[lldb] Remove usages of case-insensitive c-string functions

They are not portable (which meant we had a hand-rolled implementation
for windows), and llvm::StringRef provides equivalent functionality.

Author: labath

lldb/include/lldb/Host/windows/PosixApi.h

@@ -89,14 +89,6 @@ typedef uint32_t pid_t;
 // Various useful posix functions that are not present in Windows.  We provide
 // custom implementations.
 int vasprintf(char **ret, const char *fmt, va_list ap);
-char *strcasestr(const char *s, const char *find);
-
-#ifdef _MSC_VER
-
-int strcasecmp(const char *s1, const char *s2);
-int strncasecmp(const char *s1, const char *s2, size_t n);
-
-#endif // _MSC_VER
 
 // empty functions
 inline int posix_openpt(int flag) { LLVM_BUILTIN_UNREACHABLE; }

lldb/source/API/SBFrame.cpp

@@ -637,9 +637,9 @@ SBValue SBFrame::FindValue(const char *name, ValueType value_type,
             for (uint32_t set_idx = 0; set_idx < num_sets; ++set_idx) {
               const RegisterSet *reg_set = reg_ctx->GetRegisterSet(set_idx);
               if (reg_set &&
-                  ((reg_set->name && strcasecmp(reg_set->name, name) == 0) ||
-                   (reg_set->short_name &&
-                    strcasecmp(reg_set->short_name, name) == 0))) {
+                  (llvm::StringRef(reg_set->name).equals_insensitive(name) ||
+                   llvm::StringRef(reg_set->short_name)
+                       .equals_insensitive(name))) {
                 value_sp =
                     ValueObjectRegisterSet::Create(frame, reg_ctx, set_idx);
                 sb_value.SetSP(value_sp);

lldb/source/DataFormatters/FormatManager.cpp

@@ -89,20 +89,20 @@ static bool GetFormatFromFormatChar(char format_char, Format &format) {
   return false;
 }
 
-static bool GetFormatFromFormatName(const char *format_name,
+static bool GetFormatFromFormatName(llvm::StringRef format_name,
                                     bool partial_match_ok, Format &format) {
   uint32_t i;
   for (i = 0; i < g_num_format_infos; ++i) {
-    if (strcasecmp(g_format_infos[i].format_name, format_name) == 0) {
+    if (format_name.equals_insensitive(g_format_infos[i].format_name)) {
       format = g_format_infos[i].format;
       return true;
     }
   }
 
   if (partial_match_ok) {
     for (i = 0; i < g_num_format_infos; ++i) {
-      if (strcasestr(g_format_infos[i].format_name, format_name) ==
-          g_format_infos[i].format_name) {
+      if (llvm::StringRef(g_format_infos[i].format_name)
+              .startswith_insensitive(format_name)) {
         format = g_format_infos[i].format;
         return true;
       }

lldb/source/Host/windows/Windows.cpp

@@ -44,32 +44,8 @@ int vasprintf(char **ret, const char *fmt, va_list ap) {
   return len;
 }
 
-char *strcasestr(const char *s, const char *find) {
-  char c, sc;
-  size_t len;
-
-  if ((c = *find++) != 0) {
-    c = tolower((unsigned char)c);
-    len = strlen(find);
-    do {
-      do {
-        if ((sc = *s++) == 0)
-          return 0;
-      } while ((char)tolower((unsigned char)sc) != c);
-    } while (strncasecmp(s, find, len) != 0);
-    s--;
-  }
-  return const_cast<char *>(s);
-}
-
 #ifdef _MSC_VER
 
-int strcasecmp(const char *s1, const char *s2) { return stricmp(s1, s2); }
-
-int strncasecmp(const char *s1, const char *s2, size_t n) {
-  return strnicmp(s1, s2, n);
-}
-
 #if _MSC_VER < 1900
 namespace lldb_private {
 int vsnprintf(char *buffer, size_t count, const char *format, va_list argptr) {

lldb/source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp

@@ -13761,35 +13761,33 @@ EmulateInstructionARM::GetThumbOpcodeForInstruction(const uint32_t opcode,
 bool EmulateInstructionARM::SetArchitecture(const ArchSpec &arch) {
   m_arch = arch;
   m_arm_isa = 0;
-  const char *arch_cstr = arch.GetArchitectureName();
-  if (arch_cstr) {
-    if (0 == ::strcasecmp(arch_cstr, "armv4t"))
-      m_arm_isa = ARMv4T;
-    else if (0 == ::strcasecmp(arch_cstr, "armv5tej"))
-      m_arm_isa = ARMv5TEJ;
-    else if (0 == ::strcasecmp(arch_cstr, "armv5te"))
-      m_arm_isa = ARMv5TE;
-    else if (0 == ::strcasecmp(arch_cstr, "armv5t"))
-      m_arm_isa = ARMv5T;
-    else if (0 == ::strcasecmp(arch_cstr, "armv6k"))
-      m_arm_isa = ARMv6K;
-    else if (0 == ::strcasecmp(arch_cstr, "armv6t2"))
-      m_arm_isa = ARMv6T2;
-    else if (0 == ::strcasecmp(arch_cstr, "armv7s"))
-      m_arm_isa = ARMv7S;
-    else if (0 == ::strcasecmp(arch_cstr, "arm"))
-      m_arm_isa = ARMvAll;
-    else if (0 == ::strcasecmp(arch_cstr, "thumb"))
-      m_arm_isa = ARMvAll;
-    else if (0 == ::strncasecmp(arch_cstr, "armv4", 5))
-      m_arm_isa = ARMv4;
-    else if (0 == ::strncasecmp(arch_cstr, "armv6", 5))
-      m_arm_isa = ARMv6;
-    else if (0 == ::strncasecmp(arch_cstr, "armv7", 5))
-      m_arm_isa = ARMv7;
-    else if (0 == ::strncasecmp(arch_cstr, "armv8", 5))
-      m_arm_isa = ARMv8;
-  }
+  llvm::StringRef arch_cstr = arch.GetArchitectureName();
+  if (arch_cstr.equals_insensitive("armv4t"))
+    m_arm_isa = ARMv4T;
+  else if (arch_cstr.equals_insensitive("armv5tej"))
+    m_arm_isa = ARMv5TEJ;
+  else if (arch_cstr.equals_insensitive("armv5te"))
+    m_arm_isa = ARMv5TE;
+  else if (arch_cstr.equals_insensitive("armv5t"))
+    m_arm_isa = ARMv5T;
+  else if (arch_cstr.equals_insensitive("armv6k"))
+    m_arm_isa = ARMv6K;
+  else if (arch_cstr.equals_insensitive("armv6t2"))
+    m_arm_isa = ARMv6T2;
+  else if (arch_cstr.equals_insensitive("armv7s"))
+    m_arm_isa = ARMv7S;
+  else if (arch_cstr.equals_insensitive("arm"))
+    m_arm_isa = ARMvAll;
+  else if (arch_cstr.equals_insensitive("thumb"))
+    m_arm_isa = ARMvAll;
+  else if (arch_cstr.startswith_insensitive("armv4"))
+    m_arm_isa = ARMv4;
+  else if (arch_cstr.startswith_insensitive("armv6"))
+    m_arm_isa = ARMv6;
+  else if (arch_cstr.startswith_insensitive("armv7"))
+    m_arm_isa = ARMv7;
+  else if (arch_cstr.startswith_insensitive("armv8"))
+    m_arm_isa = ARMv8;
   return m_arm_isa != 0;
 }