tar: fix "xopen with O_CREAT" warning, improve zero padding write
authorDenis Vlasenko <vda.linux@googlemail.com>
Sat, 9 Sep 2006 12:49:03 +0000 (12:49 -0000)
committerDenis Vlasenko <vda.linux@googlemail.com>
Sat, 9 Sep 2006 12:49:03 +0000 (12:49 -0000)
(was doing zillions of 1-byte write syscalls)

archival/tar.c
libbb/recursive_action.c

index 0b5720f3beaae04419614e56abe336f2fc1513a5..91232bcf38889cc01d025fc824ef9f2a51d57405 100644 (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;
                }
index d491b781b073f69e942965590e26c5c02c524e4c..28a493403276e98e66503fc7251a8bb7e0852617 100644 (file)
  * 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;