[ASan] Add process basename to log name and error message to

simplify analysis of sanitized systems logs.
    
Differential Revision: http://reviews.llvm.org/D7333

llvm-svn: 239134

compiler-rt/lib/sanitizer_common/sanitizer_common.cc

@@ -57,7 +57,13 @@ void ReportFile::ReopenIfNecessary() {
       CloseFile(fd);
   }
 
-  internal_snprintf(full_path, kMaxPathLength, "%s.%zu", path_prefix, pid);
+  const char *exe_name = GetBinaryBasename();
+  if (common_flags()->log_exe_name && exe_name) {
+    internal_snprintf(full_path, kMaxPathLength, "%s.%s.%zu", path_prefix,
+                      exe_name, pid);
+  } else {
+    internal_snprintf(full_path, kMaxPathLength, "%s.%zu", path_prefix, pid);
+  }
   fd = OpenFile(full_path, WrOnly);
   if (fd == kInvalidFd) {
     const char *ErrorMsgPrefix = "ERROR: Can't open file: ";

compiler-rt/lib/sanitizer_common/sanitizer_flags.inc

@@ -50,6 +50,10 @@ COMMON_FLAG(
     const char *, log_path, "stderr",
     "Write logs to \"log_path.pid\". The special values are \"stdout\" and "
     "\"stderr\". The default is \"stderr\".")
+COMMON_FLAG(
+    bool, log_exe_name, false,
+    "Mention name of executable when reporting error and "
+    "append executable name to logs (as in \"log_path.exe_name.pid\").")
 COMMON_FLAG(
     int, verbosity, 0,
     "Verbosity level (0 - silent, 1 - a bit of output, 2+ - more output).")

compiler-rt/lib/sanitizer_common/sanitizer_printf.cc

@@ -251,26 +251,32 @@ static void SharedPrintfCode(bool append_pid, const char *format,
       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"); \
+      }
     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");
+      const char *exe_name = GetBinaryBasename();
+      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);
-    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");
-    }
+    CHECK_NEEDED_LENGTH
     // If the message fit into the buffer, print it and exit.
     break;
+#   undef CHECK_NEEDED_LENGTH
   }
   RawWrite(buffer);
   AndroidLogWrite(buffer);

compiler-rt/test/asan/TestCases/verbose-log-path_test.cc

@@ -0,0 +1,21 @@
+// RUN: %clangxx_asan %s -o %T/verbose-log-path_test-binary
+
+// Good log_path.
+// RUN: rm -f %T/asan.log.*
+// RUN: env ASAN_OPTIONS=log_path=%T/asan.log:log_exe_name=1 not %run %T/verbose-log-path_test-binary 2> %t.out
+// RUN: FileCheck %s --check-prefix=CHECK-ERROR < %T/asan.log.verbose-log-path_test-binary.*
+
+// FIXME: only FreeBSD and Linux have verbose log paths now.
+// XFAIL: win32,android,darwin
+
+#include <stdlib.h>
+#include <string.h>
+int main(int argc, char **argv) {
+  if (argc > 2) return 0;
+  char *x = (char*)malloc(10);
+  memset(x, 0, 10);
+  int res = x[argc * 10];  // BOOOM
+  free(x);
+  return res;
+}
+// CHECK-ERROR: ERROR: AddressSanitizer