terminal: Basic vt100 escape codes

Implements correct behaviour for vt100 cursor movement, erasing, custom
tabs, and reporting. Includes relevant terminal modes.

Signed-off-by: Callum Lowcay <callum@callumscode.com>

diff --git a/clients/terminal.c b/clients/terminal.c
index e900298..60da93a 100644 (file)
--- a/clients/terminal.c
+++ b/clients/terminal.c
@@ -56,6 +56,13 @@ static int option_fullscreen;
 #define MAX_RESPONSE           11
 #define MAX_ESCAPE             64
 
+/* Terminal modes */
+#define MODE_SHOW_CURSOR       0x00000001
+#define MODE_INVERSE           0x00000002
+#define MODE_AUTOWRAP          0x00000004
+#define MODE_AUTOREPEAT                0x00000008
+#define MODE_LF_NEWLINE                0x00000010
+
 union utf8_char {
        unsigned char byte[4];
        uint32_t ch;
@@ -185,13 +192,18 @@ struct terminal {
        struct window *window;
        struct display *display;
        union utf8_char *data;
+       char *tab_ruler;
        struct attr *data_attr;
        struct attr curr_attr;
+       uint32_t mode;
        char origin_mode;
+       char saved_origin_mode;
+       struct attr saved_attr;
        union utf8_char last_char;
        int margin_top, margin_bottom;
        int data_pitch, attr_pitch;  /* The width in bytes of a line */
        int width, height, start, row, column;
+       int saved_row, saved_column;
        int fd, master;
        GIOChannel *channel;
        uint32_t modifiers;
@@ -209,14 +221,39 @@ struct terminal {
        cairo_font_face_t *font_normal, *font_bold;
 };
 
+/* Create default tab stops, every 8 characters */
+static void
+terminal_init_tabs(struct terminal *terminal)
+{
+       int i = 0;
+       
+       while (i < terminal->width) {
+               if (i % 8 == 0)
+                       terminal->tab_ruler[i] = 1;
+               else
+                       terminal->tab_ruler[i] = 0;
+               i++;
+       }
+}
+
 static void
 terminal_init(struct terminal *terminal)
 {
        terminal->curr_attr = terminal->color_scheme->default_attr;
        terminal->origin_mode = 0;
+       terminal->mode = MODE_SHOW_CURSOR |
+                        MODE_AUTOREPEAT |
+                        MODE_AUTOWRAP;
 
        terminal->row = 0;
        terminal->column = 0;
+
+       terminal->saved_attr = terminal->curr_attr;
+       terminal->saved_origin_mode = terminal->origin_mode;
+       terminal->saved_row = terminal->row;
+       terminal->saved_column = terminal->column;
+
+       if (terminal->tab_ruler != NULL) terminal_init_tabs(terminal);
 }
 
 static void
@@ -362,6 +399,7 @@ terminal_resize(struct terminal *terminal, int width, int height)
        size_t size;
        union utf8_char *data;
        struct attr *data_attr;
+       char *tab_ruler;
        int data_pitch, attr_pitch;
        int i, l, total_rows, start;
        struct rectangle rectangle;
@@ -375,7 +413,9 @@ terminal_resize(struct terminal *terminal, int width, int height)
        data = malloc(size);
        attr_pitch = width * sizeof(struct attr);
        data_attr = malloc(attr_pitch * height);
+       tab_ruler = malloc(width);
        memset(data, 0, size);
+       memset(tab_ruler, 0, width);
        attr_init(data_attr, terminal->curr_attr, width * height);
        if (terminal->data && terminal->data_attr) {
                if (width > terminal->width)
@@ -402,6 +442,7 @@ terminal_resize(struct terminal *terminal, int width, int height)
 
                free(terminal->data);
                free(terminal->data_attr);
+               free(terminal->tab_ruler);
        }
 
        terminal->data_pitch = data_pitch;
@@ -412,6 +453,8 @@ terminal_resize(struct terminal *terminal, int width, int height)
                terminal->margin_bottom = terminal->height - 1;
        terminal->data = data;
        terminal->data_attr = data_attr;
+       terminal->tab_ruler = tab_ruler;
+       terminal_init_tabs(terminal);
 
        if (terminal->row >= terminal->height)
                terminal->row = terminal->height - 1;
@@ -473,7 +516,7 @@ terminal_draw_contents(struct terminal *terminal)
                union utf8_char c;
                char null;
        } toShow;
-       int foreground, background, bold, underline;
+       int foreground, background, bold, underline, tmp;
        int text_x, text_y;
        cairo_surface_t *surface;
        double d;
@@ -508,8 +551,9 @@ terminal_draw_contents(struct terminal *terminal)
                        /* get the attributes for this character cell */
                        attr = terminal_get_attr(terminal, row, col);
                        if ((attr.a & ATTRMASK_INVERSE) ||
-                               (terminal->focused &&
-                               terminal->row == row && terminal->column == col))
+                               ((terminal->mode & MODE_SHOW_CURSOR) &&
+                               terminal->focused && terminal->row == row &&
+                               terminal->column == col))
                        {
                                foreground = attr.bg;
                                background = attr.fg;
@@ -517,6 +561,11 @@ terminal_draw_contents(struct terminal *terminal)
                                foreground = attr.fg;
                                background = attr.bg;
                        }
+                       if (terminal->mode & MODE_INVERSE) {
+                               tmp = foreground;
+                               foreground = background;
+                               background = tmp;
+                       }
                        bold = attr.a & (ATTRMASK_BOLD | ATTRMASK_BLINK);
                        underline = attr.a & ATTRMASK_UNDERLINE;
 
@@ -559,7 +608,7 @@ terminal_draw_contents(struct terminal *terminal)
                }
        }
 
-       if (!terminal->focused) {
+       if ((terminal->mode & MODE_SHOW_CURSOR) && !terminal->focused) {
                d = 0.5;
 
                cairo_set_line_width(cr, 1);
@@ -626,8 +675,29 @@ handle_sgr(struct terminal *terminal, int code);
 static void
 handle_term_parameter(struct terminal *terminal, int code, int sr)
 {
+       int i;
+
        if (terminal->qmark_flag) {
                switch(code) {
+               case 3:  /* DECCOLM */
+                       if (sr)
+                               terminal_resize(terminal, 132, 24);
+                       else
+                               terminal_resize(terminal, 80, 24);
+                       
+                       /* set columns, but also home cursor and clear screen */
+                       terminal->row = 0; terminal->column = 0;
+                       for (i = 0; i < terminal->height; i++) {
+                               memset(terminal_get_row(terminal, i),
+                                   0, terminal->data_pitch);
+                               attr_init(terminal_get_attr_row(terminal, i),
+                                   terminal->curr_attr, terminal->width);
+                       }
+                       break;
+               case 5:  /* DECSCNM */
+                       if (sr) terminal->mode |=  MODE_INVERSE;
+                       else    terminal->mode &= ~MODE_INVERSE;
+                       break;
                case 6:  /* DECOM */
                        terminal->origin_mode = sr;
                        if (terminal->origin_mode)
@@ -636,12 +706,28 @@ handle_term_parameter(struct terminal *terminal, int code, int sr)
                                terminal->row = 0;
                        terminal->column = 0;
                        break;
+               case 7:  /* DECAWM */
+                       if (sr) terminal->mode |=  MODE_AUTOWRAP;
+                       else    terminal->mode &= ~MODE_AUTOWRAP;
+                       break;
+               case 8:  /* DECARM */
+                       if (sr) terminal->mode |=  MODE_AUTOREPEAT;
+                       else    terminal->mode &= ~MODE_AUTOREPEAT;
+                       break;
+               case 25:
+                       if (sr) terminal->mode |=  MODE_SHOW_CURSOR;
+                       else    terminal->mode &= ~MODE_SHOW_CURSOR;
+                       break;
                default:
                        fprintf(stderr, "Unknown parameter: ?%d\n", code);
                        break;
                }
        } else {
                switch(code) {
+               case 20: /* LNM */
+                       if (sr) terminal->mode |=  MODE_LF_NEWLINE;
+                       else    terminal->mode &= ~MODE_LF_NEWLINE;
+                       break;
                default:
                        fprintf(stderr, "Unknown parameter: %d\n", code);
                        break;
@@ -655,8 +741,9 @@ handle_escape(struct terminal *terminal)
        union utf8_char *row;
        struct attr *attr_row;
        char *p;
-       int i, count, top, bottom;
+       int i, count, x, y, top, bottom;
        int args[10], set[10] = { 0, };
+       char response[MAX_RESPONSE] = {0, };
 
        terminal->escape[terminal->escape_length++] = '\0';
        i = 0;
@@ -676,58 +763,135 @@ handle_escape(struct terminal *terminal)
        }
        
        switch (*p) {
-       case 'A':
+       case 'A':    /* CUU */
                count = set[0] ? args[0] : 1;
-               if (terminal->row - count >= 0)
+               if (count == 0) count = 1;
+               if (terminal->row - count >= terminal->margin_top)
                        terminal->row -= count;
                else
-                       terminal->row = 0;
+                       terminal->row = terminal->margin_top;
                break;
-       case 'B':
+       case 'B':    /* CUD */
                count = set[0] ? args[0] : 1;
-               if (terminal->row + count < terminal->height)
+               if (count == 0) count = 1;
+               if (terminal->row + count <= terminal->margin_bottom)
                        terminal->row += count;
                else
-                       terminal->row = terminal->height;
+                       terminal->row = terminal->margin_bottom;
                break;
-       case 'C':
+       case 'C':    /* CUF */
                count = set[0] ? args[0] : 1;
-               if (terminal->column + count < terminal->width)
+               if (count == 0) count = 1;
+               if ((terminal->column + count) < terminal->width)
                        terminal->column += count;
                else
-                       terminal->column = terminal->width;
+                       terminal->column = terminal->width - 1;
                break;
-       case 'D':
+       case 'D':    /* CUB */
                count = set[0] ? args[0] : 1;
-               if (terminal->column - count >= 0)
+               if (count == 0) count = 1;
+               if ((terminal->column - count) >= 0)
                        terminal->column -= count;
                else
                        terminal->column = 0;
                break;
-       case 'J':
-               row = terminal_get_row(terminal, terminal->row);
-               attr_row = terminal_get_attr_row(terminal, terminal->row);
-               memset(&row[terminal->column], 0, (terminal->width - terminal->column) * sizeof(union utf8_char));
-               attr_init(&attr_row[terminal->column], terminal->curr_attr, (terminal->width - terminal->column));
-               for (i = terminal->row + 1; i < terminal->height; i++) {
-                       memset(terminal_get_row(terminal, i), 0, terminal->width * sizeof(union utf8_char));
-                       attr_init(terminal_get_attr_row(terminal, i), terminal->curr_attr, terminal->width);
+       case 'E':    /* CNL */
+               count = set[0] ? args[0] : 1;
+               if (terminal->row + count <= terminal->margin_bottom)
+                       terminal->row += count;
+               else
+                       terminal->row = terminal->margin_bottom;
+               terminal->column = 0;
+               break;
+       case 'F':    /* CPL */
+               count = set[0] ? args[0] : 1;
+               if (terminal->row - count >= terminal->margin_top)
+                       terminal->row -= count;
+               else
+                       terminal->row = terminal->margin_top;
+               terminal->column = 0;
+               break;
+       case 'G':    /* CHA */
+               y = set[0] ? args[0] : 1;
+               y = y <= 0 ? 1 : y > terminal->width ? terminal->width : y;
+               
+               terminal->column = y - 1;
+               break;
+       case 'f':    /* HVP */
+       case 'H':    /* CUP */
+               x = (set[1] ? args[1] : 1) - 1;
+               x = x < 0 ? 0 :
+                   (x >= terminal->width ? terminal->width - 1 : x);
+               
+               y = (set[0] ? args[0] : 1) - 1;
+               if (terminal->origin_mode) {
+                       y += terminal->margin_top;
+                       y = y < terminal->margin_top ? terminal->margin_top :
+                           (y > terminal->margin_bottom ? terminal->margin_bottom : y);
+               } else {
+                       y = y < 0 ? 0 :
+                           (y >= terminal->height ? terminal->height - 1 : y);
                }
+               
+               terminal->row = y;
+               terminal->column = x;
                break;
-       case 'G':
-               if (set[0])
-                       terminal->column = args[0] - 1;
+       case 'I':    /* CHT */
+               count = set[0] ? args[0] : 1;
+               if (count == 0) count = 1;
+               while (count > 0 && terminal->column < terminal->width) {
+                       if (terminal->tab_ruler[terminal->column]) count--;
+                       terminal->column++;
+               }
+               terminal->column--;
                break;
-       case 'H':
-       case 'f':
-               terminal->row = set[0] ? args[0] - 1 : 0;
-               terminal->column = set[1] ? args[1] - 1 : 0;
+       case 'J':    /* ED */
+               row = terminal_get_row(terminal, terminal->row);
+               attr_row = terminal_get_attr_row(terminal, terminal->row);
+               if (!set[0] || args[0] == 0 || args[0] > 2) {
+                       memset(&row[terminal->column],
+                              0, (terminal->width - terminal->column) * sizeof(union utf8_char));
+                       attr_init(&attr_row[terminal->column],
+                              terminal->curr_attr, terminal->width - terminal->column);
+                       for (i = terminal->row + 1; i < terminal->height; i++) {
+                               memset(terminal_get_row(terminal, i),
+                                   0, terminal->data_pitch);
+                               attr_init(terminal_get_attr_row(terminal, i),
+                                   terminal->curr_attr, terminal->width);
+                       }
+               } else if (args[0] == 1) {
+                       memset(row, 0, (terminal->column+1) * sizeof(union utf8_char));
+                       attr_init(attr_row, terminal->curr_attr, terminal->column+1);
+                       for (i = 0; i < terminal->row; i++) {
+                               memset(terminal_get_row(terminal, i),
+                                   0, terminal->data_pitch);
+                               attr_init(terminal_get_attr_row(terminal, i),
+                                   terminal->curr_attr, terminal->width);
+                       }
+               } else if (args[0] == 2) {
+                       for (i = 0; i < terminal->height; i++) {
+                               memset(terminal_get_row(terminal, i),
+                                   0, terminal->data_pitch);
+                               attr_init(terminal_get_attr_row(terminal, i),
+                                   terminal->curr_attr, terminal->width);
+                       }
+               }
                break;
-       case 'K':
+       case 'K':    /* EL */
                row = terminal_get_row(terminal, terminal->row);
                attr_row = terminal_get_attr_row(terminal, terminal->row);
-               memset(&row[terminal->column], 0, (terminal->width - terminal->column) * sizeof(union utf8_char));
-               attr_init(&attr_row[terminal->column], terminal->curr_attr, (terminal->width - terminal->column));
+               if (!set[0] || args[0] == 0 || args[0] > 2) {
+                       memset(&row[terminal->column], 0,
+                           (terminal->width - terminal->column) * sizeof(union utf8_char));
+                       attr_init(&attr_row[terminal->column], terminal->curr_attr,
+                           terminal->width - terminal->column);
+               } else if (args[0] == 1) {
+                       memset(row, 0, (terminal->column+1) * sizeof(union utf8_char));
+                       attr_init(attr_row, terminal->curr_attr, terminal->column+1);
+               } else if (args[0] == 2) {
+                       memset(row, 0, terminal->data_pitch);
+                       attr_init(attr_row, terminal->curr_attr, terminal->width);
+               }
                break;
        case 'S':    /* SU */
                terminal_scroll(terminal, set[0] ? args[0] : 1);
@@ -735,6 +899,46 @@ handle_escape(struct terminal *terminal)
        case 'T':    /* SD */
                terminal_scroll(terminal, 0 - (set[0] ? args[0] : 1));
                break;
+       case 'Z':    /* CBT */
+               count = set[0] ? args[0] : 1;
+               if (count == 0) count = 1;
+               while (count > 0 && terminal->column >= 0) {
+                       if (terminal->tab_ruler[terminal->column]) count--;
+                       terminal->column--;
+               }
+               terminal->column++;
+               break;
+       case '`':    /* HPA */
+               y = set[0] ? args[0] : 1;
+               y = y <= 0 ? 1 : y > terminal->width ? terminal->width : y;
+               
+               terminal->column = y - 1;
+               break;
+       case 'b':    /* REP */
+               count = set[0] ? args[0] : 1;
+               if (count == 0) count = 1;
+               if (terminal->last_char.byte[0])
+                       for (i = 0; i < count; i++)
+                               handle_char(terminal, terminal->last_char);
+               terminal->last_char.byte[0] = 0;
+               break;
+       case 'c':    /* Primary DA */
+               write(terminal->master, "\e[?1;2c", 7);
+               sleep(1);
+               break;
+       case 'd':    /* VPA */
+               x = set[0] ? args[0] : 1;
+               x = x <= 0 ? 1 : x > terminal->height ? terminal->height : x;
+               
+               terminal->row = x - 1;
+               break;
+       case 'g':    /* TBC */
+               if (!set[0] || args[0] == 0) {
+                       terminal->tab_ruler[terminal->column] = 0;
+               } else if (args[0] == 3) {
+                       memset(terminal->tab_ruler, 0, terminal->width);
+               }
+               break;
        case 'h':    /* SM */
                for(i = 0; i < 10 && set[i]; i++) {
                        handle_term_parameter(terminal, args[i], 1);
@@ -766,6 +970,19 @@ handle_escape(struct terminal *terminal)
                        }
                }
                break;
+       case 'n':    /* DSR */
+               i = set[0] ? args[0] : 0;
+               if (i == 0 || i == 5) {
+                       write(terminal->master, "\e[0n", 4);
+               } else if (i == 6) {
+                       snprintf(response, MAX_RESPONSE, "\e[%d;%dR",
+                                terminal->origin_mode ?
+                                    terminal->row+terminal->margin_top : terminal->row+1,
+                                terminal->column+1);
+                       write(terminal->master, response, strlen(response));
+               }
+               sleep(1);  /* is this required? why? */
+               break;
        case 'r':
                if(!set[0]) {
                        terminal->margin_top = 0;
@@ -793,6 +1010,14 @@ handle_escape(struct terminal *terminal)
                        terminal->column = 0;
                }
                break;
+       case 's':
+               terminal->saved_row = terminal->row;
+               terminal->saved_column = terminal->column;
+               break;
+       case 'u':
+               terminal->row = terminal->saved_row;
+               terminal->column = terminal->saved_column;
+               break;
        default:
                fprintf(stderr, "Unknown CSI escape: %c\n", *p);
                break;
@@ -820,6 +1045,24 @@ handle_non_csi_escape(struct terminal *terminal, char code)
                        terminal_scroll(terminal, +1);
                }
                break;
+       case 'c':    /* RIS */
+               terminal_init(terminal);
+               break;
+       case 'H':    /* HTS */
+               terminal->tab_ruler[terminal->column] = 1;
+               break;
+       case '7':    /* DECSC */
+               terminal->saved_row = terminal->row;
+               terminal->saved_column = terminal->column;
+               terminal->saved_attr = terminal->curr_attr;
+               terminal->saved_origin_mode = terminal->origin_mode;
+               break;
+       case '8':    /* DECRC */
+               terminal->row = terminal->saved_row;
+               terminal->column = terminal->saved_column;
+               terminal->curr_attr = terminal->saved_attr;
+               terminal->origin_mode = terminal->saved_origin_mode;
+               break;
        default:
                fprintf(stderr, "Unknown escape code: %c\n", code);
                break;
@@ -829,6 +1072,25 @@ handle_non_csi_escape(struct terminal *terminal, char code)
 static void
 handle_special_escape(struct terminal *terminal, char special, char code)
 {
+       int i, numChars;
+
+       if (special == '#') {
+               switch(code) {
+               case '8':
+                       /* fill with 'E', no cheap way to do this */
+                       memset(terminal->data, 0, terminal->data_pitch * terminal->height);
+                       numChars = terminal->width * terminal->height;
+                       for(i = 0; i < numChars; i++) {
+                               terminal->data[i].byte[0] = 'E';
+                       }
+                       break;
+               default:
+                       fprintf(stderr, "Unknown HASH escape #%c\n", code);
+                       break;
+               }
+       } else {
+               fprintf(stderr, "Unknown special escape %c%c\n", special, code);
+       }
 }
 
 static void
@@ -908,7 +1170,9 @@ handle_special_char(struct terminal *terminal, char c)
                terminal->column = 0;
                break;
        case '\n':
-               terminal->column = 0;
+               if (terminal->mode & MODE_LF_NEWLINE) {
+                       terminal->column = 0;
+               }
                /* fallthrough */
        case '\v':
        case '\f':
@@ -920,13 +1184,32 @@ handle_special_char(struct terminal *terminal, char c)
 
                break;
        case '\t':
-               memset(&row[terminal->column], ' ', (-terminal->column & 7) * sizeof(union utf8_char));
-               attr_init(&attr_row[terminal->column], terminal->curr_attr, -terminal->column & 7);
-               terminal->column = (terminal->column + 7) & ~7;
+               while (terminal->column < terminal->width) {
+                       if (terminal->tab_ruler[terminal->column]) break;
+                       row[terminal->column].byte[0] = ' ';
+                       row[terminal->column].byte[1] = '\0';
+                       attr_row[terminal->column] = terminal->curr_attr;
+                       terminal->column++;
+               }
+               if (terminal->column >= terminal->width) {
+                       terminal->column = terminal->width - 1;
+               }
+
                break;
        case '\b':
-               if (terminal->column > 0)
+               if (terminal->column >= terminal->width) {
+                       terminal->column = terminal->width - 2;
+               } else if (terminal->column > 0) {
                        terminal->column--;
+               } else if (terminal->mode & MODE_AUTOWRAP) {
+                       terminal->column = terminal->width - 1;
+                       terminal->row -= 1;
+                       if (terminal->row < terminal->margin_top) {
+                               terminal->row = terminal->margin_top;
+                               terminal_scroll(terminal, -1);
+                       }
+               }
+
                break;
        case '\a':
                /* Bell */
@@ -961,8 +1244,17 @@ handle_char(struct terminal *terminal, union utf8_char utf8)
        
        /* handle right margin effects */
        if (terminal->column >= terminal->width) {
-               terminal->column--;
-       }
+               if (terminal->mode & MODE_AUTOWRAP) {
+                       terminal->column = 0;
+                       terminal->row += 1;
+                       if (terminal->row > terminal->margin_bottom) {
+                               terminal->row = terminal->margin_bottom;
+                               terminal_scroll(terminal, +1);
+                       }
+               } else {
+                       terminal->column--;
+               }
+       }
        
        row = terminal_get_row(terminal, terminal->row);
        attr_row = terminal_get_attr_row(terminal, terminal->row);
@@ -1067,7 +1359,7 @@ key_handler(struct window *window, uint32_t key, uint32_t sym,
            uint32_t state, uint32_t modifiers, void *data)
 {
        struct terminal *terminal = data;
-       char ch[2];
+       char ch[MAX_RESPONSE];
        int len = 0;
 
        switch (sym) {
@@ -1085,7 +1377,6 @@ key_handler(struct window *window, uint32_t key, uint32_t sym,
        case XK_Tab:
        case XK_Linefeed:
        case XK_Clear:
-       case XK_Return:
        case XK_Pause:
        case XK_Scroll_Lock:
        case XK_Sys_Req:
@@ -1093,6 +1384,15 @@ key_handler(struct window *window, uint32_t key, uint32_t sym,
                ch[len++] = sym & 0x7f;
                break;
 
+       case XK_Return:
+               if (terminal->mode & MODE_LF_NEWLINE) {
+                       ch[len++] = 0x0D;
+                       ch[len++] = 0x0A;
+               } else {
+                       ch[len++] = 0x0D;
+               }
+               break;
+
        case XK_Shift_L:
        case XK_Shift_R:
        case XK_Control_L: