ialloc.c

   1 #include <stdio.h>
   2 #include <malloc.h>
   3
   4 #include "tfs.h"
   5
   6
   7 static void * tfs_read_inode_bitmap(struct tfs_sb_info *sbi)
   8 {
   9         char *buf = malloc(sbi->s_block_size);
  10
  11         tfs_bread(sbi, sbi->s_inode_bitmap, buf);
  12
  13         return buf;
  14 }
  15
  16 /*
  17  * free an inode, return -1 if failed, or return 9
  18  */
  19 int tfs_free_inode(struct tfs_sb_info *sbi, int inr)
  20 {
  21         char *bitmap = tfs_read_inode_bitmap(sbi);
  22
  23         /* inode number count from 1 */
  24         if (clear_bit(bitmap, inr - 1) == 0) {
  25                 printf("ERROR: trying to free an unallocated inode!\n");
  26                 free(bitmap);
  27                 return -1;
  28         }
  29
  30         tfs_bwrite(sbi, sbi->s_inode_bitmap, bitmap);
  31         free(bitmap);
  32         return 0;
  33 }
  34
  35 int tfs_alloc_inode(struct tfs_sb_info *sbi, int inr)
  36 {
  37         char *bitmap;
  38
  39         if (inr < 0) {
  40                 printf("ERROR: trying to alloc a negtive inode!\n");
  41                 return -1;
  42         }
  43
  44         bitmap = tfs_read_inode_bitmap(sbi);
  45         /* try the target first */
  46         if (test_bit(bitmap, inr - 1) != 0)
  47                 inr = find_first_zero(bitmap, bitmap + sbi->s_block_size) + 1;
  48         if (inr != -1) {
  49                 set_bit(bitmap, inr - 1);
  50                 tfs_bwrite(sbi, sbi->s_inode_bitmap, bitmap);
  51         }
  52
  53         free(bitmap);
  54         return inr;
  55 }
  56
  57 #if 0  /* the deubg part */
  58 #include <stdlib.h>
  59 int main(int argc, char *argv[])
  60 {
  61         int i;
  62         int inr;
  63         struct tfs_sb_info *sbi;
  64         char *fs = argv[1];
  65         char *command = argv[2];
  66         char **inodes = argv + 3;
  67         int count = argc - 3;
  68
  69         if (argc < 4) {
  70                 printf("Usage: ialloc tfs.img command inodes...\n");
  71                 printf("       alloc, to alloc inodes\n");
  72                 printf("       feee,  to free inodes\n");
  73                 return 1;
  74         }
  75
  76         sbi = tfs_mount_by_fsname(fs);
  77         if (!sbi) {
  78                 printf("tfs mount failed!\n");
  79                 return 1;
  80         }
  81
  82         if (strcmp(command, "alloc") == 0) {
  83                 for (i = 0; i <  count; i++) {
  84                         inr = atoi(inodes[i]);
  85                         printf("trying to alloc inode %u\n", inr);
  86                         inr = tfs_alloc_inode(sbi, inr);
  87                         printf("inode number: %u allocated\n", inr);
  88                 }
  89         } else if (strcmp(command, "free") == 0) {
  90                 for (i = 0; i < count; i++) {
  91                         inr = atoi(inodes[i]);
  92                         printf("trying to free inode %u\n", inr);
  93                         inr = tfs_free_inode(sbi, inr);
  94                         printf("inode number: %d freed\n", inr);
  95                 }
  96         } else {
  97                 printf("Unknown command!\n");
  98         }
  99
 100         return 0;
 101 }
 102 #endif