X-Git-Url: http://git.sourceforge.jp/view?p=pf3gnuchains%2Fgcc-fork.git;a=blobdiff_plain;f=gcc%2Fgo%2Fgo-backend.c;h=5dab2f1864c95f7f2a63982dbef6b0b9006a7e38;hp=60a97db7df4e295ce7f391d33c67d2897773bed1;hb=927a01eba66c97c810b74e48669832863c8b846d;hpb=f3231e7d248b775b337f8fa56d81b296c03dfd77

diff --git a/gcc/go/go-backend.c b/gcc/go/go-backend.c
index 60a97db7df4..5dab2f1864c 100644
--- a/gcc/go/go-backend.c
+++ b/gcc/go/go-backend.c
@@ -1,5 +1,5 @@
 /* go-backend.c -- Go frontend interface to gcc backend.
-   Copyright (C) 2010, 2011 Free Software Foundation, Inc.
+   Copyright (C) 2010, 2011, 2012 Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -20,25 +20,33 @@ along with GCC; see the file COPYING3.  If not see
 #include "config.h"
 #include "system.h"
 #include "coretypes.h"
+#include "simple-object.h"
 #include "tm.h"
 #include "rtl.h"
 #include "tree.h"
 #include "tm_p.h"
+#include "intl.h"
 #include "output.h"
 #include "target.h"
+#include "common/common-target.h"
 
 #include "go-c.h"
 
-/* This file holds all the cases where the Go frontend needs
-   information from gcc's backend.  */
+/* The segment name we pass to simple_object_start_read to find Go
+   export data.  */
 
-/* Return the alignment in bytes of a value of type T.  */
+#ifndef GO_EXPORT_SEGMENT_NAME
+#define GO_EXPORT_SEGMENT_NAME "__GNU_GO"
+#endif
 
-unsigned int
-go_type_alignment (tree t)
-{
-  return TYPE_ALIGN_UNIT (t);
-}
+/* The section name we use when reading and writing export data.  */
+
+#ifndef GO_EXPORT_SECTION_NAME
+#define GO_EXPORT_SECTION_NAME ".go_export"
+#endif
+
+/* This file holds all the cases where the Go frontend needs
+   information from gcc's backend.  */
 
 /* Return the alignment in bytes of a struct field of type T.  */
 
@@ -94,7 +102,7 @@ go_imported_unsafe (void)
 }
 
 /* This is called by the Go frontend proper to add data to the
-   .go_export section.  */
+   section containing Go export data.  */
 
 void
 go_write_export_data (const char *bytes, unsigned int size)
@@ -103,10 +111,88 @@ go_write_export_data (const char *bytes, unsigned int size)
 
   if (sec == NULL)
     {
-      gcc_assert (targetm.have_named_sections);
-      sec = get_section (".go_export", SECTION_DEBUG, NULL);
+      gcc_assert (targetm_common.have_named_sections);
+      sec = get_section (GO_EXPORT_SECTION_NAME, SECTION_DEBUG, NULL);
     }
 
   switch_to_section (sec);
   assemble_string (bytes, size);
 }
+
+/* The go_read_export_data function is called by the Go frontend
+   proper to read Go export data from an object file.  FD is a file
+   descriptor open for reading.  OFFSET is the offset within the file
+   where the object file starts; this will be 0 except when reading an
+   archive.  On success this returns NULL and sets *PBUF to a buffer
+   allocated using malloc, of size *PLEN, holding the export data.  If
+   the data is not found, this returns NULL and sets *PBUF to NULL and
+   *PLEN to 0.  If some error occurs, this returns an error message
+   and sets *PERR to an errno value or 0 if there is no relevant
+   errno.  */
+
+const char *
+go_read_export_data (int fd, off_t offset, char **pbuf, size_t *plen,
+		     int *perr)
+{
+  simple_object_read *sobj;
+  const char *errmsg;
+  off_t sec_offset;
+  off_t sec_length;
+  int found;
+  char *buf;
+  ssize_t c;
+
+  *pbuf = NULL;
+  *plen = 0;
+
+  sobj = simple_object_start_read (fd, offset, GO_EXPORT_SEGMENT_NAME,
+				   &errmsg, perr);
+  if (sobj == NULL)
+    {
+      /* If we get an error here, just pretend that we didn't find any
+	 export data.  This is the right thing to do if the error is
+	 that the file was not recognized as an object file.  This
+	 will ignore file I/O errors, but it's not too big a deal
+	 because we will wind up giving some other error later.  */
+      return NULL;
+    }
+
+  found = simple_object_find_section (sobj, GO_EXPORT_SECTION_NAME,
+				      &sec_offset, &sec_length,
+				      &errmsg, perr);
+  simple_object_release_read (sobj);
+  if (!found)
+    return errmsg;
+
+  if (lseek (fd, offset + sec_offset, SEEK_SET) < 0)
+    {
+      *perr = errno;
+      return _("lseek failed while reading export data");
+    }
+
+  buf = XNEWVEC (char, sec_length);
+  if (buf == NULL)
+    {
+      *perr = errno;
+      return _("memory allocation failed while reading export data");
+    }
+
+  c = read (fd, buf, sec_length);
+  if (c < 0)
+    {
+      *perr = errno;
+      free (buf);
+      return _("read failed while reading export data");
+    }
+
+  if (c < sec_length)
+    {
+      free (buf);
+      return _("short read while reading export data");
+    }
+
+  *pbuf = buf;
+  *plen = sec_length;
+
+  return NULL;
+}