Parse /proc/self/maps lines better to handle variations between Linux kernels...

src/platform-linux.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 20 matching lines @@
 #include <semaphore.h>
 #include <signal.h>
 #include <sys/time.h>
 #include <sys/resource.h>
 #include <stdlib.h>
 
 // Ubuntu Dapper requires memory pages to be marked as
 // executable. Otherwise, OS raises an exception when executing code
 // in that page.
 #include <sys/types.h>  // mmap & munmap
-#include <sys/mman.h>  // mmap & munmap
-#include <sys/stat.h>  // open
+#include <sys/mman.h>   // mmap & munmap
+#include <sys/stat.h>   // open
 #include <sys/fcntl.h>  // open
-#include <unistd.h>  // getpagesize
-#include <execinfo.h>  // backtrace, backtrace_symbols
+#include <unistd.h>     // getpagesize
+#include <execinfo.h>   // backtrace, backtrace_symbols
+#include <strings.h>    // index
 #include <errno.h>
 #include <stdarg.h>
 
 #undef MAP_TYPE
 
 #include "v8.h"
 
 #include "platform.h"
 
 
@@ skipping 272 matching lines @@
     char buffer[MAP_LENGTH];
     int bytes_read = -1;
     do {
       bytes_read++;
       if (bytes_read >= MAP_LENGTH - 1)
         break;
       result = read(fd, buffer + bytes_read, 1);
       if (result < 1) break;
     } while (buffer[bytes_read] != '\n');
     buffer[bytes_read] = 0;
-    // There are 56 chars to ignore at this point in the line.
-    if (bytes_read < 56) continue;
     // Ignore mappings that are not executable.
     if (buffer[3] != 'x') continue;
+    char* start_of_path = index(buffer, '/');
+    // There may be no filename in this line.  Skip to next.
+    if (start_of_path == NULL) continue;
     buffer[bytes_read] = 0;
-    LOG(SharedLibraryEvent(buffer + 56, start, end));
+    LOG(SharedLibraryEvent(start_of_path, start, end));
   }
   close(fd);
 #endif
 }
 
 
 int OS::StackWalk(OS::StackFrame* frames, int frames_size) {
   void** addresses = NewArray<void*>(frames_size);
 
   int frames_count = backtrace(addresses, frames_size);
@@ skipping 323 matching lines @@
   }
 
   // This sampler is no longer the active sampler.
   active_sampler_ = NULL;
   active_ = false;
 }
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal