pack-objects.c: fix some global variable abuse and memory leaks

To keep things well layered, sha1close() now returns the file descriptor
when it doesn't close the file.

An ugly cast was added to the return of write_idx_file() to avoid a
warning.  A proper fix will come separately.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

builtin-pack-objects.c

@@ -65,8 +65,6 @@ static int no_reuse_delta, no_reuse_object, keep_unreachable;
 static int local;
 static int incremental;
 static int allow_ofs_delta;
-static const char *pack_tmp_name, *idx_tmp_name;
-static char tmpname[PATH_MAX];
 static const char *base_name;
 static int progress = 1;
 static int window = 10;
@@ -587,12 +585,6 @@ static off_t write_one(struct sha1file *f,
 	return offset + size;
 }
 
-static int open_object_dir_tmp(const char *path)
-{
-    snprintf(tmpname, sizeof(tmpname), "%s/%s", get_object_directory(), path);
-    return xmkstemp(tmpname);
-}
-
 /* forward declaration for write_pack_file */
 static int adjust_perm(const char *path, mode_t mode);
 
@@ -611,11 +603,16 @@ static void write_pack_file(void)
 
 	do {
 		unsigned char sha1[20];
+		char *pack_tmp_name = NULL;
 
 		if (pack_to_stdout) {
 			f = sha1fd(1, "<stdout>");
 		} else {
-			int fd = open_object_dir_tmp("tmp_pack_XXXXXX");
+			char tmpname[PATH_MAX];
+			int fd;
+			snprintf(tmpname, sizeof(tmpname),
+				 "%s/tmp_pack_XXXXXX", get_object_directory());
+			fd = xmkstemp(tmpname);
 			pack_tmp_name = xstrdup(tmpname);
 			f = sha1fd(fd, pack_tmp_name);
 		}
@@ -643,19 +640,21 @@ static void write_pack_file(void)
 		if (pack_to_stdout || nr_written == nr_remaining) {
 			sha1close(f, sha1, 1);
 		} else {
-			sha1close(f, sha1, 0);
-			fixup_pack_header_footer(f->fd, sha1, pack_tmp_name, nr_written);
-			close(f->fd);
+			int fd = sha1close(f, NULL, 0);
+			fixup_pack_header_footer(fd, sha1, pack_tmp_name, nr_written);
+			close(fd);
 		}
 
 		if (!pack_to_stdout) {
 			mode_t mode = umask(0);
+			char *idx_tmp_name, tmpname[PATH_MAX];
 
 			umask(mode);
 			mode = 0444 & ~mode;
 
-			idx_tmp_name = write_idx_file(NULL,
-				(struct pack_idx_entry **) written_list, nr_written, sha1);
+			idx_tmp_name = (char *) write_idx_file(NULL,
+					(struct pack_idx_entry **) written_list,
+					nr_written, sha1);
 			snprintf(tmpname, sizeof(tmpname), "%s-%s.pack",
 				 base_name, sha1_to_hex(sha1));
 			if (adjust_perm(pack_tmp_name, mode))
@@ -672,6 +671,8 @@ static void write_pack_file(void)
 			if (rename(idx_tmp_name, tmpname))
 				die("unable to rename temporary index file: %s",
 				    strerror(errno));
+			free(idx_tmp_name);
+			free(pack_tmp_name);
 			puts(sha1_to_hex(sha1));
 		}
 

csum-file.c

@@ -31,22 +31,27 @@ static void sha1flush(struct sha1file *f, unsigned int count)
 
 int sha1close(struct sha1file *f, unsigned char *result, int final)
 {
+	int fd;
 	unsigned offset = f->offset;
 	if (offset) {
 		SHA1_Update(&f->ctx, f->buffer, offset);
 		sha1flush(f, offset);
 		f->offset = 0;
 	}
-	if (!final)
-		return 0;	/* only want to flush (no checksum write, no close) */
-	SHA1_Final(f->buffer, &f->ctx);
-	if (result)
-		hashcpy(result, f->buffer);
-	sha1flush(f, 20);
-	if (close(f->fd))
-		die("%s: sha1 file error on close (%s)", f->name, strerror(errno));
+	if (final) {
+		/* write checksum and close fd */
+		SHA1_Final(f->buffer, &f->ctx);
+		if (result)
+			hashcpy(result, f->buffer);
+		sha1flush(f, 20);
+		if (close(f->fd))
+			die("%s: sha1 file error on close (%s)",
+			    f->name, strerror(errno));
+		fd = 0;
+	} else
+		fd = f->fd;
 	free(f);
-	return 0;
+	return fd;
 }
 
 int sha1write(struct sha1file *f, void *buf, unsigned int count)