_buf));
    }
}

/* pcf_edit_main - edit main.cf file */

void    pcf_edit_main(int mode, int argc, char **argv)
{
    char   *path;
    EDIT_FILE *ep;
    VSTREAM *src;
    VSTREAM *dst;
    VSTRING *buf = vstring_alloc(100);
    VSTRING *key = vstring_alloc(10);
    char   *cp;
    char   *pattern;
    char   *edit_value;
    HTABLE *table;
    struct cvalue {
	char   *value;
	int     found;
    };
    struct cvalue *cvalue;
    HTABLE_INFO **ht_info;
    HTABLE_INFO **ht;
    int     interesting;
    const char *err;

    /*
     * Store command-line parameters for quick lookup.
     */
    table = htable_create(argc);
    while ((cp = *argv++) != 0) {
	if (strchr(cp, '\n') != 0)
	    msg_fatal("-e, -X, or -# accepts no multi-line input");
	while (ISSPACE(*cp))
	    cp++;
	if (*cp == '#')
	    msg_fatal("-e, -X, or -# accepts no comment input");
	if (mode & PCF_EDIT_CONF) {
	    if ((err = split_nameval(cp, &pattern, &edit_value)) != 0)
		msg_fatal("%s: \"%s\"", err, cp);
	} else if (mode & (PCF_COMMENT_OUT | PCF_EDIT_EXCL)) {
	    if (*cp == 0)
		msg_fatal("-X or -# requires non-blank parameter names");
	    if (strchr(cp, '=') != 0)
		msg_fatal("-X or -# requires parameter names without value");
	    pattern = cp;
	    trimblanks(pattern, 0);
	    edit_value = 0;
	} else {
	    msg_panic("pcf_edit_main: unknown mode %d", mode);
	}
	cvalue = (struct cvalue *) mymalloc(sizeof(*cvalue));
	cvalue->value = edit_value;
	cvalue->found = 0;
	htable_enter(table, pattern, (void *) cvalue);
    }

    /*
     * Open a temp file for the result. This uses a deterministic name so we
     * don't leave behind thrash with random names.
     */
    pcf_set_config_dir();
    path = concatenate(var_config_dir, "/", MAIN_CONF_FILE, (char *) 0);
    if ((ep = edit_file_open(path, O_CREAT | O_WRONLY, 0644)) == 0)
	msg_fatal("open %s%s: %m", path, EDIT_FILE_SUFFIX);
    dst = ep->tmp_fp;

    /*
     * Open the original file for input.
     */
    if ((src = vstream_fopen(path, O_RDONLY, 0)) == 0) {
	/* OK to delete, since we control the temp file name exclusively. */
	(void) unlink(ep->tmp_path);
	msg_fatal("open %s for reading: %m", path);
    }

    /*
     * Copy original file to temp file, while replacing parameters on the
     * fly. Issue warnings for names found multiple times.
     */
#define STR(x) vstring_str(x)

    interesting = 0;
    while ((cp = pcf_next_cf_line(buf, src, dst, (int *) 0)) != 0) {
	/* Copy, skip or replace continued text. */
	if (cp > STR(buf)) {
	    if (interesting == 0)
		vstream_fputs(STR(buf), dst);
	    else if (mode & PCF_COMMENT_OUT)
		vstream_fprintf(dst, "#%s", STR(buf));
	}
	/* Copy or replace start of logical line. */
	else {
	    vstring_strncpy(key, cp, strcspn(cp, CHARS_SPACE "="));
	    cvalue = (struct cvalue *) htable_find(table, STR(key));
	    if ((interesting = !!cvalue) != 0) {
		if (cvalue->found++ == 1)
		    msg_warn("%s: multiple entries for \"%s\"", path, STR(key));
		if (mode & PCF_EDIT_CONF)
		    vstream_fprintf(dst, "%s = %s\n", STR(key), cvalue->value);
		else if (mode & PCF_COMMENT_OUT)
		    vstream_fprintf(dst, "#%s", cp);
	    } else {
		vstream_fputs(STR(buf), dst);
	    }
	}
    }

    /*
     * Generate new entries for parameters that were not found.
     */
    if (mode & PCF_EDIT_CONF) {
	for (ht_info = ht = htable_list(table); *ht; ht++) {
	    cvalue = (struct cvalue *) ht[0]->value;
	    if (cvalue->found == 0)
		vstream_fprintf(dst, "%s = %s\n", ht[0]->key, cvalue->value);
	}
	myfree((void *) ht_info);
    }

    /*
     * When all is well, rename the temp file to the original one.
     */
    if (vstream_fclose(src))
	msg_fatal("read %s: %m", path);
    if (edit_file_close(ep) != 0)
	msg_fatal("close %s%s: %m", path, EDIT_FILE_SUFFIX);

    /*
     * Cleanup.
     */
    myfree(path);
    vstring_free(buf);
    vstring_free(key);
    htable_free(table, myfree);
}

 /*
  * Data structure to hold a master.cf edit request.
  */
typedef struct {
    int     match_count;		/* hit count */
    const char *raw_text;		/* unparsed command-line argument */
    char   *parsed_text;		/* destructive parse */
    ARGV   *service_pattern;		/* service name, type, ... */
    int     field_number;		/* attribute field number */
    const char *param_pattern;		/* parameter name */
    char   *edit_value;			/* value substring */
} PCF_MASTER_EDIT_REQ;

/* pcf_edit_master - edit master.cf file */

void    pcf_edit_master(int mode, int argc, char **argv)
{
    const char *myname = "pcf_edit_master";
    char   *path;
    EDIT_FILE *ep;
    VSTREAM *src;
    VSTREAM *dst;
    VSTRING *line_buf = vstring_alloc(100);
    VSTRING *parse_buf = vstring_alloc(100);
    int     lineno;
    PCF_MASTER_ENT *new_entry;
    VSTRING *full_entry_buf = vstring_alloc(100);
    char   *cp;
    char   *pattern;
    int     service_name_type_matched;
    const char *err;
    PCF_MASTER_EDIT_REQ *edit_reqs;
    PCF_MASTER_EDIT_REQ *req;
    int     num_reqs = argc;
    const char *edit_opts = "-Me, -Fe, -Pe, -X, or -#";
    char   *service_name;
    char   *service_type;

    /*
     * Sanity check.
     */
    if (num_reqs <= 0)
	msg_panic("%s: empty argument list", myname);

    /*
     * Preprocessing: split pattern=value, then split the pattern components.
     */
    edit_reqs = (PCF_MASTER_EDIT_REQ *) mymalloc(sizeof(*edit_reqs) * num_reqs);
    for (req = edit_reqs; *argv != 0; req++, argv++) {
	req->match_count = 0;
	req->raw_text = *argv;
	cp = req->parsed_text = mystrdup(req->raw_text);
	if (strchr(cp, '\n') != 0)
	    msg_fatal("%s accept no multi-line input", edit_opts);
	while (ISSPACE(*cp))
	    cp++;
	if (*cp == '#')
	    msg_fatal("%s accept no comment input", edit_opts);
	/* Separate the pattern from the value. */
	if (mode & PCF_EDIT_CONF) {
	    if ((err = split_nameval(cp, &pattern, &req->edit_value)) != 0)
		msg_fatal("%s: \"%s\"", err, req->raw_text);
#if 0
	    if ((mode & PCF_MASTER_PARAM)
	    && req->edit_value[strcspn(req->edit_value, PCF_MASTER_BLANKS)])
		msg_fatal("whitespace in parameter value: \"%s\"",
			  req->raw_text);
#endif
	} else if (mode & (PCF_COMMENT_OUT | PCF_EDIT_EXCL)) {
	    if (strchr(cp, '=') != 0)
		msg_fatal("-X or -# requires names without value");
	    pattern = cp;
	    trimblanks(pattern, 0);
	    req->edit_value = 0;
	} else {
	    msg_panic("%s: unknown mode %d", myname, mode);
	}

#define PCF_MASTER_MASK (PCF_MASTER_ENTRY | PCF_MASTER_FLD | PCF_MASTER_PARAM)

	/*
	 * Split name/type or name/type/whatever pattern into components.
	 */
	switch (mode & PCF_MASTER_MASK) {
	case PCF_MASTER_ENTRY:
	    if ((req->service_pattern =
		 pcf_parse_service_pattern(pattern, 2, 2)) == 0)
		msg_fatal("-Me, -MX or -M# requires service_name/type");
	    break;
	case PCF_MASTER_FLD:
	    if ((req->service_pattern =
		 pcf_parse_service_pattern(pattern, 3, 3)) == 0)
		msg_fatal("-Fe or -FX requires service_name/type/field_name");
	    req->field_number =
		pcf_parse_field_pattern(req->service_pattern->argv[2]);
	    if (pcf_is_magic_field_pattern(req->field_number))
		msg_fatal("-Fe does not accept wild-card field name");
	    if ((mode & PCF_EDIT_CONF)
		&& req->field_number < PCF_MASTER_FLD_CMD
	    && req->edit_value[strcspn(req->edit_value, PCF_MASTER_BLANKS)])
		msg_fatal("-Fe does not accept whitespace in non-command field");
	    break;
	case PCF_MASTER_PARAM:
	    if ((req->service_pattern =
		 pcf_parse_service_pattern(pattern, 3, 3)) == 0)
		msg_fatal("-Pe or -PX requires service_name/type/parameter");
	    req->param_pattern = req->service_pattern->argv[2];
	    if (PCF_IS_MAGIC_PARAM_PATTERN(req->param_pattern))
		msg_fatal("-Pe does not accept wild-card parameter name");
	    if ((mode & PCF_EDIT_CONF)
	    && req->edit_value[strcspn(req->edit_value, PCF_MASTER_BLANKS)])
		msg_fatal("-Pe does not accept whitespace in parameter value");
	    break;
	default:
	    msg_panic("%s: unknown edit mode %d", myname, mode);
	}
    }

    /*
     * Open a temp file for the result. This uses a deterministic name so we
     * don't leave behind thrash with random names.
     */
    pcf_set_config_dir();
    path = concatenate(var_config_dir, "/", MASTER_CONF_FILE, (char *) 0);
    if ((ep = edit_file_open(path, O_CREAT | O_WRONLY, 0644)) == 0)
	msg_fatal("open %s%s: %m", path, EDIT_FILE_SUFFIX);
    dst = ep->tmp_fp;

    /*
     * Open the original file for input.
     */
    if ((src = vstream_fopen(path, O_RDONLY, 0)) == 0) {
	/* OK to delete, since we control the temp file name exclusively. */
	(void) unlink(ep->tmp_path);
	msg_fatal("open %s for reading: %m", path);
    }

    /*
     * Copy original file to temp file, while replacing service entries on
     * the fly.
     */
    service_name_type_matched = 0;
    new_entry = 0;
    lineno = 0;
    while ((cp = pcf_next_cf_line(parse_buf, src, dst, &lineno)) != 0) {
	vstring_strcpy(line_buf, STR(parse_buf));

	/*
	 * Copy, skip or replace continued text.
	 */
	if (cp > STR(parse_buf)) {
	    if (service_name_type_matched == 0)
		vstream_fputs(STR(line_buf), dst);
	    else if (mode & PCF_COMMENT_OUT)
		vstream_fprintf(dst, "#%s", STR(line_buf));
	}

	/*
	 * Copy or replace (start of) logical line.
	 */
	else {
	    service_name_type_matched = 0;

	    /*
	     * Parse out the service name and type.
	     */
	    if ((service_name = mystrtok(&cp, PCF_MASTER_BLANKS)) == 0
		|| (service_type = mystrtok(&cp, PCF_MASTER_BLANKS)) == 0)
		msg_fatal("file %s: line %d: specify service name and type "
			  "on the same line", path, lineno);
	    if (strchr(service_name, '='))
		msg_fatal("file %s: line %d: service name syntax \"%s\" is "
			  "unsupported with %s", path, lineno, service_name,
			  edit_opts);
	    if (service_type[strcspn(service_type, "=/")] != 0)
		msg_fatal("file %s: line %d: "
			"service type syntax \"%s\" is unsupported with %s",
			  path, lineno, service_type, edit_opts);

	    /*
	     * Match each service pattern.
	     */
	    for (req = edit_reqs; req < edit_reqs + num_reqs; req++) {
		if (PCF_MATCH_SERVICE_PATTERN(req->service_pattern,
					      service_name,
					      service_type)) {
		    service_name_type_matched = 1;	/* Sticky flag */
		    req->match_count += 1;

		    /*
		     * Generate replacement master.cf entries.
		     */
		    if ((mode & PCF_EDIT_CONF)
			|| ((mode & PCF_MASTER_PARAM) && (mode & PCF_EDIT_EXCL))) {
			switch (mode & PCF_MASTER_MASK) {

			    /*
			     * Replace master.cf entry field or parameter
			     * value.
			     */
			case PCF_MASTER_FLD:
			case PCF_MASTER_PARAM:
			    if (new_entry == 0) {
				/* Gobble up any continuation lines. */
				pcf_gobble_cf_line(full_entry_buf, line_buf,
						   src, dst, &lineno);
				new_entry = (PCF_MASTER_ENT *)
				    mymalloc(sizeof(*new_entry));
				if ((err = pcf_parse_master_entry(new_entry,
						 STR(full_entry_buf))) != 0)
				    msg_fatal("file %s: line %d: %s",
					      path, lineno, err);
			    }
			    if (mode & PCF_MASTER_FLD) {
				pcf_edit_master_field(new_entry,
						      req->field_number,
						      req->edit_value);
			    } else {
				pcf_edit_master_param(new_entry, mode,
						      req->param_pattern,
						      req->edit_value);
			    }
			    break;

			    /*
			     * Replace entire master.cf entry.
			     */
			case PCF_MASTER_ENTRY:
			    if (new_entry != 0)
				pcf_free_master_entry(new_entry);
			    new_entry = (PCF_MASTER_ENT *)
				mymalloc(sizeof(*new_entry));
			    if ((err = pcf_parse_master_entry(new_entry,
						     req->edit_value)) != 0)
				msg_fatal("%s: \"%s\"", err, req->raw_text);
			    break;
			default:
			    msg_panic("%s: unknown edit mode %d", myname, mode);
			}
		    }
		}
	    }

	    /*
	     * Pass through or replace the current input line.
	     */
	    if (new_entry) {
		pcf_print_master_entry(dst, PCF_FOLD_LINE, new_entry);
		pcf_free_master_entry(new_entry);
		new_entry = 0;
	    } else if (service_name_type_matched == 0) {
		vstream_fputs(STR(line_buf), dst);
	    } else if (mode & PCF_COMMENT_OUT) {
		vstream_fprintf(dst, "#%s", STR(line_buf));
	    }
	}
    }

    /*
     * Postprocessing: when editing entire service entries, generate new
     * entries for services not found. Otherwise (editing fields or
     * parameters), "service not found" is a fatal error.
     */
    for (req = edit_reqs; req < edit_reqs + num_reqs; req++) {
	if (req->match_count == 0) {
	    if ((mode & PCF_MASTER_ENTRY) && (mode & PCF_EDIT_CONF)) {
		new_entry = (PCF_MASTER_ENT *) mymalloc(sizeof(*new_entry));
		if ((err = pcf_parse_master_entry(new_entry, req->edit_value)) != 0)
		    msg_fatal("%s: \"%s\"", err, req->raw_text);
		pcf_print_master_entry(dst, PCF_FOLD_LINE, new_entry);
		pcf_free_master_entry(new_entry);
	    } else if ((mode & PCF_MASTER_ENTRY) == 0) {
		msg_warn("unmatched service_name/type: \"%s\"", req->raw_text);
	    }
	}
    }

    /*
     * When all is well, rename the temp file to the original one.
     */
    if (vstream_fclose(src))
	msg_fatal("read %s: %m", path);
    if (edit_file_close(ep) != 0)
	msg_fatal("close %s%s: %m", path, EDIT_FILE_SUFFIX);

    /*
     * Cleanup.
     */
    myfree(path);
    vstring_free(line_buf);
    vstring_free(parse_buf);
    vstring_free(full_entry_buf);
    for (req = edit_reqs; req < edit_reqs + num_reqs; req++) {
	argv_free(req->service_pattern);
	myfree(req->parsed_text);
    }
    myfree((void *) edit_reqs);
}