Add 'cmark/' from commit '64efa3b3b3d35f2ffb604b57a8a9c89047cb420b'

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

1 files changed, 209 insertions, 0 deletions

diff --git a/cmark/src/buffer.c b/cmark/src/buffer.c
new file mode 100644
index 0000000000..f3159948ce
--- /dev/null
+++ b/cmark/src/buffer.c
@@ -0,0 +1,209 @@
+#include <assert.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "cmark_ctype.h"
+#include "buffer.h"
+
+/* Used as default value for cmark_strbuf->ptr so that people can always
+ * assume ptr is non-NULL and zero terminated even for new cmark_strbufs.
+ */
+unsigned char cmark_strbuf__initbuf[1];
+
+#ifndef MIN
+#define MIN(x, y) ((x < y) ? x : y)
+#endif
+
+void cmark_strbuf_init(cmark_mem *mem, cmark_strbuf *buf,
+                       bufsize_t initial_size) {
+  buf->mem = mem;
+  buf->asize = 0;
+  buf->size = 0;
+  buf->ptr = cmark_strbuf__initbuf;
+
+  if (initial_size > 0)
+    cmark_strbuf_grow(buf, initial_size);
+}
+
+static inline void S_strbuf_grow_by(cmark_strbuf *buf, bufsize_t add) {
+  cmark_strbuf_grow(buf, buf->size + add);
+}
+
+void cmark_strbuf_grow(cmark_strbuf *buf, bufsize_t target_size) {
+  assert(target_size > 0);
+
+  if (target_size < buf->asize)
+    return;
+
+  if (target_size > (bufsize_t)(INT32_MAX / 2)) {
+    fprintf(stderr,
+      "[cmark] cmark_strbuf_grow requests buffer with size > %d, aborting\n",
+         (INT32_MAX / 2));
+    abort();
+  }
+
+  /* Oversize the buffer by 50% to guarantee amortized linear time
+   * complexity on append operations. */
+  bufsize_t new_size = target_size + target_size / 2;
+  new_size += 1;
+  new_size = (new_size + 7) & ~7;
+
+  buf->ptr = (unsigned char *)buf->mem->realloc(buf->asize ? buf->ptr : NULL,
+                                                new_size);
+  buf->asize = new_size;
+}
+
+void cmark_strbuf_free(cmark_strbuf *buf) {
+  if (!buf)
+    return;
+
+  if (buf->ptr != cmark_strbuf__initbuf)
+    buf->mem->free(buf->ptr);
+
+  cmark_strbuf_init(buf->mem, buf, 0);
+}
+
+void cmark_strbuf_clear(cmark_strbuf *buf) {
+  buf->size = 0;
+
+  if (buf->asize > 0)
+    buf->ptr[0] = '\0';
+}
+
+void cmark_strbuf_set(cmark_strbuf *buf, const unsigned char *data,
+                      bufsize_t len) {
+  if (len <= 0 || data == NULL) {
+    cmark_strbuf_clear(buf);
+  } else {
+    if (data != buf->ptr) {
+      if (len >= buf->asize)
+        cmark_strbuf_grow(buf, len);
+      memmove(buf->ptr, data, len);
+    }
+    buf->size = len;
+    buf->ptr[buf->size] = '\0';
+  }
+}
+
+void cmark_strbuf_putc(cmark_strbuf *buf, int c) {
+  S_strbuf_grow_by(buf, 1);
+  buf->ptr[buf->size++] = (unsigned char)(c & 0xFF);
+  buf->ptr[buf->size] = '\0';
+}
+
+void cmark_strbuf_put(cmark_strbuf *buf, const unsigned char *data,
+                      bufsize_t len) {
+  if (len <= 0)
+    return;
+
+  S_strbuf_grow_by(buf, len);
+  memmove(buf->ptr + buf->size, data, len);
+  buf->size += len;
+  buf->ptr[buf->size] = '\0';
+}
+
+void cmark_strbuf_puts(cmark_strbuf *buf, const char *string) {
+  cmark_strbuf_put(buf, (const unsigned char *)string, (bufsize_t)strlen(string));
+}
+
+unsigned char *cmark_strbuf_detach(cmark_strbuf *buf) {
+  unsigned char *data = buf->ptr;
+
+  if (buf->asize == 0) {
+    /* return an empty string */
+    return (unsigned char *)buf->mem->calloc(1, 1);
+  }
+
+  cmark_strbuf_init(buf->mem, buf, 0);
+  return data;
+}
+
+void cmark_strbuf_truncate(cmark_strbuf *buf, bufsize_t len) {
+  if (len < 0)
+    len = 0;
+
+  if (len < buf->size) {
+    buf->size = len;
+    buf->ptr[buf->size] = '\0';
+  }
+}
+
+void cmark_strbuf_drop(cmark_strbuf *buf, bufsize_t n) {
+  if (n > 0) {
+    if (n > buf->size)
+      n = buf->size;
+    buf->size = buf->size - n;
+    if (buf->size)
+      memmove(buf->ptr, buf->ptr + n, buf->size);
+
+    buf->ptr[buf->size] = '\0';
+  }
+}
+
+void cmark_strbuf_rtrim(cmark_strbuf *buf) {
+  if (!buf->size)
+    return;
+
+  while (buf->size > 0) {
+    if (!cmark_isspace(buf->ptr[buf->size - 1]))
+      break;
+
+    buf->size--;
+  }
+
+  buf->ptr[buf->size] = '\0';
+}
+
+void cmark_strbuf_trim(cmark_strbuf *buf) {
+  bufsize_t i = 0;
+
+  if (!buf->size)
+    return;
+
+  while (i < buf->size && cmark_isspace(buf->ptr[i]))
+    i++;
+
+  cmark_strbuf_drop(buf, i);
+
+  cmark_strbuf_rtrim(buf);
+}
+
+// Destructively modify string, collapsing consecutive
+// space and newline characters into a single space.
+void cmark_strbuf_normalize_whitespace(cmark_strbuf *s) {
+  bool last_char_was_space = false;
+  bufsize_t r, w;
+
+  for (r = 0, w = 0; r < s->size; ++r) {
+    if (cmark_isspace(s->ptr[r])) {
+      if (!last_char_was_space) {
+        s->ptr[w++] = ' ';
+        last_char_was_space = true;
+      }
+    } else {
+      s->ptr[w++] = s->ptr[r];
+      last_char_was_space = false;
+    }
+  }
+
+  cmark_strbuf_truncate(s, w);
+}
+
+// Destructively unescape a string: remove backslashes before punctuation chars.
+void cmark_strbuf_unescape(cmark_strbuf *buf) {
+  bufsize_t r, w;
+
+  for (r = 0, w = 0; r < buf->size; ++r) {
+    if (buf->ptr[r] == '\\' && cmark_ispunct(buf->ptr[r + 1]))
+      r++;
+
+    buf->ptr[w++] = buf->ptr[r];
+  }
+
+  cmark_strbuf_truncate(buf, w);
+}