Use Byte/WideString iterators

Change-Id: I85c8423c177fd7ecd5da90ef89419efc0f9cf44b
Reviewed-on: https://pdfium-review.googlesource.com/4262
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

8 files changed, 20 insertions, 46 deletions

diff --git a/fxbarcode/BC_UtilCodingConvert.cpp b/fxbarcode/BC_UtilCodingConvert.cpp
index f1dea885c3..f0f497a07b 100644
--- a/fxbarcode/BC_UtilCodingConvert.cpp
+++ b/fxbarcode/BC_UtilCodingConvert.cpp
@@ -25,9 +25,7 @@ void CBC_UtilCodingConvert::LocaleToUtf8(const CFX_ByteString& src,
                                          std::vector<uint8_t>& dst) {
   CFX_WideString unicode = CFX_WideString::FromLocal(src.AsStringC());
   CFX_ByteString utf8 = unicode.UTF8Encode();
-  for (int32_t i = 0; i < utf8.GetLength(); i++) {
-    dst.push_back(utf8[i]);
-  }
+  dst = std::vector<uint8_t>(utf8.begin(), utf8.end());
 }
 
 void CBC_UtilCodingConvert::Utf8ToLocale(const std::vector<uint8_t>& src,
diff --git a/fxbarcode/datamatrix/BC_Base256Encoder.cpp b/fxbarcode/datamatrix/BC_Base256Encoder.cpp
index 1b8db85bdd..dd49c8e0f5 100644
--- a/fxbarcode/datamatrix/BC_Base256Encoder.cpp
+++ b/fxbarcode/datamatrix/BC_Base256Encoder.cpp
@@ -70,9 +70,8 @@ void CBC_Base256Encoder::Encode(CBC_EncoderContext& context, int32_t& e) {
       return;
     }
   }
-  for (int32_t i = 0, c = buffer.GetLength(); i < c; i++) {
-    context.writeCodeword(
-        randomize255State(buffer.GetAt(i), context.getCodewordCount() + 1));
+  for (const auto& c : buffer) {
+    context.writeCodeword(randomize255State(c, context.getCodewordCount() + 1));
   }
 }
 wchar_t CBC_Base256Encoder::randomize255State(wchar_t ch,
diff --git a/fxbarcode/datamatrix/BC_HighLevelEncoder.cpp b/fxbarcode/datamatrix/BC_HighLevelEncoder.cpp
index 041272ef8c..cce9749749 100644
--- a/fxbarcode/datamatrix/BC_HighLevelEncoder.cpp
+++ b/fxbarcode/datamatrix/BC_HighLevelEncoder.cpp
@@ -63,8 +63,7 @@ std::vector<uint8_t>& CBC_HighLevelEncoder::getBytesForMessage(
     CFX_WideString msg) {
   CFX_ByteString bytestr;
   CBC_UtilCodingConvert::UnicodeToUTF8(msg, bytestr);
-  for (int32_t i = 0; i < bytestr.GetLength(); i++)
-    m_bytearray.push_back(bytestr.GetAt(i));
+  m_bytearray.insert(m_bytearray.end(), bytestr.begin(), bytestr.end());
   return m_bytearray;
 }
 CFX_WideString CBC_HighLevelEncoder::encodeHighLevel(CFX_WideString msg,
diff --git a/fxbarcode/oned/BC_OnedCodaBarWriter.cpp b/fxbarcode/oned/BC_OnedCodaBarWriter.cpp
index 6c04cafe7b..d3706ab96d 100644
--- a/fxbarcode/oned/BC_OnedCodaBarWriter.cpp
+++ b/fxbarcode/oned/BC_OnedCodaBarWriter.cpp
@@ -108,18 +108,11 @@ bool CBC_OnedCodaBarWriter::FindChar(wchar_t ch, bool isContent) {
 }
 bool CBC_OnedCodaBarWriter::CheckContentValidity(
     const CFX_WideStringC& contents) {
-  wchar_t ch;
-  int32_t index = 0;
-  for (index = 0; index < contents.GetLength(); index++) {
-    ch = contents.GetAt(index);
-    if (FindChar(ch, false)) {
-      continue;
-    } else {
-      return false;
-    }
-  }
-  return true;
+  return std::all_of(
+      contents.begin(), contents.end(),
+      [this](const wchar_t& ch) { return this->FindChar(ch, false); });
 }
+
 CFX_WideString CBC_OnedCodaBarWriter::FilterContents(
     const CFX_WideStringC& contents) {
   CFX_WideString filtercontents;
diff --git a/fxbarcode/oned/BC_OnedCode128Writer.cpp b/fxbarcode/oned/BC_OnedCode128Writer.cpp
index 53f4d01449..e2b6823414 100644
--- a/fxbarcode/oned/BC_OnedCode128Writer.cpp
+++ b/fxbarcode/oned/BC_OnedCode128Writer.cpp
@@ -113,22 +113,14 @@ CFX_WideString CBC_OnedCode128Writer::FilterContents(
   }
   CFX_WideString filtercontents;
   if (m_codeFormat == BC_CODE128_B) {
-    for (int32_t i = 0; i < filterChineseChar.GetLength(); i++) {
-      ch = filterChineseChar.GetAt(i);
-      if (ch >= 32 && ch <= 126) {
+    for (const auto& ch : filterChineseChar) {
+      if (ch >= 32 && ch <= 126)
         filtercontents += ch;
-      } else {
-        continue;
-      }
     }
   } else if (m_codeFormat == BC_CODE128_C) {
-    for (int32_t i = 0; i < filterChineseChar.GetLength(); i++) {
-      ch = filterChineseChar.GetAt(i);
-      if (ch >= 32 && ch <= 106) {
+    for (const auto& ch : filterChineseChar) {
+      if (ch >= 32 && ch <= 106)
         filtercontents += ch;
-      } else {
-        continue;
-      }
     }
   } else {
     filtercontents = contents;
diff --git a/fxbarcode/oned/BC_OnedCode39Writer.cpp b/fxbarcode/oned/BC_OnedCode39Writer.cpp
index bcc64d83bd..b1a56cad40 100644
--- a/fxbarcode/oned/BC_OnedCode39Writer.cpp
+++ b/fxbarcode/oned/BC_OnedCode39Writer.cpp
@@ -163,11 +163,11 @@ char CBC_OnedCode39Writer::CalcCheckSum(const CFX_ByteString& contents,
   }
   int32_t checksum = 0;
   int32_t len = (int32_t)strlen(ALPHABET_STRING);
-  for (int32_t i = 0; i < contents.GetLength(); i++) {
+  for (const auto& c : contents) {
     int32_t j = 0;
     for (; j < len; j++) {
-      if (ALPHABET_STRING[j] == contents[i]) {
-        if (contents[i] != '*')
+      if (ALPHABET_STRING[j] == c) {
+        if (c != '*')
           checksum += j;
         break;
       }
diff --git a/fxbarcode/oned/BC_OnedEAN13Writer.cpp b/fxbarcode/oned/BC_OnedEAN13Writer.cpp
index a11938a4d9..96b51b0570 100644
--- a/fxbarcode/oned/BC_OnedEAN13Writer.cpp
+++ b/fxbarcode/oned/BC_OnedEAN13Writer.cpp
@@ -48,17 +48,13 @@ CBC_OnedEAN13Writer::CBC_OnedEAN13Writer() {
   m_codeWidth = 3 + (7 * 6) + 5 + (7 * 6) + 3;
 }
 CBC_OnedEAN13Writer::~CBC_OnedEAN13Writer() {}
+
 bool CBC_OnedEAN13Writer::CheckContentValidity(
     const CFX_WideStringC& contents) {
-  for (int32_t i = 0; i < contents.GetLength(); i++) {
-    if (contents.GetAt(i) >= '0' && contents.GetAt(i) <= '9') {
-      continue;
-    } else {
-      return false;
-    }
-  }
-  return true;
+  return std::all_of(contents.begin(), contents.end(),
+                     [](const wchar_t& w) { return w >= L'0' && w <= L'9'; });
 }
+
 CFX_WideString CBC_OnedEAN13Writer::FilterContents(
     const CFX_WideStringC& contents) {
   CFX_WideString filtercontents;
diff --git a/fxbarcode/pdf417/BC_PDF417HighLevelEncoder.cpp b/fxbarcode/pdf417/BC_PDF417HighLevelEncoder.cpp
index ac8b0186f6..f65cfe46ae 100644
--- a/fxbarcode/pdf417/BC_PDF417HighLevelEncoder.cpp
+++ b/fxbarcode/pdf417/BC_PDF417HighLevelEncoder.cpp
@@ -71,10 +71,7 @@ CFX_WideString CBC_PDF417HighLevelEncoder::encodeHighLevel(
     }
     msg += ch;
   }
-  std::vector<uint8_t> byteArr;
-  for (int32_t k = 0; k < bytes.GetLength(); k++) {
-    byteArr.push_back(bytes.GetAt(k));
-  }
+  std::vector<uint8_t> byteArr(bytes.begin(), bytes.end());
   CFX_WideString sb;
   len = msg.GetLength();
   int32_t p = 0;