contrib/android/block_range.c

   1 #define _GNU_SOURCE
   2
   3 #include "block_range.h"
   4 #include <stdio.h>
   5
   6 struct block_range *new_block_range(blk64_t start, blk64_t end)
   7 {
   8         struct block_range *range = malloc(sizeof(*range));
   9         range->start = start;
  10         range->end = end;
  11         range->next = NULL;
  12         return range;
  13 }
  14
  15 void add_blocks_to_range(struct block_range_list *list, blk64_t blk_start,
  16                          blk64_t blk_end)
  17 {
  18         if (list->head == NULL)
  19                 list->head = list->tail = new_block_range(blk_start, blk_end);
  20         else if (list->tail->end + 1 == blk_start)
  21                 list->tail->end += (blk_end - blk_start + 1);
  22         else {
  23                 struct block_range *range = new_block_range(blk_start, blk_end);
  24                 list->tail->next = range;
  25                 list->tail = range;
  26         }
  27 }
  28
  29 static void remove_head(struct block_range_list *list)
  30 {
  31         struct block_range *next_range = list->head->next;
  32
  33         free(list->head);
  34         if (next_range == NULL)
  35                 list->head = list->tail = NULL;
  36         else
  37                 list->head = next_range;
  38 }
  39
  40 void delete_block_ranges(struct block_range_list *list)
  41 {
  42         while (list->head)
  43                 remove_head(list);
  44 }
  45
  46 int write_block_ranges(FILE *f, struct block_range *range,
  47                                      char *sep)
  48 {
  49         int len;
  50         char *buf;
  51
  52         while (range) {
  53                 if (range->start == range->end)
  54                         len = asprintf(&buf, "%llu%s", range->start, sep);
  55                 else
  56                         len = asprintf(&buf, "%llu-%llu%s", range->start,
  57                                        range->end, sep);
  58                 if (fwrite(buf, 1, len, f) != (size_t)len) {
  59                         free(buf);
  60                         return -1;
  61                 }
  62                 free(buf);
  63                 range = range->next;
  64         }
  65
  66         len = strlen(sep);
  67         if (fseek(f, -len, SEEK_CUR) == -len)
  68                 return -1;
  69         return 0;
  70 }
  71
  72 blk64_t consume_next_block(struct block_range_list *list)
  73 {
  74         blk64_t ret = list->head->start;
  75
  76         list->head->start += 1;
  77         if (list->head->start > list->head->end)
  78                 remove_head(list);
  79         return ret;
  80 }