Fix web pixel buffer access

1 files changed, 136 insertions, 75 deletions

diff --git a/reduced_system_layer.c b/reduced_system_layer.c
index ae28109..5e5bfdf 100755
--- a/reduced_system_layer.c
+++ b/reduced_system_layer.c
@@ -287,8 +287,12 @@ i32 main(i32 argc, c8 **argv);
 
 //  The pixel size will increase when the frame duration is higher.
 #ifndef MAX_FRAME_DURATION
+#if defined(__wasm__)
+#define MAX_FRAME_DURATION 33
+#else
 #define MAX_FRAME_DURATION 83
 #endif
+#endif
 
 //  The pixel size value will reset if the frame duration is higher.
 #ifndef FRAME_DURATION_HARD_LIMIT
@@ -761,7 +765,17 @@ static i64 max2_i64_(i64 x, i64 y) {
 
 //  TEMP
 #if defined(__wasm__)
-#define LOG_ERROR(...) do { } while (0)
+void log_error_impl(i32 file_len, c8 const *file, i32 line, i32 func_len, c8 const *func, i32 text_len, c8 const *text);
+#define LOG_ERROR(text_, ...)           \
+  do {                                  \
+    i32 len = 0;                        \
+    while ((text_)[len] != '\0') ++len; \
+    log_error_impl(                     \
+      sizeof(__FILE__) - 1, __FILE__,   \
+      __LINE__,                         \
+      sizeof(__func__) - 1, __func__,   \
+      len, text_);                      \
+  } while (0)
 #else
 #include <stdio.h>
 #define LOG_ERROR(...)                                            \
@@ -848,52 +862,68 @@ void *memory_buffer_allocate(i64 size, i64 alignment, i64 previous_size, void *p
   i64 num_chunks = (align_(size, alignment)       + MEMORY_CHUNK_SIZE - 1) / MEMORY_CHUNK_SIZE;
   i64 chunk      = (g_platform.memory_buffer_size + MEMORY_CHUNK_SIZE - 1) / MEMORY_CHUNK_SIZE;
 
-  //  Search free space
-  for (i64 i = 0;; ++i) {
-    while ((i % 64) == 0
-        &&  i < occupied_len_bits
-        && (i + 64 <= prev_chunk || i >= prev_chunk + prev_num_chunks)
-        && occupied[i / 64] == ~0ull)
-      i += 64;
-    while ((i % 8) == 0
-        &&  i < occupied_len_bits
-        && (i + 8 <= prev_chunk || i >= prev_chunk + prev_num_chunks)
-        && ((u8 *) occupied)[i / 8] == 255u)
-      i += 8;
-    if (i >= occupied_len_bits) break;
-    b8 is_occupied = 0;
-    for (i64 j = i; j < i + num_chunks; ++j) {
-      if (j >= prev_chunk && j < prev_chunk + prev_num_chunks) continue;
-      if ((occupied[j / 64] & (1ull << (j % 64))) == 0)        continue;
-      is_occupied = 1;
-      break;
+  if (num_chunks == prev_num_chunks)
+    return previous_data;
+
+  u8 *dst = NULL;
+
+  if (num_chunks < prev_num_chunks) {
+    //  Reuse previously allocated space.
+    chunk = prev_chunk;
+    dst   = data + chunk * MEMORY_CHUNK_SIZE;
+  } else {
+    //  Search free space
+    for (i64 i = 0;; ++i) {
+      while ((i % 64) == 0
+          &&  i < occupied_len_bits
+          && (i + 64 <= prev_chunk || i >= prev_chunk + prev_num_chunks)
+          && occupied[i / 64] == ~0ull)
+        i += 64;
+      while ((i % 8) == 0
+          &&  i < occupied_len_bits
+          && (i + 8 <= prev_chunk || i >= prev_chunk + prev_num_chunks)
+          && ((u8 *) occupied)[i / 8] == 255u)
+        i += 8;
+      if (i >= occupied_len_bits) break;
+      b8 is_occupied = 0;
+      for (i64 j = i; j < i + num_chunks; ++j) {
+        if (j >= prev_chunk && j < prev_chunk + prev_num_chunks) continue;
+        if ((occupied[j / 64] & (1ull << (j % 64))) == 0)        continue;
+        is_occupied = 1;
+        break;
+      }
+      if (!is_occupied) {
+        chunk = i;
+        break;
+      }
     }
-    if (!is_occupied) {
-      chunk = i;
-      break;
+
+    //  Check if out of memory
+    dst = data + chunk * MEMORY_CHUNK_SIZE;
+    if (dst + size > g_platform.memory_buffer + g_platform.memory_buffer_size) {
+      LOG_ERROR("Out of memory: %lld bytes", size - previous_size);
+      return NULL;
     }
-  }
 
-  //  Check if out of memory
-  u8 *dst = data + chunk * MEMORY_CHUNK_SIZE;
-  if (dst + size > g_platform.memory_buffer + g_platform.memory_buffer_size) {
-    LOG_ERROR("Out of memory: %lld bytes", size - previous_size);
-    return NULL;
+    //  Claim required space
+    for (i64 j = chunk; j < chunk + num_chunks; ++j)
+      occupied[j / 64] |= 1ull << (j % 64);
   }
 
-  //  Claim required space
-  for (i64 j = chunk; j < chunk + num_chunks; ++j)
-    occupied[j / 64] |= 1ull << (j % 64);
-
-  //  Copy data
-  u8 *src = data + prev_chunk * MEMORY_CHUNK_SIZE;
-  i64 len = size < previous_size ? size : previous_size;
-  if (dst > src)
-    for (i64 k = len - 1; k >= 0; --k)
-      dst[k] = src[k];
-  else
-    for (i64 k = 0; k < len; ++k)
-      dst[k] = src[k];
+  if (chunk != prev_chunk) {
+    //  Copy data
+    i64 len = size < previous_size ? size : previous_size;
+    u8 *s0  = data + prev_chunk * MEMORY_CHUNK_SIZE;
+    u8 *s1  = s0 + len - 1;
+    u8 *d0  = dst;
+    u8 *d1  = dst + len - 1;
+    if (d0 > s0)
+      for (u8 *d = d1, *s = s1; d >= d0; --d, --s)
+        *d = *s;
+    else
+      for (u8 *d = d0, *s = s0; d <= d1; ++d, ++s)
+        *d = *s;
+  }
 
   //  Free previous space
   for (i64 j = prev_chunk; j < prev_chunk + prev_num_chunks; ++j) {
@@ -2079,7 +2109,7 @@ void handle_primary_sound(void) {
 
   if (num_frames > MAX_NUM_PRIMARY_SOUND_FRAMES) {
     LOG_ERROR("Sound buffer overflow.");
-    num_frames = MAX_NUM_PRIMARY_SOUND_FRAMES;
+    num_frames %= MAX_NUM_PRIMARY_SOUND_FRAMES;
   }
 
   i32 s;
@@ -2559,7 +2589,7 @@ b8 wayland_screenshot_(i64 max_num_pixels, i64 *width, i64 *height, vec4_f32 *pi
 
   if (state.display == NULL) {
     LOG_ERROR("wl_display_connect failed.");
-    goto finalize;
+    goto _finalize;
   }
 
   state.registry = wl_display_get_registry(state.display);
@@ -2572,17 +2602,17 @@ b8 wayland_screenshot_(i64 max_num_pixels, i64 *width, i64 *height, vec4_f32 *pi
 
   if (state.shm == NULL) {
     LOG_ERROR("Compositor does not support wl_shm.");
-    goto finalize;
+    goto _finalize;
   }
 
   if (wl_list_empty(&state.outputs)) {
     LOG_ERROR("No wl_output.");
-    goto finalize;
+    goto _finalize;
   }
 
   if (state.screencopy_manager == NULL) {
     LOG_ERROR("Compositor does not support wlr-screencopy-unstable-v1.");
-    goto finalize;
+    goto _finalize;
   }
 
   u64 n_pending = 0;
@@ -2605,71 +2635,82 @@ b8 wayland_screenshot_(i64 max_num_pixels, i64 *width, i64 *height, vec4_f32 *pi
 
   if (n_pending == 0) {
     LOG_ERROR("Supplied geometry did not intersect with any outputs.");
-    goto finalize;
+    goto _finalize;
   }
 
   b8 done = 0;
 
   while (!done && wl_display_dispatch(state.display) != -1) {
     if (!state.ok)
-      goto finalize;
+      goto _finalize;
     usleep(0);
     done = (state.n_done == n_pending);
   }
 
   if (!done) {
     LOG_ERROR("Failed to screenshoot all outputs.");
-    goto finalize;
+    goto _finalize;
   }
 
   *width  = 0;
   *height = 0;
 
+  //  NOTE: We grab only one output.
+
+  //  TODO: Allow to choose the desired output.
+
   wl_list_for_each(output, &state.outputs, link) {
     WL_Buffer_ *buffer = output->buffer;
     if (buffer == NULL)                 continue;
     if (!check_format_(buffer->format)) continue;
 
-    if (*width < buffer->width)
-      *width = buffer->width;
-    *height += buffer->height;
+    *width  = buffer->width;
+    *height = buffer->height;
+    break;
   }
 
   if (pixels == NULL || *width * *height > max_num_pixels) {
     ok = 1;
-    goto finalize;
+    goto _finalize;
   }
 
   for (i32 i = 0; i < *width * *height; ++i)
     pixels[i] = (vec4_f32) { 0.f, 0.f, 0.f, 1.f };
 
-  i32 y0 = 0;
-
   wl_list_for_each(output, &state.outputs, link) {
     WL_Buffer_ *buffer = output->buffer;
     if (buffer == NULL)                 continue;
     if (!check_format_(buffer->format)) continue;
 
-    for (i32 j = 0; j < buffer->height; ++j)
-      for (i32 i = 0; i < buffer->width; ++i) {
-        vec3_f32 c = rgb_f32_from_u32_(((u32 *) buffer->data)[j * (buffer->stride / 4) + i]);
+    if (*width != buffer->width) {
+      LOG_ERROR("Sanity");
+      break;
+    }
+
+    for (i32 j = 0; j < buffer->height; ++j) {
+      vec4_f32 *d     = pixels + j * *width;
+      vec4_f32 *d_end = d + *width;
+      u32      *s     = ((u32 *) buffer->data) + j * (buffer->stride / 4);
 
-        pixels[(y0 + j) * *width + i] = (vec4_f32) {
+      for (; d < d_end; ++d, ++s) {
+        vec3_f32 c = rgb_f32_from_u32_(*s);
+        *d = (vec4_f32) {
           .x = c.x,
           .y = c.y,
           .z = c.z,
           .w = 1.f,
         };
       }
+    }
 
-    y0 += buffer->height;
+    break;
   }
 
   ok = 1;
 
   WL_Output_ *output_tmp;
 
-finalize:
+_finalize:
   wl_list_for_each_safe(output, output_tmp, &state.outputs, link) {
     wl_list_remove(&output->link);
     free(output->name);
@@ -3579,6 +3620,20 @@ void write_clipboard_text(i64 size, c8 *data) {
     XSetSelectionOwner(_display, _clipboard, _window, CurrentTime);
 }
 
+b8 x11_get_root_(void) {
+  Window root, parent, *children;
+  u32 num_children;
+
+  if(!XQueryTree(_display, _window, &root, &parent, &children, &num_children))
+    return 0;
+
+  if (children != NULL)
+    XFree((c8 *) children);
+
+  _root_window = root;
+  return 1;
+}
+
 b8 x11_screenshot_(i64 max_num_pixels, i64 *width, i64 *height, vec4_f32 *pixels) {
   if (_display == NULL) {
     LOG_ERROR("No display.");
@@ -3589,6 +3644,8 @@ b8 x11_screenshot_(i64 max_num_pixels, i64 *width, i64 *height, vec4_f32 *pixels
   i32 display_width  = DisplayWidth (_display, screen);
   i32 display_height = DisplayHeight(_display, screen);
 
+  x11_get_root_();
+
   XImage *image = XGetImage(_display, _root_window, 0, 0, display_width, display_height, AllPlanes, ZPixmap);
 
   if (image == NULL) {
@@ -3600,17 +3657,22 @@ b8 x11_screenshot_(i64 max_num_pixels, i64 *width, i64 *height, vec4_f32 *pixels
   *height = image->height;
 
   if (pixels != NULL && image->width * image->height <= max_num_pixels)
-    for (i64 j = 0; j < image->height; ++j)
-      for (i64 i = 0; i < image->width; ++i) {
-        vec3_f32 f = rgb_f32_from_u32_(XGetPixel(image, i, j));
-
-        pixels[j * image->width + i] = (vec4_f32) {
-          .x = f.x,
-          .y = f.y,
-          .z = f.z,
+    for (i64 j = 0; j < image->height; ++j) {
+      vec4_f32 *d       = pixels + j * image->width;
+      vec4_f32 *d_first = d;
+      vec4_f32 *d_end   = d + image->width;
+
+      for (; d < d_end; ++d) {
+        vec3_f32 c = rgb_f32_from_u32_(XGetPixel(image, d - d_first, j));
+
+        *d = (vec4_f32) {
+          .x = c.x,
+          .y = c.y,
+          .z = c.z,
           .w = 1.f,
         };
       }
+    }
 
   XDestroyImage(image);
   return 1;
@@ -3980,11 +4042,7 @@ __attribute__((export_name("js_title"))) void *js_title(void) {
   return g_platform.title;
 }
 
-__attribute__((export_name("js_pixels"))) void *js_pixels(void) {
-  return _internal_pixels;
-}
-
-__attribute__((export_name("js_frame"))) void js_frame(i32 frame_width, i32 frame_height, i32 num_samples) {
+__attribute__((export_name("js_frame"))) void *js_frame(i32 frame_width, i32 frame_height, i32 num_samples) {
   i64 frame_time = current_utc_time_in_milliseconds();
 
   _num_events += pixel_size_update_(frame_width, frame_height);
@@ -4010,6 +4068,8 @@ __attribute__((export_name("js_frame"))) void js_frame(i32 frame_width, i32 fram
 
   if (do_render)
     pixel_size_calibrate_(current_utc_time_in_milliseconds() - frame_time);
+
+  return _internal_pixels;
 }
 
 __attribute__((export_name("js_mousemove"))) void js_mousemove(i32 x, i32 y) {
@@ -4111,6 +4171,7 @@ __attribute__((export_name("js_drop"))) i32 js_drop(i32 name_len, i32 data_size)
     drop_files_set_name_(n, 0, NULL);
     drop_files_set_data_(n, 0);
     drop_files_set_num_(n);
+    LOG_ERROR("File too big.");
     return 0;
   }