diff options
Diffstat (limited to 'backup/backup.cpp')
| -rw-r--r-- | backup/backup.cpp | 674 |
1 files changed, 674 insertions, 0 deletions
diff --git a/backup/backup.cpp b/backup/backup.cpp new file mode 100644 index 00000000..48f64eec --- /dev/null +++ b/backup/backup.cpp @@ -0,0 +1,674 @@ +// Copyright 2009 The Android Open Source Project + +#include <stdio.h> +#include <stdlib.h> +#include <stdarg.h> +#include <string.h> +#include <unistd.h> +#include <fcntl.h> +#include <time.h> +#include <dirent.h> +#include <errno.h> +#include <assert.h> +#include <ctype.h> +#include <utime.h> +#include <sys/stat.h> +#include <sys/types.h> + +#include <cutils/properties.h> + +#include <private/android_filesystem_config.h> + +#ifndef PATH_MAX +#define PATH_MAX 4096 +#endif + +#define FILE_VERSION 0xffff0001 + +namespace android { + +static char nameBuffer[PATH_MAX]; +static struct stat statBuffer; + +static char copyBuffer[8192]; + +#define SPECIAL_NO_TOUCH 0 +#define SPECIAL_NO_BACKUP 1 + +struct special_dir { + const char* path; + int type; +}; + +/* Directory paths that we will not backup/restore */ +static const struct special_dir SKIP_PATHS[] = { + { "/data/misc", SPECIAL_NO_TOUCH }, + { "/data/system/batterystats.bin", SPECIAL_NO_TOUCH }, + { "/data/system/location", SPECIAL_NO_TOUCH }, + { "/data/dalvik-cache", SPECIAL_NO_BACKUP }, + { NULL, 0 }, +}; + +/* This is just copied from the shell's built-in wipe command. */ +static int wipe (const char *path) +{ + DIR *dir; + struct dirent *de; + int ret; + int i; + + dir = opendir(path); + + if (dir == NULL) { + fprintf (stderr, "Error opendir'ing %s: %s\n", + path, strerror(errno)); + return 0; + } + + char *filenameOffset; + + strcpy(nameBuffer, path); + strcat(nameBuffer, "/"); + + filenameOffset = nameBuffer + strlen(nameBuffer); + + for (;;) { + de = readdir(dir); + + if (de == NULL) { + break; + } + + if (0 == strcmp(de->d_name, ".") + || 0 == strcmp(de->d_name, "..") + || 0 == strcmp(de->d_name, "lost+found") + ) { + continue; + } + + strcpy(filenameOffset, de->d_name); + bool noBackup = false; + + /* See if this is a path we should skip. */ + for (i = 0; SKIP_PATHS[i].path; i++) { + if (strcmp(SKIP_PATHS[i].path, nameBuffer) == 0) { + if (SKIP_PATHS[i].type == SPECIAL_NO_BACKUP) { + // In this case we aren't backing up the directory -- + // we do want to wipe its contents, but not the + // directory itself, since the restore file won't + // contain the directory. + noBackup = true; + } + break; + } + } + if (!noBackup && SKIP_PATHS[i].path != NULL) { + continue; + } + + ret = lstat (nameBuffer, &statBuffer); + + if (ret != 0) { + fprintf(stderr, "warning -- stat() error on '%s': %s\n", + nameBuffer, strerror(errno)); + continue; + } + + if(S_ISDIR(statBuffer.st_mode)) { + int i; + char *newpath; + + newpath = strdup(nameBuffer); + if (wipe(newpath) == 0) { + free(newpath); + closedir(dir); + return 0; + } + + if (!noBackup) { + ret = rmdir(newpath); + if (ret != 0) { + fprintf(stderr, "warning -- rmdir() error on '%s': %s\n", + newpath, strerror(errno)); + } + } + + free(newpath); + + strcpy(nameBuffer, path); + strcat(nameBuffer, "/"); + + } else { + ret = unlink(nameBuffer); + + if (ret != 0) { + fprintf(stderr, "warning -- unlink() error on '%s': %s\n", + nameBuffer, strerror(errno)); + } + } + } + + closedir(dir); + + return 1; +} + +static int write_int32(FILE* fh, int32_t val) +{ + int res = fwrite(&val, 1, sizeof(val), fh); + if (res != sizeof(val)) { + fprintf(stderr, "unable to write int32 (%d bytes): %s\n", res, strerror(errno)); + return 0; + } + + return 1; +} + +static int write_int64(FILE* fh, int64_t val) +{ + int res = fwrite(&val, 1, sizeof(val), fh); + if (res != sizeof(val)) { + fprintf(stderr, "unable to write int64 (%d bytes): %s\n", res, strerror(errno)); + return 0; + } + + return 1; +} + +static int copy_file(FILE* dest, FILE* src, off_t size, const char* destName, + const char* srcName) +{ + errno = 0; + + off_t origSize = size; + + while (size > 0) { + int amt = size > (off_t)sizeof(copyBuffer) ? sizeof(copyBuffer) : (int)size; + int readLen = fread(copyBuffer, 1, amt, src); + if (readLen <= 0) { + if (srcName != NULL) { + fprintf(stderr, "unable to read source (%d of %ld bytes) file '%s': %s\n", + amt, origSize, srcName, errno != 0 ? strerror(errno) : "unexpected EOF"); + } else { + fprintf(stderr, "unable to read buffer (%d of %ld bytes): %s\n", + amt, origSize, errno != 0 ? strerror(errno) : "unexpected EOF"); + } + return 0; + } + int writeLen = fwrite(copyBuffer, 1, readLen, dest); + if (writeLen != readLen) { + if (destName != NULL) { + fprintf(stderr, "unable to write file (%d of %d bytes) '%s': '%s'\n", + writeLen, readLen, destName, strerror(errno)); + } else { + fprintf(stderr, "unable to write buffer (%d of %d bytes): '%s'\n", + writeLen, readLen, strerror(errno)); + } + return 0; + } + size -= readLen; + } + return 1; +} + +#define TYPE_END 0 +#define TYPE_DIR 1 +#define TYPE_FILE 2 + +static int write_header(FILE* fh, int type, const char* path, const struct stat* st) +{ + int pathLen = strlen(path); + if (!write_int32(fh, type)) return 0; + if (!write_int32(fh, pathLen)) return 0; + if (fwrite(path, 1, pathLen, fh) != (size_t)pathLen) { + fprintf(stderr, "unable to write: %s\n", strerror(errno)); + return 0; + } + + if (!write_int32(fh, st->st_uid)) return 0; + if (!write_int32(fh, st->st_gid)) return 0; + if (!write_int32(fh, st->st_mode)) return 0; + if (!write_int64(fh, ((int64_t)st->st_atime)*1000*1000*1000)) return 0; + if (!write_int64(fh, ((int64_t)st->st_mtime)*1000*1000*1000)) return 0; + if (!write_int64(fh, ((int64_t)st->st_ctime)*1000*1000*1000)) return 0; + + return 1; +} + +static int backup_dir(FILE* fh, const char* srcPath) +{ + DIR *dir; + struct dirent *de; + char* fullPath = NULL; + int srcLen = strlen(srcPath); + int result = 1; + int i; + + dir = opendir(srcPath); + + if (dir == NULL) { + fprintf (stderr, "error opendir'ing '%s': %s\n", + srcPath, strerror(errno)); + return 0; + } + + for (;;) { + de = readdir(dir); + + if (de == NULL) { + break; + } + + if (0 == strcmp(de->d_name, ".") + || 0 == strcmp(de->d_name, "..") + || 0 == strcmp(de->d_name, "lost+found") + ) { + continue; + } + + if (fullPath == NULL) { + free(fullPath); + } + fullPath = (char*)malloc(srcLen + strlen(de->d_name) + 2); + strcpy(fullPath, srcPath); + fullPath[srcLen] = '/'; + strcpy(fullPath+srcLen+1, de->d_name); + + /* See if this is a path we should skip. */ + for (i = 0; SKIP_PATHS[i].path; i++) { + if (strcmp(SKIP_PATHS[i].path, fullPath) == 0) { + break; + } + } + if (SKIP_PATHS[i].path != NULL) { + continue; + } + + int ret = lstat(fullPath, &statBuffer); + + if (ret != 0) { + fprintf(stderr, "stat() error on '%s': %s\n", + fullPath, strerror(errno)); + result = 0; + goto done; + } + + if(S_ISDIR(statBuffer.st_mode)) { + printf("Processing dir %s...\n", fullPath); + + if (write_header(fh, TYPE_DIR, fullPath, &statBuffer) == 0) { + result = 0; + goto done; + } + if (backup_dir(fh, fullPath) == 0) { + result = 0; + goto done; + } + } else { + printf("Processing file %s...\n", fullPath); + + if (write_header(fh, TYPE_FILE, fullPath, &statBuffer) == 0) { + result = 0; + goto done; + } + + off_t size = statBuffer.st_size; + if (!write_int64(fh, size)) { + result = 0; + goto done; + } + + FILE* src = fopen(fullPath, "r"); + if (src == NULL) { + fprintf(stderr, "unable to open source file '%s': %s\n", + fullPath, strerror(errno)); + result = 0; + goto done; + } + + int copyres = copy_file(fh, src, size, NULL, fullPath); + fclose(src); + if (!copyres) { + result = 0; + goto done; + } + } + } + +done: + if (fullPath != NULL) { + free(fullPath); + } + + closedir(dir); + + return result; +} + +static int backup_data(const char* destPath) +{ + int res = -1; + + FILE* fh = fopen(destPath, "w"); + if (fh == NULL) { + fprintf(stderr, "unable to open destination '%s': %s\n", + destPath, strerror(errno)); + return -1; + } + + printf("Backing up /data to %s...\n", destPath); + + if (!write_int32(fh, FILE_VERSION)) goto done; + if (!backup_dir(fh, "/data")) goto done; + if (!write_int32(fh, 0)) goto done; + + res = 0; + +done: + if (fflush(fh) != 0) { + fprintf(stderr, "error flushing destination '%s': %s\n", + destPath, strerror(errno)); + res = -1; + goto donedone; + } + if (fsync(fileno(fh)) != 0) { + fprintf(stderr, "error syncing destination '%s': %s\n", + destPath, strerror(errno)); + res = -1; + goto donedone; + } + fclose(fh); + sync(); + +donedone: + return res; +} + +static int32_t read_int32(FILE* fh, int32_t defVal) +{ + int32_t val; + if (fread(&val, 1, sizeof(val), fh) != sizeof(val)) { + fprintf(stderr, "unable to read: %s\n", strerror(errno)); + return defVal; + } + + return val; +} + +static int64_t read_int64(FILE* fh, int64_t defVal) +{ + int64_t val; + if (fread(&val, 1, sizeof(val), fh) != sizeof(val)) { + fprintf(stderr, "unable to read: %s\n", strerror(errno)); + return defVal; + } + + return val; +} + +static int read_header(FILE* fh, int* type, char** path, struct stat* st) +{ + *type = read_int32(fh, -1); + if (*type == TYPE_END) { + return 1; + } + + if (*type < 0) { + fprintf(stderr, "bad token %d in restore file\n", *type); + return 0; + } + + int32_t pathLen = read_int32(fh, -1); + if (pathLen <= 0) { + fprintf(stderr, "bad path length %d in restore file\n", pathLen); + return 0; + } + char* readPath = (char*)malloc(pathLen+1); + if (fread(readPath, 1, pathLen, fh) != (size_t)pathLen) { + fprintf(stderr, "truncated path in restore file\n"); + free(readPath); + return 0; + } + readPath[pathLen] = 0; + *path = readPath; + + st->st_uid = read_int32(fh, -1); + if (st->st_uid == (uid_t)-1) { + fprintf(stderr, "bad uid in restore file at '%s'\n", readPath); + return 0; + } + st->st_gid = read_int32(fh, -1); + if (st->st_gid == (gid_t)-1) { + fprintf(stderr, "bad gid in restore file at '%s'\n", readPath); + return 0; + } + st->st_mode = read_int32(fh, -1); + if (st->st_mode == (mode_t)-1) { + fprintf(stderr, "bad mode in restore file at '%s'\n", readPath); + return 0; + } + int64_t ltime = read_int64(fh, -1); + if (ltime < 0) { + fprintf(stderr, "bad atime in restore file at '%s'\n", readPath); + return 0; + } + st->st_atime = (time_t)(ltime/1000/1000/1000); + ltime = read_int64(fh, -1); + if (ltime < 0) { + fprintf(stderr, "bad mtime in restore file at '%s'\n", readPath); + return 0; + } + st->st_mtime = (time_t)(ltime/1000/1000/1000); + ltime = read_int64(fh, -1); + if (ltime < 0) { + fprintf(stderr, "bad ctime in restore file at '%s'\n", readPath); + return 0; + } + st->st_ctime = (time_t)(ltime/1000/1000/1000); + + st->st_mode &= (S_IRWXU|S_IRWXG|S_IRWXO); + + return 1; +} + +static int restore_data(const char* srcPath) +{ + int res = -1; + + FILE* fh = fopen(srcPath, "r"); + if (fh == NULL) { + fprintf(stderr, "Unable to open source '%s': %s\n", + srcPath, strerror(errno)); + return -1; + } + + if (read_int32(fh, 0) != (int32_t)FILE_VERSION) { + fprintf(stderr, "Restore file has bad version\n"); + goto done; + } + + printf("Wiping contents of /data...\n"); + if (!wipe("/data")) { + goto done; + } + + printf("Restoring from %s to /data...\n", srcPath); + + while (1) { + int type; + char* path = NULL; + if (read_header(fh, &type, &path, &statBuffer) == 0) { + goto done; + } + if (type == 0) { + break; + } + + const char* typeName = "?"; + + if (type == TYPE_DIR) { + typeName = "dir"; + + printf("Processing dir %s...\n", path); + + if (mkdir(path, statBuffer.st_mode) != 0) { + if (errno != EEXIST) { + fprintf(stderr, "unable to create directory '%s': %s\n", + path, strerror(errno)); + free(path); + goto done; + } + } + + } else if (type == TYPE_FILE) { + typeName = "file"; + off_t size = read_int64(fh, -1); + if (size < 0) { + fprintf(stderr, "bad file size %ld in restore file\n", size); + free(path); + goto done; + } + + printf("Processing file %s...\n", path); + + FILE* dest = fopen(path, "w"); + if (dest == NULL) { + fprintf(stderr, "unable to open destination file '%s': %s\n", + path, strerror(errno)); + free(path); + goto done; + } + + int copyres = copy_file(dest, fh, size, path, NULL); + fclose(dest); + if (!copyres) { + free(path); + goto done; + } + + } else { + fprintf(stderr, "unknown node type %d\n", type); + goto done; + } + + // Do this even for directories, since the dir may have already existed + // so we need to make sure it gets the correct mode. + if (chmod(path, statBuffer.st_mode&(S_IRWXU|S_IRWXG|S_IRWXO)) != 0) { + fprintf(stderr, "unable to chmod destination %s '%s' to 0x%x: %s\n", + typeName, path, statBuffer.st_mode, strerror(errno)); + free(path); + goto done; + } + + if (chown(path, statBuffer.st_uid, statBuffer.st_gid) != 0) { + fprintf(stderr, "unable to chown destination %s '%s' to uid %d / gid %d: %s\n", + typeName, path, (int)statBuffer.st_uid, (int)statBuffer.st_gid, strerror(errno)); + free(path); + goto done; + } + + struct utimbuf timbuf; + timbuf.actime = statBuffer.st_atime; + timbuf.modtime = statBuffer.st_mtime; + if (utime(path, &timbuf) != 0) { + fprintf(stderr, "unable to utime destination %s '%s': %s\n", + typeName, path, strerror(errno)); + free(path); + goto done; + } + + + free(path); + } + + res = 0; + +done: + fclose(fh); + + return res; +} + +static void show_help(const char *cmd) +{ + fprintf(stderr,"Usage: %s [options] [backup-file-path]\n", cmd); + + fprintf(stderr, "options include:\n" + " -r Perform restore of previous backup.\n"); +} + +} /* namespace android */ + +int main (int argc, char **argv) +{ + int restore = 0; + + if (getuid() != AID_ROOT) { + fprintf(stderr, "error -- %s must run as root\n", argv[0]); + exit(-1); + } + + if (argc == 2 && 0 == strcmp(argv[1], "--help")) { + android::show_help(argv[0]); + exit(0); + } + + for (;;) { + int ret; + + ret = getopt(argc, argv, "r"); + + if (ret < 0) { + break; + } + + switch(ret) { + case 'r': + restore = 1; + break; + + default: + fprintf(stderr,"Unrecognized Option\n"); + android::show_help(argv[0]); + exit(-1); + break; + } + } + + const char* backupFile = "/sdcard/backup.dat"; + + if (argc > optind) { + backupFile = argv[optind]; + optind++; + if (argc != optind) { + fprintf(stderr, "Too many arguments\n"); + android::show_help(argv[0]); + exit(-1); + } + } + + printf("Stopping system...\n"); + property_set("ctl.stop", "runtime"); + property_set("ctl.stop", "zygote"); + sleep(1); + + int res; + if (restore) { + res = android::restore_data(backupFile); + if (res != 0) { + // Don't restart system, since the data partition is hosed. + return res; + } + printf("Restore complete! Restarting system, cross your fingers...\n"); + } else { + res = android::backup_data(backupFile); + if (res == 0) { + printf("Backup complete! Restarting system...\n"); + } else { + printf("Restarting system...\n"); + } + } + + property_set("ctl.start", "zygote"); + property_set("ctl.start", "runtime"); +} |