Added StringExtractor::DecodeHexU8 && GetHexBytesAvail
DecodeHexU8 returns a decoded hex character pair, returns -1 if a
valid hex pair is not available.
GetHexBytesAvail decodes all available hex pairs.
llvm-svn: 223081
diff --git a/lldb/source/Utility/StringExtractor.cpp b/lldb/source/Utility/StringExtractor.cpp
index 8747853..a2cbe6c 100644
--- a/lldb/source/Utility/StringExtractor.cpp
+++ b/lldb/source/Utility/StringExtractor.cpp
@@ -16,43 +16,6 @@
// Other libraries and framework includes
// Project includes
-static const uint8_t
-g_hex_ascii_to_hex_integer[256] = {
-
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,
- 0x8, 0x9, 255, 255, 255, 255, 255, 255,
- 255, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255,
-};
-
static inline int
xdigit_to_sint (char ch)
{
@@ -60,7 +23,9 @@
return 10 + ch - 'a';
if (ch >= 'A' && ch <= 'F')
return 10 + ch - 'A';
- return ch - '0';
+ if (ch >= '0' && ch <= '9')
+ return ch - '0';
+ return -1;
}
//----------------------------------------------------------------------
@@ -129,25 +94,45 @@
}
//----------------------------------------------------------------------
+// If a pair of valid hex digits exist at the head of the
+// StringExtractor they are decoded into an unsigned byte and returned
+// by this function
+//
+// If there is not a pair of valid hex digits at the head of the
+// StringExtractor, it is left unchanged and -1 is returned
+//----------------------------------------------------------------------
+int
+StringExtractor::DecodeHexU8()
+{
+ if (GetBytesLeft() < 2)
+ {
+ return -1;
+ }
+ const int hi_nibble = xdigit_to_sint(m_packet[m_index]);
+ const int lo_nibble = xdigit_to_sint(m_packet[m_index+1]);
+ if (hi_nibble == -1 || lo_nibble == -1)
+ {
+ return -1;
+ }
+ m_index += 2;
+ return (uint8_t)((hi_nibble << 4) + lo_nibble);
+}
+
+//----------------------------------------------------------------------
// Extract an unsigned character from two hex ASCII chars in the packet
// string
//----------------------------------------------------------------------
uint8_t
StringExtractor::GetHexU8 (uint8_t fail_value, bool set_eof_on_fail)
{
- if (GetBytesLeft() >= 2)
+ int byte = DecodeHexU8();
+ if (byte == -1)
{
- const uint8_t hi_nibble = g_hex_ascii_to_hex_integer[static_cast<uint8_t>(m_packet[m_index])];
- const uint8_t lo_nibble = g_hex_ascii_to_hex_integer[static_cast<uint8_t>(m_packet[m_index+1])];
- if (hi_nibble < 16 && lo_nibble < 16)
- {
- m_index += 2;
- return (hi_nibble << 4) + lo_nibble;
- }
+ if (set_eof_on_fail || m_index >= m_packet.size())
+ m_index = UINT64_MAX;
+ return fail_value;
}
- if (set_eof_on_fail || m_index >= m_packet.size())
- m_index = UINT64_MAX;
- return fail_value;
+ return (uint8_t)byte;
}
uint32_t
@@ -372,6 +357,28 @@
return bytes_extracted;
}
+//----------------------------------------------------------------------
+// Decodes all valid hex encoded bytes at the head of the
+// StringExtractor, limited by dst_len.
+//
+// Returns the number of bytes successfully decoded
+//----------------------------------------------------------------------
+size_t
+StringExtractor::GetHexBytesAvail (void *dst_void, size_t dst_len)
+{
+ uint8_t *dst = (uint8_t*)dst_void;
+ size_t bytes_extracted = 0;
+ while (bytes_extracted < dst_len)
+ {
+ int decode = DecodeHexU8();
+ if (decode == -1)
+ {
+ break;
+ }
+ dst[bytes_extracted++] = (uint8_t)decode;
+ }
+ return bytes_extracted;
+}
// Consume ASCII hex nibble character pairs until we have decoded byte_size
// bytes of data.
