summaryrefslogtreecommitdiffstats
path: root/src/exec.c
blob: a3297e889d5d9ddf76bbcf4972fd97c20cc0afee (plain)
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
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
// Copyright © Tavian Barnes <tavianator@tavianator.com>
// SPDX-License-Identifier: 0BSD

#include "exec.h"
#include "alloc.h"
#include "bfstd.h"
#include "bftw.h"
#include "color.h"
#include "config.h"
#include "ctx.h"
#include "diag.h"
#include "dstring.h"
#include "xspawn.h"
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/resource.h>
#include <sys/wait.h>
#include <unistd.h>

/** Print some debugging info. */
BFS_FORMATTER(2, 3)
static void bfs_exec_debug(const struct bfs_exec *execbuf, const char *format, ...) {
	const struct bfs_ctx *ctx = execbuf->ctx;

	if (!bfs_debug(ctx, DEBUG_EXEC, "${blu}")) {
		return;
	}

	if (execbuf->flags & BFS_EXEC_CONFIRM) {
		fputs("-ok", stderr);
	} else {
		fputs("-exec", stderr);
	}
	if (execbuf->flags & BFS_EXEC_CHDIR) {
		fputs("dir", stderr);
	}
	cfprintf(ctx->cerr, "${rs}: ");

	va_list args;
	va_start(args, format);
	vfprintf(stderr, format, args);
	va_end(args);
}

/** Determine the size of a single argument, for comparison to arg_max. */
static size_t bfs_exec_arg_size(const char *arg) {
	return sizeof(arg) + strlen(arg) + 1;
}

/** Even if we can pass a bigger argument list, cap it here. */
#define BFS_EXEC_ARG_MAX (16 << 20)

/** Determine the maximum argv size. */
static size_t bfs_exec_arg_max(const struct bfs_exec *execbuf) {
	long arg_max = sysconf(_SC_ARG_MAX);
	bfs_exec_debug(execbuf, "ARG_MAX: %ld according to sysconf()\n", arg_max);
	if (arg_max < 0) {
		arg_max = BFS_EXEC_ARG_MAX;
		bfs_exec_debug(execbuf, "ARG_MAX: %ld assumed\n", arg_max);
	}

	// We have to share space with the environment variables
	extern char **environ;
	for (char **envp = environ; *envp; ++envp) {
		arg_max -= bfs_exec_arg_size(*envp);
	}
	// Account for the terminating NULL entry
	arg_max -= sizeof(char *);
	bfs_exec_debug(execbuf, "ARG_MAX: %ld remaining after environment variables\n", arg_max);

	// Account for the fixed arguments
	for (size_t i = 0; i < execbuf->tmpl_argc - 1; ++i) {
		arg_max -= bfs_exec_arg_size(execbuf->tmpl_argv[i]);
	}
	// Account for the terminating NULL entry
	arg_max -= sizeof(char *);
	bfs_exec_debug(execbuf, "ARG_MAX: %ld remaining after fixed arguments\n", arg_max);

	// Assume arguments are counted with the granularity of a single page,
	// so allow a one page cushion to account for rounding up
	long page_size = sysconf(_SC_PAGESIZE);
	if (page_size < 4096) {
		page_size = 4096;
	}
	arg_max -= page_size;
	bfs_exec_debug(execbuf, "ARG_MAX: %ld remaining after page cushion\n", arg_max);

	// POSIX recommends an additional 2048 bytes of headroom
	arg_max -= 2048;
	bfs_exec_debug(execbuf, "ARG_MAX: %ld remaining after headroom\n", arg_max);

	if (arg_max < 0) {
		arg_max = 0;
	} else if (arg_max > BFS_EXEC_ARG_MAX) {
		arg_max = BFS_EXEC_ARG_MAX;
	}

	bfs_exec_debug(execbuf, "ARG_MAX: %ld final value\n", arg_max);
	return arg_max;
}

/** Highlight part of the command line as an error. */
static void bfs_exec_parse_error(const struct bfs_ctx *ctx, const struct bfs_exec *execbuf) {
	char **argv = execbuf->tmpl_argv - 1;
	size_t argc = execbuf->tmpl_argc + 1;
	if (argv[argc]) {
		++argc;
	}

	bool args[ctx->argc];
	for (size_t i = 0; i < ctx->argc; ++i) {
		args[i] = false;
	}

	size_t i = argv - ctx->argv;
	for (size_t j = 0; j < argc; ++j) {
		args[i + j] = true;
	}

	bfs_argv_error(ctx, args);
}

struct bfs_exec *bfs_exec_parse(const struct bfs_ctx *ctx, char **argv, enum bfs_exec_flags flags) {
	struct bfs_exec *execbuf = ZALLOC(struct bfs_exec);
	if (!execbuf) {
		bfs_perror(ctx, "zalloc()");
		goto fail;
	}

	execbuf->flags = flags;
	execbuf->ctx = ctx;
	execbuf->tmpl_argv = argv + 1;
	execbuf->wd_fd = -1;

	while (true) {
		const char *arg = execbuf->tmpl_argv[execbuf->tmpl_argc];
		if (!arg) {
			if (execbuf->flags & BFS_EXEC_CONFIRM) {
				bfs_exec_parse_error(ctx, execbuf);
				bfs_error(ctx, "Expected '... ;'.\n");
			} else {
				bfs_exec_parse_error(ctx, execbuf);
				bfs_error(ctx, "Expected '... ;' or '... {} +'.\n");
			}
			goto fail;
		} else if (strcmp(arg, ";") == 0) {
			break;
		} else if (execbuf->tmpl_argc > 0 && strcmp(arg, "+") == 0) {
			const char *prev = execbuf->tmpl_argv[execbuf->tmpl_argc - 1];
			if (!(execbuf->flags & BFS_EXEC_CONFIRM) && strcmp(prev, "{}") == 0) {
				execbuf->flags |= BFS_EXEC_MULTI;
				break;
			}
		}

		++execbuf->tmpl_argc;
	}

	if (execbuf->tmpl_argc == 0) {
		bfs_exec_parse_error(ctx, execbuf);
		bfs_error(ctx, "Missing command.\n");
		goto fail;
	}

	execbuf->argv_cap = execbuf->tmpl_argc + 1;
	execbuf->argv = ALLOC_ARRAY(char *, execbuf->argv_cap);
	if (!execbuf->argv) {
		bfs_perror(ctx, "alloc()");
		goto fail;
	}

	if (execbuf->flags & BFS_EXEC_MULTI) {
		for (size_t i = 0; i < execbuf->tmpl_argc - 1; ++i) {
			char *arg = execbuf->tmpl_argv[i];
			if (strstr(arg, "{}")) {
				bfs_exec_parse_error(ctx, execbuf);
				bfs_error(ctx, "Only one '{}' is supported.\n");
				goto fail;
			}
			execbuf->argv[i] = arg;
		}
		execbuf->argc = execbuf->tmpl_argc - 1;

		execbuf->arg_max = bfs_exec_arg_max(execbuf);
		execbuf->arg_min = execbuf->arg_max;
	}

	return execbuf;

fail:
	bfs_exec_free(execbuf);
	return NULL;
}

/** Format the current path for use as a command line argument. */
static char *bfs_exec_format_path(const struct bfs_exec *execbuf, const struct BFTW *ftwbuf) {
	if (!(execbuf->flags & BFS_EXEC_CHDIR)) {
		return strdup(ftwbuf->path);
	}

	const char *name = ftwbuf->path + ftwbuf->nameoff;

	if (name[0] == '/') {
		// Must be a root path ("/", "//", etc.)
		return strdup(name);
	}

	// For compatibility with GNU find, use './name' instead of just 'name'
	char *path = malloc(2 + strlen(name) + 1);
	if (!path) {
		return NULL;
	}

	char *cur = stpcpy(path, "./");
	cur = stpcpy(cur, name);
	return path;
}

/** Format an argument, expanding "{}" to the current path. */
static char *bfs_exec_format_arg(char *arg, const char *path) {
	char *match = strstr(arg, "{}");
	if (!match) {
		return arg;
	}

	dchar *ret = dstralloc(0);
	if (!ret) {
		return NULL;
	}

	char *last = arg;
	do {
		if (dstrncat(&ret, last, match - last) != 0) {
			goto err;
		}
		if (dstrcat(&ret, path) != 0) {
			goto err;
		}

		last = match + 2;
		match = strstr(last, "{}");
	} while (match);

	if (dstrcat(&ret, last) != 0) {
		goto err;
	}

	return ret;

err:
	dstrfree(ret);
	return NULL;
}

/** Free a formatted argument. */
static void bfs_exec_free_arg(char *arg, const char *tmpl) {
	if (arg != tmpl) {
		dstrfree((dchar *)arg);
	}
}

/** Open a file to use as the working directory. */
static int bfs_exec_openwd(struct bfs_exec *execbuf, const struct BFTW *ftwbuf) {
	bfs_assert(execbuf->wd_fd < 0);
	bfs_assert(!execbuf->wd_path);

	if (ftwbuf->at_fd != AT_FDCWD) {
		// Rely on at_fd being the immediate parent
		bfs_assert(xbaseoff(ftwbuf->at_path) == 0);

		execbuf->wd_fd = ftwbuf->at_fd;
		if (!(execbuf->flags & BFS_EXEC_MULTI)) {
			return 0;
		}

		execbuf->wd_fd = dup_cloexec(execbuf->wd_fd);
		if (execbuf->wd_fd < 0) {
			return -1;
		}
	}

	execbuf->wd_len = ftwbuf->nameoff;
	if (execbuf->wd_len == 0) {
		if (ftwbuf->path[0] == '/') {
			++execbuf->wd_len;
		} else {
			// The path is something like "foo", so we're already in the right directory
			return 0;
		}
	}

	execbuf->wd_path = strndup(ftwbuf->path, execbuf->wd_len);
	if (!execbuf->wd_path) {
		return -1;
	}

	if (execbuf->wd_fd < 0) {
		execbuf->wd_fd = open(execbuf->wd_path, O_RDONLY | O_CLOEXEC | O_DIRECTORY);
	}

	if (execbuf->wd_fd < 0) {
		return -1;
	}

	return 0;
}

/** Close the working directory. */
static void bfs_exec_closewd(struct bfs_exec *execbuf, const struct BFTW *ftwbuf) {
	if (execbuf->wd_fd >= 0) {
		if (!ftwbuf || execbuf->wd_fd != ftwbuf->at_fd) {
			xclose(execbuf->wd_fd);
		}
		execbuf->wd_fd = -1;
	}

	if (execbuf->wd_path) {
		free(execbuf->wd_path);
		execbuf->wd_path = NULL;
		execbuf->wd_len = 0;
	}
}

/** Actually spawn the process. */
static int bfs_exec_spawn(const struct bfs_exec *execbuf) {
	const struct bfs_ctx *ctx = execbuf->ctx;

	// Flush the context state for consistency with the external process
	bfs_ctx_flush(ctx);

	if (execbuf->flags & BFS_EXEC_CONFIRM) {
		for (size_t i = 0; i < execbuf->argc; ++i) {
			if (fprintf(stderr, "%s ", execbuf->argv[i]) < 0) {
				return -1;
			}
		}
		if (fprintf(stderr, "? ") < 0) {
			return -1;
		}

		if (ynprompt() <= 0) {
			errno = 0;
			return -1;
		}
	}

	if (execbuf->flags & BFS_EXEC_MULTI) {
		bfs_exec_debug(execbuf, "Executing '%s' ... [%zu arguments] (size %zu)\n",
			execbuf->argv[0], execbuf->argc - 1, execbuf->arg_size);
	} else {
		bfs_exec_debug(execbuf, "Executing '%s' ... [%zu arguments]\n", execbuf->argv[0], execbuf->argc - 1);
	}

	pid_t pid = -1;
	int error;

	struct bfs_spawn spawn;
	if (bfs_spawn_init(&spawn) != 0) {
		return -1;
	}

	if (bfs_spawn_setflags(&spawn, BFS_SPAWN_USEPATH) != 0) {
		goto fail;
	}

	// Reset RLIMIT_NOFILE, to avoid breaking applications that use select()
	if (bfs_spawn_addsetrlimit(&spawn, RLIMIT_NOFILE, &ctx->orig_nofile) != 0) {
		goto fail;
	}

	if (execbuf->wd_fd >= 0) {
		if (bfs_spawn_addfchdir(&spawn, execbuf->wd_fd) != 0) {
			goto fail;
		}
	}

	pid = bfs_spawn(execbuf->argv[0], &spawn, execbuf->argv, NULL);
fail:
	error = errno;
	bfs_spawn_destroy(&spawn);
	if (pid < 0) {
		errno = error;
		return -1;
	}

	int wstatus;
	if (xwaitpid(pid, &wstatus, 0) < 0) {
		return -1;
	}

	int ret = -1;

	if (WIFEXITED(wstatus)) {
		int status = WEXITSTATUS(wstatus);
		if (status == EXIT_SUCCESS) {
			ret = 0;
		} else {
			bfs_exec_debug(execbuf, "Command '%s' failed with status %d\n", execbuf->argv[0], status);
		}
	} else if (WIFSIGNALED(wstatus)) {
		int sig = WTERMSIG(wstatus);
		const char *str = strsignal(sig);
		if (!str) {
			str = "unknown";
		}
		bfs_warning(ctx, "Command '${ex}%s${rs}' terminated by signal %d (%s)\n", execbuf->argv[0], sig, str);
	} else {
		bfs_warning(ctx, "Command '${ex}%s${rs}' terminated abnormally\n", execbuf->argv[0]);
	}

	errno = 0;
	return ret;
}

/** exec() a command for a single file. */
static int bfs_exec_single(struct bfs_exec *execbuf, const struct BFTW *ftwbuf) {
	int ret = -1, error = 0;

	char *path = bfs_exec_format_path(execbuf, ftwbuf);
	if (!path) {
		goto out;
	}

	size_t i;
	for (i = 0; i < execbuf->tmpl_argc; ++i) {
		execbuf->argv[i] = bfs_exec_format_arg(execbuf->tmpl_argv[i], path);
		if (!execbuf->argv[i]) {
			goto out_free;
		}
	}
	execbuf->argv[i] = NULL;
	execbuf->argc = i;

	if (execbuf->flags & BFS_EXEC_CHDIR) {
		if (bfs_exec_openwd(execbuf, ftwbuf) != 0) {
			goto out_free;
		}
	}

	ret = bfs_exec_spawn(execbuf);

out_free:
	error = errno;

	bfs_exec_closewd(execbuf, ftwbuf);

	for (size_t j = 0; j < i; ++j) {
		bfs_exec_free_arg(execbuf->argv[j], execbuf->tmpl_argv[j]);
	}

	free(path);

	errno = error;

out:
	return ret;
}

/** Check if any arguments remain in the buffer. */
static bool bfs_exec_args_remain(const struct bfs_exec *execbuf) {
	return execbuf->argc >= execbuf->tmpl_argc;
}

/** Compute the current ARG_MAX estimate for binary search. */
static size_t bfs_exec_estimate_max(const struct bfs_exec *execbuf) {
	size_t min = execbuf->arg_min;
	size_t max = execbuf->arg_max;
	return min + (max - min) / 2;
}

/** Update the ARG_MAX lower bound from a successful execution. */
static void bfs_exec_update_min(struct bfs_exec *execbuf) {
	if (execbuf->arg_size > execbuf->arg_min) {
		execbuf->arg_min = execbuf->arg_size;

		// Don't let min exceed max
		if (execbuf->arg_min > execbuf->arg_max) {
			execbuf->arg_min = execbuf->arg_max;
		}

		size_t estimate = bfs_exec_estimate_max(execbuf);
		bfs_exec_debug(execbuf, "ARG_MAX between [%zu, %zu], trying %zu\n",
			execbuf->arg_min, execbuf->arg_max, estimate);
	}
}

/** Update the ARG_MAX upper bound from a failed execution. */
static size_t bfs_exec_update_max(struct bfs_exec *execbuf) {
	bfs_exec_debug(execbuf, "Got E2BIG, shrinking argument list...\n");

	size_t size = execbuf->arg_size;
	if (size <= execbuf->arg_min) {
		// Lower bound was wrong, restart binary search.
		execbuf->arg_min = 0;
	}

	// Trim a fraction off the max size to avoid repeated failures near the
	// top end of the working range
	size -= size / 16;
	if (size < execbuf->arg_max) {
		execbuf->arg_max = size;

		// Don't let min exceed max
		if (execbuf->arg_min > execbuf->arg_max) {
			execbuf->arg_min = execbuf->arg_max;
		}
	}

	// Binary search for a more precise bound
	size_t estimate = bfs_exec_estimate_max(execbuf);
	bfs_exec_debug(execbuf, "ARG_MAX between [%zu, %zu], trying %zu\n",
		execbuf->arg_min, execbuf->arg_max, estimate);
	return estimate;
}

/** Execute the pending command from a BFS_EXEC_MULTI execbuf. */
static int bfs_exec_flush(struct bfs_exec *execbuf) {
	int ret = 0, error = 0;

	size_t orig_argc = execbuf->argc;
	while (bfs_exec_args_remain(execbuf)) {
		execbuf->argv[execbuf->argc] = NULL;
		ret = bfs_exec_spawn(execbuf);
		error = errno;
		if (ret == 0) {
			bfs_exec_update_min(execbuf);
			break;
		} else if (error != E2BIG) {
			break;
		}

		// Try to recover from E2BIG by trying fewer and fewer arguments
		// until they fit
		size_t new_max = bfs_exec_update_max(execbuf);
		while (execbuf->arg_size > new_max) {
			execbuf->argv[execbuf->argc] = execbuf->argv[execbuf->argc - 1];
			execbuf->arg_size -= bfs_exec_arg_size(execbuf->argv[execbuf->argc]);
			--execbuf->argc;
		}
	}

	size_t new_argc = execbuf->argc;
	for (size_t i = execbuf->tmpl_argc - 1; i < new_argc; ++i) {
		free(execbuf->argv[i]);
	}
	execbuf->argc = execbuf->tmpl_argc - 1;
	execbuf->arg_size = 0;

	if (new_argc < orig_argc) {
		// If we recovered from E2BIG, there are unused arguments at the
		// end of the list
		for (size_t i = new_argc + 1; i <= orig_argc; ++i) {
			if (error == 0) {
				execbuf->argv[execbuf->argc] = execbuf->argv[i];
				execbuf->arg_size += bfs_exec_arg_size(execbuf->argv[execbuf->argc]);
				++execbuf->argc;
			} else {
				free(execbuf->argv[i]);
			}
		}
	}

	errno = error;
	return ret;
}

/** Check if we need to flush the execbuf because we're changing directories. */
static bool bfs_exec_changed_dirs(const struct bfs_exec *execbuf, const struct BFTW *ftwbuf) {
	if (execbuf->flags & BFS_EXEC_CHDIR) {
		if (ftwbuf->nameoff > execbuf->wd_len
		    || (execbuf->wd_path && strncmp(ftwbuf->path, execbuf->wd_path, execbuf->wd_len) != 0)) {
			bfs_exec_debug(execbuf, "Changed directories, executing buffered command\n");
			return true;
		}
	}

	return false;
}

/** Check if we need to flush the execbuf because we're too big. */
static bool bfs_exec_would_overflow(const struct bfs_exec *execbuf, const char *arg) {
	size_t arg_max = bfs_exec_estimate_max(execbuf);
	size_t next_size = execbuf->arg_size + bfs_exec_arg_size(arg);
	if (next_size > arg_max) {
		bfs_exec_debug(execbuf, "Command size (%zu) would exceed maximum (%zu), executing buffered command\n",
			next_size, arg_max);
		return true;
	}

	return false;
}

/** Push a new argument to a BFS_EXEC_MULTI execbuf. */
static int bfs_exec_push(struct bfs_exec *execbuf, char *arg) {
	execbuf->argv[execbuf->argc] = arg;

	if (execbuf->argc + 1 >= execbuf->argv_cap) {
		size_t cap = 2 * execbuf->argv_cap;
		char **argv = realloc(execbuf->argv, sizeof_array(char *, cap));
		if (!argv) {
			return -1;
		}
		execbuf->argv = argv;
		execbuf->argv_cap = cap;
	}

	++execbuf->argc;
	execbuf->arg_size += bfs_exec_arg_size(arg);
	return 0;
}

/** Handle a new path for a BFS_EXEC_MULTI execbuf. */
static int bfs_exec_multi(struct bfs_exec *execbuf, const struct BFTW *ftwbuf) {
	int ret = 0;

	char *arg = bfs_exec_format_path(execbuf, ftwbuf);
	if (!arg) {
		ret = -1;
		goto out;
	}

	if (bfs_exec_changed_dirs(execbuf, ftwbuf)) {
		while (bfs_exec_args_remain(execbuf)) {
			ret |= bfs_exec_flush(execbuf);
		}
		bfs_exec_closewd(execbuf, ftwbuf);
	} else if (bfs_exec_would_overflow(execbuf, arg)) {
		ret |= bfs_exec_flush(execbuf);
	}

	if ((execbuf->flags & BFS_EXEC_CHDIR) && execbuf->wd_fd < 0) {
		if (bfs_exec_openwd(execbuf, ftwbuf) != 0) {
			ret = -1;
			goto out_arg;
		}
	}

	if (bfs_exec_push(execbuf, arg) != 0) {
		ret = -1;
		goto out_arg;
	}

	// arg will get cleaned up later by bfs_exec_flush()
	goto out;

out_arg:
	free(arg);
out:
	return ret;
}

int bfs_exec(struct bfs_exec *execbuf, const struct BFTW *ftwbuf) {
	if (execbuf->flags & BFS_EXEC_MULTI) {
		if (bfs_exec_multi(execbuf, ftwbuf) == 0) {
			errno = 0;
		} else {
			execbuf->ret = -1;
		}
		// -exec ... + never returns false
		return 0;
	} else {
		return bfs_exec_single(execbuf, ftwbuf);
	}
}

int bfs_exec_finish(struct bfs_exec *execbuf) {
	if (execbuf->flags & BFS_EXEC_MULTI) {
		bfs_exec_debug(execbuf, "Finishing execution, executing buffered command\n");
		while (bfs_exec_args_remain(execbuf)) {
			execbuf->ret |= bfs_exec_flush(execbuf);
		}
		if (execbuf->ret != 0) {
			bfs_exec_debug(execbuf, "One or more executions of '%s' failed\n", execbuf->argv[0]);
		}
	}
	return execbuf->ret;
}

void bfs_exec_free(struct bfs_exec *execbuf) {
	if (execbuf) {
		bfs_exec_closewd(execbuf, NULL);
		free(execbuf->argv);
		free(execbuf);
	}
}