lineedit: correctly handle prompt longer than screen width. closes bug 3414

diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index c91efd4..fb595c0 100644 (file)
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -80,10 +80,9 @@ struct lineedit_statics {
        volatile unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
        sighandler_t previous_SIGWINCH_handler;
 
-
-       int cmdedit_x;           /* real x terminal position */
-       int cmdedit_y;           /* pseudoreal y terminal position */
-       int cmdedit_prmt_len;    /* length of prompt (without colors etc) */
+       unsigned cmdedit_x;        /* real x terminal position */
+       unsigned cmdedit_y;        /* pseudoreal y terminal position */
+       unsigned cmdedit_prmt_len; /* length of prompt (without colors etc) */
 
        unsigned cursor;
        unsigned command_len;
@@ -199,7 +198,7 @@ static void cmdedit_set_out_char(int next_char)
        {
                bb_putchar(c);
        }
-       if (++cmdedit_x >= (int)cmdedit_termw) {
+       if (++cmdedit_x >= cmdedit_termw) {
                /* terminal is scrolled down */
                cmdedit_y++;
                cmdedit_x = 0;
@@ -262,12 +261,12 @@ static void input_backward(unsigned num)
                return;
        cursor -= num;
 
-       if ((unsigned)cmdedit_x >= num) {
+       if (cmdedit_x >= num) {
                cmdedit_x -= num;
                if (num <= 4) {
                        /* This is longer by 5 bytes on x86.
-                        * Also gets mysteriously
-                        * miscompiled for some ARM users.
+                        * Also gets miscompiled for ARM users
+                        * (busybox.net/bugs/view.php?id=2274).
                         * printf(("\b\b\b\b" + 4) - num);
                         * return;
                         */
@@ -282,9 +281,12 @@ static void input_backward(unsigned num)
 
        /* Need to go one or more lines up */
        num -= cmdedit_x;
-       count_y = 1 + (num / cmdedit_termw);
-       cmdedit_y -= count_y;
-       cmdedit_x = cmdedit_termw * count_y - num;
+       {
+               unsigned w = cmdedit_termw; /* volatile var */
+               count_y = 1 + (num / w);
+               cmdedit_y -= count_y;
+               cmdedit_x = w * count_y - num;
+       }
        /* go to 1st column; go up; go to correct column */
        printf("\r" "\033[%dA" "\033[%dC", count_y, cmdedit_x);
 }
@@ -292,10 +294,12 @@ static void input_backward(unsigned num)
 static void put_prompt(void)
 {
        out1str(cmdedit_prompt);
-       cmdedit_x = cmdedit_prmt_len;
        cursor = 0;
-// Huh? what if cmdedit_prmt_len >= width?
-       cmdedit_y = 0;                  /* new quasireal y */
+       {
+               unsigned w = cmdedit_termw; /* volatile var */
+               cmdedit_y = cmdedit_prmt_len / w; /* new quasireal y */
+               cmdedit_x = cmdedit_prmt_len % w;
+       }
 }
 
 /* draw prompt, editor line, and clear tail */