terminal/screen: save state in separate object

Terminal state can be saved/restored by applications. To simplify our
internal handling, put all affected state into a separate object.
Especially with alternate screen buffers, this will simplify our code
significantly.

2 files changed, 175 insertions, 192 deletions

diff --git a/src/libsystemd-terminal/term-internal.h b/src/libsystemd-terminal/term-internal.h
index a023498b53..c78b9aa70a 100644
--- a/src/libsystemd-terminal/term-internal.h
+++ b/src/libsystemd-terminal/term-internal.h
@@ -37,6 +37,7 @@ typedef struct term_page term_page;
 typedef struct term_history term_history;
 
 typedef uint32_t term_charset[96];
+typedef struct term_state term_state;
 
 /*
  * Miscellaneous
@@ -586,11 +587,9 @@ enum {
         TERM_FLAG_HIDE_CURSOR                   = (1U << 1),    /* hide cursor caret (default: off) */
         TERM_FLAG_INHIBIT_TPARM                 = (1U << 2),    /* do not send TPARM unrequested (default: off) */
         TERM_FLAG_NEWLINE_MODE                  = (1U << 3),    /* perform carriage-return on line-feeds (default: off) */
-        TERM_FLAG_ORIGIN_MODE                   = (1U << 4),    /* in origin mode, the cursor is bound by the margins (default: off) */
-        TERM_FLAG_PENDING_WRAP                  = (1U << 5),    /* wrap-around is pending */
-        TERM_FLAG_AUTO_WRAP                     = (1U << 6),    /* auto-wrap mode causes line-wraps at line-ends (default: off) */
-        TERM_FLAG_KEYPAD_MODE                   = (1U << 7),    /* application-keypad mode (default: off) */
-        TERM_FLAG_CURSOR_KEYS                   = (1U << 8),    /* enable application cursor-keys (default: off) */
+        TERM_FLAG_PENDING_WRAP                  = (1U << 4),    /* wrap-around is pending */
+        TERM_FLAG_KEYPAD_MODE                   = (1U << 5),    /* application-keypad mode (default: off) */
+        TERM_FLAG_CURSOR_KEYS                   = (1U << 6),    /* enable application cursor-keys (default: off) */
 };
 
 enum {
@@ -600,6 +599,19 @@ enum {
         TERM_CONFORMANCE_LEVEL_CNT,
 };
 
+struct term_state {
+        unsigned int cursor_x;
+        unsigned int cursor_y;
+        term_attr attr;
+        term_charset **gl;
+        term_charset **gr;
+        term_charset **glt;
+        term_charset **grt;
+
+        bool auto_wrap : 1;
+        bool origin_mode : 1;
+};
+
 struct term_screen {
         unsigned long ref;
         term_age_t age;
@@ -623,15 +635,8 @@ struct term_screen {
 
         unsigned int flags;
         unsigned int conformance_level;
-        unsigned int cursor_x;
-        unsigned int cursor_y;
-        term_attr attr;
         term_attr default_attr;
 
-        term_charset **gl;
-        term_charset **gr;
-        term_charset **glt;
-        term_charset **grt;
         term_charset *g0;
         term_charset *g1;
         term_charset *g2;
@@ -639,14 +644,6 @@ struct term_screen {
 
         char *answerback;
 
-        struct {
-                unsigned int cursor_x;
-                unsigned int cursor_y;
-                term_attr attr;
-                term_charset **gl;
-                term_charset **gr;
-                term_charset **glt;
-                term_charset **grt;
-                unsigned int flags;
-        } saved;
+        term_state state;
+        term_state saved;
 };
diff --git a/src/libsystemd-terminal/term-screen.c b/src/libsystemd-terminal/term-screen.c
index 9026c25efe..c8a81658cb 100644
--- a/src/libsystemd-terminal/term-screen.c
+++ b/src/libsystemd-terminal/term-screen.c
@@ -70,18 +70,13 @@ int term_screen_new(term_screen **out, term_screen_write_fn write_fn, void *writ
         screen->cmd_fn_data = cmd_fn_data;
         screen->flags = TERM_FLAG_7BIT_MODE;
         screen->conformance_level = TERM_CONFORMANCE_LEVEL_VT400;
-        screen->gl = &screen->g0;
-        screen->gr = &screen->g1;
         screen->g0 = &term_unicode_lower;
         screen->g1 = &term_unicode_upper;
         screen->g2 = &term_unicode_lower;
         screen->g3 = &term_unicode_upper;
-
-        screen->saved.cursor_x = 0;
-        screen->saved.cursor_y = 0;
-        screen->saved.attr = screen->attr;
-        screen->saved.gl = screen->gl;
-        screen->saved.gr = screen->gr;
+        screen->state.gl = &screen->g0;
+        screen->state.gr = &screen->g1;
+        screen->saved = screen->state;
 
         r = term_page_new(&screen->page_main);
         if (r < 0)
@@ -224,7 +219,7 @@ static bool screen_tab_is_set(term_screen *screen, unsigned int pos) {
 static inline void screen_age_cursor(term_screen *screen) {
         term_cell *cell;
 
-        cell = term_page_get_cell(screen->page, screen->cursor_x, screen->cursor_y);
+        cell = term_page_get_cell(screen->page, screen->state.cursor_x, screen->state.cursor_y);
         if (cell)
                 cell->age = screen->age;
 }
@@ -237,21 +232,21 @@ static void screen_cursor_set(term_screen *screen, unsigned int x, unsigned int
         x = screen_clamp_x(screen, x);
         y = screen_clamp_y(screen, y);
 
-        if (x == screen->cursor_x && y == screen->cursor_y)
+        if (x == screen->state.cursor_x && y == screen->state.cursor_y)
                 return;
 
         if (!(screen->flags & TERM_FLAG_HIDE_CURSOR))
                 screen_age_cursor(screen);
 
-        screen->cursor_x = x;
-        screen->cursor_y = y;
+        screen->state.cursor_x = x;
+        screen->state.cursor_y = y;
 
         if (!(screen->flags & TERM_FLAG_HIDE_CURSOR))
                 screen_age_cursor(screen);
 }
 
 static void screen_cursor_set_rel(term_screen *screen, unsigned int x, unsigned int y) {
-        if (screen->flags & TERM_FLAG_ORIGIN_MODE) {
+        if (screen->state.origin_mode) {
                 x = screen_clamp_x(screen, x);
                 y = screen_clamp_x(screen, y) + screen->page->scroll_idx;
 
@@ -266,53 +261,53 @@ static void screen_cursor_set_rel(term_screen *screen, unsigned int x, unsigned
 }
 
 static void screen_cursor_left(term_screen *screen, unsigned int num) {
-        if (num > screen->cursor_x)
-                num = screen->cursor_x;
+        if (num > screen->state.cursor_x)
+                num = screen->state.cursor_x;
 
-        screen_cursor_set(screen, screen->cursor_x - num, screen->cursor_y);
+        screen_cursor_set(screen, screen->state.cursor_x - num, screen->state.cursor_y);
 }
 
 static void screen_cursor_left_tab(term_screen *screen, unsigned int num) {
         unsigned int i;
 
-        i = screen->cursor_x;
+        i = screen->state.cursor_x;
         while (i > 0 && num > 0) {
                 if (screen_tab_is_set(screen, --i))
                         --num;
         }
 
-        screen_cursor_set(screen, i, screen->cursor_y);
+        screen_cursor_set(screen, i, screen->state.cursor_y);
 }
 
 static void screen_cursor_right(term_screen *screen, unsigned int num) {
         if (num > screen->page->width)
                 num = screen->page->width;
 
-        screen_cursor_set(screen, screen->cursor_x + num, screen->cursor_y);
+        screen_cursor_set(screen, screen->state.cursor_x + num, screen->state.cursor_y);
 }
 
 static void screen_cursor_right_tab(term_screen *screen, unsigned int num) {
         unsigned int i;
 
-        i = screen->cursor_x;
+        i = screen->state.cursor_x;
         while (i + 1 < screen->page->width && num > 0) {
                 if (screen_tab_is_set(screen, ++i))
                         --num;
         }
 
-        screen_cursor_set(screen, i, screen->cursor_y);
+        screen_cursor_set(screen, i, screen->state.cursor_y);
 }
 
 static void screen_cursor_up(term_screen *screen, unsigned int num, bool scroll) {
         unsigned int max;
 
-        if (screen->cursor_y < screen->page->scroll_idx) {
-                if (num > screen->cursor_y)
-                        num = screen->cursor_y;
+        if (screen->state.cursor_y < screen->page->scroll_idx) {
+                if (num > screen->state.cursor_y)
+                        num = screen->state.cursor_y;
 
-                screen_cursor_set(screen, screen->cursor_x, screen->cursor_y - num);
+                screen_cursor_set(screen, screen->state.cursor_x, screen->state.cursor_y - num);
         } else {
-                max = screen->cursor_y - screen->page->scroll_idx;
+                max = screen->state.cursor_y - screen->page->scroll_idx;
                 if (num > max) {
                         if (num < 1)
                                 return;
@@ -321,14 +316,14 @@ static void screen_cursor_up(term_screen *screen, unsigned int num, bool scroll)
                                 screen_age_cursor(screen);
 
                         if (scroll)
-                                term_page_scroll_down(screen->page, num - max, &screen->attr, screen->age, NULL);
+                                term_page_scroll_down(screen->page, num - max, &screen->state.attr, screen->age, NULL);
 
-                        screen->cursor_y = screen->page->scroll_idx;
+                        screen->state.cursor_y = screen->page->scroll_idx;
 
                         if (!(screen->flags & TERM_FLAG_HIDE_CURSOR))
                                 screen_age_cursor(screen);
                 } else {
-                        screen_cursor_set(screen, screen->cursor_x, screen->cursor_y - num);
+                        screen_cursor_set(screen, screen->state.cursor_x, screen->state.cursor_y - num);
                 }
         }
 }
@@ -336,13 +331,13 @@ static void screen_cursor_up(term_screen *screen, unsigned int num, bool scroll)
 static void screen_cursor_down(term_screen *screen, unsigned int num, bool scroll) {
         unsigned int max;
 
-        if (screen->cursor_y >= screen->page->scroll_idx + screen->page->scroll_num) {
+        if (screen->state.cursor_y >= screen->page->scroll_idx + screen->page->scroll_num) {
                 if (num > screen->page->height)
                         num = screen->page->height;
 
-                screen_cursor_set(screen, screen->cursor_x, screen->cursor_y - num);
+                screen_cursor_set(screen, screen->state.cursor_x, screen->state.cursor_y - num);
         } else {
-                max = screen->page->scroll_idx + screen->page->scroll_num - 1 - screen->cursor_y;
+                max = screen->page->scroll_idx + screen->page->scroll_num - 1 - screen->state.cursor_y;
                 if (num > max) {
                         if (num < 1)
                                 return;
@@ -351,18 +346,27 @@ static void screen_cursor_down(term_screen *screen, unsigned int num, bool scrol
                                 screen_age_cursor(screen);
 
                         if (scroll)
-                                term_page_scroll_up(screen->page, num - max, &screen->attr, screen->age, screen->history);
+                                term_page_scroll_up(screen->page, num - max, &screen->state.attr, screen->age, screen->history);
 
-                        screen->cursor_y = screen->page->scroll_idx + screen->page->scroll_num - 1;
+                        screen->state.cursor_y = screen->page->scroll_idx + screen->page->scroll_num - 1;
 
                         if (!(screen->flags & TERM_FLAG_HIDE_CURSOR))
                                 screen_age_cursor(screen);
                 } else {
-                        screen_cursor_set(screen, screen->cursor_x, screen->cursor_y + num);
+                        screen_cursor_set(screen, screen->state.cursor_x, screen->state.cursor_y + num);
                 }
         }
 }
 
+static void screen_save_state(term_screen *screen, term_state *where) {
+        *where = screen->state;
+}
+
+static void screen_restore_state(term_screen *screen, term_state *from) {
+        screen_cursor_set(screen, from->cursor_x, from->cursor_y);
+        screen->state = *from;
+}
+
 static inline void set_reset(term_screen *screen, unsigned int flag, bool set) {
         if (set)
                 screen->flags |= flag;
@@ -388,7 +392,7 @@ static void screen_mode_change(term_screen *screen, unsigned int mode, bool dec,
                          * DECOM: origin-mode
                          * TODO
                          */
-                        set_reset(screen, TERM_FLAG_ORIGIN_MODE, set);
+                        screen->state.origin_mode = set;
                 }
 
                 break;
@@ -398,7 +402,7 @@ static void screen_mode_change(term_screen *screen, unsigned int mode, bool dec,
                          * DECAWN: auto-wrap mode
                          * TODO
                          */
-                        set_reset(screen, TERM_FLAG_AUTO_WRAP, set);
+                        screen->state.auto_wrap = set;
                 }
 
                 break;
@@ -435,19 +439,19 @@ static uint32_t screen_map(term_screen *screen, uint32_t val) {
          * identity. */
         switch (val) {
         case 33 ... 126:
-                if (screen->glt) {
-                        nval = (**screen->glt)[val - 32];
-                        screen->glt = NULL;
+                if (screen->state.glt) {
+                        nval = (**screen->state.glt)[val - 32];
+                        screen->state.glt = NULL;
                 } else {
-                        nval = (**screen->gl)[val - 32];
+                        nval = (**screen->state.gl)[val - 32];
                 }
                 break;
         case 160 ... 255:
-                if (screen->grt) {
-                        nval = (**screen->grt)[val - 160];
-                        screen->grt = NULL;
+                if (screen->state.grt) {
+                        nval = (**screen->state.grt)[val - 160];
+                        screen->state.grt = NULL;
                 } else {
-                        nval = (**screen->gr)[val - 160];
+                        nval = (**screen->state.gr)[val - 160];
                 }
                 break;
         }
@@ -471,20 +475,20 @@ static int screen_GRAPHIC(term_screen *screen, const term_seq *seq) {
         term_char_t ch = TERM_CHAR_NULL;
         uint32_t c;
 
-        if (screen->cursor_x + 1 == screen->page->width
+        if (screen->state.cursor_x + 1 == screen->page->width
             && screen->flags & TERM_FLAG_PENDING_WRAP
-            && screen->flags & TERM_FLAG_AUTO_WRAP) {
+            && screen->state.auto_wrap) {
                 screen_cursor_down(screen, 1, true);
-                screen_cursor_set(screen, 0, screen->cursor_y);
+                screen_cursor_set(screen, 0, screen->state.cursor_y);
         }
 
         screen_cursor_clear_wrap(screen);
 
         c = screen_map(screen, seq->terminator);
         ch = term_char_merge(ch, screen_map(screen, c));
-        term_page_write(screen->page, screen->cursor_x, screen->cursor_y, ch, 1, &screen->attr, screen->age, false);
+        term_page_write(screen->page, screen->state.cursor_x, screen->state.cursor_y, ch, 1, &screen->state.attr, screen->age, false);
 
-        if (screen->cursor_x + 1 == screen->page->width)
+        if (screen->state.cursor_x + 1 == screen->page->width)
                 screen->flags |= TERM_FLAG_PENDING_WRAP;
         else
                 screen_cursor_right(screen, 1);
@@ -556,7 +560,7 @@ static int screen_CHA(term_screen *screen, const term_seq *seq) {
                 pos = seq->args[0];
 
         screen_cursor_clear_wrap(screen);
-        screen_cursor_set(screen, pos - 1, screen->cursor_y);
+        screen_cursor_set(screen, pos - 1, screen->state.cursor_y);
 
         return 0;
 }
@@ -635,7 +639,7 @@ static int screen_CR(term_screen *screen, const term_seq *seq) {
          */
 
         screen_cursor_clear_wrap(screen);
-        screen_cursor_set(screen, 0, screen->cursor_y);
+        screen_cursor_set(screen, 0, screen->state.cursor_y);
 
         return 0;
 }
@@ -901,7 +905,7 @@ static int screen_DCH(term_screen *screen, const term_seq *seq) {
                 num = seq->args[0];
 
         screen_cursor_clear_wrap(screen);
-        term_page_delete_cells(screen->page, screen->cursor_x, screen->cursor_y, num, &screen->attr, screen->age);
+        term_page_delete_cells(screen->page, screen->state.cursor_x, screen->state.cursor_y, num, &screen->state.attr, screen->age);
 
         return 0;
 }
@@ -1254,14 +1258,7 @@ static int screen_DECRC(term_screen *screen, const term_seq *seq) {
          * state for the main display and the status line.
          */
 
-        screen->attr = screen->saved.attr;
-        screen->gl = screen->saved.gl;
-        screen->gr = screen->saved.gr;
-        screen->glt = screen->saved.glt;
-        screen->grt = screen->saved.grt;
-        set_reset(screen, TERM_FLAG_AUTO_WRAP, screen->saved.flags & TERM_FLAG_AUTO_WRAP);
-        set_reset(screen, TERM_FLAG_ORIGIN_MODE, screen->saved.flags & TERM_FLAG_ORIGIN_MODE);
-        screen_cursor_set(screen, screen->saved.cursor_x, screen->saved.cursor_y);
+        screen_restore_state(screen, &screen->saved);
 
         return 0;
 }
@@ -1468,15 +1465,7 @@ static int screen_DECSC(term_screen *screen, const term_seq *seq) {
          *   * Any single shift 2 (SS2) or single shift 3 (SS3) functions sent
          */
 
-        screen->saved.cursor_x = screen->cursor_x;
-        screen->saved.cursor_y = screen->cursor_y;
-        screen->saved.attr = screen->attr;
-        screen->saved.gl = screen->gl;
-        screen->saved.gr = screen->gr;
-        screen->saved.glt = screen->glt;
-        screen->saved.grt = screen->grt;
-        screen->saved.flags = screen->flags & (TERM_FLAG_AUTO_WRAP
-                                               | TERM_FLAG_ORIGIN_MODE);
+        screen_save_state(screen, &screen->saved);
 
         return 0;
 }
@@ -1503,10 +1492,10 @@ static int screen_DECSCA(term_screen *screen, const term_seq *seq) {
         switch (mode) {
         case 0:
         case 2:
-                screen->attr.protect = 0;
+                screen->state.attr.protect = 0;
                 break;
         case 1:
-                screen->attr.protect = 1;
+                screen->state.attr.protect = 1;
                 break;
         }
 
@@ -1671,21 +1660,21 @@ static int screen_DECSED(term_screen *screen, const term_seq *seq) {
         switch (mode) {
         case 0:
                 term_page_erase(screen->page,
-                                screen->cursor_x, screen->cursor_y,
+                                screen->state.cursor_x, screen->state.cursor_y,
                                 screen->page->width, screen->page->height,
-                                &screen->attr, screen->age, true);
+                                &screen->state.attr, screen->age, true);
                 break;
         case 1:
                 term_page_erase(screen->page,
                                 0, 0,
-                                screen->cursor_x, screen->cursor_y,
-                                &screen->attr, screen->age, true);
+                                screen->state.cursor_x, screen->state.cursor_y,
+                                &screen->state.attr, screen->age, true);
                 break;
         case 2:
                 term_page_erase(screen->page,
                                 0, 0,
                                 screen->page->width, screen->page->height,
-                                &screen->attr, screen->age, true);
+                                &screen->state.attr, screen->age, true);
                 break;
         }
 
@@ -1717,21 +1706,21 @@ static int screen_DECSEL(term_screen *screen, const term_seq *seq) {
         switch (mode) {
         case 0:
                 term_page_erase(screen->page,
-                                screen->cursor_x, screen->cursor_y,
-                                screen->page->width, screen->cursor_y,
-                                &screen->attr, screen->age, true);
+                                screen->state.cursor_x, screen->state.cursor_y,
+                                screen->page->width, screen->state.cursor_y,
+                                &screen->state.attr, screen->age, true);
                 break;
         case 1:
                 term_page_erase(screen->page,
-                                0, screen->cursor_y,
-                                screen->cursor_x, screen->cursor_y,
-                                &screen->attr, screen->age, true);
+                                0, screen->state.cursor_y,
+                                screen->state.cursor_x, screen->state.cursor_y,
+                                &screen->state.attr, screen->age, true);
                 break;
         case 2:
                 term_page_erase(screen->page,
-                                0, screen->cursor_y,
-                                screen->page->width, screen->cursor_y,
-                                &screen->attr, screen->age, true);
+                                0, screen->state.cursor_y,
+                                screen->page->width, screen->state.cursor_y,
+                                &screen->state.attr, screen->age, true);
                 break;
         }
 
@@ -2078,7 +2067,7 @@ static int screen_DL(term_screen *screen, const term_seq *seq) {
         if (seq->args[0] > 0)
                 num = seq->args[0];
 
-        term_page_delete_lines(screen->page, screen->cursor_y, num, &screen->attr, screen->age);
+        term_page_delete_lines(screen->page, screen->state.cursor_y, num, &screen->state.attr, screen->age);
 
         return 0;
 }
@@ -2123,9 +2112,9 @@ static int screen_ECH(term_screen *screen, const term_seq *seq) {
                 num = seq->args[0];
 
         term_page_erase(screen->page,
-                        screen->cursor_x, screen->cursor_y,
-                        screen->cursor_x + num, screen->cursor_y,
-                        &screen->attr, screen->age, false);
+                        screen->state.cursor_x, screen->state.cursor_y,
+                        screen->state.cursor_x + num, screen->state.cursor_y,
+                        &screen->state.attr, screen->age, false);
 
         return 0;
 }
@@ -2154,21 +2143,21 @@ static int screen_ED(term_screen *screen, const term_seq *seq) {
         switch (mode) {
         case 0:
                 term_page_erase(screen->page,
-                                screen->cursor_x, screen->cursor_y,
+                                screen->state.cursor_x, screen->state.cursor_y,
                                 screen->page->width, screen->page->height,
-                                &screen->attr, screen->age, false);
+                                &screen->state.attr, screen->age, false);
                 break;
         case 1:
                 term_page_erase(screen->page,
                                 0, 0,
-                                screen->cursor_x, screen->cursor_y,
-                                &screen->attr, screen->age, false);
+                                screen->state.cursor_x, screen->state.cursor_y,
+                                &screen->state.attr, screen->age, false);
                 break;
         case 2:
                 term_page_erase(screen->page,
                                 0, 0,
                                 screen->page->width, screen->page->height,
-                                &screen->attr, screen->age, false);
+                                &screen->state.attr, screen->age, false);
                 break;
         }
 
@@ -2198,21 +2187,21 @@ static int screen_EL(term_screen *screen, const term_seq *seq) {
         switch (mode) {
         case 0:
                 term_page_erase(screen->page,
-                                screen->cursor_x, screen->cursor_y,
-                                screen->page->width, screen->cursor_y,
-                                &screen->attr, screen->age, false);
+                                screen->state.cursor_x, screen->state.cursor_y,
+                                screen->page->width, screen->state.cursor_y,
+                                &screen->state.attr, screen->age, false);
                 break;
         case 1:
                 term_page_erase(screen->page,
-                                0, screen->cursor_y,
-                                screen->cursor_x, screen->cursor_y,
-                                &screen->attr, screen->age, false);
+                                0, screen->state.cursor_y,
+                                screen->state.cursor_x, screen->state.cursor_y,
+                                &screen->state.attr, screen->age, false);
                 break;
         case 2:
                 term_page_erase(screen->page,
-                                0, screen->cursor_y,
-                                screen->page->width, screen->cursor_y,
-                                &screen->attr, screen->age, false);
+                                0, screen->state.cursor_y,
+                                screen->page->width, screen->state.cursor_y,
+                                &screen->state.attr, screen->age, false);
                 break;
         }
 
@@ -2271,7 +2260,7 @@ static int screen_HPA(term_screen *screen, const term_seq *seq) {
                 num = seq->args[0];
 
         screen_cursor_clear_wrap(screen);
-        screen_cursor_set(screen, num - 1, screen->cursor_y);
+        screen_cursor_set(screen, num - 1, screen->state.cursor_y);
 
         return 0;
 }
@@ -2327,7 +2316,7 @@ static int screen_HTS(term_screen *screen, const term_seq *seq) {
 
         unsigned int pos;
 
-        pos = screen->cursor_x;
+        pos = screen->state.cursor_x;
         if (screen->page->width > 0)
                 screen->tabs[pos / 8] |= 1U << (pos % 8);
 
@@ -2372,7 +2361,7 @@ static int screen_ICH(term_screen *screen, const term_seq *seq) {
                 num = seq->args[0];
 
         screen_cursor_clear_wrap(screen);
-        term_page_insert_cells(screen->page, screen->cursor_x, screen->cursor_y, num, &screen->attr, screen->age);
+        term_page_insert_cells(screen->page, screen->state.cursor_x, screen->state.cursor_y, num, &screen->state.attr, screen->age);
 
         return 0;
 }
@@ -2398,7 +2387,7 @@ static int screen_IL(term_screen *screen, const term_seq *seq) {
                 num = seq->args[0];
 
         screen_cursor_clear_wrap(screen);
-        term_page_insert_lines(screen->page, screen->cursor_y, num, &screen->attr, screen->age);
+        term_page_insert_lines(screen->page, screen->state.cursor_y, num, &screen->state.attr, screen->age);
 
         return 0;
 }
@@ -2424,7 +2413,7 @@ static int screen_LF(term_screen *screen, const term_seq *seq) {
 
         screen_cursor_down(screen, 1, true);
         if (screen->flags & TERM_FLAG_NEWLINE_MODE)
-                screen_cursor_left(screen, screen->cursor_x);
+                screen_cursor_left(screen, screen->state.cursor_x);
 
         return 0;
 }
@@ -2435,7 +2424,7 @@ static int screen_LS1R(term_screen *screen, const term_seq *seq) {
          * Map G1 into GR.
          */
 
-        screen->gr = &screen->g1;
+        screen->state.gr = &screen->g1;
 
         return 0;
 }
@@ -2446,7 +2435,7 @@ static int screen_LS2(term_screen *screen, const term_seq *seq) {
          * Map G2 into GL.
          */
 
-        screen->gl = &screen->g2;
+        screen->state.gl = &screen->g2;
 
         return 0;
 }
@@ -2457,7 +2446,7 @@ static int screen_LS2R(term_screen *screen, const term_seq *seq) {
          * Map G2 into GR.
          */
 
-        screen->gr = &screen->g2;
+        screen->state.gr = &screen->g2;
 
         return 0;
 }
@@ -2468,7 +2457,7 @@ static int screen_LS3(term_screen *screen, const term_seq *seq) {
          * Map G3 into GL.
          */
 
-        screen->gl = &screen->g3;
+        screen->state.gl = &screen->g3;
 
         return 0;
 }
@@ -2479,7 +2468,7 @@ static int screen_LS3R(term_screen *screen, const term_seq *seq) {
          * Map G3 into GR.
          */
 
-        screen->gr = &screen->g3;
+        screen->state.gr = &screen->g3;
 
         return 0;
 }
@@ -2513,7 +2502,7 @@ static int screen_NEL(term_screen *screen, const term_seq *seq) {
 
         screen_cursor_clear_wrap(screen);
         screen_cursor_down(screen, 1, true);
-        screen_cursor_set(screen, 0, screen->cursor_y);
+        screen_cursor_set(screen, 0, screen->state.cursor_y);
 
         return 0;
 }
@@ -2834,7 +2823,7 @@ static int screen_SD(term_screen *screen, const term_seq *seq) {
         if (seq->args[0] > 0)
                 num = seq->args[0];
 
-        term_page_scroll_down(screen->page, num, &screen->attr, screen->age, NULL);
+        term_page_scroll_down(screen->page, num, &screen->state.attr, screen->age, NULL);
 
         return 0;
 }
@@ -2849,7 +2838,7 @@ static int screen_SGR(term_screen *screen, const term_seq *seq) {
         int v;
 
         if (seq->n_args < 1) {
-                zero(screen->attr);
+                zero(screen->state.attr);
                 return 0;
         }
 
@@ -2857,67 +2846,67 @@ static int screen_SGR(term_screen *screen, const term_seq *seq) {
                 v = seq->args[i];
                 switch (v) {
                 case 1:
-                        screen->attr.bold = 1;
+                        screen->state.attr.bold = 1;
                         break;
                 case 3:
-                        screen->attr.italic = 1;
+                        screen->state.attr.italic = 1;
                         break;
                 case 4:
-                        screen->attr.underline = 1;
+                        screen->state.attr.underline = 1;
                         break;
                 case 5:
-                        screen->attr.blink = 1;
+                        screen->state.attr.blink = 1;
                         break;
                 case 7:
-                        screen->attr.inverse = 1;
+                        screen->state.attr.inverse = 1;
                         break;
                 case 8:
-                        screen->attr.hidden = 1;
+                        screen->state.attr.hidden = 1;
                         break;
                 case 22:
-                        screen->attr.bold = 0;
+                        screen->state.attr.bold = 0;
                         break;
                 case 23:
-                        screen->attr.italic = 0;
+                        screen->state.attr.italic = 0;
                         break;
                 case 24:
-                        screen->attr.underline = 0;
+                        screen->state.attr.underline = 0;
                         break;
                 case 25:
-                        screen->attr.blink = 0;
+                        screen->state.attr.blink = 0;
                         break;
                 case 27:
-                        screen->attr.inverse = 0;
+                        screen->state.attr.inverse = 0;
                         break;
                 case 28:
-                        screen->attr.hidden = 0;
+                        screen->state.attr.hidden = 0;
                         break;
                 case 30 ... 37:
-                        screen->attr.fg.ccode = v - 30 + TERM_CCODE_BLACK;
+                        screen->state.attr.fg.ccode = v - 30 + TERM_CCODE_BLACK;
                         break;
                 case 39:
-                        screen->attr.fg.ccode = 0;
+                        screen->state.attr.fg.ccode = 0;
                         break;
                 case 40 ... 47:
-                        screen->attr.bg.ccode = v - 40 + TERM_CCODE_BLACK;
+                        screen->state.attr.bg.ccode = v - 40 + TERM_CCODE_BLACK;
                         break;
                 case 49:
-                        screen->attr.bg.ccode = 0;
+                        screen->state.attr.bg.ccode = 0;
                         break;
                 case 90 ... 97:
-                        screen->attr.fg.ccode = v - 90 + TERM_CCODE_LIGHT_BLACK;
+                        screen->state.attr.fg.ccode = v - 90 + TERM_CCODE_LIGHT_BLACK;
                         break;
                 case 100 ... 107:
-                        screen->attr.bg.ccode = v - 100 + TERM_CCODE_LIGHT_BLACK;
+                        screen->state.attr.bg.ccode = v - 100 + TERM_CCODE_LIGHT_BLACK;
                         break;
                 case 38:
                         /* fallthrough */
                 case 48:
 
                         if (v == 38)
-                                dst = &screen->attr.fg;
+                                dst = &screen->state.attr.fg;
                         else
-                                dst = &screen->attr.bg;
+                                dst = &screen->state.attr.bg;
 
                         ++i;
                         if (i >= seq->n_args)
@@ -2955,7 +2944,7 @@ static int screen_SGR(term_screen *screen, const term_seq *seq) {
                 case -1:
                         /* fallthrough */
                 case 0:
-                        zero(screen->attr);
+                        zero(screen->state.attr);
                         break;
                 }
         }
@@ -2969,7 +2958,7 @@ static int screen_SI(term_screen *screen, const term_seq *seq) {
          * Map G0 into GL.
          */
 
-        screen->gl = &screen->g0;
+        screen->state.gl = &screen->g0;
 
         return 0;
 }
@@ -3009,7 +2998,7 @@ static int screen_SO(term_screen *screen, const term_seq *seq) {
          * Map G1 into GL.
          */
 
-        screen->gl = &screen->g1;
+        screen->state.gl = &screen->g1;
 
         return 0;
 }
@@ -3030,7 +3019,7 @@ static int screen_SS2(term_screen *screen, const term_seq *seq) {
          * Temporarily map G2 into GL for the next graphics character.
          */
 
-        screen->glt = &screen->g2;
+        screen->state.glt = &screen->g2;
 
         return 0;
 }
@@ -3041,7 +3030,7 @@ static int screen_SS3(term_screen *screen, const term_seq *seq) {
          * Temporarily map G3 into GL for the next graphics character
          */
 
-        screen->glt = &screen->g3;
+        screen->state.glt = &screen->g3;
 
         return 0;
 }
@@ -3077,7 +3066,7 @@ static int screen_SU(term_screen *screen, const term_seq *seq) {
         if (seq->args[0] > 0)
                 num = seq->args[0];
 
-        term_page_scroll_up(screen->page, num, &screen->attr, screen->age, screen->history);
+        term_page_scroll_up(screen->page, num, &screen->state.attr, screen->age, screen->history);
 
         return 0;
 }
@@ -3116,7 +3105,7 @@ static int screen_TBC(term_screen *screen, const term_seq *seq) {
 
         switch (mode) {
         case 0:
-                pos = screen->cursor_x;
+                pos = screen->state.cursor_x;
                 if (screen->page->width > 0)
                         screen->tabs[pos / 8] &= ~(1U << (pos % 8));
                 break;
@@ -3147,7 +3136,7 @@ static int screen_VPA(term_screen *screen, const term_seq *seq) {
                 pos = seq->args[0];
 
         screen_cursor_clear_wrap(screen);
-        screen_cursor_set_rel(screen, screen->cursor_x, pos - 1);
+        screen_cursor_set_rel(screen, screen->state.cursor_x, pos - 1);
 
         return 0;
 }
@@ -4104,11 +4093,11 @@ int term_screen_resize(term_screen *screen, unsigned int x, unsigned int y) {
 
         assert_return(screen, -EINVAL);
 
-        r = term_page_reserve(screen->page_main, x, y, &screen->attr, screen->age);
+        r = term_page_reserve(screen->page_main, x, y, &screen->state.attr, screen->age);
         if (r < 0)
                 return r;
 
-        r = term_page_reserve(screen->page_alt, x, y, &screen->attr, screen->age);
+        r = term_page_reserve(screen->page_alt, x, y, &screen->state.attr, screen->age);
         if (r < 0)
                 return r;
 
@@ -4124,11 +4113,11 @@ int term_screen_resize(term_screen *screen, unsigned int x, unsigned int y) {
         for (i = (screen->page->width + 7) / 8 * 8; i < x; i += 8)
                 screen->tabs[i / 8] = 0x1;
 
-        term_page_resize(screen->page_main, x, y, &screen->attr, screen->age, screen->history);
-        term_page_resize(screen->page_alt, x, y, &screen->attr, screen->age, NULL);
+        term_page_resize(screen->page_main, x, y, &screen->state.attr, screen->age, screen->history);
+        term_page_resize(screen->page_alt, x, y, &screen->state.attr, screen->age, NULL);
 
-        screen->cursor_x = screen_clamp_x(screen, screen->cursor_x);
-        screen->cursor_y = screen_clamp_x(screen, screen->cursor_y);
+        screen->state.cursor_x = screen_clamp_x(screen, screen->state.cursor_x);
+        screen->state.cursor_y = screen_clamp_x(screen, screen->state.cursor_y);
         screen_cursor_clear_wrap(screen);
 
         return 0;
@@ -4139,29 +4128,26 @@ void term_screen_soft_reset(term_screen *screen) {
 
         assert(screen);
 
-        screen->gl = &screen->g0;
-        screen->gr = &screen->g1;
-        screen->glt = NULL;
-        screen->grt = NULL;
         screen->g0 = &term_unicode_lower;
         screen->g1 = &term_unicode_upper;
         screen->g2 = &term_unicode_lower;
         screen->g3 = &term_unicode_upper;
+        screen->state.attr = screen->default_attr;
+        screen->state.gl = &screen->g0;
+        screen->state.gr = &screen->g1;
+        screen->state.glt = NULL;
+        screen->state.grt = NULL;
+        screen->state.auto_wrap = 0;
+        screen->state.origin_mode = 0;
+
+        screen->saved = screen->state;
+        screen->saved.cursor_x = 0;
+        screen->saved.cursor_y = 0;
 
         screen->page = screen->page_main;
         screen->history = screen->history_main;
         screen->flags = TERM_FLAG_7BIT_MODE;
         screen->conformance_level = TERM_CONFORMANCE_LEVEL_VT400;
-        screen->attr = screen->default_attr;
-
-        screen->saved.cursor_x = 0;
-        screen->saved.cursor_y = 0;
-        screen->saved.attr = screen->attr;
-        screen->saved.gl = screen->gl;
-        screen->saved.gr = screen->gr;
-        screen->saved.glt = NULL;
-        screen->saved.grt = NULL;
-        screen->flags = 0;
 
         for (i = 0; i < screen->page->width; i += 8)
                 screen->tabs[i / 8] = 0x1;
@@ -4175,10 +4161,10 @@ void term_screen_hard_reset(term_screen *screen) {
 
         term_screen_soft_reset(screen);
         zero(screen->utf8);
-        screen->cursor_x = 0;
-        screen->cursor_y = 0;
-        term_page_erase(screen->page_main, 0, 0, screen->page->width, screen->page->height, &screen->attr, screen->age, false);
-        term_page_erase(screen->page_alt, 0, 0, screen->page->width, screen->page->height, &screen->attr, screen->age, false);
+        screen->state.cursor_x = 0;
+        screen->state.cursor_y = 0;
+        term_page_erase(screen->page_main, 0, 0, screen->page->width, screen->page->height, &screen->state.attr, screen->age, false);
+        term_page_erase(screen->page_alt, 0, 0, screen->page->width, screen->page->height, &screen->state.attr, screen->age, false);
 }
 
 int term_screen_set_answerback(term_screen *screen, const char *answerback) {
@@ -4248,7 +4234,7 @@ int term_screen_draw(term_screen *screen,
                         cw = MAX(cell->cwidth, 1U);
 
                         attr = cell->attr;
-                        if (i == screen->cursor_x && j == screen->cursor_y &&
+                        if (i == screen->state.cursor_x && j == screen->state.cursor_y &&
                             !(screen->flags & TERM_FLAG_HIDE_CURSOR))
                                 attr.inverse ^= 1;