X-Git-Url: https://git.octo.it/?p=git.git;a=blobdiff_plain;f=builtin-tar-tree.c;h=39a61b629367df9dd274acf5fa310b45dd06f126;hp=5f740cf7025bc2a9b46656332c6a54e78ee737e4;hb=HEAD;hpb=4c068a983150b740c3fcf6a33f342ac923abd3f4

diff --git a/builtin-tar-tree.c b/builtin-tar-tree.c
index 5f740cf7..39a61b62 100644
--- a/builtin-tar-tree.c
+++ b/builtin-tar-tree.c
@@ -22,8 +22,10 @@ static unsigned long offset;
 static time_t archive_time;
 
 /* tries hard to write, either succeeds or dies in the attempt */
-static void reliable_write(void *buf, unsigned long size)
+static void reliable_write(const void *data, unsigned long size)
 {
+	const char *buf = data;
+
 	while (size > 0) {
 		long ret = xwrite(1, buf, size);
 		if (ret < 0) {
@@ -47,37 +49,13 @@ static void write_if_needed(void)
 	}
 }
 
-/* acquire the next record from the buffer; user must call write_if_needed() */
-static char *get_record(void)
-{
-	char *p = block + offset;
-	memset(p, 0, RECORDSIZE);
-	offset += RECORDSIZE;
-	return p;
-}
-
-/*
- * The end of tar archives is marked by 1024 nul bytes and after that
- * follows the rest of the block (if any).
- */
-static void write_trailer(void)
-{
-	get_record();
-	write_if_needed();
-	get_record();
-	write_if_needed();
-	while (offset) {
-		get_record();
-		write_if_needed();
-	}
-}
-
 /*
  * queues up writes, so that all our write(2) calls write exactly one
  * full block; pads writes to RECORDSIZE
  */
-static void write_blocked(void *buf, unsigned long size)
+static void write_blocked(const void *data, unsigned long size)
 {
+	const char *buf = data;
 	unsigned long tail;
 
 	if (offset) {
@@ -107,6 +85,21 @@ static void write_blocked(void *buf, unsigned long size)
 	write_if_needed();
 }
 
+/*
+ * The end of tar archives is marked by 2*512 nul bytes and after that
+ * follows the rest of the block (if any).
+ */
+static void write_trailer(void)
+{
+	int tail = BLOCKSIZE - offset;
+	memset(block + offset, 0, tail);
+	reliable_write(block, BLOCKSIZE);
+	if (tail < 2 * RECORDSIZE) {
+		memset(block, 0, offset);
+		reliable_write(block, BLOCKSIZE);
+	}
+}
+
 static void strbuf_append_string(struct strbuf *sb, const char *s)
 {
 	int slen = strlen(s);
@@ -168,8 +161,9 @@ static int get_path_prefix(const struct strbuf *path, int maxlen)
 	int i = path->len;
 	if (i > maxlen)
 		i = maxlen;
-	while (i > 0 && path->buf[i] != '/')
+	do {
 		i--;
+	} while (i > 0 && path->buf[i] != '/');
 	return i;
 }
 
@@ -239,8 +233,8 @@ static void write_entry(const unsigned char *sha1, struct strbuf *path,
 	/* XXX: should we provide more meaningful info here? */
 	sprintf(header.uid, "%07o", 0);
 	sprintf(header.gid, "%07o", 0);
-	strncpy(header.uname, "git", 31);
-	strncpy(header.gname, "git", 31);
+	safe_strncpy(header.uname, "git", sizeof(header.uname));
+	safe_strncpy(header.gname, "git", sizeof(header.gname));
 	sprintf(header.devmajor, "%07o", 0);
 	sprintf(header.devminor, "%07o", 0);
 
@@ -401,3 +395,28 @@ int cmd_tar_tree(int argc, const char **argv, char **envp)
 		return remote_tar(argc, argv);
 	return generate_tar(argc, argv, envp);
 }
+
+/* ustar header + extended global header content */
+#define HEADERSIZE (2 * RECORDSIZE)
+
+int cmd_get_tar_commit_id(int argc, const char **argv, char **envp)
+{
+	char buffer[HEADERSIZE];
+	struct ustar_header *header = (struct ustar_header *)buffer;
+	char *content = buffer + RECORDSIZE;
+	ssize_t n;
+
+	n = xread(0, buffer, HEADERSIZE);
+	if (n < HEADERSIZE)
+		die("git-get-tar-commit-id: read error");
+	if (header->typeflag[0] != 'g')
+		return 1;
+	if (memcmp(content, "52 comment=", 11))
+		return 1;
+
+	n = xwrite(1, content + 11, 41);
+	if (n < 41)
+		die("git-get-tar-commit-id: write error");
+
+	return 0;
+}