From 89224cfa980f4e3470e7e52decf5f9f19831dba6 Mon Sep 17 00:00:00 2001
From: Arun Prakash Jana <engineerarun@gmail.com>
Date: Thu, 20 Apr 2017 19:45:52 +0530
Subject: [PATCH] Use readline() at chdir prompt

With the features the readline library provides it would be too naive to ignore.
We break out of the curses mode into the prompt and get back in.
This change introduces dependency on libncurses.
---
 Makefile         |  5 ++--
 Makefile.generic |  5 ++--
 README.md        |  2 +-
 nnn.c            | 78 +++++++++++++++++++++++++++++++++++++++++++-----
 4 files changed, 78 insertions(+), 12 deletions(-)

diff --git a/Makefile b/Makefile
index c07e9501..bb450f91 100644
--- a/Makefile
+++ b/Makefile
@@ -4,10 +4,11 @@ PREFIX = /usr/local
 MANPREFIX = $(PREFIX)/share/man
 
 CFLAGS += -O3 -march=native -Wall -Wextra -Wno-unused-parameter
+LDLIBS = -lreadline
 ifeq ($(shell uname), Darwin)
-  LDLIBS = -lncurses
+  LDLIBS += -lncurses
 else
-  LDLIBS = -lncursesw
+  LDLIBS += -lncursesw
 endif
 
 DISTFILES = nnn.c config.def.h nnn.1 Makefile README.md LICENSE
diff --git a/Makefile.generic b/Makefile.generic
index f96cecfc..075ba0ce 100644
--- a/Makefile.generic
+++ b/Makefile.generic
@@ -4,10 +4,11 @@ PREFIX = /usr/local
 MANPREFIX = $(PREFIX)/share/man
 
 CFLAGS += -O2 -Wall -Wextra -Wno-unused-parameter
+LDLIBS = -lreadline
 ifeq ($(shell uname), Darwin)
-  LDLIBS = -lncurses
+  LDLIBS += -lncurses
 else
-  LDLIBS = -lncursesw
+  LDLIBS += -lncursesw
 endif
 
 DISTFILES = nnn.c config.def.h nnn.1 Makefile README.md LICENSE
diff --git a/README.md b/README.md
index f471d0fd..5c1edf9d 100644
--- a/README.md
+++ b/README.md
@@ -141,7 +141,7 @@ nnn vs. ranger memory usage while viewing a directory with 10,178 files, sorted
 
 ### Installation
 
-nnn needs libncursesw on Linux (or ncurses on OS X) and standard libc.
+nnn needs libreadline and libncursesw (on Linux or ncurses on OS X) and standard libc.
 
 - If you are using **Homebrew**, run:
 
diff --git a/nnn.c b/nnn.c
index 75137051..85bbdf51 100644
--- a/nnn.c
+++ b/nnn.c
@@ -1,26 +1,28 @@
 /* See LICENSE file for copyright and license details. */
+#include <readline/readline.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <sys/statvfs.h>
 #include <sys/resource.h>
 
+#include <ctype.h>
 #include <curses.h>
 #include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <grp.h>
 #include <limits.h>
 #include <locale.h>
+#include <pwd.h>
 #include <regex.h>
 #include <signal.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
 #include <time.h>
-#include <pwd.h>
-#include <grp.h>
+#include <unistd.h>
 
 #define __USE_XOPEN_EXTENDED
 #include <ftw.h>
@@ -118,6 +120,13 @@ typedef struct entry {
 
 typedef unsigned long ulong;
 
+/* Externs */
+#ifdef __APPLE__
+extern int add_history(const char *);
+#else
+extern void add_history(const char *string);
+#endif
+
 /* Global context */
 static struct entry *dents;
 static int ndents, cur;
@@ -375,6 +384,28 @@ xstricmp(const char *s1, const char *s2)
 	return (int) (TOUPPER(*s1) - TOUPPER(*s2));
 }
 
+static char *
+strstrip(char *s)
+{
+	size_t size;
+	char *end;
+
+	size = strlen(s);
+
+	if (!size)
+		return s;
+
+	end = s + size - 1;
+	while (end >= s && isspace(*end))
+		end--;
+	*(end + 1) = '\0';
+
+	while (*s && isspace(*s))
+		s++;
+
+	return s;
+}
+
 static char *
 openwith(char *file)
 {
@@ -1420,14 +1451,39 @@ nochange:
 			cur = ndents - 1;
 			break;
 		case SEL_CD:
+		{
 			/* Read target dir */
-			printprompt("chdir: ");
-			tmp = readln();
+			char cwd[PATH_MAX];
+			tmp = getcwd(cwd, PATH_MAX);
 			if (tmp == NULL) {
-				clearprompt();
+				printwarn();
 				goto nochange;
 			}
 
+			if (chdir(path) == -1) {
+				printwarn();
+				goto nochange;
+			}
+
+			exitcurses();
+			char *tmp = readline("chdir: ");
+			initcurses();
+			tmp = tmp[0] ? tmp : NULL;
+			if (chdir(cwd) == -1)
+				printwarn();
+
+			if (tmp == NULL) {
+				/* Save current */
+				if (ndents > 0)
+					mkpath(path, dents[cur].name, oldpath, sizeof(oldpath));
+
+				goto begin;
+			} else
+				add_history(tmp);
+
+			char *input = tmp;
+			tmp = strstrip(tmp);
+
 			if (tmp[0] == '~') {
 				char *home = getenv("HOME");
 				if (home)
@@ -1441,8 +1497,13 @@ nochange:
 				mkpath(path, tmp, newpath, sizeof(newpath));
 
 			if (canopendir(newpath) == 0) {
+				/* Save current */
+				if (ndents > 0)
+					mkpath(path, dents[cur].name, oldpath, sizeof(oldpath));
+
 				printwarn();
-				goto nochange;
+				free(input);
+				goto begin;
 			}
 
 			/* Save last working directory */
@@ -1452,7 +1513,10 @@ nochange:
 			/* Reset filter */
 			xstrlcpy(fltr, ifilter, sizeof(fltr));
 			DPRINTF_S(path);
+			oldpath[0] = '\0';
+			free(input);
 			goto begin;
+		}
 		case SEL_CDHOME:
 			tmp = getenv("HOME");
 			if (tmp == NULL) {