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-rw-r--r--intl/icu/source/common/stringpiece.cpp116
1 files changed, 116 insertions, 0 deletions
diff --git a/intl/icu/source/common/stringpiece.cpp b/intl/icu/source/common/stringpiece.cpp
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index 0000000000..eb9766c018
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+++ b/intl/icu/source/common/stringpiece.cpp
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+// © 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+// Copyright (C) 2009-2013, International Business Machines
+// Corporation and others. All Rights Reserved.
+//
+// Copyright 2004 and onwards Google Inc.
+//
+// Author: wilsonh@google.com (Wilson Hsieh)
+//
+
+#include "unicode/utypes.h"
+#include "unicode/stringpiece.h"
+#include "cstring.h"
+#include "cmemory.h"
+
+U_NAMESPACE_BEGIN
+
+StringPiece::StringPiece(const char* str)
+ : ptr_(str), length_((str == nullptr) ? 0 : static_cast<int32_t>(uprv_strlen(str))) { }
+
+StringPiece::StringPiece(const StringPiece& x, int32_t pos) {
+ if (pos < 0) {
+ pos = 0;
+ } else if (pos > x.length_) {
+ pos = x.length_;
+ }
+ ptr_ = x.ptr_ + pos;
+ length_ = x.length_ - pos;
+}
+
+StringPiece::StringPiece(const StringPiece& x, int32_t pos, int32_t len) {
+ if (pos < 0) {
+ pos = 0;
+ } else if (pos > x.length_) {
+ pos = x.length_;
+ }
+ if (len < 0) {
+ len = 0;
+ } else if (len > x.length_ - pos) {
+ len = x.length_ - pos;
+ }
+ ptr_ = x.ptr_ + pos;
+ length_ = len;
+}
+
+void StringPiece::set(const char* str) {
+ ptr_ = str;
+ if (str != nullptr)
+ length_ = static_cast<int32_t>(uprv_strlen(str));
+ else
+ length_ = 0;
+}
+
+int32_t StringPiece::find(StringPiece needle, int32_t offset) {
+ if (length() == 0 && needle.length() == 0) {
+ return 0;
+ }
+ // TODO: Improve to be better than O(N^2)?
+ for (int32_t i = offset; i < length(); i++) {
+ int32_t j = 0;
+ for (; j < needle.length(); i++, j++) {
+ if (data()[i] != needle.data()[j]) {
+ i -= j;
+ goto outer_end;
+ }
+ }
+ return i - j;
+ outer_end: void();
+ }
+ return -1;
+}
+
+int32_t StringPiece::compare(StringPiece other) {
+ int32_t i = 0;
+ for (; i < length(); i++) {
+ if (i == other.length()) {
+ // this is longer
+ return 1;
+ }
+ char a = data()[i];
+ char b = other.data()[i];
+ if (a < b) {
+ return -1;
+ } else if (a > b) {
+ return 1;
+ }
+ }
+ if (i < other.length()) {
+ // other is longer
+ return -1;
+ }
+ return 0;
+}
+
+U_EXPORT UBool U_EXPORT2
+operator==(const StringPiece& x, const StringPiece& y) {
+ int32_t len = x.size();
+ if (len != y.size()) {
+ return false;
+ }
+ if (len == 0) {
+ return true;
+ }
+ const char* p = x.data();
+ const char* p2 = y.data();
+ // Test last byte in case strings share large common prefix
+ --len;
+ if (p[len] != p2[len]) return false;
+ // At this point we can, but don't have to, ignore the last byte.
+ return uprv_memcmp(p, p2, len) == 0;
+}
+
+
+const int32_t StringPiece::npos = 0x7fffffff;
+
+U_NAMESPACE_END