/* Write out a tar header for the specified file/directory/whatever */ static int writeTarHeader(struct TarBallInfo *tbInfo, const char *header_name, const char *fileName, struct stat *statbuf) { struct tar_header_t header; memset(&header, 0, sizeof(header)); strncpy(header.name, header_name, sizeof(header.name)); /* POSIX says to mask mode with 07777. */ PUT_OCTAL(header.mode, statbuf->st_mode & 07777); PUT_OCTAL(header.uid, statbuf->st_uid); PUT_OCTAL(header.gid, statbuf->st_gid); memset(header.size, '0', sizeof(header.size)-1); /* Regular file size is handled later */ /* users report that files with negative st_mtime cause trouble, so: */ PUT_OCTAL(header.mtime, statbuf->st_mtime >= 0 ? statbuf->st_mtime : 0); /* Enter the user and group names */ safe_strncpy(header.uname, get_cached_username(statbuf->st_uid), sizeof(header.uname)); safe_strncpy(header.gname, get_cached_groupname(statbuf->st_gid), sizeof(header.gname)); if (tbInfo->hlInfo) { /* This is a hard link */ header.typeflag = LNKTYPE; strncpy(header.linkname, tbInfo->hlInfo->name, sizeof(header.linkname)); #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS /* Write out long linkname if needed */ if (header.linkname[sizeof(header.linkname)-1]) writeLongname(tbInfo->tarFd, GNULONGLINK, tbInfo->hlInfo->name, 0); #endif } else if (S_ISLNK(statbuf->st_mode)) { char *lpath = xmalloc_readlink_or_warn(fileName); if (!lpath) return FALSE; header.typeflag = SYMTYPE; strncpy(header.linkname, lpath, sizeof(header.linkname)); #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS /* Write out long linkname if needed */ if (header.linkname[sizeof(header.linkname)-1]) writeLongname(tbInfo->tarFd, GNULONGLINK, lpath, 0); #else /* If it is larger than 100 bytes, bail out */ if (header.linkname[sizeof(header.linkname)-1]) { free(lpath); bb_error_msg("names longer than "NAME_SIZE_STR" chars not supported"); return FALSE; } #endif free(lpath); } else if (S_ISDIR(statbuf->st_mode)) { header.typeflag = DIRTYPE; /* Append '/' only if there is a space for it */ if (!header.name[sizeof(header.name)-1]) header.name[strlen(header.name)] = '/'; } else if (S_ISCHR(statbuf->st_mode)) { header.typeflag = CHRTYPE; PUT_OCTAL(header.devmajor, major(statbuf->st_rdev)); PUT_OCTAL(header.devminor, minor(statbuf->st_rdev)); } else if (S_ISBLK(statbuf->st_mode)) { header.typeflag = BLKTYPE; PUT_OCTAL(header.devmajor, major(statbuf->st_rdev)); PUT_OCTAL(header.devminor, minor(statbuf->st_rdev)); } else if (S_ISFIFO(statbuf->st_mode)) { header.typeflag = FIFOTYPE; } else if (S_ISREG(statbuf->st_mode)) { /* header.size field is 12 bytes long */ /* Does octal-encoded size fit? */ uoff_t filesize = statbuf->st_size; if (sizeof(filesize) <= 4 || filesize <= (uoff_t)0777777777777LL ) { PUT_OCTAL(header.size, filesize); } /* Does base256-encoded size fit? * It always does unless off_t is wider than 64 bits. */ else if (ENABLE_FEATURE_TAR_GNU_EXTENSIONS #if ULLONG_MAX > 0xffffffffffffffffLL /* 2^64-1 */ && (filesize <= 0x3fffffffffffffffffffffffLL) #endif ) { /* GNU tar uses "base-256 encoding" for very large numbers. * Encoding is binary, with highest bit always set as a marker * and sign in next-highest bit: * 80 00 .. 00 - zero * bf ff .. ff - largest positive number * ff ff .. ff - minus 1 * c0 00 .. 00 - smallest negative number */ char *p8 = header.size + sizeof(header.size); do { *--p8 = (uint8_t)filesize; filesize >>= 8; } while (p8 != header.size); *p8 |= 0x80; } else {
static int writeTarHeader(struct TarBallInfo *tbInfo, const char *header_name, const char *fileName, struct stat *statbuf) { struct TarHeader header; if (sizeof(header) != 512) BUG_tar_header_size(); memset(&header, 0, sizeof(struct TarHeader)); strncpy(header.name, header_name, sizeof(header.name)); /* POSIX says to mask mode with 07777. */ PUT_OCTAL(header.mode, statbuf->st_mode & 07777); PUT_OCTAL(header.uid, statbuf->st_uid); PUT_OCTAL(header.gid, statbuf->st_gid); memset(header.size, '0', sizeof(header.size)-1); /* Regular file size is handled later */ PUT_OCTAL(header.mtime, statbuf->st_mtime); /* Enter the user and group names */ safe_strncpy(header.uname, get_cached_username(statbuf->st_uid), sizeof(header.uname)); safe_strncpy(header.gname, get_cached_groupname(statbuf->st_gid), sizeof(header.gname)); if (tbInfo->hlInfo) { /* This is a hard link */ header.typeflag = LNKTYPE; strncpy(header.linkname, tbInfo->hlInfo->name, sizeof(header.linkname)); #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS /* Write out long linkname if needed */ if (header.linkname[sizeof(header.linkname)-1]) writeLongname(tbInfo->tarFd, GNULONGLINK, tbInfo->hlInfo->name, 0); #endif } else if (S_ISLNK(statbuf->st_mode)) { char *lpath = xmalloc_readlink_or_warn(fileName); if (!lpath) return FALSE; header.typeflag = SYMTYPE; strncpy(header.linkname, lpath, sizeof(header.linkname)); #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS /* Write out long linkname if needed */ if (header.linkname[sizeof(header.linkname)-1]) writeLongname(tbInfo->tarFd, GNULONGLINK, lpath, 0); #else /* If it is larger than 100 bytes, bail out */ if (header.linkname[sizeof(header.linkname)-1]) { free(lpath); bb_error_msg("names longer than "NAME_SIZE_STR" chars not supported"); return FALSE; } #endif free(lpath); } else if (S_ISDIR(statbuf->st_mode)) { header.typeflag = DIRTYPE; /* Append '/' only if there is a space for it */ if (!header.name[sizeof(header.name)-1]) header.name[strlen(header.name)] = '/'; } else if (S_ISCHR(statbuf->st_mode)) { header.typeflag = CHRTYPE; PUT_OCTAL(header.devmajor, major(statbuf->st_rdev)); PUT_OCTAL(header.devminor, minor(statbuf->st_rdev)); } else if (S_ISBLK(statbuf->st_mode)) { header.typeflag = BLKTYPE; PUT_OCTAL(header.devmajor, major(statbuf->st_rdev)); PUT_OCTAL(header.devminor, minor(statbuf->st_rdev)); } else if (S_ISFIFO(statbuf->st_mode)) { header.typeflag = FIFOTYPE; } else if (S_ISREG(statbuf->st_mode)) { if (sizeof(statbuf->st_size) > 4 && statbuf->st_size > (off_t)0777777777777LL ) { bb_error_msg_and_die("cannot store file '%s' " "of size %"OFF_FMT"d, aborting", fileName, statbuf->st_size); } header.typeflag = REGTYPE; PUT_OCTAL(header.size, statbuf->st_size); } else { bb_error_msg("%s: unknown file type", fileName); return FALSE; } #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS /* Write out long name if needed */ /* (we, like GNU tar, output long linkname *before* long name) */ if (header.name[sizeof(header.name)-1]) writeLongname(tbInfo->tarFd, GNULONGNAME, header_name, S_ISDIR(statbuf->st_mode)); #endif /* Now write the header out to disk */ chksum_and_xwrite(tbInfo->tarFd, &header); /* Now do the verbose thing (or not) */ if (tbInfo->verboseFlag) { FILE *vbFd = stdout; /* If archive goes to stdout, verbose goes to stderr */ if (tbInfo->tarFd == STDOUT_FILENO) vbFd = stderr; /* GNU "tar cvvf" prints "extended" listing a-la "ls -l" */ /* We don't have such excesses here: for us "v" == "vv" */ /* '/' is probably a GNUism */ fprintf(vbFd, "%s%s\n", header_name, S_ISDIR(statbuf->st_mode) ? "/" : ""); } return TRUE; }