fix bound checking on cursor move

changing most of the vt struct fields to unsigned, to avoid undefined
behaviour and use gotoxy for moving the cursor to correctly bound check
the cursor position

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

diff --git a/spiceterm.c b/spiceterm.c
index bcb38c6593c0105cee5ded71b10a9514085bbc9f..fdcafbc60670a7124af475344edcf9074379ede9 100644 (file)
--- a/spiceterm.c
+++ b/spiceterm.c
@@ -865,10 +865,7 @@ spiceterm_putchar(spiceTerm *vt, gunichar2 ch)
             if (vt->esc_buf[0] == 0) {
                 vt->esc_buf[0] = 1;
             }
-            vt->cy -= vt->esc_buf[0];
-            if (vt->cy < 0) {
-                vt->cy = 0;
-            }
+            spiceterm_gotoxy(vt, vt->cx, vt->cy - vt->esc_buf[0]);
             break;
         case 'B':
         case 'e':
@@ -876,10 +873,7 @@ spiceterm_putchar(spiceTerm *vt, gunichar2 ch)
             if (vt->esc_buf[0] == 0) {
                 vt->esc_buf[0] = 1;
             }
-            vt->cy += vt->esc_buf[0];
-            if (vt->cy >= vt->height) {
-                vt->cy = vt->height - 1;
-            }
+            spiceterm_gotoxy(vt, vt->cx, vt->cy + vt->esc_buf[0]);
             break;
         case 'C':
         case 'a':
@@ -887,20 +881,14 @@ spiceterm_putchar(spiceTerm *vt, gunichar2 ch)
             if (vt->esc_buf[0] == 0) {
                 vt->esc_buf[0] = 1;
             }
-            vt->cx += vt->esc_buf[0];
-            if (vt->cx >= vt->width) {
-                vt->cx = vt->width - 1;
-            }
+            spiceterm_gotoxy(vt, vt->cx + vt->esc_buf[0], vt->cy);
             break;
         case 'D':
             /* move cursor left */
             if (vt->esc_buf[0] == 0) {
                 vt->esc_buf[0] = 1;
             }
-            vt->cx -= vt->esc_buf[0];
-            if (vt->cx < 0) {
-                vt->cx = 0;
-            }
+            spiceterm_gotoxy(vt, vt->cx - vt->esc_buf[0], vt->cy);
             break;
         case 'G':
         case '`':

diff --git a/spiceterm.h b/spiceterm.h
index 7993c6aa01318fd4a83fe065b7e3f9373115ea8c..0e238ca8d924d457fb605ff295b6bb827628513d 100644 (file)
--- a/spiceterm.h
+++ b/spiceterm.h
@@ -112,19 +112,19 @@ typedef struct spiceTerm {
     // cursor
     TextAttributes cur_attrib;
     TextAttributes cur_attrib_saved;
-    int tty_state; // 0 - normal, 1 - ESC, 2 - CSI
+    unsigned int tty_state; // 0 - normal, 1 - ESC, 2 - CSI
     int cx; // cursor x position
     int cy; // cursor y position
     int cx_saved; // saved cursor x position
     int cy_saved; // saved cursor y position
-    int esc_buf[MAX_ESC_PARAMS];
-    int esc_count;
-    int esc_ques;
-    int esc_has_par;
+    unsigned int esc_buf[MAX_ESC_PARAMS];
+    unsigned int esc_count;
+    unsigned int esc_ques;
+    unsigned int esc_has_par;
     char osc_textbuf[4096];
     char osc_cmd;
-    int region_top;
-    int region_bottom;
+    unsigned int region_top;
+    unsigned int region_bottom;
 
     unsigned int charset:1; // G0 or G1
     unsigned int charset_saved:1; // G0 or G1