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Diffstat (limited to 'src/expr.h')
| -rw-r--r-- | src/expr.h | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/src/expr.h b/src/expr.h new file mode 100644 index 0000000..1f1ece6 --- /dev/null +++ b/src/expr.h @@ -0,0 +1,235 @@ +/**************************************************************************** + * bfs * + * Copyright (C) 2015-2022 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 expression tree representation. + */ + +#ifndef BFS_EXPR_H +#define BFS_EXPR_H + +#include "color.h" +#include "eval.h" +#include "stat.h" +#include <stdbool.h> +#include <stddef.h> +#include <sys/types.h> +#include <time.h> + +/** + * Integer comparison modes. + */ +enum bfs_int_cmp { + /** Exactly N. */ + BFS_INT_EQUAL, + /** Less than N (-N). */ + BFS_INT_LESS, + /** Greater than N (+N). */ + BFS_INT_GREATER, +}; + +/** + * Permission comparison modes. + */ +enum bfs_mode_cmp { + /** Mode is an exact match (MODE). */ + BFS_MODE_EQUAL, + /** Mode has all these bits (-MODE). */ + BFS_MODE_ALL, + /** Mode has any of these bits (/MODE). */ + BFS_MODE_ANY, +}; + +/** + * Possible time units. + */ +enum bfs_time_unit { + /** Seconds. */ + BFS_SECONDS, + /** Minutes. */ + BFS_MINUTES, + /** Days. */ + BFS_DAYS, +}; + +/** + * Possible file size units. + */ +enum bfs_size_unit { + /** 512-byte blocks. */ + BFS_BLOCKS, + /** Single bytes. */ + BFS_BYTES, + /** Two-byte words. */ + BFS_WORDS, + /** Kibibytes. */ + BFS_KB, + /** Mebibytes. */ + BFS_MB, + /** Gibibytes. */ + BFS_GB, + /** Tebibytes. */ + BFS_TB, + /** Pebibytes. */ + BFS_PB, +}; + +/** + * A command line expression. + */ +struct bfs_expr { + /** The function that evaluates this expression. */ + bfs_eval_fn *eval_fn; + + /** The number of command line arguments for this expression. */ + size_t argc; + /** The command line arguments comprising this expression. */ + char **argv; + + /** The number of files this expression keeps open between evaluations. */ + int persistent_fds; + /** The number of files this expression opens during evaluation. */ + int ephemeral_fds; + + /** Whether this expression has no side effects. */ + bool pure; + /** Whether this expression always evaluates to true. */ + bool always_true; + /** Whether this expression always evaluates to false. */ + bool always_false; + /** Whether this expression doesn't appear on the command line. */ + bool synthetic; + + /** Estimated cost. */ + float cost; + /** Estimated probability of success. */ + float probability; + /** Number of times this predicate was evaluated. */ + size_t evaluations; + /** Number of times this predicate succeeded. */ + size_t successes; + /** Total time spent running this predicate. */ + struct timespec elapsed; + + /** Auxilliary data for the evaluation function. */ + union { + /** Child expressions. */ + struct { + /** The left hand side of the expression. */ + struct bfs_expr *lhs; + /** The right hand side of the expression. */ + struct bfs_expr *rhs; + }; + + /** Integer comparisons. */ + struct { + /** Integer for this comparison. */ + long long num; + /** The comparison mode. */ + enum bfs_int_cmp int_cmp; + + /** Optional extra data. */ + union { + /** -size data. */ + enum bfs_size_unit size_unit; + + /** Timestamp comparison data. */ + struct { + /** The stat field to look at. */ + enum bfs_stat_field stat_field; + /** The reference time. */ + struct timespec reftime; + /** The time unit. */ + enum bfs_time_unit time_unit; + }; + }; + }; + + /** Printing actions. */ + struct { + /** The output stream. */ + CFILE *cfile; + /** Optional -printf format. */ + struct bfs_printf *printf; + }; + + /** -exec data. */ + struct bfs_exec *exec; + + /** -flags data. */ + struct { + /** The comparison mode. */ + enum bfs_mode_cmp flags_cmp; + /** Flags that should be set. */ + unsigned long long set_flags; + /** Flags that should be cleared. */ + unsigned long long clear_flags; + }; + + /** -perm data. */ + struct { + /** The comparison mode. */ + enum bfs_mode_cmp mode_cmp; + /** Mode to use for files. */ + mode_t file_mode; + /** Mode to use for directories (different due to X). */ + mode_t dir_mode; + }; + + /** -regex data. */ + struct bfs_regex *regex; + + /** -samefile data. */ + struct { + /** Device number of the target file. */ + dev_t dev; + /** Inode number of the target file. */ + ino_t ino; + }; + }; +}; + +/** Singleton true expression instance. */ +extern struct bfs_expr bfs_true; +/** Singleton false expression instance. */ +extern struct bfs_expr bfs_false; + +/** + * Create a new expression. + */ +struct bfs_expr *bfs_expr_new(bfs_eval_fn *eval, size_t argc, char **argv); + +/** + * @return Whether the expression has child expressions. + */ +bool bfs_expr_has_children(const struct bfs_expr *expr); + +/** + * @return Whether expr is known to always quit. + */ +bool bfs_expr_never_returns(const struct bfs_expr *expr); + +/** + * @return The result of the integer comparison for this expression. + */ +bool bfs_expr_cmp(const struct bfs_expr *expr, long long n); + +/** + * Free an expression tree. + */ +void bfs_expr_free(struct bfs_expr *expr); + +#endif // BFS_EXPR_H |