1 files changed, 335 insertions, 0 deletions
diff --git a/src/nvim/vterm/vterm.c b/src/nvim/vterm/vterm.c
new file mode 100644
index 0000000000..76d5dc3808
--- /dev/null
+++ b/src/nvim/vterm/vterm.c
@@ -0,0 +1,335 @@
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "auto/config.h"
+#include "nvim/memory.h"
+#include "nvim/vterm/screen.h"
+#include "nvim/vterm/state.h"
+#include "nvim/vterm/vterm.h"
+#include "nvim/vterm/vterm_internal_defs.h"
+
+#ifdef INCLUDE_GENERATED_DECLARATIONS
+# include "vterm/vterm.c.generated.h"
+#endif
+
+// *****************
+// * API functions *
+// *****************
+
+static void *default_malloc(size_t size, void *allocdata)
+{
+  void *ptr = xmalloc(size);
+  if (ptr) {
+    memset(ptr, 0, size);
+  }
+  return ptr;
+}
+
+static void default_free(void *ptr, void *allocdata)
+{
+  xfree(ptr);
+}
+
+static VTermAllocatorFunctions default_allocator = {
+  .malloc = &default_malloc,
+  .free = &default_free,
+};
+
+/// Convenient shortcut for default cases
+VTerm *vterm_new(int rows, int cols)
+{
+  return vterm_build(&(const struct VTermBuilder){
+    .rows = rows,
+    .cols = cols,
+  });
+}
+
+// A handy macro for defaulting values out of builder fields
+#define DEFAULT(v, def)  ((v) ? (v) : (def))
+
+VTerm *vterm_build(const struct VTermBuilder *builder)
+{
+  const VTermAllocatorFunctions *allocator = DEFAULT(builder->allocator, &default_allocator);
+
+  // Need to bootstrap using the allocator function directly
+  VTerm *vt = (*allocator->malloc)(sizeof(VTerm), builder->allocdata);
+
+  vt->allocator = allocator;
+  vt->allocdata = builder->allocdata;
+
+  vt->rows = builder->rows;
+  vt->cols = builder->cols;
+
+  vt->parser.state = NORMAL;
+
+  vt->parser.callbacks = NULL;
+  vt->parser.cbdata = NULL;
+
+  vt->parser.emit_nul = false;
+
+  vt->outfunc = NULL;
+  vt->outdata = NULL;
+
+  vt->outbuffer_len = DEFAULT(builder->outbuffer_len, 4096);
+  vt->outbuffer_cur = 0;
+  vt->outbuffer = vterm_allocator_malloc(vt, vt->outbuffer_len);
+
+  vt->tmpbuffer_len = DEFAULT(builder->tmpbuffer_len, 4096);
+  vt->tmpbuffer = vterm_allocator_malloc(vt, vt->tmpbuffer_len);
+
+  return vt;
+}
+
+void vterm_free(VTerm *vt)
+{
+  if (vt->screen) {
+    vterm_screen_free(vt->screen);
+  }
+
+  if (vt->state) {
+    vterm_state_free(vt->state);
+  }
+
+  vterm_allocator_free(vt, vt->outbuffer);
+  vterm_allocator_free(vt, vt->tmpbuffer);
+
+  vterm_allocator_free(vt, vt);
+}
+
+void *vterm_allocator_malloc(VTerm *vt, size_t size)
+{
+  return (*vt->allocator->malloc)(size, vt->allocdata);
+}
+
+void vterm_allocator_free(VTerm *vt, void *ptr)
+{
+  (*vt->allocator->free)(ptr, vt->allocdata);
+}
+
+void vterm_get_size(const VTerm *vt, int *rowsp, int *colsp)
+{
+  if (rowsp) {
+    *rowsp = vt->rows;
+  }
+  if (colsp) {
+    *colsp = vt->cols;
+  }
+}
+
+void vterm_set_size(VTerm *vt, int rows, int cols)
+{
+  if (rows < 1 || cols < 1) {
+    return;
+  }
+
+  vt->rows = rows;
+  vt->cols = cols;
+
+  if (vt->parser.callbacks && vt->parser.callbacks->resize) {
+    (*vt->parser.callbacks->resize)(rows, cols, vt->parser.cbdata);
+  }
+}
+
+void vterm_set_utf8(VTerm *vt, int is_utf8)
+{
+  vt->mode.utf8 = (unsigned)is_utf8;
+}
+
+void vterm_output_set_callback(VTerm *vt, VTermOutputCallback *func, void *user)
+{
+  vt->outfunc = func;
+  vt->outdata = user;
+}
+
+void vterm_push_output_bytes(VTerm *vt, const char *bytes, size_t len)
+{
+  if (vt->outfunc) {
+    (vt->outfunc)(bytes, len, vt->outdata);
+    return;
+  }
+
+  if (len > vt->outbuffer_len - vt->outbuffer_cur) {
+    return;
+  }
+
+  memcpy(vt->outbuffer + vt->outbuffer_cur, bytes, len);
+  vt->outbuffer_cur += len;
+}
+
+void vterm_push_output_sprintf(VTerm *vt, const char *format, ...)
+  FUNC_ATTR_PRINTF(2, 3)
+{
+  va_list args;
+  va_start(args, format);
+  size_t len = (size_t)vsnprintf(vt->tmpbuffer, vt->tmpbuffer_len, format, args);
+  vterm_push_output_bytes(vt, vt->tmpbuffer, len);
+  va_end(args);
+}
+
+void vterm_push_output_sprintf_ctrl(VTerm *vt, uint8_t ctrl, const char *fmt, ...)
+  FUNC_ATTR_PRINTF(3, 4)
+{
+  size_t cur;
+
+  if (ctrl >= 0x80 && !vt->mode.ctrl8bit) {
+    cur = (size_t)snprintf(vt->tmpbuffer, vt->tmpbuffer_len, ESC_S "%c", ctrl - 0x40);
+  } else {
+    cur = (size_t)snprintf(vt->tmpbuffer, vt->tmpbuffer_len, "%c", ctrl);
+  }
+
+  if (cur >= vt->tmpbuffer_len) {
+    return;
+  }
+
+  va_list args;
+  va_start(args, fmt);
+  cur += (size_t)vsnprintf(vt->tmpbuffer + cur, vt->tmpbuffer_len - cur, fmt, args);
+  va_end(args);
+
+  if (cur >= vt->tmpbuffer_len) {
+    return;
+  }
+
+  vterm_push_output_bytes(vt, vt->tmpbuffer, cur);
+}
+
+void vterm_push_output_sprintf_str(VTerm *vt, uint8_t ctrl, bool term, const char *fmt, ...)
+  FUNC_ATTR_PRINTF(4, 5)
+{
+  size_t cur = 0;
+
+  if (ctrl) {
+    if (ctrl >= 0x80 && !vt->mode.ctrl8bit) {
+      cur = (size_t)snprintf(vt->tmpbuffer, vt->tmpbuffer_len, ESC_S "%c", ctrl - 0x40);
+    } else {
+      cur = (size_t)snprintf(vt->tmpbuffer, vt->tmpbuffer_len, "%c", ctrl);
+    }
+
+    if (cur >= vt->tmpbuffer_len) {
+      return;
+    }
+  }
+
+  va_list args;
+  va_start(args, fmt);
+  cur += (size_t)vsnprintf(vt->tmpbuffer + cur, vt->tmpbuffer_len - cur, fmt, args);
+  va_end(args);
+
+  if (cur >= vt->tmpbuffer_len) {
+    return;
+  }
+
+  if (term) {
+    cur += (size_t)snprintf(vt->tmpbuffer + cur, vt->tmpbuffer_len - cur,
+                            vt->mode.ctrl8bit ? "\x9C" : ESC_S "\\");  // ST
+
+    if (cur >= vt->tmpbuffer_len) {
+      return;
+    }
+  }
+
+  vterm_push_output_bytes(vt, vt->tmpbuffer, cur);
+}
+
+VTermValueType vterm_get_attr_type(VTermAttr attr)
+{
+  switch (attr) {
+  case VTERM_ATTR_BOLD:
+    return VTERM_VALUETYPE_BOOL;
+  case VTERM_ATTR_UNDERLINE:
+    return VTERM_VALUETYPE_INT;
+  case VTERM_ATTR_ITALIC:
+    return VTERM_VALUETYPE_BOOL;
+  case VTERM_ATTR_BLINK:
+    return VTERM_VALUETYPE_BOOL;
+  case VTERM_ATTR_REVERSE:
+    return VTERM_VALUETYPE_BOOL;
+  case VTERM_ATTR_CONCEAL:
+    return VTERM_VALUETYPE_BOOL;
+  case VTERM_ATTR_STRIKE:
+    return VTERM_VALUETYPE_BOOL;
+  case VTERM_ATTR_FONT:
+    return VTERM_VALUETYPE_INT;
+  case VTERM_ATTR_FOREGROUND:
+    return VTERM_VALUETYPE_COLOR;
+  case VTERM_ATTR_BACKGROUND:
+    return VTERM_VALUETYPE_COLOR;
+  case VTERM_ATTR_SMALL:
+    return VTERM_VALUETYPE_BOOL;
+  case VTERM_ATTR_BASELINE:
+    return VTERM_VALUETYPE_INT;
+  case VTERM_ATTR_URI:
+    return VTERM_VALUETYPE_INT;
+
+  case VTERM_N_ATTRS:
+    return 0;
+  }
+  return 0;  // UNREACHABLE
+}
+
+void vterm_scroll_rect(VTermRect rect, int downward, int rightward,
+                       int (*moverect)(VTermRect src, VTermRect dest, void *user),
+                       int (*eraserect)(VTermRect rect, int selective, void *user), void *user)
+{
+  VTermRect src;
+  VTermRect dest;
+
+  if (abs(downward) >= rect.end_row - rect.start_row
+      || abs(rightward) >= rect.end_col - rect.start_col) {
+    // Scroll more than area; just erase the lot
+    (*eraserect)(rect, 0, user);
+    return;
+  }
+
+  if (rightward >= 0) {
+    // rect: [XXX................]
+    // src:     [----------------]
+    // dest: [----------------]
+    dest.start_col = rect.start_col;
+    dest.end_col = rect.end_col - rightward;
+    src.start_col = rect.start_col + rightward;
+    src.end_col = rect.end_col;
+  } else {
+    // rect: [................XXX]
+    // src:  [----------------]
+    // dest:    [----------------]
+    int leftward = -rightward;
+    dest.start_col = rect.start_col + leftward;
+    dest.end_col = rect.end_col;
+    src.start_col = rect.start_col;
+    src.end_col = rect.end_col - leftward;
+  }
+
+  if (downward >= 0) {
+    dest.start_row = rect.start_row;
+    dest.end_row = rect.end_row - downward;
+    src.start_row = rect.start_row + downward;
+    src.end_row = rect.end_row;
+  } else {
+    int upward = -downward;
+    dest.start_row = rect.start_row + upward;
+    dest.end_row = rect.end_row;
+    src.start_row = rect.start_row;
+    src.end_row = rect.end_row - upward;
+  }
+
+  if (moverect) {
+    (*moverect)(dest, src, user);
+  }
+
+  if (downward > 0) {
+    rect.start_row = rect.end_row - downward;
+  } else if (downward < 0) {
+    rect.end_row = rect.start_row - downward;
+  }
+
+  if (rightward > 0) {
+    rect.start_col = rect.end_col - rightward;
+  } else if (rightward < 0) {
+    rect.end_col = rect.start_col - rightward;
+  }
+
+  (*eraserect)(rect, 0, user);
+}