Add 'cmark/' from commit '64efa3b3b3d35f2ffb604b57a8a9c89047cb420b'

git-subtree-dir: cmark
git-subtree-mainline: 6bf7c5ce92ff6237c0b17c332873805018812b40
git-subtree-split: 64efa3b3b3d35f2ffb604b57a8a9c89047cb420b

1 files changed, 195 insertions, 0 deletions

diff --git a/cmark/src/render.c b/cmark/src/render.c
new file mode 100644
index 0000000000..0404deba15
--- /dev/null
+++ b/cmark/src/render.c
@@ -0,0 +1,195 @@
+#include <stdlib.h>
+#include "buffer.h"
+#include "cmark.h"
+#include "utf8.h"
+#include "render.h"
+#include "node.h"
+#include "cmark_ctype.h"
+
+static inline void S_cr(cmark_renderer *renderer) {
+  if (renderer->need_cr < 1) {
+    renderer->need_cr = 1;
+  }
+}
+
+static inline void S_blankline(cmark_renderer *renderer) {
+  if (renderer->need_cr < 2) {
+    renderer->need_cr = 2;
+  }
+}
+
+static void S_out(cmark_renderer *renderer, const char *source, bool wrap,
+                  cmark_escaping escape) {
+  int length = (int)strlen(source);
+  unsigned char nextc;
+  int32_t c;
+  int i = 0;
+  int last_nonspace;
+  int len;
+  int k = renderer->buffer->size - 1;
+
+  wrap = wrap && !renderer->no_linebreaks;
+
+  if (renderer->in_tight_list_item && renderer->need_cr > 1) {
+    renderer->need_cr = 1;
+  }
+  while (renderer->need_cr) {
+    if (k < 0 || renderer->buffer->ptr[k] == '\n') {
+      k -= 1;
+    } else {
+      cmark_strbuf_putc(renderer->buffer, '\n');
+      if (renderer->need_cr > 1) {
+        cmark_strbuf_put(renderer->buffer, renderer->prefix->ptr,
+                         renderer->prefix->size);
+      }
+    }
+    renderer->column = 0;
+    renderer->last_breakable = 0;
+    renderer->begin_line = true;
+    renderer->begin_content = true;
+    renderer->need_cr -= 1;
+  }
+
+  while (i < length) {
+    if (renderer->begin_line) {
+      cmark_strbuf_put(renderer->buffer, renderer->prefix->ptr,
+                       renderer->prefix->size);
+      // note: this assumes prefix is ascii:
+      renderer->column = renderer->prefix->size;
+    }
+
+    len = cmark_utf8proc_iterate((const uint8_t *)source + i, length - i, &c);
+    if (len == -1) { // error condition
+      return;        // return without rendering rest of string
+    }
+    nextc = source[i + len];
+    if (c == 32 && wrap) {
+      if (!renderer->begin_line) {
+        last_nonspace = renderer->buffer->size;
+        cmark_strbuf_putc(renderer->buffer, ' ');
+        renderer->column += 1;
+        renderer->begin_line = false;
+        renderer->begin_content = false;
+        // skip following spaces
+        while (source[i + 1] == ' ') {
+          i++;
+        }
+        // We don't allow breaks that make a digit the first character
+        // because this causes problems with commonmark output.
+        if (!cmark_isdigit(source[i + 1])) {
+          renderer->last_breakable = last_nonspace;
+        }
+      }
+
+    } else if (escape == LITERAL) {
+      if (c == 10) {
+        cmark_strbuf_putc(renderer->buffer, '\n');
+        renderer->column = 0;
+        renderer->begin_line = true;
+        renderer->begin_content = true;
+        renderer->last_breakable = 0;
+      } else {
+        cmark_render_code_point(renderer, c);
+        renderer->begin_line = false;
+        // we don't set 'begin_content' to false til we've
+        // finished parsing a digit.  Reason:  in commonmark
+        // we need to escape a potential list marker after
+        // a digit:
+        renderer->begin_content =
+            renderer->begin_content && cmark_isdigit(c) == 1;
+      }
+    } else {
+      (renderer->outc)(renderer, escape, c, nextc);
+      renderer->begin_line = false;
+      renderer->begin_content =
+          renderer->begin_content && cmark_isdigit(c) == 1;
+    }
+
+    // If adding the character went beyond width, look for an
+    // earlier place where the line could be broken:
+    if (renderer->width > 0 && renderer->column > renderer->width &&
+        !renderer->begin_line && renderer->last_breakable > 0) {
+
+      // copy from last_breakable to remainder
+      unsigned char *src = renderer->buffer->ptr +
+                           renderer->last_breakable + 1;
+      bufsize_t remainder_len = renderer->buffer->size -
+                                renderer->last_breakable - 1;
+      unsigned char *remainder =
+          (unsigned char *)renderer->mem->realloc(NULL, remainder_len);
+      memcpy(remainder, src, remainder_len);
+      // truncate at last_breakable
+      cmark_strbuf_truncate(renderer->buffer, renderer->last_breakable);
+      // add newline, prefix, and remainder
+      cmark_strbuf_putc(renderer->buffer, '\n');
+      cmark_strbuf_put(renderer->buffer, renderer->prefix->ptr,
+                       renderer->prefix->size);
+      cmark_strbuf_put(renderer->buffer, remainder, remainder_len);
+      renderer->column = renderer->prefix->size + remainder_len;
+      renderer->mem->free(remainder);
+      renderer->last_breakable = 0;
+      renderer->begin_line = false;
+      renderer->begin_content = false;
+    }
+
+    i += len;
+  }
+}
+
+// Assumes no newlines, assumes ascii content:
+void cmark_render_ascii(cmark_renderer *renderer, const char *s) {
+  int origsize = renderer->buffer->size;
+  cmark_strbuf_puts(renderer->buffer, s);
+  renderer->column += renderer->buffer->size - origsize;
+}
+
+void cmark_render_code_point(cmark_renderer *renderer, uint32_t c) {
+  cmark_utf8proc_encode_char(c, renderer->buffer);
+  renderer->column += 1;
+}
+
+char *cmark_render(cmark_node *root, int options, int width,
+                   void (*outc)(cmark_renderer *, cmark_escaping, int32_t,
+                                unsigned char),
+                   int (*render_node)(cmark_renderer *renderer,
+                                      cmark_node *node,
+                                      cmark_event_type ev_type, int options)) {
+  cmark_mem *mem = root->mem;
+  cmark_strbuf pref = CMARK_BUF_INIT(mem);
+  cmark_strbuf buf = CMARK_BUF_INIT(mem);
+  cmark_node *cur;
+  cmark_event_type ev_type;
+  char *result;
+  cmark_iter *iter = cmark_iter_new(root);
+
+  cmark_renderer renderer = {options,
+                             mem,    &buf,    &pref,      0,      width,
+                             0,      0,       true,       true,   false,
+                             false,  NULL,
+                             outc,   S_cr,    S_blankline, S_out};
+
+  while ((ev_type = cmark_iter_next(iter)) != CMARK_EVENT_DONE) {
+    cur = cmark_iter_get_node(iter);
+    if (!render_node(&renderer, cur, ev_type, options)) {
+      // a false value causes us to skip processing
+      // the node's contents.  this is used for
+      // autolinks.
+      cmark_iter_reset(iter, cur, CMARK_EVENT_EXIT);
+    }
+  }
+
+  // If the root node is a block type (i.e. not inline), ensure there's a final newline:
+  if (cmark_node_is_block(root)) {
+    if (renderer.buffer->size == 0 || renderer.buffer->ptr[renderer.buffer->size - 1] != '\n') {
+      cmark_strbuf_putc(renderer.buffer, '\n');
+    }
+  }
+
+  result = (char *)cmark_strbuf_detach(renderer.buffer);
+
+  cmark_iter_free(iter);
+  cmark_strbuf_free(renderer.prefix);
+  cmark_strbuf_free(renderer.buffer);
+
+  return result;
+}