tar: fix "xopen with O_CREAT" warning, improve zero padding write

(was doing zillions of 1-byte write syscalls)
This commit is contained in:
Denis Vlasenko 2006-09-09 12:49:03 +00:00
parent d5d614c5f4
commit 0c45bb23d2
2 changed files with 71 additions and 59 deletions

View File

@ -84,7 +84,6 @@ struct HardLinkInfo {
/* Some info to be carried along when creating a new tarball */
struct TarBallInfo {
char *fileName; /* File name of the tarball */
int tarFd; /* Open-for-write file descriptor
for the tarball */
struct stat statBuf; /* Stat info for the tarball, letting
@ -117,18 +116,18 @@ typedef enum TarFileType TarFileType;
/* Might be faster (and bigger) if the dev/ino were stored in numeric order;) */
static void addHardLinkInfo(HardLinkInfo ** hlInfoHeadPtr,
struct stat *statbuf,
const char *name)
const char *fileName)
{
/* Note: hlInfoHeadPtr can never be NULL! */
HardLinkInfo *hlInfo;
hlInfo = (HardLinkInfo *) xmalloc(sizeof(HardLinkInfo) + strlen(name));
hlInfo = xmalloc(sizeof(HardLinkInfo) + strlen(fileName));
hlInfo->next = *hlInfoHeadPtr;
*hlInfoHeadPtr = hlInfo;
hlInfo->dev = statbuf->st_dev;
hlInfo->ino = statbuf->st_ino;
hlInfo->linkCount = statbuf->st_nlink;
strcpy(hlInfo->name, name);
strcpy(hlInfo->name, fileName);
}
static void freeHardLinkInfo(HardLinkInfo ** hlInfoHeadPtr)
@ -156,7 +155,7 @@ static HardLinkInfo *findHardLinkInfo(HardLinkInfo * hlInfo, struct stat *statbu
break;
hlInfo = hlInfo->next;
}
return (hlInfo);
return hlInfo;
}
/* Put an octal string into the specified buffer.
@ -193,9 +192,29 @@ static int putOctal(char *cp, int len, long value)
return TRUE;
}
/* Pad file to TAR_BLOCK_SIZE with zeros */
static void block_write_zeroes(int fd, size_t size)
{
char zerobuf[TAR_BLOCK_SIZE];
memset(zerobuf, 0, size);
/* No point in trying to continue on error */
if (full_write(fd, zerobuf, size) < 0)
bb_perror_msg_and_die("write");
}
static size_t pad_block_write(int fd, size_t size)
{
size_t rem = (TAR_BLOCK_SIZE - size) & (TAR_BLOCK_SIZE-1);
if (rem) {
block_write_zeroes(fd, rem);
size += rem;
}
return size;
}
/* Write out a tar header for the specified file/directory/whatever */
static int writeTarHeader(struct TarBallInfo *tbInfo,
const char *header_name, const char *real_name, struct stat *statbuf)
const char *header_name, const char *fileName, struct stat *statbuf)
{
long chksum = 0;
struct TarHeader header;
@ -225,10 +244,10 @@ static int writeTarHeader(struct TarBallInfo *tbInfo,
strncpy(header.linkname, tbInfo->hlInfo->name,
sizeof(header.linkname));
} else if (S_ISLNK(statbuf->st_mode)) {
char *lpath = xreadlink(real_name);
char *lpath = xreadlink(fileName);
if (!lpath) /* Already printed err msg inside xreadlink() */
return (FALSE);
return FALSE;
header.typeflag = SYMTYPE;
strncpy(header.linkname, lpath, sizeof(header.linkname));
free(lpath);
@ -253,8 +272,8 @@ static int writeTarHeader(struct TarBallInfo *tbInfo,
header.typeflag = REGTYPE;
putOctal(header.size, sizeof(header.size), statbuf->st_size);
} else {
bb_error_msg("%s: Unknown file type", real_name);
return (FALSE);
bb_error_msg("%s: unknown file type", fileName);
return FALSE;
}
/* Calculate and store the checksum (i.e., the sum of all of the bytes of
@ -269,16 +288,15 @@ static int writeTarHeader(struct TarBallInfo *tbInfo,
putOctal(header.chksum, 7, chksum);
/* Now write the header out to disk */
if ((size = full_write(tbInfo->tarFd, (char *) &header,
sizeof(struct TarHeader))) < 0)
{
bb_error_msg(bb_msg_io_error, real_name);
return (FALSE);
size = full_write(tbInfo->tarFd, (char *) &header,
sizeof(struct TarHeader));
if (size < 0) {
bb_error_msg(bb_msg_io_error, fileName);
return FALSE;
}
/* Pad the header up to the tar block size */
for (; size < TAR_BLOCK_SIZE; size++) {
write(tbInfo->tarFd, "\0", 1);
}
size = pad_block_write(tbInfo->tarFd, size);
/* Now do the verbose thing (or not) */
if (tbInfo->verboseFlag) {
@ -290,7 +308,7 @@ static int writeTarHeader(struct TarBallInfo *tbInfo,
fprintf(vbFd, "%s\n", header.name);
}
return (TRUE);
return TRUE;
}
# ifdef CONFIG_FEATURE_TAR_FROM
@ -328,11 +346,11 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf,
int inputFileFd = -1;
/*
** Check to see if we are dealing with a hard link.
** If so -
** Treat the first occurance of a given dev/inode as a file while
** treating any additional occurances as hard links. This is done
** by adding the file information to the HardLinkInfo linked list.
* Check to see if we are dealing with a hard link.
* If so -
* Treat the first occurance of a given dev/inode as a file while
* treating any additional occurances as hard links. This is done
* by adding the file information to the HardLinkInfo linked list.
*/
tbInfo->hlInfo = NULL;
if (statbuf->st_nlink > 1) {
@ -344,7 +362,7 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf,
/* It is against the rules to archive a socket */
if (S_ISSOCK(statbuf->st_mode)) {
bb_error_msg("%s: socket ignored", fileName);
return (TRUE);
return TRUE;
}
/* It is a bad idea to store the archive we are in the process of creating,
@ -353,7 +371,7 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf,
if (tbInfo->statBuf.st_dev == statbuf->st_dev &&
tbInfo->statBuf.st_ino == statbuf->st_ino) {
bb_error_msg("%s: file is the archive; skipping", fileName);
return (TRUE);
return TRUE;
}
header_name = fileName;
@ -361,7 +379,7 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf,
static int alreadyWarned = FALSE;
if (alreadyWarned == FALSE) {
bb_error_msg("Removing leading '/' from member names");
bb_error_msg("removing leading '/' from member names");
alreadyWarned = TRUE;
}
header_name++;
@ -369,7 +387,7 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf,
if (strlen(fileName) >= NAME_SIZE) {
bb_error_msg(bb_msg_name_longer_than_foo, NAME_SIZE);
return (TRUE);
return TRUE;
}
if (header_name[0] == '\0')
@ -382,21 +400,20 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf,
/* Is this a regular file? */
if ((tbInfo->hlInfo == NULL) && (S_ISREG(statbuf->st_mode))) {
/* open the file we want to archive, and make sure all is well */
if ((inputFileFd = open(fileName, O_RDONLY)) < 0) {
bb_perror_msg("%s: Cannot open", fileName);
return (FALSE);
bb_perror_msg("%s: cannot open", fileName);
return FALSE;
}
}
/* Add an entry to the tarball */
if (writeTarHeader(tbInfo, header_name, fileName, statbuf) == FALSE) {
return (FALSE);
return FALSE;
}
/* If it was a regular file, write out the body */
if (inputFileFd >= 0 ) {
if (inputFileFd >= 0) {
ssize_t readSize = 0;
/* write the file to the archive */
@ -404,11 +421,10 @@ static int writeFileToTarball(const char *fileName, struct stat *statbuf,
close(inputFileFd);
/* Pad the file up to the tar block size */
for (; (readSize % TAR_BLOCK_SIZE) != 0; readSize++)
write(tbInfo->tarFd, "\0", 1);
readSize = pad_block_write(tbInfo->tarFd, readSize);
}
return (TRUE);
return TRUE;
}
static int writeTarFile(const int tar_fd, const int verboseFlag,
@ -416,9 +432,7 @@ static int writeTarFile(const int tar_fd, const int verboseFlag,
const llist_t *exclude, const int gzip)
{
pid_t gzipPid = 0;
int errorFlag = FALSE;
ssize_t size;
struct TarBallInfo tbInfo;
tbInfo.hlInfoHead = NULL;
@ -430,7 +444,7 @@ static int writeTarFile(const int tar_fd, const int verboseFlag,
/* Store the stat info for the tarball's file, so
* can avoid including the tarball into itself.... */
if (fstat(tbInfo.tarFd, &tbInfo.statBuf) < 0)
bb_perror_msg_and_die("Couldnt stat tar file");
bb_perror_msg_and_die("cannot stat tar file");
if ((ENABLE_FEATURE_TAR_GZIP || ENABLE_FEATURE_TAR_BZIP2) && gzip) {
int gzipDataPipe[2] = { -1, -1 };
@ -440,7 +454,7 @@ static int writeTarFile(const int tar_fd, const int verboseFlag,
if (pipe(gzipDataPipe) < 0 || pipe(gzipStatusPipe) < 0)
bb_perror_msg_and_die("create pipe");
bb_perror_msg_and_die("pipe");
signal(SIGPIPE, SIG_IGN); /* we only want EPIPE on errors */
@ -502,8 +516,8 @@ static int writeTarFile(const int tar_fd, const int verboseFlag,
include = include->link;
}
/* Write two empty blocks to the end of the archive */
for (size = 0; size < (2 * TAR_BLOCK_SIZE); size++)
write(tbInfo.tarFd, "\0", 1);
block_write_zeroes(tbInfo.tarFd, TAR_BLOCK_SIZE);
block_write_zeroes(tbInfo.tarFd, TAR_BLOCK_SIZE);
/* To be pedantically correct, we would check if the tarball
* is smaller than 20 tar blocks, and pad it if it was smaller,
@ -546,10 +560,10 @@ static llist_t *append_file_list_to_list(llist_t *list)
cur = cur->link;
free(tmp);
while ((line = bb_get_chomped_line_from_file(src_stream)) != NULL) {
char *filename_ptr = last_char_is(line, '/');
if (filename_ptr > line)
*filename_ptr = '\0';
llist_add_to(&newlist, line);
char *filename_ptr = last_char_is(line, '/');
if (filename_ptr > line)
*filename_ptr = '\0';
llist_add_to(&newlist, line);
}
fclose(src_stream);
}
@ -569,12 +583,13 @@ static char get_header_tar_Z(archive_handle_t *archive_handle)
if (xread_char(archive_handle->src_fd) != 0x1f ||
xread_char(archive_handle->src_fd) != 0x9d)
{
bb_error_msg_and_die("Invalid magic");
bb_error_msg_and_die("invalid magic");
}
archive_handle->src_fd = open_transformer(archive_handle->src_fd, uncompress);
archive_handle->offset = 0;
while (get_header_tar(archive_handle) == EXIT_SUCCESS);
while (get_header_tar(archive_handle) == EXIT_SUCCESS)
/* nothing */;
/* Can only do one file at a time */
return(EXIT_FAILURE);
@ -828,7 +843,7 @@ int tar_main(int argc, char **argv)
tar_handle->src_fd = fileno(tar_stream);
tar_handle->seek = seek_by_char;
} else {
tar_handle->src_fd = xopen(tar_filename, flags);
tar_handle->src_fd = xopen3(tar_filename, flags, 0666);
}
}
@ -854,14 +869,15 @@ int tar_main(int argc, char **argv)
tar_handle->accept,
tar_handle->reject, zipMode);
} else {
while (get_header_ptr(tar_handle) == EXIT_SUCCESS);
while (get_header_ptr(tar_handle) == EXIT_SUCCESS)
/* nothing */;
/* Check that every file that should have been extracted was */
while (tar_handle->accept) {
if (!find_list_entry(tar_handle->reject, tar_handle->accept->data)
&& !find_list_entry(tar_handle->passed, tar_handle->accept->data))
{
bb_error_msg_and_die("%s: Not found in archive", tar_handle->accept->data);
bb_error_msg_and_die("%s: not found in archive", tar_handle->accept->data);
}
tar_handle->accept = tar_handle->accept->link;
}

View File

@ -23,14 +23,10 @@
* is so stinking huge.
*/
int recursive_action(const char *fileName,
int recurse, int followLinks, int depthFirst,
int (*fileAction) (const char *fileName,
struct stat * statbuf,
void* userData),
int (*dirAction) (const char *fileName,
struct stat * statbuf,
void* userData),
void* userData)
int recurse, int followLinks, int depthFirst,
int (*fileAction) (const char *fileName, struct stat * statbuf, void* userData),
int (*dirAction) (const char *fileName, struct stat * statbuf, void* userData),
void* userData)
{
int status;
struct stat statbuf;