1 files changed, 888 insertions, 0 deletions
diff --git a/cmark/src/node.c b/cmark/src/node.c
new file mode 100644
index 0000000000..c1492545e4
--- /dev/null
+++ b/cmark/src/node.c
@@ -0,0 +1,888 @@
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "node.h"
+
+static void S_node_unlink(cmark_node *node);
+
+bool cmark_node_is_block(cmark_node *node) {
+  if (node == NULL) {
+    return false;
+  }
+  return node->type >= CMARK_NODE_FIRST_BLOCK &&
+         node->type <= CMARK_NODE_LAST_BLOCK;
+}
+
+bool cmark_node_is_inline(cmark_node *node) {
+  if (node == NULL) {
+    return false;
+  }
+  return node->type >= CMARK_NODE_FIRST_INLINE &&
+         node->type <= CMARK_NODE_LAST_INLINE;
+}
+
+bool cmark_node_is_leaf(cmark_node *node) {
+  if (node == NULL) {
+    return false;
+  }
+  switch (node->type) {
+    case CMARK_NODE_THEMATIC_BREAK: return true;
+    case CMARK_NODE_CODE_BLOCK : return true;
+    case CMARK_NODE_TEXT : return true;
+    case CMARK_NODE_SOFTBREAK : return true;
+    case CMARK_NODE_LINEBREAK : return true;
+    case CMARK_NODE_CODE : return true;
+    case CMARK_NODE_HTML_INLINE: return true;
+  }
+  return false;
+}
+
+static bool S_can_contain(cmark_node *node, cmark_node *child) {
+  if (node == NULL || child == NULL || node == child) {
+    return false;
+  }
+
+  // Verify that child is not an ancestor of node.
+  if (child->first_child != NULL) {
+    cmark_node *cur = node->parent;
+
+    while (cur != NULL) {
+      if (cur == child) {
+        return false;
+      }
+      cur = cur->parent;
+    }
+  }
+
+  if (child->type == CMARK_NODE_DOCUMENT) {
+    return false;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_DOCUMENT:
+  case CMARK_NODE_BLOCK_QUOTE:
+  case CMARK_NODE_ITEM:
+    return cmark_node_is_block(child) && child->type != CMARK_NODE_ITEM;
+
+  case CMARK_NODE_LIST:
+    return child->type == CMARK_NODE_ITEM;
+
+  case CMARK_NODE_CUSTOM_BLOCK:
+    return true;
+
+  case CMARK_NODE_PARAGRAPH:
+  case CMARK_NODE_HEADING:
+  case CMARK_NODE_EMPH:
+  case CMARK_NODE_STRONG:
+  case CMARK_NODE_LINK:
+  case CMARK_NODE_IMAGE:
+  case CMARK_NODE_CUSTOM_INLINE:
+    return cmark_node_is_inline(child);
+
+  default:
+    break;
+  }
+
+  return false;
+}
+
+cmark_node *cmark_node_new_with_mem(cmark_node_type type, cmark_mem *mem) {
+  cmark_node *node = (cmark_node *)mem->calloc(1, sizeof(*node));
+  node->mem = mem;
+  node->type = (uint16_t)type;
+
+  switch (node->type) {
+  case CMARK_NODE_HEADING:
+    node->as.heading.level = 1;
+    break;
+
+  case CMARK_NODE_LIST: {
+    cmark_list *list = &node->as.list;
+    list->list_type = CMARK_BULLET_LIST;
+    list->start = 0;
+    list->tight = false;
+    break;
+  }
+
+  default:
+    break;
+  }
+
+  return node;
+}
+
+cmark_node *cmark_node_new(cmark_node_type type) {
+  extern cmark_mem DEFAULT_MEM_ALLOCATOR;
+  return cmark_node_new_with_mem(type, &DEFAULT_MEM_ALLOCATOR);
+}
+
+// Free a cmark_node list and any children.
+static void S_free_nodes(cmark_node *e) {
+  cmark_mem *mem = e->mem;
+  cmark_node *next;
+  while (e != NULL) {
+    switch (e->type) {
+    case CMARK_NODE_CODE_BLOCK:
+      mem->free(e->data);
+      mem->free(e->as.code.info);
+      break;
+    case CMARK_NODE_TEXT:
+    case CMARK_NODE_HTML_INLINE:
+    case CMARK_NODE_CODE:
+    case CMARK_NODE_HTML_BLOCK:
+      mem->free(e->data);
+      break;
+    case CMARK_NODE_LINK:
+    case CMARK_NODE_IMAGE:
+      mem->free(e->as.link.url);
+      mem->free(e->as.link.title);
+      break;
+    case CMARK_NODE_CUSTOM_BLOCK:
+    case CMARK_NODE_CUSTOM_INLINE:
+      mem->free(e->as.custom.on_enter);
+      mem->free(e->as.custom.on_exit);
+      break;
+    default:
+      break;
+    }
+    if (e->last_child) {
+      // Splice children into list
+      e->last_child->next = e->next;
+      e->next = e->first_child;
+    }
+    next = e->next;
+    mem->free(e);
+    e = next;
+  }
+}
+
+void cmark_node_free(cmark_node *node) {
+  S_node_unlink(node);
+  node->next = NULL;
+  S_free_nodes(node);
+}
+
+cmark_node_type cmark_node_get_type(cmark_node *node) {
+  if (node == NULL) {
+    return CMARK_NODE_NONE;
+  } else {
+    return (cmark_node_type)node->type;
+  }
+}
+
+const char *cmark_node_get_type_string(cmark_node *node) {
+  if (node == NULL) {
+    return "NONE";
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_NONE:
+    return "none";
+  case CMARK_NODE_DOCUMENT:
+    return "document";
+  case CMARK_NODE_BLOCK_QUOTE:
+    return "block_quote";
+  case CMARK_NODE_LIST:
+    return "list";
+  case CMARK_NODE_ITEM:
+    return "item";
+  case CMARK_NODE_CODE_BLOCK:
+    return "code_block";
+  case CMARK_NODE_HTML_BLOCK:
+    return "html_block";
+  case CMARK_NODE_CUSTOM_BLOCK:
+    return "custom_block";
+  case CMARK_NODE_PARAGRAPH:
+    return "paragraph";
+  case CMARK_NODE_HEADING:
+    return "heading";
+  case CMARK_NODE_THEMATIC_BREAK:
+    return "thematic_break";
+  case CMARK_NODE_TEXT:
+    return "text";
+  case CMARK_NODE_SOFTBREAK:
+    return "softbreak";
+  case CMARK_NODE_LINEBREAK:
+    return "linebreak";
+  case CMARK_NODE_CODE:
+    return "code";
+  case CMARK_NODE_HTML_INLINE:
+    return "html_inline";
+  case CMARK_NODE_CUSTOM_INLINE:
+    return "custom_inline";
+  case CMARK_NODE_EMPH:
+    return "emph";
+  case CMARK_NODE_STRONG:
+    return "strong";
+  case CMARK_NODE_LINK:
+    return "link";
+  case CMARK_NODE_IMAGE:
+    return "image";
+  }
+
+  return "<unknown>";
+}
+
+cmark_node *cmark_node_next(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  } else {
+    return node->next;
+  }
+}
+
+cmark_node *cmark_node_previous(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  } else {
+    return node->prev;
+  }
+}
+
+cmark_node *cmark_node_parent(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  } else {
+    return node->parent;
+  }
+}
+
+cmark_node *cmark_node_first_child(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  } else {
+    return node->first_child;
+  }
+}
+
+cmark_node *cmark_node_last_child(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  } else {
+    return node->last_child;
+  }
+}
+
+static bufsize_t cmark_set_cstr(cmark_mem *mem, unsigned char **dst,
+                                const char *src) {
+  unsigned char *old = *dst;
+  bufsize_t len;
+
+  if (src && src[0]) {
+      len = (bufsize_t)strlen(src);
+      *dst = (unsigned char *)mem->realloc(NULL, len + 1);
+      memcpy(*dst, src, len + 1);
+  } else {
+      len = 0;
+      *dst = NULL;
+  }
+  if (old) {
+    mem->free(old);
+  }
+
+  return len;
+}
+
+void *cmark_node_get_user_data(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  } else {
+    return node->user_data;
+  }
+}
+
+int cmark_node_set_user_data(cmark_node *node, void *user_data) {
+  if (node == NULL) {
+    return 0;
+  }
+  node->user_data = user_data;
+  return 1;
+}
+
+const char *cmark_node_get_literal(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_HTML_BLOCK:
+  case CMARK_NODE_TEXT:
+  case CMARK_NODE_HTML_INLINE:
+  case CMARK_NODE_CODE:
+  case CMARK_NODE_CODE_BLOCK:
+    return node->data ? (char *)node->data : "";
+
+  default:
+    break;
+  }
+
+  return NULL;
+}
+
+int cmark_node_set_literal(cmark_node *node, const char *content) {
+  if (node == NULL) {
+    return 0;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_HTML_BLOCK:
+  case CMARK_NODE_TEXT:
+  case CMARK_NODE_HTML_INLINE:
+  case CMARK_NODE_CODE:
+  case CMARK_NODE_CODE_BLOCK:
+    node->len = cmark_set_cstr(node->mem, &node->data, content);
+    return 1;
+
+  default:
+    break;
+  }
+
+  return 0;
+}
+
+int cmark_node_get_heading_level(cmark_node *node) {
+  if (node == NULL) {
+    return 0;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_HEADING:
+    return node->as.heading.level;
+
+  default:
+    break;
+  }
+
+  return 0;
+}
+
+int cmark_node_set_heading_level(cmark_node *node, int level) {
+  if (node == NULL || level < 1 || level > 6) {
+    return 0;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_HEADING:
+    node->as.heading.level = level;
+    return 1;
+
+  default:
+    break;
+  }
+
+  return 0;
+}
+
+cmark_list_type cmark_node_get_list_type(cmark_node *node) {
+  if (node == NULL) {
+    return CMARK_NO_LIST;
+  }
+
+  if (node->type == CMARK_NODE_LIST) {
+    return (cmark_list_type)node->as.list.list_type;
+  } else {
+    return CMARK_NO_LIST;
+  }
+}
+
+int cmark_node_set_list_type(cmark_node *node, cmark_list_type type) {
+  if (!(type == CMARK_BULLET_LIST || type == CMARK_ORDERED_LIST)) {
+    return 0;
+  }
+
+  if (node == NULL) {
+    return 0;
+  }
+
+  if (node->type == CMARK_NODE_LIST) {
+    node->as.list.list_type = (unsigned char)type;
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
+cmark_delim_type cmark_node_get_list_delim(cmark_node *node) {
+  if (node == NULL) {
+    return CMARK_NO_DELIM;
+  }
+
+  if (node->type == CMARK_NODE_LIST) {
+    return (cmark_delim_type)node->as.list.delimiter;
+  } else {
+    return CMARK_NO_DELIM;
+  }
+}
+
+int cmark_node_set_list_delim(cmark_node *node, cmark_delim_type delim) {
+  if (!(delim == CMARK_PERIOD_DELIM || delim == CMARK_PAREN_DELIM)) {
+    return 0;
+  }
+
+  if (node == NULL) {
+    return 0;
+  }
+
+  if (node->type == CMARK_NODE_LIST) {
+    node->as.list.delimiter = (unsigned char)delim;
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
+int cmark_node_get_list_start(cmark_node *node) {
+  if (node == NULL) {
+    return 0;
+  }
+
+  if (node->type == CMARK_NODE_LIST) {
+    return node->as.list.start;
+  } else {
+    return 0;
+  }
+}
+
+int cmark_node_set_list_start(cmark_node *node, int start) {
+  if (node == NULL || start < 0) {
+    return 0;
+  }
+
+  if (node->type == CMARK_NODE_LIST) {
+    node->as.list.start = start;
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
+int cmark_node_get_list_tight(cmark_node *node) {
+  if (node == NULL) {
+    return 0;
+  }
+
+  if (node->type == CMARK_NODE_LIST) {
+    return node->as.list.tight;
+  } else {
+    return 0;
+  }
+}
+
+int cmark_node_set_list_tight(cmark_node *node, int tight) {
+  if (node == NULL) {
+    return 0;
+  }
+
+  if (node->type == CMARK_NODE_LIST) {
+    node->as.list.tight = tight == 1;
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
+const char *cmark_node_get_fence_info(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  }
+
+  if (node->type == CMARK_NODE_CODE_BLOCK) {
+    return node->as.code.info ? (char *)node->as.code.info : "";
+  } else {
+    return NULL;
+  }
+}
+
+int cmark_node_set_fence_info(cmark_node *node, const char *info) {
+  if (node == NULL) {
+    return 0;
+  }
+
+  if (node->type == CMARK_NODE_CODE_BLOCK) {
+    cmark_set_cstr(node->mem, &node->as.code.info, info);
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
+const char *cmark_node_get_url(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_LINK:
+  case CMARK_NODE_IMAGE:
+    return node->as.link.url ? (char *)node->as.link.url : "";
+  default:
+    break;
+  }
+
+  return NULL;
+}
+
+int cmark_node_set_url(cmark_node *node, const char *url) {
+  if (node == NULL) {
+    return 0;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_LINK:
+  case CMARK_NODE_IMAGE:
+    cmark_set_cstr(node->mem, &node->as.link.url, url);
+    return 1;
+  default:
+    break;
+  }
+
+  return 0;
+}
+
+const char *cmark_node_get_title(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_LINK:
+  case CMARK_NODE_IMAGE:
+    return node->as.link.title ? (char *)node->as.link.title : "";
+  default:
+    break;
+  }
+
+  return NULL;
+}
+
+int cmark_node_set_title(cmark_node *node, const char *title) {
+  if (node == NULL) {
+    return 0;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_LINK:
+  case CMARK_NODE_IMAGE:
+    cmark_set_cstr(node->mem, &node->as.link.title, title);
+    return 1;
+  default:
+    break;
+  }
+
+  return 0;
+}
+
+const char *cmark_node_get_on_enter(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_CUSTOM_INLINE:
+  case CMARK_NODE_CUSTOM_BLOCK:
+    return node->as.custom.on_enter ? (char *)node->as.custom.on_enter : "";
+  default:
+    break;
+  }
+
+  return NULL;
+}
+
+int cmark_node_set_on_enter(cmark_node *node, const char *on_enter) {
+  if (node == NULL) {
+    return 0;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_CUSTOM_INLINE:
+  case CMARK_NODE_CUSTOM_BLOCK:
+    cmark_set_cstr(node->mem, &node->as.custom.on_enter, on_enter);
+    return 1;
+  default:
+    break;
+  }
+
+  return 0;
+}
+
+const char *cmark_node_get_on_exit(cmark_node *node) {
+  if (node == NULL) {
+    return NULL;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_CUSTOM_INLINE:
+  case CMARK_NODE_CUSTOM_BLOCK:
+    return node->as.custom.on_exit ? (char *)node->as.custom.on_exit : "";
+  default:
+    break;
+  }
+
+  return NULL;
+}
+
+int cmark_node_set_on_exit(cmark_node *node, const char *on_exit) {
+  if (node == NULL) {
+    return 0;
+  }
+
+  switch (node->type) {
+  case CMARK_NODE_CUSTOM_INLINE:
+  case CMARK_NODE_CUSTOM_BLOCK:
+    cmark_set_cstr(node->mem, &node->as.custom.on_exit, on_exit);
+    return 1;
+  default:
+    break;
+  }
+
+  return 0;
+}
+
+int cmark_node_get_start_line(cmark_node *node) {
+  if (node == NULL) {
+    return 0;
+  }
+  return node->start_line;
+}
+
+int cmark_node_get_start_column(cmark_node *node) {
+  if (node == NULL) {
+    return 0;
+  }
+  return node->start_column;
+}
+
+int cmark_node_get_end_line(cmark_node *node) {
+  if (node == NULL) {
+    return 0;
+  }
+  return node->end_line;
+}
+
+int cmark_node_get_end_column(cmark_node *node) {
+  if (node == NULL) {
+    return 0;
+  }
+  return node->end_column;
+}
+
+// Unlink a node without adjusting its next, prev, and parent pointers.
+static void S_node_unlink(cmark_node *node) {
+  if (node == NULL) {
+    return;
+  }
+
+  if (node->prev) {
+    node->prev->next = node->next;
+  }
+  if (node->next) {
+    node->next->prev = node->prev;
+  }
+
+  // Adjust first_child and last_child of parent.
+  cmark_node *parent = node->parent;
+  if (parent) {
+    if (parent->first_child == node) {
+      parent->first_child = node->next;
+    }
+    if (parent->last_child == node) {
+      parent->last_child = node->prev;
+    }
+  }
+}
+
+void cmark_node_unlink(cmark_node *node) {
+  S_node_unlink(node);
+
+  node->next = NULL;
+  node->prev = NULL;
+  node->parent = NULL;
+}
+
+int cmark_node_insert_before(cmark_node *node, cmark_node *sibling) {
+  if (node == NULL || sibling == NULL) {
+    return 0;
+  }
+
+  if (!node->parent || !S_can_contain(node->parent, sibling)) {
+    return 0;
+  }
+
+  S_node_unlink(sibling);
+
+  cmark_node *old_prev = node->prev;
+
+  // Insert 'sibling' between 'old_prev' and 'node'.
+  if (old_prev) {
+    old_prev->next = sibling;
+  }
+  sibling->prev = old_prev;
+  sibling->next = node;
+  node->prev = sibling;
+
+  // Set new parent.
+  cmark_node *parent = node->parent;
+  sibling->parent = parent;
+
+  // Adjust first_child of parent if inserted as first child.
+  if (parent && !old_prev) {
+    parent->first_child = sibling;
+  }
+
+  return 1;
+}
+
+int cmark_node_insert_after(cmark_node *node, cmark_node *sibling) {
+  if (node == NULL || sibling == NULL) {
+    return 0;
+  }
+
+  if (!node->parent || !S_can_contain(node->parent, sibling)) {
+    return 0;
+  }
+
+  S_node_unlink(sibling);
+
+  cmark_node *old_next = node->next;
+
+  // Insert 'sibling' between 'node' and 'old_next'.
+  if (old_next) {
+    old_next->prev = sibling;
+  }
+  sibling->next = old_next;
+  sibling->prev = node;
+  node->next = sibling;
+
+  // Set new parent.
+  cmark_node *parent = node->parent;
+  sibling->parent = parent;
+
+  // Adjust last_child of parent if inserted as last child.
+  if (parent && !old_next) {
+    parent->last_child = sibling;
+  }
+
+  return 1;
+}
+
+int cmark_node_replace(cmark_node *oldnode, cmark_node *newnode) {
+  if (!cmark_node_insert_before(oldnode, newnode)) {
+    return 0;
+  }
+  cmark_node_unlink(oldnode);
+  return 1;
+}
+
+int cmark_node_prepend_child(cmark_node *node, cmark_node *child) {
+  if (!S_can_contain(node, child)) {
+    return 0;
+  }
+
+  S_node_unlink(child);
+
+  cmark_node *old_first_child = node->first_child;
+
+  child->next = old_first_child;
+  child->prev = NULL;
+  child->parent = node;
+  node->first_child = child;
+
+  if (old_first_child) {
+    old_first_child->prev = child;
+  } else {
+    // Also set last_child if node previously had no children.
+    node->last_child = child;
+  }
+
+  return 1;
+}
+
+int cmark_node_append_child(cmark_node *node, cmark_node *child) {
+  if (!S_can_contain(node, child)) {
+    return 0;
+  }
+
+  S_node_unlink(child);
+
+  cmark_node *old_last_child = node->last_child;
+
+  child->next = NULL;
+  child->prev = old_last_child;
+  child->parent = node;
+  node->last_child = child;
+
+  if (old_last_child) {
+    old_last_child->next = child;
+  } else {
+    // Also set first_child if node previously had no children.
+    node->first_child = child;
+  }
+
+  return 1;
+}
+
+static void S_print_error(FILE *out, cmark_node *node, const char *elem) {
+  if (out == NULL) {
+    return;
+  }
+  fprintf(out, "Invalid '%s' in node type %s at %d:%d\n", elem,
+          cmark_node_get_type_string(node), node->start_line,
+          node->start_column);
+}
+
+int cmark_node_check(cmark_node *node, FILE *out) {
+  cmark_node *cur;
+  int errors = 0;
+
+  if (!node) {
+    return 0;
+  }
+
+  cur = node;
+  for (;;) {
+    if (cur->first_child) {
+      if (cur->first_child->prev != NULL) {
+        S_print_error(out, cur->first_child, "prev");
+        cur->first_child->prev = NULL;
+        ++errors;
+      }
+      if (cur->first_child->parent != cur) {
+        S_print_error(out, cur->first_child, "parent");
+        cur->first_child->parent = cur;
+        ++errors;
+      }
+      cur = cur->first_child;
+      continue;
+    }
+
+  next_sibling:
+    if (cur == node) {
+      break;
+    }
+    if (cur->next) {
+      if (cur->next->prev != cur) {
+        S_print_error(out, cur->next, "prev");
+        cur->next->prev = cur;
+        ++errors;
+      }
+      if (cur->next->parent != cur->parent) {
+        S_print_error(out, cur->next, "parent");
+        cur->next->parent = cur->parent;
+        ++errors;
+      }
+      cur = cur->next;
+      continue;
+    }
+
+    if (cur->parent->last_child != cur) {
+      S_print_error(out, cur->parent, "last_child");
+      cur->parent->last_child = cur;
+      ++errors;
+    }
+    cur = cur->parent;
+    goto next_sibling;
+  }
+
+  return errors;
+}