bsdiff-portable

commit bd45371d268cb6da6692ab0b4efb76c8ee7bef40
parent f4eed7a708e3bc2151707b9f5006e6afbbfb055b
Author: Matthew Endsley <mendsley@gmail.com>
Date:   Thu, 24 Sep 2020 00:12:28 +1000

Replace header buf with struct

Diffstat:
M
bsdiff.c
 | 
17
+++++++----------
M
bsdiff.h
 | 
7
+++++++
M
bspatch.c
 | 
2
+-

3 files changed, 15 insertions(+), 11 deletions(-)
diff --git a/bsdiff.c b/bsdiff.c
@@ -63,7 +63,7 @@ main(int argc, char **argv)
 	off_t dblen, eblen;
 	uint8_t *db, *eb;
 	uint8_t buf[8];
-	uint8_t header[32];
+	struct bsdiff_header header = {"BSDIFF40", 0, 0, 0};
 	FILE *pf;
 	BZFILE *pfbz2;
 	int bz2err;
@@ -123,12 +123,9 @@ main(int argc, char **argv)
 		32	??	Bzip2ed ctrl block
 		??	??	Bzip2ed diff block
 		??	??	Bzip2ed extra block */
-	memcpy(header, "BSDIFF40", 8);
-	offtout(0, header + 8);
-	offtout(0, header + 16);
-	offtout(newsize, header + 24);
-	if (fwrite(header, 32, 1, pf) == 0)
-		err(1, "fwrite(%s, %lld)", argv[3], (long long)32);
+	header.new_file_len = newsize;
+	if (fwrite(&header, 1, sizeof(header), pf) != 32)
+		err(1, "fwrite(%s, %zu)", argv[3], sizeof(header));
 
 	/* Compute the differences, writing ctrl as we go */
 	if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
@@ -240,7 +237,7 @@ main(int argc, char **argv)
 	/* Compute size of compressed ctrl data */
 	if ((len = ftello(pf)) == -1)
 		err(1, "ftello");
-	offtout(len - 32, header + 8);
+	header.ctrl_block_len = len - 32;
 
 	/* Write compressed diff data */
 	if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
@@ -255,7 +252,7 @@ main(int argc, char **argv)
 	/* Compute size of compressed diff data */
 	if ((newsize = ftello(pf)) == -1)
 		err(1, "ftello");
-	offtout(newsize - len, header + 16);
+	header.diff_block_len = newsize - len;
 
 	/* Write compressed extra data */
 	if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
@@ -270,7 +267,7 @@ main(int argc, char **argv)
 	/* Seek to the beginning, write the header, and close the file */
 	if (fseeko(pf, 0, SEEK_SET))
 		err(1, "fseeko");
-	if (fwrite(header, 32, 1, pf) != 1)
+	if (fwrite(&header, 1, sizeof(header), pf) != 32)
 		err(1, "fwrite(%s)", argv[3]);
 	if (fclose(pf))
 		err(1, "fclose");
diff --git a/bsdiff.h b/bsdiff.h
@@ -35,6 +35,13 @@
 
 #define MIN(x, y) (((x) < (y)) ? (x) : (y))
 
+struct bsdiff_header {
+	uint8_t magic[8];
+	off_t	ctrl_block_len;
+	off_t	diff_block_len;
+	off_t	new_file_len;
+};
+
 void		split(off_t *, off_t *, off_t, off_t, off_t);
 void		qsufsort(off_t *, off_t *, uint8_t *, off_t);
 off_t		matchlen(uint8_t *, off_t, uint8_t *, off_t);
diff --git a/bspatch.c b/bspatch.c
@@ -80,7 +80,7 @@ main(int argc, char **argv)
 #endif
 	/* Open patch file */
 	if ((f = fopen(argv[3], "r")) == NULL)
-		err(1, "%s: fopen", argv[3]);
+		err(1, "fopen(%s)", argv[3]);
 	/* Open the new file */
 	if ((fd = open(argv[2], O_CREAT|O_TRUNC|O_WRONLY, 0666)) == -1)
 		err(1, "open(%s)", argv[2]);