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-rw-r--r--regex.c124
1 files changed, 0 insertions, 124 deletions
diff --git a/regex.c b/regex.c
deleted file mode 100644
index 02a58fa..0000000
--- a/regex.c
+++ /dev/null
@@ -1,124 +0,0 @@
-#include <stdio.h>
-#include <string.h>
-
-#include "ast.h"
-
-static const int precedence[ATOM_MAX] = {
- [ATOM_ALPHABETIC] = 1,
- [ATOM_NUMERIC] = 1,
- [ATOM_UPPERCASE] = 1,
- [ATOM_LOWERCASE] = 1,
- [ATOM_CONTROL] = 1,
- [ATOM_PUNCTUATION] = 1,
- [ATOM_EVERYTHING] = 1,
- [ATOM_REPETITION] = 2,
- [ATOM_SEQUENCE] = 3,
- [ATOM_LITERAL] = 3,
- [ATOM_ALTERNATION] = 4,
-};
-
-static void print_repeat(const struct repeat *r)
-{
- if (r->max < 0) {
- switch (r->min) {
- case 0: printf("*"); break;
- case 1: printf("+"); break;
- default: printf("{%ld,}", r->min); break;
- }
- } else if (r->min == 0 && r->max == 1) {
- printf("?");
- } else if (r->min == r->max) {
- printf("{%ld}", r->min);
- } else {
- printf("{%ld,%ld}", r->min, r->max);
- }
-}
-
-static void print_literal(const char *s)
-{
- for (; *s; s++) {
- switch (*s) {
- case '.':
- case '[':
- case '{':
- case '}':
- case '(':
- case ')':
- case '\\':
- case '*':
- case '+':
- case '?':
- case '|':
- case '^':
- case '$':
- putchar('\\');
-
- default:
- putchar(*s);
- }
- }
-}
-
-static int get_precedence(const struct atom *a)
-{
- if (a->type == ATOM_LITERAL) {
- switch (strlen(a->u.literal)) {
- case 0: return -1;
- case 1: return precedence[ATOM_EVERYTHING];
- default: return precedence[ATOM_SEQUENCE];
- }
- }
-
- return precedence[a->type];
-}
-
-static void print_atom(const struct atom *a);
-
-static void print_child_atom(const struct atom *child, const struct atom *parent)
-{
- int group = get_precedence(child) > get_precedence(parent);
- if (group) printf("(");
- print_atom(child);
- if (group) printf(")");
-}
-
-static void print_atom(const struct atom *a)
-{
- switch (a->type) {
- case ATOM_ALTERNATION:
- print_child_atom(a->u.children[0], a);
- printf("|");
- print_child_atom(a->u.children[1], a);
- break;
-
- case ATOM_SEQUENCE:
- print_child_atom(a->u.children[0], a);
- print_child_atom(a->u.children[1], a);
- break;
-
- case ATOM_REPETITION:
- print_child_atom(a->u.repeat.child, a);
- print_repeat(&a->u.repeat.counts);
- break;
-
- case ATOM_LITERAL:
- print_literal(a->u.literal);
- break;
-
- case ATOM_ALPHABETIC: printf("[:alpha:]"); break;
- case ATOM_NUMERIC: printf("[:digit:]"); break;
- case ATOM_UPPERCASE: printf("[:upper:]"); break;
- case ATOM_LOWERCASE: printf("[:lower:]"); break;
- case ATOM_CONTROL: printf("[:cntrl:]"); break;
- case ATOM_PUNCTUATION: printf("[:punct:]"); break;
- case ATOM_EVERYTHING: printf("."); break;
- }
-}
-
-void print_regex(const struct atom *a)
-{
- printf("^");
- print_atom(a);
- printf("$\n");
-}
-