-// compressed_output.cc -- manage compressed output sections for gold
+// compressed_output.cc -- manage compressed debug sections for gold
-// Copyright 2007 Free Software Foundation, Inc.
+// Copyright 2007, 2008, 2010 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
#include <zlib.h>
#endif
-#include "compressed_output.h"
#include "parameters.h"
+#include "options.h"
+#include "compressed_output.h"
namespace gold
{
+#ifdef HAVE_ZLIB_H
+
// Compress UNCOMPRESSED_DATA of size UNCOMPRESSED_SIZE. Returns true
// if it successfully compressed, false if it failed for any reason
// (including not having zlib support in the library). If it returns
// true, it allocates memory for the compressed data using new, and
// sets *COMPRESSED_DATA and *COMPRESSED_SIZE to appropriate values.
-
-#ifdef HAVE_ZLIB_H
+// It also writes a header before COMPRESSED_DATA: 4 bytes saying
+// "ZLIB", and 8 bytes indicating the uncompressed size, in big-endian
+// order.
static bool
-zlib_compress(const char* uncompressed_data, unsigned long uncompressed_size,
- char** compressed_data, unsigned long* compressed_size)
+zlib_compress(const unsigned char* uncompressed_data,
+ unsigned long uncompressed_size,
+ unsigned char** compressed_data,
+ unsigned long* compressed_size)
{
+ const int header_size = 12;
*compressed_size = uncompressed_size + uncompressed_size / 1000 + 128;
- *compressed_data = new char[*compressed_size];
+ *compressed_data = new unsigned char[*compressed_size + header_size];
int compress_level;
- if (parameters->optimization_level() >= 1)
+ if (parameters->options().optimize() >= 1)
compress_level = 9;
else
compress_level = 1;
- int rc = compress2(reinterpret_cast<Bytef*>(*compressed_data),
+ int rc = compress2(reinterpret_cast<Bytef*>(*compressed_data) + header_size,
compressed_size,
reinterpret_cast<const Bytef*>(uncompressed_data),
uncompressed_size,
compress_level);
if (rc == Z_OK)
- return true;
+ {
+ memcpy(*compressed_data, "ZLIB", 4);
+ elfcpp::Swap_unaligned<64, true>::writeval(*compressed_data + 4,
+ uncompressed_size);
+ *compressed_size += header_size;
+ return true;
+ }
else
{
delete[] *compressed_data;
}
}
+// Decompress COMPRESSED_DATA of size COMPRESSED_SIZE, into a buffer
+// UNCOMPRESSED_DATA of size UNCOMPRESSED_SIZE. Returns TRUE if it
+// decompressed successfully, false if it failed. The buffer, of
+// appropriate size, is provided by the caller, and is typically part
+// of the memory-mapped output file.
+
+static bool
+zlib_decompress(const unsigned char* compressed_data,
+ unsigned long compressed_size,
+ unsigned char* uncompressed_data,
+ unsigned long uncompressed_size)
+{
+ z_stream strm;
+ int rc;
+
+ /* It is possible the section consists of several compressed
+ buffers concatenated together, so we uncompress in a loop. */
+ strm.zalloc = NULL;
+ strm.zfree = NULL;
+ strm.opaque = NULL;
+ strm.avail_in = compressed_size;
+ strm.next_in = const_cast<Bytef*>(compressed_data);
+ strm.avail_out = uncompressed_size;
+
+ rc = inflateInit(&strm);
+ while (strm.avail_in > 0)
+ {
+ if (rc != Z_OK)
+ return false;
+ strm.next_out = ((Bytef*) uncompressed_data
+ + (uncompressed_size - strm.avail_out));
+ rc = inflate(&strm, Z_FINISH);
+ if (rc != Z_STREAM_END)
+ return false;
+ rc = inflateReset(&strm);
+ }
+ rc = inflateEnd(&strm);
+ if (rc != Z_OK || strm.avail_out != 0)
+ return false;
+
+ return true;
+}
+
#else // !defined(HAVE_ZLIB_H)
static bool
-zlib_compress(const char*, unsigned long, char**, unsigned long*)
+zlib_compress(const unsigned char*, unsigned long,
+ unsigned char**, unsigned long*)
+{
+ return false;
+}
+
+static bool
+zlib_decompress(const unsigned char*, unsigned long,
+ unsigned char*, unsigned long)
{
return false;
}
#endif // !defined(HAVE_ZLIB_H)
-// After compressing an output section, we rename it from foo to
-// foo.zlib.nnnn, where nnnn is the uncompressed size of the section.
+// Read the compression header of a compressed debug section and return
+// the uncompressed size.
-static std::string
-zlib_compressed_suffix(unsigned long uncompressed_size)
+uint64_t
+get_uncompressed_size(const unsigned char* compressed_data,
+ section_size_type compressed_size)
{
- char size_string[64];
- snprintf(size_string, sizeof(size_string), "%lu", uncompressed_size);
- return std::string(".zlib.") + size_string;
+ const unsigned int zlib_header_size = 12;
+
+ /* Verify the compression header. Currently, we support only zlib
+ compression, so it should be "ZLIB" followed by the uncompressed
+ section size, 8 bytes in big-endian order. */
+ if (compressed_size >= zlib_header_size
+ && strncmp(reinterpret_cast<const char*>(compressed_data),
+ "ZLIB", 4) == 0)
+ return elfcpp::Swap_unaligned<64, true>::readval(compressed_data + 4);
+ return -1ULL;
}
-// Class Output_compressed_section_data.
-
-// Add an input section. In this case, we just keep track of the sections.
+// Decompress a compressed debug section directly into the output file.
bool
-Output_compressed_section_data::do_add_input_section(Relobj* obj,
- unsigned int shndx)
+decompress_input_section(const unsigned char* compressed_data,
+ unsigned long compressed_size,
+ unsigned char* uncompressed_data,
+ unsigned long uncompressed_size)
{
- this->objects_.push_back(Object_entry(obj, shndx));
- return true;
+ const unsigned int zlib_header_size = 12;
+
+ /* Verify the compression header. Currently, we support only zlib
+ compression, so it should be "ZLIB" followed by the uncompressed
+ section size, 8 bytes in big-endian order. */
+ if (compressed_size >= zlib_header_size
+ && strncmp(reinterpret_cast<const char*>(compressed_data),
+ "ZLIB", 4) == 0)
+ {
+ unsigned long uncompressed_size_check =
+ elfcpp::Swap_unaligned<64, true>::readval(compressed_data + 4);
+ gold_assert(uncompressed_size_check == uncompressed_size);
+ return zlib_decompress(compressed_data + zlib_header_size,
+ compressed_size - zlib_header_size,
+ uncompressed_data,
+ uncompressed_size);
+ }
+ return false;
}
+// Class Output_compressed_section.
+
// Set the final data size of a compressed section. This is where
// we actually compress the section data.
void
-Output_compressed_section_data::set_final_data_size()
+Output_compressed_section::set_final_data_size()
{
- // FIXME: assert that relocations have already been applied.
-
- off_t uncompressed_size = 0;
- for (std::vector<Object_entry>::iterator it = this->objects_.begin();
- it != this->objects_.end();
- ++it)
- {
- it->contents
- = it->object->section_contents(it->shndx, &it->length, false);
- uncompressed_size += it->length;
- }
+ off_t uncompressed_size = this->postprocessing_buffer_size();
// (Try to) compress the data.
unsigned long compressed_size;
- char* uncompressed_data = new char[uncompressed_size];
- off_t pos = 0;
- for (std::vector<Object_entry>::const_iterator it = this->objects_.begin();
- it != this->objects_.end();
- ++it)
- {
- memcpy(uncompressed_data + pos,
- reinterpret_cast<const char*>(it->contents),
- it->length);
- pos += it->length;
- }
+ unsigned char* uncompressed_data = this->postprocessing_buffer();
+
+ // At this point the contents of all regular input sections will
+ // have been copied into the postprocessing buffer, and relocations
+ // will have been applied. Now we need to copy in the contents of
+ // anything other than a regular input section.
+ this->write_to_postprocessing_buffer();
bool success = false;
- if (options_.zlib_compress_debug_sections())
+ if (strcmp(this->options_->compress_debug_sections(), "zlib") == 0)
success = zlib_compress(uncompressed_data, uncompressed_size,
&this->data_, &compressed_size);
if (success)
{
- delete[] uncompressed_data;
+ // This converts .debug_foo to .zdebug_foo
+ this->new_section_name_ = std::string(".z") + (this->name() + 1);
+ this->set_name(this->new_section_name_.c_str());
this->set_data_size(compressed_size);
- this->new_section_name_ = zlib_compressed_suffix(uncompressed_size);
}
else
{
- gold_warning(_("Not compressing section data: zlib error"));
+ gold_warning(_("not compressing section data: zlib error"));
gold_assert(this->data_ == NULL);
- this->data_ = uncompressed_data;
this->set_data_size(uncompressed_size);
}
}
-// Change the name of the output section to reflect it's compressed.
-// The layout routines call into this right before finalizing the
-// shstrtab.
-
-const char*
-Output_compressed_section_data::do_modified_output_section_name(
- const char* name)
-{
- // This mean we never compressed the data.
- if (this->new_section_name_.empty())
- return NULL;
- this->new_section_name_ = std::string(name) + this->new_section_name_;
- return this->new_section_name_.c_str();
-}
-
// Write out a compressed section. If we couldn't compress, we just
// write it out as normal, uncompressed data.
void
-Output_compressed_section_data::do_write(Output_file* of)
+Output_compressed_section::do_write(Output_file* of)
{
- unsigned char* uview = of->get_output_view(this->offset(),
- this->data_size());
- char* view = reinterpret_cast<char*>(uview);
- memcpy(view, this->data_, this->data_size());
- of->write_output_view(this->offset(), this->data_size(), uview);
-}
-
-// Class Output_compressed_string.
-
-// Add an input section. We don't do anything special here.
-
-template<typename Char_type>
-bool
-Output_compressed_string<Char_type>::do_add_input_section(Relobj* object,
- unsigned int shndx)
-{
- return Output_merge_string<Char_type>::do_add_input_section(object, shndx);
-}
-
-// Set the final data size of a compressed section. This is where
-// we actually compress the section data.
-
-template<typename Char_type>
-void
-Output_compressed_string<Char_type>::set_final_data_size()
-{
- // First let the superclass finalize all its data, then write it to
- // a buffer.
- unsigned long uncompressed_size = this->finalize_merged_data();
- char* uncompressed_data = new char[uncompressed_size];
- this->stringpool_to_buffer(uncompressed_data, uncompressed_size);
-
- // (Try to) compress the data.
- unsigned long compressed_size;
- if (options_.zlib_compress_debug_sections()
- && zlib_compress(uncompressed_data, uncompressed_size,
- &this->compressed_data_, &compressed_size))
- {
- this->set_data_size(compressed_size);
- // Save some memory.
- this->clear_stringpool();
- // We will be renaming the section to name.zlib.uncompressed_size.
- this->new_section_name_ = zlib_compressed_suffix(uncompressed_size);
- }
- else
- {
- this->compressed_data_ = NULL;
- this->set_data_size(uncompressed_size);
- }
-
- delete[] uncompressed_data;
-}
-
-// Change the name of the output section to reflect it's compressed.
-// The layout routines call into this right before finalizing the
-// shstrtab.
-
-template<typename Char_type>
-const char*
-Output_compressed_string<Char_type>::do_modified_output_section_name(
- const char* name)
-{
- // This mean we never compressed the data
- if (this->new_section_name_.empty())
- return NULL;
- this->new_section_name_ = std::string(name) + this->new_section_name_;
- return this->new_section_name_.c_str();
-}
-
-// Write out a compressed string section. If we couldn't compress,
-// we just write out the normal string section.
-
-template<typename Char_type>
-void
-Output_compressed_string<Char_type>::do_write(Output_file* of)
-{
- if (this->compressed_data_ == NULL)
- Output_merge_string<Char_type>::do_write(of);
+ off_t offset = this->offset();
+ off_t data_size = this->data_size();
+ unsigned char* view = of->get_output_view(offset, data_size);
+ if (this->data_ == NULL)
+ memcpy(view, this->postprocessing_buffer(), data_size);
else
- {
- unsigned char* uview = of->get_output_view(this->offset(),
- this->data_size());
- char* view = reinterpret_cast<char*>(uview);
- memcpy(view, this->compressed_data_, this->data_size());
- of->write_output_view(this->offset(), this->data_size(), uview);
- }
+ memcpy(view, this->data_, data_size);
+ of->write_output_view(offset, data_size, view);
}
-// Instantiate the templates we need.
-
-template
-class Output_compressed_string<char>;
-
-template
-class Output_compressed_string<uint16_t>;
-
-template
-class Output_compressed_string<uint32_t>;
-
} // End namespace gold.
projects / deliverable / binutils-gdb.git / blobdiff