/* -*- c-file-style: "linux" -*- rsync -- fast file replication program Copyright (C) 1996-2000 by Andrew Tridgell Copyright (C) Paul Mackerras 1996 Copyright (C) 2002 by Martin Pool This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "rsync.h" extern int verbose; extern int dry_run; extern int relative_paths; extern int preserve_links; extern int am_root; extern int preserve_devices; extern int preserve_hard_links; extern int preserve_perms; extern int preserve_uid; extern int preserve_gid; extern int update_only; extern int opt_ignore_existing; extern int csum_length; extern int ignore_times; extern int size_only; extern int io_timeout; extern int protocol_version; extern int always_checksum; extern char *compare_dest; extern int link_dest; extern int whole_file; extern int local_server; extern int read_batch; extern int write_batch; extern int list_only; extern int only_existing; extern int orig_umask; extern int safe_symlinks; extern struct exclude_list_struct server_exclude_list; /* choose whether to skip a particular file */ static int skip_file(char *fname, struct file_struct *file, STRUCT_STAT *st) { if (st->st_size != file->length) { return 0; } if (link_dest) { if (preserve_perms && (st->st_mode & CHMOD_BITS) != (file->mode & CHMOD_BITS)) return 0; if (am_root && preserve_uid && st->st_uid != file->uid) return 0; if (preserve_gid && file->gid != GID_NONE && st->st_gid != file->gid) return 0; } /* if always checksum is set then we use the checksum instead of the file time to determine whether to sync */ if (always_checksum && S_ISREG(st->st_mode)) { char sum[MD4_SUM_LENGTH]; char fnamecmpdest[MAXPATHLEN]; if (compare_dest != NULL) { if (access(fname, 0) != 0) { pathjoin(fnamecmpdest, sizeof fnamecmpdest, compare_dest, fname); fname = fnamecmpdest; } } file_checksum(fname,sum,st->st_size); return memcmp(sum, file->u.sum, protocol_version < 21 ? 2 : MD4_SUM_LENGTH) == 0; } if (size_only) { return 1; } if (ignore_times) { return 0; } return (cmp_modtime(st->st_mtime,file->modtime) == 0); } /* * NULL sum_struct means we have no checksums */ void write_sum_head(int f, struct sum_struct *sum) { static struct sum_struct null_sum; if (sum == NULL) sum = &null_sum; write_int(f, sum->count); write_int(f, sum->blength); if (protocol_version >= 27) write_int(f, sum->s2length); write_int(f, sum->remainder); } /* * set (initialize) the size entries in the per-file sum_struct * calulating dynamic block ans checksum sizes. * * This is only called from generate_and_send_sums() but is a seperate * function to encapsulate the logic. * * The block size is a rounded square root of file length. * * The checksum size is determined according to: * blocksum_bits = BLOCKSUM_EXP + 2*log2(file_len) - log2(block_len) * provided by Donovan Baarda which gives a probability of rsync * algorithm corrupting data and falling back using the whole md4 * checksums. * * This might be made one of several selectable heuristics. */ static void sum_sizes_sqroot(struct sum_struct *sum, uint64 len) { extern unsigned int block_size; unsigned int blength; int s2length; uint32 c; uint64 l; if (block_size) { blength = block_size; } else if (len <= BLOCK_SIZE * BLOCK_SIZE) { blength = BLOCK_SIZE; } else { l = len; c = 1; while (l >>= 2) { c <<= 1; } blength = 0; do { blength |= c; if (len < (uint64)blength * blength) blength &= ~c; c >>= 1; } while (c >= 8); /* round to multiple of 8 */ blength = MAX(blength, BLOCK_SIZE); } if (protocol_version < 27) { s2length = csum_length; } else if (csum_length == SUM_LENGTH) { s2length = SUM_LENGTH; } else { int b = BLOCKSUM_BIAS; l = len; while (l >>= 1) { b += 2; } c = blength; while (c >>= 1 && b) { b--; } s2length = (b + 1 - 32 + 7) / 8; /* add a bit, * subtract rollsum, * round up * --optimize in compiler-- */ s2length = MAX(s2length, csum_length); s2length = MIN(s2length, SUM_LENGTH); } sum->flength = len; sum->blength = blength; sum->s2length = s2length; sum->count = (len + (blength - 1)) / blength; sum->remainder = (len % blength); if (sum->count && verbose > 2) { rprintf(FINFO, "count=%.0f rem=%u blength=%u s2length=%d flength=%.0f\n", (double)sum->count, sum->remainder, sum->blength, sum->s2length, (double)sum->flength); } } /** * Perhaps we want to just send an empty checksum set for this file, * which will force the whole thing to be literally transferred. * * When do we do this? If the user's explicitly said they * want the whole thing, or if { they haven't explicitly * requested a delta, and it's local but not batch mode.} * * Whew. */ static BOOL disable_deltas_p(void) { if (whole_file > 0) return True; if (whole_file == 0 || write_batch || read_batch) return False; return local_server; } /* * Generate and send a stream of signatures/checksums that describe a buffer * * Generate approximately one checksum every block_len bytes. */ static void generate_and_send_sums(struct map_struct *buf, size_t len, int f_out) { size_t i; struct sum_struct sum; OFF_T offset = 0; sum_sizes_sqroot(&sum, len); write_sum_head(f_out, &sum); for (i = 0; i < sum.count; i++) { unsigned int n1 = MIN(len, sum.blength); char *map = map_ptr(buf, offset, n1); uint32 sum1 = get_checksum1(map, n1); char sum2[SUM_LENGTH]; get_checksum2(map, n1, sum2); if (verbose > 3) { rprintf(FINFO, "chunk[%.0f] offset=%.0f len=%u sum1=%08lx\n", (double)i, (double)offset, n1, (unsigned long)sum1); } write_int(f_out, sum1); write_buf(f_out, sum2, sum.s2length); len -= n1; offset += n1; } } /** * Acts on file number @p i from @p flist, whose name is @p fname. * * First fixes up permissions, then generates checksums for the file. * * @note This comment was added later by mbp who was trying to work it * out. It might be wrong. **/ void recv_generator(char *fname, struct file_struct *file, int i, int f_out) { int fd; STRUCT_STAT st; struct map_struct *mapbuf; int statret; char *fnamecmp; char fnamecmpbuf[MAXPATHLEN]; if (list_only) return; if (verbose > 2) rprintf(FINFO,"recv_generator(%s,%d)\n",fname,i); if (server_exclude_list.head && check_exclude(&server_exclude_list, fname, S_ISDIR(file->mode)) < 0) return; statret = link_stat(fname,&st); if (only_existing && statret == -1 && errno == ENOENT) { /* we only want to update existing files */ if (verbose > 1) rprintf(FINFO, "not creating new file \"%s\"\n",fname); return; } if (statret == 0 && !preserve_perms && (S_ISDIR(st.st_mode) == S_ISDIR(file->mode))) { /* if the file exists already and we aren't perserving * permissions then act as though the remote end sent * us the file permissions we already have */ file->mode = (file->mode & ~CHMOD_BITS) | (st.st_mode & CHMOD_BITS); } if (S_ISDIR(file->mode)) { /* The file to be received is a directory, so we need * to prepare appropriately. If there is already a * file of that name and it is *not* a directory, then * we need to delete it. If it doesn't exist, then * recursively create it. */ if (dry_run) return; /* XXXX -- might cause inaccuracies?? -- mbp */ if (statret == 0 && !S_ISDIR(st.st_mode)) { if (robust_unlink(fname) != 0) { rsyserr(FERROR, errno, "recv_generator: unlink %s to make room for directory", full_fname(fname)); return; } statret = -1; } if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) { if (!(relative_paths && errno == ENOENT && create_directory_path(fname, orig_umask) == 0 && do_mkdir(fname, file->mode) == 0)) { rsyserr(FERROR, errno, "recv_generator: mkdir %s failed", full_fname(fname)); } } /* f_out is set to -1 when doing final directory permission and modification time repair */ if (set_perms(fname,file,NULL,0) && verbose && (f_out != -1)) rprintf(FINFO,"%s/\n",fname); return; } if (preserve_links && S_ISLNK(file->mode)) { #if SUPPORT_LINKS char lnk[MAXPATHLEN]; int l; if (safe_symlinks && unsafe_symlink(file->u.link, fname)) { if (verbose) { rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n", full_fname(fname), file->u.link); } return; } if (statret == 0) { l = readlink(fname,lnk,MAXPATHLEN-1); if (l > 0) { lnk[l] = 0; /* A link already pointing to the * right place -- no further action * required. */ if (strcmp(lnk,file->u.link) == 0) { set_perms(fname, file, &st, PERMS_REPORT); return; } } /* Not a symlink, so delete whatever's * already there and put a new symlink * in place. */ delete_file(fname); } if (do_symlink(file->u.link,fname) != 0) { rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed", full_fname(fname), file->u.link); } else { set_perms(fname,file,NULL,0); if (verbose) { rprintf(FINFO,"%s -> %s\n", fname,file->u.link); } } #endif return; } #ifdef HAVE_MKNOD if (am_root && preserve_devices && IS_DEVICE(file->mode)) { if (statret != 0 || st.st_mode != file->mode || st.st_rdev != file->u.rdev) { delete_file(fname); if (verbose > 2) { rprintf(FINFO,"mknod(%s,0%o,0x%x)\n", fname,(int)file->mode,(int)file->u.rdev); } if (do_mknod(fname,file->mode,file->u.rdev) != 0) { rsyserr(FERROR, errno, "mknod %s failed", full_fname(fname)); } else { set_perms(fname,file,NULL,0); if (verbose) rprintf(FINFO,"%s\n",fname); } } else { set_perms(fname, file, &st, PERMS_REPORT); } return; } #endif if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER)) return; if (!S_ISREG(file->mode)) { rprintf(FINFO, "skipping non-regular file \"%s\"\n",fname); return; } fnamecmp = fname; if (statret == -1 && compare_dest != NULL) { /* try the file at compare_dest instead */ int saveerrno = errno; pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname); statret = link_stat(fnamecmpbuf,&st); if (!S_ISREG(st.st_mode)) statret = -1; if (statret == -1) errno = saveerrno; #if HAVE_LINK else if (link_dest && !dry_run) { if (do_link(fnamecmpbuf, fname) != 0) { if (verbose > 0) { rsyserr(FINFO, errno, "link %s => %s", fnamecmpbuf, fname); } } fnamecmp = fnamecmpbuf; } #endif else fnamecmp = fnamecmpbuf; } if (statret == -1) { if (preserve_hard_links && hard_link_check(file, HL_SKIP)) return; if (errno == ENOENT) { write_int(f_out,i); if (!dry_run) write_sum_head(f_out, NULL); } else if (verbose > 1) { rsyserr(FERROR, errno, "recv_generator: failed to open %s", full_fname(fname)); } return; } if (!S_ISREG(st.st_mode)) { if (delete_file(fname) != 0) { return; } /* now pretend the file didn't exist */ if (preserve_hard_links && hard_link_check(file, HL_SKIP)) return; write_int(f_out,i); if (!dry_run) write_sum_head(f_out, NULL); return; } if (opt_ignore_existing && fnamecmp == fname) { if (verbose > 1) rprintf(FINFO,"%s exists\n",fname); return; } if (update_only && cmp_modtime(st.st_mtime,file->modtime)>0 && fnamecmp == fname) { if (verbose > 1) rprintf(FINFO,"%s is newer\n",fname); return; } if (skip_file(fname, file, &st)) { if (fnamecmp == fname) set_perms(fname, file, &st, PERMS_REPORT); return; } if (dry_run) { write_int(f_out,i); return; } if (disable_deltas_p()) { write_int(f_out,i); write_sum_head(f_out, NULL); return; } /* open the file */ fd = do_open(fnamecmp, O_RDONLY, 0); if (fd == -1) { rsyserr(FERROR, errno, "failed to open %s, continuing", full_fname(fnamecmp)); /* pretend the file didn't exist */ if (preserve_hard_links && hard_link_check(file, HL_SKIP)) return; write_int(f_out,i); write_sum_head(f_out, NULL); return; } if (st.st_size > 0) mapbuf = map_file(fd,st.st_size); else mapbuf = NULL; if (verbose > 3) { rprintf(FINFO,"gen mapped %s of size %.0f\n", fnamecmp, (double)st.st_size); } if (verbose > 2) rprintf(FINFO, "generating and sending sums for %d\n", i); write_int(f_out,i); generate_and_send_sums(mapbuf, st.st_size, f_out); close(fd); if (mapbuf) unmap_file(mapbuf); } void generate_files(int f, struct file_list *flist, char *local_name) { int i; int phase=0; char fbuf[MAXPATHLEN]; if (verbose > 2) { rprintf(FINFO, "generator starting pid=%ld count=%d\n", (long)getpid(), flist->count); } if (verbose >= 2) { rprintf(FINFO, disable_deltas_p() ? "delta-transmission disabled for local transfer or --whole-file\n" : "delta transmission enabled\n"); } /* we expect to just sit around now, so don't exit on a timeout. If we really get a timeout then the other process should exit */ io_timeout = 0; for (i = 0; i < flist->count; i++) { struct file_struct *file = flist->files[i]; struct file_struct copy; if (!file->basename) continue; /* we need to ensure that any directories we create have writeable permissions initially so that we can create the files within them. This is then fixed after the files are transferred */ if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) { copy = *file; /* XXX: Could this be causing a problem on SCO? Perhaps their * handling of permissions is strange? */ copy.mode |= S_IWUSR; /* user write */ file = © } recv_generator(local_name ? local_name : f_name_to(file, fbuf), file, i, f); } phase++; csum_length = SUM_LENGTH; ignore_times=1; if (verbose > 2) rprintf(FINFO,"generate_files phase=%d\n",phase); write_int(f,-1); /* files can cycle through the system more than once * to catch initial checksum errors */ while ((i = get_redo_num()) != -1) { struct file_struct *file = flist->files[i]; recv_generator(local_name ? local_name : f_name_to(file, fbuf), file, i, f); } phase++; if (verbose > 2) rprintf(FINFO,"generate_files phase=%d\n",phase); write_int(f,-1); if (preserve_hard_links) do_hard_links(); /* now we need to fix any directory permissions that were * modified during the transfer */ for (i = 0; i < flist->count; i++) { struct file_struct *file = flist->files[i]; if (!file->basename || !S_ISDIR(file->mode)) continue; recv_generator(local_name ? local_name : f_name(file), file, i, -1); } if (verbose > 2) rprintf(FINFO,"generate_files finished\n"); }