harfbuzz: check in harfbuzz-ng, add gyp define to use it

third_party/harfbuzz-ng/src/hb-blob.c

+/*
+ * Copyright (C) 2009  Red Hat, Inc.
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Red Hat Author(s): Behdad Esfahbod
+ */
+
+#include "hb-private.h"
+
+#include "hb-blob-private.h"
+
+#ifdef HAVE_SYS_MMAN_H
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif /* HAVE_UNISTD_H */
+#include <sys/mman.h>
+#endif /* HAVE_SYS_MMAN_H */
+
+#include <stdio.h>
+#include <errno.h>
+
+HB_BEGIN_DECLS
+
+
+#ifndef HB_DEBUG_BLOB
+#define HB_DEBUG_BLOB (HB_DEBUG+0)
+#endif
+
+hb_blob_t _hb_blob_nil = {
+  HB_REFERENCE_COUNT_INVALID, /* ref_count */
+
+  0, /* length */
+
+  HB_MUTEX_INIT, /* lock */
+
+  0, /* lock_count */
+  HB_MEMORY_MODE_READONLY, /* mode */
+
+  NULL, /* data */
+
+  NULL, /* destroy */
+  NULL /* user_data */
+};
+
+static void
+_hb_blob_destroy_user_data (hb_blob_t *blob)
+{
+  if (blob->destroy) {
+    blob->destroy (blob->user_data);
+    blob->destroy = NULL;
+    blob->user_data = NULL;
+  }
+}
+
+static void
+_hb_blob_unlock_and_destroy (hb_blob_t *blob)
+{
+  hb_blob_unlock (blob);
+  hb_blob_destroy (blob);
+}
+
+hb_blob_t *
+hb_blob_create (const char        *data,
+                unsigned int       length,
+                hb_memory_mode_t   mode,
+                hb_destroy_func_t  destroy,
+                void              *user_data)
+{
+  hb_blob_t *blob;
+
+  if (!length || !HB_OBJECT_DO_CREATE (hb_blob_t, blob)) {
+    if (destroy)
+      destroy (user_data);
+    return &_hb_blob_nil;
+  }
+
+  hb_mutex_init (blob->lock);
+  blob->lock_count = 0;
+
+  blob->data = data;
+  blob->length = length;
+  blob->mode = mode;
+
+  blob->destroy = destroy;
+  blob->user_data = user_data;
+
+  if (blob->mode == HB_MEMORY_MODE_DUPLICATE) {
+    blob->mode = HB_MEMORY_MODE_READONLY;
+    if (!hb_blob_try_writable (blob)) {
+      hb_blob_destroy (blob);
+      return &_hb_blob_nil;
+    }
+  }
+
+  return blob;
+}
+
+hb_blob_t *
+hb_blob_create_sub_blob (hb_blob_t    *parent,
+                         unsigned int  offset,
+                         unsigned int  length)
+{
+  hb_blob_t *blob;
+  const char *pdata;
+
+  if (!length || offset >= parent->length || !HB_OBJECT_DO_CREATE (hb_blob_t, blob))
+    return &_hb_blob_nil;
+
+  pdata = hb_blob_lock (parent);
+
+  blob->data = pdata + offset;
+  blob->length = MIN (length, parent->length - offset);
+
+  hb_mutex_lock (parent->lock);
+  blob->mode = parent->mode;
+  hb_mutex_unlock (parent->lock);
+
+  blob->destroy = (hb_destroy_func_t) _hb_blob_unlock_and_destroy;
+  blob->user_data = hb_blob_reference (parent);
+
+  return blob;
+}
+
+hb_blob_t *
+hb_blob_create_empty (void)
+{
+  return &_hb_blob_nil;
+}
+
+hb_blob_t *
+hb_blob_reference (hb_blob_t *blob)
+{
+  HB_OBJECT_DO_REFERENCE (blob);
+}
+
+unsigned int
+hb_blob_get_reference_count (hb_blob_t *blob)
+{
+  HB_OBJECT_DO_GET_REFERENCE_COUNT (blob);
+}
+
+void
+hb_blob_destroy (hb_blob_t *blob)
+{
+  HB_OBJECT_DO_DESTROY (blob);
+
+  _hb_blob_destroy_user_data (blob);
+
+  free (blob);
+}
+
+unsigned int
+hb_blob_get_length (hb_blob_t *blob)
+{
+  return blob->length;
+}
+
+const char *
+hb_blob_lock (hb_blob_t *blob)
+{
+  if (HB_OBJECT_IS_INERT (blob))
+    return NULL;
+
+  hb_mutex_lock (blob->lock);
+
+  (void) (HB_DEBUG_BLOB &&
+    fprintf (stderr, "%p %s (%d) -> %p\n", blob, __FUNCTION__,
+             blob->lock_count, blob->data));
+
+  blob->lock_count++;
+
+  hb_mutex_unlock (blob->lock);
+
+  return blob->data;
+}
+
+void
+hb_blob_unlock (hb_blob_t *blob)
+{
+  if (HB_OBJECT_IS_INERT (blob))
+    return;
+
+  hb_mutex_lock (blob->lock);
+
+  (void) (HB_DEBUG_BLOB &&
+    fprintf (stderr, "%p %s (%d) -> %p\n", blob, __FUNCTION__,
+             blob->lock_count, blob->data));
+
+  assert (blob->lock_count > 0);
+  blob->lock_count--;
+
+  hb_mutex_unlock (blob->lock);
+}
+
+hb_bool_t
+hb_blob_is_writable (hb_blob_t *blob)
+{
+  hb_memory_mode_t mode;
+
+  if (HB_OBJECT_IS_INERT (blob))
+    return FALSE;
+
+  hb_mutex_lock (blob->lock);
+
+  mode = blob->mode;
+
+  hb_mutex_unlock (blob->lock);
+
+  return mode == HB_MEMORY_MODE_WRITABLE;
+}
+
+
+static hb_bool_t
+_try_make_writable_inplace_unix_locked (hb_blob_t *blob)
+{
+#if defined(HAVE_SYS_MMAN_H) && defined(HAVE_MPROTECT)
+  uintptr_t pagesize = -1, mask, length;
+  const char *addr;
+
+#if defined(HAVE_SYSCONF) && defined(_SC_PAGE_SIZE)
+  pagesize = (uintptr_t) sysconf (_SC_PAGE_SIZE);
+#elif defined(HAVE_SYSCONF) && defined(_SC_PAGESIZE)
+  pagesize = (uintptr_t) sysconf (_SC_PAGESIZE);
+#elif defined(HAVE_GETPAGESIZE)
+  pagesize = (uintptr_t) getpagesize ();
+#endif
+
+  if ((uintptr_t) -1L == pagesize) {
+    (void) (HB_DEBUG_BLOB &&
+      fprintf (stderr, "%p %s: failed to get pagesize: %s\n", blob, __FUNCTION__, strerror (errno)));
+    return FALSE;
+  }
+  (void) (HB_DEBUG_BLOB &&
+    fprintf (stderr, "%p %s: pagesize is %lu\n", blob, __FUNCTION__, (unsigned long) pagesize));
+
+  mask = ~(pagesize-1);
+  addr = (const char *) (((uintptr_t) blob->data) & mask);
+  length = (const char *) (((uintptr_t) blob->data + blob->length + pagesize-1) & mask)  - addr;
+  (void) (HB_DEBUG_BLOB &&
+    fprintf (stderr, "%p %s: calling mprotect on [%p..%p] (%lu bytes)\n",
+             blob, __FUNCTION__,
+             addr, addr+length, (unsigned long) length));
+  if (-1 == mprotect ((void *) addr, length, PROT_READ | PROT_WRITE)) {
+    (void) (HB_DEBUG_BLOB &&
+      fprintf (stderr, "%p %s: %s\n", blob, __FUNCTION__, strerror (errno)));
+    return FALSE;
+  }
+
+  (void) (HB_DEBUG_BLOB &&
+    fprintf (stderr, "%p %s: successfully made [%p..%p] (%lu bytes) writable\n",
+             blob, __FUNCTION__,
+             addr, addr+length, (unsigned long) length));
+  return TRUE;
+#else
+  return FALSE;
+#endif
+}
+
+static void
+try_writable_inplace_locked (hb_blob_t *blob)
+{
+  (void) (HB_DEBUG_BLOB &&
+    fprintf (stderr, "%p %s: making writable\n", blob, __FUNCTION__));
+
+  if (_try_make_writable_inplace_unix_locked (blob)) {
+    (void) (HB_DEBUG_BLOB &&
+      fprintf (stderr, "%p %s: making writable -> succeeded\n", blob, __FUNCTION__));
+    blob->mode = HB_MEMORY_MODE_WRITABLE;
+  } else {
+    (void) (HB_DEBUG_BLOB &&
+      fprintf (stderr, "%p %s: making writable -> FAILED\n", blob, __FUNCTION__));
+    /* Failed to make writable inplace, mark that */
+    blob->mode = HB_MEMORY_MODE_READONLY;
+  }
+}
+
+hb_bool_t
+hb_blob_try_writable_inplace (hb_blob_t *blob)
+{
+  hb_memory_mode_t mode;
+
+  if (HB_OBJECT_IS_INERT (blob))
+    return FALSE;
+
+  hb_mutex_lock (blob->lock);
+
+  if (blob->mode == HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE)
+    try_writable_inplace_locked (blob);
+
+  mode = blob->mode;
+
+  hb_mutex_unlock (blob->lock);
+
+  return mode == HB_MEMORY_MODE_WRITABLE;
+}
+
+hb_bool_t
+hb_blob_try_writable (hb_blob_t *blob)
+{
+  hb_memory_mode_t mode;
+
+  if (HB_OBJECT_IS_INERT (blob))
+    return FALSE;
+
+  hb_mutex_lock (blob->lock);
+
+  if (blob->mode == HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE)
+    try_writable_inplace_locked (blob);
+
+  if (blob->mode == HB_MEMORY_MODE_READONLY)
+  {
+    char *new_data;
+
+    (void) (HB_DEBUG_BLOB &&
+      fprintf (stderr, "%p %s (%d) -> %p\n", blob, __FUNCTION__,
+               blob->lock_count, blob->data));
+
+    if (blob->lock_count)
+      goto done;
+
+    new_data = malloc (blob->length);
+    if (new_data) {
+      (void) (HB_DEBUG_BLOB &&
+        fprintf (stderr, "%p %s: dupped successfully -> %p\n", blob, __FUNCTION__, blob->data));
+      memcpy (new_data, blob->data, blob->length);
+      _hb_blob_destroy_user_data (blob);
+      blob->mode = HB_MEMORY_MODE_WRITABLE;
+      blob->data = new_data;
+      blob->destroy = free;
+      blob->user_data = new_data;
+    }
+  }
+
+done:
+  mode = blob->mode;
+
+  hb_mutex_unlock (blob->lock);
+
+  return mode == HB_MEMORY_MODE_WRITABLE;
+}
+
+
+HB_END_DECLS