gas/

[deliverable/binutils-gdb.git] / gold / fileread.cc

diff --git a/gold/fileread.cc b/gold/fileread.cc
index 9b800e81fce8ffac2275582fd84b011e837c726c..d87f7731d50f10a406dd6b088629e3bffcaa8f7b 100644 (file)
--- a/gold/fileread.cc
+++ b/gold/fileread.cc
@@ -26,6 +26,7 @@
 #include <cerrno>
 #include <fcntl.h>
 #include <unistd.h>
+#include <sys/mman.h>
 
 #include "options.h"
 #include "dirsearch.h"
@@ -39,7 +40,14 @@ namespace gold
 File_read::View::~View()
 {
   gold_assert(!this->is_locked());
-  delete[] this->data_;
+  if (!this->mapped_)
+    delete[] this->data_;
+  else
+    {
+      if (::munmap(const_cast<unsigned char*>(this->data_), this->size_) != 0)
+        fprintf(stderr, _("%s: munmap failed: %s\n"),
+                program_name, strerror(errno));
+    }
 }
 
 void
@@ -136,6 +144,8 @@ File_read::unlock()
 {
   gold_assert(this->lock_count_ > 0);
   --this->lock_count_;
+  if (this->lock_count_ == 0)
+    this->clear_views(false);
 }
 
 bool
@@ -160,54 +170,44 @@ File_read::find_view(off_t start, off_t size)
 }
 
 // Read SIZE bytes from the file starting at offset START.  Read into
-// the buffer at P.  Return the number of bytes read, which should
-// always be at least SIZE except at the end of the file.
+// the buffer at P.
 
-off_t
+void
 File_read::do_read(off_t start, off_t size, void* p)
 {
   gold_assert(this->lock_count_ > 0);
 
+  off_t bytes;
   if (this->contents_ != NULL)
     {
-      off_t bytes = this->size_ - start;
-      if (bytes < 0)
-       bytes = 0;
-      else if (bytes > size)
-       bytes = size;
-      memcpy(p, this->contents_ + start, bytes);
-      return bytes;
+      bytes = this->size_ - start;
+      if (bytes >= size)
+       {
+         memcpy(p, this->contents_ + start, size);
+         return;
+       }
     }
-
-  off_t bytes = ::pread(this->descriptor_, p, size, start);
-  if (bytes < 0)
+  else
     {
-      fprintf(stderr, _("%s: %s: pread failed: %s\n"),
-             program_name, this->filename().c_str(), strerror(errno));
-      gold_exit(false);
-    }
-
-  return bytes;
-}
-
-// Read exactly SIZE bytes from the file starting at offset START.
-// Read into the buffer at P.
+      bytes = ::pread(this->descriptor_, p, size, start);
+      if (bytes == size)
+       return;
 
-void
-File_read::do_read_exact(off_t start, off_t size, void* p)
-{
-  off_t bytes = this->do_read(start, size, p);
-  if (bytes != size)
-    {
-      fprintf(stderr,
-             _("%s: %s: file too short: read only %lld of %lld "
-               "bytes at %lld\n"),
-             program_name, this->filename().c_str(),
-             static_cast<long long>(bytes),
-             static_cast<long long>(size),
-             static_cast<long long>(start));
-      gold_exit(false);
+      if (bytes < 0)
+       {
+         fprintf(stderr, _("%s: %s: pread failed: %s\n"),
+                 program_name, this->filename().c_str(), strerror(errno));
+         gold_exit(false);
+       }
     }
+
+  fprintf(stderr,
+         _("%s: %s: file too short: read only %lld of %lld bytes at %lld\n"),
+         program_name, this->filename().c_str(),
+         static_cast<long long>(bytes),
+         static_cast<long long>(size),
+         static_cast<long long>(start));
+  gold_exit(false);
 }
 
 // Read data from the file.
@@ -224,13 +224,13 @@ File_read::read(off_t start, off_t size, void* p)
       return;
     }
 
-  this->do_read_exact(start, size, p);
+  this->do_read(start, size, p);
 }
 
 // Find an existing view or make a new one.
 
 File_read::View*
-File_read::find_or_make_view(off_t start, off_t size)
+File_read::find_or_make_view(off_t start, off_t size, bool cache)
 {
   gold_assert(this->lock_count_ > 0);
 
@@ -245,7 +245,11 @@ File_read::find_or_make_view(off_t start, off_t size)
       // There was an existing view at this offset.
       File_read::View* v = ins.first->second;
       if (v->size() - (start - v->start()) >= size)
-       return v;
+       {
+         if (cache)
+           v->set_cache();
+         return v;
+       }
 
       // This view is not large enough.
       this->saved_views_.push_back(v);
@@ -262,11 +266,32 @@ File_read::find_or_make_view(off_t start, off_t size)
       gold_assert(psize >= size);
     }
 
-  unsigned char* p = new unsigned char[psize];
+  File_read::View* v;
 
-  this->do_read_exact(poff, psize, p);
+  if (this->contents_ != NULL)
+    {
+      unsigned char* p = new unsigned char[psize];
+      this->do_read(poff, psize, p);
+      v = new File_read::View(poff, psize, p, cache, false);
+    }
+  else
+    {
+      void* p = ::mmap(NULL, psize, PROT_READ, MAP_SHARED,
+                       this->descriptor_, poff);
+      if (p == MAP_FAILED)
+        {
+          fprintf(stderr, _("%s: %s: mmap offset %lld size %lld failed: %s\n"),
+                  program_name, this->filename().c_str(),
+                  static_cast<long long>(poff),
+                  static_cast<long long>(psize),
+                  strerror(errno));
+          gold_exit(false);
+        }
+
+      const unsigned char* pbytes = static_cast<const unsigned char*>(p);
+      v = new File_read::View(poff, psize, pbytes, cache, true);
+    }
 
-  File_read::View* v = new File_read::View(poff, psize, p);
   ins.first->second = v;
   return v;
 }
@@ -276,18 +301,18 @@ File_read::find_or_make_view(off_t start, off_t size)
 // mmap.
 
 const unsigned char*
-File_read::get_view(off_t start, off_t size)
+File_read::get_view(off_t start, off_t size, bool cache)
 {
   gold_assert(this->lock_count_ > 0);
-  File_read::View* pv = this->find_or_make_view(start, size);
+  File_read::View* pv = this->find_or_make_view(start, size, cache);
   return pv->data() + (start - pv->start());
 }
 
 File_view*
-File_read::get_lasting_view(off_t start, off_t size)
+File_read::get_lasting_view(off_t start, off_t size, bool cache)
 {
   gold_assert(this->lock_count_ > 0);
-  File_read::View* pv = this->find_or_make_view(start, size);
+  File_read::View* pv = this->find_or_make_view(start, size, cache);
   pv->lock();
   return new File_view(*this, pv, pv->data() + (start - pv->start()));
 }
@@ -301,7 +326,8 @@ File_read::clear_views(bool destroying)
        p != this->views_.end();
        ++p)
     {
-      if (!p->second->is_locked())
+      if (!p->second->is_locked()
+         && (destroying || !p->second->should_cache()))
        delete p->second;
       else
        {
@@ -314,7 +340,8 @@ File_read::clear_views(bool destroying)
   Saved_views::iterator p = this->saved_views_.begin();
   while (p != this->saved_views_.end())
     {
-      if (!(*p)->is_locked())
+      if (!(*p)->is_locked()
+         && (destroying || !(*p)->should_cache()))
        {
          delete *p;
          p = this->saved_views_.erase(p);