write-devices.diff

   1 This patch adds the --write-devices option, which will try to write
   2 data into a device when used as a destination.
   3
   4 To use this patch, run these commands for a successful build:
   5
   6     patch -p1 <patches/write-devices.diff
   7     ./configure                      (optional if already run)
   8     make
   9
  10 This patch has not yet been tested by me (Wayne), but was provided
  11 Darryl Dixon.  Thanks!
  12
  13 based-on: d73762eea3f15f2c56bb3fa9394ad1883c25c949
  14 diff --git a/generator.c b/generator.c
  15 --- a/generator.c
  16 +++ b/generator.c
  17 @@ -39,6 +39,7 @@ extern int preserve_acls;
  18  extern int preserve_xattrs;
  19  extern int preserve_links;
  20  extern int preserve_devices;
  21 +extern int write_devices;
  22  extern int preserve_specials;
  23  extern int preserve_hard_links;
  24  extern int preserve_executability;
  25 @@ -1693,7 +1694,7 @@ static void recv_generator(char *fname, struct file_struct *file, int ndx,
  26
  27         fnamecmp_type = FNAMECMP_FNAME;
  28
  29 -       if (statret == 0 && !S_ISREG(sx.st.st_mode)) {
  30 +       if (statret == 0 && !(S_ISREG(sx.st.st_mode) || (write_devices && IS_DEVICE(sx.st.st_mode)))) {
  31                 if (delete_item(fname, sx.st.st_mode, del_opts | DEL_FOR_FILE) != 0)
  32                         goto cleanup;
  33                 statret = -1;
  34 diff --git a/options.c b/options.c
  35 --- a/options.c
  36 +++ b/options.c
  37 @@ -50,6 +50,7 @@ int append_mode = 0;
  38  int keep_dirlinks = 0;
  39  int copy_dirlinks = 0;
  40  int copy_links = 0;
  41 +int write_devices = 0;
  42  int preserve_links = 0;
  43  int preserve_hard_links = 0;
  44  int preserve_acls = 0;
  45 @@ -705,6 +706,7 @@ void usage(enum logcode F)
  46    rprintf(F," -o, --owner                 preserve owner (super-user only)\n");
  47    rprintf(F," -g, --group                 preserve group\n");
  48    rprintf(F,"     --devices               preserve device files (super-user only)\n");
  49 +  rprintf(F," -w  --write-devices         write to devices as regular files (implies --inplace)\n");
  50    rprintf(F,"     --specials              preserve special files\n");
  51    rprintf(F," -D                          same as --devices --specials\n");
  52    rprintf(F," -t, --times                 preserve modification times\n");
  53 @@ -887,6 +889,7 @@ static struct poptOption long_options[] = {
  54    {"no-D",             0,  POPT_ARG_NONE,   0, OPT_NO_D, 0, 0 },
  55    {"devices",          0,  POPT_ARG_VAL,    &preserve_devices, 1, 0, 0 },
  56    {"no-devices",       0,  POPT_ARG_VAL,    &preserve_devices, 0, 0, 0 },
  57 +  {"write-devices",   'w', POPT_ARG_NONE,   0, 'w', 0, 0 },
  58    {"specials",         0,  POPT_ARG_VAL,    &preserve_specials, 1, 0, 0 },
  59    {"no-specials",      0,  POPT_ARG_VAL,    &preserve_specials, 0, 0, 0 },
  60    {"links",           'l', POPT_ARG_VAL,    &preserve_links, 1, 0, 0 },
  61 @@ -1808,6 +1811,11 @@ int parse_arguments(int *argc_p, const char ***argv_p)
  62                         return 0;
  63  #endif
  64
  65 +               case 'w':
  66 +                       write_devices = 1;
  67 +                       inplace = 1;
  68 +                       break;
  69 +
  70                 default:
  71                         /* A large opt value means that set_refuse_options()
  72                          * turned this option off. */
  73 @@ -2792,6 +2800,9 @@ void server_options(char **args, int *argc_p)
  74         if (relative_paths && !implied_dirs && (!am_sender || protocol_version >= 30))
  75                 args[ac++] = "--no-implied-dirs";
  76
  77 +       if (write_devices)
  78 +               args[ac++] = "--write-devices";
  79 +
  80         if (remove_source_files == 1)
  81                 args[ac++] = "--remove-source-files";
  82         else if (remove_source_files)
  83 diff --git a/receiver.c b/receiver.c
  84 --- a/receiver.c
  85 +++ b/receiver.c
  86 @@ -39,6 +39,7 @@ extern int protocol_version;
  87  extern int relative_paths;
  88  extern int preserve_hard_links;
  89  extern int preserve_perms;
  90 +extern int write_devices;
  91  extern int preserve_xattrs;
  92  extern int basis_dir_cnt;
  93  extern int make_backups;
  94 @@ -231,7 +232,7 @@ int open_tmpfile(char *fnametmp, const char *fname, struct file_struct *file)
  95  }
  96
  97  static int receive_data(int f_in, char *fname_r, int fd_r, OFF_T size_r,
  98 -                       const char *fname, int fd, OFF_T total_size)
  99 +                       const char *fname, int fd, struct file_struct *file)
 100  {
 101         static char file_sum1[MAX_DIGEST_LEN];
 102         struct map_struct *mapbuf;
 103 @@ -245,10 +246,10 @@ static int receive_data(int f_in, char *fname_r, int fd_r, OFF_T size_r,
 104         char *map = NULL;
 105
 106  #ifdef SUPPORT_PREALLOCATION
 107 -       if (preallocate_files && fd != -1 && total_size > 0 && (!inplace || total_size > size_r)) {
 108 +       if (preallocate_files && fd != -1 && F_LENGTH(file) > 0 && (!inplace || F_LENGTH(file) > size_r)) {
 109                 /* Try to preallocate enough space for file's eventual length.  Can
 110                  * reduce fragmentation on filesystems like ext4, xfs, and NTFS. */
 111 -               if ((preallocated_len = do_fallocate(fd, 0, total_size)) < 0)
 112 +               if ((preallocated_len = do_fallocate(fd, 0, F_LENGTH(file))) < 0)
 113                         rsyserr(FWARNING, errno, "do_fallocate %s", full_fname(fname));
 114         } else
 115  #endif
 116 @@ -285,7 +286,7 @@ static int receive_data(int f_in, char *fname_r, int fd_r, OFF_T size_r,
 117                 if (append_mode == 2 && mapbuf) {
 118                         for (j = CHUNK_SIZE; j < sum.flength; j += CHUNK_SIZE) {
 119                                 if (INFO_GTE(PROGRESS, 1))
 120 -                                       show_progress(offset, total_size);
 121 +                                       show_progress(offset, F_LENGTH(file));
 122                                 sum_update(map_ptr(mapbuf, offset, CHUNK_SIZE),
 123                                            CHUNK_SIZE);
 124                                 offset = j;
 125 @@ -293,7 +294,7 @@ static int receive_data(int f_in, char *fname_r, int fd_r, OFF_T size_r,
 126                         if (offset < sum.flength) {
 127                                 int32 len = (int32)(sum.flength - offset);
 128                                 if (INFO_GTE(PROGRESS, 1))
 129 -                                       show_progress(offset, total_size);
 130 +                                       show_progress(offset, F_LENGTH(file));
 131                                 sum_update(map_ptr(mapbuf, offset, len), len);
 132                         }
 133                 }
 134 @@ -307,7 +308,7 @@ static int receive_data(int f_in, char *fname_r, int fd_r, OFF_T size_r,
 135
 136         while ((i = recv_token(f_in, &data)) != 0) {
 137                 if (INFO_GTE(PROGRESS, 1))
 138 -                       show_progress(offset, total_size);
 139 +                       show_progress(offset, F_LENGTH(file));
 140
 141                 if (allowed_lull)
 142                         maybe_send_keepalive(time(NULL), MSK_ALLOW_FLUSH | MSK_ACTIVE_RECEIVER);
 143 @@ -377,16 +378,16 @@ static int receive_data(int f_in, char *fname_r, int fd_r, OFF_T size_r,
 144
 145  #ifdef HAVE_FTRUNCATE
 146         /* inplace: New data could be shorter than old data.
 147 -        * preallocate_files: total_size could have been an overestimate.
 148 +        * preallocate_files: F_LENGTH(file) could have been an overestimate.
 149          *     Cut off any extra preallocated zeros from dest file. */
 150 -       if ((inplace || preallocated_len > offset) && fd != -1 && do_ftruncate(fd, offset) < 0) {
 151 +       if ((inplace || preallocated_len > offset) && fd != -1 && !IS_DEVICE(file->mode) && do_ftruncate(fd, offset) < 0) {
 152                 rsyserr(FERROR_XFER, errno, "ftruncate failed on %s",
 153                         full_fname(fname));
 154         }
 155  #endif
 156
 157         if (INFO_GTE(PROGRESS, 1))
 158 -               end_progress(total_size);
 159 +               end_progress(F_LENGTH(file));
 160
 161         sum_len = sum_end(file_sum1);
 162
 163 @@ -402,9 +403,9 @@ static int receive_data(int f_in, char *fname_r, int fd_r, OFF_T size_r,
 164  }
 165
 166
 167 -static void discard_receive_data(int f_in, OFF_T length)
 168 +static void discard_receive_data(int f_in, struct file_struct *file)
 169  {
 170 -       receive_data(f_in, NULL, -1, 0, NULL, -1, length);
 171 +       receive_data(f_in, NULL, -1, 0, NULL, -1, file);
 172  }
 173
 174  static void handle_delayed_updates(char *local_name)
 175 @@ -660,7 +661,7 @@ int recv_files(int f_in, int f_out, char *local_name)
 176                                         "(Skipping batched update for%s \"%s\")\n",
 177                                         redoing ? " resend of" : "",
 178                                         fname);
 179 -                               discard_receive_data(f_in, F_LENGTH(file));
 180 +                               discard_receive_data(f_in, file);
 181                                 file->flags |= FLAG_FILE_SENT;
 182                                 continue;
 183                         }
 184 @@ -671,13 +672,13 @@ int recv_files(int f_in, int f_out, char *local_name)
 185                 if (!do_xfers) { /* log the transfer */
 186                         log_item(FCLIENT, file, iflags, NULL);
 187                         if (read_batch)
 188 -                               discard_receive_data(f_in, F_LENGTH(file));
 189 +                               discard_receive_data(f_in, file);
 190                         continue;
 191                 }
 192                 if (write_batch < 0) {
 193                         log_item(FCLIENT, file, iflags, NULL);
 194                         if (!am_server)
 195 -                               discard_receive_data(f_in, F_LENGTH(file));
 196 +                               discard_receive_data(f_in, file);
 197                         if (inc_recurse)
 198                                 send_msg_int(MSG_SUCCESS, ndx);
 199                         continue;
 200 @@ -767,7 +768,7 @@ int recv_files(int f_in, int f_out, char *local_name)
 201                 } else if (do_fstat(fd1,&st) != 0) {
 202                         rsyserr(FERROR_XFER, errno, "fstat %s failed",
 203                                 full_fname(fnamecmp));
 204 -                       discard_receive_data(f_in, F_LENGTH(file));
 205 +                       discard_receive_data(f_in, file);
 206                         close(fd1);
 207                         if (inc_recurse)
 208                                 send_msg_int(MSG_NO_SEND, ndx);
 209 @@ -782,18 +783,32 @@ int recv_files(int f_in, int f_out, char *local_name)
 210                          */
 211                         rprintf(FERROR_XFER, "recv_files: %s is a directory\n",
 212                                 full_fname(fnamecmp));
 213 -                       discard_receive_data(f_in, F_LENGTH(file));
 214 +                       discard_receive_data(f_in, file);
 215                         close(fd1);
 216                         if (inc_recurse)
 217                                 send_msg_int(MSG_NO_SEND, ndx);
 218                         continue;
 219                 }
 220
 221 -               if (fd1 != -1 && !S_ISREG(st.st_mode)) {
 222 +               if (fd1 != -1 && !(S_ISREG(st.st_mode) || (write_devices && IS_DEVICE(st.st_mode)))) {
 223                         close(fd1);
 224                         fd1 = -1;
 225                 }
 226
 227 +               /* On Linux systems (at least), st_size is typically 0 for devices.
 228 +                * If so, try to determine the actual device size. */
 229 +               if (fd1 != -1 && IS_DEVICE(st.st_mode) && st.st_size == 0) {
 230 +                       OFF_T off = lseek(fd1, 0, SEEK_END);
 231 +                       if (off == (OFF_T) -1)
 232 +                               rsyserr(FERROR, errno, "failed to seek to end of %s to determine size", fname);
 233 +                       else {
 234 +                               st.st_size = off;
 235 +                               off = lseek(fd1, 0, SEEK_SET);
 236 +                               if (off != 0)
 237 +                                       rsyserr(FERROR, errno, "failed to seek back to beginning of %s to read it", fname);
 238 +                       }
 239 +               }
 240 +
 241                 /* If we're not preserving permissions, change the file-list's
 242                  * mode based on the local permissions and some heuristics. */
 243                 if (!preserve_perms) {
 244 @@ -825,7 +840,7 @@ int recv_files(int f_in, int f_out, char *local_name)
 245                 }
 246
 247                 if (fd2 == -1) {
 248 -                       discard_receive_data(f_in, F_LENGTH(file));
 249 +                       discard_receive_data(f_in, file);
 250                         if (fd1 != -1)
 251                                 close(fd1);
 252                         if (inc_recurse)
 253 @@ -840,8 +855,7 @@ int recv_files(int f_in, int f_out, char *local_name)
 254                         rprintf(FINFO, "%s\n", fname);
 255
 256                 /* recv file data */
 257 -               recv_ok = receive_data(f_in, fnamecmp, fd1, st.st_size,
 258 -                                      fname, fd2, F_LENGTH(file));
 259 +               recv_ok = receive_data(f_in, fnamecmp, fd1, st.st_size, fname, fd2, file);
 260
 261                 log_item(log_code, file, iflags, NULL);
 262