Full support for --sysroot.
[binutils-gdb.git] / gold / fileread.cc
index a39d530ab8753ed65b567a3405e0e9b32eb5da63..1bbd8412a8109cf1e6c051dd0311a50d133b25b9 100644 (file)
@@ -26,6 +26,8 @@
 #include <cerrno>
 #include <fcntl.h>
 #include <unistd.h>
+#include <sys/mman.h>
+#include "filenames.h"
 
 #include "options.h"
 #include "dirsearch.h"
@@ -39,7 +41,14 @@ 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
@@ -89,8 +98,23 @@ File_read::open(const std::string& name)
              && this->descriptor_ < 0
              && this->name_.empty());
   this->name_ = name;
+
   this->descriptor_ = ::open(this->name_.c_str(), O_RDONLY);
+
+  if (this->descriptor_ >= 0)
+    {
+      struct stat s;
+      if (::fstat(this->descriptor_, &s) < 0)
+       {
+         fprintf(stderr, _("%s: %s: fstat failed: %s"), program_name,
+                 this->name_.c_str(), strerror(errno));
+         gold_exit(false);
+       }
+      this->size_ = s.st_size;
+    }
+
   ++this->lock_count_;
+
   return this->descriptor_ >= 0;
 }
 
@@ -98,14 +122,14 @@ File_read::open(const std::string& name)
 
 bool
 File_read::open(const std::string& name, const unsigned char* contents,
-               off_t contents_size)
+               off_t size)
 {
   gold_assert(this->lock_count_ == 0
              && this->descriptor_ < 0
              && this->name_.empty());
   this->name_ = name;
   this->contents_ = contents;
-  this->contents_size_ = contents_size;
+  this->size_ = size;
   ++this->lock_count_;
   return true;
 }
@@ -121,6 +145,8 @@ File_read::unlock()
 {
   gold_assert(this->lock_count_ > 0);
   --this->lock_count_;
+  if (this->lock_count_ == 0)
+    this->clear_views(false);
 }
 
 bool
@@ -144,62 +170,45 @@ File_read::find_view(off_t start, off_t size)
   return p->second;
 }
 
-// Read data from the file.  Return the number of bytes read.  If
-// PBYTES is not NULL, store the number of bytes in *PBYTES, otherwise
-// require that we read exactly the number of bytes requested.
+// Read SIZE bytes from the file starting at offset START.  Read into
+// the buffer at P.
 
-off_t
-File_read::do_read(off_t start, off_t size, void* p, off_t* pbytes)
+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)
+  if (this->contents_ != NULL)
     {
-      int o = this->descriptor_;
-
-      if (lseek(o, start, SEEK_SET) < 0)
+      bytes = this->size_ - start;
+      if (bytes >= size)
        {
-         fprintf(stderr, _("%s: %s: lseek to %lld failed: %s"),
-                 program_name, this->filename().c_str(),
-                 static_cast<long long>(start),
-                 strerror(errno));
-         gold_exit(false);
+         memcpy(p, this->contents_ + start, size);
+         return;
        }
+    }
+  else
+    {
+      bytes = ::pread(this->descriptor_, p, size, start);
+      if (bytes == size)
+       return;
 
-      bytes = ::read(o, p, size);
       if (bytes < 0)
        {
-         fprintf(stderr, _("%s: %s: read failed: %s\n"),
+         fprintf(stderr, _("%s: %s: pread failed: %s\n"),
                  program_name, this->filename().c_str(), strerror(errno));
          gold_exit(false);
        }
     }
-  else
-    {
-      bytes = this->contents_size_ - start;
-      if (bytes < 0)
-       bytes = 0;
-      else if (bytes > size)
-       bytes = size;
-      memcpy(p, this->contents_ + start, bytes);
-    }
 
-  if (pbytes != NULL)
-    *pbytes = bytes;
-  else 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);
-    }
-
-  return bytes;
+  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.
@@ -216,30 +225,13 @@ File_read::read(off_t start, off_t size, void* p)
       return;
     }
 
-  this->do_read(start, size, p, NULL);
-}
-
-void
-File_read::read_up_to(off_t start, off_t size, void* p, off_t* pbytes)
-{
-  gold_assert(this->lock_count_ > 0);
-
-  File_read::View* pv = this->find_view(start, size);
-  if (pv != NULL)
-    {
-      memcpy(p, pv->data() + (start - pv->start()), size);
-      if (pbytes != NULL)
-       *pbytes = size;
-      return;
-    }
-
-  this->do_read(start, size, p, pbytes);
+  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, off_t* pbytes)
+File_read::find_or_make_view(off_t start, off_t size, bool cache)
 {
   gold_assert(this->lock_count_ > 0);
 
@@ -255,8 +247,8 @@ File_read::find_or_make_view(off_t start, off_t size, off_t* pbytes)
       File_read::View* v = ins.first->second;
       if (v->size() - (start - v->start()) >= size)
        {
-         if (pbytes != NULL)
-           *pbytes = size;
+         if (cache)
+           v->set_cache();
          return v;
        }
 
@@ -264,38 +256,45 @@ File_read::find_or_make_view(off_t start, off_t size, off_t* pbytes)
       this->saved_views_.push_back(v);
     }
 
-  // We need to read data from the file.
+  // We need to read data from the file.  We read full pages for
+  // greater efficiency on small files.
 
   off_t psize = File_read::pages(size + (start - poff));
-  unsigned char* p = new unsigned char[psize];
 
-  off_t got_bytes;
-  off_t bytes = this->do_read(poff, psize, p, &got_bytes);
+  if (poff + psize >= this->size_)
+    {
+      psize = this->size_ - poff;
+      gold_assert(psize >= size);
+    }
 
-  File_read::View* v = new File_read::View(poff, bytes, p);
+  File_read::View* v;
 
-  ins.first->second = v;
-
-  if (bytes - (start - poff) >= size)
+  if (this->contents_ != NULL)
     {
-      if (pbytes != NULL)
-       *pbytes = size;
-      return v;
+      unsigned char* p = new unsigned char[psize];
+      this->do_read(poff, psize, p);
+      v = new File_read::View(poff, psize, p, cache, false);
     }
-
-  if (pbytes != NULL)
+  else
     {
-      *pbytes = bytes - (start - poff);
-      return v;
+      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);
     }
 
-  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 - (start - poff)),
-         static_cast<long long>(size),
-         static_cast<long long>(start));
-  gold_exit(false);
+  ins.first->second = v;
+  return v;
 }
 
 // This implementation of get_view just reads into a memory buffer,
@@ -303,26 +302,18 @@ File_read::find_or_make_view(off_t start, off_t size, off_t* pbytes)
 // mmap.
 
 const unsigned char*
-File_read::get_view(off_t start, off_t size)
-{
-  gold_assert(this->lock_count_ > 0);
-  File_read::View* pv = this->find_or_make_view(start, size, NULL);
-  return pv->data() + (start - pv->start());
-}
-
-const unsigned char*
-File_read::get_view_and_size(off_t start, off_t size, off_t* pbytes)
+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, pbytes);
+  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, NULL);
+  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()));
 }
@@ -336,7 +327,8 @@ 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
        {
@@ -349,7 +341,8 @@ 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);
@@ -379,21 +372,38 @@ Input_file::Input_file(const char* name, const unsigned char* contents,
   : file_()
 {
   this->input_argument_ =
-    new Input_file_argument(name, false, Position_dependent_options());
+    new Input_file_argument(name, false, "", Position_dependent_options());
   bool ok = file_.open(name, contents, size);
   gold_assert(ok);
 }
 
 // Open the file.
 
+// If the filename is not absolute, we assume it is in the current
+// directory *except* when:
+//    A) input_argument_->is_lib() is true; or
+//    B) input_argument_->extra_search_path() is not empty.
+// In both cases, we look in extra_search_path + library_path to find
+// the file location, rather than the current directory.
+
 void
 Input_file::open(const General_options& options, const Dirsearch& dirpath)
 {
   std::string name;
-  if (!this->input_argument_->is_lib())
+
+  // Case 1: name is an absolute file, just try to open it
+  // Case 2: name is relative but is_lib is false and extra_search_path
+  //         is empty
+  if (IS_ABSOLUTE_PATH (this->input_argument_->name())
+      || (!this->input_argument_->is_lib()
+         && this->input_argument_->extra_search_path() == NULL))
     name = this->input_argument_->name();
-  else
+
+  // Case 3: is_lib is true
+  else if (this->input_argument_->is_lib())
     {
+      // We don't yet support extra_search_path with -l.
+      gold_assert(this->input_argument_->extra_search_path() == NULL);
       std::string n1("lib");
       n1 += this->input_argument_->name();
       std::string n2;
@@ -404,15 +414,41 @@ Input_file::open(const General_options& options, const Dirsearch& dirpath)
          n2 = n1 + ".a";
          n1 += ".so";
        }
-      name = dirpath.find(n1, n2);
+      name = dirpath.find(n1, n2, &this->is_in_sysroot_);
       if (name.empty())
        {
-         fprintf(stderr, _("%s: cannot find %s\n"), program_name,
+         fprintf(stderr, _("%s: cannot find -l%s\n"), program_name,
                  this->input_argument_->name());
          gold_exit(false);
        }
     }
 
+  // Case 4: extra_search_path is not empty
+  else
+    {
+      gold_assert(this->input_argument_->extra_search_path() != NULL);
+
+      // First, check extra_search_path.
+      name = this->input_argument_->extra_search_path();
+      if (!IS_DIR_SEPARATOR (name[name.length() - 1]))
+        name += '/';
+      name += this->input_argument_->name();
+      struct stat dummy_stat;
+      if (::stat(name.c_str(), &dummy_stat) < 0)
+        {
+          // extra_search_path failed, so check the normal search-path.
+          name = dirpath.find(this->input_argument_->name(), "",
+                             &this->is_in_sysroot_);
+          if (name.empty())
+            {
+              fprintf(stderr, _("%s: cannot find %s\n"), program_name,
+                      this->input_argument_->name());
+              gold_exit(false);
+            }
+        }
+    }
+
+  // Now that we've figured out where the file lives, try to open it.
   if (!this->file_.open(name))
     {
       fprintf(stderr, _("%s: cannot open %s: %s\n"), program_name,