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authorAnton Samokhvalov <pg83@yandex.ru>2022-02-10 16:45:15 +0300
committerDaniil Cherednik <dcherednik@yandex-team.ru>2022-02-10 16:45:15 +0300
commit72cb13b4aff9bc9cf22e49251bc8fd143f82538f (patch)
treeda2c34829458c7d4e74bdfbdf85dff449e9e7fb8 /contrib/libs/snappy/snappy-stubs-internal.h
parent778e51ba091dc39e7b7fcab2b9cf4dbedfb6f2b5 (diff)
downloadydb-72cb13b4aff9bc9cf22e49251bc8fd143f82538f.tar.gz
Restoring authorship annotation for Anton Samokhvalov <pg83@yandex.ru>. Commit 1 of 2.
Diffstat (limited to 'contrib/libs/snappy/snappy-stubs-internal.h')
-rw-r--r--contrib/libs/snappy/snappy-stubs-internal.h720
1 files changed, 360 insertions, 360 deletions
diff --git a/contrib/libs/snappy/snappy-stubs-internal.h b/contrib/libs/snappy/snappy-stubs-internal.h
index 4854689d17..48b40bac98 100644
--- a/contrib/libs/snappy/snappy-stubs-internal.h
+++ b/contrib/libs/snappy/snappy-stubs-internal.h
@@ -1,46 +1,46 @@
-// Copyright 2011 Google Inc. All Rights Reserved.
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-// * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-// * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-// * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-//
-// Various stubs for the open-source version of Snappy.
-
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Various stubs for the open-source version of Snappy.
+
#ifndef THIRD_PARTY_SNAPPY_OPENSOURCE_SNAPPY_STUBS_INTERNAL_H_
#define THIRD_PARTY_SNAPPY_OPENSOURCE_SNAPPY_STUBS_INTERNAL_H_
-
+
#ifdef HAVE_CONFIG_H
#include "config.h"
-#endif
-
+#endif
+
#include <string>
-
-#include <assert.h>
-#include <stdlib.h>
-#include <string.h>
-
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif
@@ -65,13 +65,13 @@
#define SNAPPY_ANNOTATE_MEMORY_IS_INITIALIZED(address, size) /* empty */
#endif // __has_feature(memory_sanitizer)
-#include "snappy-stubs-public.h"
-
-#if defined(__x86_64__)
-
-// Enable 64-bit optimized versions of some routines.
-#define ARCH_K8 1
-
+#include "snappy-stubs-public.h"
+
+#if defined(__x86_64__)
+
+// Enable 64-bit optimized versions of some routines.
+#define ARCH_K8 1
+
#elif defined(__ppc64__)
#define ARCH_PPC 1
@@ -80,21 +80,21 @@
#define ARCH_ARM 1
-#endif
-
-// Needed by OS X, among others.
-#ifndef MAP_ANONYMOUS
-#define MAP_ANONYMOUS MAP_ANON
-#endif
-
-// The size of an array, if known at compile-time.
-// Will give unexpected results if used on a pointer.
-// We undefine it first, since some compilers already have a definition.
-#ifdef ARRAYSIZE
-#undef ARRAYSIZE
-#endif
-#define ARRAYSIZE(a) (sizeof(a) / sizeof(*(a)))
-
+#endif
+
+// Needed by OS X, among others.
+#ifndef MAP_ANONYMOUS
+#define MAP_ANONYMOUS MAP_ANON
+#endif
+
+// The size of an array, if known at compile-time.
+// Will give unexpected results if used on a pointer.
+// We undefine it first, since some compilers already have a definition.
+#ifdef ARRAYSIZE
+#undef ARRAYSIZE
+#endif
+#define ARRAYSIZE(a) (sizeof(a) / sizeof(*(a)))
+
// Static prediction hints.
#ifdef HAVE_BUILTIN_EXPECT
#define SNAPPY_PREDICT_FALSE(x) (__builtin_expect(x, 0))
@@ -103,44 +103,44 @@
#define SNAPPY_PREDICT_FALSE(x) x
#define SNAPPY_PREDICT_TRUE(x) x
#endif
-
-// This is only used for recomputing the tag byte table used during
-// decompression; for simplicity we just remove it from the open-source
-// version (anyone who wants to regenerate it can just do the call
-// themselves within main()).
-#define DEFINE_bool(flag_name, default_value, description) \
- bool FLAGS_ ## flag_name = default_value
-#define DECLARE_bool(flag_name) \
- extern bool FLAGS_ ## flag_name
-
-namespace snappy {
-
-static const uint32 kuint32max = static_cast<uint32>(0xFFFFFFFF);
-static const int64 kint64max = static_cast<int64>(0x7FFFFFFFFFFFFFFFLL);
-
-// Potentially unaligned loads and stores.
-
+
+// This is only used for recomputing the tag byte table used during
+// decompression; for simplicity we just remove it from the open-source
+// version (anyone who wants to regenerate it can just do the call
+// themselves within main()).
+#define DEFINE_bool(flag_name, default_value, description) \
+ bool FLAGS_ ## flag_name = default_value
+#define DECLARE_bool(flag_name) \
+ extern bool FLAGS_ ## flag_name
+
+namespace snappy {
+
+static const uint32 kuint32max = static_cast<uint32>(0xFFFFFFFF);
+static const int64 kint64max = static_cast<int64>(0x7FFFFFFFFFFFFFFFLL);
+
+// Potentially unaligned loads and stores.
+
// x86, PowerPC, and ARM64 can simply do these loads and stores native.
-
+
#if defined(__i386__) || defined(__x86_64__) || defined(__powerpc__) || \
defined(__aarch64__)
-
-#define UNALIGNED_LOAD16(_p) (*reinterpret_cast<const uint16 *>(_p))
-#define UNALIGNED_LOAD32(_p) (*reinterpret_cast<const uint32 *>(_p))
-#define UNALIGNED_LOAD64(_p) (*reinterpret_cast<const uint64 *>(_p))
-
-#define UNALIGNED_STORE16(_p, _val) (*reinterpret_cast<uint16 *>(_p) = (_val))
-#define UNALIGNED_STORE32(_p, _val) (*reinterpret_cast<uint32 *>(_p) = (_val))
-#define UNALIGNED_STORE64(_p, _val) (*reinterpret_cast<uint64 *>(_p) = (_val))
-
-// ARMv7 and newer support native unaligned accesses, but only of 16-bit
-// and 32-bit values (not 64-bit); older versions either raise a fatal signal,
-// do an unaligned read and rotate the words around a bit, or do the reads very
-// slowly (trip through kernel mode). There's no simple #define that says just
-// “ARMv7 or higher”, so we have to filter away all ARMv5 and ARMv6
-// sub-architectures.
-//
-// This is a mess, but there's not much we can do about it.
+
+#define UNALIGNED_LOAD16(_p) (*reinterpret_cast<const uint16 *>(_p))
+#define UNALIGNED_LOAD32(_p) (*reinterpret_cast<const uint32 *>(_p))
+#define UNALIGNED_LOAD64(_p) (*reinterpret_cast<const uint64 *>(_p))
+
+#define UNALIGNED_STORE16(_p, _val) (*reinterpret_cast<uint16 *>(_p) = (_val))
+#define UNALIGNED_STORE32(_p, _val) (*reinterpret_cast<uint32 *>(_p) = (_val))
+#define UNALIGNED_STORE64(_p, _val) (*reinterpret_cast<uint64 *>(_p) = (_val))
+
+// ARMv7 and newer support native unaligned accesses, but only of 16-bit
+// and 32-bit values (not 64-bit); older versions either raise a fatal signal,
+// do an unaligned read and rotate the words around a bit, or do the reads very
+// slowly (trip through kernel mode). There's no simple #define that says just
+// “ARMv7 or higher”, so we have to filter away all ARMv5 and ARMv6
+// sub-architectures.
+//
+// This is a mess, but there's not much we can do about it.
//
// To further complicate matters, only LDR instructions (single reads) are
// allowed to be unaligned, not LDRD (two reads) or LDM (many reads). Unless we
@@ -150,30 +150,30 @@ static const int64 kint64max = static_cast<int64>(0x7FFFFFFFFFFFFFFFLL);
// (it ignores __attribute__((packed)) on individual variables). However,
// we can tell it that a _struct_ is unaligned, which has the same effect,
// so we do that.
-
-#elif defined(__arm__) && \
+
+#elif defined(__arm__) && \
!defined(__ARM_ARCH_4__) && \
!defined(__ARM_ARCH_4T__) && \
- !defined(__ARM_ARCH_5__) && \
- !defined(__ARM_ARCH_5T__) && \
- !defined(__ARM_ARCH_5TE__) && \
- !defined(__ARM_ARCH_5TEJ__) && \
- !defined(__ARM_ARCH_6__) && \
- !defined(__ARM_ARCH_6J__) && \
- !defined(__ARM_ARCH_6K__) && \
- !defined(__ARM_ARCH_6Z__) && \
- !defined(__ARM_ARCH_6ZK__) && \
- !defined(__ARM_ARCH_6T2__)
-
+ !defined(__ARM_ARCH_5__) && \
+ !defined(__ARM_ARCH_5T__) && \
+ !defined(__ARM_ARCH_5TE__) && \
+ !defined(__ARM_ARCH_5TEJ__) && \
+ !defined(__ARM_ARCH_6__) && \
+ !defined(__ARM_ARCH_6J__) && \
+ !defined(__ARM_ARCH_6K__) && \
+ !defined(__ARM_ARCH_6Z__) && \
+ !defined(__ARM_ARCH_6ZK__) && \
+ !defined(__ARM_ARCH_6T2__)
+
#if __GNUC__
#define ATTRIBUTE_PACKED __attribute__((__packed__))
#else
#define ATTRIBUTE_PACKED
#endif
-
+
namespace base {
namespace internal {
-
+
struct Unaligned16Struct {
uint16 value;
uint8 dummy; // To make the size non-power-of-two.
@@ -200,59 +200,59 @@ struct Unaligned32Struct {
(_val))
// TODO: NEON supports unaligned 64-bit loads and stores.
-// See if that would be more efficient on platforms supporting it,
-// at least for copies.
-
-inline uint64 UNALIGNED_LOAD64(const void *p) {
- uint64 t;
- memcpy(&t, p, sizeof t);
- return t;
-}
-
-inline void UNALIGNED_STORE64(void *p, uint64 v) {
- memcpy(p, &v, sizeof v);
-}
-
-#else
-
-// These functions are provided for architectures that don't support
-// unaligned loads and stores.
-
-inline uint16 UNALIGNED_LOAD16(const void *p) {
- uint16 t;
- memcpy(&t, p, sizeof t);
- return t;
-}
-
-inline uint32 UNALIGNED_LOAD32(const void *p) {
- uint32 t;
- memcpy(&t, p, sizeof t);
- return t;
-}
-
-inline uint64 UNALIGNED_LOAD64(const void *p) {
- uint64 t;
- memcpy(&t, p, sizeof t);
- return t;
-}
-
-inline void UNALIGNED_STORE16(void *p, uint16 v) {
- memcpy(p, &v, sizeof v);
-}
-
-inline void UNALIGNED_STORE32(void *p, uint32 v) {
- memcpy(p, &v, sizeof v);
-}
-
-inline void UNALIGNED_STORE64(void *p, uint64 v) {
- memcpy(p, &v, sizeof v);
-}
-
-#endif
-
+// See if that would be more efficient on platforms supporting it,
+// at least for copies.
+
+inline uint64 UNALIGNED_LOAD64(const void *p) {
+ uint64 t;
+ memcpy(&t, p, sizeof t);
+ return t;
+}
+
+inline void UNALIGNED_STORE64(void *p, uint64 v) {
+ memcpy(p, &v, sizeof v);
+}
+
+#else
+
+// These functions are provided for architectures that don't support
+// unaligned loads and stores.
+
+inline uint16 UNALIGNED_LOAD16(const void *p) {
+ uint16 t;
+ memcpy(&t, p, sizeof t);
+ return t;
+}
+
+inline uint32 UNALIGNED_LOAD32(const void *p) {
+ uint32 t;
+ memcpy(&t, p, sizeof t);
+ return t;
+}
+
+inline uint64 UNALIGNED_LOAD64(const void *p) {
+ uint64 t;
+ memcpy(&t, p, sizeof t);
+ return t;
+}
+
+inline void UNALIGNED_STORE16(void *p, uint16 v) {
+ memcpy(p, &v, sizeof v);
+}
+
+inline void UNALIGNED_STORE32(void *p, uint32 v) {
+ memcpy(p, &v, sizeof v);
+}
+
+inline void UNALIGNED_STORE64(void *p, uint64 v) {
+ memcpy(p, &v, sizeof v);
+}
+
+#endif
+
// The following guarantees declaration of the byte swap functions.
#if defined(SNAPPY_IS_BIG_ENDIAN)
-
+
#ifdef HAVE_SYS_BYTEORDER_H
#include <sys/byteorder.h>
#endif
@@ -293,8 +293,8 @@ inline void UNALIGNED_STORE64(void *p, uint64 v) {
inline uint16 bswap_16(uint16 x) {
return (x << 8) | (x >> 8);
-}
-
+}
+
inline uint32 bswap_32(uint32 x) {
x = ((x & 0xff00ff00UL) >> 8) | ((x & 0x00ff00ffUL) << 8);
return (x >> 16) | (x << 16);
@@ -310,28 +310,28 @@ inline uint64 bswap_64(uint64 x) {
#endif // defined(SNAPPY_IS_BIG_ENDIAN)
-// Convert to little-endian storage, opposite of network format.
-// Convert x from host to little endian: x = LittleEndian.FromHost(x);
-// convert x from little endian to host: x = LittleEndian.ToHost(x);
-//
-// Store values into unaligned memory converting to little endian order:
-// LittleEndian.Store16(p, x);
-//
-// Load unaligned values stored in little endian converting to host order:
-// x = LittleEndian.Load16(p);
-class LittleEndian {
- public:
- // Conversion functions.
+// Convert to little-endian storage, opposite of network format.
+// Convert x from host to little endian: x = LittleEndian.FromHost(x);
+// convert x from little endian to host: x = LittleEndian.ToHost(x);
+//
+// Store values into unaligned memory converting to little endian order:
+// LittleEndian.Store16(p, x);
+//
+// Load unaligned values stored in little endian converting to host order:
+// x = LittleEndian.Load16(p);
+class LittleEndian {
+ public:
+ // Conversion functions.
#if defined(SNAPPY_IS_BIG_ENDIAN)
-
+
static uint16 FromHost16(uint16 x) { return bswap_16(x); }
static uint16 ToHost16(uint16 x) { return bswap_16(x); }
-
+
static uint32 FromHost32(uint32 x) { return bswap_32(x); }
static uint32 ToHost32(uint32 x) { return bswap_32(x); }
- static bool IsLittleEndian() { return false; }
-
+ static bool IsLittleEndian() { return false; }
+
#else // !defined(SNAPPY_IS_BIG_ENDIAN)
static uint16 FromHost16(uint16 x) { return x; }
@@ -344,50 +344,50 @@ class LittleEndian {
#endif // !defined(SNAPPY_IS_BIG_ENDIAN)
- // Functions to do unaligned loads and stores in little-endian order.
- static uint16 Load16(const void *p) {
- return ToHost16(UNALIGNED_LOAD16(p));
- }
-
- static void Store16(void *p, uint16 v) {
- UNALIGNED_STORE16(p, FromHost16(v));
- }
-
- static uint32 Load32(const void *p) {
- return ToHost32(UNALIGNED_LOAD32(p));
- }
-
- static void Store32(void *p, uint32 v) {
- UNALIGNED_STORE32(p, FromHost32(v));
- }
-};
-
-// Some bit-manipulation functions.
-class Bits {
- public:
+ // Functions to do unaligned loads and stores in little-endian order.
+ static uint16 Load16(const void *p) {
+ return ToHost16(UNALIGNED_LOAD16(p));
+ }
+
+ static void Store16(void *p, uint16 v) {
+ UNALIGNED_STORE16(p, FromHost16(v));
+ }
+
+ static uint32 Load32(const void *p) {
+ return ToHost32(UNALIGNED_LOAD32(p));
+ }
+
+ static void Store32(void *p, uint32 v) {
+ UNALIGNED_STORE32(p, FromHost32(v));
+ }
+};
+
+// Some bit-manipulation functions.
+class Bits {
+ public:
// Return floor(log2(n)) for positive integer n.
static int Log2FloorNonZero(uint32 n);
- // Return floor(log2(n)) for positive integer n. Returns -1 iff n == 0.
- static int Log2Floor(uint32 n);
-
- // Return the first set least / most significant bit, 0-indexed. Returns an
- // undefined value if n == 0. FindLSBSetNonZero() is similar to ffs() except
- // that it's 0-indexed.
- static int FindLSBSetNonZero(uint32 n);
+ // Return floor(log2(n)) for positive integer n. Returns -1 iff n == 0.
+ static int Log2Floor(uint32 n);
+
+ // Return the first set least / most significant bit, 0-indexed. Returns an
+ // undefined value if n == 0. FindLSBSetNonZero() is similar to ffs() except
+ // that it's 0-indexed.
+ static int FindLSBSetNonZero(uint32 n);
#if defined(ARCH_K8) || defined(ARCH_PPC) || defined(ARCH_ARM)
- static int FindLSBSetNonZero64(uint64 n);
+ static int FindLSBSetNonZero64(uint64 n);
#endif // defined(ARCH_K8) || defined(ARCH_PPC) || defined(ARCH_ARM)
-
- private:
+
+ private:
// No copying
Bits(const Bits&);
void operator=(const Bits&);
-};
-
-#ifdef HAVE_BUILTIN_CTZ
-
+};
+
+#ifdef HAVE_BUILTIN_CTZ
+
inline int Bits::Log2FloorNonZero(uint32 n) {
assert(n != 0);
// (31 ^ x) is equivalent to (31 - x) for x in [0, 31]. An easy proof
@@ -399,22 +399,22 @@ inline int Bits::Log2FloorNonZero(uint32 n) {
return 31 ^ __builtin_clz(n);
}
-inline int Bits::Log2Floor(uint32 n) {
+inline int Bits::Log2Floor(uint32 n) {
return (n == 0) ? -1 : Bits::Log2FloorNonZero(n);
-}
-
-inline int Bits::FindLSBSetNonZero(uint32 n) {
+}
+
+inline int Bits::FindLSBSetNonZero(uint32 n) {
assert(n != 0);
- return __builtin_ctz(n);
-}
-
+ return __builtin_ctz(n);
+}
+
#if defined(ARCH_K8) || defined(ARCH_PPC) || defined(ARCH_ARM)
-inline int Bits::FindLSBSetNonZero64(uint64 n) {
+inline int Bits::FindLSBSetNonZero64(uint64 n) {
assert(n != 0);
- return __builtin_ctzll(n);
-}
+ return __builtin_ctzll(n);
+}
#endif // defined(ARCH_K8) || defined(ARCH_PPC) || defined(ARCH_ARM)
-
+
#elif defined(_MSC_VER)
inline int Bits::Log2FloorNonZero(uint32 n) {
@@ -449,158 +449,158 @@ inline int Bits::FindLSBSetNonZero64(uint64 n) {
}
#endif // defined(ARCH_K8) || defined(ARCH_PPC) || defined(ARCH_ARM)
-#else // Portable versions.
-
+#else // Portable versions.
+
inline int Bits::Log2FloorNonZero(uint32 n) {
assert(n != 0);
- int log = 0;
- uint32 value = n;
- for (int i = 4; i >= 0; --i) {
- int shift = (1 << i);
- uint32 x = value >> shift;
- if (x != 0) {
- value = x;
- log += shift;
- }
- }
- assert(value == 1);
- return log;
-}
-
+ int log = 0;
+ uint32 value = n;
+ for (int i = 4; i >= 0; --i) {
+ int shift = (1 << i);
+ uint32 x = value >> shift;
+ if (x != 0) {
+ value = x;
+ log += shift;
+ }
+ }
+ assert(value == 1);
+ return log;
+}
+
inline int Bits::Log2Floor(uint32 n) {
return (n == 0) ? -1 : Bits::Log2FloorNonZero(n);
}
-inline int Bits::FindLSBSetNonZero(uint32 n) {
+inline int Bits::FindLSBSetNonZero(uint32 n) {
assert(n != 0);
- int rc = 31;
- for (int i = 4, shift = 1 << 4; i >= 0; --i) {
- const uint32 x = n << shift;
- if (x != 0) {
- n = x;
- rc -= shift;
- }
- shift >>= 1;
- }
- return rc;
-}
-
+ int rc = 31;
+ for (int i = 4, shift = 1 << 4; i >= 0; --i) {
+ const uint32 x = n << shift;
+ if (x != 0) {
+ n = x;
+ rc -= shift;
+ }
+ shift >>= 1;
+ }
+ return rc;
+}
+
#if defined(ARCH_K8) || defined(ARCH_PPC) || defined(ARCH_ARM)
-// FindLSBSetNonZero64() is defined in terms of FindLSBSetNonZero().
-inline int Bits::FindLSBSetNonZero64(uint64 n) {
+// FindLSBSetNonZero64() is defined in terms of FindLSBSetNonZero().
+inline int Bits::FindLSBSetNonZero64(uint64 n) {
assert(n != 0);
- const uint32 bottombits = static_cast<uint32>(n);
- if (bottombits == 0) {
- // Bottom bits are zero, so scan in top bits
- return 32 + FindLSBSetNonZero(static_cast<uint32>(n >> 32));
- } else {
- return FindLSBSetNonZero(bottombits);
- }
-}
+ const uint32 bottombits = static_cast<uint32>(n);
+ if (bottombits == 0) {
+ // Bottom bits are zero, so scan in top bits
+ return 32 + FindLSBSetNonZero(static_cast<uint32>(n >> 32));
+ } else {
+ return FindLSBSetNonZero(bottombits);
+ }
+}
#endif // defined(ARCH_K8) || defined(ARCH_PPC) || defined(ARCH_ARM)
-
-#endif // End portable versions.
-
-// Variable-length integer encoding.
-class Varint {
- public:
- // Maximum lengths of varint encoding of uint32.
- static const int kMax32 = 5;
-
- // Attempts to parse a varint32 from a prefix of the bytes in [ptr,limit-1].
- // Never reads a character at or beyond limit. If a valid/terminated varint32
- // was found in the range, stores it in *OUTPUT and returns a pointer just
- // past the last byte of the varint32. Else returns NULL. On success,
- // "result <= limit".
- static const char* Parse32WithLimit(const char* ptr, const char* limit,
- uint32* OUTPUT);
-
- // REQUIRES "ptr" points to a buffer of length sufficient to hold "v".
- // EFFECTS Encodes "v" into "ptr" and returns a pointer to the
- // byte just past the last encoded byte.
- static char* Encode32(char* ptr, uint32 v);
-
- // EFFECTS Appends the varint representation of "value" to "*s".
+
+#endif // End portable versions.
+
+// Variable-length integer encoding.
+class Varint {
+ public:
+ // Maximum lengths of varint encoding of uint32.
+ static const int kMax32 = 5;
+
+ // Attempts to parse a varint32 from a prefix of the bytes in [ptr,limit-1].
+ // Never reads a character at or beyond limit. If a valid/terminated varint32
+ // was found in the range, stores it in *OUTPUT and returns a pointer just
+ // past the last byte of the varint32. Else returns NULL. On success,
+ // "result <= limit".
+ static const char* Parse32WithLimit(const char* ptr, const char* limit,
+ uint32* OUTPUT);
+
+ // REQUIRES "ptr" points to a buffer of length sufficient to hold "v".
+ // EFFECTS Encodes "v" into "ptr" and returns a pointer to the
+ // byte just past the last encoded byte.
+ static char* Encode32(char* ptr, uint32 v);
+
+ // EFFECTS Appends the varint representation of "value" to "*s".
static void Append32(std::string* s, uint32 value);
-};
-
-inline const char* Varint::Parse32WithLimit(const char* p,
- const char* l,
- uint32* OUTPUT) {
- const unsigned char* ptr = reinterpret_cast<const unsigned char*>(p);
- const unsigned char* limit = reinterpret_cast<const unsigned char*>(l);
- uint32 b, result;
- if (ptr >= limit) return NULL;
- b = *(ptr++); result = b & 127; if (b < 128) goto done;
- if (ptr >= limit) return NULL;
- b = *(ptr++); result |= (b & 127) << 7; if (b < 128) goto done;
- if (ptr >= limit) return NULL;
- b = *(ptr++); result |= (b & 127) << 14; if (b < 128) goto done;
- if (ptr >= limit) return NULL;
- b = *(ptr++); result |= (b & 127) << 21; if (b < 128) goto done;
- if (ptr >= limit) return NULL;
- b = *(ptr++); result |= (b & 127) << 28; if (b < 16) goto done;
- return NULL; // Value is too long to be a varint32
- done:
- *OUTPUT = result;
- return reinterpret_cast<const char*>(ptr);
-}
-
-inline char* Varint::Encode32(char* sptr, uint32 v) {
- // Operate on characters as unsigneds
- unsigned char* ptr = reinterpret_cast<unsigned char*>(sptr);
- static const int B = 128;
- if (v < (1<<7)) {
- *(ptr++) = v;
- } else if (v < (1<<14)) {
- *(ptr++) = v | B;
- *(ptr++) = v>>7;
- } else if (v < (1<<21)) {
- *(ptr++) = v | B;
- *(ptr++) = (v>>7) | B;
- *(ptr++) = v>>14;
- } else if (v < (1<<28)) {
- *(ptr++) = v | B;
- *(ptr++) = (v>>7) | B;
- *(ptr++) = (v>>14) | B;
- *(ptr++) = v>>21;
- } else {
- *(ptr++) = v | B;
- *(ptr++) = (v>>7) | B;
- *(ptr++) = (v>>14) | B;
- *(ptr++) = (v>>21) | B;
- *(ptr++) = v>>28;
- }
- return reinterpret_cast<char*>(ptr);
-}
-
+};
+
+inline const char* Varint::Parse32WithLimit(const char* p,
+ const char* l,
+ uint32* OUTPUT) {
+ const unsigned char* ptr = reinterpret_cast<const unsigned char*>(p);
+ const unsigned char* limit = reinterpret_cast<const unsigned char*>(l);
+ uint32 b, result;
+ if (ptr >= limit) return NULL;
+ b = *(ptr++); result = b & 127; if (b < 128) goto done;
+ if (ptr >= limit) return NULL;
+ b = *(ptr++); result |= (b & 127) << 7; if (b < 128) goto done;
+ if (ptr >= limit) return NULL;
+ b = *(ptr++); result |= (b & 127) << 14; if (b < 128) goto done;
+ if (ptr >= limit) return NULL;
+ b = *(ptr++); result |= (b & 127) << 21; if (b < 128) goto done;
+ if (ptr >= limit) return NULL;
+ b = *(ptr++); result |= (b & 127) << 28; if (b < 16) goto done;
+ return NULL; // Value is too long to be a varint32
+ done:
+ *OUTPUT = result;
+ return reinterpret_cast<const char*>(ptr);
+}
+
+inline char* Varint::Encode32(char* sptr, uint32 v) {
+ // Operate on characters as unsigneds
+ unsigned char* ptr = reinterpret_cast<unsigned char*>(sptr);
+ static const int B = 128;
+ if (v < (1<<7)) {
+ *(ptr++) = v;
+ } else if (v < (1<<14)) {
+ *(ptr++) = v | B;
+ *(ptr++) = v>>7;
+ } else if (v < (1<<21)) {
+ *(ptr++) = v | B;
+ *(ptr++) = (v>>7) | B;
+ *(ptr++) = v>>14;
+ } else if (v < (1<<28)) {
+ *(ptr++) = v | B;
+ *(ptr++) = (v>>7) | B;
+ *(ptr++) = (v>>14) | B;
+ *(ptr++) = v>>21;
+ } else {
+ *(ptr++) = v | B;
+ *(ptr++) = (v>>7) | B;
+ *(ptr++) = (v>>14) | B;
+ *(ptr++) = (v>>21) | B;
+ *(ptr++) = v>>28;
+ }
+ return reinterpret_cast<char*>(ptr);
+}
+
// If you know the internal layout of the std::string in use, you can
-// replace this function with one that resizes the string without
-// filling the new space with zeros (if applicable) --
-// it will be non-portable but faster.
+// replace this function with one that resizes the string without
+// filling the new space with zeros (if applicable) --
+// it will be non-portable but faster.
inline void STLStringResizeUninitialized(std::string* s, size_t new_size) {
s->resize(new_size);
-}
-
-// Return a mutable char* pointing to a string's internal buffer,
-// which may not be null-terminated. Writing through this pointer will
-// modify the string.
-//
-// string_as_array(&str)[i] is valid for 0 <= i < str.size() until the
-// next call to a string method that invalidates iterators.
-//
-// As of 2006-04, there is no standard-blessed way of getting a
-// mutable reference to a string's internal buffer. However, issue 530
-// (http://www.open-std.org/JTC1/SC22/WG21/docs/lwg-defects.html#530)
-// proposes this as the method. It will officially be part of the standard
-// for C++0x. This should already work on all current implementations.
+}
+
+// Return a mutable char* pointing to a string's internal buffer,
+// which may not be null-terminated. Writing through this pointer will
+// modify the string.
+//
+// string_as_array(&str)[i] is valid for 0 <= i < str.size() until the
+// next call to a string method that invalidates iterators.
+//
+// As of 2006-04, there is no standard-blessed way of getting a
+// mutable reference to a string's internal buffer. However, issue 530
+// (http://www.open-std.org/JTC1/SC22/WG21/docs/lwg-defects.html#530)
+// proposes this as the method. It will officially be part of the standard
+// for C++0x. This should already work on all current implementations.
inline char* string_as_array(std::string* str) {
return str->empty() ? NULL : &*str->begin();
-}
-
-} // namespace snappy
-
+}
+
+} // namespace snappy
+
#endif // THIRD_PARTY_SNAPPY_OPENSOURCE_SNAPPY_STUBS_INTERNAL_H_