Merge pull request #37 from zoziha/add_readline

Add readline

Author: zoziha

fpm.toml

@@ -41,6 +41,10 @@ main = "test_io_file.f90"
 name = "io_color"
 source-dir = "test/io"
 main = "test_io_color.f90"
+[[test]]
+name = "io_read_line"
+source-dir = "test/io"
+main = "test_io_read_line.f90"
 
 ## [linalg] tests
 [[test]]

meta-src/forlab_io.fypp

@@ -18,6 +18,8 @@ module forlab_io
     public :: disp
 
     public :: progress_bar, progress_perc
+    
+    public :: read_line, read_file
 
     !> Version: experimental
     !> 
@@ -187,6 +189,20 @@ module forlab_io
         end subroutine progress_perc_${k1}$
         #:endfor
     end interface progress_perc
+    
+    interface
+        module subroutine read_line(line, unit, iostat)
+            character(:), allocatable, intent(out) :: line
+            integer, intent(in), optional :: unit
+            integer, intent(out), optional :: iostat
+        end subroutine read_line
+        module subroutine read_file(string, file, iostat, keep_newline)
+            character(:), allocatable, intent(out) :: string
+            character(*), intent(in) :: file
+            integer, intent(out), optional :: iostat
+            logical, intent(in), optional :: keep_newline
+        end subroutine read_file
+    end interface
 
 contains
 

src/forlab_io.f90

@@ -18,6 +18,8 @@ module forlab_io
 
     public :: progress_bar, progress_perc
 
+    public :: read_line, read_file
+
     !> Version: experimental
     !>
     !> forlab file derived type.
@@ -637,6 +639,20 @@ module subroutine progress_perc_int64(iter, itermax, prefix)
         end subroutine progress_perc_int64
     end interface progress_perc
 
+    interface
+        module subroutine read_line(line, unit, iostat)
+            character(:), allocatable, intent(out) :: line
+            integer, intent(in), optional :: unit
+            integer, intent(out), optional :: iostat
+        end subroutine read_line
+        module subroutine read_file(string, file, iostat, keep_newline)
+            character(:), allocatable, intent(out) :: string
+            character(*), intent(in) :: file
+            integer, intent(out), optional :: iostat
+            logical, intent(in), optional :: keep_newline
+        end subroutine read_file
+    end interface
+
 contains
 
     !> Version: experimental

src/forlab_io_read_line.f90

@@ -0,0 +1,64 @@
+submodule (forlab_io) forlab_io_read_line
+
+    use, intrinsic :: iso_fortran_env, only: stdin => input_unit
+    implicit none
+    character(*), parameter :: nl = new_line("\n")
+    
+contains
+
+    !> Read a line from the input unit.
+    subroutine read_line(line, unit, iostat)
+    
+        character(:), allocatable, intent(out) :: line
+        integer, intent(in), optional :: unit
+        integer, intent(out), optional :: iostat
+        
+        integer :: unit_, iostat_
+        character(len=512) :: line_
+        character(len=512) :: msg
+        
+        unit_ = optval(unit, stdin)
+        
+        line = ""
+        read(unit_, "(A512)", iostat=iostat_, iomsg=msg) line_
+        if (present(iostat)) then
+            iostat = iostat_
+            if (iostat_ == 0) line = trim(line_)
+        else
+            if (iostat_ == 0) then
+                line = trim(line_)
+            else
+                error stop msg
+            end if
+        end if        
+    
+    end subroutine read_line
+    
+    !> Read ASCII file as a string.
+    subroutine read_file(string, file, iostat, keep_newline)
+        
+        character(:), allocatable, intent(out) :: string
+        character(*), intent(in) :: file
+        integer, intent(out), optional :: iostat
+        logical, intent(in), optional :: keep_newline
+        
+        integer :: iostat_, unit, count, i
+        character(:), allocatable :: string_
+        character(len=512) :: msg
+        logical :: keep_newline_
+        
+        keep_newline_ = optval(keep_newline, .true.)
+        open(newunit=unit, file=file)
+        
+        string = ""
+        count = countlines(file)
+        do i = 1, count
+            call read_line(string_, unit, iostat_)
+            if (keep_newline_) string_ = string_ // nl
+            string = string//string_
+        end do
+        close(unit)
+        
+    end subroutine read_file
+
+end submodule forlab_io_read_line

test/io/test_io_read_line.f90

@@ -0,0 +1,18 @@
+program main
+
+    use forlab_io, only: read_line, read_file
+    implicit none
+    integer :: unit
+    character(:), allocatable :: line
+    
+    open(newunit=unit, file="test/io/test_io_read_line.f90")
+    call read_line(line, unit)
+    print *, line, len(line)
+    
+    call read_file(line, "test/io/test_io_read_line.f90")
+    print *, line, len(line)
+    
+    call read_file(line, "test/io/test_io_read_line.f90", keep_newline=.false.)
+    print *, line, len(line)
+
+end program main