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

(was doing zillions of 1-byte write syscalls)



git-svn-id: svn://busybox.net/trunk/busybox@16083 69ca8d6d-28ef-0310-b511-8ec308f3f277

2 files changed, 71 insertions, 59 deletions

diff --git a/archival/tar.c b/archival/tar.c
index 0b5720f3b..91232bcf3 100644
--- a/archival/tar.c
+++ b/archival/tar.c
@@ -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;
                 }
diff --git a/libbb/recursive_action.c b/libbb/recursive_action.c
index d491b781b..28a493403 100644
--- a/libbb/recursive_action.c
+++ b/libbb/recursive_action.c
@@ -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;