Allow negative numbers in CSI codes

kitty/cursor.c

@@ -47,7 +47,7 @@ cursor_reset_display_attrs(Cursor *self) {
 
 
 static inline void
-parse_color(unsigned int *params, unsigned int *i, unsigned int count, uint32_t *result) {
+parse_color(int *params, unsigned int *i, unsigned int count, uint32_t *result) {
     unsigned int attr;
     uint8_t r, g, b;
     if (*i < count) {
@@ -73,7 +73,7 @@ parse_color(unsigned int *params, unsigned int *i, unsigned int count, uint32_t
 
 
 void
-cursor_from_sgr(Cursor *self, unsigned int *params, unsigned int count) {
+cursor_from_sgr(Cursor *self, int *params, unsigned int count) {
 #define SET_COLOR(which) { parse_color(params, &i, count, &self->which); } break;
 START_ALLOW_CASE_RANGE
     unsigned int i = 0, attr;
@@ -90,7 +90,7 @@ START_ALLOW_CASE_RANGE
             case 3:
                 self->italic = true;  break;
             case 4:
-                if (i < count) { self->decoration = MIN(3u, params[i]); i++; }
+                if (i < count) { self->decoration = MIN(3, params[i]); i++; }
                 else self->decoration = 1;
                 break;
             case 7:
@@ -136,7 +136,7 @@ END_ALLOW_CASE_RANGE
 }
 
 void
-apply_sgr_to_cells(GPUCell *first_cell, unsigned int cell_count, unsigned int *params, unsigned int count) {
+apply_sgr_to_cells(GPUCell *first_cell, unsigned int cell_count, int *params, unsigned int count) {
 #define RANGE for(unsigned c = 0; c < cell_count; c++, cell++)
 #define SET(shift) RANGE { cell->attrs |= (1 << shift); } break;
 #define RESET(shift) RANGE { cell->attrs &= ~(1 << shift); } break;
@@ -161,7 +161,7 @@ apply_sgr_to_cells(GPUCell *first_cell, unsigned int cell_count, unsigned int *p
             case 3:
                 SET(ITALIC_SHIFT);
             case 4:
-                if (i < count) { uint8_t val = MIN(3u, params[i]); i++; SETM(val, DECORATION_MASK, DECORATION_SHIFT); }
+                if (i < count) { uint8_t val = MIN(3, params[i]); i++; SETM(val, DECORATION_MASK, DECORATION_SHIFT); }
                 else { SETM(1, DECORATION_MASK, DECORATION_SHIFT); }
             case 7:
                 SET(REVERSE_SHIFT);

kitty/data-types.h

@@ -299,8 +299,8 @@ void cursor_reset(Cursor*);
 Cursor* cursor_copy(Cursor*);
 void cursor_copy_to(Cursor *src, Cursor *dest);
 void cursor_reset_display_attrs(Cursor*);
-void cursor_from_sgr(Cursor *self, unsigned int *params, unsigned int count);
+void cursor_from_sgr(Cursor *self, int *params, unsigned int count);
-void apply_sgr_to_cells(GPUCell *first_cell, unsigned int cell_count, unsigned int *params, unsigned int count);
+void apply_sgr_to_cells(GPUCell *first_cell, unsigned int cell_count, int *params, unsigned int count);
 const char* cell_as_sgr(const GPUCell *, const GPUCell *);
 const char* cursor_as_sgr(const Cursor *);
 

kitty/parser.c

@@ -22,10 +22,14 @@ static uint64_t pow10_array[] = {
     1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000, 10000000000
 };
 
-static inline uint64_t
+static inline int64_t
-utoi(uint32_t *buf, unsigned int sz) {
+utoi(const uint32_t *buf, unsigned int sz) {
-    uint64_t ans = 0;
+    int64_t ans = 0;
-    uint32_t *p = buf;
+    const uint32_t *p = buf;
+    int mult = 1;
+    if (sz && *p == '-') {
+        mult = -1; p++; sz--;
+    }
     // Ignore leading zeros
     while(sz > 0) {
         if (*p == '0') { p++; sz--; }
@@ -36,7 +40,7 @@ utoi(uint32_t *buf, unsigned int sz) {
             ans += (p[i] - '0') * pow10_array[j];
         }
     }
-    return ans;
+    return ans * mult;
 }
 
 
@@ -79,12 +83,12 @@ _report_error(PyObject *dump_callback, const char *fmt, ...) {
 }
 
 static void
-_report_params(PyObject *dump_callback, const char *name, unsigned int *params, unsigned int count, Region *r) {
+_report_params(PyObject *dump_callback, const char *name, int *params, unsigned int count, Region *r) {
     static char buf[MAX_PARAMS*3] = {0};
     unsigned int i, p=0;
     if (r) p += snprintf(buf + p, sizeof(buf) - 2, "%u %u %u %u ", r->top, r->left, r->bottom, r->right);
     for(i = 0; i < count && p < MAX_PARAMS*3-20; i++) {
-        int n = snprintf(buf + p, MAX_PARAMS*3 - p, "%u ", params[i]);
+        int n = snprintf(buf + p, MAX_PARAMS*3 - p, "%i ", params[i]);
         if (n < 0) break;
         p += n;
     }
@@ -360,7 +364,8 @@ dispatch_osc(Screen *screen, PyObject DUMP_UNUSED *dump_callback) {
 #define END_DISPATCH Py_CLEAR(string); } PyErr_Clear(); break; }
 
     const unsigned int limit = screen->parser_buf_pos;
-    unsigned int code=0, i;
+    int code=0;
+    unsigned int i;
     for (i = 0; i < MIN(limit, 5u); i++) {
         if (screen->parser_buf[i] < '0' || screen->parser_buf[i] > '9') break;
     }
@@ -460,12 +465,12 @@ static inline void
 screen_tabn(Screen *s, unsigned int count) { for (index_type i=0; i < MAX(1u, count); i++) screen_tab(s); }
 
 static inline const char*
-repr_csi_params(unsigned int *params, unsigned int num_params) {
+repr_csi_params(int *params, unsigned int num_params) {
     if (!num_params) return "";
     static char buf[256];
     unsigned int pos = 0, i = 0;
     while (pos < 200 && i++ < num_params && sizeof(buf) > pos + 1) {
-        const char *fmt = i < num_params ? "%u, " : "%u";
+        const char *fmt = i < num_params ? "%i, " : "%i";
         int ret = snprintf(buf + pos, sizeof(buf) - pos - 1, fmt, params[i-1]);
         if (ret < 0) return "An error occurred formatting the params array";
         pos += ret;
@@ -478,7 +483,7 @@ repr_csi_params(unsigned int *params, unsigned int num_params) {
 static
 #endif
 void
-parse_sgr(Screen *screen, uint32_t *buf, unsigned int num, unsigned int *params, PyObject DUMP_UNUSED *dump_callback, const char *report_name DUMP_UNUSED, Region *region) {
+parse_sgr(Screen *screen, uint32_t *buf, unsigned int num, int *params, PyObject DUMP_UNUSED *dump_callback, const char *report_name DUMP_UNUSED, Region *region) {
     enum State { START, NORMAL, MULTIPLE, COLOR, COLOR1, COLOR3 };
     enum State state = START;
     unsigned int num_params, num_start, i;
@@ -606,7 +611,8 @@ parse_sgr(Screen *screen, uint32_t *buf, unsigned int num, unsigned int *params,
 
 static inline unsigned int
 parse_region(Region *r, uint32_t *buf, unsigned int num) {
-    unsigned int i, start, params[8] = {0}, num_params=0;
+    unsigned int i, start, num_params = 0;
+    int params[8] = {0};
     for (i=0, start=0; i < num && num_params < 4; i++) {
         switch(buf[i]) {
             IS_DIGIT
@@ -646,10 +652,17 @@ dispatch_csi(Screen *screen, PyObject DUMP_UNUSED *dump_callback) {
         break; \
     } \
 }
+#define NON_NEGATIVE_PARAM(x) { \
+    if (x < 0) { \
+        REPORT_ERROR("CSI code 0x%x is not allowed to have negative parameter (%d)", code, x); \
+        break; \
+    } \
+}
 
 #define CALL_CSI_HANDLER1(name, defval) \
     AT_MOST_ONE_PARAMETER; \
     p1 = num_params > 0 ? params[0] : defval; \
+    NON_NEGATIVE_PARAM(p1); \
     REPORT_COMMAND(name, p1); \
     name(screen, p1); \
     break;
@@ -657,6 +670,7 @@ dispatch_csi(Screen *screen, PyObject DUMP_UNUSED *dump_callback) {
 #define CALL_CSI_HANDLER1P(name, defval, qch) \
     AT_MOST_ONE_PARAMETER; \
     p1 = num_params > 0 ? params[0] : defval; \
+    NON_NEGATIVE_PARAM(p1); \
     private = start_modifier == qch; \
     REPORT_COMMAND(name, p1, private); \
     name(screen, p1, private); \
@@ -665,6 +679,7 @@ dispatch_csi(Screen *screen, PyObject DUMP_UNUSED *dump_callback) {
 #define CALL_CSI_HANDLER1S(name, defval) \
     AT_MOST_ONE_PARAMETER; \
     p1 = num_params > 0 ? params[0] : defval; \
+    NON_NEGATIVE_PARAM(p1); \
     REPORT_COMMAND(name, p1, start_modifier); \
     name(screen, p1, start_modifier); \
     break;
@@ -672,13 +687,20 @@ dispatch_csi(Screen *screen, PyObject DUMP_UNUSED *dump_callback) {
 #define CALL_CSI_HANDLER1M(name, defval) \
     AT_MOST_ONE_PARAMETER; \
     p1 = num_params > 0 ? params[0] : defval; \
+    NON_NEGATIVE_PARAM(p1); \
     REPORT_COMMAND(name, p1, end_modifier); \
     name(screen, p1, end_modifier); \
     break;
 
 #define CALL_CSI_HANDLER2(name, defval1, defval2) \
+    if (num_params > 2) { \
+        REPORT_ERROR("CSI code 0x%x has %u > 2 parameters", code, num_params); \
+        break; \
+    } \
     p1 = num_params > 0 ? params[0] : defval1; \
     p2 = num_params > 1 ? params[1] : defval2; \
+    NON_NEGATIVE_PARAM(p1); \
+    NON_NEGATIVE_PARAM(p2); \
     REPORT_COMMAND(name, p1, p2); \
     name(screen, p1, p2); \
     break;
@@ -701,8 +723,8 @@ dispatch_csi(Screen *screen, PyObject DUMP_UNUSED *dump_callback) {
 
     char start_modifier = 0, end_modifier = 0;
     uint32_t *buf = screen->parser_buf, code = screen->parser_buf[screen->parser_buf_pos];
-    unsigned int num = screen->parser_buf_pos, start, i, num_params=0, p1, p2;
+    unsigned int num = screen->parser_buf_pos, start, i, num_params=0;
-    static unsigned int params[MAX_PARAMS] = {0};
+    static int params[MAX_PARAMS] = {0}, p1, p2;
     bool private;
     if (buf[0] == '>' || buf[0] == '<' || buf[0] == '?' || buf[0] == '!' || buf[0] == '=') {
         start_modifier = (char)screen->parser_buf[0];
@@ -732,6 +754,12 @@ dispatch_csi(Screen *screen, PyObject DUMP_UNUSED *dump_callback) {
         switch(buf[i]) {
             IS_DIGIT
                 break;
+            case '-':
+                if (i > start) {
+                    REPORT_ERROR("CSI code can contain hyphens only at the start of numbers");
+                    return;
+                }
+                break;
             default:
                 if (i > start) params[num_params++] = utoi(buf + start, i - start);
                 else if (i == start && buf[i] == ';') params[num_params++] = 0;

kitty/screen.c

@@ -609,7 +609,7 @@ screen_alignment_display(Screen *self) {
 }
 
 void
-select_graphic_rendition(Screen *self, unsigned int *params, unsigned int count, Region *region_) {
+select_graphic_rendition(Screen *self, int *params, unsigned int count, Region *region_) {
     if (region_) {
         Region region = *region_;
         if (!region.top) region.top = 1;
@@ -2214,8 +2214,8 @@ reset_mode(Screen *self, PyObject *args) {
 
 static PyObject*
 _select_graphic_rendition(Screen *self, PyObject *args) {
-    unsigned int params[256] = {0};
+    int params[256] = {0};
-    for (int i = 0; i < PyTuple_GET_SIZE(args); i++) { params[i] = PyLong_AsUnsignedLong(PyTuple_GET_ITEM(args, i)); }
+    for (int i = 0; i < PyTuple_GET_SIZE(args); i++) { params[i] = PyLong_AsLong(PyTuple_GET_ITEM(args, i)); }
     select_graphic_rendition(self, params, PyTuple_GET_SIZE(args), NULL);
     Py_RETURN_NONE;
 }

kitty/screen.h

@@ -197,7 +197,7 @@ uint32_t* translation_table(uint32_t which);
 void screen_request_capabilities(Screen *, char, PyObject *);
 void screen_set_8bit_controls(Screen *, bool);
 void report_device_attributes(Screen *self, unsigned int UNUSED mode, char start_modifier);
-void select_graphic_rendition(Screen *self, unsigned int *params, unsigned int count, Region*);
+void select_graphic_rendition(Screen *self, int *params, unsigned int count, Region*);
 void report_device_status(Screen *self, unsigned int which, bool UNUSED);
 void report_mode_status(Screen *self, unsigned int which, bool);
 void screen_apply_selection(Screen *self, void *address, size_t size);

kitty_tests/parser.py

@@ -101,6 +101,9 @@ class TestParser(BaseTest):
         pb('x\033[2@y', 'x', ('screen_insert_characters', 2), 'y')
         self.ae(str(s.line(0)), 'xy bc')
         pb('x\033[2;7@y', 'x', ('CSI code 0x40 has 2 > 1 parameters',), 'y')
+        pb('x\033[2;-7@y', 'x', ('CSI code 0x40 has 2 > 1 parameters',), 'y')
+        pb('x\033[-2@y', 'x', ('CSI code 0x40 is not allowed to have negative parameter (-2)',), 'y')
+        pb('x\033[2-3@y', 'x', ('CSI code can contain hyphens only at the start of numbers',), 'y')
         pb('x\033[@y', 'x', ('screen_insert_characters', 1), 'y')
         pb('x\033[345@y', 'x', ('screen_insert_characters', 345), 'y')
         pb('x\033[345;@y', 'x', ('screen_insert_characters', 345), 'y')