diff options
Diffstat (limited to 'gold/output.cc')
| -rw-r--r-- | gold/output.cc | 116 |
1 files changed, 103 insertions, 13 deletions
diff --git a/gold/output.cc b/gold/output.cc index 5c1fae9..26f843c 100644 --- a/gold/output.cc +++ b/gold/output.cc @@ -1,6 +1,6 @@ // output.cc -- manage the output file for gold -// Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc. +// Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc. // Written by Ian Lance Taylor <iant@google.com>. // This file is part of gold. @@ -27,9 +27,13 @@ #include <cerrno> #include <fcntl.h> #include <unistd.h> -#include <sys/mman.h> #include <sys/stat.h> #include <algorithm> + +#ifdef HAVE_SYS_MMAN_H +#include <sys/mman.h> +#endif + #include "libiberty.h" #include "parameters.h" @@ -40,11 +44,71 @@ #include "descriptors.h" #include "output.h" +// For systems without mmap support. +#ifndef HAVE_MMAP +# define mmap gold_mmap +# define munmap gold_munmap +# define mremap gold_mremap +# ifndef MAP_FAILED +# define MAP_FAILED (reinterpret_cast<void*>(-1)) +# endif +# ifndef PROT_READ +# define PROT_READ 0 +# endif +# ifndef PROT_WRITE +# define PROT_WRITE 0 +# endif +# ifndef MAP_PRIVATE +# define MAP_PRIVATE 0 +# endif +# ifndef MAP_ANONYMOUS +# define MAP_ANONYMOUS 0 +# endif +# ifndef MAP_SHARED +# define MAP_SHARED 0 +# endif + +# ifndef ENOSYS +# define ENOSYS EINVAL +# endif + +static void * +gold_mmap(void *, size_t, int, int, int, off_t) +{ + errno = ENOSYS; + return MAP_FAILED; +} + +static int +gold_munmap(void *, size_t) +{ + errno = ENOSYS; + return -1; +} + +static void * +gold_mremap(void *, size_t, size_t, int) +{ + errno = ENOSYS; + return MAP_FAILED; +} + +#endif + +#if defined(HAVE_MMAP) && !defined(HAVE_MREMAP) +# define mremap gold_mremap +extern "C" void *gold_mremap(void *, size_t, size_t, int); +#endif + // Some BSD systems still use MAP_ANON instead of MAP_ANONYMOUS #ifndef MAP_ANONYMOUS # define MAP_ANONYMOUS MAP_ANON #endif +#ifndef MREMAP_MAYMOVE +# define MREMAP_MAYMOVE 1 +#endif + #ifndef HAVE_POSIX_FALLOCATE // A dummy, non general, version of posix_fallocate. Here we just set // the file size and hope that there is enough disk space. FIXME: We @@ -4415,6 +4479,7 @@ Output_file::Output_file(const char* name) file_size_(0), base_(NULL), map_is_anonymous_(false), + map_is_allocated_(false), is_temporary_(false) { } @@ -4522,10 +4587,23 @@ Output_file::resize(off_t file_size) // to unmap to flush to the file, then remap after growing the file. if (this->map_is_anonymous_) { - void* base = ::mremap(this->base_, this->file_size_, file_size, - MREMAP_MAYMOVE); - if (base == MAP_FAILED) - gold_fatal(_("%s: mremap: %s"), this->name_, strerror(errno)); + void* base; + if (!this->map_is_allocated_) + { + base = ::mremap(this->base_, this->file_size_, file_size, + MREMAP_MAYMOVE); + if (base == MAP_FAILED) + gold_fatal(_("%s: mremap: %s"), this->name_, strerror(errno)); + } + else + { + base = realloc(this->base_, file_size); + if (base == NULL) + gold_nomem(); + if (file_size > this->file_size_) + memset(static_cast<char*>(base) + this->file_size_, 0, + file_size - this->file_size_); + } this->base_ = static_cast<unsigned char*>(base); this->file_size_ = file_size; } @@ -4546,13 +4624,17 @@ Output_file::map_anonymous() { void* base = ::mmap(NULL, this->file_size_, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); - if (base != MAP_FAILED) + if (base == MAP_FAILED) { - this->map_is_anonymous_ = true; - this->base_ = static_cast<unsigned char*>(base); - return true; + base = malloc(this->file_size_); + if (base == NULL) + return false; + memset(base, 0, this->file_size_); + this->map_is_allocated_ = true; } - return false; + this->base_ = static_cast<unsigned char*>(base); + this->map_is_anonymous_ = true; + return true; } // Map the file into memory. Return whether the mapping succeeded. @@ -4624,8 +4706,16 @@ Output_file::map() void Output_file::unmap() { - if (::munmap(this->base_, this->file_size_) < 0) - gold_error(_("%s: munmap: %s"), this->name_, strerror(errno)); + if (this->map_is_anonymous_) + { + // We've already written out the data, so there is no reason to + // waste time unmapping or freeing the memory. + } + else + { + if (::munmap(this->base_, this->file_size_) < 0) + gold_error(_("%s: munmap: %s"), this->name_, strerror(errno)); + } this->base_ = NULL; } |