diff options
Diffstat (limited to 'src/expr.h')
-rw-r--r-- | src/expr.h | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/src/expr.h b/src/expr.h new file mode 100644 index 0000000..7bcace7 --- /dev/null +++ b/src/expr.h @@ -0,0 +1,247 @@ +// Copyright © Tavian Barnes <tavianator@tavianator.com> +// SPDX-License-Identifier: 0BSD + +/** + * The expression tree representation. + */ + +#ifndef BFS_EXPR_H +#define BFS_EXPR_H + +#include "prelude.h" +#include "color.h" +#include "eval.h" +#include "stat.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 linked list of expressions. + */ +struct bfs_exprs { + struct bfs_expr *head; + struct bfs_expr **tail; +}; + +/** + * A command line expression. + */ +struct bfs_expr { + /** This expression's next sibling, if any. */ + struct bfs_expr *next; + /** The next allocated expression. */ + struct { struct bfs_expr *next; } freelist; + + /** 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 uses stat(). */ + bool calls_stat; + + /** 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 bfs_exprs children; + + /** Integer comparisons. */ + struct { + /** Integer for this comparison. */ + long long num; + /** The comparison mode. */ + enum bfs_int_cmp int_cmp; + + /** -size data. */ + enum bfs_size_unit size_unit; + + /** The stat field to look at. */ + enum bfs_stat_field stat_field; + /** The time unit. */ + enum bfs_time_unit time_unit; + /** The reference time. */ + struct timespec reftime; + }; + + /** String comparisons. */ + struct { + /** String pattern. */ + const char *pattern; + /** fnmatch() flags. */ + int fnm_flags; + /** Whether strcmp() can be used instead of fnmatch(). */ + bool literal; + }; + + /** Printing actions. */ + struct { + /** The output stream. */ + CFILE *cfile; + /** Optional file path. */ + const char *path; + /** 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; + }; + }; +}; + +struct bfs_ctx; + +/** + * Create a new expression. + */ +struct bfs_expr *bfs_expr_new(struct bfs_ctx *ctx, bfs_eval_fn *eval, size_t argc, char **argv); + +/** + * @return Whether this type of expression has children. + */ +bool bfs_expr_is_parent(const struct bfs_expr *expr); + +/** + * @return The first child of this expression, or NULL if it has none. + */ +struct bfs_expr *bfs_expr_children(const struct bfs_expr *expr); + +/** + * Add a child to an expression. + */ +void bfs_expr_append(struct bfs_expr *expr, struct bfs_expr *child); + +/** + * Add a list of children to an expression. + */ +void bfs_expr_extend(struct bfs_expr *expr, struct bfs_exprs *children); + +/** + * @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 any resources owned by an expression. + */ +void bfs_expr_clear(struct bfs_expr *expr); + +#endif // BFS_EXPR_H |