e2fsck/dx_dirinfo.c

   1 /*
   2  * dirinfo.c --- maintains the directory information table for e2fsck.
   3  *
   4  * Copyright (C) 1993 Theodore Ts'o.  This file may be redistributed
   5  * under the terms of the GNU Public License.
   6  */
   7
   8 #include "config.h"
   9 #include "e2fsck.h"
  10 #ifdef ENABLE_HTREE
  11
  12 /*
  13  * This subroutine is called during pass1 to create a directory info
  14  * entry.  During pass1, the passed-in parent is 0; it will get filled
  15  * in during pass2.
  16  */
  17 void e2fsck_add_dx_dir(e2fsck_t ctx, ext2_ino_t ino, int num_blocks)
  18 {
  19         struct dx_dir_info *dir;
  20         int             i, j;
  21         errcode_t       retval;
  22         unsigned long   old_size;
  23
  24 #if 0
  25         printf("add_dx_dir_info for inode %lu...\n", ino);
  26 #endif
  27         if (!ctx->dx_dir_info) {
  28                 ctx->dx_dir_info_count = 0;
  29                 ctx->dx_dir_info_size = 100; /* Guess */
  30                 ctx->dx_dir_info  = (struct dx_dir_info *)
  31                         e2fsck_allocate_memory(ctx, ctx->dx_dir_info_size
  32                                                * sizeof (struct dx_dir_info),
  33                                                "directory map");
  34         }
  35
  36         if (ctx->dx_dir_info_count >= ctx->dx_dir_info_size) {
  37                 old_size = ctx->dx_dir_info_size * sizeof(struct dx_dir_info);
  38                 ctx->dx_dir_info_size += 10;
  39                 retval = ext2fs_resize_mem(old_size, ctx->dx_dir_info_size *
  40                                            sizeof(struct dx_dir_info),
  41                                            &ctx->dx_dir_info);
  42                 if (retval) {
  43                         ctx->dx_dir_info_size -= 10;
  44                         return;
  45                 }
  46         }
  47
  48         /*
  49          * Normally, add_dx_dir_info is called with each inode in
  50          * sequential order; but once in a while (like when pass 3
  51          * needs to recreate the root directory or lost+found
  52          * directory) it is called out of order.  In those cases, we
  53          * need to move the dx_dir_info entries down to make room, since
  54          * the dx_dir_info array needs to be sorted by inode number for
  55          * get_dx_dir_info()'s sake.
  56          */
  57         if (ctx->dx_dir_info_count &&
  58             ctx->dx_dir_info[ctx->dx_dir_info_count-1].ino >= ino) {
  59                 for (i = ctx->dx_dir_info_count-1; i > 0; i--)
  60                         if (ctx->dx_dir_info[i-1].ino < ino)
  61                                 break;
  62                 dir = &ctx->dx_dir_info[i];
  63                 if (dir->ino != ino)
  64                         for (j = ctx->dx_dir_info_count++; j > i; j--)
  65                                 ctx->dx_dir_info[j] = ctx->dx_dir_info[j-1];
  66         } else
  67                 dir = &ctx->dx_dir_info[ctx->dx_dir_info_count++];
  68
  69         dir->ino = ino;
  70         dir->numblocks = num_blocks;
  71         dir->hashversion = 0;
  72         dir->dx_block = e2fsck_allocate_memory(ctx, num_blocks
  73                                        * sizeof (struct dx_dirblock_info),
  74                                        "dx_block info array");
  75
  76 }
  77
  78 /*
  79  * get_dx_dir_info() --- given an inode number, try to find the directory
  80  * information entry for it.
  81  */
  82 struct dx_dir_info *e2fsck_get_dx_dir_info(e2fsck_t ctx, ext2_ino_t ino)
  83 {
  84         int     low, high, mid;
  85
  86         low = 0;
  87         high = ctx->dx_dir_info_count-1;
  88         if (!ctx->dx_dir_info)
  89                 return 0;
  90         if (ino == ctx->dx_dir_info[low].ino)
  91                 return &ctx->dx_dir_info[low];
  92         if  (ino == ctx->dx_dir_info[high].ino)
  93                 return &ctx->dx_dir_info[high];
  94
  95         while (low < high) {
  96                 mid = (low+high)/2;
  97                 if (mid == low || mid == high)
  98                         break;
  99                 if (ino == ctx->dx_dir_info[mid].ino)
 100                         return &ctx->dx_dir_info[mid];
 101                 if (ino < ctx->dx_dir_info[mid].ino)
 102                         high = mid;
 103                 else
 104                         low = mid;
 105         }
 106         return 0;
 107 }
 108
 109 /*
 110  * Free the dx_dir_info structure when it isn't needed any more.
 111  */
 112 void e2fsck_free_dx_dir_info(e2fsck_t ctx)
 113 {
 114         int     i;
 115         struct dx_dir_info *dir;
 116
 117         if (ctx->dx_dir_info) {
 118                 dir = ctx->dx_dir_info;
 119                 for (i=0; i < ctx->dx_dir_info_count; i++,dir++) {
 120                         if (dir->dx_block) {
 121                                 ext2fs_free_mem(&dir->dx_block);
 122                                 dir->dx_block = 0;
 123                         }
 124                 }
 125                 ext2fs_free_mem(&ctx->dx_dir_info);
 126                 ctx->dx_dir_info = 0;
 127         }
 128         ctx->dx_dir_info_size = 0;
 129         ctx->dx_dir_info_count = 0;
 130 }
 131
 132 /*
 133  * Return the count of number of directories in the dx_dir_info structure
 134  */
 135 int e2fsck_get_num_dx_dirinfo(e2fsck_t ctx)
 136 {
 137         return ctx->dx_dir_info_count;
 138 }
 139
 140 /*
 141  * A simple interator function
 142  */
 143 struct dx_dir_info *e2fsck_dx_dir_info_iter(e2fsck_t ctx, int *control)
 144 {
 145         if (*control >= ctx->dx_dir_info_count)
 146                 return 0;
 147
 148         return(ctx->dx_dir_info + (*control)++);
 149 }
 150
 151 #endif /* ENABLE_HTREE */