tar,smemcap: commonalyze checksumming code for tar header

function                                             old     new   delta
chksum_and_xwrite_tar_header                           -      99     +99
writeheader                                          280     199     -81
chksum_and_xwrite                                    102       -    -102
------------------------------------------------------------------------------
(add/remove: 2/1 grow/shrink: 0/1 up/down: 99/-183)           Total: -84 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 1 insertions, 15 deletions

diff --git a/procps/smemcap.c b/procps/smemcap.c
index 2f8ab192e..2f1897dae 100644
--- a/procps/smemcap.c
+++ b/procps/smemcap.c
@@ -29,7 +29,6 @@ struct fileblock {
 static void writeheader(const char *path, struct stat *sb, int type)
 {
 	struct tar_header_t header;
-	int i, sum;
 
 	memset(&header, 0, TAR_BLOCK_SIZE);
 	strcpy(header.name, path);
@@ -40,20 +39,7 @@ static void writeheader(const char *path, struct stat *sb, int type)
 	sprintf(header.size, "%o", (unsigned)sb->st_size);
 	sprintf(header.mtime, "%llo", sb->st_mtime & 077777777777LL);
 	header.typeflag = type;
-	strcpy(header.magic, "ustar  "); /* like GNU tar */
-
-	/* Calculate and store the checksum (the sum of all of the bytes of
-	 * the header). The checksum field must be filled with blanks for the
-	 * calculation. The checksum field is formatted differently from the
-	 * other fields: it has 6 digits, a NUL, then a space -- rather than
-	 * digits, followed by a NUL like the other fields... */
-	header.chksum[7] = ' ';
-	sum = ' ' * 7;
-	for (i = 0; i < TAR_BLOCK_SIZE; i++)
-		sum += ((unsigned char*)&header)[i];
-	sprintf(header.chksum, "%06o", sum);
-
-	xwrite(STDOUT_FILENO, &header, TAR_BLOCK_SIZE);
+	chksum_and_xwrite_tar_header(STDOUT_FILENO, &header);
 }
 
 static void archivefile(const char *path)