Remove readline dep and use native prompt

- `nnn` is all about navigational convenience so the user doesn't have to type
- the binary size increases due to readline linkage
- alternative workflow: ^G, cd, `nnn`
- readline required using the prompt and the history would stay after quit

4 files changed, 7 insertions, 96 deletions

diff --git a/Makefile b/Makefile
index 4dd3cc1..598fae2 100644
--- a/Makefile
+++ b/Makefile
@@ -8,7 +8,6 @@ INSTALL ?= install
 
 CFLAGS ?= -O3
 CFLAGS += -Wall -Wextra -Wno-unused-parameter
-LDLIBS = -lreadline
 
 ifeq ($(shell $(PKG_CONFIG) ncursesw && echo 1),1)
 	CFLAGS += $(shell $(PKG_CONFIG) --cflags ncursesw)
diff --git a/README.md b/README.md
index afee81e..1a6214f 100644
--- a/README.md
+++ b/README.md
@@ -65,7 +65,6 @@ Have fun with it! Missing a feature? Want to contribute? Head to the rolling [To
     - [sample scripts](#sample-scripts)
   - [change dir color](#change-dir-color)
   - [file copy, move, delete](#file-copy-move-delete)
-  - [boost chdir prompt](#boost-chdir-prompt)
   - [work faster at rename prompt](#work-faster-at-rename-prompt)
   - [set idle timeout](#set-idle-timeout)
   - [show hot plugged drives](#show-hot-plugged-drives)
@@ -137,7 +136,7 @@ Intrigued? Find out [HOW](https://github.com/jarun/nnn/wiki/performance-factors)
 
 #### Dependencies
 
-`nnn` needs libreadline, libncursesw (on Linux or ncurses on OS X) and standard libc.
+`nnn` needs libncursesw (on Linux or ncurses on OS X) and standard libc.
 
 #### From a package manager
 
@@ -164,7 +163,7 @@ Packages for Arch Linux, CentOS, Debian, Fedora and Ubuntu are available with th
 
 To cook yourself, download the [latest stable release](https://github.com/jarun/nnn/releases/latest) or clone this repository (*risky*). Then install the dependencies and compile (e.g. on Ubuntu 16.04):
 
-    $ sudo apt-get install libncursesw5-dev libreadline6-dev
+    $ sudo apt-get install libncursesw5-dev
     $ make
     $ sudo make install
 
@@ -480,10 +479,6 @@ Any other value disables colored directories.
 
 In addition, `nnn` integrates with vidir. vidir supports batch file move and delete.
 
-#### boost chdir prompt
-
-`nnn` uses libreadline for the chdir prompt input. So all the fantastic features of readline (e.g. case insensitive tab completion, history, reverse-i-search) are available to you based on your readline [configuration](https://wiki.archlinux.org/index.php/Readline).
-
 #### work faster at rename prompt
 
 The rename prompt supports some bash-like command-line shortcuts - <kbd>^A</kbd>, <kbd>^E</kbd>, <kbd>^U</kbd>. <kbd>^L</kbd> clears the name.
diff --git a/nnn.c b/nnn.c
index 929555d..3e13835 100644
--- a/nnn.c
+++ b/nnn.c
@@ -73,8 +73,6 @@
 #include <string.h>
 #include <time.h>
 #include <unistd.h>
-#include <readline/history.h>
-#include <readline/readline.h>
 #ifndef __USE_XOPEN_EXTENDED
 #define __USE_XOPEN_EXTENDED 1
 #endif
@@ -849,25 +847,6 @@ xchartohex(char c)
 	return c;
 }
 
-/* Trim all whitespace from both ends, / from end */
-static char *
-strstrip(char *s)
-{
-	if (!s || !*s)
-		return s;
-
-	size_t len = strlen(s) - 1;
-
-	while (len != 0 && (isspace(s[len]) || s[len] == '/'))
-		--len;
-	s[len + 1] = '\0';
-
-	while (*s && isspace(*s))
-		++s;
-
-	return s;
-}
-
 static char *
 getmime(const char *file)
 {
@@ -2625,44 +2604,11 @@ nochange:
 			break;
 		case SEL_CD:
 		{
-			char *input;
-			int truecd;
-
-			/* Save the program start dir */
-			tmp = getcwd(newpath, PATH_MAX);
-			if (tmp == NULL) {
-				printwarn();
-				goto nochange;
-			}
-
-			/* Switch to current path for readline(3) */
-			if (chdir(path) == -1) {
-				printwarn();
-				goto nochange;
-			}
+			int truecd = 0;
 
-			exitcurses();
-			tmp = readline("cd: ");
-			refresh();
-
-			/* Change back to program start dir */
-			if (chdir(newpath) == -1)
-				printwarn();
-
-			if (tmp[0] == '\0')
-				break;
-
-			/* Add to readline(3) history */
-			add_history(tmp);
-
-			input = tmp;
-			tmp = strstrip(tmp);
-			if (tmp[0] == '\0') {
-				free(input);
+			tmp = xreadline(NULL, "cd: ");
+			if (tmp == NULL || tmp[0] == '\0')
 				break;
-			}
-
-			truecd = 0;
 
 			if (tmp[0] == '~') {
 				/* Expand ~ to HOME absolute path */
@@ -2671,30 +2617,23 @@ nochange:
 				if (home)
 					snprintf(newpath, PATH_MAX, "%s%s", home, tmp + 1);
 				else {
-					free(input);
 					printmsg(messages[STR_NOHOME_ID]);
 					goto nochange;
 				}
 			} else if (tmp[0] == '-' && tmp[1] == '\0') {
-				if (lastdir[0] == '\0') {
-					free(input);
+				if (lastdir[0] == '\0')
 					break;
-				}
 
 				/* Switch to last visited dir */
 				xstrlcpy(newpath, lastdir, PATH_MAX);
 				truecd = 1;
 			} else if ((r = all_dots(tmp))) {
-				if (r == 1) {
+				if (r == 1)
 					/* Always in the current dir */
-					free(input);
 					break;
-				}
 
 				/* Show a message if already at / */
 				if (istopdir(path)) {
-					free(input);
-
 					/* Continue in navigate-as-you-type mode, if enabled */
 					if (cfg.filtermode)
 						presel = FILTER;
@@ -2716,7 +2655,6 @@ nochange:
 					dir = xdirname(dir);
 					if (access(dir, R_OK) == -1) {
 						printwarn();
-						free(input);
 						goto nochange;
 					}
 				}
@@ -2735,8 +2673,6 @@ nochange:
 			} else
 				mkpath(path, tmp, newpath, PATH_MAX);
 
-			free(input);
-
 			if (!xdiraccess(newpath))
 				goto nochange;
 
diff --git a/packagecore.yaml b/packagecore.yaml
index dec05a5..7ebf84a 100644
--- a/packagecore.yaml
+++ b/packagecore.yaml
@@ -14,17 +14,14 @@ packages:
       - pkg-config
     deps:
       - ncurses
-      - readline
   centos7.2:
     builddeps:
       - make
       - gcc
       - pkgconfig
       - ncurses-devel
-      - readline-devel
     deps:
       - ncurses
-      - readline
     commands:
       pre:
         - yum install epel-release
@@ -34,10 +31,8 @@ packages:
       - gcc
       - pkgconfig
       - ncurses-devel
-      - readline-devel
     deps:
       - ncurses
-      - readline
     commands:
       pre:
         - yum install epel-release
@@ -47,67 +42,53 @@ packages:
       - gcc
       - pkg-config
       - libncursesw5-dev
-      - libreadline-dev
     deps:
       - libncursesw5
-      - readline-common
   fedora25:
     builddeps:
       - make
       - gcc
       - pkgconfig
       - ncurses-devel
-      - readline-devel
     deps:
       - ncurses
-      - readline
   fedora26:
     builddeps:
       - make
       - gcc
       - pkg-config
       - ncurses-devel
-      - readline-devel
     deps:
       - ncurses
-      - readline
   fedora27:
     builddeps:
       - make
       - gcc
       - pkg-config
       - ncurses-devel
-      - readline-devel
     deps:
       - ncurses
-      - readline
 #  opensuse42.3:
 #    builddeps:
 #      - make
 #      - gcc
 #      - pkg-config
 #      - ncurses-devel
-#      - readline-devel
 #    deps:
 #      - ncurses
-#      - readline
   ubuntu16.04:
     builddeps:
       - make
       - gcc
       - pkg-config
       - libncursesw5-dev
-      - libreadline6-dev
     deps:
       - libncursesw5
-      - libreadline6
   ubuntu18.04:
     builddeps:
       - make
       - gcc
       - pkg-config
       - libncursesw5-dev
-      - libreadline-dev
     deps:
       - libncursesw5
-      - libreadline7