cmus/file_load.c

   1 /*
   2  * Copyright 2004 Timo Hirvonen
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * 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, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  17  * 02111-1307, USA.
  18  */
  19
  20 #include <file_load.h>
  21 #include <xmalloc.h>
  22
  23 #include <unistd.h>
  24 #include <fcntl.h>
  25 #include <string.h>
  26 #include <errno.h>
  27
  28 int file_load(const char *filename,
  29                 void (*handle_line)(void *data, const char *line), void *data)
  30 {
  31         char *buffer;
  32         size_t buffer_size = 4096;
  33         int pos = 0;
  34         int fd;
  35
  36         fd = open(filename, O_RDONLY);
  37         if (fd == -1)
  38                 return -1;
  39         buffer = xnew(char, buffer_size);
  40         while (1) {
  41                 int i, start, len, rc;
  42
  43                 rc = read(fd, buffer + pos, buffer_size - pos);
  44                 if (rc == -1) {
  45                         int save = errno;
  46
  47                         free(buffer);
  48                         close(fd);
  49                         errno = save;
  50                         return -1;
  51                 }
  52                 if (rc == 0) {
  53                         if (pos > 0) {
  54                                 /* handle line without '\n' */
  55                                 buffer[pos] = 0;
  56                                 handle_line(data, buffer);
  57                         }
  58                         free(buffer);
  59                         close(fd);
  60                         return 0;
  61                 }
  62                 start = 0;
  63                 len = pos + rc;
  64                 i = 0;
  65                 while (i < len) {
  66                         if (buffer[start + i] == '\n') {
  67                                 buffer[start + i] = 0;
  68                                 handle_line(data, buffer + start);
  69                                 start += i + 1;
  70                                 len -= i + 1;
  71                                 i = 0;
  72                         } else {
  73                                 i++;
  74                         }
  75                 }
  76                 if (start == 0) {
  77                         /* line doesn't fit into the buffer */
  78                         buffer_size *= 2;
  79                         buffer = xrenew(char, buffer, buffer_size);
  80                 } else if (len) {
  81                         /* len - start bytes left */
  82                         memmove(buffer, buffer + start, len);
  83                 }
  84                 pos = len;
  85         }
  86 }