diff options
Diffstat (limited to 'src/util.cc')
| -rw-r--r-- | src/util.cc | 164 |
1 files changed, 157 insertions, 7 deletions
diff --git a/src/util.cc b/src/util.cc index 484b0c1..746d7ed 100644 --- a/src/util.cc +++ b/src/util.cc @@ -85,19 +85,33 @@ void Error(const char* msg, ...) { fprintf(stderr, "\n"); } -bool CanonicalizePath(string* path, string* err) { +bool CanonicalizePath(string* path, unsigned int* slash_bits, string* err) { METRIC_RECORD("canonicalize str"); size_t len = path->size(); char* str = 0; if (len > 0) str = &(*path)[0]; - if (!CanonicalizePath(str, &len, err)) + if (!CanonicalizePath(str, &len, slash_bits, err)) return false; path->resize(len); return true; } -bool CanonicalizePath(char* path, size_t* len, string* err) { +#ifdef _WIN32 +static unsigned int ShiftOverBit(int offset, unsigned int bits) { + // e.g. for |offset| == 2: + // | ... 9 8 7 6 5 4 3 2 1 0 | + // \_________________/ \_/ + // above below + // So we drop the bit at offset and move above "down" into its place. + unsigned int above = bits & ~((1 << (offset + 1)) - 1); + unsigned int below = bits & ((1 << offset) - 1); + return (above >> 1) | below; +} +#endif + +bool CanonicalizePath(char* path, size_t* len, unsigned int* slash_bits, + string* err) { // WARNING: this function is performance-critical; please benchmark // any changes you make to it. METRIC_RECORD("canonicalize path"); @@ -115,12 +129,37 @@ bool CanonicalizePath(char* path, size_t* len, string* err) { const char* src = start; const char* end = start + *len; +#ifdef _WIN32 + unsigned int bits = 0; + unsigned int bits_mask = 1; + int bits_offset = 0; + // Convert \ to /, setting a bit in |bits| for each \ encountered. + for (char* c = path; c < end; ++c) { + switch (*c) { + case '\\': + bits |= bits_mask; + *c = '/'; + // Intentional fallthrough. + case '/': + bits_mask <<= 1; + bits_offset++; + } + } + if (bits_offset > 32) { + *err = "too many path components"; + return false; + } + bits_offset = 0; +#endif + if (*src == '/') { #ifdef _WIN32 + bits_offset++; // network path starts with // if (*len > 1 && *(src + 1) == '/') { src += 2; dst += 2; + bits_offset++; } else { ++src; ++dst; @@ -136,6 +175,9 @@ bool CanonicalizePath(char* path, size_t* len, string* err) { if (src + 1 == end || src[1] == '/') { // '.' component; eliminate. src += 2; +#ifdef _WIN32 + bits = ShiftOverBit(bits_offset, bits); +#endif continue; } else if (src[1] == '.' && (src + 2 == end || src[2] == '/')) { // '..' component. Back up if possible. @@ -143,6 +185,11 @@ bool CanonicalizePath(char* path, size_t* len, string* err) { dst = components[component_count - 1]; src += 3; --component_count; +#ifdef _WIN32 + bits = ShiftOverBit(bits_offset, bits); + bits_offset--; + bits = ShiftOverBit(bits_offset, bits); +#endif } else { *dst++ = *src++; *dst++ = *src++; @@ -154,6 +201,9 @@ bool CanonicalizePath(char* path, size_t* len, string* err) { if (*src == '/') { src++; +#ifdef _WIN32 + bits = ShiftOverBit(bits_offset, bits); +#endif continue; } @@ -164,6 +214,9 @@ bool CanonicalizePath(char* path, size_t* len, string* err) { while (*src != '/' && src != end) *dst++ = *src++; +#ifdef _WIN32 + bits_offset++; +#endif *dst++ = *src++; // Copy '/' or final \0 character as well. } @@ -173,6 +226,11 @@ bool CanonicalizePath(char* path, size_t* len, string* err) { } *len = dst - start - 1; +#ifdef _WIN32 + *slash_bits = bits; +#else + *slash_bits = 0; +#endif return true; } @@ -280,7 +338,38 @@ void GetWin32EscapedString(const string& input, string* result) { } int ReadFile(const string& path, string* contents, string* err) { - FILE* f = fopen(path.c_str(), "r"); +#ifdef _WIN32 + // This makes a ninja run on a set of 1500 manifest files about 4% faster + // than using the generic fopen code below. + err->clear(); + HANDLE f = ::CreateFile(path.c_str(), + GENERIC_READ, + FILE_SHARE_READ, + NULL, + OPEN_EXISTING, + FILE_FLAG_SEQUENTIAL_SCAN, + NULL); + if (f == INVALID_HANDLE_VALUE) { + err->assign(GetLastErrorString()); + return -ENOENT; + } + + for (;;) { + DWORD len; + char buf[64 << 10]; + if (!::ReadFile(f, buf, sizeof(buf), &len, NULL)) { + err->assign(GetLastErrorString()); + contents->clear(); + return -1; + } + if (len == 0) + break; + contents->append(buf, len); + } + ::CloseHandle(f); + return 0; +#else + FILE* f = fopen(path.c_str(), "rb"); if (!f) { err->assign(strerror(errno)); return -errno; @@ -299,6 +388,7 @@ int ReadFile(const string& path, string* contents, string* err) { } fclose(f); return 0; +#endif } void SetCloseOnExec(int fd) { @@ -415,10 +505,70 @@ int GetProcessorCount() { } #if defined(_WIN32) || defined(__CYGWIN__) +static double CalculateProcessorLoad(uint64_t idle_ticks, uint64_t total_ticks) +{ + static uint64_t previous_idle_ticks = 0; + static uint64_t previous_total_ticks = 0; + static double previous_load = -0.0; + + uint64_t idle_ticks_since_last_time = idle_ticks - previous_idle_ticks; + uint64_t total_ticks_since_last_time = total_ticks - previous_total_ticks; + + bool first_call = (previous_total_ticks == 0); + bool ticks_not_updated_since_last_call = (total_ticks_since_last_time == 0); + + double load; + if (first_call || ticks_not_updated_since_last_call) { + load = previous_load; + } else { + // Calculate load. + double idle_to_total_ratio = + ((double)idle_ticks_since_last_time) / total_ticks_since_last_time; + double load_since_last_call = 1.0 - idle_to_total_ratio; + + // Filter/smooth result when possible. + if(previous_load > 0) { + load = 0.9 * previous_load + 0.1 * load_since_last_call; + } else { + load = load_since_last_call; + } + } + + previous_load = load; + previous_total_ticks = total_ticks; + previous_idle_ticks = idle_ticks; + + return load; +} + +static uint64_t FileTimeToTickCount(const FILETIME & ft) +{ + uint64_t high = (((uint64_t)(ft.dwHighDateTime)) << 32); + uint64_t low = ft.dwLowDateTime; + return (high | low); +} + double GetLoadAverage() { - // TODO(nicolas.despres@gmail.com): Find a way to implement it on Windows. - // Remember to also update Usage() when this is fixed. - return -0.0f; + FILETIME idle_time, kernel_time, user_time; + BOOL get_system_time_succeeded = + GetSystemTimes(&idle_time, &kernel_time, &user_time); + + double posix_compatible_load; + if (get_system_time_succeeded) { + uint64_t idle_ticks = FileTimeToTickCount(idle_time); + + // kernel_time from GetSystemTimes already includes idle_time. + uint64_t total_ticks = + FileTimeToTickCount(kernel_time) + FileTimeToTickCount(user_time); + + double processor_load = CalculateProcessorLoad(idle_ticks, total_ticks); + posix_compatible_load = processor_load * GetProcessorCount(); + + } else { + posix_compatible_load = -0.0; + } + + return posix_compatible_load; } #else double GetLoadAverage() { |