Implement a dynamically growing memory log buffer with an upper limit.

test/cctest/test-log.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 //
 // Tests of logging functions from log.h
 
 #ifdef ENABLE_LOGGING_AND_PROFILING
 
 #include "v8.h"
 
 #include "log.h"
 #include "cctest.h"
@@ skipping 39 matching lines @@
   const char* line_1 = "aaa,\"bbb\"\n";
   const int line_1_len = strlen(line_1);
   // Still smaller than log message length.
   CHECK_EQ(0, Logger::GetLogLines(0, log_lines, line_1_len - 1));
   // The exact size.
   CHECK_EQ(line_1_len, Logger::GetLogLines(0, log_lines, line_1_len));
   CHECK_EQ(line_1, log_lines);
   memset(log_lines, 0, sizeof(log_lines));
   // A bit more than the first line length.
   CHECK_EQ(line_1_len, Logger::GetLogLines(0, log_lines, line_1_len + 3));
+  log_lines[line_1_len] = '\0';
   CHECK_EQ(line_1, log_lines);
   memset(log_lines, 0, sizeof(log_lines));
   const char* line_2 = "cccc,\"dddd\"\n";
   const int line_2_len = strlen(line_2);
   // Now start with line_2 beginning.
   CHECK_EQ(0, Logger::GetLogLines(line_1_len, log_lines, 0));
   CHECK_EQ(0, Logger::GetLogLines(line_1_len, log_lines, 3));
   CHECK_EQ(0, Logger::GetLogLines(line_1_len, log_lines, line_2_len - 1));
   CHECK_EQ(line_2_len, Logger::GetLogLines(line_1_len, log_lines, line_2_len));
   CHECK_EQ(line_2, log_lines);
@@ skipping 628 matching lines @@
   // Make sure that all log data is written prior crash due to CHECK failure.
   fflush(stdout);
   CHECK(results_equal);
 
   env->Exit();
   Logger::TearDown();
   i::FLAG_always_compact = saved_always_compact;
 }
 
 #endif  // ENABLE_LOGGING_AND_PROFILING