common/environment.c

   1 /*
   2  * Copyright (c) 2007 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
   3  *
   4  * See file CREDITS for list of people who contributed to this
   5  * project.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2
   9  * as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 /**
  22  * @file
  23  * @brief Environment handling support (host and target)
  24  *
  25  * Important: This file will also be used on the host to create
  26  * the default environment when building the U-Boot binary. So
  27  * do not add any new U-Boot related functions here!
  28  */
  29
  30 #ifdef __U_BOOT__
  31 #include <common.h>
  32 #include <command.h>
  33 #include <malloc.h>
  34 #include <errno.h>
  35 #include <fs.h>
  36 #include <fcntl.h>
  37 #include <envfs.h>
  38 #include <xfuncs.h>
  39 #include <libbb.h>
  40 #include <libgen.h>
  41 #include <environment.h>
  42 #else
  43 # define errno_str(x) ("void")
  44 #define EXPORT_SYMBOL(x)
  45 #endif
  46
  47 int file_size_action(const char *filename, struct stat *statbuf,
  48                             void *userdata, int depth)
  49 {
  50         struct action_data *data = userdata;
  51
  52         data->writep += sizeof(struct envfs_inode);
  53         data->writep += PAD4(strlen(filename) + 1 - strlen(data->base));
  54         data->writep += PAD4(statbuf->st_size);
  55         return 1;
  56 }
  57
  58 int file_save_action(const char *filename, struct stat *statbuf,
  59                             void *userdata, int depth)
  60 {
  61         struct action_data *data = userdata;
  62         struct envfs_inode *inode;
  63         int fd;
  64         int namelen = strlen(filename) + 1 - strlen(data->base);
  65
  66         debug("handling file %s size %ld namelen %d\n", filename + strlen(data->base),
  67                 statbuf->st_size, namelen);
  68
  69         inode = (struct envfs_inode*)data->writep;
  70         inode->magic = ENVFS_32(ENVFS_INODE_MAGIC);
  71         inode->namelen = ENVFS_32(namelen);
  72         inode->size = ENVFS_32(statbuf->st_size);
  73         data->writep += sizeof(struct envfs_inode);
  74
  75         strcpy(data->writep, filename + strlen(data->base));
  76         data->writep += PAD4(namelen);
  77
  78         fd = open(filename, O_RDONLY);
  79         if (fd < 0) {
  80                 printf("Open %s %s\n", filename, errno_str());
  81                 goto out;
  82         }
  83
  84         if (read(fd, data->writep, statbuf->st_size) < statbuf->st_size) {
  85                 perror("read");
  86                 goto out;
  87         }
  88         close(fd);
  89
  90         data->writep += PAD4(statbuf->st_size);
  91
  92 out:
  93         return 1;
  94 }
  95
  96 /**
  97  * Make the current environment persistent
  98  * @param[in] filename where to store
  99  * @param[in] dirname what to store (all files in this dir)
 100  * @return 0 on success, anything else in case of failure
 101  *
 102  * Note: This function will also be used on the host! See note in the header
 103  * of this file.
 104  */
 105 int envfs_save(char *filename, char *dirname)
 106 {
 107         struct envfs_super *super;
 108         int envfd, size, ret;
 109         struct action_data data;
 110         void *buf = NULL;
 111
 112         data.writep = 0;
 113         data.base = dirname;
 114
 115         /* first pass: calculate size */
 116         recursive_action(dirname, ACTION_RECURSE, file_size_action,
 117                          NULL, &data, 0);
 118
 119         size = (unsigned long)data.writep;
 120
 121         buf = xzalloc(size + sizeof(struct envfs_super));
 122         data.writep = buf + sizeof(struct envfs_super);
 123
 124         super = (struct envfs_super *)buf;
 125         super->magic = ENVFS_32(ENVFS_MAGIC);
 126         super->size = ENVFS_32(size);
 127
 128         /* second pass: copy files to buffer */
 129         recursive_action(dirname, ACTION_RECURSE, file_save_action,
 130                          NULL, &data, 0);
 131
 132         super->crc = ENVFS_32(crc32(0, buf + sizeof(struct envfs_super), size));
 133         super->sb_crc = ENVFS_32(crc32(0, buf, sizeof(struct envfs_super) - 4));
 134
 135         envfd = open(filename, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
 136         if (envfd < 0) {
 137                 printf("Open %s %s\n", filename, errno_str());
 138                 ret = envfd;
 139                 goto out1;
 140         }
 141
 142         if (write(envfd, buf, size  + sizeof(struct envfs_super)) <
 143                         sizeof(struct envfs_super)) {
 144                 perror("write");
 145                 ret = -1;       /* FIXME */
 146                 goto out;
 147         }
 148
 149         ret = 0;
 150
 151 out:
 152         close(envfd);
 153 out1:
 154         free(buf);
 155         return ret;
 156 }
 157 EXPORT_SYMBOL(envfs_save);
 158
 159 /**
 160  * Restore the last environment into the current one
 161  * @param[in] filename from where to restore
 162  * @param[in] dir where to store the last content
 163  * @return 0 on success, anything else in case of failure
 164  *
 165  * Note: This function will also be used on the host! See note in the header
 166  * of this file.
 167  */
 168 int envfs_load(char *filename, char *dir)
 169 {
 170         struct envfs_super super;
 171         void *buf = NULL, *buf_free = NULL;
 172         int envfd;
 173         int fd, ret = 0;
 174         char *str, *tmp;
 175         int namelen_full;
 176         unsigned long size;
 177
 178         envfd = open(filename, O_RDONLY);
 179         if (envfd < 0) {
 180                 printf("Open %s %s\n", filename, errno_str());
 181                 return -1;
 182         }
 183
 184         /* read superblock */
 185         ret = read(envfd, &super, sizeof(struct envfs_super));
 186         if ( ret < sizeof(struct envfs_super)) {
 187                 perror("read");
 188                 ret = errno;
 189                 goto out;
 190         }
 191
 192         if ( ENVFS_32(super.magic) != ENVFS_MAGIC) {
 193                 printf("envfs: wrong magic on %s\n", filename);
 194                 ret = -EIO;
 195                 goto out;
 196         }
 197
 198         if (crc32(0, (unsigned char *)&super, sizeof(struct envfs_super) - 4)
 199                    != ENVFS_32(super.sb_crc)) {
 200                 printf("wrong crc on env superblock\n");
 201                 goto out;
 202         }
 203
 204         size = ENVFS_32(super.size);
 205         buf = xmalloc(size);
 206         buf_free = buf;
 207         ret = read(envfd, buf, size);
 208         if (ret < size) {
 209                 perror("read");
 210                 goto out;
 211         }
 212
 213         if (crc32(0, (unsigned char *)buf, size)
 214                      != ENVFS_32(super.crc)) {
 215                 printf("wrong crc on env\n");
 216                 goto out;
 217         }
 218
 219         while (size) {
 220                 struct envfs_inode *inode;
 221         uint32_t inode_size,inode_namelen;
 222
 223                 inode = (struct envfs_inode *)buf;
 224
 225                 if (ENVFS_32(inode->magic) != ENVFS_INODE_MAGIC) {
 226                         printf("envfs: wrong magic on %s\n", filename);
 227                         ret = -EIO;
 228                         goto out;
 229                 }
 230                 inode_size = ENVFS_32(inode->size);
 231                 inode_namelen = ENVFS_32(inode->namelen);
 232
 233                 debug("loading %s size %d namelen %d\n", inode->data,
 234                         inode_size, inode_namelen);
 235
 236                 str = concat_path_file(dir, inode->data);
 237                 tmp = strdup(str);
 238                 make_directory(dirname(tmp));
 239                 free(tmp);
 240
 241                 fd = open(str, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 242                 free(str);
 243                 if (fd < 0) {
 244                         printf("Open %s\n", errno_str());
 245                         ret = fd;
 246                         goto out;
 247                 }
 248
 249                 namelen_full = PAD4(inode_namelen);
 250                 ret = write(fd, buf + namelen_full + sizeof(struct envfs_inode),
 251                                 inode_size);
 252                 if (ret < inode_size) {
 253                         perror("write");
 254                         close(fd);
 255                         goto out;
 256                 }
 257                 close(fd);
 258
 259                 buf += PAD4(inode_namelen) + PAD4(inode_size) +
 260                                 sizeof(struct envfs_inode);
 261                 size -= PAD4(inode_namelen) + PAD4(inode_size) +
 262                                 sizeof(struct envfs_inode);
 263         }
 264
 265         ret = 0;
 266 out:
 267         close(envfd);
 268         if (buf_free)
 269                 free(buf_free);
 270         return ret;
 271 }