xattrs.diff

   1 This patch adds backward-compatibility support for the --xattrs option.
   2 Since the main release has never had xattr support, the trunk doesn't
   3 need this code.  If you want to make rsync 3.0.x communicate with an
   4 older (patched) release, use this.
   5
   6 To use this patch, run these commands for a successful build:
   7
   8     patch -p1 <patches/acls.diff
   9     patch -p1 <patches/xattrs.diff
  10     ./configure                         (optional if already run)
  11     make
  12
  13 --- old/compat.c
  14 +++ new/compat.c
  15 @@ -147,13 +147,6 @@ void setup_protocol(int f_out,int f_in)
  16                             protocol_version);
  17                         exit_cleanup(RERR_PROTOCOL);
  18                 }
  19 -               if (preserve_xattrs && !local_server) {
  20 -                       rprintf(FERROR,
  21 -                           "--xattrs requires protocol 30 or higher"
  22 -                           " (negotiated %d).\n",
  23 -                           protocol_version);
  24 -                       exit_cleanup(RERR_PROTOCOL);
  25 -               }
  26         }
  27
  28         if (delete_mode && !(delete_before+delete_during+delete_after)) {
  29 --- old/xattrs.c
  30 +++ new/xattrs.c
  31 @@ -20,6 +20,7 @@
  32   */
  33
  34  #include "rsync.h"
  35 +#include "io.h"
  36  #include "lib/sysxattrs.h"
  37
  38  #ifdef SUPPORT_XATTRS
  39 @@ -31,6 +32,7 @@ extern int am_generator;
  40  extern int read_only;
  41  extern int list_only;
  42  extern int checksum_seed;
  43 +extern int protocol_version;
  44
  45  #define RSYNC_XAL_INITIAL 5
  46  #define RSYNC_XAL_LIST_INITIAL 100
  47 @@ -231,7 +233,7 @@ static int rsync_xal_get(const char *fna
  48                 if (!(ptr = get_xattr_data(fname, name, &datum_len, 0)))
  49                         return -1;
  50
  51 -               if (datum_len > MAX_FULL_DATUM) {
  52 +               if (datum_len > MAX_FULL_DATUM && protocol_version >= 30) {
  53                         /* For large datums, we store a flag and a checksum. */
  54                         name_offset = 1 + MAX_DIGEST_LEN;
  55                         sum_init(checksum_seed);
  56 @@ -295,7 +297,7 @@ static int find_matching_xattr(item_list
  57                          || rxas1[j].datum_len != rxas2[j].datum_len
  58                          || strcmp(rxas1[j].name, rxas2[j].name))
  59                                 break;
  60 -                       if (rxas1[j].datum_len > MAX_FULL_DATUM) {
  61 +                       if (rxas1[j].datum_len > MAX_FULL_DATUM && protocol_version >= 30) {
  62                                 if (memcmp(rxas1[j].datum + 1,
  63                                            rxas2[j].datum + 1,
  64                                            MAX_DIGEST_LEN) != 0)
  65 @@ -332,34 +334,43 @@ int send_xattr(statx *sxp, int f)
  66  {
  67         int ndx = find_matching_xattr(sxp->xattr);
  68
  69 -       /* Send 0 (-1 + 1) to indicate that literal xattr data follows. */
  70 -       write_varint(f, ndx + 1);
  71 +       if (protocol_version < 30) {
  72 +               if (ndx < 0)
  73 +                       write_byte(f, 'X');
  74 +               else {
  75 +                       write_byte(f, 'x');
  76 +                       write_int(f, ndx);
  77 +               }
  78 +       } else {
  79 +               /* Send 0 (-1 + 1) to indicate that literal xattr data follows. */
  80 +               write_varint(f, ndx + 1);
  81 +       }
  82
  83         if (ndx < 0) {
  84                 rsync_xa *rxa;
  85                 int count = sxp->xattr->count;
  86 -               write_varint(f, count);
  87 +               write_varint30(f, count);
  88                 for (rxa = sxp->xattr->items; count--; rxa++) {
  89  #ifdef HAVE_LINUX_XATTRS
  90 -                       write_varint(f, rxa->name_len);
  91 -                       write_varint(f, rxa->datum_len);
  92 +                       write_varint30(f, rxa->name_len);
  93 +                       write_varint30(f, rxa->datum_len);
  94                         write_buf(f, rxa->name, rxa->name_len);
  95  #else
  96                         /* We strip the rsync prefix from disguised namespaces
  97                          * and put everything else in the user namespace. */
  98                         if (HAS_PREFIX(rxa->name, RSYNC_PREFIX)
  99                          && rxa->name[RPRE_LEN] != '%') {
 100 -                               write_varint(f, rxa->name_len - RPRE_LEN);
 101 -                               write_varint(f, rxa->datum_len);
 102 +                               write_varint30(f, rxa->name_len - RPRE_LEN);
 103 +                               write_varint30(f, rxa->datum_len);
 104                                 write_buf(f, rxa->name + RPRE_LEN, rxa->name_len - RPRE_LEN);
 105                         } else {
 106 -                               write_varint(f, rxa->name_len + UPRE_LEN);
 107 -                               write_varint(f, rxa->datum_len);
 108 +                               write_varint30(f, rxa->name_len + UPRE_LEN);
 109 +                               write_varint30(f, rxa->datum_len);
 110                                 write_buf(f, USER_PREFIX, UPRE_LEN);
 111                                 write_buf(f, rxa->name, rxa->name_len);
 112                         }
 113  #endif
 114 -                       if (rxa->datum_len > MAX_FULL_DATUM)
 115 +                       if (rxa->datum_len > MAX_FULL_DATUM && protocol_version >= 30)
 116                                 write_buf(f, rxa->datum + 1, MAX_DIGEST_LEN);
 117                         else
 118                                 write_buf(f, rxa->datum, rxa->datum_len);
 119 @@ -409,7 +420,7 @@ int xattr_diff(struct file_struct *file,
 120                 cmp = rec_cnt ? strcmp(snd_rxa->name, rec_rxa->name) : -1;
 121                 if (cmp > 0)
 122                         same = 0;
 123 -               else if (snd_rxa->datum_len > MAX_FULL_DATUM) {
 124 +               else if (snd_rxa->datum_len > MAX_FULL_DATUM && protocol_version >= 30) {
 125                         same = cmp == 0 && snd_rxa->datum_len == rec_rxa->datum_len
 126                             && memcmp(snd_rxa->datum + 1, rec_rxa->datum + 1,
 127                                       MAX_DIGEST_LEN) == 0;
 128 @@ -452,6 +463,9 @@ void send_xattr_request(const char *fnam
 129         int j, cnt, prior_req = -1;
 130         rsync_xa *rxa;
 131
 132 +       if (protocol_version < 30)
 133 +               return;
 134 +
 135         lst += F_XATTR(file);
 136         cnt = lst->count;
 137         for (rxa = lst->items, j = 0; j < cnt; rxa++, j++) {
 138 @@ -523,6 +537,9 @@ void recv_xattr_request(struct file_stru
 139         rsync_xa *rxa;
 140         int rel_pos, cnt;
 141
 142 +       if (protocol_version < 30)
 143 +               return;
 144 +
 145         if (F_XATTR(file) < 0) {
 146                 rprintf(FERROR, "recv_xattr_request: internal data error!\n");
 147                 exit_cleanup(RERR_STREAMIO);
 148 @@ -569,7 +586,22 @@ void receive_xattr(struct file_struct *f
 149  {
 150         static item_list temp_xattr = EMPTY_ITEM_LIST;
 151         int count;
 152 -       int ndx = read_varint(f);
 153 +       int ndx;
 154 +
 155 +       if (protocol_version >= 30)
 156 +               ndx = read_varint(f);
 157 +       else {
 158 +               int tag = read_byte(f);
 159 +               if (tag == 'x')
 160 +                       ndx = read_int(f) + 1;
 161 +               else if (tag == 'X')
 162 +                       ndx = 0;
 163 +               else {
 164 +                       rprintf(FERROR, "receive_xattr: unknown extended attribute"
 165 +                               " type tag (%02x) for %s\n", tag, f_name(file, NULL));
 166 +                       exit_cleanup(RERR_STREAMIO);
 167 +               }
 168 +       }
 169
 170         if (ndx < 0 || (size_t)ndx > rsync_xal_l.count) {
 171                 rprintf(FERROR, "receive_xattr: xa index %d out of"
 172 @@ -582,7 +614,7 @@ void receive_xattr(struct file_struct *f
 173                 return;
 174         }
 175
 176 -       if ((count = read_varint(f)) != 0) {
 177 +       if ((count = read_varint30(f)) != 0) {
 178                 (void)EXPAND_ITEM_LIST(&temp_xattr, rsync_xa, count);
 179                 temp_xattr.count = 0;
 180         }
 181 @@ -590,9 +622,10 @@ void receive_xattr(struct file_struct *f
 182         while (count--) {
 183                 char *ptr, *name;
 184                 rsync_xa *rxa;
 185 -               size_t name_len = read_varint(f);
 186 -               size_t datum_len = read_varint(f);
 187 -               size_t dget_len = datum_len > MAX_FULL_DATUM ? 1 + MAX_DIGEST_LEN : datum_len;
 188 +               size_t name_len = read_varint30(f);
 189 +               size_t datum_len = read_varint30(f);
 190 +               size_t dget_len = datum_len > MAX_FULL_DATUM && protocol_version >= 30
 191 +                               ? 1 + MAX_DIGEST_LEN : datum_len;
 192                 size_t extra_len = MIGHT_NEED_RPRE ? RPRE_LEN : 0;
 193                 if (dget_len + extra_len < dget_len)
 194                         out_of_memory("receive_xattr"); /* overflow */