diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 01:47:29 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 01:47:29 +0000 |
commit | 0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d (patch) | |
tree | a31f07c9bcca9d56ce61e9a1ffd30ef350d513aa /memory/replace/logalloc/FdPrintf.cpp | |
parent | Initial commit. (diff) | |
download | firefox-esr-0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d.tar.xz firefox-esr-0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d.zip |
Adding upstream version 115.8.0esr.upstream/115.8.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'memory/replace/logalloc/FdPrintf.cpp')
-rw-r--r-- | memory/replace/logalloc/FdPrintf.cpp | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/memory/replace/logalloc/FdPrintf.cpp b/memory/replace/logalloc/FdPrintf.cpp new file mode 100644 index 0000000000..4a8e48af78 --- /dev/null +++ b/memory/replace/logalloc/FdPrintf.cpp @@ -0,0 +1,200 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include <cstdarg> + +#ifdef _WIN32 +# include <windows.h> +#else +# include <unistd.h> +#endif +#include <cmath> +#include <cstring> +#include "mozilla/Assertions.h" +#include "mozilla/Unused.h" +#include "FdPrintf.h" + +/* Template class allowing a limited number of increments on a value */ +template <typename T> +class CheckedIncrement { + public: + CheckedIncrement(T aValue, size_t aMaxIncrement) + : mValue(aValue), mMaxIncrement(aMaxIncrement) {} + + T operator++(int) { + if (!mMaxIncrement) { + MOZ_CRASH("overflow detected"); + } + mMaxIncrement--; + return mValue++; + } + + T& operator++() { + (*this)++; + return mValue; + } + + void advance(T end) { + // Only makes sense if T is a pointer type. + size_t diff = end - mValue; + if (diff > mMaxIncrement) { + MOZ_CRASH("overflow detected"); + } + mMaxIncrement -= diff; + mValue = end; + }; + + void rewind(T pos) { + size_t diff = mValue - pos; + mMaxIncrement += diff; + mValue = pos; + } + + operator T() { return mValue; } + T value() { return mValue; } + + private: + T mValue; + size_t mMaxIncrement; +}; + +template <typename T> +static unsigned NumDigits(T n) { + if (n < 1) { + // We want one digit, it will be 0. + return 1; + } + + double l = log10(static_cast<double>(n)); + double cl = ceil(l); + return l == cl ? unsigned(cl) + 1 : unsigned(cl); +} + +static void LeftPad(CheckedIncrement<char*>& b, size_t pad) { + while (pad-- > 0) { + *(b++) = ' '; + } +} + +// Write the digits into the buffer. +static void WriteDigits(CheckedIncrement<char*>& b, size_t i, + size_t num_digits) { + size_t x = pow(10, double(num_digits - 1)); + do { + *(b++) = "0123456789"[(i / x) % 10]; + x /= 10; + } while (x > 0); +} + +void FdPrintf(intptr_t aFd, const char* aFormat, ...) { + if (aFd == 0) { + return; + } + char buf[256]; + CheckedIncrement<char*> b(buf, sizeof(buf)); + CheckedIncrement<const char*> f(aFormat, strlen(aFormat) + 1); + va_list ap; + va_start(ap, aFormat); + while (true) { + switch (*f) { + case '\0': + goto out; + + case '%': { + // The start of the format specifier is used if this specifier is + // invalid. + const char* start = f; + + // Read the field width + f++; + char* end = nullptr; + size_t width = strtoul(f, &end, 10); + // If strtol can't find a number that's okay, that means 0 in our + // case, but we must advance f). + f.advance(end); + + switch (*f) { + case 'z': { + if (*(++f) == 'u') { + size_t i = va_arg(ap, size_t); + + size_t num_digits = NumDigits(i); + LeftPad(b, width > num_digits ? width - num_digits : 0); + WriteDigits(b, i, num_digits); + } else { + // If the format specifier is unknown then write out '%' and + // rewind to the beginning of the specifier causing it to be + // printed normally. + *(b++) = '%'; + f.rewind(start); + } + break; + } + + case 'p': { + intptr_t ptr = va_arg(ap, intptr_t); + *(b++) = '0'; + *(b++) = 'x'; + int x = sizeof(intptr_t) * 8; + bool wrote_msb = false; + do { + x -= 4; + size_t hex_digit = ptr >> x & 0xf; + if (hex_digit || wrote_msb) { + *(b++) = "0123456789abcdef"[hex_digit]; + wrote_msb = true; + } + } while (x > 0); + if (!wrote_msb) { + *(b++) = '0'; + } + break; + } + + case 's': { + const char* str = va_arg(ap, const char*); + size_t len = strlen(str); + + LeftPad(b, width > len ? width - len : 0); + + while (*str) { + *(b++) = *(str++); + } + + break; + } + + case '%': + // Print a single raw '%'. + *(b++) = '%'; + break; + + default: + // If the format specifier is unknown then write out '%' and + // rewind to the beginning of the specifier causing it to be + // printed normally. + *(b++) = '%'; + f.rewind(start); + break; + } + break; + } + default: + *(b++) = *f; + break; + } + f++; + } +out: +#ifdef _WIN32 + // See comment in FdPrintf.h as to why WriteFile is used. + DWORD written; + WriteFile(reinterpret_cast<HANDLE>(aFd), buf, b - buf, &written, nullptr); +#else + MOZ_UNUSED(write(aFd, buf, b - buf)); +#endif + va_end(ap); +} |