diff options
Diffstat (limited to 'contrib/compiler-rt/lib/sanitizer_common/sanitizer_printf.cc')
-rw-r--r-- | contrib/compiler-rt/lib/sanitizer_common/sanitizer_printf.cc | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/contrib/compiler-rt/lib/sanitizer_common/sanitizer_printf.cc b/contrib/compiler-rt/lib/sanitizer_common/sanitizer_printf.cc new file mode 100644 index 0000000..3be6723 --- /dev/null +++ b/contrib/compiler-rt/lib/sanitizer_common/sanitizer_printf.cc @@ -0,0 +1,325 @@ +//===-- sanitizer_printf.cc -----------------------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file is shared between AddressSanitizer and ThreadSanitizer. +// +// Internal printf function, used inside run-time libraries. +// We can't use libc printf because we intercept some of the functions used +// inside it. +//===----------------------------------------------------------------------===// + + +#include "sanitizer_common.h" +#include "sanitizer_flags.h" +#include "sanitizer_libc.h" + +#include <stdio.h> +#include <stdarg.h> + +#if SANITIZER_WINDOWS && defined(_MSC_VER) && _MSC_VER < 1800 && \ + !defined(va_copy) +# define va_copy(dst, src) ((dst) = (src)) +#endif + +namespace __sanitizer { + +StaticSpinMutex CommonSanitizerReportMutex; + +static int AppendChar(char **buff, const char *buff_end, char c) { + if (*buff < buff_end) { + **buff = c; + (*buff)++; + } + return 1; +} + +// Appends number in a given base to buffer. If its length is less than +// |minimal_num_length|, it is padded with leading zeroes or spaces, depending +// on the value of |pad_with_zero|. +static int AppendNumber(char **buff, const char *buff_end, u64 absolute_value, + u8 base, u8 minimal_num_length, bool pad_with_zero, + bool negative) { + uptr const kMaxLen = 30; + RAW_CHECK(base == 10 || base == 16); + RAW_CHECK(base == 10 || !negative); + RAW_CHECK(absolute_value || !negative); + RAW_CHECK(minimal_num_length < kMaxLen); + int result = 0; + if (negative && minimal_num_length) + --minimal_num_length; + if (negative && pad_with_zero) + result += AppendChar(buff, buff_end, '-'); + uptr num_buffer[kMaxLen]; + int pos = 0; + do { + RAW_CHECK_MSG((uptr)pos < kMaxLen, "AppendNumber buffer overflow"); + num_buffer[pos++] = absolute_value % base; + absolute_value /= base; + } while (absolute_value > 0); + if (pos < minimal_num_length) { + // Make sure compiler doesn't insert call to memset here. + internal_memset(&num_buffer[pos], 0, + sizeof(num_buffer[0]) * (minimal_num_length - pos)); + pos = minimal_num_length; + } + RAW_CHECK(pos > 0); + pos--; + for (; pos >= 0 && num_buffer[pos] == 0; pos--) { + char c = (pad_with_zero || pos == 0) ? '0' : ' '; + result += AppendChar(buff, buff_end, c); + } + if (negative && !pad_with_zero) result += AppendChar(buff, buff_end, '-'); + for (; pos >= 0; pos--) { + char digit = static_cast<char>(num_buffer[pos]); + result += AppendChar(buff, buff_end, (digit < 10) ? '0' + digit + : 'a' + digit - 10); + } + return result; +} + +static int AppendUnsigned(char **buff, const char *buff_end, u64 num, u8 base, + u8 minimal_num_length, bool pad_with_zero) { + return AppendNumber(buff, buff_end, num, base, minimal_num_length, + pad_with_zero, false /* negative */); +} + +static int AppendSignedDecimal(char **buff, const char *buff_end, s64 num, + u8 minimal_num_length, bool pad_with_zero) { + bool negative = (num < 0); + return AppendNumber(buff, buff_end, (u64)(negative ? -num : num), 10, + minimal_num_length, pad_with_zero, negative); +} + +static int AppendString(char **buff, const char *buff_end, int precision, + const char *s) { + if (s == 0) + s = "<null>"; + int result = 0; + for (; *s; s++) { + if (precision >= 0 && result >= precision) + break; + result += AppendChar(buff, buff_end, *s); + } + return result; +} + +static int AppendPointer(char **buff, const char *buff_end, u64 ptr_value) { + int result = 0; + result += AppendString(buff, buff_end, -1, "0x"); + result += AppendUnsigned(buff, buff_end, ptr_value, 16, + SANITIZER_POINTER_FORMAT_LENGTH, true); + return result; +} + +int VSNPrintf(char *buff, int buff_length, + const char *format, va_list args) { + static const char *kPrintfFormatsHelp = + "Supported Printf formats: %([0-9]*)?(z|ll)?{d,u,x}; %p; %(\\.\\*)?s; %c\n"; + RAW_CHECK(format); + RAW_CHECK(buff_length > 0); + const char *buff_end = &buff[buff_length - 1]; + const char *cur = format; + int result = 0; + for (; *cur; cur++) { + if (*cur != '%') { + result += AppendChar(&buff, buff_end, *cur); + continue; + } + cur++; + bool have_width = (*cur >= '0' && *cur <= '9'); + bool pad_with_zero = (*cur == '0'); + int width = 0; + if (have_width) { + while (*cur >= '0' && *cur <= '9') { + width = width * 10 + *cur++ - '0'; + } + } + bool have_precision = (cur[0] == '.' && cur[1] == '*'); + int precision = -1; + if (have_precision) { + cur += 2; + precision = va_arg(args, int); + } + bool have_z = (*cur == 'z'); + cur += have_z; + bool have_ll = !have_z && (cur[0] == 'l' && cur[1] == 'l'); + cur += have_ll * 2; + s64 dval; + u64 uval; + bool have_flags = have_width | have_z | have_ll; + // Only %s supports precision for now + CHECK(!(precision >= 0 && *cur != 's')); + switch (*cur) { + case 'd': { + dval = have_ll ? va_arg(args, s64) + : have_z ? va_arg(args, sptr) + : va_arg(args, int); + result += AppendSignedDecimal(&buff, buff_end, dval, width, + pad_with_zero); + break; + } + case 'u': + case 'x': { + uval = have_ll ? va_arg(args, u64) + : have_z ? va_arg(args, uptr) + : va_arg(args, unsigned); + result += AppendUnsigned(&buff, buff_end, uval, + (*cur == 'u') ? 10 : 16, width, pad_with_zero); + break; + } + case 'p': { + RAW_CHECK_MSG(!have_flags, kPrintfFormatsHelp); + result += AppendPointer(&buff, buff_end, va_arg(args, uptr)); + break; + } + case 's': { + RAW_CHECK_MSG(!have_flags, kPrintfFormatsHelp); + result += AppendString(&buff, buff_end, precision, va_arg(args, char*)); + break; + } + case 'c': { + RAW_CHECK_MSG(!have_flags, kPrintfFormatsHelp); + result += AppendChar(&buff, buff_end, va_arg(args, int)); + break; + } + case '%' : { + RAW_CHECK_MSG(!have_flags, kPrintfFormatsHelp); + result += AppendChar(&buff, buff_end, '%'); + break; + } + default: { + RAW_CHECK_MSG(false, kPrintfFormatsHelp); + } + } + } + RAW_CHECK(buff <= buff_end); + AppendChar(&buff, buff_end + 1, '\0'); + return result; +} + +static void (*PrintfAndReportCallback)(const char *); +void SetPrintfAndReportCallback(void (*callback)(const char *)) { + PrintfAndReportCallback = callback; +} + +// Can be overriden in frontend. +#if SANITIZER_SUPPORTS_WEAK_HOOKS +SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE +void OnPrint(const char *str) { + (void)str; +} +#elif defined(SANITIZER_GO) && defined(TSAN_EXTERNAL_HOOKS) +void OnPrint(const char *str); +#else +void OnPrint(const char *str) { + (void)str; +} +#endif + +static void CallPrintfAndReportCallback(const char *str) { + OnPrint(str); + if (PrintfAndReportCallback) + PrintfAndReportCallback(str); +} + +static void SharedPrintfCode(bool append_pid, const char *format, + va_list args) { + va_list args2; + va_copy(args2, args); + const int kLen = 16 * 1024; + // |local_buffer| is small enough not to overflow the stack and/or violate + // the stack limit enforced by TSan (-Wframe-larger-than=512). On the other + // hand, the bigger the buffer is, the more the chance the error report will + // fit into it. + char local_buffer[400]; + int needed_length; + char *buffer = local_buffer; + int buffer_size = ARRAY_SIZE(local_buffer); + // First try to print a message using a local buffer, and then fall back to + // mmaped buffer. + for (int use_mmap = 0; use_mmap < 2; use_mmap++) { + if (use_mmap) { + va_end(args); + va_copy(args, args2); + buffer = (char*)MmapOrDie(kLen, "Report"); + buffer_size = kLen; + } + needed_length = 0; + if (append_pid) { + int pid = internal_getpid(); + needed_length += internal_snprintf(buffer, buffer_size, "==%d==", pid); + if (needed_length >= buffer_size) { + // The pid doesn't fit into the current buffer. + if (!use_mmap) + continue; + RAW_CHECK_MSG(needed_length < kLen, "Buffer in Report is too short!\n"); + } + } + needed_length += VSNPrintf(buffer + needed_length, + buffer_size - needed_length, format, args); + if (needed_length >= buffer_size) { + // The message doesn't fit into the current buffer. + if (!use_mmap) + continue; + RAW_CHECK_MSG(needed_length < kLen, "Buffer in Report is too short!\n"); + } + // If the message fit into the buffer, print it and exit. + break; + } + RawWrite(buffer); + AndroidLogWrite(buffer); + CallPrintfAndReportCallback(buffer); + // If we had mapped any memory, clean up. + if (buffer != local_buffer) + UnmapOrDie((void *)buffer, buffer_size); + va_end(args2); +} + +FORMAT(1, 2) +void Printf(const char *format, ...) { + va_list args; + va_start(args, format); + SharedPrintfCode(false, format, args); + va_end(args); +} + +// Like Printf, but prints the current PID before the output string. +FORMAT(1, 2) +void Report(const char *format, ...) { + va_list args; + va_start(args, format); + SharedPrintfCode(true, format, args); + va_end(args); +} + +// Writes at most "length" symbols to "buffer" (including trailing '\0'). +// Returns the number of symbols that should have been written to buffer +// (not including trailing '\0'). Thus, the string is truncated +// iff return value is not less than "length". +FORMAT(3, 4) +int internal_snprintf(char *buffer, uptr length, const char *format, ...) { + va_list args; + va_start(args, format); + int needed_length = VSNPrintf(buffer, length, format, args); + va_end(args); + return needed_length; +} + +FORMAT(2, 3) +void InternalScopedString::append(const char *format, ...) { + CHECK_LT(length_, size()); + va_list args; + va_start(args, format); + VSNPrintf(data() + length_, size() - length_, format, args); + va_end(args); + length_ += internal_strlen(data() + length_); + CHECK_LT(length_, size()); +} + +} // namespace __sanitizer |