morenice / ahocorasick

C implementation Aho-Corasick string matching

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ahocorasick's Issues

new segment fault on a test case

PR #6 is incomplete fix.
This make new segment fault case, unfortunately.

Missing matching texts

The engine does not locate all texts:
in sample_code():
If you add:
aho_add_match_text(&aho, "b", 1);
The text "b" will not be located.

It seems the code will return only return one result for each last matching letter

Additional example:
aho_add_match_text(&aho, "dab", 3);
The code wil not return a match for "ab" anymore

How can I access the machine states?

I want to check if there is a goto transition between state s and state t for some input character a.

Also if there is a failure transition from some state s to state t.

seg fault on sample_code3

variable id set but not used

What is the purpose of id? How do you use it?
src/main.c: In function ‘sample_code’: src/main.c:29:9: warning: variable ‘id’ set but not used [-Wunused-but-set-variable] 29 | int id[10] = {0}; | ^~ src/main.c: In function ‘sample_code2’: src/main.c:50:9: warning: variable ‘id’ set but not used [-Wunused-but-set-variable] 50 | int id[10] = {0}; | ^~ src/main.c: In function ‘sample_code3’: src/main.c:73:9: warning: variable ‘id’ set but not used [-Wunused-but-set-variable] 73 | int id[10] = {0}; | ^~ src/main.c: In function ‘sample_code_bench_file’: src/main.c:97:9: warning: variable ‘id’ set but not used [-Wunused-but-set-variable] 97 | int id[10] = {0}; | ^~ src/main.c: In function ‘sample_code_thread’: src/main.c:143:9: warning: variable ‘id’ set but not used [-Wunused-but-set-variable] 143 | int id[10] = {0}; | ^~

Seg fault on a test case

text: Lorem ipsum dolor sit amet, consectetur brown elit. Proin vehicula brown egestas. Aliquam a dui tincidunt, elementum sapien in, ultricies lacus. Phasellus congue, sapien nec

match text:
consectetur
Proin
egestasAliquam
elementum
ultricies
vehicula

Added a PR which replicates this issue: #1

aho_del_match_text will crash on free(iter->text)

iter->text may be constant which are not allocated from the heap

different result to fgrep

$ time ./ahocorasick
280503
./ahocorasick  1.29s user 0.08s system 99% cpu 1.364 total
$ time fgrep -c -e 1984 -e 1985 googlebooks-eng-all-1gram-20120701-0
280457
fgrep -c -e 1984 -e 1985 googlebooks-eng-all-1gram-20120701-0  9.76s user 0.06s system 99% cpu 9.846 total