1  /* Reading file lists.
       2     Copyright (C) 1995-1998, 2000-2002, 2007, 2019 Free Software Foundation, Inc.
       3  
       4     This program is free software: you can redistribute it and/or modify
       5     it under the terms of the GNU General Public License as published by
       6     the Free Software Foundation; either version 3 of the License, or
       7     (at your option) any later version.
       8  
       9     This program is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      12     GNU General Public License for more details.
      13  
      14     You should have received a copy of the GNU General Public License
      15     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      16  
      17  #ifdef HAVE_CONFIG_H
      18  # include "config.h"
      19  #endif
      20  
      21  /* Specification.  */
      22  #include "file-list.h"
      23  
      24  #include <errno.h>
      25  #include <stdio.h>
      26  #include <stdlib.h>
      27  #include <string.h>
      28  
      29  #include "str-list.h"
      30  #include "error.h"
      31  #include "gettext.h"
      32  
      33  /* A convenience macro.  I don't like writing gettext() every time.  */
      34  #define _(str) gettext (str)
      35  
      36  
      37  /* Read list of filenames from a file.  */
      38  string_list_ty *
      39  read_names_from_file (const char *file_name)
      40  {
      41    size_t line_len = 0;
      42    char *line_buf = NULL;
      43    FILE *fp;
      44    string_list_ty *result;
      45  
      46    if (strcmp (file_name, "-") == 0)
      47      fp = stdin;
      48    else
      49      {
      50        fp = fopen (file_name, "r");
      51        if (fp == NULL)
      52          error (EXIT_FAILURE, errno,
      53                 _("error while opening \"%s\" for reading"), file_name);
      54      }
      55  
      56    result = string_list_alloc ();
      57  
      58    while (!feof (fp))
      59      {
      60        /* Read next line from file.  */
      61        int len = getline (&line_buf, &line_len, fp);
      62  
      63        /* In case of an error leave loop.  */
      64        if (len < 0)
      65          break;
      66  
      67        /* Remove trailing '\n' and trailing whitespace.  */
      68        if (len > 0 && line_buf[len - 1] == '\n')
      69          line_buf[--len] = '\0';
      70        while (len > 0
      71               && (line_buf[len - 1] == ' '
      72                   || line_buf[len - 1] == '\t'
      73                   || line_buf[len - 1] == '\r'))
      74          line_buf[--len] = '\0';
      75  
      76        /* Test if we have to ignore the line.  */
      77        if (!(*line_buf == '\0' || *line_buf == '#'))
      78          /* Include the line in the result.  */
      79          string_list_append_unique (result, line_buf);
      80      }
      81  
      82    /* Free buffer allocated through getline.  */
      83    if (line_buf != NULL)
      84      free (line_buf);
      85  
      86    /* Close input stream.  */
      87    if (fp != stdin)
      88      fclose (fp);
      89  
      90    return result;
      91  }