1 files changed, 115 insertions, 0 deletions
diff --git a/externals/breakpad/src/common/linux/memory_mapped_file.cc b/externals/breakpad/src/common/linux/memory_mapped_file.cc
new file mode 100644
index 0000000000..a7b96eb591
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+++ b/externals/breakpad/src/common/linux/memory_mapped_file.cc
@@ -0,0 +1,115 @@
+// Copyright 2011 Google LLC
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google LLC nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// memory_mapped_file.cc: Implement google_breakpad::MemoryMappedFile.
+// See memory_mapped_file.h for details.
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>  // Must come first
+#endif
+
+#include "common/linux/memory_mapped_file.h"
+
+#include <fcntl.h>
+#include <sys/mman.h>
+#if defined(__ANDROID__)
+#include <sys/stat.h>
+#endif
+#include <unistd.h>
+
+#include "common/memory_range.h"
+#include "third_party/lss/linux_syscall_support.h"
+
+namespace google_breakpad {
+
+MemoryMappedFile::MemoryMappedFile() {}
+
+MemoryMappedFile::MemoryMappedFile(const char* path, size_t offset) {
+  Map(path, offset);
+}
+
+MemoryMappedFile::~MemoryMappedFile() {
+  Unmap();
+}
+
+#include <unistd.h>
+
+bool MemoryMappedFile::Map(const char* path, size_t offset) {
+  Unmap();
+  // Based on https://pubs.opengroup.org/onlinepubs/7908799/xsh/open.html
+  // If O_NONBLOCK is set: The open() function will return without blocking
+  // for the device to be ready or available. Setting this value will provent
+  // hanging if file is not avilable.
+  int fd = sys_open(path, O_RDONLY | O_NONBLOCK, 0);
+  if (fd == -1) {
+    return false;
+  }
+
+#if defined(__x86_64__) || defined(__aarch64__) || \
+   (defined(__mips__) && _MIPS_SIM == _ABI64) || \
+   (defined(__riscv) && __riscv_xlen == 64)
+
+  struct kernel_stat st;
+  if (sys_fstat(fd, &st) == -1 || st.st_size < 0) {
+#else
+  struct kernel_stat64 st;
+  if (sys_fstat64(fd, &st) == -1 || st.st_size < 0) {
+#endif
+    sys_close(fd);
+    return false;
+  }
+
+  // Strangely file size can be negative, but we check above that it is not.
+  size_t file_len = static_cast<size_t>(st.st_size);
+  // If the file does not extend beyond the offset, simply use an empty
+  // MemoryRange and return true. Don't bother to call mmap()
+  // even though mmap() can handle an empty file on some platforms.
+  if (offset >= file_len) {
+    sys_close(fd);
+    return true;
+  }
+
+  size_t content_len = file_len - offset;
+  void* data = sys_mmap(NULL, content_len, PROT_READ, MAP_PRIVATE, fd, offset);
+  sys_close(fd);
+  if (data == MAP_FAILED) {
+    return false;
+  }
+
+  content_.Set(data, content_len);
+  return true;
+}
+
+void MemoryMappedFile::Unmap() {
+  if (content_.data()) {
+    sys_munmap(const_cast<uint8_t*>(content_.data()), content_.length());
+    content_.Set(NULL, 0);
+  }
+}
+
+}  // namespace google_breakpad