Cleanup

Makefile

@@ -44,7 +44,7 @@ UNICODE_OBJ := $(patsubst libs/unicode_width/%.c,$(OBJ_DIR)/unicode_width/%.o,$(
 
 LIBS := $(PCRE_LIBS) $(LIBGRAPHEME_LIBS) $(MRUBY_LIBS)
 
-SRC := $(wildcard $(SRC_DIR)/**/*.cc) $(wildcard $(SRC_DIR)/*.cc)
+SRC := $(shell find $(SRC_DIR) -type f -name '*.cc')
 OBJ_DEBUG := $(patsubst $(SRC_DIR)/%.cc,$(OBJ_DIR)/debug/%.o,$(SRC))
 OBJ_RELEASE := $(patsubst $(SRC_DIR)/%.cc,$(OBJ_DIR)/release/%.o,$(SRC))
 

flake.nix

@@ -58,6 +58,7 @@
           gnumake
           xxd
           bash
+          findutils
         ];
 
         buildInputs = with pkgs; [
@@ -100,6 +101,7 @@
           hostPkgs.xxd
           hostPkgs.gdb
           hostPkgs.binutils
+          hostPkgs.findutils
 
           pkgs.libgrapheme
           pkgs.pcre2

include/io/file.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include "pch.h"
+
+inline int read_file(const char *path, char **text, uint32_t *len) {
+  FILE *f = fopen(path, "rb");
+  if (!f)
+    return 0;
+
+  fseek(f, 0, SEEK_END);
+  long size = ftell(f);
+  fseek(f, 0, SEEK_SET);
+
+  if (size < 0 || size > UINT32_MAX) {
+    fclose(f);
+    return 0;
+  }
+
+  *len = (uint32_t)size;
+
+  *text = (char *)malloc(*len + 1);
+  if (!*text) {
+    fclose(f);
+    return 0;
+  }
+
+  size_t read = fread(*text, 1, *len, f);
+  fclose(f);
+
+  if (read != *len) {
+    free(*text);
+    *text = NULL;
+    *len = 0;
+    return 0;
+  }
+
+  (*text)[*len] = '\0'; // handy if treating it as a C string
+
+  return 1;
+}

include/pch.h

@@ -30,6 +30,7 @@ extern "C" {
 #include <fstream>
 #include <functional>
 #include <immintrin.h>
+#include <iostream>
 #include <limits.h>
 #include <map>
 #include <mutex>

include/vase/buffer/append.h

@@ -1,9 +1,12 @@
 #pragma once
 
+#include "buffer.h"
 #include "pch.h"
+#include <cstdint>
 
-struct AppendBuffer {
+struct AppendBuffer : Buffer {
   static constexpr uint32_t CHUNK_SIZE = 1 << 16;
+
   using TChunk = char[CHUNK_SIZE];
   std::vector<TChunk *> buf;
   TChunk *t_current;
@@ -22,9 +25,14 @@ struct AppendBuffer {
   inline void key(char c);
   void append(const char *text, uint32_t length);
 
+  const char *read(uint32_t pos, uint32_t *out_len);
+  uint32_t count_lines(uint32_t pos, uint32_t length);
+
 private:
   inline void new_text_chunk();
   inline void new_line_chunk();
 
+  inline uint32_t find_newline(uint32_t target, uint32_t low, uint32_t high);
+
   inline void _append(const char *text, uint32_t length);
 };

include/vase/buffer/buffer.h

@@ -0,0 +1,10 @@
+#pragma once
+
+#include "pch.h"
+
+struct Buffer {
+  virtual const char *read(uint32_t pos, uint32_t *out_len) = 0;
+  virtual uint32_t count_lines(uint32_t pos, uint32_t length) = 0;
+
+  virtual ~Buffer() = default;
+};

include/vase/buffer/original.h

@@ -1,8 +1,9 @@
 #pragma once
 
+#include "buffer.h"
 #include "pch.h"
 
-struct OriginalBuffer {
+struct OriginalBuffer : Buffer {
   char *buf;
   uint32_t length;
   std::vector<uint32_t> newlines;
@@ -23,4 +24,7 @@ struct OriginalBuffer {
   ~OriginalBuffer() {
     free(buf);
   }
+
+  const char *read(uint32_t pos, uint32_t *out_len);
+  uint32_t count_lines(uint32_t pos, uint32_t length);
 };

include/vase/shard.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include "buffer/buffer.h"
 #include "pch.h"
 
 struct Shard {
@@ -14,7 +15,7 @@ struct Shard {
   std::atomic_uint32_t refs;
 
   Shard(ShardKind kind, uint32_t length, uint32_t lines)
-      : kind(kind), length(length), lines(lines) {};
+      : kind(kind), length(length), lines(lines), refs(0) {};
 };
 
 struct ShardPtr {
@@ -53,17 +54,18 @@ struct Branch : Shard {
 
   Branch(Shard *l, Shard *r)
       : Shard(ShardKind::Branch, l->length + r->length, l->lines + r->lines),
-        left(ShardPtr(l)), right(ShardPtr(r)) {};
+        left(l), right(r) {};
 };
 
 struct Petal : Shard {
-  enum struct Kind {
+  Buffer *source;
-    Original,
-    Append
-  } source;
 
   uint32_t pos;
 
-  Petal(uint32_t length, uint32_t lines, Kind source, uint32_t pos)
+  Petal(uint32_t length, uint32_t lines, Buffer *source, uint32_t pos)
       : Shard(ShardKind::Petal, length, lines), source(source), pos(pos) {};
 };
+
+std::pair<ShardPtr, ShardPtr> split(Shard *n, uint32_t offset);
+
+void print_shard(const Shard *shard, int depth = 0);

include/vase/vase.h

@@ -1,7 +1,7 @@
 #pragma once
 
-#include "append_buffer.h"
+#include "buffer/append.h"
-#include "original_buffer.h"
+#include "buffer/original.h"
 #include "pch.h"
 #include "shard.h"
 
@@ -21,7 +21,7 @@ struct Vase {
     root = new Petal(
       length,
       original.newlines.size(),
-      Petal::Kind::Original,
+      &original,
       0
     );
   }

src/main.cc

@@ -1,5 +1,19 @@
+#include "io/file.h"
 #include "pch.h"
+#include "vase/shard.h"
+#include "vase/vase.h"
 
 int main() {
+  char *text;
+  uint32_t len;
+
+  int s = read_file("./flake.nix", &text, &len);
+  if (!s)
+    return 1;
+
+  Vase vase = Vase(text, len);
+
+  print_shard(vase.root.ptr);
+
   return 0;
 }

src/vase/append_buffer.cc

@@ -1,71 +0,0 @@
-#include "vase/append_buffer.h"
-
-AppendBuffer::AppendBuffer() {
-  new_text_chunk();
-  new_line_chunk();
-}
-
-AppendBuffer::~AppendBuffer() {
-  for (auto p : buf)
-    free(p);
-  for (auto p : newlines)
-    free(p);
-}
-
-inline void AppendBuffer::key(char c) {
-  if (t_offset == CHUNK_SIZE)
-    new_text_chunk();
-  (*t_current)[t_offset++] = c;
-  if (c == '\n') {
-    if (l_offset == CHUNK_SIZE)
-      new_line_chunk();
-    (*l_current)[l_offset++] = current_offset;
-  }
-  ++current_offset;
-}
-
-void AppendBuffer::append(const char *text, uint32_t length) {
-  while (length) {
-    uint32_t space = CHUNK_SIZE - t_offset;
-    if (space == 0) {
-      new_text_chunk();
-      space = CHUNK_SIZE;
-    }
-    uint32_t copy = length < space ? length : space;
-    _append(text, copy);
-    text += copy;
-    length -= copy;
-  }
-}
-
-inline void AppendBuffer::new_text_chunk() {
-  t_current = (TChunk *)malloc(sizeof(TChunk));
-  buf.push_back(t_current);
-  t_offset = 0;
-}
-
-inline void AppendBuffer::new_line_chunk() {
-  l_current = (LChunk *)malloc(sizeof(LChunk));
-  newlines.push_back(l_current);
-  l_offset = 0;
-}
-
-inline void AppendBuffer::_append(const char *text, uint32_t length) {
-  memcpy((*t_current) + t_offset, text, length);
-
-  const char *p = text;
-  const char *end = text + length;
-
-  while (p < end) {
-    p = (const char *)memchr(p, '\n', end - p);
-    if (!p)
-      break;
-    if (l_offset == CHUNK_SIZE)
-      new_line_chunk();
-    (*l_current)[l_offset++] = current_offset + uint32_t(p - text);
-    p++;
-  }
-
-  t_offset += length;
-  current_offset += length;
-}

src/vase/buffer/append.cc

@@ -0,0 +1,148 @@
+#include "vase/buffer/append.h"
+#include <cstdint>
+
+AppendBuffer::AppendBuffer() {
+  new_text_chunk();
+  new_line_chunk();
+}
+
+AppendBuffer::~AppendBuffer() {
+  for (auto p : buf)
+    free(p);
+  for (auto p : newlines)
+    free(p);
+}
+
+inline void AppendBuffer::key(char c) {
+  if (t_offset == CHUNK_SIZE)
+    new_text_chunk();
+  (*t_current)[t_offset++] = c;
+  if (c == '\n') {
+    if (l_offset == CHUNK_SIZE)
+      new_line_chunk();
+    (*l_current)[l_offset++] = current_offset;
+  }
+  ++current_offset;
+}
+
+void AppendBuffer::append(const char *text, uint32_t length) {
+  while (length) {
+    uint32_t space = CHUNK_SIZE - t_offset;
+    if (space == 0) {
+      new_text_chunk();
+      space = CHUNK_SIZE;
+    }
+    uint32_t copy = length < space ? length : space;
+    _append(text, copy);
+    text += copy;
+    length -= copy;
+  }
+}
+
+const char *AppendBuffer::read(uint32_t pos, uint32_t *out_len) {
+  if (pos >= current_offset)
+    return nullptr;
+  uint32_t local_offset = pos % CHUNK_SIZE;
+  if (out_len) {
+    uint32_t remaining = current_offset - pos;
+    uint32_t until_chunk_end = CHUNK_SIZE - local_offset;
+    *out_len = std::min(remaining, until_chunk_end);
+  }
+  return &(*buf[pos / CHUNK_SIZE])[local_offset];
+}
+
+uint32_t AppendBuffer::find_newline(uint32_t target, uint32_t low, uint32_t high) {
+  if (low >= high)
+    return low;
+
+  uint32_t first_chunk = low / CHUNK_SIZE;
+  uint32_t last_chunk = (high - 1) / CHUNK_SIZE;
+
+  uint32_t left = first_chunk;
+  uint32_t right = last_chunk;
+
+  while (left < right) {
+    uint32_t mid = left + (right - left) / 2;
+
+    uint32_t first_value = (*newlines[mid])[0];
+
+    if (first_value < target)
+      left = mid + 1;
+    else
+      right = mid;
+  }
+
+  uint32_t chunk = left;
+
+  if (chunk > first_chunk) {
+    LChunk &prev = *newlines[chunk - 1];
+
+    uint32_t prev_size =
+      (chunk - 1 == newlines.size() - 1) ? l_offset : CHUNK_SIZE;
+
+    if (prev[prev_size - 1] >= target)
+      chunk--;
+  }
+
+  LChunk &c = *newlines[chunk];
+
+  uint32_t chunk_size =
+    (chunk == newlines.size() - 1) ? l_offset : CHUNK_SIZE;
+
+  uint32_t l = 0;
+  uint32_t r = chunk_size;
+
+  while (l < r) {
+    uint32_t m = l + (r - l) / 2;
+
+    if (c[m] < target)
+      l = m + 1;
+    else
+      r = m;
+  }
+
+  return chunk * CHUNK_SIZE + l;
+}
+
+uint32_t AppendBuffer::count_lines(uint32_t pos, uint32_t length) {
+  if (newlines.empty())
+    return 0;
+
+  uint32_t total_newlines = CHUNK_SIZE * (newlines.size() - 1) + l_offset;
+  uint32_t pos_index = find_newline(pos, 0, total_newlines);
+  uint32_t end_index = find_newline(pos + length, pos_index, total_newlines);
+
+  return end_index - pos_index;
+}
+
+inline void AppendBuffer::new_text_chunk() {
+  t_current = (TChunk *)malloc(sizeof(TChunk));
+  buf.push_back(t_current);
+  t_offset = 0;
+}
+
+inline void AppendBuffer::new_line_chunk() {
+  l_current = (LChunk *)malloc(sizeof(LChunk));
+  newlines.push_back(l_current);
+  l_offset = 0;
+}
+
+inline void AppendBuffer::_append(const char *text, uint32_t length) {
+  memcpy((*t_current) + t_offset, text, length);
+
+  const char *p = text;
+  const char *end = text + length;
+
+  while (p < end) {
+    p = (const char *)memchr(p, '\n', end - p);
+    if (!p)
+      break;
+    if (l_offset == CHUNK_SIZE)
+      new_line_chunk();
+    (*l_current)[l_offset++] = current_offset + uint32_t(p - text);
+    p++;
+  }
+
+  t_offset += length;
+  current_offset += length;
+}

src/vase/buffer/original.cc

@@ -0,0 +1,24 @@
+#include "vase/buffer/original.h"
+
+const char *OriginalBuffer::read(uint32_t pos, uint32_t *out_len) {
+  if (pos >= length)
+    return nullptr;
+  *out_len = length - pos;
+  return buf + pos;
+}
+
+uint32_t OriginalBuffer::count_lines(uint32_t pos, uint32_t length) {
+  auto start = std::lower_bound(
+    newlines.begin(),
+    newlines.end(),
+    pos
+  );
+
+  auto end = std::lower_bound(
+    start,
+    newlines.end(),
+    pos + length
+  );
+
+  return (uint32_t)(end - start);
+}

src/vase/shard.cc

@@ -0,0 +1,103 @@
+#include "vase/shard.h"
+
+std::pair<ShardPtr, ShardPtr> split(Shard *n, uint32_t offset) {
+  if (!n)
+    return {nullptr, nullptr};
+
+  if (offset == 0)
+    return {nullptr, ShardPtr(n)};
+
+  if (offset == n->length)
+    return {ShardPtr(n), nullptr};
+
+  if (n->kind == Shard::ShardKind::Branch) {
+    Branch *b = static_cast<Branch *>(n);
+
+    if (offset < b->left.ptr->length) {
+      auto [a, b2] = split(b->left.ptr, offset);
+
+      return {
+        a,
+        ShardPtr(new Branch(
+          b2.ptr,
+          b->right.ptr
+        ))
+      };
+    } else {
+      auto [a, b2] = split(
+        b->right.ptr,
+        offset - b->left.ptr->length
+      );
+
+      return {
+        ShardPtr(new Branch(
+          b->left.ptr,
+          a.ptr
+        )),
+        b2
+      };
+    }
+  }
+
+  Petal *p = static_cast<Petal *>(n);
+
+  auto left = new Petal(
+    offset,
+    p->source->count_lines(0, offset),
+    p->source,
+    p->pos
+  );
+
+  auto right = new Petal(
+    p->length - offset,
+    p->source->count_lines(offset, p->length),
+    p->source,
+    p->pos + offset
+  );
+
+  return {
+    ShardPtr(left),
+    ShardPtr(right)
+  };
+}
+
+void print_shard(const Shard *shard, int depth) {
+  if (!shard) {
+    std::cout << std::string(depth * 2, ' ') << "<null>\n";
+    return;
+  }
+
+  std::string indent(depth * 2, ' ');
+
+  std::cout << indent;
+
+  if (shard->kind == Shard::ShardKind::Branch) {
+    auto *branch = static_cast<const Branch *>(shard);
+
+    std::cout
+      << "Branch"
+      << " @" << shard
+      << " len=" << shard->length
+      << " lines=" << shard->lines
+      << " refs=" << shard->refs.load()
+      << "\n";
+
+    std::cout << indent << "├─ left:\n";
+    print_shard(branch->left.ptr, depth + 2);
+
+    std::cout << indent << "└─ right:\n";
+    print_shard(branch->right.ptr, depth + 2);
+  } else {
+    auto *petal = static_cast<const Petal *>(shard);
+
+    std::cout
+      << "Petal"
+      << " @" << shard
+      << " len=" << shard->length
+      << " lines=" << shard->lines
+      << " refs=" << shard->refs.load()
+      << " source=@" << petal->source
+      << " pos=" << petal->pos
+      << "\n";
+  }
+}