use write_str_in_full helper to avoid literal string lengths

In 2d14d65 (Use a clearer style to issue commands to remote helpers,
2009-09-03) I happened to notice two changes like this:

-	write_in_full(helper->in, "list\n", 5);
+
+	strbuf_addstr(&buf, "list\n");
+	write_in_full(helper->in, buf.buf, buf.len);
+	strbuf_reset(&buf);

IMHO, it would be better to define a new function,

    static inline ssize_t write_str_in_full(int fd, const char *str)
    {
           return write_in_full(fd, str, strlen(str));
    }

and then use it like this:

-       strbuf_addstr(&buf, "list\n");
-       write_in_full(helper->in, buf.buf, buf.len);
-       strbuf_reset(&buf);
+       write_str_in_full(helper->in, "list\n");

Thus not requiring the added allocation, and still avoiding
the maintenance risk of literal string lengths.
These days, compilers are good enough that strlen("literal")
imposes no run-time cost.

Transformed via this:

    perl -pi -e \
        's/write_in_full\((.*?), (".*?"), \d+\)/write_str_in_full($1, $2)/'\
      $(git grep -l 'write_in_full.*"')

Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-fetch.c

@@ -454,7 +454,7 @@ static int quickfetch(struct ref *ref_map)
 
 	for (ref = ref_map; ref; ref = ref->next) {
 		if (write_in_full(revlist.in, sha1_to_hex(ref->old_sha1), 40) < 0 ||
-		    write_in_full(revlist.in, "\n", 1) < 0) {
+		    write_str_in_full(revlist.in, "\n") < 0) {
 			if (errno != EPIPE && errno != EINVAL)
 				error("failed write to rev-list: %s", strerror(errno));
 			err = -1;

builtin-reflog.c

@@ -362,7 +362,7 @@ static int expire_reflog(const char *ref, const unsigned char *sha1, int unused,
 		} else if (cmd->updateref &&
 			(write_in_full(lock->lock_fd,
 				sha1_to_hex(cb.last_kept_sha1), 40) != 40 ||
-			 write_in_full(lock->lock_fd, "\n", 1) != 1 ||
+			 write_str_in_full(lock->lock_fd, "\n") != 1 ||
 			 close_ref(lock) < 0)) {
 			status |= error("Couldn't write %s",
 				lock->lk->filename);

cache.h

@@ -923,13 +923,18 @@ extern const char *git_mailmap_file;
 extern void maybe_flush_or_die(FILE *, const char *);
 extern int copy_fd(int ifd, int ofd);
 extern int copy_file(const char *dst, const char *src, int mode);
-extern ssize_t read_in_full(int fd, void *buf, size_t count);
-extern ssize_t write_in_full(int fd, const void *buf, size_t count);
 extern void write_or_die(int fd, const void *buf, size_t count);
 extern int write_or_whine(int fd, const void *buf, size_t count, const char *msg);
 extern int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg);
 extern void fsync_or_die(int fd, const char *);
 
+extern ssize_t read_in_full(int fd, void *buf, size_t count);
+extern ssize_t write_in_full(int fd, const void *buf, size_t count);
+static inline ssize_t write_str_in_full(int fd, const char *str)
+{
+	return write_in_full(fd, str, strlen(str));
+}
+
 /* pager.c */
 extern void setup_pager(void);
 extern const char *pager_program;

commit.c

@@ -212,7 +212,7 @@ int write_shallow_commits(int fd, int use_pack_protocol)
 			else {
 				if (write_in_full(fd, hex,  40) != 40)
 					break;
-				if (write_in_full(fd, "\n", 1) != 1)
+				if (write_str_in_full(fd, "\n") != 1)
 					break;
 			}
 		}

config.c

@@ -1116,7 +1116,7 @@ int git_config_set_multivar(const char *key, const char *value,
 				    copy_end - copy_begin)
 					goto write_err_out;
 				if (new_line &&
-				    write_in_full(fd, "\n", 1) != 1)
+				    write_str_in_full(fd, "\n") != 1)
 					goto write_err_out;
 			}
 			copy_begin = store.offset[i];

rerere.c

@@ -61,7 +61,7 @@ static int write_rr(struct string_list *rr, int out_fd)
 		path = rr->items[i].string;
 		length = strlen(path) + 1;
 		if (write_in_full(out_fd, rr->items[i].util, 40) != 40 ||
-		    write_in_full(out_fd, "\t", 1) != 1 ||
+		    write_str_in_full(out_fd, "\t") != 1 ||
 		    write_in_full(out_fd, path, length) != length)
 			die("unable to write rerere record");
 	}

upload-pack.c

@@ -553,7 +553,7 @@ static void receive_needs(void)
 
 	shallow_nr = 0;
 	if (debug_fd)
-		write_in_full(debug_fd, "#S\n", 3);
+		write_str_in_full(debug_fd, "#S\n");
 	for (;;) {
 		struct object *o;
 		unsigned char sha1_buf[20];
@@ -619,7 +619,7 @@ static void receive_needs(void)
 		}
 	}
 	if (debug_fd)
-		write_in_full(debug_fd, "#E\n", 3);
+		write_str_in_full(debug_fd, "#E\n");
 
 	if (!use_sideband && daemon_mode)
 		no_progress = 1;