Merge everything into one filesingle-file

1 files changed, 0 insertions, 3462 deletions

diff --git a/parse.c b/parse.c
deleted file mode 100644
index fbc987c..0000000
--- a/parse.c
+++ /dev/null
@@ -1,3462 +0,0 @@
-/****************************************************************************
- * bfs                                                                      *
- * Copyright (C) 2015-2019 Tavian Barnes <tavianator@tavianator.com>        *
- *                                                                          *
- * Permission to use, copy, modify, and/or distribute this software for any *
- * purpose with or without fee is hereby granted.                           *
- *                                                                          *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES *
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF         *
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR  *
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES   *
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN    *
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF  *
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.           *
- ****************************************************************************/
-
-/**
- * The command line parser.  Expressions are parsed by recursive descent, with a
- * grammar described in the comments of the parse_*() functions.  The parser
- * also accepts flags and paths at any point in the expression, by treating
- * flags like always-true options, and skipping over paths wherever they appear.
- */
-
-#include "bfs.h"
-#include "cmdline.h"
-#include "diag.h"
-#include "dstring.h"
-#include "eval.h"
-#include "exec.h"
-#include "expr.h"
-#include "fsade.h"
-#include "mtab.h"
-#include "printf.h"
-#include "spawn.h"
-#include "stat.h"
-#include "typo.h"
-#include "util.h"
-#include <assert.h>
-#include <ctype.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <fnmatch.h>
-#include <grp.h>
-#include <limits.h>
-#include <pwd.h>
-#include <regex.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/wait.h>
-#include <time.h>
-#include <unistd.h>
-
-// Strings printed by -D tree for "fake" expressions
-static char *fake_and_arg = "-a";
-static char *fake_false_arg = "-false";
-static char *fake_print_arg = "-print";
-static char *fake_true_arg = "-true";
-
-// Cost estimation constants
-#define FAST_COST     40.0
-#define STAT_COST   1000.0
-#define PRINT_COST 20000.0
-
-struct expr expr_true = {
-	.eval = eval_true,
-	.lhs = NULL,
-	.rhs = NULL,
-	.pure = true,
-	.always_true = true,
-	.cost = FAST_COST,
-	.probability = 1.0,
-	.argc = 1,
-	.argv = &fake_true_arg,
-};
-
-struct expr expr_false = {
-	.eval = eval_false,
-	.lhs = NULL,
-	.rhs = NULL,
-	.pure = true,
-	.always_false = true,
-	.cost = FAST_COST,
-	.probability = 0.0,
-	.argc = 1,
-	.argv = &fake_false_arg,
-};
-
-/**
- * Free an expression.
- */
-void free_expr(struct expr *expr) {
-	if (!expr || expr == &expr_true || expr == &expr_false) {
-		return;
-	}
-
-	if (expr->regex) {
-		regfree(expr->regex);
-		free(expr->regex);
-	}
-
-	free_bfs_printf(expr->printf);
-	free_bfs_exec(expr->execbuf);
-
-	free_expr(expr->lhs);
-	free_expr(expr->rhs);
-
-	free(expr);
-}
-
-struct expr *new_expr(eval_fn *eval, size_t argc, char **argv) {
-	struct expr *expr = malloc(sizeof(*expr));
-	if (!expr) {
-		perror("malloc()");
-		return NULL;
-	}
-
-	expr->eval = eval;
-	expr->lhs = NULL;
-	expr->rhs = NULL;
-	expr->pure = false;
-	expr->always_true = false;
-	expr->always_false = false;
-	expr->cost = FAST_COST;
-	expr->probability = 0.5;
-	expr->evaluations = 0;
-	expr->successes = 0;
-	expr->elapsed.tv_sec = 0;
-	expr->elapsed.tv_nsec = 0;
-	expr->argc = argc;
-	expr->argv = argv;
-	expr->cfile = NULL;
-	expr->regex = NULL;
-	expr->execbuf = NULL;
-	expr->printf = NULL;
-	expr->persistent_fds = 0;
-	expr->ephemeral_fds = 0;
-	return expr;
-}
-
-/**
- * Create a new unary expression.
- */
-static struct expr *new_unary_expr(eval_fn *eval, struct expr *rhs, char **argv) {
-	struct expr *expr = new_expr(eval, 1, argv);
-	if (!expr) {
-		free_expr(rhs);
-		return NULL;
-	}
-
-	expr->rhs = rhs;
-	expr->persistent_fds = rhs->persistent_fds;
-	expr->ephemeral_fds = rhs->ephemeral_fds;
-	return expr;
-}
-
-/**
- * Create a new binary expression.
- */
-static struct expr *new_binary_expr(eval_fn *eval, struct expr *lhs, struct expr *rhs, char **argv) {
-	struct expr *expr = new_expr(eval, 1, argv);
-	if (!expr) {
-		free_expr(rhs);
-		free_expr(lhs);
-		return NULL;
-	}
-
-	expr->lhs = lhs;
-	expr->rhs = rhs;
-	expr->persistent_fds = lhs->persistent_fds + rhs->persistent_fds;
-	if (lhs->ephemeral_fds > rhs->ephemeral_fds) {
-		expr->ephemeral_fds = lhs->ephemeral_fds;
-	} else {
-		expr->ephemeral_fds = rhs->ephemeral_fds;
-	}
-	return expr;
-}
-
-/**
- * Check if an expression never returns.
- */
-bool expr_never_returns(const struct expr *expr) {
-	// Expressions that never return are vacuously both always true and always false
-	return expr->always_true && expr->always_false;
-}
-
-/**
- * Set an expression to always return true.
- */
-static void expr_set_always_true(struct expr *expr) {
-	expr->always_true = true;
-	expr->probability = 1.0;
-}
-
-/**
- * Set an expression to never return.
- */
-static void expr_set_never_returns(struct expr *expr) {
-	expr->always_true = expr->always_false = true;
-}
-
-/**
- * Dump the parsed expression tree, for debugging.
- */
-void dump_expr(CFILE *cfile, const struct expr *expr, bool verbose) {
-	fputs("(", cfile->file);
-
-	if (expr->lhs || expr->rhs) {
-		cfprintf(cfile, "${red}%s${rs}", expr->argv[0]);
-	} else {
-		cfprintf(cfile, "${blu}%s${rs}", expr->argv[0]);
-	}
-
-	for (size_t i = 1; i < expr->argc; ++i) {
-		cfprintf(cfile, " ${bld}%s${rs}", expr->argv[i]);
-	}
-
-	if (verbose) {
-		double rate = 0.0, time = 0.0;
-		if (expr->evaluations) {
-			rate = 100.0*expr->successes/expr->evaluations;
-			time = (1.0e9*expr->elapsed.tv_sec + expr->elapsed.tv_nsec)/expr->evaluations;
-		}
-		cfprintf(cfile, " [${ylw}%zu${rs}/${ylw}%zu${rs}=${ylw}%g%%${rs}; ${ylw}%gns${rs}]", expr->successes, expr->evaluations, rate, time);
-	}
-
-	if (expr->lhs) {
-		fputs(" ", cfile->file);
-		dump_expr(cfile, expr->lhs, verbose);
-	}
-
-	if (expr->rhs) {
-		fputs(" ", cfile->file);
-		dump_expr(cfile, expr->rhs, verbose);
-	}
-
-	fputs(")", cfile->file);
-}
-
-/**
- * An open file for the command line.
- */
-struct open_file {
-	/** The file itself. */
-	CFILE *cfile;
-	/** The path to the file (for diagnostics). */
-	const char *path;
-};
-
-/**
- * Free the parsed command line.
- */
-int free_cmdline(struct cmdline *cmdline) {
-	int ret = 0;
-
-	if (cmdline) {
-		CFILE *cout = cmdline->cout;
-		CFILE *cerr = cmdline->cerr;
-
-		free_expr(cmdline->expr);
-
-		free_bfs_mtab(cmdline->mtab);
-
-		struct trie_leaf *leaf;
-		while ((leaf = trie_first_leaf(&cmdline->open_files))) {
-			struct open_file *ofile = leaf->value;
-
-			if (cfclose(ofile->cfile) != 0) {
-				if (cerr) {
-					bfs_error(cmdline, "'%s': %m.\n", ofile->path);
-				}
-				ret = -1;
-			}
-
-			free(ofile);
-			trie_remove(&cmdline->open_files, leaf);
-		}
-		trie_destroy(&cmdline->open_files);
-
-		if (cout && fflush(cout->file) != 0) {
-			if (cerr) {
-				bfs_error(cmdline, "standard output: %m.\n");
-			}
-			ret = -1;
-		}
-
-		cfclose(cout);
-		cfclose(cerr);
-
-		free_colors(cmdline->colors);
-		free(cmdline->paths);
-		free(cmdline->argv);
-		free(cmdline);
-	}
-
-	return ret;
-}
-
-/**
- * Color use flags.
- */
-enum use_color {
-	COLOR_NEVER,
-	COLOR_AUTO,
-	COLOR_ALWAYS,
-};
-
-/**
- * Ephemeral state for parsing the command line.
- */
-struct parser_state {
-	/** The command line being constructed. */
-	struct cmdline *cmdline;
-	/** The command line arguments being parsed. */
-	char **argv;
-	/** The name of this program. */
-	const char *command;
-
-	/** The current regex flags to use. */
-	int regex_flags;
-
-	/** Whether stdout is a terminal. */
-	bool stdout_tty;
-	/** Whether this session is interactive (stdin and stderr are each a terminal). */
-	bool interactive;
-	/** Whether -color or -nocolor has been passed. */
-	enum use_color use_color;
-	/** Whether a -print action is implied. */
-	bool implicit_print;
-	/** Whether warnings are enabled (see -warn, -nowarn). */
-	bool warn;
-	/** Whether the expression has started. */
-	bool expr_started;
-	/** Whether any non-option arguments have been encountered. */
-	bool non_option_seen;
-	/** Whether an information option like -help or -version was passed. */
-	bool just_info;
-
-	/** The last non-path argument. */
-	const char *last_arg;
-	/** A "-depth"-type argument if any. */
-	const char *depth_arg;
-	/** A "-prune"-type argument if any. */
-	const char *prune_arg;
-
-	/** The current time. */
-	struct timespec now;
-};
-
-/**
- * Possible token types.
- */
-enum token_type {
-	/** A flag. */
-	T_FLAG,
-	/** A root path. */
-	T_PATH,
-	/** An option. */
-	T_OPTION,
-	/** A test. */
-	T_TEST,
-	/** An action. */
-	T_ACTION,
-	/** An operator. */
-	T_OPERATOR,
-};
-
-/**
- * Print an error message during parsing.
- */
-BFS_FORMATTER(2, 3)
-static void parse_error(const struct parser_state *state, const char *format, ...) {
-	va_list args;
-	va_start(args, format);
-	bfs_verror(state->cmdline, format, args);
-	va_end(args);
-}
-
-/**
- * Print a warning message during parsing.
- */
-BFS_FORMATTER(2, 3)
-static void parse_warning(const struct parser_state *state, const char *format, ...) {
-	va_list args;
-	va_start(args, format);
-	bfs_vwarning(state->cmdline, format, args);
-	va_end(args);
-}
-
-/**
- * Fill in a "-print"-type expression.
- */
-static void init_print_expr(struct parser_state *state, struct expr *expr) {
-	expr_set_always_true(expr);
-	expr->cost = PRINT_COST;
-	expr->cfile = state->cmdline->cout;
-}
-
-/**
- * Open a file for an expression.
- */
-static int expr_open(struct parser_state *state, struct expr *expr, const char *path) {
-	int ret = -1;
-
-	struct cmdline *cmdline = state->cmdline;
-
-	CFILE *cfile = cfopen(path, state->use_color ? cmdline->colors : NULL);
-	if (!cfile) {
-		parse_error(state, "'%s': %m.\n", path);
-		goto out;
-	}
-
-	struct bfs_stat sb;
-	if (bfs_stat(fileno(cfile->file), NULL, 0, &sb) != 0) {
-		parse_error(state, "'%s': %m.\n", path);
-		goto out_close;
-	}
-
-	bfs_file_id id;
-	bfs_stat_id(&sb, &id);
-
-	struct trie_leaf *leaf = trie_insert_mem(&cmdline->open_files, id, sizeof(id));
-	if (leaf->value) {
-		struct open_file *ofile = leaf->value;
-		expr->cfile = ofile->cfile;
-		ret = 0;
-		goto out_close;
-	}
-
-	struct open_file *ofile = malloc(sizeof(*ofile));
-	if (!ofile) {
-		perror("malloc()");
-		trie_remove(&cmdline->open_files, leaf);
-		goto out_close;
-	}
-
-	ofile->cfile = cfile;
-	ofile->path = path;
-	leaf->value = ofile;
-	++cmdline->nopen_files;
-
-	expr->cfile = cfile;
-
-	ret = 0;
-	goto out;
-
-out_close:
-	cfclose(cfile);
-out:
-	return ret;
-}
-
-/**
- * Invoke bfs_stat() on an argument.
- */
-static int stat_arg(const struct parser_state *state, struct expr *expr, struct bfs_stat *sb) {
-	const struct cmdline *cmdline = state->cmdline;
-
-	bool follow = cmdline->flags & (BFTW_COMFOLLOW | BFTW_LOGICAL);
-	enum bfs_stat_flag flags = follow ? BFS_STAT_TRYFOLLOW : BFS_STAT_NOFOLLOW;
-
-	int ret = bfs_stat(AT_FDCWD, expr->sdata, flags, sb);
-	if (ret != 0) {
-		parse_error(state, "'%s': %m.\n", expr->sdata);
-	}
-	return ret;
-}
-
-/**
- * Parse the expression specified on the command line.
- */
-static struct expr *parse_expr(struct parser_state *state);
-
-/**
- * Advance by a single token.
- */
-static char **parser_advance(struct parser_state *state, enum token_type type, size_t argc) {
-	if (type != T_FLAG && type != T_PATH) {
-		state->expr_started = true;
-
-		if (type != T_OPTION) {
-			state->non_option_seen = true;
-		}
-	}
-
-	if (type != T_PATH) {
-		state->last_arg = *state->argv;
-	}
-
-	char **argv = state->argv;
-	state->argv += argc;
-	return argv;
-}
-
-/**
- * Parse a root path.
- */
-static int parse_root(struct parser_state *state, const char *path) {
-	struct cmdline *cmdline = state->cmdline;
-	size_t i = cmdline->npaths;
-	if ((i & (i + 1)) == 0) {
-		const char **paths = realloc(cmdline->paths, 2*(i + 1)*sizeof(*paths));
-		if (!paths) {
-			return -1;
-		}
-		cmdline->paths = paths;
-	}
-
-	cmdline->paths[i] = path;
-	cmdline->npaths = i + 1;
-	return 0;
-}
-
-/**
- * While parsing an expression, skip any paths and add them to the cmdline.
- */
-static int skip_paths(struct parser_state *state) {
-	while (true) {
-		const char *arg = state->argv[0];
-		if (!arg) {
-			return 0;
-		}
-
-		if (arg[0] == '-') {
-			if (strcmp(arg, "--") == 0) {
-				// find uses -- to separate flags from the rest
-				// of the command line.  We allow mixing flags
-				// and paths/predicates, so we just ignore --.
-				parser_advance(state, T_FLAG, 1);
-				continue;
-			}
-			if (strcmp(arg, "-") != 0) {
-				// - by itself is a file name.  Anything else
-				// starting with - is a flag/predicate.
-				return 0;
-			}
-		}
-
-		// By POSIX, these are always options
-		if (strcmp(arg, "(") == 0 || strcmp(arg, "!") == 0) {
-			return 0;
-		}
-
-		if (state->expr_started) {
-			// By POSIX, these can be paths.  We only treat them as
-			// such at the beginning of the command line.
-			if (strcmp(arg, ")") == 0 || strcmp(arg, ",") == 0) {
-				return 0;
-			}
-		}
-
-		if (parse_root(state, arg) != 0) {
-			return -1;
-		}
-
-		parser_advance(state, T_PATH, 1);
-	}
-}
-
-/** Integer parsing flags. */
-enum int_flags {
-	IF_BASE_MASK   = 0x03F,
-	IF_INT         = 0x040,
-	IF_LONG        = 0x080,
-	IF_LONG_LONG   = 0x0C0,
-	IF_SIZE_MASK   = 0x0C0,
-	IF_UNSIGNED    = 0x100,
-	IF_PARTIAL_OK  = 0x200,
-	IF_QUIET       = 0x400,
-};
-
-/**
- * Parse an integer.
- */
-static const char *parse_int(const struct parser_state *state, const char *str, void *result, enum int_flags flags) {
-	char *endptr;
-
-	int base = flags & IF_BASE_MASK;
-	if (base == 0) {
-		base = 10;
-	}
-
-	errno = 0;
-	long long value = strtoll(str, &endptr, base);
-	if (errno != 0) {
-		goto bad;
-	}
-
-	if (endptr == str) {
-		goto bad;
-	}
-
-	if (!(flags & IF_PARTIAL_OK) && *endptr != '\0') {
-		goto bad;
-	}
-
-	if ((flags & IF_UNSIGNED) && value < 0) {
-		goto bad;
-	}
-
-	switch (flags & IF_SIZE_MASK) {
-	case IF_INT:
-		if (value < INT_MIN || value > INT_MAX) {
-			goto bad;
-		}
-		*(int *)result = value;
-		break;
-
-	case IF_LONG:
-		if (value < LONG_MIN || value > LONG_MAX) {
-			goto bad;
-		}
-		*(long *)result = value;
-		break;
-
-	case IF_LONG_LONG:
-		*(long long *)result = value;
-		break;
-	}
-
-	return endptr;
-
-bad:
-	if (!(flags & IF_QUIET)) {
-		parse_error(state, "'%s' is not a valid integer.\n", str);
-	}
-	return NULL;
-}
-
-/**
- * Parse an integer and a comparison flag.
- */
-static const char *parse_icmp(const struct parser_state *state, const char *str, struct expr *expr, enum int_flags flags) {
-	switch (str[0]) {
-	case '-':
-		expr->cmp_flag = CMP_LESS;
-		++str;
-		break;
-	case '+':
-		expr->cmp_flag = CMP_GREATER;
-		++str;
-		break;
-	default:
-		expr->cmp_flag = CMP_EXACT;
-		break;
-	}
-
-	return parse_int(state, str, &expr->idata, flags | IF_LONG_LONG | IF_UNSIGNED);
-}
-
-/**
- * Check if a string could be an integer comparison.
- */
-static bool looks_like_icmp(const char *str) {
-	int i;
-
-	// One +/- for the comparison flag, one for the sign
-	for (i = 0; i < 2; ++i) {
-		if (str[i] != '-' && str[i] != '+') {
-			break;
-		}
-	}
-
-	return str[i] >= '0' && str[i] <= '9';
-}
-
-/**
- * Parse a single flag.
- */
-static struct expr *parse_flag(struct parser_state *state, size_t argc) {
-	parser_advance(state, T_FLAG, argc);
-	return &expr_true;
-}
-
-/**
- * Parse a flag that doesn't take a value.
- */
-static struct expr *parse_nullary_flag(struct parser_state *state) {
-	return parse_flag(state, 1);
-}
-
-/**
- * Parse a flag that takes a single value.
- */
-static struct expr *parse_unary_flag(struct parser_state *state) {
-	return parse_flag(state, 2);
-}
-
-/**
- * Parse a single option.
- */
-static struct expr *parse_option(struct parser_state *state, size_t argc) {
-	const char *arg = *parser_advance(state, T_OPTION, argc);
-
-	if (state->warn && state->non_option_seen) {
-		parse_warning(state,
-		              "The '%s' option applies to the entire command line.  For clarity, place\n"
-		              "it before any non-option arguments.\n\n",
-		              arg);
-	}
-
-
-	return &expr_true;
-}
-
-/**
- * Parse an option that doesn't take a value.
- */
-static struct expr *parse_nullary_option(struct parser_state *state) {
-	return parse_option(state, 1);
-}
-
-/**
- * Parse an option that takes a value.
- */
-static struct expr *parse_unary_option(struct parser_state *state) {
-	return parse_option(state, 2);
-}
-
-/**
- * Parse a single positional option.
- */
-static struct expr *parse_positional_option(struct parser_state *state, size_t argc) {
-	parser_advance(state, T_OPTION, argc);
-	return &expr_true;
-}
-
-/**
- * Parse a positional option that doesn't take a value.
- */
-static struct expr *parse_nullary_positional_option(struct parser_state *state) {
-	return parse_positional_option(state, 1);
-}
-
-/**
- * Parse a positional option that takes a single value.
- */
-static struct expr *parse_unary_positional_option(struct parser_state *state, const char **value) {
-	const char *arg = state->argv[0];
-	*value = state->argv[1];
-	if (!*value) {
-		parse_error(state, "%s needs a value.\n", arg);
-		return NULL;
-	}
-
-	return parse_positional_option(state, 2);
-}
-
-/**
- * Parse a single test.
- */
-static struct expr *parse_test(struct parser_state *state, eval_fn *eval, size_t argc) {
-	char **argv = parser_advance(state, T_TEST, argc);
-	struct expr *expr = new_expr(eval, argc, argv);
-	if (expr) {
-		expr->pure = true;
-	}
-	return expr;
-}
-
-/**
- * Parse a test that doesn't take a value.
- */
-static struct expr *parse_nullary_test(struct parser_state *state, eval_fn *eval) {
-	return parse_test(state, eval, 1);
-}
-
-/**
- * Parse a test that takes a value.
- */
-static struct expr *parse_unary_test(struct parser_state *state, eval_fn *eval) {
-	const char *arg = state->argv[0];
-	const char *value = state->argv[1];
-	if (!value) {
-		parse_error(state, "%s needs a value.\n", arg);
-		return NULL;
-	}
-
-	struct expr *expr = parse_test(state, eval, 2);
-	if (expr) {
-		expr->sdata = value;
-	}
-	return expr;
-}
-
-/**
- * Parse a single action.
- */
-static struct expr *parse_action(struct parser_state *state, eval_fn *eval, size_t argc) {
-	if (eval != eval_nohidden && eval != eval_prune && eval != eval_quit) {
-		state->implicit_print = false;
-	}
-
-	char **argv = parser_advance(state, T_ACTION, argc);
-	return new_expr(eval, argc, argv);
-}
-
-/**
- * Parse an action that takes no arguments.
- */
-static struct expr *parse_nullary_action(struct parser_state *state, eval_fn *eval) {
-	return parse_action(state, eval, 1);
-}
-
-/**
- * Parse an action that takes one argument.
- */
-static struct expr *parse_unary_action(struct parser_state *state, eval_fn *eval) {
-	const char *arg = state->argv[0];
-	const char *value = state->argv[1];
-	if (!value) {
-		parse_error(state, "%s needs a value.\n", arg);
-		return NULL;
-	}
-
-	struct expr *expr = parse_action(state, eval, 2);
-	if (expr) {
-		expr->sdata = value;
-	}
-	return expr;
-}
-
-/**
- * Parse a test expression with integer data and a comparison flag.
- */
-static struct expr *parse_test_icmp(struct parser_state *state, eval_fn *eval) {
-	struct expr *expr = parse_unary_test(state, eval);
-	if (!expr) {
-		return NULL;
-	}
-
-	if (!parse_icmp(state, expr->sdata, expr, 0)) {
-		free_expr(expr);
-		return NULL;
-	}
-
-	return expr;
-}
-
-/**
- * Print usage information for -D.
- */
-static void debug_help(CFILE *cfile) {
-	cfprintf(cfile, "Supported debug flags:\n\n");
-
-	cfprintf(cfile, "  ${bld}help${rs}:   This message.\n");
-	cfprintf(cfile, "  ${bld}cost${rs}:   Show cost estimates.\n");
-	cfprintf(cfile, "  ${bld}exec${rs}:   Print executed command details.\n");
-	cfprintf(cfile, "  ${bld}opt${rs}:    Print optimization details.\n");
-	cfprintf(cfile, "  ${bld}rates${rs}:  Print predicate success rates.\n");
-	cfprintf(cfile, "  ${bld}search${rs}: Trace the filesystem traversal.\n");
-	cfprintf(cfile, "  ${bld}stat${rs}:   Trace all stat() calls.\n");
-	cfprintf(cfile, "  ${bld}tree${rs}:   Print the parse tree.\n");
-	cfprintf(cfile, "  ${bld}all${rs}:    All debug flags at once.\n");
-}
-
-/** A named debug flag. */
-struct debug_flag {
-	enum debug_flags flag;
-	const char *name;
-};
-
-/** The table of debug flags. */
-struct debug_flag debug_flags[] = {
-	{DEBUG_ALL,    "all"},
-	{DEBUG_COST,   "cost"},
-	{DEBUG_EXEC,   "exec"},
-	{DEBUG_OPT,    "opt"},
-	{DEBUG_RATES,  "rates"},
-	{DEBUG_SEARCH, "search"},
-	{DEBUG_STAT,   "stat"},
-	{DEBUG_TREE,   "tree"},
-	{0},
-};
-
-/** Check if a substring matches a debug flag. */
-static bool parse_debug_flag(const char *flag, size_t len, const char *expected) {
-	if (len == strlen(expected)) {
-		return strncmp(flag, expected, len) == 0;
-	} else {
-		return false;
-	}
-}
-
-/**
- * Parse -D FLAG.
- */
-static struct expr *parse_debug(struct parser_state *state, int arg1, int arg2) {
-	struct cmdline *cmdline = state->cmdline;
-
-	const char *arg = state->argv[0];
-	const char *flags = state->argv[1];
-	if (!flags) {
-		parse_error(state, "%s needs a flag.\n\n", arg);
-		debug_help(cmdline->cerr);
-		return NULL;
-	}
-
-	bool unrecognized = false;
-
-	for (const char *flag = flags, *next; flag; flag = next) {
-		size_t len = strcspn(flag, ",");
-		if (flag[len]) {
-			next = flag + len + 1;
-		} else {
-			next = NULL;
-		}
-
-		if (parse_debug_flag(flag, len, "help")) {
-			debug_help(cmdline->cout);
-			state->just_info = true;
-			return NULL;
-		}
-
-		for (int i = 0; ; ++i) {
-			const char *expected = debug_flags[i].name;
-			if (!expected) {
-				parse_warning(state, "Unrecognized debug flag '");
-				fwrite(flag, 1, len, stderr);
-				fputs("'\n\n", stderr);
-				unrecognized = true;
-				break;
-			}
-
-			if (parse_debug_flag(flag, len, expected)) {
-				cmdline->debug |= debug_flags[i].flag;
-				break;
-			}
-		}
-	}
-
-	if (unrecognized) {
-		debug_help(cmdline->cerr);
-		cfprintf(cmdline->cerr, "\n");
-	}
-
-	return parse_unary_flag(state);
-}
-
-/**
- * Parse -On.
- */
-static struct expr *parse_optlevel(struct parser_state *state, int arg1, int arg2) {
-	int *optlevel = &state->cmdline->optlevel;
-
-	if (strcmp(state->argv[0], "-Ofast") == 0) {
-		*optlevel = 4;
-	} else if (!parse_int(state, state->argv[0] + 2, optlevel, IF_INT | IF_UNSIGNED)) {
-		return NULL;
-	}
-
-	if (state->warn && *optlevel > 4) {
-		parse_warning(state, "%s is the same as -O4.\n\n", state->argv[0]);
-	}
-
-	return parse_nullary_flag(state);
-}
-
-/**
- * Parse -[PHL], -(no)?follow.
- */
-static struct expr *parse_follow(struct parser_state *state, int flags, int option) {
-	struct cmdline *cmdline = state->cmdline;
-	cmdline->flags &= ~(BFTW_COMFOLLOW | BFTW_LOGICAL);
-	cmdline->flags |= flags;
-	if (option) {
-		return parse_nullary_positional_option(state);
-	} else {
-		return parse_nullary_flag(state);
-	}
-}
-
-/**
- * Parse -X.
- */
-static struct expr *parse_xargs_safe(struct parser_state *state, int arg1, int arg2) {
-	state->cmdline->xargs_safe = true;
-	return parse_nullary_flag(state);
-}
-
-/**
- * Parse -executable, -readable, -writable
- */
-static struct expr *parse_access(struct parser_state *state, int flag, int arg2) {
-	struct expr *expr = parse_nullary_test(state, eval_access);
-	if (!expr) {
-		return NULL;
-	}
-
-	expr->idata = flag;
-	expr->cost = STAT_COST;
-
-	switch (flag) {
-	case R_OK:
-		expr->probability = 0.99;
-		break;
-	case W_OK:
-		expr->probability = 0.8;
-		break;
-	case X_OK:
-		expr->probability = 0.2;
-		break;
-	}
-
-	return expr;
-}
-
-/**
- * Parse -acl.
- */
-static struct expr *parse_acl(struct parser_state *state, int flag, int arg2) {
-#if BFS_CAN_CHECK_ACL
-	struct expr *expr = parse_nullary_test(state, eval_acl);
-	if (expr) {
-		expr->cost = STAT_COST;
-		expr->probability = 0.00002;
-	}
-	return expr;
-#else
-	parse_error(state, "%s is missing platform support.\n", state->argv[0]);
-	return NULL;
-#endif
-}
-
-/**
- * Parse -[aBcm]?newer.
- */
-static struct expr *parse_newer(struct parser_state *state, int field, int arg2) {
-	struct expr *expr = parse_unary_test(state, eval_newer);
-	if (!expr) {
-		return NULL;
-	}
-
-	struct bfs_stat sb;
-	if (stat_arg(state, expr, &sb) != 0) {
-		goto fail;
-	}
-
-	expr->cost = STAT_COST;
-	expr->reftime = sb.mtime;
-	expr->stat_field = field;
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -[aBcm]{min,time}.
- */
-static struct expr *parse_time(struct parser_state *state, int field, int unit) {
-	struct expr *expr = parse_test_icmp(state, eval_time);
-	if (!expr) {
-		return NULL;
-	}
-
-	expr->cost = STAT_COST;
-	expr->reftime = state->now;
-	expr->stat_field = field;
-	expr->time_unit = unit;
-	return expr;
-}
-
-/**
- * Parse -capable.
- */
-static struct expr *parse_capable(struct parser_state *state, int flag, int arg2) {
-#if BFS_CAN_CHECK_CAPABILITIES
-	struct expr *expr = parse_nullary_test(state, eval_capable);
-	if (expr) {
-		expr->cost = STAT_COST;
-		expr->probability = 0.000002;
-	}
-	return expr;
-#else
-	parse_error(state, "%s is missing platform support.\n", state->argv[0]);
-	return NULL;
-#endif
-}
-
-/**
- * Parse -(no)?color.
- */
-static struct expr *parse_color(struct parser_state *state, int color, int arg2) {
-	struct cmdline *cmdline = state->cmdline;
-	struct colors *colors = cmdline->colors;
-	if (color) {
-		state->use_color = COLOR_ALWAYS;
-		cmdline->cout->colors = colors;
-		cmdline->cerr->colors = colors;
-	} else {
-		state->use_color = COLOR_NEVER;
-		cmdline->cout->colors = NULL;
-		cmdline->cerr->colors = NULL;
-	}
-	return parse_nullary_option(state);
-}
-
-/**
- * Parse -{false,true}.
- */
-static struct expr *parse_const(struct parser_state *state, int value, int arg2) {
-	parser_advance(state, T_TEST, 1);
-	return value ? &expr_true : &expr_false;
-}
-
-/**
- * Parse -daystart.
- */
-static struct expr *parse_daystart(struct parser_state *state, int arg1, int arg2) {
-	struct tm tm;
-	if (xlocaltime(&state->now.tv_sec, &tm) != 0) {
-		perror("xlocaltime()");
-		return NULL;
-	}
-
-	if (tm.tm_hour || tm.tm_min || tm.tm_sec || state->now.tv_nsec) {
-		++tm.tm_mday;
-	}
-	tm.tm_hour = 0;
-	tm.tm_min = 0;
-	tm.tm_sec = 0;
-
-	time_t time = mktime(&tm);
-	if (time == -1) {
-		perror("mktime()");
-		return NULL;
-	}
-
-	state->now.tv_sec = time;
-	state->now.tv_nsec = 0;
-
-	return parse_nullary_positional_option(state);
-}
-
-/**
- * Parse -delete.
- */
-static struct expr *parse_delete(struct parser_state *state, int arg1, int arg2) {
-	state->cmdline->flags |= BFTW_DEPTH;
-	state->depth_arg = state->argv[0];
-	return parse_nullary_action(state, eval_delete);
-}
-
-/**
- * Parse -d.
- */
-static struct expr *parse_depth(struct parser_state *state, int arg1, int arg2) {
-	state->cmdline->flags |= BFTW_DEPTH;
-	state->depth_arg = state->argv[0];
-	return parse_nullary_flag(state);
-}
-
-/**
- * Parse -depth [N].
- */
-static struct expr *parse_depth_n(struct parser_state *state, int arg1, int arg2) {
-	const char *arg = state->argv[1];
-	if (arg && looks_like_icmp(arg)) {
-		return parse_test_icmp(state, eval_depth);
-	} else {
-		return parse_depth(state, arg1, arg2);
-	}
-}
-
-/**
- * Parse -{min,max}depth N.
- */
-static struct expr *parse_depth_limit(struct parser_state *state, int is_min, int arg2) {
-	struct cmdline *cmdline = state->cmdline;
-	const char *arg = state->argv[0];
-	const char *value = state->argv[1];
-	if (!value) {
-		parse_error(state, "%s needs a value.\n", arg);
-		return NULL;
-	}
-
-	int *depth = is_min ? &cmdline->mindepth : &cmdline->maxdepth;
-	if (!parse_int(state, value, depth, IF_INT | IF_UNSIGNED)) {
-		return NULL;
-	}
-
-	return parse_unary_option(state);
-}
-
-/**
- * Parse -empty.
- */
-static struct expr *parse_empty(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_nullary_test(state, eval_empty);
-	if (!expr) {
-		return NULL;
-	}
-
-	expr->cost = 2000.0;
-	expr->probability = 0.01;
-
-	if (state->cmdline->optlevel < 4) {
-		// Since -empty attempts to open and read directories, it may
-		// have side effects such as reporting permission errors, and
-		// thus shouldn't be re-ordered without aggressive optimizations
-		expr->pure = false;
-	}
-
-	expr->ephemeral_fds = 1;
-
-	return expr;
-}
-
-/**
- * Parse -exec(dir)?/-ok(dir)?.
- */
-static struct expr *parse_exec(struct parser_state *state, int flags, int arg2) {
-	struct bfs_exec *execbuf = parse_bfs_exec(state->argv, flags, state->cmdline);
-	if (!execbuf) {
-		return NULL;
-	}
-
-	struct expr *expr = parse_action(state, eval_exec, execbuf->tmpl_argc + 2);
-	if (!expr) {
-		free_bfs_exec(execbuf);
-		return NULL;
-	}
-
-	expr->execbuf = execbuf;
-
-	if (execbuf->flags & BFS_EXEC_MULTI) {
-		expr_set_always_true(expr);
-	} else {
-		expr->cost = 1000000.0;
-	}
-
-	expr->ephemeral_fds = 2;
-	if (execbuf->flags & BFS_EXEC_CHDIR) {
-		if (execbuf->flags & BFS_EXEC_MULTI) {
-			expr->persistent_fds = 1;
-		} else {
-			++expr->ephemeral_fds;
-		}
-	}
-
-	return expr;
-}
-
-/**
- * Parse -exit [STATUS].
- */
-static struct expr *parse_exit(struct parser_state *state, int arg1, int arg2) {
-	size_t argc = 1;
-	const char *value = state->argv[1];
-
-	int status = EXIT_SUCCESS;
-	if (value && parse_int(state, value, &status, IF_INT | IF_UNSIGNED | IF_QUIET)) {
-		argc = 2;
-	}
-
-	struct expr *expr = parse_action(state, eval_exit, argc);
-	if (expr) {
-		expr_set_never_returns(expr);
-		expr->idata = status;
-	}
-	return expr;
-}
-
-/**
- * Parse -f PATH.
- */
-static struct expr *parse_f(struct parser_state *state, int arg1, int arg2) {
-	parser_advance(state, T_FLAG, 1);
-
-	const char *path = state->argv[0];
-	if (!path) {
-		parse_error(state, "-f requires a path.\n");
-		return NULL;
-	}
-
-	if (parse_root(state, path) != 0) {
-		return NULL;
-	}
-
-	parser_advance(state, T_PATH, 1);
-	return &expr_true;
-}
-
-/**
- * Parse -fls FILE.
- */
-static struct expr *parse_fls(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_unary_action(state, eval_fls);
-	if (expr) {
-		expr_set_always_true(expr);
-		expr->cost = PRINT_COST;
-		if (expr_open(state, expr, expr->sdata) != 0) {
-			goto fail;
-		}
-		expr->reftime = state->now;
-	}
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -fprint FILE.
- */
-static struct expr *parse_fprint(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_unary_action(state, eval_fprint);
-	if (expr) {
-		expr_set_always_true(expr);
-		expr->cost = PRINT_COST;
-		if (expr_open(state, expr, expr->sdata) != 0) {
-			goto fail;
-		}
-	}
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -fprint0 FILE.
- */
-static struct expr *parse_fprint0(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_unary_action(state, eval_fprint0);
-	if (expr) {
-		expr_set_always_true(expr);
-		expr->cost = PRINT_COST;
-		if (expr_open(state, expr, expr->sdata) != 0) {
-			goto fail;
-		}
-	}
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -fprintf FILE FORMAT.
- */
-static struct expr *parse_fprintf(struct parser_state *state, int arg1, int arg2) {
-	const char *arg = state->argv[0];
-
-	const char *file = state->argv[1];
-	if (!file) {
-		parse_error(state, "%s needs a file.\n", arg);
-		return NULL;
-	}
-
-	const char *format = state->argv[2];
-	if (!format) {
-		parse_error(state, "%s needs a format string.\n", arg);
-		return NULL;
-	}
-
-	struct expr *expr = parse_action(state, eval_fprintf, 3);
-	if (!expr) {
-		return NULL;
-	}
-
-	expr_set_always_true(expr);
-
-	expr->cost = PRINT_COST;
-
-	if (expr_open(state, expr, file) != 0) {
-		goto fail;
-	}
-
-	expr->printf = parse_bfs_printf(format, state->cmdline);
-	if (!expr->printf) {
-		goto fail;
-	}
-
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -fstype TYPE.
- */
-static struct expr *parse_fstype(struct parser_state *state, int arg1, int arg2) {
-	struct cmdline *cmdline = state->cmdline;
-	if (!cmdline->mtab) {
-		parse_error(state, "Couldn't parse the mount table: %s.\n", strerror(cmdline->mtab_error));
-		return NULL;
-	}
-
-	struct expr *expr = parse_unary_test(state, eval_fstype);
-	if (expr) {
-		expr->cost = STAT_COST;
-	}
-	return expr;
-}
-
-/**
- * Parse -gid/-group.
- */
-static struct expr *parse_group(struct parser_state *state, int arg1, int arg2) {
-	const char *arg = state->argv[0];
-
-	struct expr *expr = parse_unary_test(state, eval_gid);
-	if (!expr) {
-		return NULL;
-	}
-
-	struct group *grp = getgrnam(expr->sdata);
-	if (grp) {
-		expr->idata = grp->gr_gid;
-		expr->cmp_flag = CMP_EXACT;
-	} else if (looks_like_icmp(expr->sdata)) {
-		if (!parse_icmp(state, expr->sdata, expr, 0)) {
-			goto fail;
-		}
-	} else {
-		parse_error(state, "%s %s: No such group.\n", arg, expr->sdata);
-		goto fail;
-	}
-
-	expr->cost = STAT_COST;
-
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -unique.
- */
-static struct expr *parse_unique(struct parser_state *state, int arg1, int arg2) {
-	state->cmdline->unique = true;
-	return parse_nullary_option(state);
-}
-
-/**
- * Parse -used N.
- */
-static struct expr *parse_used(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_test_icmp(state, eval_used);
-	if (expr) {
-		expr->cost = STAT_COST;
-	}
-	return expr;
-}
-
-/**
- * Parse -uid/-user.
- */
-static struct expr *parse_user(struct parser_state *state, int arg1, int arg2) {
-	const char *arg = state->argv[0];
-
-	struct expr *expr = parse_unary_test(state, eval_uid);
-	if (!expr) {
-		return NULL;
-	}
-
-	struct passwd *pwd = getpwnam(expr->sdata);
-	if (pwd) {
-		expr->idata = pwd->pw_uid;
-		expr->cmp_flag = CMP_EXACT;
-	} else if (looks_like_icmp(expr->sdata)) {
-		if (!parse_icmp(state, expr->sdata, expr, 0)) {
-			goto fail;
-		}
-	} else {
-		parse_error(state, "%s %s: No such user.\n", arg, expr->sdata);
-		goto fail;
-	}
-
-	expr->cost = STAT_COST;
-
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -hidden.
- */
-static struct expr *parse_hidden(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_nullary_test(state, eval_hidden);
-	if (expr) {
-		expr->probability = 0.01;
-	}
-	return expr;
-}
-
-/**
- * Parse -(no)?ignore_readdir_race.
- */
-static struct expr *parse_ignore_races(struct parser_state *state, int ignore, int arg2) {
-	state->cmdline->ignore_races = ignore;
-	return parse_nullary_option(state);
-}
-
-/**
- * Parse -inum N.
- */
-static struct expr *parse_inum(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_test_icmp(state, eval_inum);
-	if (expr) {
-		expr->cost = STAT_COST;
-		expr->probability = expr->cmp_flag == CMP_EXACT ? 0.01 : 0.50;
-	}
-	return expr;
-}
-
-/**
- * Parse -links N.
- */
-static struct expr *parse_links(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_test_icmp(state, eval_links);
-	if (expr) {
-		expr->cost = STAT_COST;
-		expr->probability = expr_cmp(expr, 1) ? 0.99 : 0.01;
-	}
-	return expr;
-}
-
-/**
- * Parse -ls.
- */
-static struct expr *parse_ls(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_nullary_action(state, eval_fls);
-	if (expr) {
-		init_print_expr(state, expr);
-		expr->reftime = state->now;
-	}
-	return expr;
-}
-
-/**
- * Parse -mount, -xdev.
- */
-static struct expr *parse_mount(struct parser_state *state, int arg1, int arg2) {
-	state->cmdline->flags |= BFTW_XDEV;
-	return parse_nullary_option(state);
-}
-
-/**
- * Common code for fnmatch() tests.
- */
-static struct expr *parse_fnmatch(const struct parser_state *state, struct expr *expr, bool casefold) {
-	if (!expr) {
-		return NULL;
-	}
-
-	if (casefold) {
-#ifdef FNM_CASEFOLD
-		expr->idata = FNM_CASEFOLD;
-#else
-		parse_error(state, "%s is missing platform support.\n", expr->argv[0]);
-		free_expr(expr);
-		return NULL;
-#endif
-	} else {
-		expr->idata = 0;
-	}
-
-	expr->cost = 400.0;
-
-	if (strchr(expr->sdata, '*')) {
-		expr->probability = 0.5;
-	} else {
-		expr->probability = 0.1;
-	}
-
-	return expr;
-}
-
-/**
- * Parse -i?name.
- */
-static struct expr *parse_name(struct parser_state *state, int casefold, int arg2) {
-	struct expr *expr = parse_unary_test(state, eval_name);
-	return parse_fnmatch(state, expr, casefold);
-}
-
-/**
- * Parse -i?path, -i?wholename.
- */
-static struct expr *parse_path(struct parser_state *state, int casefold, int arg2) {
-	struct expr *expr = parse_unary_test(state, eval_path);
-	return parse_fnmatch(state, expr, casefold);
-}
-
-/**
- * Parse -i?lname.
- */
-static struct expr *parse_lname(struct parser_state *state, int casefold, int arg2) {
-	struct expr *expr = parse_unary_test(state, eval_lname);
-	return parse_fnmatch(state, expr, casefold);
-}
-
-/** Get the bfs_stat_field for X/Y in -newerXY */
-static enum bfs_stat_field parse_newerxy_field(char c) {
-	switch (c) {
-	case 'a':
-		return BFS_STAT_ATIME;
-	case 'B':
-		return BFS_STAT_BTIME;
-	case 'c':
-		return BFS_STAT_CTIME;
-	case 'm':
-		return BFS_STAT_MTIME;
-	default:
-		return 0;
-	}
-}
-
-/**
- * Parse -newerXY.
- */
-static struct expr *parse_newerxy(struct parser_state *state, int arg1, int arg2) {
-	const char *arg = state->argv[0];
-	if (strlen(arg) != 8) {
-		parse_error(state, "Expected -newerXY; found %s.\n", arg);
-		return NULL;
-	}
-
-	struct expr *expr = parse_unary_test(state, eval_newer);
-	if (!expr) {
-		goto fail;
-	}
-
-	expr->stat_field = parse_newerxy_field(arg[6]);
-	if (!expr->stat_field) {
-		parse_error(state, "%s: For -newerXY, X should be 'a', 'c', 'm', or 'B'.\n", arg);
-		goto fail;
-	}
-
-	if (arg[7] == 't') {
-		parse_error(state, "%s: Explicit reference times ('t') are not supported.\n", arg);
-		goto fail;
-	} else {
-		enum bfs_stat_field field = parse_newerxy_field(arg[7]);
-		if (!field) {
-			parse_error(state, "%s: For -newerXY, Y should be 'a', 'c', 'm', 'B', or 't'.\n", arg);
-			goto fail;
-		}
-
-		struct bfs_stat sb;
-		if (stat_arg(state, expr, &sb) != 0) {
-			goto fail;
-		}
-
-
-		const struct timespec *reftime = bfs_stat_time(&sb, field);
-		if (!reftime) {
-			parse_error(state, "'%s': Couldn't get file %s.\n", expr->sdata, bfs_stat_field_name(field));
-			goto fail;
-		}
-
-		expr->reftime = *reftime;
-	}
-
-	expr->cost = STAT_COST;
-
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -nogroup.
- */
-static struct expr *parse_nogroup(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_nullary_test(state, eval_nogroup);
-	if (expr) {
-		expr->cost = 9000.0;
-		expr->probability = 0.01;
-		expr->ephemeral_fds = 1;
-	}
-	return expr;
-}
-
-/**
- * Parse -nohidden.
- */
-static struct expr *parse_nohidden(struct parser_state *state, int arg1, int arg2) {
-	state->prune_arg = state->argv[0];
-	return parse_nullary_action(state, eval_nohidden);
-}
-
-/**
- * Parse -noleaf.
- */
-static struct expr *parse_noleaf(struct parser_state *state, int arg1, int arg2) {
-	if (state->warn) {
-		parse_warning(state, "bfs does not apply the optimization that %s inhibits.\n\n", state->argv[0]);
-	}
-
-	return parse_nullary_option(state);
-}
-
-/**
- * Parse -nouser.
- */
-static struct expr *parse_nouser(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_nullary_test(state, eval_nouser);
-	if (expr) {
-		expr->cost = 9000.0;
-		expr->probability = 0.01;
-		expr->ephemeral_fds = 1;
-	}
-	return expr;
-}
-
-/**
- * Parse a permission mode like chmod(1).
- */
-static int parse_mode(const struct parser_state *state, const char *mode, struct expr *expr) {
-	if (mode[0] >= '0' && mode[0] <= '9') {
-		unsigned int parsed;
-		if (!parse_int(state, mode, &parsed, 8 | IF_INT | IF_UNSIGNED | IF_QUIET)) {
-			goto fail;
-		}
-		if (parsed > 07777) {
-			goto fail;
-		}
-
-		expr->file_mode = parsed;
-		expr->dir_mode = parsed;
-		return 0;
-	}
-
-	expr->file_mode = 0;
-	expr->dir_mode = 0;
-
-	// Parse the same grammar as chmod(1), which looks like this:
-	//
-	// MODE : CLAUSE ["," CLAUSE]*
-	//
-	// CLAUSE : WHO* ACTION+
-	//
-	// WHO : "u" | "g" | "o" | "a"
-	//
-	// ACTION : OP PERM*
-	//        | OP PERMCOPY
-	//
-	// OP : "+" | "-" | "="
-	//
-	// PERM : "r" | "w" | "x" | "X" | "s" | "t"
-	//
-	// PERMCOPY : "u" | "g" | "o"
-
-	// State machine state
-	enum {
-		MODE_CLAUSE,
-		MODE_WHO,
-		MODE_ACTION,
-		MODE_ACTION_APPLY,
-		MODE_OP,
-		MODE_PERM,
-	} mstate = MODE_CLAUSE;
-
-	enum {
-		MODE_PLUS,
-		MODE_MINUS,
-		MODE_EQUALS,
-	} op;
-
-	mode_t who;
-	mode_t file_change;
-	mode_t dir_change;
-
-	const char *i = mode;
-	while (true) {
-		switch (mstate) {
-		case MODE_CLAUSE:
-			who = 0;
-			mstate = MODE_WHO;
-			// Fallthrough
-
-		case MODE_WHO:
-			switch (*i) {
-			case 'u':
-				who |= 0700;
-				break;
-			case 'g':
-				who |= 0070;
-				break;
-			case 'o':
-				who |= 0007;
-				break;
-			case 'a':
-				who |= 0777;
-				break;
-			default:
-				mstate = MODE_ACTION;
-				continue;
-			}
-			break;
-
-		case MODE_ACTION_APPLY:
-			switch (op) {
-			case MODE_EQUALS:
-				expr->file_mode &= ~who;
-				expr->dir_mode &= ~who;
-				// Fallthrough
-			case MODE_PLUS:
-				expr->file_mode |= file_change;
-				expr->dir_mode |= dir_change;
-				break;
-			case MODE_MINUS:
-				expr->file_mode &= ~file_change;
-				expr->dir_mode &= ~dir_change;
-				break;
-			}
-			// Fallthrough
-
-		case MODE_ACTION:
-			if (who == 0) {
-				who = 0777;
-			}
-
-			switch (*i) {
-			case '+':
-				op = MODE_PLUS;
-				mstate = MODE_OP;
-				break;
-			case '-':
-				op = MODE_MINUS;
-				mstate = MODE_OP;
-				break;
-			case '=':
-				op = MODE_EQUALS;
-				mstate = MODE_OP;
-				break;
-
-			case ',':
-				if (mstate == MODE_ACTION_APPLY) {
-					mstate = MODE_CLAUSE;
-				} else {
-					goto fail;
-				}
-				break;
-
-			case '\0':
-				if (mstate == MODE_ACTION_APPLY) {
-					goto done;
-				} else {
-					goto fail;
-				}
-
-			default:
-				goto fail;
-			}
-			break;
-
-		case MODE_OP:
-			switch (*i) {
-			case 'u':
-				file_change = (expr->file_mode >> 6) & 07;
-				dir_change = (expr->dir_mode >> 6) & 07;
-				break;
-			case 'g':
-				file_change = (expr->file_mode >> 3) & 07;
-				dir_change = (expr->dir_mode >> 3) & 07;
-				break;
-			case 'o':
-				file_change = expr->file_mode & 07;
-				dir_change = expr->dir_mode & 07;
-				break;
-
-			default:
-				file_change = 0;
-				dir_change = 0;
-				mstate = MODE_PERM;
-				continue;
-			}
-
-			file_change |= (file_change << 6) | (file_change << 3);
-			file_change &= who;
-			dir_change |= (dir_change << 6) | (dir_change << 3);
-			dir_change &= who;
-			mstate = MODE_ACTION_APPLY;
-			break;
-
-		case MODE_PERM:
-			switch (*i) {
-			case 'r':
-				file_change |= who & 0444;
-				dir_change |= who & 0444;
-				break;
-			case 'w':
-				file_change |= who & 0222;
-				dir_change |= who & 0222;
-				break;
-			case 'x':
-				file_change |= who & 0111;
-				// Fallthrough
-			case 'X':
-				dir_change |= who & 0111;
-				break;
-			case 's':
-				if (who & 0700) {
-					file_change |= S_ISUID;
-					dir_change |= S_ISUID;
-				}
-				if (who & 0070) {
-					file_change |= S_ISGID;
-					dir_change |= S_ISGID;
-				}
-				break;
-			case 't':
-				file_change |= S_ISVTX;
-				dir_change |= S_ISVTX;
-				break;
-			default:
-				mstate = MODE_ACTION_APPLY;
-				continue;
-			}
-			break;
-		}
-
-		++i;
-	}
-
-done:
-	return 0;
-
-fail:
-	parse_error(state, "'%s' is an invalid mode.\n", mode);
-	return -1;
-}
-
-/**
- * Parse -perm MODE.
- */
-static struct expr *parse_perm(struct parser_state *state, int field, int arg2) {
-	struct expr *expr = parse_unary_test(state, eval_perm);
-	if (!expr) {
-		return NULL;
-	}
-
-	const char *mode = expr->sdata;
-	switch (mode[0]) {
-	case '-':
-		expr->mode_cmp = MODE_ALL;
-		++mode;
-		break;
-	case '/':
-		expr->mode_cmp = MODE_ANY;
-		++mode;
-		break;
-	case '+':
-		if (mode[1] >= '0' && mode[1] <= '9') {
-			expr->mode_cmp = MODE_ANY;
-			++mode;
-			break;
-		}
-		// Fallthrough
-	default:
-		expr->mode_cmp = MODE_EXACT;
-		break;
-	}
-
-	if (parse_mode(state, mode, expr) != 0) {
-		goto fail;
-	}
-
-	expr->cost = STAT_COST;
-
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -print.
- */
-static struct expr *parse_print(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_nullary_action(state, eval_fprint);
-	if (expr) {
-		init_print_expr(state, expr);
-	}
-	return expr;
-}
-
-/**
- * Parse -print0.
- */
-static struct expr *parse_print0(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_nullary_action(state, eval_fprint0);
-	if (expr) {
-		init_print_expr(state, expr);
-	}
-	return expr;
-}
-
-/**
- * Parse -printf FORMAT.
- */
-static struct expr *parse_printf(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_unary_action(state, eval_fprintf);
-	if (!expr) {
-		return NULL;
-	}
-
-	init_print_expr(state, expr);
-
-	expr->printf = parse_bfs_printf(expr->sdata, state->cmdline);
-	if (!expr->printf) {
-		free_expr(expr);
-		return NULL;
-	}
-
-	return expr;
-}
-
-/**
- * Parse -printx.
- */
-static struct expr *parse_printx(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_nullary_action(state, eval_fprintx);
-	if (expr) {
-		init_print_expr(state, expr);
-	}
-	return expr;
-}
-
-/**
- * Parse -prune.
- */
-static struct expr *parse_prune(struct parser_state *state, int arg1, int arg2) {
-	state->prune_arg = state->argv[0];
-
-	struct expr *expr = parse_nullary_action(state, eval_prune);
-	if (expr) {
-		expr_set_always_true(expr);
-	}
-	return expr;
-}
-
-/**
- * Parse -quit.
- */
-static struct expr *parse_quit(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_nullary_action(state, eval_quit);
-	if (expr) {
-		expr_set_never_returns(expr);
-	}
-	return expr;
-}
-
-/**
- * Parse -i?regex.
- */
-static struct expr *parse_regex(struct parser_state *state, int flags, int arg2) {
-	struct expr *expr = parse_unary_test(state, eval_regex);
-	if (!expr) {
-		goto fail;
-	}
-
-	expr->regex = malloc(sizeof(regex_t));
-	if (!expr->regex) {
-		perror("malloc()");
-		goto fail;
-	}
-
-	int err = regcomp(expr->regex, expr->sdata, state->regex_flags | flags);
-	if (err != 0) {
-		char *str = xregerror(err, expr->regex);
-		if (str) {
-			parse_error(state, "%s %s: %s.\n", expr->argv[0], expr->argv[1], str);
-			free(str);
-		} else {
-			perror("xregerror()");
-		}
-		goto fail_regex;
-	}
-
-	return expr;
-
-fail_regex:
-	free(expr->regex);
-	expr->regex = NULL;
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -E.
- */
-static struct expr *parse_regex_extended(struct parser_state *state, int arg1, int arg2) {
-	state->regex_flags = REG_EXTENDED;
-	return parse_nullary_flag(state);
-}
-
-/**
- * Parse -regextype TYPE.
- */
-static struct expr *parse_regextype(struct parser_state *state, int arg1, int arg2) {
-	const char *type;
-	struct expr *expr = parse_unary_positional_option(state, &type);
-	if (!expr) {
-		goto fail;
-	}
-
-	FILE *file = stderr;
-
-	if (strcmp(type, "posix-basic") == 0) {
-		state->regex_flags = 0;
-	} else if (strcmp(type, "posix-extended") == 0) {
-		state->regex_flags = REG_EXTENDED;
-	} else if (strcmp(type, "help") == 0) {
-		state->just_info = true;
-		file = stdout;
-		goto fail_list_types;
-	} else {
-		goto fail_bad_type;
-	}
-
-	return expr;
-
-fail_bad_type:
-	parse_error(state, "Unsupported -regextype '%s'.\n\n", type);
-fail_list_types:
-	fputs("Supported types are:\n\n", file);
-	fputs("  posix-basic:    POSIX basic regular expressions (BRE)\n", file);
-	fputs("  posix-extended: POSIX extended regular expressions (ERE)\n", file);
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -samefile FILE.
- */
-static struct expr *parse_samefile(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_unary_test(state, eval_samefile);
-	if (!expr) {
-		return NULL;
-	}
-
-	struct bfs_stat sb;
-	if (stat_arg(state, expr, &sb) != 0) {
-		free_expr(expr);
-		return NULL;
-	}
-
-	expr->dev = sb.dev;
-	expr->ino = sb.ino;
-
-	expr->cost = STAT_COST;
-	expr->probability = 0.01;
-
-	return expr;
-}
-
-/**
- * Parse -S STRATEGY.
- */
-static struct expr *parse_search_strategy(struct parser_state *state, int arg1, int arg2) {
-	const char *flag = state->argv[0];
-	const char *arg = state->argv[1];
-	if (!arg) {
-		parse_error(state, "%s needs an argument.\n", flag);
-		return NULL;
-	}
-
-	struct cmdline *cmdline = state->cmdline;
-	FILE *file = stderr;
-
-	if (strcmp(arg, "bfs") == 0) {
-		cmdline->strategy = BFTW_BFS;
-	} else if (strcmp(arg, "dfs") == 0) {
-		cmdline->strategy = BFTW_DFS;
-	} else if (strcmp(arg, "ids") == 0) {
-		cmdline->strategy = BFTW_IDS;
-	} else if (strcmp(arg, "help") == 0) {
-		state->just_info = true;
-		file = stdout;
-		goto fail_list_strategies;
-	} else {
-		goto fail_bad_strategy;
-	}
-
-	return parse_unary_flag(state);
-
-fail_bad_strategy:
-	parse_error(state, "Unrecognized search strategy '%s'.\n\n", arg);
-fail_list_strategies:
-	fputs("Supported search strategies:\n\n", file);
-	fputs("  bfs: breadth-first search\n", file);
-	fputs("  dfs: depth-first search\n", file);
-	fputs("  ids: iterative deepening search\n", file);
-	return NULL;
-}
-
-/**
- * Parse -size N[cwbkMGTP]?.
- */
-static struct expr *parse_size(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_unary_test(state, eval_size);
-	if (!expr) {
-		return NULL;
-	}
-
-	const char *unit = parse_icmp(state, expr->sdata, expr, IF_PARTIAL_OK);
-	if (!unit) {
-		goto fail;
-	}
-
-	if (strlen(unit) > 1) {
-		goto bad_unit;
-	}
-
-	switch (*unit) {
-	case '\0':
-	case 'b':
-		expr->size_unit = SIZE_BLOCKS;
-		break;
-	case 'c':
-		expr->size_unit = SIZE_BYTES;
-		break;
-	case 'w':
-		expr->size_unit = SIZE_WORDS;
-		break;
-	case 'k':
-		expr->size_unit = SIZE_KB;
-		break;
-	case 'M':
-		expr->size_unit = SIZE_MB;
-		break;
-	case 'G':
-		expr->size_unit = SIZE_GB;
-		break;
-	case 'T':
-		expr->size_unit = SIZE_TB;
-		break;
-	case 'P':
-		expr->size_unit = SIZE_PB;
-		break;
-
-	default:
-		goto bad_unit;
-	}
-
-	expr->cost = STAT_COST;
-	expr->probability = expr->cmp_flag == CMP_EXACT ? 0.01 : 0.50;
-
-	return expr;
-
-bad_unit:
-	parse_error(state, "%s %s: Expected a size unit (one of cwbkMGTP); found '%s'.\n",
-	            expr->argv[0], expr->argv[1], unit);
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -sparse.
- */
-static struct expr *parse_sparse(struct parser_state *state, int arg1, int arg2) {
-	struct expr *expr = parse_nullary_test(state, eval_sparse);
-	if (expr) {
-		expr->cost = STAT_COST;
-	}
-	return expr;
-}
-
-/**
- * Parse -x?type [bcdpflsD].
- */
-static struct expr *parse_type(struct parser_state *state, int x, int arg2) {
-	eval_fn *eval = x ? eval_xtype : eval_type;
-	struct expr *expr = parse_unary_test(state, eval);
-	if (!expr) {
-		return NULL;
-	}
-
-	enum bftw_typeflag types = 0;
-	double probability = 0.0;
-
-	const char *c = expr->sdata;
-	while (true) {
-		enum bftw_typeflag type;
-		double type_prob;
-
-		switch (*c) {
-		case 'b':
-			type = BFTW_BLK;
-			type_prob = 0.00000721183;
-			break;
-		case 'c':
-			type = BFTW_CHR;
-			type_prob = 0.0000499855;
-			break;
-		case 'd':
-			type = BFTW_DIR;
-			type_prob = 0.114475;
-			break;
-		case 'D':
-			type = BFTW_DOOR;
-			type_prob = 0.000001;
-			break;
-		case 'p':
-			type = BFTW_FIFO;
-			type_prob = 0.00000248684;
-			break;
-		case 'f':
-			type = BFTW_REG;
-			type_prob = 0.859772;
-			break;
-		case 'l':
-			type = BFTW_LNK;
-			type_prob = 0.0256816;
-			break;
-		case 's':
-			type = BFTW_SOCK;
-			type_prob = 0.0000116881;
-			break;
-		case 'w':
-			type = BFTW_WHT;
-			type_prob = 0.000001;
-			break;
-
-		case '\0':
-			parse_error(state, "%s %s: Expected a type flag.\n", expr->argv[0], expr->argv[1]);
-			goto fail;
-
-		default:
-			parse_error(state, "%s %s: Unknown type flag '%c' (expected one of [bcdpflsD]).\n",
-			            expr->argv[0], expr->argv[1], *c);
-			goto fail;
-		}
-
-		if (!(types & type)) {
-			types |= type;
-			probability += type_prob;
-		}
-
-		++c;
-		if (*c == '\0') {
-			break;
-		} else if (*c == ',') {
-			++c;
-			continue;
-		} else {
-			parse_error(state, "%s %s: Types must be comma-separated.\n", expr->argv[0], expr->argv[1]);
-			goto fail;
-		}
-	}
-
-	expr->idata = types;
-	expr->probability = probability;
-
-	if (x && state->cmdline->optlevel < 4) {
-		// Since -xtype dereferences symbolic links, it may have side
-		// effects such as reporting permission errors, and thus
-		// shouldn't be re-ordered without aggressive optimizations
-		expr->pure = false;
-	}
-
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Parse -(no)?warn.
- */
-static struct expr *parse_warn(struct parser_state *state, int warn, int arg2) {
-	state->warn = warn;
-	return parse_nullary_positional_option(state);
-}
-
-/**
- * Parse -xattr.
- */
-static struct expr *parse_xattr(struct parser_state *state, int arg1, int arg2) {
-#if BFS_CAN_CHECK_XATTRS
-	struct expr *expr = parse_nullary_test(state, eval_xattr);
-	if (expr) {
-		expr->cost = STAT_COST;
-		expr->probability = 0.01;
-	}
-	return expr;
-#else
-	parse_error(state, "%s is missing platform support.\n", state->argv[0]);
-	return NULL;
-#endif
-}
-
-/**
- * Launch a pager for the help output.
- */
-static CFILE *launch_pager(pid_t *pid, CFILE *cout) {
-	char *pager = getenv("PAGER");
-	if (!pager) {
-		pager = "more";
-	}
-
-	int pipefd[2];
-	if (pipe(pipefd) != 0) {
-		goto fail;
-	}
-
-	FILE *file = fdopen(pipefd[1], "w");
-	if (!file) {
-		goto fail_pipe;
-	}
-	pipefd[1] = -1;
-
-	CFILE *ret = cfdup(file, NULL);
-	if (!ret) {
-		goto fail_file;
-	}
-	file = NULL;
-	ret->close = true;
-	ret->colors = cout->colors;
-
-	struct bfs_spawn ctx;
-	if (bfs_spawn_init(&ctx) != 0) {
-		goto fail_ret;
-	}
-
-	if (bfs_spawn_setflags(&ctx, BFS_SPAWN_USEPATH) != 0) {
-		goto fail_ctx;
-	}
-
-	if (bfs_spawn_addclose(&ctx, fileno(ret->file)) != 0) {
-		goto fail_ctx;
-	}
-	if (bfs_spawn_adddup2(&ctx, pipefd[0], STDIN_FILENO) != 0) {
-		goto fail_ctx;
-	}
-	if (bfs_spawn_addclose(&ctx, pipefd[0]) != 0) {
-		goto fail_ctx;
-	}
-
-	char *argv[] = {
-		pager,
-		NULL,
-	};
-
-	extern char **environ;
-	char **envp = environ;
-
-	if (!getenv("LESS")) {
-		size_t envc;
-		for (envc = 0; environ[envc]; ++envc);
-		++envc;
-
-		envp = malloc((envc + 1)*sizeof(*envp));
-		if (!envp) {
-			goto fail_ctx;
-		}
-
-		memcpy(envp, environ, (envc - 1)*sizeof(*envp));
-		envp[envc - 1] = "LESS=FKRX";
-		envp[envc] = NULL;
-	}
-
-	*pid = bfs_spawn(pager, &ctx, argv, envp);
-	if (*pid < 0) {
-		goto fail_envp;
-	}
-
-	close(pipefd[0]);
-	if (envp != environ) {
-		free(envp);
-	}
-	bfs_spawn_destroy(&ctx);
-	return ret;
-
-fail_envp:
-	if (envp != environ) {
-		free(envp);
-	}
-fail_ctx:
-	bfs_spawn_destroy(&ctx);
-fail_ret:
-	cfclose(ret);
-fail_file:
-	if (file) {
-		fclose(file);
-	}
-fail_pipe:
-	if (pipefd[1] >= 0) {
-		close(pipefd[1]);
-	}
-	if (pipefd[0] >= 0) {
-		close(pipefd[0]);
-	}
-fail:
-	return cout;
-}
-
-/**
- * "Parse" -help.
- */
-static struct expr *parse_help(struct parser_state *state, int arg1, int arg2) {
-	CFILE *cout = state->cmdline->cout;
-
-	pid_t pager = -1;
-	if (state->stdout_tty) {
-		cout = launch_pager(&pager, cout);
-	}
-
-	cfprintf(cout, "Usage: ${ex}%s${rs} [${cyn}flags${rs}...] [${mag}paths${rs}...] [${blu}expression${rs}...]\n\n",
-		 state->command);
-
-	cfprintf(cout, "${ex}bfs${rs} is compatible with ${ex}find${rs}, with some extensions. "
-		       "${cyn}Flags${rs} (${cyn}-H${rs}/${cyn}-L${rs}/${cyn}-P${rs} etc.), ${mag}paths${rs},\n"
-		       "and ${blu}expressions${rs} may be freely mixed in any order.\n\n");
-
-	cfprintf(cout, "${bld}Flags:${rs}\n\n");
-
-	cfprintf(cout, "  ${cyn}-H${rs}\n");
-	cfprintf(cout, "      Follow symbolic links on the command line, but not while searching\n");
-	cfprintf(cout, "  ${cyn}-L${rs}\n");
-	cfprintf(cout, "      Follow all symbolic links\n");
-	cfprintf(cout, "  ${cyn}-P${rs}\n");
-	cfprintf(cout, "      Never follow symbolic links (the default)\n");
-
-	cfprintf(cout, "  ${cyn}-E${rs}\n");
-	cfprintf(cout, "      Use extended regular expressions (same as ${blu}-regextype${rs} ${bld}posix-extended${rs})\n");
-	cfprintf(cout, "  ${cyn}-X${rs}\n");
-	cfprintf(cout, "      Filter out files with non-${ex}xargs${rs}-safe names\n");
-	cfprintf(cout, "  ${cyn}-d${rs}\n");
-	cfprintf(cout, "      Search in post-order (same as ${blu}-depth${rs})\n");
-	cfprintf(cout, "  ${cyn}-x${rs}\n");
-	cfprintf(cout, "      Don't descend into other mount points (same as ${blu}-xdev${rs})\n");
-
-	cfprintf(cout, "  ${cyn}-f${rs} ${mag}PATH${rs}\n");
-	cfprintf(cout, "      Treat ${mag}PATH${rs} as a path to search (useful if begins with a dash)\n");
-	cfprintf(cout, "  ${cyn}-D${rs} ${bld}FLAG${rs}\n");
-	cfprintf(cout, "      Turn on a debugging flag (see ${cyn}-D${rs} ${bld}help${rs})\n");
-	cfprintf(cout, "  ${cyn}-O${rs}${bld}N${rs}\n");
-	cfprintf(cout, "      Enable optimization level ${bld}N${rs} (default: 3)\n");
-	cfprintf(cout, "  ${cyn}-S${rs} ${bld}bfs${rs}|${bld}dfs${rs}|${bld}ids${rs}\n");
-	cfprintf(cout, "      Use ${bld}b${rs}readth-${bld}f${rs}irst/${bld}d${rs}epth-${bld}f${rs}irst/${bld}i${rs}terative ${bld}d${rs}eepening ${bld}s${rs}earch (default: ${cyn}-S${rs} ${bld}bfs${rs})\n\n");
-
-	cfprintf(cout, "${bld}Operators:${rs}\n\n");
-
-	cfprintf(cout, "  ${red}(${rs} ${blu}expression${rs} ${red})${rs}\n\n");
-
-	cfprintf(cout, "  ${red}!${rs} ${blu}expression${rs}\n");
-	cfprintf(cout, "  ${red}-not${rs} ${blu}expression${rs}\n\n");
-
-	cfprintf(cout, "  ${blu}expression${rs} ${blu}expression${rs}\n");
-	cfprintf(cout, "  ${blu}expression${rs} ${red}-a${rs} ${blu}expression${rs}\n");
-	cfprintf(cout, "  ${blu}expression${rs} ${red}-and${rs} ${blu}expression${rs}\n\n");
-
-	cfprintf(cout, "  ${blu}expression${rs} ${red}-o${rs} ${blu}expression${rs}\n");
-	cfprintf(cout, "  ${blu}expression${rs} ${red}-or${rs} ${blu}expression${rs}\n\n");
-
-	cfprintf(cout, "  ${blu}expression${rs} ${red},${rs} ${blu}expression${rs}\n\n");
-
-	cfprintf(cout, "${bld}Options:${rs}\n\n");
-
-	cfprintf(cout, "  ${blu}-color${rs}\n");
-	cfprintf(cout, "  ${blu}-nocolor${rs}\n");
-	cfprintf(cout, "      Turn colors on or off (default: ${blu}-color${rs} if outputting to a terminal,\n");
-	cfprintf(cout, "      ${blu}-nocolor${rs} otherwise)\n");
-	cfprintf(cout, "  ${blu}-daystart${rs}\n");
-	cfprintf(cout, "      Measure times relative to the start of today\n");
-	cfprintf(cout, "  ${blu}-depth${rs}\n");
-	cfprintf(cout, "      Search in post-order (descendents first)\n");
-	cfprintf(cout, "  ${blu}-follow${rs}\n");
-	cfprintf(cout, "      Follow all symbolic links (same as ${cyn}-L${rs})\n");
-	cfprintf(cout, "  ${blu}-ignore_readdir_race${rs}\n");
-	cfprintf(cout, "  ${blu}-noignore_readdir_race${rs}\n");
-	cfprintf(cout, "      Whether to report an error if ${ex}bfs${rs} detects that the file tree is modified\n");
-	cfprintf(cout, "      during the search (default: ${blu}-noignore_readdir_race${rs})\n");
-	cfprintf(cout, "  ${blu}-maxdepth${rs} ${bld}N${rs}\n");
-	cfprintf(cout, "  ${blu}-mindepth${rs} ${bld}N${rs}\n");
-	cfprintf(cout, "      Ignore files deeper/shallower than ${bld}N${rs}\n");
-	cfprintf(cout, "  ${blu}-mount${rs}\n");
-	cfprintf(cout, "  ${blu}-xdev${rs}\n");
-	cfprintf(cout, "      Don't descend into other mount points\n");
-	cfprintf(cout, "  ${blu}-noleaf${rs}\n");
-	cfprintf(cout, "      Ignored; for compatibility with GNU find\n");
-	cfprintf(cout, "  ${blu}-regextype${rs} ${bld}TYPE${rs}\n");
-	cfprintf(cout, "      Use ${bld}TYPE${rs}-flavored regexes (default: ${bld}posix-basic${rs}; see ${blu}-regextype${rs}"
-	                " ${bld}help${rs})\n");
-	cfprintf(cout, "  ${blu}-unique${rs}\n");
-	cfprintf(cout, "      Skip any files that have already been seen\n");
-	cfprintf(cout, "  ${blu}-warn${rs}\n");
-	cfprintf(cout, "  ${blu}-nowarn${rs}\n");
-	cfprintf(cout, "      Turn on or off warnings about the command line\n\n");
-
-	cfprintf(cout, "${bld}Tests:${rs}\n\n");
-
-#if BFS_CAN_CHECK_ACL
-	cfprintf(cout, "  ${blu}-acl${rs}\n");
-	cfprintf(cout, "      Find files with a non-trivial Access Control List\n");
-#endif
-	cfprintf(cout, "  ${blu}-${rs}[${blu}aBcm${rs}]${blu}min${rs} ${bld}[-+]N${rs}\n");
-	cfprintf(cout, "      Find files ${blu}a${rs}ccessed/${blu}B${rs}irthed/${blu}c${rs}hanged/${blu}m${rs}odified ${bld}N${rs} minutes ago\n");
-	cfprintf(cout, "  ${blu}-${rs}[${blu}aBcm${rs}]${blu}newer${rs} ${bld}FILE${rs}\n");
-	cfprintf(cout, "      Find files ${blu}a${rs}ccessed/${blu}B${rs}irthed/${blu}c${rs}hanged/${blu}m${rs}odified more recently than ${bld}FILE${rs} was\n"
-	               "      modified\n");
-	cfprintf(cout, "  ${blu}-${rs}[${blu}aBcm${rs}]${blu}time${rs} ${bld}[-+]N${rs}\n");
-	cfprintf(cout, "      Find files ${blu}a${rs}ccessed/${blu}B${rs}irthed/${blu}c${rs}hanged/${blu}m${rs}odified ${bld}N${rs} days ago\n");
-#if BFS_CAN_CHECK_CAPABILITIES
-	cfprintf(cout, "  ${blu}-capable${rs}\n");
-	cfprintf(cout, "      Find files with POSIX.1e capabilities set\n");
-#endif
-	cfprintf(cout, "  ${blu}-depth${rs} ${bld}[-+]N${rs}\n");
-	cfprintf(cout, "      Find files with depth ${bld}N${rs}\n");
-	cfprintf(cout, "  ${blu}-empty${rs}\n");
-	cfprintf(cout, "      Find empty files/directories\n");
-	cfprintf(cout, "  ${blu}-executable${rs}\n");
-	cfprintf(cout, "  ${blu}-readable${rs}\n");
-	cfprintf(cout, "  ${blu}-writable${rs}\n");
-	cfprintf(cout, "      Find files the current user can execute/read/write\n");
-	cfprintf(cout, "  ${blu}-false${rs}\n");
-	cfprintf(cout, "  ${blu}-true${rs}\n");
-	cfprintf(cout, "      Always false/true\n");
-	cfprintf(cout, "  ${blu}-fstype${rs} ${bld}TYPE${rs}\n");
-	cfprintf(cout, "      Find files on file systems with the given ${bld}TYPE${rs}\n");
-	cfprintf(cout, "  ${blu}-gid${rs} ${bld}[-+]N${rs}\n");
-	cfprintf(cout, "  ${blu}-uid${rs} ${bld}[-+]N${rs}\n");
-	cfprintf(cout, "      Find files owned by group/user ID ${bld}N${rs}\n");
-	cfprintf(cout, "  ${blu}-group${rs} ${bld}NAME${rs}\n");
-	cfprintf(cout, "  ${blu}-user${rs}  ${bld}NAME${rs}\n");
-	cfprintf(cout, "      Find files owned by the group/user ${bld}NAME${rs}\n");
-	cfprintf(cout, "  ${blu}-hidden${rs}\n");
-	cfprintf(cout, "  ${blu}-nohidden${rs}\n");
-	cfprintf(cout, "      Find hidden files, or filter them out\n");
-#ifdef FNM_CASEFOLD
-	cfprintf(cout, "  ${blu}-ilname${rs} ${bld}GLOB${rs}\n");
-	cfprintf(cout, "  ${blu}-iname${rs}  ${bld}GLOB${rs}\n");
-	cfprintf(cout, "  ${blu}-ipath${rs}  ${bld}GLOB${rs}\n");
-	cfprintf(cout, "  ${blu}-iregex${rs} ${bld}REGEX${rs}\n");
-	cfprintf(cout, "  ${blu}-iwholename${rs} ${bld}GLOB${rs}\n");
-	cfprintf(cout, "      Case-insensitive versions of ${blu}-lname${rs}/${blu}-name${rs}/${blu}-path${rs}"
-	               "/${blu}-regex${rs}/${blu}-wholename${rs}\n");
-#endif
-	cfprintf(cout, "  ${blu}-inum${rs} ${bld}[-+]N${rs}\n");
-	cfprintf(cout, "      Find files with inode number ${bld}N${rs}\n");
-	cfprintf(cout, "  ${blu}-links${rs} ${bld}[-+]N${rs}\n");
-	cfprintf(cout, "      Find files with ${bld}N${rs} hard links\n");
-	cfprintf(cout, "  ${blu}-lname${rs} ${bld}GLOB${rs}\n");
-	cfprintf(cout, "      Find symbolic links whose target matches the ${bld}GLOB${rs}\n");
-	cfprintf(cout, "  ${blu}-name${rs} ${bld}GLOB${rs}\n");
-	cfprintf(cout, "      Find files whose name matches the ${bld}GLOB${rs}\n");
-	cfprintf(cout, "  ${blu}-newer${rs} ${bld}FILE${rs}\n");
-	cfprintf(cout, "      Find files newer than ${bld}FILE${rs}\n");
-	cfprintf(cout, "  ${blu}-newer${rs}${bld}XY${rs} ${bld}REFERENCE${rs}\n");
-	cfprintf(cout, "      Find files whose ${bld}X${rs} time is newer than the ${bld}Y${rs} time of"
-	               " ${bld}REFERENCE${rs}.  ${bld}X${rs} and ${bld}Y${rs}\n");
-	cfprintf(cout, "      can be any of [${bld}aBcm${rs}].\n");
-	cfprintf(cout, "  ${blu}-nogroup${rs}\n");
-	cfprintf(cout, "  ${blu}-nouser${rs}\n");
-	cfprintf(cout, "      Find files owned by nonexistent groups/users\n");
-	cfprintf(cout, "  ${blu}-path${rs} ${bld}GLOB${rs}\n");
-	cfprintf(cout, "  ${blu}-wholename${rs} ${bld}GLOB${rs}\n");
-	cfprintf(cout, "      Find files whose entire path matches the ${bld}GLOB${rs}\n");
-	cfprintf(cout, "  ${blu}-perm${rs} ${bld}[-]MODE${rs}\n");
-	cfprintf(cout, "      Find files with a matching mode\n");
-	cfprintf(cout, "  ${blu}-regex${rs} ${bld}REGEX${rs}\n");
-	cfprintf(cout, "      Find files whose entire path matches the regular expression ${bld}REGEX${rs}\n");
-	cfprintf(cout, "  ${blu}-samefile${rs} ${bld}FILE${rs}\n");
-	cfprintf(cout, "      Find hard links to ${bld}FILE${rs}\n");
-	cfprintf(cout, "  ${blu}-size${rs} ${bld}[-+]N[cwbkMGTP]${rs}\n");
-	cfprintf(cout, "      Find files with the given size, in 1-byte ${bld}c${rs}haracters, 2-byte ${bld}w${rs}ords,\n");
-	cfprintf(cout, "      512-byte ${bld}b${rs}locks (default), or ${bld}k${rs}iB/${bld}M${rs}iB/${bld}G${rs}iB/${bld}T${rs}iB/${bld}P${rs}iB\n");
-	cfprintf(cout, "  ${blu}-sparse${rs}\n");
-	cfprintf(cout, "      Find files that occupy fewer disk blocks than expected\n");
-	cfprintf(cout, "  ${blu}-type${rs} ${bld}[bcdlpfswD]${rs}\n");
-	cfprintf(cout, "      Find files of the given type\n");
-	cfprintf(cout, "  ${blu}-used${rs} ${bld}[-+]N${rs}\n");
-	cfprintf(cout, "      Find files last accessed ${bld}N${rs} days after they were changed\n");
-#if BFS_CAN_CHECK_XATTRS
-	cfprintf(cout, "  ${blu}-xattr${rs}\n");
-	cfprintf(cout, "      Find files with extended attributes\n");
-#endif
-	cfprintf(cout, "  ${blu}-xtype${rs} ${bld}[bcdlpfswD]${rs}\n");
-	cfprintf(cout, "      Find files of the given type, following links when ${blu}-type${rs} would not, and\n");
-	cfprintf(cout, "      vice versa\n\n");
-
-	cfprintf(cout, "${bld}Actions:${rs}\n\n");
-
-	cfprintf(cout, "  ${blu}-delete${rs}\n");
-	cfprintf(cout, "  ${blu}-rm${rs}\n");
-	cfprintf(cout, "      Delete any found files (implies ${blu}-depth${rs})\n");
-	cfprintf(cout, "  ${blu}-exec${rs} ${bld}command ... {} ;${rs}\n");
-	cfprintf(cout, "      Execute a command\n");
-	cfprintf(cout, "  ${blu}-exec${rs} ${bld}command ... {} +${rs}\n");
-	cfprintf(cout, "      Execute a command with multiple files at once\n");
-	cfprintf(cout, "  ${blu}-ok${rs} ${bld}command ... {} ;${rs}\n");
-	cfprintf(cout, "      Prompt the user whether to execute a command\n");
-	cfprintf(cout, "  ${blu}-execdir${rs} ${bld}command ... {} ;${rs}\n");
-	cfprintf(cout, "  ${blu}-execdir${rs} ${bld}command ... {} +${rs}\n");
-	cfprintf(cout, "  ${blu}-okdir${rs} ${bld}command ... {} ;${rs}\n");
-	cfprintf(cout, "      Like ${blu}-exec${rs}/${blu}-ok${rs}, but run the command in the same directory as the found\n");
-	cfprintf(cout, "      file(s)\n");
-	cfprintf(cout, "  ${blu}-exit${rs} [${bld}STATUS${rs}]\n");
-	cfprintf(cout, "      Exit immediately with the given status (%d if unspecified)\n", EXIT_SUCCESS);
-	cfprintf(cout, "  ${blu}-fls${rs} ${bld}FILE${rs}\n");
-	cfprintf(cout, "  ${blu}-fprint${rs} ${bld}FILE${rs}\n");
-	cfprintf(cout, "  ${blu}-fprint0${rs} ${bld}FILE${rs}\n");
-	cfprintf(cout, "  ${blu}-fprintf${rs} ${bld}FORMAT${rs} ${bld}FILE${rs}\n");
-	cfprintf(cout, "      Like ${blu}-ls${rs}/${blu}-print${rs}/${blu}-print0${rs}/${blu}-printf${rs}, but write to ${bld}FILE${rs} instead of standard\n"
-	               "      output\n");
-	cfprintf(cout, "  ${blu}-ls${rs}\n");
-	cfprintf(cout, "      List files like ${ex}ls${rs} ${bld}-dils${rs}\n");
-	cfprintf(cout, "  ${blu}-nohidden${rs}\n");
-	cfprintf(cout, "      Filter out hidden files and directories\n");
-	cfprintf(cout, "  ${blu}-print${rs}\n");
-	cfprintf(cout, "      Print the path to the found file\n");
-	cfprintf(cout, "  ${blu}-print0${rs}\n");
-	cfprintf(cout, "      Like ${blu}-print${rs}, but use the null character ('\\0') as a separator rather than\n");
-	cfprintf(cout, "      newlines\n");
-	cfprintf(cout, "  ${blu}-printf${rs} ${bld}FORMAT${rs}\n");
-	cfprintf(cout, "      Print according to a format string (see ${ex}man${rs} ${bld}find${rs}).  The additional format\n");
-	cfprintf(cout, "      directives %%w and %%W${bld}k${rs} for printing file birth times are supported.\n");
-	cfprintf(cout, "  ${blu}-printx${rs}\n");
-	cfprintf(cout, "      Like ${blu}-print${rs}, but escape whitespace and quotation characters, to make the\n");
-	cfprintf(cout, "      output safe for ${ex}xargs${rs}.  Consider using ${blu}-print0${rs} and ${ex}xargs${rs} ${bld}-0${rs} instead.\n");
-	cfprintf(cout, "  ${blu}-prune${rs}\n");
-	cfprintf(cout, "      Don't descend into this directory\n");
-	cfprintf(cout, "  ${blu}-quit${rs}\n");
-	cfprintf(cout, "      Quit immediately\n");
-	cfprintf(cout, "  ${blu}-version${rs}\n");
-	cfprintf(cout, "      Print version information\n");
-	cfprintf(cout, "  ${blu}-help${rs}\n");
-	cfprintf(cout, "      Print this help message\n\n");
-
-	cfprintf(cout, "%s\n", BFS_HOMEPAGE);
-
-	if (pager > 0) {
-		cfclose(cout);
-		waitpid(pager, NULL, 0);
-	}
-
-	state->just_info = true;
-	return NULL;
-}
-
-/**
- * "Parse" -version.
- */
-static struct expr *parse_version(struct parser_state *state, int arg1, int arg2) {
-	cfprintf(state->cmdline->cout, "${ex}bfs${rs} ${bld}%s${rs}\n\n", BFS_VERSION);
-
-	printf("%s\n", BFS_HOMEPAGE);
-
-	state->just_info = true;
-	return NULL;
-}
-
-typedef struct expr *parse_fn(struct parser_state *state, int arg1, int arg2);
-
-/**
- * An entry in the parse table for literals.
- */
-struct table_entry {
-	char *arg;
-	parse_fn *parse;
-	int arg1;
-	int arg2;
-	bool prefix;
-};
-
-/**
- * The parse table for literals.
- */
-static const struct table_entry parse_table[] = {
-	{"--"},
-	{"--help", parse_help},
-	{"--version", parse_version},
-	{"-Bmin", parse_time, BFS_STAT_BTIME, MINUTES},
-	{"-Bnewer", parse_newer, BFS_STAT_BTIME},
-	{"-Btime", parse_time, BFS_STAT_BTIME, DAYS},
-	{"-D", parse_debug},
-	{"-E", parse_regex_extended},
-	{"-H", parse_follow, BFTW_COMFOLLOW, false},
-	{"-L", parse_follow, BFTW_LOGICAL, false},
-	{"-O", parse_optlevel, 0, 0, true},
-	{"-P", parse_follow, 0, false},
-	{"-S", parse_search_strategy},
-	{"-X", parse_xargs_safe},
-	{"-a"},
-	{"-acl", parse_acl},
-	{"-amin", parse_time, BFS_STAT_ATIME, MINUTES},
-	{"-and"},
-	{"-anewer", parse_newer, BFS_STAT_ATIME},
-	{"-atime", parse_time, BFS_STAT_ATIME, DAYS},
-	{"-capable", parse_capable},
-	{"-cmin", parse_time, BFS_STAT_CTIME, MINUTES},
-	{"-cnewer", parse_newer, BFS_STAT_CTIME},
-	{"-color", parse_color, true},
-	{"-ctime", parse_time, BFS_STAT_CTIME, DAYS},
-	{"-d", parse_depth},
-	{"-daystart", parse_daystart},
-	{"-delete", parse_delete},
-	{"-depth", parse_depth_n},
-	{"-empty", parse_empty},
-	{"-exec", parse_exec, 0},
-	{"-execdir", parse_exec, BFS_EXEC_CHDIR},
-	{"-executable", parse_access, X_OK},
-	{"-exit", parse_exit},
-	{"-f", parse_f},
-	{"-false", parse_const, false},
-	{"-fls", parse_fls},
-	{"-follow", parse_follow, BFTW_LOGICAL, true},
-	{"-fprint", parse_fprint},
-	{"-fprint0", parse_fprint0},
-	{"-fprintf", parse_fprintf},
-	{"-fstype", parse_fstype},
-	{"-gid", parse_group},
-	{"-group", parse_group},
-	{"-help", parse_help},
-	{"-hidden", parse_hidden},
-	{"-ignore_readdir_race", parse_ignore_races, true},
-	{"-ilname", parse_lname, true},
-	{"-iname", parse_name, true},
-	{"-inum", parse_inum},
-	{"-ipath", parse_path, true},
-	{"-iregex", parse_regex, REG_ICASE},
-	{"-iwholename", parse_path, true},
-	{"-links", parse_links},
-	{"-lname", parse_lname, false},
-	{"-ls", parse_ls},
-	{"-maxdepth", parse_depth_limit, false},
-	{"-mindepth", parse_depth_limit, true},
-	{"-mmin", parse_time, BFS_STAT_MTIME, MINUTES},
-	{"-mnewer", parse_newer, BFS_STAT_MTIME},
-	{"-mount", parse_mount},
-	{"-mtime", parse_time, BFS_STAT_MTIME, DAYS},
-	{"-name", parse_name, false},
-	{"-newer", parse_newer, BFS_STAT_MTIME},
-	{"-newer", parse_newerxy, 0, 0, true},
-	{"-nocolor", parse_color, false},
-	{"-nogroup", parse_nogroup},
-	{"-nohidden", parse_nohidden},
-	{"-noignore_readdir_race", parse_ignore_races, false},
-	{"-noleaf", parse_noleaf},
-	{"-not"},
-	{"-nouser", parse_nouser},
-	{"-nowarn", parse_warn, false},
-	{"-o"},
-	{"-ok", parse_exec, BFS_EXEC_CONFIRM},
-	{"-okdir", parse_exec, BFS_EXEC_CONFIRM | BFS_EXEC_CHDIR},
-	{"-or"},
-	{"-path", parse_path, false},
-	{"-perm", parse_perm},
-	{"-print", parse_print},
-	{"-print0", parse_print0},
-	{"-printf", parse_printf},
-	{"-printx", parse_printx},
-	{"-prune", parse_prune},
-	{"-quit", parse_quit},
-	{"-readable", parse_access, R_OK},
-	{"-regex", parse_regex, 0},
-	{"-regextype", parse_regextype},
-	{"-rm", parse_delete},
-	{"-samefile", parse_samefile},
-	{"-size", parse_size},
-	{"-sparse", parse_sparse},
-	{"-true", parse_const, true},
-	{"-type", parse_type, false},
-	{"-uid", parse_user},
-	{"-unique", parse_unique},
-	{"-used", parse_used},
-	{"-user", parse_user},
-	{"-version", parse_version},
-	{"-warn", parse_warn, true},
-	{"-wholename", parse_path, false},
-	{"-writable", parse_access, W_OK},
-	{"-x", parse_mount},
-	{"-xattr", parse_xattr},
-	{"-xdev", parse_mount},
-	{"-xtype", parse_type, true},
-	{0},
-};
-
-/** Look up an argument in the parse table. */
-static const struct table_entry *table_lookup(const char *arg) {
-	for (const struct table_entry *entry = parse_table; entry->arg; ++entry) {
-		bool match;
-		if (entry->prefix) {
-			match = strncmp(arg, entry->arg, strlen(entry->arg)) == 0;
-		} else {
-			match = strcmp(arg, entry->arg) == 0;
-		}
-		if (match) {
-			return entry;
-		}
-	}
-
-	return NULL;
-}
-
-/** Search for a fuzzy match in the parse table. */
-static const struct table_entry *table_lookup_fuzzy(const char *arg) {
-	const struct table_entry *best = NULL;
-	int best_dist;
-
-	for (const struct table_entry *entry = parse_table; entry->arg; ++entry) {
-		int dist = typo_distance(arg, entry->arg);
-		if (!best || dist < best_dist) {
-			best = entry;
-			best_dist = dist;
-		}
-	}
-
-	return best;
-}
-
-/**
- * LITERAL : OPTION
- *         | TEST
- *         | ACTION
- */
-static struct expr *parse_literal(struct parser_state *state) {
-	// Paths are already skipped at this point
-	const char *arg = state->argv[0];
-
-	if (arg[0] != '-') {
-		goto unexpected;
-	}
-
-	const struct table_entry *match = table_lookup(arg);
-	if (match) {
-		if (match->parse) {
-			goto matched;
-		} else {
-			goto unexpected;
-		}
-	}
-
-	match = table_lookup_fuzzy(arg);
-
-	parse_error(state, "Unknown argument '%s'; did you mean '%s'?", arg, match->arg);
-
-	if (!state->interactive || !match->parse) {
-		fprintf(stderr, "\n");
-		goto unmatched;
-	}
-
-	fprintf(stderr, " ");
-	if (ynprompt() <= 0) {
-		goto unmatched;
-	}
-
-	fprintf(stderr, "\n");
-	state->argv[0] = match->arg;
-
-matched:
-	return match->parse(state, match->arg1, match->arg2);
-
-unmatched:
-	return NULL;
-
-unexpected:
-	parse_error(state, "Expected a predicate; found '%s'.\n", arg);
-	return NULL;
-}
-
-/**
- * FACTOR : "(" EXPR ")"
- *        | "!" FACTOR | "-not" FACTOR
- *        | LITERAL
- */
-static struct expr *parse_factor(struct parser_state *state) {
-	if (skip_paths(state) != 0) {
-		return NULL;
-	}
-
-	const char *arg = state->argv[0];
-	if (!arg) {
-		parse_error(state, "Expression terminated prematurely after '%s'.\n", state->last_arg);
-		return NULL;
-	}
-
-	if (strcmp(arg, "(") == 0) {
-		parser_advance(state, T_OPERATOR, 1);
-
-		struct expr *expr = parse_expr(state);
-		if (!expr) {
-			return NULL;
-		}
-
-		if (skip_paths(state) != 0) {
-			free_expr(expr);
-			return NULL;
-		}
-
-		arg = state->argv[0];
-		if (!arg || strcmp(arg, ")") != 0) {
-			parse_error(state, "Expected a ')' after '%s'.\n", state->argv[-1]);
-			free_expr(expr);
-			return NULL;
-		}
-		parser_advance(state, T_OPERATOR, 1);
-
-		return expr;
-	} else if (strcmp(arg, "!") == 0 || strcmp(arg, "-not") == 0) {
-		char **argv = parser_advance(state, T_OPERATOR, 1);
-
-		struct expr *factor = parse_factor(state);
-		if (!factor) {
-			return NULL;
-		}
-
-		return new_unary_expr(eval_not, factor, argv);
-	} else {
-		return parse_literal(state);
-	}
-}
-
-/**
- * TERM : FACTOR
- *      | TERM FACTOR
- *      | TERM "-a" FACTOR
- *      | TERM "-and" FACTOR
- */
-static struct expr *parse_term(struct parser_state *state) {
-	struct expr *term = parse_factor(state);
-
-	while (term) {
-		if (skip_paths(state) != 0) {
-			free_expr(term);
-			return NULL;
-		}
-
-		const char *arg = state->argv[0];
-		if (!arg) {
-			break;
-		}
-
-		if (strcmp(arg, "-o") == 0 || strcmp(arg, "-or") == 0
-		    || strcmp(arg, ",") == 0
-		    || strcmp(arg, ")") == 0) {
-			break;
-		}
-
-		char **argv = &fake_and_arg;
-		if (strcmp(arg, "-a") == 0 || strcmp(arg, "-and") == 0) {
-			argv = parser_advance(state, T_OPERATOR, 1);
-		}
-
-		struct expr *lhs = term;
-		struct expr *rhs = parse_factor(state);
-		if (!rhs) {
-			free_expr(lhs);
-			return NULL;
-		}
-
-		term = new_binary_expr(eval_and, lhs, rhs, argv);
-	}
-
-	return term;
-}
-
-/**
- * CLAUSE : TERM
- *        | CLAUSE "-o" TERM
- *        | CLAUSE "-or" TERM
- */
-static struct expr *parse_clause(struct parser_state *state) {
-	struct expr *clause = parse_term(state);
-
-	while (clause) {
-		if (skip_paths(state) != 0) {
-			free_expr(clause);
-			return NULL;
-		}
-
-		const char *arg = state->argv[0];
-		if (!arg) {
-			break;
-		}
-
-		if (strcmp(arg, "-o") != 0 && strcmp(arg, "-or") != 0) {
-			break;
-		}
-
-		char **argv = parser_advance(state, T_OPERATOR, 1);
-
-		struct expr *lhs = clause;
-		struct expr *rhs = parse_term(state);
-		if (!rhs) {
-			free_expr(lhs);
-			return NULL;
-		}
-
-		clause = new_binary_expr(eval_or, lhs, rhs, argv);
-	}
-
-	return clause;
-}
-
-/**
- * EXPR : CLAUSE
- *      | EXPR "," CLAUSE
- */
-static struct expr *parse_expr(struct parser_state *state) {
-	struct expr *expr = parse_clause(state);
-
-	while (expr) {
-		if (skip_paths(state) != 0) {
-			free_expr(expr);
-			return NULL;
-		}
-
-		const char *arg = state->argv[0];
-		if (!arg) {
-			break;
-		}
-
-		if (strcmp(arg, ",") != 0) {
-			break;
-		}
-
-		char **argv = parser_advance(state, T_OPERATOR, 1);
-
-		struct expr *lhs = expr;
-		struct expr *rhs = parse_clause(state);
-		if (!rhs) {
-			free_expr(lhs);
-			return NULL;
-		}
-
-		expr = new_binary_expr(eval_comma, lhs, rhs, argv);
-	}
-
-	return expr;
-}
-
-/**
- * Parse the top-level expression.
- */
-static struct expr *parse_whole_expr(struct parser_state *state) {
-	if (skip_paths(state) != 0) {
-		return NULL;
-	}
-
-	struct expr *expr = &expr_true;
-	if (state->argv[0]) {
-		expr = parse_expr(state);
-		if (!expr) {
-			return NULL;
-		}
-	}
-
-	if (state->argv[0]) {
-		parse_error(state, "Unexpected argument '%s'.\n", state->argv[0]);
-		goto fail;
-	}
-
-	if (state->implicit_print) {
-		struct expr *print = new_expr(eval_fprint, 1, &fake_print_arg);
-		if (!print) {
-			goto fail;
-		}
-		init_print_expr(state, print);
-
-		expr = new_binary_expr(eval_and, expr, print, &fake_and_arg);
-		if (!expr) {
-			goto fail;
-		}
-	}
-
-	if (state->warn && state->depth_arg && state->prune_arg) {
-		parse_warning(state, "%s does not work in the presence of %s.\n", state->prune_arg, state->depth_arg);
-
-		if (state->interactive) {
-			fprintf(stderr, "Do you want to continue? ");
-			if (ynprompt() == 0) {
-				goto fail;
-			}
-		}
-
-		fprintf(stderr, "\n");
-	}
-
-	return expr;
-
-fail:
-	free_expr(expr);
-	return NULL;
-}
-
-/**
- * Dump the parsed form of the command line, for debugging.
- */
-void dump_cmdline(const struct cmdline *cmdline, bool verbose) {
-	CFILE *cerr = cmdline->cerr;
-
-	cfprintf(cerr, "${ex}%s${rs} ", cmdline->argv[0]);
-
-	const char *strategy = NULL;
-	switch (cmdline->strategy) {
-	case BFTW_BFS:
-		strategy = "bfs";
-		break;
-	case BFTW_DFS:
-		strategy = "dfs";
-		break;
-	case BFTW_IDS:
-		strategy = "ids";
-		break;
-	}
-	assert(strategy);
-	cfprintf(cerr, "${cyn}-S${rs} ${bld}%s${rs} ", strategy);
-
-	if (cmdline->flags & BFTW_LOGICAL) {
-		cfprintf(cerr, "${cyn}-L${rs} ");
-	} else if (cmdline->flags & BFTW_COMFOLLOW) {
-		cfprintf(cerr, "${cyn}-H${rs} ");
-	} else {
-		cfprintf(cerr, "${cyn}-P${rs} ");
-	}
-
-	if (cmdline->optlevel != 3) {
-		cfprintf(cerr, "${cyn}-O%d${rs} ", cmdline->optlevel);
-	}
-
-	enum debug_flags debug = cmdline->debug;
-	if (debug) {
-		cfprintf(cerr, "${cyn}-D${rs} ");
-		for (int i = 0; debug; ++i) {
-			enum debug_flags flag = debug_flags[i].flag;
-			const char *name = debug_flags[i].name;
-			if ((debug & flag) == flag) {
-				cfprintf(cerr, "${bld}%s${rs}", name);
-				debug ^= flag;
-				if (debug) {
-					cfprintf(cerr, ",");
-				}
-			}
-		}
-		cfprintf(cerr, " ");
-	}
-
-	for (size_t i = 0; i < cmdline->npaths; ++i) {
-		const char *path = cmdline->paths[i];
-		char c = path[0];
-		if (c == '-' || c == '(' || c == ')' || c == '!' || c == ',') {
-			cfprintf(cerr, "${cyn}-f${rs} ");
-		}
-		cfprintf(cerr, "${mag}%s${rs} ", path);
-	}
-
-	if (cmdline->cout->colors) {
-		cfprintf(cerr, "${blu}-color${rs} ");
-	} else {
-		cfprintf(cerr, "${blu}-nocolor${rs} ");
-	}
-	if (cmdline->flags & BFTW_DEPTH) {
-		cfprintf(cerr, "${blu}-depth${rs} ");
-	}
-	if (cmdline->ignore_races) {
-		cfprintf(cerr, "${blu}-ignore_readdir_race${rs} ");
-	}
-	if (cmdline->flags & BFTW_XDEV) {
-		cfprintf(cerr, "${blu}-mount${rs} ");
-	}
-	if (cmdline->mindepth != 0) {
-		cfprintf(cerr, "${blu}-mindepth${rs} ${bld}%d${rs} ", cmdline->mindepth);
-	}
-	if (cmdline->maxdepth != INT_MAX) {
-		cfprintf(cerr, "${blu}-maxdepth${rs} ${bld}%d${rs} ", cmdline->maxdepth);
-	}
-	if (cmdline->unique) {
-		cfprintf(cerr, "${blu}-unique${rs} ");
-	}
-
-	dump_expr(cerr, cmdline->expr, verbose);
-
-	fputs("\n", stderr);
-}
-
-/**
- * Dump the estimated costs.
- */
-static void dump_costs(const struct cmdline *cmdline) {
-	CFILE *cerr = cmdline->cerr;
-	const struct expr *expr = cmdline->expr;
-	cfprintf(cerr, "       Cost: ~${ylw}%g${rs}\n", expr->cost);
-	cfprintf(cerr, "Probability: ~${ylw}%g%%${rs}\n", 100.0*expr->probability);
-}
-
-/**
- * Get the current time.
- */
-static int parse_gettime(struct timespec *ts) {
-#if _POSIX_TIMERS > 0
-	int ret = clock_gettime(CLOCK_REALTIME, ts);
-	if (ret != 0) {
-		perror("clock_gettime()");
-	}
-	return ret;
-#else
-	struct timeval tv;
-	int ret = gettimeofday(&tv, NULL);
-	if (ret == 0) {
-		ts->tv_sec = tv.tv_sec;
-		ts->tv_nsec = tv.tv_usec * 1000L;
-	} else {
-		perror("gettimeofday()");
-	}
-	return ret;
-#endif
-}
-
-/**
- * Parse the command line.
- */
-struct cmdline *parse_cmdline(int argc, char *argv[]) {
-	struct cmdline *cmdline = malloc(sizeof(struct cmdline));
-	if (!cmdline) {
-		perror("malloc()");
-		goto fail;
-	}
-
-	cmdline->argv = NULL;
-	cmdline->paths = NULL;
-	cmdline->npaths = 0;
-	cmdline->colors = NULL;
-	cmdline->cout = NULL;
-	cmdline->cerr = NULL;
-	cmdline->mtab = NULL;
-	cmdline->mtab_error = 0;
-	cmdline->mindepth = 0;
-	cmdline->maxdepth = INT_MAX;
-	cmdline->flags = BFTW_RECOVER;
-	cmdline->strategy = BFTW_BFS;
-	cmdline->optlevel = 3;
-	cmdline->debug = 0;
-	cmdline->xargs_safe = false;
-	cmdline->ignore_races = false;
-	cmdline->unique = false;
-	cmdline->expr = &expr_true;
-	cmdline->nopen_files = 0;
-
-	trie_init(&cmdline->open_files);
-
-	static char* default_argv[] = {"bfs", NULL};
-	if (argc < 1) {
-		argc = 1;
-		argv = default_argv;
-	}
-
-	cmdline->argv = malloc((argc + 1)*sizeof(*cmdline->argv));
-	if (!cmdline->argv) {
-		perror("malloc()");
-		goto fail;
-	}
-	for (int i = 0; i <= argc; ++i) {
-		cmdline->argv[i] = argv[i];
-	}
-
-	enum use_color use_color = COLOR_AUTO;
-	if (getenv("NO_COLOR")) {
-		// https://no-color.org/
-		use_color = COLOR_NEVER;
-	}
-
-	cmdline->colors = parse_colors(getenv("LS_COLORS"));
-	cmdline->cout = cfdup(stdout, use_color ? cmdline->colors : NULL);
-	cmdline->cerr = cfdup(stderr, use_color ? cmdline->colors : NULL);
-	if (!cmdline->cout || !cmdline->cerr) {
-		perror("cfdup()");
-		goto fail;
-	}
-
-	cmdline->mtab = parse_bfs_mtab();
-	if (!cmdline->mtab) {
-		cmdline->mtab_error = errno;
-	}
-
-	bool stdin_tty = isatty(STDIN_FILENO);
-	bool stdout_tty = isatty(STDOUT_FILENO);
-	bool stderr_tty = isatty(STDERR_FILENO);
-
-	struct parser_state state = {
-		.cmdline = cmdline,
-		.argv = cmdline->argv + 1,
-		.command = cmdline->argv[0],
-		.regex_flags = 0,
-		.stdout_tty = stdout_tty,
-		.interactive = stdin_tty && stderr_tty,
-		.use_color = use_color,
-		.implicit_print = true,
-		.warn = stdin_tty,
-		.non_option_seen = false,
-		.just_info = false,
-		.last_arg = NULL,
-		.depth_arg = NULL,
-		.prune_arg = NULL,
-	};
-
-	if (strcmp(xbasename(state.command), "find") == 0) {
-		// Operate depth-first when invoked as "find"
-		cmdline->strategy = BFTW_DFS;
-	}
-
-	if (parse_gettime(&state.now) != 0) {
-		goto fail;
-	}
-
-	cmdline->expr = parse_whole_expr(&state);
-	if (!cmdline->expr) {
-		if (state.just_info) {
-			goto done;
-		} else {
-			goto fail;
-		}
-	}
-
-	if (optimize_cmdline(cmdline) != 0) {
-		goto fail;
-	}
-
-	if (cmdline->npaths == 0) {
-		if (parse_root(&state, ".") != 0) {
-			goto fail;
-		}
-	}
-
-	if ((cmdline->flags & BFTW_LOGICAL) && !cmdline->unique) {
-		// We need bftw() to detect cycles unless -unique does it for us
-		cmdline->flags |= BFTW_DETECT_CYCLES;
-	}
-
-	if (cmdline->debug & DEBUG_TREE) {
-		dump_cmdline(cmdline, false);
-	}
-	if (cmdline->debug & DEBUG_COST) {
-		dump_costs(cmdline);
-	}
-
-done:
-	return cmdline;
-
-fail:
-	free_cmdline(cmdline);
-	return NULL;
-}