Add much-needed Find() method for CFX_*StringC

BUG=pdfium:493

Review-Url: https://codereview.chromium.org/1968233002

7 files changed, 75 insertions, 20 deletions

diff --git a/core/fxcrt/fx_basic_bstring.cpp b/core/fxcrt/fx_basic_bstring.cpp
index cd7b616fbe..18e240bc84 100644
--- a/core/fxcrt/fx_basic_bstring.cpp
+++ b/core/fxcrt/fx_basic_bstring.cpp
@@ -673,11 +673,12 @@ FX_STRSIZE CFX_ByteString::Find(FX_CHAR ch, FX_STRSIZE nStart) const {
   if (!m_pData)
     return -1;
 
-  if (nStart >= m_pData->m_nDataLength)
+  if (nStart < 0 || nStart >= m_pData->m_nDataLength)
     return -1;
 
-  const FX_CHAR* pStr = FXSYS_strchr(m_pData->m_String + nStart, ch);
-  return pStr ? (int)(pStr - m_pData->m_String) : -1;
+  const FX_CHAR* pStr = static_cast<const FX_CHAR*>(
+      memchr(m_pData->m_String + nStart, ch, m_pData->m_nDataLength - nStart));
+  return pStr ? pStr - m_pData->m_String : -1;
 }
 
 FX_STRSIZE CFX_ByteString::ReverseFind(FX_CHAR ch) const {
diff --git a/core/fxcrt/fx_basic_bstring_unittest.cpp b/core/fxcrt/fx_basic_bstring_unittest.cpp
index 087c264940..fe98b53b45 100644
--- a/core/fxcrt/fx_basic_bstring_unittest.cpp
+++ b/core/fxcrt/fx_basic_bstring_unittest.cpp
@@ -802,6 +802,31 @@ TEST(fxcrt, ByteStringCGetID) {
   EXPECT_EQ(0u, longer_string.GetID(-1000000));
 }
 
+TEST(fxcrt, ByteStringCFind) {
+  CFX_ByteStringC null_string;
+  EXPECT_EQ(-1, null_string.Find('a'));
+  EXPECT_EQ(-1, null_string.Find(0));
+
+  CFX_ByteStringC empty_string("");
+  EXPECT_EQ(-1, empty_string.Find('a'));
+  EXPECT_EQ(-1, empty_string.Find(0));
+
+  CFX_ByteStringC single_string("a");
+  EXPECT_EQ(0, single_string.Find('a'));
+  EXPECT_EQ(-1, single_string.Find('b'));
+  EXPECT_EQ(-1, single_string.Find(0));
+
+  CFX_ByteStringC longer_string("abccc");
+  EXPECT_EQ(0, longer_string.Find('a'));
+  EXPECT_EQ(2, longer_string.Find('c'));
+  EXPECT_EQ(-1, longer_string.Find(0));
+
+  CFX_ByteStringC hibyte_string(
+      "ab\x8c"
+      "def");
+  EXPECT_EQ(2, hibyte_string.Find('\x8c'));
+}
+
 TEST(fxcrt, ByteStringCMid) {
   CFX_ByteStringC null_string;
   EXPECT_EQ(null_string, null_string.Mid(0, 1));
diff --git a/core/fxcrt/fx_basic_util.cpp b/core/fxcrt/fx_basic_util.cpp
index 1cf966589d..f69185653f 100644
--- a/core/fxcrt/fx_basic_util.cpp
+++ b/core/fxcrt/fx_basic_util.cpp
@@ -95,7 +95,7 @@ void CFX_PrivateData::ClearAll() {
   m_DataList.RemoveAll();
 }
 void FX_atonum(const CFX_ByteStringC& strc, FX_BOOL& bInteger, void* pData) {
-  if (!FXSYS_memchr(strc.raw_str(), '.', strc.GetLength())) {
+  if (strc.Find('.') == -1) {
     bInteger = TRUE;
     int cc = 0, integer = 0;
     const FX_CHAR* str = strc.c_str();
diff --git a/core/fxcrt/fx_basic_wstring.cpp b/core/fxcrt/fx_basic_wstring.cpp
index 354bb5014a..03cb0599d5 100644
--- a/core/fxcrt/fx_basic_wstring.cpp
+++ b/core/fxcrt/fx_basic_wstring.cpp
@@ -638,11 +638,12 @@ FX_STRSIZE CFX_WideString::Find(FX_WCHAR ch, FX_STRSIZE nStart) const {
   if (!m_pData)
     return -1;
 
-  if (nStart >= m_pData->m_nDataLength)
+  if (nStart < 0 || nStart >= m_pData->m_nDataLength)
     return -1;
 
-  const FX_WCHAR* pStr = FXSYS_wcschr(m_pData->m_String + nStart, ch);
-  return pStr ? (int)(pStr - m_pData->m_String) : -1;
+  const FX_WCHAR* pStr =
+      wmemchr(m_pData->m_String + nStart, ch, m_pData->m_nDataLength - nStart);
+  return pStr ? pStr - m_pData->m_String : -1;
 }
 
 FX_STRSIZE CFX_WideString::Find(const CFX_WideStringC& pSub,
@@ -858,19 +859,13 @@ FX_STRSIZE CFX_WideString::WStringLength(const unsigned short* str) {
 }
 
 void CFX_WideString::TrimRight(const CFX_WideStringC& pTargets) {
-  if (!m_pData || pTargets.IsEmpty()) {
+  if (IsEmpty() || pTargets.IsEmpty())
     return;
-  }
+
   FX_STRSIZE pos = GetLength();
-  if (pos < 1) {
-    return;
-  }
-  while (pos) {
-    if (!FXSYS_wcschr(pTargets.c_str(), m_pData->m_String[pos - 1])) {
-      break;
-    }
+  while (pos && pTargets.Find(m_pData->m_String[pos - 1]) != -1)
     pos--;
-  }
+
   if (pos < m_pData->m_nDataLength) {
     ReallocBeforeWrite(m_pData->m_nDataLength);
     m_pData->m_String[pos] = 0;
diff --git a/core/fxcrt/fx_basic_wstring_unittest.cpp b/core/fxcrt/fx_basic_wstring_unittest.cpp
index 02281afd36..4b6f4a5800 100644
--- a/core/fxcrt/fx_basic_wstring_unittest.cpp
+++ b/core/fxcrt/fx_basic_wstring_unittest.cpp
@@ -831,6 +831,31 @@ TEST(fxcrt, WideStringCOperatorNE) {
   EXPECT_TRUE(c_string3 != wide_string_c);
 }
 
+TEST(fxcrt, WideStringCFind) {
+  CFX_WideStringC null_string;
+  EXPECT_EQ(-1, null_string.Find(L'a'));
+  EXPECT_EQ(-1, null_string.Find(0));
+
+  CFX_WideStringC empty_string(L"");
+  EXPECT_EQ(-1, empty_string.Find(L'a'));
+  EXPECT_EQ(-1, empty_string.Find(0));
+
+  CFX_WideStringC single_string(L"a");
+  EXPECT_EQ(0, single_string.Find(L'a'));
+  EXPECT_EQ(-1, single_string.Find(L'b'));
+  EXPECT_EQ(-1, single_string.Find(0));
+
+  CFX_WideStringC longer_string(L"abccc");
+  EXPECT_EQ(0, longer_string.Find(L'a'));
+  EXPECT_EQ(2, longer_string.Find(L'c'));
+  EXPECT_EQ(-1, longer_string.Find(0));
+
+  CFX_WideStringC hibyte_string(
+      L"ab\xff08"
+      L"def");
+  EXPECT_EQ(2, hibyte_string.Find(L'\xff08'));
+}
+
 TEST(fxcrt, WideStringFormatWidth) {
   {
     CFX_WideString str;
diff --git a/core/fxcrt/include/fx_string.h b/core/fxcrt/include/fx_string.h
index 66a8039a8d..fbfb91f759 100644
--- a/core/fxcrt/include/fx_string.h
+++ b/core/fxcrt/include/fx_string.h
@@ -100,6 +100,12 @@ class CFX_ByteStringC {
 
   uint8_t GetAt(FX_STRSIZE index) const { return m_Ptr[index]; }
 
+  FX_STRSIZE Find(FX_CHAR ch) const {
+    const uint8_t* found =
+        static_cast<const uint8_t*>(memchr(m_Ptr, ch, m_Length));
+    return found ? found - m_Ptr : -1;
+  }
+
   CFX_ByteStringC Mid(FX_STRSIZE index, FX_STRSIZE count = -1) const {
     if (index < 0) {
       index = 0;
@@ -417,6 +423,12 @@ class CFX_WideStringC {
     return CFX_WideStringC(m_Ptr, count);
   }
 
+  FX_STRSIZE Find(FX_WCHAR ch) const {
+    const FX_WCHAR* found =
+        static_cast<const FX_WCHAR*>(wmemchr(m_Ptr, ch, m_Length));
+    return found ? found - m_Ptr : -1;
+  }
+
   CFX_WideStringC Mid(FX_STRSIZE index, FX_STRSIZE count = -1) const {
     if (index < 0) {
       index = 0;
diff --git a/core/fxcrt/include/fx_system.h b/core/fxcrt/include/fx_system.h
index 795a0c2794..b4659d14e4 100644
--- a/core/fxcrt/include/fx_system.h
+++ b/core/fxcrt/include/fx_system.h
@@ -123,7 +123,6 @@ void FXSYS_vsnprintf(char* str, size_t size, const char* fmt, va_list ap);
 
 #define FXSYS_sprintf DO_NOT_USE_SPRINTF_DIE_DIE_DIE
 #define FXSYS_vsprintf DO_NOT_USE_VSPRINTF_DIE_DIE_DIE
-#define FXSYS_strchr strchr
 #define FXSYS_strncmp strncmp
 #define FXSYS_strcmp strcmp
 #define FXSYS_strcpy strcpy
@@ -166,7 +165,6 @@ extern "C" {
 #endif
 
 #define FXSYS_wcscmp wcscmp
-#define FXSYS_wcschr wcschr
 #define FXSYS_wcsstr wcsstr
 #define FXSYS_wcsncmp wcsncmp
 #define FXSYS_vswprintf vswprintf
@@ -176,7 +174,6 @@ extern "C" {
 #define FXSYS_memcpy memcpy
 #define FXSYS_memmove memmove
 #define FXSYS_memset memset
-#define FXSYS_memchr memchr
 #define FXSYS_qsort qsort
 #define FXSYS_bsearch bsearch