X-Git-Url: https://gerrit.akraino.org/r/gitweb?a=blobdiff_plain;f=src%2Ftype3_AndroidCloud%2Fanbox-master%2Fexternal%2Fcpu_features%2Fsrc%2Fstack_line_reader.c;fp=src%2Ftype3_AndroidCloud%2Fanbox-master%2Fexternal%2Fcpu_features%2Fsrc%2Fstack_line_reader.c;h=b2c48ba6df30510ae39d505ab7c570fe6ff646af;hb=e26c1ec581be598521517829adba8c8dd23a768f;hp=0000000000000000000000000000000000000000;hpb=6699c1aea74eeb0eb400e6299079f0c7576f716f;p=iec.git diff --git a/src/type3_AndroidCloud/anbox-master/external/cpu_features/src/stack_line_reader.c b/src/type3_AndroidCloud/anbox-master/external/cpu_features/src/stack_line_reader.c new file mode 100644 index 0000000..b2c48ba --- /dev/null +++ b/src/type3_AndroidCloud/anbox-master/external/cpu_features/src/stack_line_reader.c @@ -0,0 +1,131 @@ +// Copyright 2017 Google Inc. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include "internal/stack_line_reader.h" +#include "internal/filesystem.h" + +#include +#include +#include + +void StackLineReader_Initialize(StackLineReader* reader, int fd) { + reader->view.ptr = reader->buffer; + reader->view.size = 0; + reader->skip_mode = false; + reader->fd = fd; +} + +// Replaces the content of buffer with bytes from the file. +static int LoadFullBuffer(StackLineReader* reader) { + const int read = CpuFeatures_ReadFile(reader->fd, reader->buffer, + STACK_LINE_READER_BUFFER_SIZE); + assert(read >= 0); + reader->view.ptr = reader->buffer; + reader->view.size = read; + return read; +} + +// Appends with bytes from the file to buffer, filling the remaining space. +static int LoadMore(StackLineReader* reader) { + char* const ptr = reader->buffer + reader->view.size; + const size_t size_to_read = STACK_LINE_READER_BUFFER_SIZE - reader->view.size; + const int read = CpuFeatures_ReadFile(reader->fd, ptr, size_to_read); + assert(read >= 0); + assert(read <= (int)size_to_read); + reader->view.size += read; + return read; +} + +static int IndexOfEol(StackLineReader* reader) { + return CpuFeatures_StringView_IndexOfChar(reader->view, '\n'); +} + +// Relocate buffer's pending bytes at the beginning of the array and fills the +// remaining space with bytes from the file. +static int BringToFrontAndLoadMore(StackLineReader* reader) { + if (reader->view.size && reader->view.ptr != reader->buffer) { + memmove(reader->buffer, reader->view.ptr, reader->view.size); + } + reader->view.ptr = reader->buffer; + return LoadMore(reader); +} + +// Loads chunks of buffer size from disks until it contains a newline character +// or end of file. +static void SkipToNextLine(StackLineReader* reader) { + for (;;) { + const int read = LoadFullBuffer(reader); + if (read == 0) { + break; + } else { + const int eol_index = IndexOfEol(reader); + if (eol_index >= 0) { + reader->view = + CpuFeatures_StringView_PopFront(reader->view, eol_index + 1); + break; + } + } + } +} + +static LineResult CreateLineResult(bool eof, bool full_line, StringView view) { + LineResult result; + result.eof = eof; + result.full_line = full_line; + result.line = view; + return result; +} + +// Helper methods to provide clearer semantic in StackLineReader_NextLine. +static LineResult CreateEOFLineResult(StringView view) { + return CreateLineResult(true, true, view); +} + +static LineResult CreateTruncatedLineResult(StringView view) { + return CreateLineResult(false, false, view); +} + +static LineResult CreateValidLineResult(StringView view) { + return CreateLineResult(false, true, view); +} + +LineResult StackLineReader_NextLine(StackLineReader* reader) { + if (reader->skip_mode) { + SkipToNextLine(reader); + reader->skip_mode = false; + } + { + const bool can_load_more = + reader->view.size < STACK_LINE_READER_BUFFER_SIZE; + int eol_index = IndexOfEol(reader); + if (eol_index < 0 && can_load_more) { + const int read = BringToFrontAndLoadMore(reader); + if (read == 0) { + return CreateEOFLineResult(reader->view); + } + eol_index = IndexOfEol(reader); + } + if (eol_index < 0) { + reader->skip_mode = true; + return CreateTruncatedLineResult(reader->view); + } + { + StringView line = + CpuFeatures_StringView_KeepFront(reader->view, eol_index); + reader->view = + CpuFeatures_StringView_PopFront(reader->view, eol_index + 1); + return CreateValidLineResult(line); + } + } +}