360 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			360 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===-- 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 {
 | |
| 
 | |
| 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, bool uppercase) {
 | |
|   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]);
 | |
|     digit = (digit < 10) ? '0' + digit : (uppercase ? 'A' : 'a') + digit - 10;
 | |
|     result += AppendChar(buff, buff_end, digit);
 | |
|   }
 | |
|   return result;
 | |
| }
 | |
| 
 | |
| static int AppendUnsigned(char **buff, const char *buff_end, u64 num, u8 base,
 | |
|                           u8 minimal_num_length, bool pad_with_zero,
 | |
|                           bool uppercase) {
 | |
|   return AppendNumber(buff, buff_end, num, base, minimal_num_length,
 | |
|                       pad_with_zero, false /* negative */, uppercase);
 | |
| }
 | |
| 
 | |
| 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,
 | |
|                       false /* uppercase */);
 | |
| }
 | |
| 
 | |
| 
 | |
| // Use the fact that explicitly requesting 0 width (%0s) results in UB and
 | |
| // interpret width == 0 as "no width requested":
 | |
| // width == 0 - no width requested
 | |
| // width  < 0 - left-justify s within and pad it to -width chars, if necessary
 | |
| // width  > 0 - right-justify s, not implemented yet
 | |
| static int AppendString(char **buff, const char *buff_end, int width,
 | |
|                         int max_chars, const char *s) {
 | |
|   if (!s)
 | |
|     s = "<null>";
 | |
|   int result = 0;
 | |
|   for (; *s; s++) {
 | |
|     if (max_chars >= 0 && result >= max_chars)
 | |
|       break;
 | |
|     result += AppendChar(buff, buff_end, *s);
 | |
|   }
 | |
|   // Only the left justified strings are supported.
 | |
|   while (width < -result)
 | |
|     result += AppendChar(buff, buff_end, ' ');
 | |
|   return result;
 | |
| }
 | |
| 
 | |
| static int AppendPointer(char **buff, const char *buff_end, u64 ptr_value) {
 | |
|   int result = 0;
 | |
|   result += AppendString(buff, buff_end, 0, -1, "0x");
 | |
|   result += AppendUnsigned(buff, buff_end, ptr_value, 16,
 | |
|                            SANITIZER_POINTER_FORMAT_LENGTH,
 | |
|                            true /* pad_with_zero */, false /* uppercase */);
 | |
|   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,X}; %p; "
 | |
|       "%[-]([0-9]*)?(\\.\\*)?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 left_justified = *cur == '-';
 | |
|     if (left_justified)
 | |
|       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;
 | |
|     const bool have_length = have_z || have_ll;
 | |
|     const bool have_flags = have_width || have_length;
 | |
|     // At the moment only %s supports precision and left-justification.
 | |
|     CHECK(!((precision >= 0 || left_justified) && *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':
 | |
|       case 'X': {
 | |
|         uval = have_ll ? va_arg(args, u64)
 | |
|              : have_z ? va_arg(args, uptr)
 | |
|              : va_arg(args, unsigned);
 | |
|         bool uppercase = (*cur == 'X');
 | |
|         result += AppendUnsigned(&buff, buff_end, uval, (*cur == 'u') ? 10 : 16,
 | |
|                                  width, pad_with_zero, uppercase);
 | |
|         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_length, kPrintfFormatsHelp);
 | |
|         // Only left-justified width is supported.
 | |
|         CHECK(!have_width || left_justified);
 | |
|         result += AppendString(&buff, buff_end, left_justified ? -width : width,
 | |
|                                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_GO && defined(TSAN_EXTERNAL_HOOKS)
 | |
| // Implementation must be defined in frontend.
 | |
| extern "C" void OnPrint(const char *str);
 | |
| #else
 | |
| SANITIZER_INTERFACE_WEAK_DEF(void, OnPrint, const char *str) {
 | |
|   (void)str;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| static void CallPrintfAndReportCallback(const char *str) {
 | |
|   OnPrint(str);
 | |
|   if (PrintfAndReportCallback)
 | |
|     PrintfAndReportCallback(str);
 | |
| }
 | |
| 
 | |
| static void NOINLINE SharedPrintfCodeNoBuffer(bool append_pid,
 | |
|                                               char *local_buffer,
 | |
|                                               int buffer_size,
 | |
|                                               const char *format,
 | |
|                                               va_list args) {
 | |
|   va_list args2;
 | |
|   va_copy(args2, args);
 | |
|   const int kLen = 16 * 1024;
 | |
|   int needed_length;
 | |
|   char *buffer = 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;
 | |
|     // Check that data fits into the current buffer.
 | |
| #   define CHECK_NEEDED_LENGTH \
 | |
|       if (needed_length >= buffer_size) { \
 | |
|         if (!use_mmap) continue; \
 | |
|         RAW_CHECK_MSG(needed_length < kLen, \
 | |
|                       "Buffer in Report is too short!\n"); \
 | |
|       }
 | |
|     // Fuchsia's logging infrastructure always keeps track of the logging
 | |
|     // process, thread, and timestamp, so never prepend such information.
 | |
|     if (!SANITIZER_FUCHSIA && append_pid) {
 | |
|       int pid = internal_getpid();
 | |
|       const char *exe_name = GetProcessName();
 | |
|       if (common_flags()->log_exe_name && exe_name) {
 | |
|         needed_length += internal_snprintf(buffer, buffer_size,
 | |
|                                            "==%s", exe_name);
 | |
|         CHECK_NEEDED_LENGTH
 | |
|       }
 | |
|       needed_length += internal_snprintf(
 | |
|           buffer + needed_length, buffer_size - needed_length, "==%d==", pid);
 | |
|       CHECK_NEEDED_LENGTH
 | |
|     }
 | |
|     needed_length += VSNPrintf(buffer + needed_length,
 | |
|                                buffer_size - needed_length, format, args);
 | |
|     CHECK_NEEDED_LENGTH
 | |
|     // If the message fit into the buffer, print it and exit.
 | |
|     break;
 | |
| #   undef CHECK_NEEDED_LENGTH
 | |
|   }
 | |
|   RawWrite(buffer);
 | |
| 
 | |
|   // Remove color sequences from the message.
 | |
|   RemoveANSIEscapeSequencesFromString(buffer);
 | |
|   CallPrintfAndReportCallback(buffer);
 | |
|   LogMessageOnPrintf(buffer);
 | |
| 
 | |
|   // If we had mapped any memory, clean up.
 | |
|   if (buffer != local_buffer)
 | |
|     UnmapOrDie((void *)buffer, buffer_size);
 | |
|   va_end(args2);
 | |
| }
 | |
| 
 | |
| static void NOINLINE SharedPrintfCode(bool append_pid, const char *format,
 | |
|                                       va_list args) {
 | |
|   // |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];
 | |
|   SharedPrintfCodeNoBuffer(append_pid, local_buffer, ARRAY_SIZE(local_buffer),
 | |
|                            format, args);
 | |
| }
 | |
| 
 | |
| 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
 |