A work-in-progress collection of Fortran 2018 ISO_C_BINDING interfaces to Perl-compatible Regular Expressions 2 (PCRE2). The library is also available on MacPorts.
You will need libpcre2 with development headers. On FreeBSD, run:
# pkg install devel/pcre2
On Debian Linux, install:
# apt-get install libpcre2-8-0 libpcre2-dev
Clone the repository and execute the provided Makefile
to create the static
library libfortran-pcre2.a
containing the interfaces:
$ git clone https://github.com/interkosmos/fortran-pcre2
$ cd fortran-pcre2/
$ make
Install the library and the modules files system-wide to /opt
:
$ make install PREFIX=/opt
Instead of make
, you may want to build the library using the Fortran Package
Manager:
$ fpm build --profile release
Link your Fortran programs against libfortran-pcre2.a
and -lpcre2-8
.
The following program just compiles and executes a basic regular expression.
! example.f90
program main
use, intrinsic :: iso_c_binding
use :: pcre2
implicit none (type, external)
integer, parameter :: OVECSIZE = 30 ! Must be multiple of 3.
character(len=128) :: buffer
character(len=:), allocatable :: pattern, subject
integer :: err_code, rc
integer(kind=pcre2_size) :: err_offset
type(c_ptr) :: match_data, re
pattern = '^([A-Z][a-z]+)$'
subject = 'Fortran'
! Compile regular expression.
re = pcre2_compile(pattern = pattern, &
length = len(pattern, kind=pcre2_size), &
options = 0, &
errorcode = err_code, &
erroroffset = err_offset, &
ccontext = c_null_ptr)
if (.not. c_associated(re)) then
buffer = ' '
rc = pcre2_get_error_message(err_code, buffer, len(buffer, kind=pcre2_size))
print '("Error ", i0, ": ", a)', err_code, trim(buffer)
stop
end if
! Execute regular expression.
match_data = pcre2_match_data_create(OVECSIZE, c_null_ptr)
rc = pcre2_match(code = re, &
subject = subject, &
length = len(subject, kind=pcre2_size), &
startoffset = int(0, kind=pcre2_size), &
options = 0, &
match_data = match_data, &
mcontext = c_null_ptr)
if (rc == 0) then
print '("OVECSIZE too small")'
else if (rc < 0) then
select case (rc)
case (PCRE2_ERROR_NOMATCH)
print '("No match")'
case default
print '("Matching error ", i0)', rc
end select
else if (rc > 0) then
print '("Match!")'
end if
call pcre2_match_data_free(match_data)
call pcre2_code_free(re)
end program main
If the library has been installed to /opt
, then compile, link, and run the
program with:
$ gfortran -I/opt/include/libfortran-pcre2 -o example example.f90 /opt/lib/libfortran-pcre2.a -lpcre2-8
$ ./example
You can add fortran-pcre2 as an FPM dependency:
[dependencies]
fortran-pcre2 = { git = "https://github.com/interkosmos/fortran-pcre2.git" }
It is not necessary to null-terminate character strings given to the procedures
of fortran-pcre2. In contrast to the C API of PCRE2, you must not free
substrings with pcre2_substring_free()
, as this will be done by the wrapper
functions.
C API | Fortran interface |
---|---|
pcre2_code_free_8 |
pcre2_code_free |
pcre2_compile_8 |
pcre2_compile |
pcre2_compile_context_free_8 |
pcre2_compile_context_free |
pcre2_get_error_message_8 |
pcre2_get_error_message |
pcre2_get_ovector_count_8 |
pcre2_get_ovector_count |
pcre2_get_ovector_pointer_8 |
pcre2_get_ovector_pointer |
pcre2_match_8 |
pcre2_match |
pcre2_match_data_create_8 |
pcre2_match_data_create |
pcre2_match_data_free_8 |
pcre2_match_data_free |
pcre2_substring_copy_byname_8 |
pcre2_substring_copy_byname |
pcre2_substring_copy_bynumber_8 |
pcre2_substring_copy_bynumber |
pcre2_substring_free_8 |
pcre2_substring_free |
pcre2_substring_get_byname_8 |
pcre2_substring_get_byname |
pcre2_substring_get_bynumber_8 |
pcre2_substring_get_bynumber |
pcre2_substring_number_from_name_8 |
pcre2_substring_number_from_name |
ISC