updated and fixed linenoise

history now gets read from file
started to document the protocol of biruda

6 files changed, 460 insertions, 171 deletions

diff --git a/PROTOCOL b/PROTOCOL
new file mode 100644
index 0000000..0b17c3c
--- /dev/null
+++ b/PROTOCOL
@@ -0,0 +1,41 @@
+Messages are sent over nanomsg.
+
+Message format is JSON.
+
+All messages have one string key 'op', a string key 'role' and a
+unique name field, currently 'host'.
+
+'op' can be:
+- 'discover'
+- 'register'
+
+'role' can only be:
+- 'master'
+- 'coordinator'
+- 'worker'
+
+'host' is the FQDN or hostname of a coordinator (depends on the network
+setup).
+
+Operations:
+
+Discovery:
+
+Master sends:
+
+{ "op": "discover" }
+
+Coordinators answer with:
+
+All coordinators send:
+
+{ "op": "register", "role": "coordinator", "host": "server1", 
+  "cpus": 2, "os": "cpe:\/o:arch:arch:rolling", "arch": "x86_64" }
+
+The coordinator sends its own configuration to the master.
+
+On receiving a 'register' operation the master must handle accordingly,
+usually adding the coordinator as known and alive and provide new
+platforms and architectures to run workers on. Also currently scheduled
+jobs must be examined.
+
diff --git a/TODOS b/TODOS
index b70ccc5..2ee7d8c 100644
--- a/TODOS
+++ b/TODOS
@@ -5,3 +5,8 @@
 - links
 http://blog.borovsak.si/2009/07/spawning-processes-using-glib.html
 http://www.codeguru.com/cpp/misc/misc/system/article.php/c8973/Determine-Windows-Version-and-Edition.htm
+
+- surveyor -> bus, maybe also Windows blocking problem disappears
+  - every member of the net is allowed to receive data and to send
+    answers or to request or inform about something.
+    
diff --git a/src/biruda.c b/src/biruda.c
index 6bbcafe..3543d86 100644
--- a/src/biruda.c
+++ b/src/biruda.c
@@ -215,10 +215,10 @@ static void terminate_foreground_func( int sig )
 
 #ifndef _WIN32
 
-#define HISTORY_FILE ".biruda.history"
+#define HISTORY_FILE ".biruda_history"
 
 static char *commands[] = {
-	"help", "quit", NULL
+	"help", "quit", "status", NULL
 };
 
 static void completion_func( const char *buf, linenoiseCompletions *lc )
@@ -240,22 +240,33 @@ static void print_help( )
 	puts( "\n"
 		"   help - show this help page\n"
 		"   quit - quit the client\n"
+		"   status - status of the biruda network\n"
 	);
 }
 
-static int start_interactive( )
+static void print_status( )
+{
+	puts( "\nStatus\n" );
+}
+
+static void print_error( const char *error, bool colors )
+{
+	if( colors ) {
+		printf( "%c[9%dmERROR: %s%c[0m\n", 27, 1, error, 27 );
+	} else {
+		puts( error );
+	}
+}
+
+static int start_interactive( bool colors )
 {
 	char history_filename[1024];
 
 	char *home = getenv( "HOME" );
 	if( home != NULL ) {
 		snprintf( history_filename, sizeof( history_filename ), "%s/%s", home, HISTORY_FILE );
-		FILE *history_file = fopen( history_filename, "w+" );
-		if( history_file != NULL ) {
-			fclose( history_file );
-			linenoiseHistoryLoad( HISTORY_FILE );
-			linenoiseSetCompletionCallback( completion_func );
-		}
+		linenoiseHistoryLoad( history_filename );
+		linenoiseSetCompletionCallback( completion_func );
 	}
 	
 	char *context = "biruda";
@@ -279,8 +290,12 @@ static int start_interactive( )
 		if( strncasecmp( line, "quit", 4 ) == 0 ) {
 			linenoiseHistorySave( history_filename );
 			return EXIT_SUCCESS;
-		} else if( strncasecmp( line, "help", 4 ) == 0 ){
+		} else if( strncasecmp( line, "help", 4 ) == 0 ) {
 			print_help( );
+		} else if( strncasecmp( line, "status", 6 ) == 0 ) {
+			print_status( );
+		} else {
+			print_error( "Bad command.", colors );
 		}
 	}
 
@@ -318,7 +333,7 @@ int main( int argc, char *argv[] )
 	}
 
 	if( args_info.cli_given ) {
-		return start_interactive( );
+		return start_interactive( !args_info.no_colors_given );
 	}
 
 	unsigned int has_master = cfg_size( cfg, "master" );
diff --git a/src/biruda.ggo b/src/biruda.ggo
index b6758fd..c204713 100644
--- a/src/biruda.ggo
+++ b/src/biruda.ggo
@@ -24,6 +24,10 @@ section "Main Options"
 	option "cli" i
 		"start in command line interface (CLI), interactive mode"
 		optional
+	
+	option "no-colors" -
+		"disable colors in CLI mode"
+		optional
 
 section "Unix Daemon"
 
diff --git a/src/linenoise.c b/src/linenoise.c
index 42b9382..e88fa4a 100644
--- a/src/linenoise.c
+++ b/src/linenoise.c
@@ -2,7 +2,7 @@
  * line editing lib needs to be 20,000 lines of C code.
  *
  * You can find the latest source code at:
- * 
+ *
  *   http://github.com/antirez/linenoise
  *
  * Does a number of crazy assumptions that happen to be true in 99.9999% of
@@ -10,22 +10,22 @@
  *
  * ------------------------------------------------------------------------
  *
- * Copyright (c) 2010-2013, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2014, Salvatore Sanfilippo <antirez at gmail dot com>
  * Copyright (c) 2010-2013, Pieter Noordhuis <pcnoordhuis at gmail dot com>
  *
  * All rights reserved.
- * 
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
- * 
+ *
  *  *  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  *
  *  *  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
  *     documentation and/or other materials provided with the distribution.
- * 
+ *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
@@ -37,7 +37,7 @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- * 
+ *
  * ------------------------------------------------------------------------
  *
  * References:
@@ -56,10 +56,6 @@
  * flickering effect with some slow terminal, but the lesser sequences
  * the more compatible.
  *
- * CHA (Cursor Horizontal Absolute)
- *    Sequence: ESC [ n G
- *    Effect: moves cursor to column n
- *
  * EL (Erase Line)
  *    Sequence: ESC [ n K
  *    Effect: if n is 0 or missing, clear from cursor to end of line
@@ -68,7 +64,19 @@
  *
  * CUF (CUrsor Forward)
  *    Sequence: ESC [ n C
- *    Effect: moves cursor forward of n chars
+ *    Effect: moves cursor forward n chars
+ *
+ * CUB (CUrsor Backward)
+ *    Sequence: ESC [ n D
+ *    Effect: moves cursor backward n chars
+ *
+ * The following is used to get the terminal width if getting
+ * the width with the TIOCGWINSZ ioctl fails
+ *
+ * DSR (Device Status Report)
+ *    Sequence: ESC [ 6 n
+ *    Effect: reports the current cusor position as ESC [ n ; m R
+ *            where n is the row and m is the column
  *
  * When multi line mode is enabled, we also use an additional escape
  * sequence. However multi line editing is disabled by default.
@@ -81,17 +89,18 @@
  *    Sequence: ESC [ n B
  *    Effect: moves cursor down of n chars.
  *
- * The following are used to clear the screen: ESC [ H ESC [ 2 J
- * This is actually composed of two sequences:
+ * When linenoiseClearScreen() is called, two additional escape sequences
+ * are used in order to clear the screen and position the cursor at home
+ * position.
  *
- * cursorhome
+ * CUP (Cursor position)
  *    Sequence: ESC [ H
  *    Effect: moves the cursor to upper left corner
  *
- * ED2 (Clear entire screen)
+ * ED (Erase display)
  *    Sequence: ESC [ 2 J
  *    Effect: clear the whole screen
- * 
+ *
  */
 
 #include <termios.h>
@@ -102,6 +111,7 @@
 #include <string.h>
 #include <strings.h>
 #include <stdlib.h>
+#include <ctype.h>
 #include <sys/types.h>
 #include <sys/ioctl.h>
 #include <unistd.h>
@@ -109,7 +119,7 @@
 
 #define LINENOISE_DEFAULT_HISTORY_MAX_LEN 100
 #define LINENOISE_MAX_LINE 4096
-static char *unsupported_term[] = {"dumb","cons25",NULL};
+static char *unsupported_term[] = {"dumb","cons25","emacs",NULL};
 static linenoiseCompletionCallback *completionCallback = NULL;
 
 static struct termios orig_termios; /* In order to restore at exit.*/
@@ -118,13 +128,14 @@ static int mlmode = 0;  /* Multi line mode. Default is single line. */
 static int atexit_registered = 0; /* Register atexit just 1 time. */
 static int history_max_len = LINENOISE_DEFAULT_HISTORY_MAX_LEN;
 static int history_len = 0;
-char **history = NULL;
+static char **history = NULL;
 
 /* The linenoiseState structure represents the state during line editing.
  * We pass this state to functions implementing specific editing
  * functionalities. */
 struct linenoiseState {
-    int fd;             /* Terminal file descriptor. */
+    int ifd;            /* Terminal stdin file descriptor. */
+    int ofd;            /* Terminal stdout file descriptor. */
     char *buf;          /* Edited line buffer. */
     size_t buflen;      /* Edited line buffer size. */
     const char *prompt; /* Prompt to display. */
@@ -137,16 +148,52 @@ struct linenoiseState {
     int history_index;  /* The history index we are currently editing. */
 };
 
+enum KEY_ACTION{
+	KEY_NULL = 0,	    /* NULL */
+	CTRL_A = 1,         /* Ctrl+a */
+	CTRL_B = 2,         /* Ctrl-b */
+	CTRL_C = 3,         /* Ctrl-c */
+	CTRL_D = 4,         /* Ctrl-d */
+	CTRL_E = 5,         /* Ctrl-e */
+	CTRL_F = 6,         /* Ctrl-f */
+	CTRL_H = 8,         /* Ctrl-h */
+	TAB = 9,            /* Tab */
+	CTRL_K = 11,        /* Ctrl+k */
+	CTRL_L = 12,        /* Ctrl+l */
+	ENTER = 13,         /* Enter */
+	CTRL_N = 14,        /* Ctrl-n */
+	CTRL_P = 16,        /* Ctrl-p */
+	CTRL_T = 20,        /* Ctrl-t */
+	CTRL_U = 21,        /* Ctrl+u */
+	CTRL_W = 23,        /* Ctrl+w */
+	ESC = 27,           /* Escape */
+	BACKSPACE =  127    /* Backspace */
+};
+
 static void linenoiseAtExit(void);
 int linenoiseHistoryAdd(const char *line);
 static void refreshLine(struct linenoiseState *l);
-int linenoiseEditInsert(struct linenoiseState *l, int c);
-void linenoiseEditMoveLeft(struct linenoiseState *l);
-void linenoiseEditMoveRight(struct linenoiseState *l);
-void linenoiseEditHistoryNext(struct linenoiseState *l, int dir);
-void linenoiseEditDelete(struct linenoiseState *l);
-void linenoiseEditBackspace(struct linenoiseState *l);
-void linenoiseEditDeletePrevWord(struct linenoiseState *l);
+
+/* Debugging macro. */
+#if 0
+#define lndebugs(str) lndebug(str, NULL)
+FILE *lndebug_fp = NULL;
+#define lndebug(...) \
+    do { \
+        if (lndebug_fp == NULL) { \
+            lndebug_fp = fopen("/tmp/lndebug.txt","a"); \
+            fprintf(lndebug_fp, \
+            "[%d %d %d] p: %d, rows: %d, rpos: %d, max: %d, oldmax: %d\n", \
+            (int)l->len,(int)l->pos,(int)l->oldpos,plen,rows,rpos, \
+            (int)l->maxrows,old_rows); \
+        } \
+        fprintf(lndebug_fp, ", " __VA_ARGS__); \
+        fflush(lndebug_fp); \
+    } while (0)
+#else
+#define lndebugs(str) lndebug(str, NULL)
+#define lndebug(fmt, ...)
+#endif
 
 /* ======================= Low level terminal handling ====================== */
 
@@ -209,18 +256,69 @@ static void disableRawMode(int fd) {
         rawmode = 0;
 }
 
+/* Use the ESC [6n escape sequence to query the horizontal cursor position
+ * and return it. On error -1 is returned, on success the position of the
+ * cursor. */
+static int getCursorPosition(int ifd, int ofd) {
+    char buf[32];
+    int cols, rows;
+    unsigned int i = 0;
+
+    /* Report cursor location */
+    if (write(ofd, "\x1b[6n", 4) != 4) return -1;
+
+    /* Read the response: ESC [ rows ; cols R */
+    while (i < sizeof(buf)-1) {
+        if (read(ifd,buf+i,1) != 1) break;
+        if (buf[i] == 'R') break;
+        i++;
+    }
+    buf[i] = '\0';
+
+    /* Parse it. */
+    if (buf[0] != ESC || buf[1] != '[') return -1;
+    if (sscanf(buf+2,"%d;%d",&rows,&cols) != 2) return -1;
+    return cols;
+}
+
 /* Try to get the number of columns in the current terminal, or assume 80
  * if it fails. */
-static int getColumns(void) {
+static int getColumns(int ifd, int ofd) {
     struct winsize ws;
 
-    if (ioctl(1, TIOCGWINSZ, &ws) == -1 || ws.ws_col == 0) return 80;
-    return ws.ws_col;
+    if (ioctl(1, TIOCGWINSZ, &ws) == -1 || ws.ws_col == 0) {
+        /* ioctl() failed. Try to query the terminal itself. */
+        int start, cols;
+
+        /* Get the initial position so we can restore it later. */
+        start = getCursorPosition(ifd,ofd);
+        if (start == -1) goto failed;
+
+        /* Go to right margin and get position. */
+        if (write(ofd,"\x1b[999C",6) != 6) goto failed;
+        cols = getCursorPosition(ifd,ofd);
+        if (cols == -1) goto failed;
+
+        /* Restore position. */
+        if (cols > start) {
+            char seq[32];
+            snprintf(seq,32,"\x1b[%dD",cols-start);
+            if (write(ofd,seq,strlen(seq)) == -1) {
+                /* Can't recover... */
+            }
+        }
+        return cols;
+    } else {
+        return ws.ws_col;
+    }
+
+failed:
+    return 80;
 }
 
 /* Clear the screen. Used to handle ctrl+l */
 void linenoiseClearScreen(void) {
-    if (write(STDIN_FILENO,"\x1b[H\x1b[2J",7) <= 0) {
+    if (write(STDOUT_FILENO,"\x1b[H\x1b[2J",7) <= 0) {
         /* nothing to do, just to avoid warning. */
     }
 }
@@ -246,7 +344,7 @@ static void freeCompletions(linenoiseCompletions *lc) {
 /* This is an helper function for linenoiseEdit() and is called when the
  * user types the <tab> key in order to complete the string currently in the
  * input.
- * 
+ *
  * The state of the editing is encapsulated into the pointed linenoiseState
  * structure as described in the structure definition. */
 static int completeLine(struct linenoiseState *ls) {
@@ -275,7 +373,7 @@ static int completeLine(struct linenoiseState *ls) {
                 refreshLine(ls);
             }
 
-            nread = read(ls->fd,&c,1);
+            nread = read(ls->ifd,&c,1);
             if (nread <= 0) {
                 freeCompletions(&lc);
                 return -1;
@@ -316,16 +414,51 @@ void linenoiseSetCompletionCallback(linenoiseCompletionCallback *fn) {
  * in order to add completion options given the input string when the
  * user typed <tab>. See the example.c source code for a very easy to
  * understand example. */
-void linenoiseAddCompletion(linenoiseCompletions *lc, char *str) {
+void linenoiseAddCompletion(linenoiseCompletions *lc, const char *str) {
     size_t len = strlen(str);
-    char *copy = malloc(len+1);
+    char *copy, **cvec;
+
+    copy = malloc(len+1);
+    if (copy == NULL) return;
     memcpy(copy,str,len+1);
-    lc->cvec = realloc(lc->cvec,sizeof(char*)*(lc->len+1));
+    cvec = realloc(lc->cvec,sizeof(char*)*(lc->len+1));
+    if (cvec == NULL) {
+        free(copy);
+        return;
+    }
+    lc->cvec = cvec;
     lc->cvec[lc->len++] = copy;
 }
 
 /* =========================== Line editing ================================= */
 
+/* We define a very simple "append buffer" structure, that is an heap
+ * allocated string where we can append to. This is useful in order to
+ * write all the escape sequences in a buffer and flush them to the standard
+ * output in a single call, to avoid flickering effects. */
+struct abuf {
+    char *b;
+    int len;
+};
+
+static void abInit(struct abuf *ab) {
+    ab->b = NULL;
+    ab->len = 0;
+}
+
+static void abAppend(struct abuf *ab, const char *s, int len) {
+    char *new = realloc(ab->b,ab->len+len);
+
+    if (new == NULL) return;
+    memcpy(new+ab->len,s,len);
+    ab->b = new;
+    ab->len += len;
+}
+
+static void abFree(struct abuf *ab) {
+    free(ab->b);
+}
+
 /* Single line low level line refresh.
  *
  * Rewrite the currently edited line accordingly to the buffer content,
@@ -333,11 +466,12 @@ void linenoiseAddCompletion(linenoiseCompletions *lc, char *str) {
 static void refreshSingleLine(struct linenoiseState *l) {
     char seq[64];
     size_t plen = strlen(l->prompt);
-    int fd = l->fd;
+    int fd = l->ofd;
     char *buf = l->buf;
     size_t len = l->len;
     size_t pos = l->pos;
-    
+    struct abuf ab;
+
     while((plen+pos) >= l->cols) {
         buf++;
         len--;
@@ -347,18 +481,21 @@ static void refreshSingleLine(struct linenoiseState *l) {
         len--;
     }
 
+    abInit(&ab);
     /* Cursor to left edge */
-    snprintf(seq,64,"\x1b[0G");
-    if (write(fd,seq,strlen(seq)) == -1) return;
+    snprintf(seq,64,"\r");
+    abAppend(&ab,seq,strlen(seq));
     /* Write the prompt and the current buffer content */
-    if (write(fd,l->prompt,strlen(l->prompt)) == -1) return;
-    if (write(fd,buf,len) == -1) return;
+    abAppend(&ab,l->prompt,strlen(l->prompt));
+    abAppend(&ab,buf,len);
     /* Erase to right */
     snprintf(seq,64,"\x1b[0K");
-    if (write(fd,seq,strlen(seq)) == -1) return;
+    abAppend(&ab,seq,strlen(seq));
     /* Move cursor to original position. */
-    snprintf(seq,64,"\x1b[0G\x1b[%dC", (int)(pos+plen));
-    if (write(fd,seq,strlen(seq)) == -1) return;
+    snprintf(seq,64,"\r\x1b[%dC", (int)(pos+plen));
+    abAppend(&ab,seq,strlen(seq));
+    if (write(fd,ab.b,ab.len) == -1) {} /* Can't recover from write error. */
+    abFree(&ab);
 }
 
 /* Multi line low level line refresh.
@@ -371,47 +508,38 @@ static void refreshMultiLine(struct linenoiseState *l) {
     int rows = (plen+l->len+l->cols-1)/l->cols; /* rows used by current buf. */
     int rpos = (plen+l->oldpos+l->cols)/l->cols; /* cursor relative row. */
     int rpos2; /* rpos after refresh. */
+    int col; /* colum position, zero-based. */
     int old_rows = l->maxrows;
-    int fd = l->fd, j;
+    int fd = l->ofd, j;
+    struct abuf ab;
 
     /* Update maxrows if needed. */
     if (rows > (int)l->maxrows) l->maxrows = rows;
 
-#ifdef LN_DEBUG
-    FILE *fp = fopen("/tmp/debug.txt","a");
-    fprintf(fp,"[%d %d %d] p: %d, rows: %d, rpos: %d, max: %d, oldmax: %d",
-        (int)l->len,(int)l->pos,(int)l->oldpos,plen,rows,rpos,(int)l->maxrows,old_rows);
-#endif
-
     /* First step: clear all the lines used before. To do so start by
      * going to the last row. */
+    abInit(&ab);
     if (old_rows-rpos > 0) {
-#ifdef LN_DEBUG
-        fprintf(fp,", go down %d", old_rows-rpos);
-#endif
+        lndebug("go down %d", old_rows-rpos);
         snprintf(seq,64,"\x1b[%dB", old_rows-rpos);
-        if (write(fd,seq,strlen(seq)) == -1) return;
+        abAppend(&ab,seq,strlen(seq));
     }
 
     /* Now for every row clear it, go up. */
     for (j = 0; j < old_rows-1; j++) {
-#ifdef LN_DEBUG
-        fprintf(fp,", clear+up");
-#endif
-        snprintf(seq,64,"\x1b[0G\x1b[0K\x1b[1A");
-        if (write(fd,seq,strlen(seq)) == -1) return;
+        lndebugs("clear+up");
+        snprintf(seq,64,"\r\x1b[0K\x1b[1A");
+        abAppend(&ab,seq,strlen(seq));
     }
 
     /* Clean the top line. */
-#ifdef LN_DEBUG
-    fprintf(fp,", clear");
-#endif
-    snprintf(seq,64,"\x1b[0G\x1b[0K");
-    if (write(fd,seq,strlen(seq)) == -1) return;
-    
+    lndebugs("clear");
+    snprintf(seq,64,"\r\x1b[0K");
+    abAppend(&ab,seq,strlen(seq));
+
     /* Write the prompt and the current buffer content */
-    if (write(fd,l->prompt,strlen(l->prompt)) == -1) return;
-    if (write(fd,l->buf,l->len) == -1) return;
+    abAppend(&ab,l->prompt,strlen(l->prompt));
+    abAppend(&ab,l->buf,l->len);
 
     /* If we are at the very end of the screen with our prompt, we need to
      * emit a newline and move the prompt to the first column. */
@@ -419,42 +547,39 @@ static void refreshMultiLine(struct linenoiseState *l) {
         l->pos == l->len &&
         (l->pos+plen) % l->cols == 0)
     {
-#ifdef LN_DEBUG
-        fprintf(fp,", <newline>");
-#endif
-        if (write(fd,"\n",1) == -1) return;
-        snprintf(seq,64,"\x1b[0G");
-        if (write(fd,seq,strlen(seq)) == -1) return;
+        lndebugs("<newline>");
+        abAppend(&ab,"\n",1);
+        snprintf(seq,64,"\r");
+        abAppend(&ab,seq,strlen(seq));
         rows++;
         if (rows > (int)l->maxrows) l->maxrows = rows;
     }
 
     /* Move cursor to right position. */
     rpos2 = (plen+l->pos+l->cols)/l->cols; /* current cursor relative row. */
-#ifdef LN_DEBUG
-    fprintf(fp,", rpos2 %d", rpos2);
-#endif
+    lndebug("rpos2 %d", rpos2);
+
     /* Go up till we reach the expected positon. */
     if (rows-rpos2 > 0) {
-#ifdef LN_DEBUG
-        fprintf(fp,", go-up %d", rows-rpos2);
-#endif
+        lndebug("go-up %d", rows-rpos2);
         snprintf(seq,64,"\x1b[%dA", rows-rpos2);
-        if (write(fd,seq,strlen(seq)) == -1) return;
+        abAppend(&ab,seq,strlen(seq));
     }
+
     /* Set column. */
-#ifdef LN_DEBUG
-    fprintf(fp,", set col %d", 1+((plen+(int)l->pos) % (int)l->cols));
-#endif
-    snprintf(seq,64,"\x1b[%dG", 1+((plen+(int)l->pos) % (int)l->cols));
-    if (write(fd,seq,strlen(seq)) == -1) return;
+    col = (plen+(int)l->pos) % (int)l->cols;
+    lndebug("set col %d", 1+col);
+    if (col)
+        snprintf(seq,64,"\r\x1b[%dC", col);
+    else
+        snprintf(seq,64,"\r");
+    abAppend(&ab,seq,strlen(seq));
 
+    lndebugs("\n");
     l->oldpos = l->pos;
 
-#ifdef LN_DEBUG
-    fprintf(fp,"\n");
-    fclose(fp);
-#endif
+    if (write(fd,ab.b,ab.len) == -1) {} /* Can't recover from write error. */
+    abFree(&ab);
 }
 
 /* Calls the two low level functions refreshSingleLine() or
@@ -469,7 +594,7 @@ static void refreshLine(struct linenoiseState *l) {
 /* Insert the character 'c' at cursor current position.
  *
  * On error writing to the terminal -1 is returned, otherwise 0. */
-int linenoiseEditInsert(struct linenoiseState *l, int c) {
+int linenoiseEditInsert(struct linenoiseState *l, char c) {
     if (l->len < l->buflen) {
         if (l->len == l->pos) {
             l->buf[l->pos] = c;
@@ -479,7 +604,7 @@ int linenoiseEditInsert(struct linenoiseState *l, int c) {
             if ((!mlmode && l->plen+l->len < l->cols) /* || mlmode */) {
                 /* Avoid a full update of the line in the
                  * trivial case. */
-                if (write(l->fd,&c,1) == -1) return -1;
+                if (write(l->ofd,&c,1) == -1) return -1;
             } else {
                 refreshLine(l);
             }
@@ -511,6 +636,22 @@ void linenoiseEditMoveRight(struct linenoiseState *l) {
     }
 }
 
+/* Move cursor to the start of the line. */
+void linenoiseEditMoveHome(struct linenoiseState *l) {
+    if (l->pos != 0) {
+        l->pos = 0;
+        refreshLine(l);
+    }
+}
+
+/* Move cursor to the end of the line. */
+void linenoiseEditMoveEnd(struct linenoiseState *l) {
+    if (l->pos != l->len) {
+        l->pos = l->len;
+        refreshLine(l);
+    }
+}
+
 /* Substitute the currently edited line with the next or previous history
  * entry as specified by 'dir'. */
 #define LINENOISE_HISTORY_NEXT 0
@@ -583,38 +724,39 @@ void linenoiseEditDeletePrevWord(struct linenoiseState *l) {
  * when ctrl+d is typed.
  *
  * The function returns the length of the current buffer. */
-static int linenoiseEdit(int fd, char *buf, size_t buflen, const char *prompt)
+static int linenoiseEdit(int stdin_fd, int stdout_fd, char *buf, size_t buflen, const char *prompt)
 {
     struct linenoiseState l;
 
     /* Populate the linenoise state that we pass to functions implementing
      * specific editing functionalities. */
-    l.fd = fd;
+    l.ifd = stdin_fd;
+    l.ofd = stdout_fd;
     l.buf = buf;
     l.buflen = buflen;
     l.prompt = prompt;
     l.plen = strlen(prompt);
     l.oldpos = l.pos = 0;
     l.len = 0;
-    l.cols = getColumns();
+    l.cols = getColumns(stdin_fd, stdout_fd);
     l.maxrows = 0;
     l.history_index = 0;
 
     /* Buffer starts empty. */
-    buf[0] = '\0';
-    buflen--; /* Make sure there is always space for the nulterm */
+    l.buf[0] = '\0';
+    l.buflen--; /* Make sure there is always space for the nulterm */
 
     /* The latest history entry is always our current buffer, that
      * initially is just an empty string. */
     linenoiseHistoryAdd("");
-    
-    if (write(fd,prompt,l.plen) == -1) return -1;
+
+    if (write(l.ofd,prompt,l.plen) == -1) return -1;
     while(1) {
         char c;
         int nread;
-        char seq[2], seq2[2];
+        char seq[3];
 
-        nread = read(fd,&c,1);
+        nread = read(l.ifd,&c,1);
         if (nread <= 0) return l.len;
 
         /* Only autocomplete when the callback is set. It returns < 0 when
@@ -629,19 +771,20 @@ static int linenoiseEdit(int fd, char *buf, size_t buflen, const char *prompt)
         }
 
         switch(c) {
-        case 13:    /* enter */
+        case ENTER:    /* enter */
             history_len--;
             free(history[history_len]);
+            if (mlmode) linenoiseEditMoveEnd(&l);
             return (int)l.len;
-        case 3:     /* ctrl-c */
+        case CTRL_C:     /* ctrl-c */
             errno = EAGAIN;
             return -1;
-        case 127:   /* backspace */
+        case BACKSPACE:   /* backspace */
         case 8:     /* ctrl-h */
             linenoiseEditBackspace(&l);
             break;
-        case 4:     /* ctrl-d, remove char at right of cursor, or of the
-                       line is empty, act as end-of-file. */
+        case CTRL_D:     /* ctrl-d, remove char at right of cursor, or if the
+                            line is empty, act as end-of-file. */
             if (l.len > 0) {
                 linenoiseEditDelete(&l);
             } else {
@@ -650,7 +793,7 @@ static int linenoiseEdit(int fd, char *buf, size_t buflen, const char *prompt)
                 return -1;
             }
             break;
-        case 20:    /* ctrl-t, swaps current character with previous. */
+        case CTRL_T:    /* ctrl-t, swaps current character with previous. */
             if (l.pos > 0 && l.pos < l.len) {
                 int aux = buf[l.pos-1];
                 buf[l.pos-1] = buf[l.pos];
@@ -659,68 +802,97 @@ static int linenoiseEdit(int fd, char *buf, size_t buflen, const char *prompt)
                 refreshLine(&l);
             }
             break;
-        case 2:     /* ctrl-b */
+        case CTRL_B:     /* ctrl-b */
             linenoiseEditMoveLeft(&l);
             break;
-        case 6:     /* ctrl-f */
+        case CTRL_F:     /* ctrl-f */
             linenoiseEditMoveRight(&l);
             break;
-        case 16:    /* ctrl-p */
+        case CTRL_P:    /* ctrl-p */
             linenoiseEditHistoryNext(&l, LINENOISE_HISTORY_PREV);
             break;
-        case 14:    /* ctrl-n */
+        case CTRL_N:    /* ctrl-n */
             linenoiseEditHistoryNext(&l, LINENOISE_HISTORY_NEXT);
             break;
-        case 27:    /* escape sequence */
-            /* Read the next two bytes representing the escape sequence. */
-            if (read(fd,seq,2) == -1) break;
-
-            if (seq[0] == 91 && seq[1] == 68) {
-                /* Left arrow */
-                linenoiseEditMoveLeft(&l);
-            } else if (seq[0] == 91 && seq[1] == 67) {
-                /* Right arrow */
-                linenoiseEditMoveRight(&l);
-            } else if (seq[0] == 91 && (seq[1] == 65 || seq[1] == 66)) {
-                /* Up and Down arrows */
-                linenoiseEditHistoryNext(&l,
-                    (seq[1] == 65) ? LINENOISE_HISTORY_PREV :
-                                     LINENOISE_HISTORY_NEXT);
-            } else if (seq[0] == 91 && seq[1] > 48 && seq[1] < 55) {
-                /* extended escape, read additional two bytes. */
-                if (read(fd,seq2,2) == -1) break;
-                if (seq[1] == 51 && seq2[0] == 126) {
-                    /* Delete key. */
-                    linenoiseEditDelete(&l);
+        case ESC:    /* escape sequence */
+            /* Read the next two bytes representing the escape sequence.
+             * Use two calls to handle slow terminals returning the two
+             * chars at different times. */
+            if (read(l.ifd,seq,1) == -1) break;
+            if (read(l.ifd,seq+1,1) == -1) break;
+
+            /* ESC [ sequences. */
+            if (seq[0] == '[') {
+                if (seq[1] >= '0' && seq[1] <= '9') {
+                    /* Extended escape, read additional byte. */
+                    if (read(l.ifd,seq+2,1) == -1) break;
+                    if (seq[2] == '~') {
+                        switch(seq[1]) {
+                        case '3': /* Delete key. */
+                            linenoiseEditDelete(&l);
+                            break;
+                        }
+                    }
+                } else {
+                    switch(seq[1]) {
+                    case 'A': /* Up */
+                        linenoiseEditHistoryNext(&l, LINENOISE_HISTORY_PREV);
+                        break;
+                    case 'B': /* Down */
+                        linenoiseEditHistoryNext(&l, LINENOISE_HISTORY_NEXT);
+                        break;
+                    case 'C': /* Right */
+                        linenoiseEditMoveRight(&l);
+                        break;
+                    case 'D': /* Left */
+                        linenoiseEditMoveLeft(&l);
+                        break;
+                    case 'H': /* Home */
+                        linenoiseEditMoveHome(&l);
+                        break;
+                    case 'F': /* End*/
+                        linenoiseEditMoveEnd(&l);
+                        break;
+                    }
+                }
+            }
+
+            /* ESC O sequences. */
+            else if (seq[0] == 'O') {
+                switch(seq[1]) {
+                case 'H': /* Home */
+                    linenoiseEditMoveHome(&l);
+                    break;
+                case 'F': /* End*/
+                    linenoiseEditMoveEnd(&l);
+                    break;
                 }
             }
             break;
         default:
             if (linenoiseEditInsert(&l,c)) return -1;
             break;
-        case 21: /* Ctrl+u, delete the whole line. */
+        case CTRL_U: /* Ctrl+u, delete the whole line. */
             buf[0] = '\0';
             l.pos = l.len = 0;
             refreshLine(&l);
             break;
-        case 11: /* Ctrl+k, delete from current to end of line. */
+        case CTRL_K: /* Ctrl+k, delete from current to end of line. */
             buf[l.pos] = '\0';
             l.len = l.pos;
             refreshLine(&l);
             break;
-        case 1: /* Ctrl+a, go to the start of the line */
-            l.pos = 0;
-            refreshLine(&l);
+        case CTRL_A: /* Ctrl+a, go to the start of the line */
+            linenoiseEditMoveHome(&l);
             break;
-        case 5: /* ctrl+e, go to the end of the line */
-            l.pos = l.len;
-            refreshLine(&l);
+        case CTRL_E: /* ctrl+e, go to the end of the line */
+            linenoiseEditMoveEnd(&l);
             break;
-        case 12: /* ctrl+l, clear screen */
+        case CTRL_L: /* ctrl+l, clear screen */
             linenoiseClearScreen();
             refreshLine(&l);
             break;
-        case 23: /* ctrl+w, delete previous word */
+        case CTRL_W: /* ctrl+w, delete previous word */
             linenoiseEditDeletePrevWord(&l);
             break;
         }
@@ -728,10 +900,37 @@ static int linenoiseEdit(int fd, char *buf, size_t buflen, const char *prompt)
     return l.len;
 }
 
+/* This special mode is used by linenoise in order to print scan codes
+ * on screen for debugging / development purposes. It is implemented
+ * by the linenoise_example program using the --keycodes option. */
+void linenoisePrintKeyCodes(void) {
+    char quit[4];
+
+    printf("Linenoise key codes debugging mode.\n"
+            "Press keys to see scan codes. Type 'quit' at any time to exit.\n");
+    if (enableRawMode(STDIN_FILENO) == -1) return;
+    memset(quit,' ',4);
+    while(1) {
+        char c;
+        int nread;
+
+        nread = read(STDIN_FILENO,&c,1);
+        if (nread <= 0) continue;
+        memmove(quit,quit+1,sizeof(quit)-1); /* shift string to left. */
+        quit[sizeof(quit)-1] = c; /* Insert current char on the right. */
+        if (memcmp(quit,"quit",sizeof(quit)) == 0) break;
+
+        printf("'%c' %02x (%d) (type quit to exit)\n",
+            isprint(c) ? c : '?', (int)c, (int)c);
+        printf("\r"); /* Go left edge manually, we are in raw mode. */
+        fflush(stdout);
+    }
+    disableRawMode(STDIN_FILENO);
+}
+
 /* This function calls the line editing function linenoiseEdit() using
  * the STDIN file descriptor set in raw mode. */
 static int linenoiseRaw(char *buf, size_t buflen, const char *prompt) {
-    int fd = STDIN_FILENO;
     int count;
 
     if (buflen == 0) {
@@ -739,6 +938,7 @@ static int linenoiseRaw(char *buf, size_t buflen, const char *prompt) {
         return -1;
     }
     if (!isatty(STDIN_FILENO)) {
+        /* Not a tty: read from file / pipe. */
         if (fgets(buf, buflen, stdin) == NULL) return -1;
         count = strlen(buf);
         if (count && buf[count-1] == '\n') {
@@ -746,9 +946,10 @@ static int linenoiseRaw(char *buf, size_t buflen, const char *prompt) {
             buf[count] = '\0';
         }
     } else {
-        if (enableRawMode(fd) == -1) return -1;
-        count = linenoiseEdit(fd, buf, buflen, prompt);
-        disableRawMode(fd);
+        /* Interactive editing. */
+        if (enableRawMode(STDIN_FILENO) == -1) return -1;
+        count = linenoiseEdit(STDIN_FILENO, STDOUT_FILENO, buf, buflen, prompt);
+        disableRawMode(STDIN_FILENO);
         printf("\n");
     }
     return count;
@@ -802,16 +1003,30 @@ static void linenoiseAtExit(void) {
     freeHistory();
 }
 
-/* Using a circular buffer is smarter, but a bit more complex to handle. */
+/* This is the API call to add a new entry in the linenoise history.
+ * It uses a fixed array of char pointers that are shifted (memmoved)
+ * when the history max length is reached in order to remove the older
+ * entry and make room for the new one, so it is not exactly suitable for huge
+ * histories, but will work well for a few hundred of entries.
+ *
+ * Using a circular buffer is smarter, but a bit more complex to handle. */
 int linenoiseHistoryAdd(const char *line) {
     char *linecopy;
 
     if (history_max_len == 0) return 0;
+
+    /* Initialization on first call. */
     if (history == NULL) {
         history = malloc(sizeof(char*)*history_max_len);
         if (history == NULL) return 0;
         memset(history,0,(sizeof(char*)*history_max_len));
     }
+
+    /* Don't add duplicated lines. */
+    if (history_len && !strcmp(history[history_len-1], line)) return 0;
+
+    /* Add an heap allocated copy of the line in the history.
+     * If we reached the max length, remove the older line. */
     linecopy = strdup(line);
     if (!linecopy) return 0;
     if (history_len == history_max_len) {
@@ -858,10 +1073,10 @@ int linenoiseHistorySetMaxLen(int len) {
 
 /* Save the history in the specified file. On success 0 is returned
  * otherwise -1 is returned. */
-int linenoiseHistorySave(char *filename) {
+int linenoiseHistorySave(const char *filename) {
     FILE *fp = fopen(filename,"w");
     int j;
-    
+
     if (fp == NULL) return -1;
     for (j = 0; j < history_len; j++)
         fprintf(fp,"%s\n",history[j]);
@@ -874,15 +1089,15 @@ int linenoiseHistorySave(char *filename) {
  *
  * If the file exists and the operation succeeded 0 is returned, otherwise
  * on error -1 is returned. */
-int linenoiseHistoryLoad(char *filename) {
+int linenoiseHistoryLoad(const char *filename) {
     FILE *fp = fopen(filename,"r");
     char buf[LINENOISE_MAX_LINE];
-    
+
     if (fp == NULL) return -1;
 
     while (fgets(buf,LINENOISE_MAX_LINE,fp) != NULL) {
         char *p;
-        
+
         p = strchr(buf,'\r');
         if (!p) p = strchr(buf,'\n');
         if (p) *p = '\0';
diff --git a/src/linenoise.h b/src/linenoise.h
index f28824d..0e89179 100644
--- a/src/linenoise.h
+++ b/src/linenoise.h
@@ -5,22 +5,22 @@
  *
  * ------------------------------------------------------------------------
  *
- * Copyright (c) 2010, Salvatore Sanfilippo <antirez at gmail dot com>
- * Copyright (c) 2010, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ * Copyright (c) 2010-2014, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2013, Pieter Noordhuis <pcnoordhuis at gmail dot com>
  *
  * All rights reserved.
- * 
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
- * 
+ *
  *  *  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  *
  *  *  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
  *     documentation and/or other materials provided with the distribution.
- * 
+ *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
@@ -37,6 +37,10 @@
 #ifndef __LINENOISE_H
 #define __LINENOISE_H
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef struct linenoiseCompletions {
   size_t len;
   char **cvec;
@@ -44,14 +48,19 @@ typedef struct linenoiseCompletions {
 
 typedef void(linenoiseCompletionCallback)(const char *, linenoiseCompletions *);
 void linenoiseSetCompletionCallback(linenoiseCompletionCallback *);
-void linenoiseAddCompletion(linenoiseCompletions *, char *);
+void linenoiseAddCompletion(linenoiseCompletions *, const char *);
 
 char *linenoise(const char *prompt);
 int linenoiseHistoryAdd(const char *line);
 int linenoiseHistorySetMaxLen(int len);
-int linenoiseHistorySave(char *filename);
-int linenoiseHistoryLoad(char *filename);
+int linenoiseHistorySave(const char *filename);
+int linenoiseHistoryLoad(const char *filename);
 void linenoiseClearScreen(void);
 void linenoiseSetMultiLine(int ml);
+void linenoisePrintKeyCodes(void);
+
+#ifdef __cplusplus
+}
+#endif
 
 #endif /* __LINENOISE_H */