From: Michael Vrable Date: Tue, 17 Jul 2007 20:51:29 +0000 (-0700) Subject: Implement a more complex inclusion/exclusion system for files. X-Git-Url: http://git.vrable.net/?p=cumulus.git;a=commitdiff_plain;h=e09f2cc5f499a8d475d723e8c038dd086a551457 Implement a more complex inclusion/exclusion system for files. Allow multiple paths to be specified for backups, to allow different parts of the filesystem tree to be selected for backup in a single snapshot. --- diff --git a/scandir.cc b/scandir.cc index 10972cd..980d843 100644 --- a/scandir.cc +++ b/scandir.cc @@ -59,10 +59,16 @@ std::ostringstream metadata; /* Keep track of all segments which are needed to reconstruct the snapshot. */ std::set segment_list; -void scandir(const string& path); +void scandir(const string& path, bool include); /* Selection of files to include/exclude in the snapshot. */ -std::list excludes; +std::list includes; // Paths in which files should be saved +std::list excludes; // Paths which will not be saved +std::list searches; // Directories we don't want to save, but + // do want to descend searching for data + // in included paths + +bool relative_paths = true; /* Ensure contents of metadata are flushed to an object. */ void metadata_flush() @@ -252,7 +258,7 @@ int64_t dumpfile(int fd, dictionary &file_info, const string &path) return size; } -void scanfile(const string& path) +void scanfile(const string& path, bool include) { int fd; long flags; @@ -262,22 +268,51 @@ void scanfile(const string& path) int64_t file_size; list refs; + string true_path; + if (relative_paths) + true_path = path; + else + true_path = "/" + path; + // Set to true if the item is a directory and we should recursively scan bool recurse = false; + // Set to true if we should scan through the contents of this directory, + // but not actually back files up + bool scan_only = false; + // Check this file against the include/exclude list to see if it should be // considered + for (list::iterator i = includes.begin(); + i != includes.end(); ++i) { + if (path == *i) { + printf("Including %s\n", path.c_str()); + include = true; + } + } + for (list::iterator i = excludes.begin(); i != excludes.end(); ++i) { if (path == *i) { printf("Excluding %s\n", path.c_str()); - return; + include = false; + } + } + + for (list::iterator i = searches.begin(); + i != searches.end(); ++i) { + if (path == *i) { + printf("Scanning %s\n", path.c_str()); + scan_only = true; } } + if (!include && !scan_only) + return; + dictionary file_info; - lstat(path.c_str(), &stat_buf); + lstat(true_path.c_str(), &stat_buf); printf("%s\n", path.c_str()); @@ -318,7 +353,7 @@ void scanfile(const string& path) * the symlink. Allocate slightly more space, so that we ask for more * bytes than we expect and so check for truncation. */ buf = new char[stat_buf.st_size + 2]; - len = readlink(path.c_str(), buf, stat_buf.st_size + 1); + len = readlink(true_path.c_str(), buf, stat_buf.st_size + 1); if (len < 0) { fprintf(stderr, "error reading symlink: %m\n"); } else if (len <= stat_buf.st_size) { @@ -345,9 +380,9 @@ void scanfile(const string& path) * We also add in O_NOATIME, since this may reduce disk writes (for * inode updates). However, O_NOATIME may result in EPERM, so if the * initial open fails, try again without O_NOATIME. */ - fd = open(path.c_str(), O_RDONLY|O_NOATIME|O_NOFOLLOW|O_NONBLOCK); + fd = open(true_path.c_str(), O_RDONLY|O_NOATIME|O_NOFOLLOW|O_NONBLOCK); if (fd < 0) { - fd = open(path.c_str(), O_RDONLY|O_NOFOLLOW|O_NONBLOCK); + fd = open(true_path.c_str(), O_RDONLY|O_NOFOLLOW|O_NONBLOCK); } if (fd < 0) { fprintf(stderr, "Unable to open file %s: %m\n", path.c_str()); @@ -395,12 +430,18 @@ void scanfile(const string& path) // If we hit a directory, now that we've written the directory itself, // recursively scan the directory. if (recurse) - scandir(path); + scandir(path, include); } -void scandir(const string& path) +void scandir(const string& path, bool include) { - DIR *dir = opendir(path.c_str()); + string true_path; + if (relative_paths) + true_path = path; + else + true_path = "/" + path; + + DIR *dir = opendir(true_path.c_str()); if (dir == NULL) { fprintf(stderr, "Error: %m\n"); @@ -422,30 +463,80 @@ void scandir(const string& path) i != contents.end(); ++i) { const string& filename = *i; if (path == ".") - scanfile(filename); + scanfile(filename, include); else - scanfile(path + "/" + filename); + scanfile(path + "/" + filename, include); } closedir(dir); } +/* Include the specified file path in the backups. Append the path to the + * includes list, and to ensure that we actually see the path when scanning the + * directory tree, add all the parent directories to the search list, which + * means we will scan through the directory listing even if the files + * themselves are excluded from being backed up. */ +void add_include(const char *path) +{ + printf("Add: %s\n", path); + /* Was an absolute path specified? If so, we'll need to start scanning + * from the root directory. Make sure that the user was consistent in + * providing either all relative paths or all absolute paths. */ + if (path[0] == '/') { + if (includes.size() > 0 && relative_paths == true) { + fprintf(stderr, + "Error: Cannot mix relative and absolute paths!\n"); + exit(1); + } + + relative_paths = false; + + // Skip over leading '/' + path++; + } else if (relative_paths == false && path[0] != '/') { + fprintf(stderr, "Error: Cannot mix relative and absolute paths!\n"); + exit(1); + } + + includes.push_back(path); + + /* Split the specified path into directory components, and ensure that we + * descend into all the directories along the path. */ + const char *slash = path; + + if (path[0] == '\0') + return; + + while ((slash = strchr(slash + 1, '/')) != NULL) { + string component(path, slash - path); + searches.push_back(component); + } +} + void usage(const char *program) { - fprintf(stderr, - "Usage: %s [OPTION]... SOURCE DEST\n" - "Produce backup snapshot of files in SOURCE and store to DEST.\n" - "\n" - "Options:\n" - " --exclude=PATH exclude files in PATH from snapshot\n" - " --localdb=PATH local backup metadata is stored in PATH\n", - program); + fprintf( + stderr, + "Usage: %s [OPTION]... --dest=DEST PATHS...\n" + "Produce backup snapshot of files in SOURCE and store to DEST.\n" + "\n" + "Options:\n" + " --dest=PATH path where backup is to be written [REQUIRED]\n" + " --exclude=PATH exclude files in PATH from snapshot\n" + " --localdb=PATH local backup metadata is stored in PATH\n" + " --filter=COMMAND program through which to filter segment data\n" + " (defaults to \"bzip2 -c\")\n" + " --filter-extension=EXT\n" + " string to append to segment files\n" + " (defaults to \".bz2\")\n", + program + ); } int main(int argc, char *argv[]) { string backup_source = "."; - string backup_dest = "."; + string backup_dest = ""; string localdb_dir = ""; while (1) { @@ -454,6 +545,7 @@ int main(int argc, char *argv[]) {"exclude", 1, 0, 0}, // 1 {"filter", 1, 0, 0}, // 2 {"filter-extension", 1, 0, 0}, // 3 + {"dest", 1, 0, 0}, // 4 {NULL, 0, 0, 0}, }; @@ -469,7 +561,10 @@ int main(int argc, char *argv[]) localdb_dir = optarg; break; case 1: // --exclude - excludes.push_back(optarg); + if (optarg[0] != '/') + excludes.push_back(optarg); + else + excludes.push_back(optarg + 1); break; case 2: // --filter filter_program = optarg; @@ -477,6 +572,9 @@ int main(int argc, char *argv[]) case 3: // --filter-extension filter_extension = optarg; break; + case 4: // --dest + backup_dest = optarg; + break; default: fprintf(stderr, "Unhandled long option!\n"); return 1; @@ -492,15 +590,47 @@ int main(int argc, char *argv[]) return 1; } + searches.push_back("."); + if (optind == argc) { + add_include("."); + } else { + for (int i = optind; i < argc; i++) + add_include(argv[i]); + } + backup_source = argv[optind]; - backup_dest = argv[argc - 1]; + if (backup_dest == "") { + fprintf(stderr, + "Error: Backup destination must be specified with --dest=\n"); + usage(argv[0]); + return 1; + } + + // Default for --localdb is the same as --dest if (localdb_dir == "") { localdb_dir = backup_dest; } - printf("Source: %s\nDest: %s\nDatabase: %s\n\n", - backup_source.c_str(), backup_dest.c_str(), localdb_dir.c_str()); + // Dump paths for debugging/informational purposes + { + list::const_iterator i; + + printf("--dest=%s\n--localdb=%s\n\n", + backup_dest.c_str(), localdb_dir.c_str()); + + printf("Includes:\n"); + for (i = includes.begin(); i != includes.end(); ++i) + printf(" %s\n", i->c_str()); + + printf("Excludes:\n"); + for (i = excludes.begin(); i != excludes.end(); ++i) + printf(" %s\n", i->c_str()); + + printf("Searching:\n"); + for (i = searches.begin(); i != searches.end(); ++i) + printf(" %s\n", i->c_str()); + } tss = new TarSegmentStore(backup_dest); block_buf = new char[LBS_BLOCK_SIZE]; @@ -525,11 +655,7 @@ int main(int argc, char *argv[]) statcache = new StatCache; statcache->Open(localdb_dir.c_str(), desc_buf); - try { - scanfile("."); - } catch (IOException e) { - fprintf(stderr, "IOException: %s\n", e.getError().c_str()); - } + scanfile(".", false); metadata_flush(); const string md = metadata_root.str();