diff --git a/abspath.c b/abspath.c
index d032f5dce51..1202cde23db 100644
--- a/abspath.c
+++ b/abspath.c
@@ -289,3 +289,39 @@ char *prefix_filename_except_for_dash(const char *pfx, const char *arg)
 		return xstrdup(arg);
 	return prefix_filename(pfx, arg);
 }
+
+void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
+{
+	if (!*path)
+		die("The empty string is not a valid path");
+	if (!is_absolute_path(path)) {
+		struct stat cwd_stat, pwd_stat;
+		size_t orig_len = sb->len;
+		char *cwd = xgetcwd();
+		char *pwd = getenv("PWD");
+		if (pwd && strcmp(pwd, cwd) &&
+		    !stat(cwd, &cwd_stat) &&
+		    (cwd_stat.st_dev || cwd_stat.st_ino) &&
+		    !stat(pwd, &pwd_stat) &&
+		    pwd_stat.st_dev == cwd_stat.st_dev &&
+		    pwd_stat.st_ino == cwd_stat.st_ino)
+			strbuf_addstr(sb, pwd);
+		else
+			strbuf_addstr(sb, cwd);
+		if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
+			strbuf_addch(sb, '/');
+		free(cwd);
+	}
+	strbuf_addstr(sb, path);
+}
+
+void strbuf_add_real_path(struct strbuf *sb, const char *path)
+{
+	if (sb->len) {
+		struct strbuf resolved = STRBUF_INIT;
+		strbuf_realpath(&resolved, path, 1);
+		strbuf_addbuf(sb, &resolved);
+		strbuf_release(&resolved);
+	} else
+		strbuf_realpath(sb, path, 1);
+}
diff --git a/abspath.h b/abspath.h
index 7cd3de5e9de..4653080d5e4 100644
--- a/abspath.h
+++ b/abspath.h
@@ -30,4 +30,25 @@ static inline int is_absolute_path(const char *path)
 	return is_dir_sep(path[0]) || has_dos_drive_prefix(path);
 }
 
+/**
+ * Add a path to a buffer, converting a relative path to an
+ * absolute one in the process.  Symbolic links are not
+ * resolved.
+ */
+void strbuf_add_absolute_path(struct strbuf *sb, const char *path);
+
+/**
+ * Canonize `path` (make it absolute, resolve symlinks, remove extra
+ * slashes) and append it to `sb`.  Die with an informative error
+ * message if there is a problem.
+ *
+ * The directory part of `path` (i.e., everything up to the last
+ * dir_sep) must denote a valid, existing directory, but the last
+ * component need not exist.
+ *
+ * Callers that don't mind links should use the more lightweight
+ * strbuf_add_absolute_path() instead.
+ */
+void strbuf_add_real_path(struct strbuf *sb, const char *path);
+
 #endif /* ABSPATH_H */
diff --git a/add-patch.c b/add-patch.c
index 8d770d203ff..9702c1aabdb 100644
--- a/add-patch.c
+++ b/add-patch.c
@@ -1105,10 +1105,11 @@ static int edit_hunk_manually(struct add_p_state *s, struct hunk *hunk)
 	size_t i;
 
 	strbuf_reset(&s->buf);
-	strbuf_commented_addf(&s->buf, _("Manual hunk edit mode -- see bottom for "
-				      "a quick guide.\n"));
+	strbuf_commented_addf(&s->buf, comment_line_char,
+			      _("Manual hunk edit mode -- see bottom for "
+				"a quick guide.\n"));
 	render_hunk(s, hunk, 0, 0, &s->buf);
-	strbuf_commented_addf(&s->buf,
+	strbuf_commented_addf(&s->buf, comment_line_char,
 			      _("---\n"
 				"To remove '%c' lines, make them ' ' lines "
 				"(context).\n"
@@ -1117,12 +1118,13 @@ static int edit_hunk_manually(struct add_p_state *s, struct hunk *hunk)
 			      s->mode->is_reverse ? '+' : '-',
 			      s->mode->is_reverse ? '-' : '+',
 			      comment_line_char);
-	strbuf_commented_addf(&s->buf, "%s", _(s->mode->edit_hunk_hint));
+	strbuf_commented_addf(&s->buf, comment_line_char, "%s",
+			      _(s->mode->edit_hunk_hint));
 	/*
 	 * TRANSLATORS: 'it' refers to the patch mentioned in the previous
 	 * messages.
 	 */
-	strbuf_commented_addf(&s->buf,
+	strbuf_commented_addf(&s->buf, comment_line_char,
 			      _("If it does not apply cleanly, you will be "
 				"given an opportunity to\n"
 				"edit again.  If all lines of the hunk are "
diff --git a/builtin/am.c b/builtin/am.c
index 5c83f2e003f..9ece2e30667 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -1283,7 +1283,7 @@ static int parse_mail(struct am_state *state, const char *mail)
 
 	strbuf_addstr(&msg, "\n\n");
 	strbuf_addbuf(&msg, &mi.log_message);
-	strbuf_stripspace(&msg, 0);
+	strbuf_stripspace(&msg, '\0');
 
 	assert(!state->author_name);
 	state->author_name = strbuf_detach(&author_name, NULL);
diff --git a/builtin/branch.c b/builtin/branch.c
index e6c2655af68..40a79e60f54 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -674,7 +674,7 @@ static int edit_branch_description(const char *branch_name)
 	exists = !read_branch_desc(&buf, branch_name);
 	if (!buf.len || buf.buf[buf.len-1] != '\n')
 		strbuf_addch(&buf, '\n');
-	strbuf_commented_addf(&buf,
+	strbuf_commented_addf(&buf, comment_line_char,
 		    _("Please edit the description for the branch\n"
 		      "  %s\n"
 		      "Lines starting with '%c' will be stripped.\n"),
@@ -685,7 +685,7 @@ static int edit_branch_description(const char *branch_name)
 		strbuf_release(&buf);
 		return -1;
 	}
-	strbuf_stripspace(&buf, 1);
+	strbuf_stripspace(&buf, comment_line_char);
 
 	strbuf_addf(&name, "branch.%s.description", branch_name);
 	if (buf.len || exists)
diff --git a/builtin/commit.c b/builtin/commit.c
index e67c4be2211..e002ebf070f 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -893,7 +893,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 	s->hints = 0;
 
 	if (clean_message_contents)
-		strbuf_stripspace(&sb, 0);
+		strbuf_stripspace(&sb, '\0');
 
 	if (signoff)
 		append_signoff(&sb, ignore_non_trailer(sb.buf, sb.len), 0);
diff --git a/builtin/credential-store.c b/builtin/credential-store.c
index 30c6ccf56c0..5eea5bdb584 100644
--- a/builtin/credential-store.c
+++ b/builtin/credential-store.c
@@ -74,6 +74,25 @@ static void rewrite_credential_file(const char *fn, struct credential *c,
 		die_errno("unable to write credential store");
 }
 
+static int is_rfc3986_unreserved(char ch)
+{
+	return isalnum(ch) ||
+		ch == '-' || ch == '_' || ch == '.' || ch == '~';
+}
+
+static int is_rfc3986_reserved_or_unreserved(char ch)
+{
+	if (is_rfc3986_unreserved(ch))
+		return 1;
+	switch (ch) {
+		case '!': case '*': case '\'': case '(': case ')': case ';':
+		case ':': case '@': case '&': case '=': case '+': case '$':
+		case ',': case '/': case '?': case '#': case '[': case ']':
+			return 1;
+	}
+	return 0;
+}
+
 static void store_credential_file(const char *fn, struct credential *c)
 {
 	struct strbuf buf = STRBUF_INIT;
diff --git a/builtin/merge.c b/builtin/merge.c
index 8da3e46abb0..1d14767c0c3 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -879,13 +879,15 @@ static void prepare_to_commit(struct commit_list *remoteheads)
 		strbuf_addch(&msg, '\n');
 		if (cleanup_mode == COMMIT_MSG_CLEANUP_SCISSORS) {
 			wt_status_append_cut_line(&msg);
-			strbuf_commented_addf(&msg, "\n");
+			strbuf_commented_addf(&msg, comment_line_char, "\n");
 		}
-		strbuf_commented_addf(&msg, _(merge_editor_comment));
+		strbuf_commented_addf(&msg, comment_line_char,
+				      _(merge_editor_comment));
 		if (cleanup_mode == COMMIT_MSG_CLEANUP_SCISSORS)
-			strbuf_commented_addf(&msg, _(scissors_editor_comment));
+			strbuf_commented_addf(&msg, comment_line_char,
+					      _(scissors_editor_comment));
 		else
-			strbuf_commented_addf(&msg,
+			strbuf_commented_addf(&msg, comment_line_char,
 				_(no_scissors_editor_comment), comment_line_char);
 	}
 	if (signoff)
diff --git a/builtin/notes.c b/builtin/notes.c
index 9df848d2d8c..12d966618bf 100644
--- a/builtin/notes.c
+++ b/builtin/notes.c
@@ -12,6 +12,7 @@
 #include "config.h"
 #include "builtin.h"
 #include "editor.h"
+#include "environment.h"
 #include "gettext.h"
 #include "hex.h"
 #include "notes.h"
@@ -180,7 +181,7 @@ static void write_commented_object(int fd, const struct object_id *object)
 
 	if (strbuf_read(&buf, show.out, 0) < 0)
 		die_errno(_("could not read 'show' output"));
-	strbuf_add_commented_lines(&cbuf, buf.buf, buf.len);
+	strbuf_add_commented_lines(&cbuf, buf.buf, buf.len, comment_line_char);
 	write_or_die(fd, cbuf.buf, cbuf.len);
 
 	strbuf_release(&cbuf);
@@ -208,9 +209,10 @@ static void prepare_note_data(const struct object_id *object, struct note_data *
 			copy_obj_to_fd(fd, old_note);
 
 		strbuf_addch(&buf, '\n');
-		strbuf_add_commented_lines(&buf, "\n", strlen("\n"));
-		strbuf_add_commented_lines(&buf, _(note_template), strlen(_(note_template)));
-		strbuf_add_commented_lines(&buf, "\n", strlen("\n"));
+		strbuf_add_commented_lines(&buf, "\n", strlen("\n"), comment_line_char);
+		strbuf_add_commented_lines(&buf, _(note_template), strlen(_(note_template)),
+					   comment_line_char);
+		strbuf_add_commented_lines(&buf, "\n", strlen("\n"), comment_line_char);
 		write_or_die(fd, buf.buf, buf.len);
 
 		write_commented_object(fd, object);
@@ -223,7 +225,7 @@ static void prepare_note_data(const struct object_id *object, struct note_data *
 			die(_("please supply the note contents using either -m or -F option"));
 		}
 		if (d->stripspace)
-			strbuf_stripspace(&d->buf, 1);
+			strbuf_stripspace(&d->buf, comment_line_char);
 	}
 }
 
diff --git a/builtin/rebase.c b/builtin/rebase.c
index ace1d5e8d11..b1ba9fb05dd 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -209,7 +209,7 @@ static int edit_todo_file(unsigned flags)
 	if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
 		return error_errno(_("could not read '%s'."), todo_file);
 
-	strbuf_stripspace(&todo_list.buf, 1);
+	strbuf_stripspace(&todo_list.buf, comment_line_char);
 	res = edit_todo_list(the_repository, &todo_list, &new_todo, NULL, NULL, flags);
 	if (!res && todo_list_write_to_file(the_repository, &new_todo, todo_file,
 					    NULL, NULL, -1, flags & ~(TODO_LIST_SHORTEN_IDS)))
diff --git a/builtin/stripspace.c b/builtin/stripspace.c
index 9451eb69ff4..1987752359c 100644
--- a/builtin/stripspace.c
+++ b/builtin/stripspace.c
@@ -1,6 +1,7 @@
 #include "builtin.h"
 #include "cache.h"
 #include "config.h"
+#include "environment.h"
 #include "gettext.h"
 #include "parse-options.h"
 #include "setup.h"
@@ -13,7 +14,7 @@ static void comment_lines(struct strbuf *buf)
 	size_t len;
 
 	msg = strbuf_detach(buf, &len);
-	strbuf_add_commented_lines(buf, msg, len);
+	strbuf_add_commented_lines(buf, msg, len, comment_line_char);
 	free(msg);
 }
 
@@ -58,7 +59,8 @@ int cmd_stripspace(int argc, const char **argv, const char *prefix)
 		die_errno("could not read the input");
 
 	if (mode == STRIP_DEFAULT || mode == STRIP_COMMENTS)
-		strbuf_stripspace(&buf, mode == STRIP_COMMENTS);
+		strbuf_stripspace(&buf,
+			  mode == STRIP_COMMENTS ? comment_line_char : '\0');
 	else
 		comment_lines(&buf);
 
diff --git a/builtin/tag.c b/builtin/tag.c
index 1850a6a6fdc..b79e0a88e68 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -311,9 +311,11 @@ static void create_tag(const struct object_id *object, const char *object_ref,
 			struct strbuf buf = STRBUF_INIT;
 			strbuf_addch(&buf, '\n');
 			if (opt->cleanup_mode == CLEANUP_ALL)
-				strbuf_commented_addf(&buf, _(tag_template), tag, comment_line_char);
+				strbuf_commented_addf(&buf, comment_line_char,
+				      _(tag_template), tag, comment_line_char);
 			else
-				strbuf_commented_addf(&buf, _(tag_template_nocleanup), tag, comment_line_char);
+				strbuf_commented_addf(&buf, comment_line_char,
+				      _(tag_template_nocleanup), tag, comment_line_char);
 			write_or_die(fd, buf.buf, buf.len);
 			strbuf_release(&buf);
 		}
@@ -327,7 +329,8 @@ static void create_tag(const struct object_id *object, const char *object_ref,
 	}
 
 	if (opt->cleanup_mode != CLEANUP_NONE)
-		strbuf_stripspace(buf, opt->cleanup_mode == CLEANUP_ALL);
+		strbuf_stripspace(buf,
+		  opt->cleanup_mode == CLEANUP_ALL ? comment_line_char : '\0');
 
 	if (!opt->message_given && !buf->len)
 		die(_("no tag message?"));
diff --git a/dir.h b/dir.h
index 79b85a01ee4..bb0b4fb9b60 100644
--- a/dir.h
+++ b/dir.h
@@ -6,6 +6,8 @@
 #include "statinfo.h"
 #include "strbuf.h"
 
+struct repository;
+
 /**
  * The directory listing API is used to enumerate paths in the work tree,
  * optionally taking `.git/info/exclude` and `.gitignore` files per directory
diff --git a/fmt-merge-msg.c b/fmt-merge-msg.c
index 5af0d4715ba..5d15e2387d8 100644
--- a/fmt-merge-msg.c
+++ b/fmt-merge-msg.c
@@ -508,7 +508,8 @@ static void fmt_tag_signature(struct strbuf *tagbuf,
 	strbuf_complete_line(tagbuf);
 	if (sig->len) {
 		strbuf_addch(tagbuf, '\n');
-		strbuf_add_commented_lines(tagbuf, sig->buf, sig->len);
+		strbuf_add_commented_lines(tagbuf, sig->buf, sig->len,
+					   comment_line_char);
 	}
 }
 
@@ -554,7 +555,8 @@ static void fmt_merge_msg_sigs(struct strbuf *out)
 				strbuf_addch(&tagline, '\n');
 				strbuf_add_commented_lines(&tagline,
 						origins.items[first_tag].string,
-						strlen(origins.items[first_tag].string));
+						strlen(origins.items[first_tag].string),
+						comment_line_char);
 				strbuf_insert(&tagbuf, 0, tagline.buf,
 					      tagline.len);
 				strbuf_release(&tagline);
@@ -562,7 +564,8 @@ static void fmt_merge_msg_sigs(struct strbuf *out)
 			strbuf_addch(&tagbuf, '\n');
 			strbuf_add_commented_lines(&tagbuf,
 					origins.items[i].string,
-					strlen(origins.items[i].string));
+					strlen(origins.items[i].string),
+					comment_line_char);
 			fmt_tag_signature(&tagbuf, &sig, buf, len);
 		}
 		strbuf_release(&payload);
diff --git a/gpg-interface.c b/gpg-interface.c
index 19a3471a0b5..6a3817bbca5 100644
--- a/gpg-interface.c
+++ b/gpg-interface.c
@@ -13,6 +13,7 @@
 #include "tempfile.h"
 #include "alias.h"
 #include "wrapper.h"
+#include "environment.h"
 
 static int git_gpg_config(const char *, const char *, void *);
 
@@ -586,8 +587,8 @@ static int verify_ssh_signed_buffer(struct signature_check *sigc,
 		}
 	}
 
-	strbuf_stripspace(&ssh_keygen_out, 0);
-	strbuf_stripspace(&ssh_keygen_err, 0);
+	strbuf_stripspace(&ssh_keygen_out, '\0');
+	strbuf_stripspace(&ssh_keygen_err, '\0');
 	/* Add stderr outputs to show the user actual ssh-keygen errors */
 	strbuf_add(&ssh_keygen_out, ssh_principals_err.buf, ssh_principals_err.len);
 	strbuf_add(&ssh_keygen_out, ssh_keygen_err.buf, ssh_keygen_err.len);
diff --git a/hook.c b/hook.c
index 3ca5e60895d..f6306d72b31 100644
--- a/hook.c
+++ b/hook.c
@@ -1,4 +1,5 @@
 #include "git-compat-util.h"
+#include "abspath.h"
 #include "advice.h"
 #include "gettext.h"
 #include "hook.h"
diff --git a/object-name.c b/object-name.c
index 6fc3fa595b8..34e0f567037 100644
--- a/object-name.c
+++ b/object-name.c
@@ -768,6 +768,21 @@ static void find_abbrev_len_packed(struct min_abbrev_data *mad)
 		find_abbrev_len_for_pack(p, mad);
 }
 
+void strbuf_repo_add_unique_abbrev(struct strbuf *sb, struct repository *repo,
+				   const struct object_id *oid, int abbrev_len)
+{
+	int r;
+	strbuf_grow(sb, GIT_MAX_HEXSZ + 1);
+	r = repo_find_unique_abbrev_r(repo, sb->buf + sb->len, oid, abbrev_len);
+	strbuf_setlen(sb, sb->len + r);
+}
+
+void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
+			      int abbrev_len)
+{
+	strbuf_repo_add_unique_abbrev(sb, the_repository, oid, abbrev_len);
+}
+
 int repo_find_unique_abbrev_r(struct repository *r, char *hex,
 			      const struct object_id *oid, int len)
 {
diff --git a/object-name.h b/object-name.h
index 1d63698f42b..9ae52230714 100644
--- a/object-name.h
+++ b/object-name.h
@@ -40,6 +40,15 @@ struct object_context {
 const char *repo_find_unique_abbrev(struct repository *r, const struct object_id *oid, int len);
 int repo_find_unique_abbrev_r(struct repository *r, char *hex, const struct object_id *oid, int len);
 
+/**
+ * Add the abbreviation, as generated by repo_find_unique_abbrev(), of `sha1` to
+ * the strbuf `sb`.
+ */
+void strbuf_repo_add_unique_abbrev(struct strbuf *sb, struct repository *repo,
+				   const struct object_id *oid, int abbrev_len);
+void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
+			      int abbrev_len);
+
 int repo_get_oid(struct repository *r, const char *str, struct object_id *oid);
 __attribute__((format (printf, 2, 3)))
 int get_oidf(struct object_id *oid, const char *fmt, ...);
diff --git a/path.c b/path.c
index 7c1cd8182a8..e17a2613c5f 100644
--- a/path.c
+++ b/path.c
@@ -1213,6 +1213,26 @@ int normalize_path_copy(char *dst, const char *src)
 	return normalize_path_copy_len(dst, src, NULL);
 }
 
+int strbuf_normalize_path(struct strbuf *src)
+{
+	struct strbuf dst = STRBUF_INIT;
+
+	strbuf_grow(&dst, src->len);
+	if (normalize_path_copy(dst.buf, src->buf) < 0) {
+		strbuf_release(&dst);
+		return -1;
+	}
+
+	/*
+	 * normalize_path does not tell us the new length, so we have to
+	 * compute it by looking for the new NUL it placed
+	 */
+	strbuf_setlen(&dst, strlen(dst.buf));
+	strbuf_swap(src, &dst);
+	strbuf_release(&dst);
+	return 0;
+}
+
 /*
  * path = Canonical absolute path
  * prefixes = string_list containing normalized, absolute paths without
diff --git a/path.h b/path.h
index 60e83a49a98..639372edd9e 100644
--- a/path.h
+++ b/path.h
@@ -191,6 +191,11 @@ const char *remove_leading_path(const char *in, const char *prefix);
 const char *relative_path(const char *in, const char *prefix, struct strbuf *sb);
 int normalize_path_copy_len(char *dst, const char *src, int *prefix_len);
 int normalize_path_copy(char *dst, const char *src);
+/**
+ * Normalize in-place the path contained in the strbuf. If an error occurs,
+ * the contents of "sb" are left untouched, and -1 is returned.
+ */
+int strbuf_normalize_path(struct strbuf *src);
 int longest_ancestor_length(const char *path, struct string_list *prefixes);
 char *strip_path_suffix(const char *path, const char *suffix);
 int daemon_avoid_alias(const char *path);
diff --git a/pretty.c b/pretty.c
index 0bb938021ba..78bac2d8189 100644
--- a/pretty.c
+++ b/pretty.c
@@ -18,6 +18,7 @@
 #include "gpg-interface.h"
 #include "trailer.h"
 #include "run-command.h"
+#include "object-name.h"
 
 /*
  * The limit for formatting directives, which enable the caller to append
diff --git a/rebase-interactive.c b/rebase-interactive.c
index 852a3313182..f286404d4b5 100644
--- a/rebase-interactive.c
+++ b/rebase-interactive.c
@@ -72,13 +72,14 @@ void append_todo_help(int command_count,
 
 	if (!edit_todo) {
 		strbuf_addch(buf, '\n');
-		strbuf_commented_addf(buf, Q_("Rebase %s onto %s (%d command)",
-					      "Rebase %s onto %s (%d commands)",
-					      command_count),
+		strbuf_commented_addf(buf, comment_line_char,
+				      Q_("Rebase %s onto %s (%d command)",
+					 "Rebase %s onto %s (%d commands)",
+					 command_count),
 				      shortrevisions, shortonto, command_count);
 	}
 
-	strbuf_add_commented_lines(buf, msg, strlen(msg));
+	strbuf_add_commented_lines(buf, msg, strlen(msg), comment_line_char);
 
 	if (get_missing_commit_check_level() == MISSING_COMMIT_CHECK_ERROR)
 		msg = _("\nDo not remove any line. Use 'drop' "
@@ -87,7 +88,7 @@ void append_todo_help(int command_count,
 		msg = _("\nIf you remove a line here "
 			 "THAT COMMIT WILL BE LOST.\n");
 
-	strbuf_add_commented_lines(buf, msg, strlen(msg));
+	strbuf_add_commented_lines(buf, msg, strlen(msg), comment_line_char);
 
 	if (edit_todo)
 		msg = _("\nYou are editing the todo file "
@@ -98,7 +99,7 @@ void append_todo_help(int command_count,
 		msg = _("\nHowever, if you remove everything, "
 			"the rebase will be aborted.\n\n");
 
-	strbuf_add_commented_lines(buf, msg, strlen(msg));
+	strbuf_add_commented_lines(buf, msg, strlen(msg), comment_line_char);
 }
 
 int edit_todo_list(struct repository *r, struct todo_list *todo_list,
@@ -130,7 +131,7 @@ int edit_todo_list(struct repository *r, struct todo_list *todo_list,
 	if (launch_sequence_editor(todo_file, &new_todo->buf, NULL))
 		return -2;
 
-	strbuf_stripspace(&new_todo->buf, 1);
+	strbuf_stripspace(&new_todo->buf, comment_line_char);
 	if (initial && new_todo->buf.len == 0)
 		return -3;
 
diff --git a/sequencer.c b/sequencer.c
index b553b49fbb6..c9f8b5d4ba3 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -660,11 +660,12 @@ void append_conflicts_hint(struct index_state *istate,
 	}
 
 	strbuf_addch(msgbuf, '\n');
-	strbuf_commented_addf(msgbuf, "Conflicts:\n");
+	strbuf_commented_addf(msgbuf, comment_line_char, "Conflicts:\n");
 	for (i = 0; i < istate->cache_nr;) {
 		const struct cache_entry *ce = istate->cache[i++];
 		if (ce_stage(ce)) {
-			strbuf_commented_addf(msgbuf, "\t%s\n", ce->name);
+			strbuf_commented_addf(msgbuf, comment_line_char,
+					      "\t%s\n", ce->name);
 			while (i < istate->cache_nr &&
 			       !strcmp(ce->name, istate->cache[i]->name))
 				i++;
@@ -1143,7 +1144,8 @@ void cleanup_message(struct strbuf *msgbuf,
 	    cleanup_mode == COMMIT_MSG_CLEANUP_SCISSORS)
 		strbuf_setlen(msgbuf, wt_status_locate_end(msgbuf->buf, msgbuf->len));
 	if (cleanup_mode != COMMIT_MSG_CLEANUP_NONE)
-		strbuf_stripspace(msgbuf, cleanup_mode == COMMIT_MSG_CLEANUP_ALL);
+		strbuf_stripspace(msgbuf,
+		  cleanup_mode == COMMIT_MSG_CLEANUP_ALL ? comment_line_char : '\0');
 }
 
 /*
@@ -1174,7 +1176,8 @@ int template_untouched(const struct strbuf *sb, const char *template_file,
 	if (!template_file || strbuf_read_file(&tmpl, template_file, 0) <= 0)
 		return 0;
 
-	strbuf_stripspace(&tmpl, cleanup_mode == COMMIT_MSG_CLEANUP_ALL);
+	strbuf_stripspace(&tmpl,
+	  cleanup_mode == COMMIT_MSG_CLEANUP_ALL ? comment_line_char : '\0');
 	if (!skip_prefix(sb->buf, tmpl.buf, &start))
 		start = sb->buf;
 	strbuf_release(&tmpl);
@@ -1546,7 +1549,8 @@ static int try_to_commit(struct repository *r,
 		cleanup = opts->default_msg_cleanup;
 
 	if (cleanup != COMMIT_MSG_CLEANUP_NONE)
-		strbuf_stripspace(msg, cleanup == COMMIT_MSG_CLEANUP_ALL);
+		strbuf_stripspace(msg,
+		  cleanup == COMMIT_MSG_CLEANUP_ALL ? comment_line_char : '\0');
 	if ((flags & EDIT_MSG) && message_is_empty(msg, cleanup)) {
 		res = 1; /* run 'git commit' to display error message */
 		goto out;
@@ -1840,7 +1844,7 @@ static void add_commented_lines(struct strbuf *buf, const void *str, size_t len)
 		s += count;
 		len -= count;
 	}
-	strbuf_add_commented_lines(buf, s, len);
+	strbuf_add_commented_lines(buf, s, len, comment_line_char);
 }
 
 /* Does the current fixup chain contain a squash command? */
@@ -1939,7 +1943,7 @@ static int append_squash_message(struct strbuf *buf, const char *body,
 	strbuf_addf(buf, _(nth_commit_msg_fmt),
 		    ++opts->current_fixup_count + 1);
 	strbuf_addstr(buf, "\n\n");
-	strbuf_add_commented_lines(buf, body, commented_len);
+	strbuf_add_commented_lines(buf, body, commented_len, comment_line_char);
 	/* buf->buf may be reallocated so store an offset into the buffer */
 	fixup_off = buf->len;
 	strbuf_addstr(buf, body + commented_len);
@@ -2029,7 +2033,8 @@ static int update_squash_messages(struct repository *r,
 			      _(first_commit_msg_str));
 		strbuf_addstr(&buf, "\n\n");
 		if (is_fixup_flag(command, flag))
-			strbuf_add_commented_lines(&buf, body, strlen(body));
+			strbuf_add_commented_lines(&buf, body, strlen(body),
+						   comment_line_char);
 		else
 			strbuf_addstr(&buf, body);
 
@@ -2048,7 +2053,8 @@ static int update_squash_messages(struct repository *r,
 		strbuf_addf(&buf, _(skip_nth_commit_msg_fmt),
 			    ++opts->current_fixup_count + 1);
 		strbuf_addstr(&buf, "\n\n");
-		strbuf_add_commented_lines(&buf, body, strlen(body));
+		strbuf_add_commented_lines(&buf, body, strlen(body),
+					   comment_line_char);
 	} else
 		return error(_("unknown command: %d"), command);
 	repo_unuse_commit_buffer(r, commit, message);
diff --git a/strbuf.c b/strbuf.c
index 08eec8f1d8b..b38d32325d1 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -1,12 +1,9 @@
 #include "git-compat-util.h"
-#include "abspath.h"
 #include "alloc.h"
-#include "environment.h"
 #include "gettext.h"
 #include "hex.h"
-#include "object-name.h"
-#include "refs.h"
 #include "repository.h"
+#include "strbuf.h"
 #include "string-list.h"
 #include "utf8.h"
 #include "date.h"
@@ -365,7 +362,8 @@ static void add_lines(struct strbuf *out,
 	strbuf_complete_line(out);
 }
 
-void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
+void strbuf_add_commented_lines(struct strbuf *out, const char *buf,
+				size_t size, char comment_line_char)
 {
 	static char prefix1[3];
 	static char prefix2[2];
@@ -377,7 +375,8 @@ void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size
 	add_lines(out, prefix1, prefix2, buf, size);
 }
 
-void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
+void strbuf_commented_addf(struct strbuf *sb, char comment_line_char,
+			   const char *fmt, ...)
 {
 	va_list params;
 	struct strbuf buf = STRBUF_INIT;
@@ -387,7 +386,7 @@ void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 	strbuf_vaddf(&buf, fmt, params);
 	va_end(params);
 
-	strbuf_add_commented_lines(sb, buf.buf, buf.len);
+	strbuf_add_commented_lines(sb, buf.buf, buf.len, comment_line_char);
 	if (incomplete_line)
 		sb->buf[--sb->len] = '\0';
 
@@ -811,25 +810,6 @@ void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 	}
 }
 
-int is_rfc3986_reserved_or_unreserved(char ch)
-{
-	if (is_rfc3986_unreserved(ch))
-		return 1;
-	switch (ch) {
-		case '!': case '*': case '\'': case '(': case ')': case ';':
-		case ':': case '@': case '&': case '=': case '+': case '$':
-		case ',': case '/': case '?': case '#': case '[': case ']':
-			return 1;
-	}
-	return 0;
-}
-
-int is_rfc3986_unreserved(char ch)
-{
-	return isalnum(ch) ||
-		ch == '-' || ch == '_' || ch == '.' || ch == '~';
-}
-
 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 				 char_predicate allow_unencoded_fn)
 {
@@ -900,42 +880,6 @@ void strbuf_humanise_rate(struct strbuf *buf, off_t bytes)
 	strbuf_humanise(buf, bytes, 1);
 }
 
-void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
-{
-	if (!*path)
-		die("The empty string is not a valid path");
-	if (!is_absolute_path(path)) {
-		struct stat cwd_stat, pwd_stat;
-		size_t orig_len = sb->len;
-		char *cwd = xgetcwd();
-		char *pwd = getenv("PWD");
-		if (pwd && strcmp(pwd, cwd) &&
-		    !stat(cwd, &cwd_stat) &&
-		    (cwd_stat.st_dev || cwd_stat.st_ino) &&
-		    !stat(pwd, &pwd_stat) &&
-		    pwd_stat.st_dev == cwd_stat.st_dev &&
-		    pwd_stat.st_ino == cwd_stat.st_ino)
-			strbuf_addstr(sb, pwd);
-		else
-			strbuf_addstr(sb, cwd);
-		if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
-			strbuf_addch(sb, '/');
-		free(cwd);
-	}
-	strbuf_addstr(sb, path);
-}
-
-void strbuf_add_real_path(struct strbuf *sb, const char *path)
-{
-	if (sb->len) {
-		struct strbuf resolved = STRBUF_INIT;
-		strbuf_realpath(&resolved, path, 1);
-		strbuf_addbuf(sb, &resolved);
-		strbuf_release(&resolved);
-	} else
-		strbuf_realpath(sb, path, 1);
-}
-
 int printf_ln(const char *fmt, ...)
 {
 	int ret;
@@ -1080,21 +1024,6 @@ void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 	strbuf_setlen(sb, sb->len + len);
 }
 
-void strbuf_repo_add_unique_abbrev(struct strbuf *sb, struct repository *repo,
-				   const struct object_id *oid, int abbrev_len)
-{
-	int r;
-	strbuf_grow(sb, GIT_MAX_HEXSZ + 1);
-	r = repo_find_unique_abbrev_r(repo, sb->buf + sb->len, oid, abbrev_len);
-	strbuf_setlen(sb, sb->len + r);
-}
-
-void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
-			      int abbrev_len)
-{
-	strbuf_repo_add_unique_abbrev(sb, the_repository, oid, abbrev_len);
-}
-
 /*
  * Returns the length of a line, without trailing spaces.
  *
@@ -1124,10 +1053,10 @@ static size_t cleanup(char *line, size_t len)
  *
  * If last line does not have a newline at the end, one is added.
  *
- * Enable skip_comments to skip every line starting with comment
- * character.
+ * Pass a non-NUL comment_line_char to skip every line starting
+ * with it.
  */
-void strbuf_stripspace(struct strbuf *sb, int skip_comments)
+void strbuf_stripspace(struct strbuf *sb, char comment_line_char)
 {
 	size_t empties = 0;
 	size_t i, j, len, newlen;
@@ -1140,7 +1069,8 @@ void strbuf_stripspace(struct strbuf *sb, int skip_comments)
 		eol = memchr(sb->buf + i, '\n', sb->len - i);
 		len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
 
-		if (skip_comments && len && sb->buf[i] == comment_line_char) {
+		if (comment_line_char && len &&
+		    sb->buf[i] == comment_line_char) {
 			newlen = 0;
 			continue;
 		}
@@ -1161,26 +1091,6 @@ void strbuf_stripspace(struct strbuf *sb, int skip_comments)
 	strbuf_setlen(sb, j);
 }
 
-int strbuf_normalize_path(struct strbuf *src)
-{
-	struct strbuf dst = STRBUF_INIT;
-
-	strbuf_grow(&dst, src->len);
-	if (normalize_path_copy(dst.buf, src->buf) < 0) {
-		strbuf_release(&dst);
-		return -1;
-	}
-
-	/*
-	 * normalize_path does not tell us the new length, so we have to
-	 * compute it by looking for the new NUL it placed
-	 */
-	strbuf_setlen(&dst, strlen(dst.buf));
-	strbuf_swap(src, &dst);
-	strbuf_release(&dst);
-	return 0;
-}
-
 void strbuf_strip_file_from_path(struct strbuf *sb)
 {
 	char *path_sep = find_last_dir_sep(sb->buf);
diff --git a/strbuf.h b/strbuf.h
index 3dfeadb44c2..da91c172578 100644
--- a/strbuf.h
+++ b/strbuf.h
@@ -1,6 +1,14 @@
 #ifndef STRBUF_H
 #define STRBUF_H
 
+/*
+ * NOTE FOR STRBUF DEVELOPERS
+ *
+ * strbuf is a low-level primitive; as such it should interact only
+ * with other low-level primitives. Do not introduce new functions
+ * which interact with higher-level APIs.
+ */
+
 struct string_list;
 
 /**
@@ -283,7 +291,8 @@ void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
  * by a comment character and a blank.
  */
 void strbuf_add_commented_lines(struct strbuf *out,
-				const char *buf, size_t size);
+				const char *buf, size_t size,
+				char comment_line_char);
 
 
 /**
@@ -412,8 +421,8 @@ void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
  * Add a formatted string prepended by a comment character and a
  * blank to the buffer.
  */
-__attribute__((format (printf, 2, 3)))
-void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...);
+__attribute__((format (printf, 3, 4)))
+void strbuf_commented_addf(struct strbuf *sb, char comment_line_char, const char *fmt, ...);
 
 __attribute__((format (printf,2,0)))
 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap);
@@ -527,28 +536,6 @@ int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term);
  */
 int strbuf_getcwd(struct strbuf *sb);
 
-/**
- * Add a path to a buffer, converting a relative path to an
- * absolute one in the process.  Symbolic links are not
- * resolved.
- */
-void strbuf_add_absolute_path(struct strbuf *sb, const char *path);
-
-/**
- * Canonize `path` (make it absolute, resolve symlinks, remove extra
- * slashes) and append it to `sb`.  Die with an informative error
- * message if there is a problem.
- *
- * The directory part of `path` (i.e., everything up to the last
- * dir_sep) must denote a valid, existing directory, but the last
- * component need not exist.
- *
- * Callers that don't mind links should use the more lightweight
- * strbuf_add_absolute_path() instead.
- */
-void strbuf_add_real_path(struct strbuf *sb, const char *path);
-
-
 /**
  * Normalize in-place the path contained in the strbuf. See
  * normalize_path_copy() for details. If an error occurs, the contents of "sb"
@@ -557,10 +544,11 @@ void strbuf_add_real_path(struct strbuf *sb, const char *path);
 int strbuf_normalize_path(struct strbuf *sb);
 
 /**
- * Strip whitespace from a buffer. The second parameter controls if
- * comments are considered contents to be removed or not.
+ * Strip whitespace from a buffer. If comment_line_char is non-NUL,
+ * then lines beginning with that character are considered comments,
+ * thus removed.
  */
-void strbuf_stripspace(struct strbuf *buf, int skip_comments);
+void strbuf_stripspace(struct strbuf *buf, char comment_line_char);
 
 static inline int strbuf_strip_suffix(struct strbuf *sb, const char *suffix)
 {
@@ -630,16 +618,6 @@ void strbuf_add_separated_string_list(struct strbuf *str,
  */
 void strbuf_list_free(struct strbuf **list);
 
-/**
- * Add the abbreviation, as generated by repo_find_unique_abbrev(), of `sha1` to
- * the strbuf `sb`.
- */
-struct repository;
-void strbuf_repo_add_unique_abbrev(struct strbuf *sb, struct repository *repo,
-				   const struct object_id *oid, int abbrev_len);
-void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
-			      int abbrev_len);
-
 /*
  * Remove the filename from the provided path string. If the path
  * contains a trailing separator, then the path is considered a directory
@@ -704,9 +682,6 @@ int strbuf_check_branch_ref(struct strbuf *sb, const char *name);
 
 typedef int (*char_predicate)(char ch);
 
-int is_rfc3986_unreserved(char ch);
-int is_rfc3986_reserved_or_unreserved(char ch);
-
 void strbuf_addstr_urlencode(struct strbuf *sb, const char *name,
 			     char_predicate allow_unencoded_fn);
 
diff --git a/tempfile.c b/tempfile.c
index 50c377134ce..6c88a63b422 100644
--- a/tempfile.c
+++ b/tempfile.c
@@ -43,6 +43,7 @@
  */
 
 #include "git-compat-util.h"
+#include "abspath.h"
 #include "path.h"
 #include "tempfile.h"
 #include "sigchain.h"
diff --git a/wt-status.c b/wt-status.c
index 068b76ef6d9..677465b10c1 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -1024,7 +1024,7 @@ static void wt_longstatus_print_submodule_summary(struct wt_status *s, int uncom
 	if (s->display_comment_prefix) {
 		size_t len;
 		summary_content = strbuf_detach(&summary, &len);
-		strbuf_add_commented_lines(&summary, summary_content, len);
+		strbuf_add_commented_lines(&summary, summary_content, len, comment_line_char);
 		free(summary_content);
 	}
 
@@ -1099,8 +1099,8 @@ void wt_status_append_cut_line(struct strbuf *buf)
 {
 	const char *explanation = _("Do not modify or remove the line above.\nEverything below it will be ignored.");
 
-	strbuf_commented_addf(buf, "%s", cut_line);
-	strbuf_add_commented_lines(buf, explanation, strlen(explanation));
+	strbuf_commented_addf(buf, comment_line_char, "%s", cut_line);
+	strbuf_add_commented_lines(buf, explanation, strlen(explanation), comment_line_char);
 }
 
 void wt_status_add_cut_line(FILE *fp)