text: /*
   * File elf.c - processing of ELF files
   *
   * Copyright (C) 1996, Eric Youngdale.
   *		 1999-2007 Eric Pouech
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
   */
  
  #include <assert.h>
  #include <stdio.h>
  #include <stdlib.h>
  
  #include "dbghelp_private.h"
  #include "image_private.h"
  #include "winternl.h"
  
  #include "wine/debug.h"
  #include "wine/heap.h"
  
  #define ELF_INFO_DEBUG_HEADER   0x0001
  #define ELF_INFO_MODULE         0x0002
  #define ELF_INFO_NAME           0x0004
  
  WINE_DEFAULT_DEBUG_CHANNEL(dbghelp);
  
  struct elf_info
  {
      unsigned                    flags;          /* IN  one (or several) of the ELF_INFO constants */
      DWORD_PTR                   dbg_hdr_addr;   /* OUT address of debug header (if ELF_INFO_DEBUG_HEADER is set) */
      struct module*              module;         /* OUT loaded module (if ELF_INFO_MODULE is set) */
      const WCHAR*                module_name;    /* OUT found module name (if ELF_INFO_NAME is set) */
  };
  
  struct elf_sym32
  {
      UINT32                      st_name;   /* Symbol name (string tbl index) */
      UINT32                      st_value;  /* Symbol value */
      UINT32                      st_size;   /* Symbol size */
      UINT8                       st_info;   /* Symbol type and binding */
      UINT8                       st_other;  /* Symbol visibility */
      UINT16                      st_shndx;  /* Section index */
  };
  
  struct elf_sym
  {
      UINT32                      st_name;   /* Symbol name (string tbl index) */
      UINT8                       st_info;   /* Symbol type and binding */
      UINT8                       st_other;  /* Symbol visibility */
      UINT16                      st_shndx;  /* Section index */
      UINT64                      st_value;  /* Symbol value */
      UINT64                      st_size;   /* Symbol size */
  };
  
  struct symtab_elt
  {
      struct hash_table_elt       ht_elt;
      struct elf_sym              sym;
      struct symt_compiland*      compiland;
      unsigned                    used;
  };
  
  struct elf_thunk_area
  {
      const char*                 symname;
      THUNK_ORDINAL               ordinal;
      ULONG_PTR                   rva_start;
      ULONG_PTR                   rva_end;
  };
  
  struct elf_module_info
  {
      ULONG_PTR                   elf_addr;
      unsigned short	        elf_mark : 1,
                                  elf_loader : 1;
      struct image_file_map       file_map;
  };
  
  /* Legal values for sh_type (section type).  */
  #define ELF_SHT_NULL            0    /* Section header table entry unused */
  #define ELF_SHT_PROGBITS        1    /* Program data */
  #define ELF_SHT_SYMTAB          2    /* Symbol table */
  #define ELF_SHT_STRTAB          3    /* String table */
  #define ELF_SHT_RELA            4    /* Relocation entries with addends */
  #define ELF_SHT_HASH            5    /* Symbol hash table */
  #define ELF_SHT_DYNAMIC         6    /* Dynamic linking information */
  #define ELF_SHT_NOTE            7    /* Notes */
  #define ELF_SHT_NOBITS          8    /* Program space with no data (bss) */
  #define ELF_SHT_REL             9    /* Relocation entries, no addends */
  #define ELF_SHT_SHLIB          10    /* Reserved */
  #define ELF_SHT_DYNSYM         11    /* Dynamic linker symbol table */
  #define ELF_SHT_INIT_ARRAY     14    /* Array of constructors */
  #define ELF_SHT_FINI_ARRAY     15    /* Array of destructors */
  #define ELF_SHT_PREINIT_ARRAY  16    /* Array of pre-constructors */
  #define ELF_SHT_GROUP          17    /* Section group */
  #define ELF_SHT_SYMTAB_SHNDX   18    /* Extended section indices */
  #define ELF_SHT_NUM            19    /* Number of defined types.  */
  
  /* Legal values for ST_TYPE subfield of st_info (symbol type).  */
  #define ELF_STT_NOTYPE          0    /* Symbol type is unspecified */
  #define ELF_STT_OBJECT          1    /* Symbol is a data object */
  #define ELF_STT_FUNC            2    /* Symbol is a code object */
  #define ELF_STT_SECTION         3    /* Symbol associated with a section */
  #define ELF_STT_FILE            4    /* Symbol's name is file name */
  
  #define ELF_PT_LOAD             1    /* Loadable program segment */
  
  #define ELF_DT_DEBUG           21    /* For debugging; unspecified */
  
  #define ELF_AT_SYSINFO_EHDR    33
  
  /******************************************************************
   *		elf_map_section
   *
   * Maps a single section into memory from an ELF file
   */
  static const char* elf_map_section(struct image_section_map* ism)
  {
      struct elf_file_map*        fmap = &ism->fmap->u.elf;
      SIZE_T ofst, size;
      HANDLE mapping;
  
      assert(ism->fmap->modtype == DMT_ELF);
      if (ism->sidx < 0 || ism->sidx >= ism->fmap->u.elf.elfhdr.e_shnum ||
          fmap->sect[ism->sidx].shdr.sh_type == ELF_SHT_NOBITS)
          return IMAGE_NO_MAP;
  
      if (fmap->target_copy)
      {
          return fmap->target_copy + fmap->sect[ism->sidx].shdr.sh_offset;
      }
  
      /* align required information on allocation granularity */
      ofst = fmap->sect[ism->sidx].shdr.sh_offset & ~(sysinfo.dwAllocationGranularity - 1);
      size = fmap->sect[ism->sidx].shdr.sh_offset + fmap->sect[ism->sidx].shdr.sh_size - ofst;
      if (!(mapping = CreateFileMappingW(fmap->handle, NULL, PAGE_READONLY, 0, ofst + size, NULL)))
      {
          ERR("map creation %p failed %u offset %lu %lu size %lu\n", fmap->handle, GetLastError(), ofst, ofst % 4096, size);
          return IMAGE_NO_MAP;
      }
      fmap->sect[ism->sidx].mapped = MapViewOfFile(mapping, FILE_MAP_READ, 0, ofst, size);
      CloseHandle(mapping);
      if (!fmap->sect[ism->sidx].mapped)
      {
          ERR("map %p failed %u offset %lu %lu size %lu\n", fmap->handle, GetLastError(), ofst, ofst % 4096, size);
          return IMAGE_NO_MAP;
      }
      return fmap->sect[ism->sidx].mapped + (fmap->sect[ism->sidx].shdr.sh_offset & (sysinfo.dwAllocationGranularity - 1));
  }
  
  /******************************************************************
   *		elf_find_section
   *
   * Finds a section by name (and type) into memory from an ELF file
   * or its alternate if any
   */
  static BOOL elf_find_section(struct image_file_map* _fmap, const char* name, struct image_section_map* ism)
  {
      struct elf_file_map*        fmap = &_fmap->u.elf;
      unsigned i;
  
      if (fmap->shstrtab == IMAGE_NO_MAP)
      {
          struct image_section_map  hdr_ism = {_fmap, fmap->elfhdr.e_shstrndx};
          if ((fmap->shstrtab = elf_map_section(&hdr_ism)) == IMAGE_NO_MAP) return FALSE;
      }
      for (i = 0; i < fmap->elfhdr.e_shnum; i++)
      {
          if (strcmp(fmap->shstrtab + fmap->sect[i].shdr.sh_name, name) == 0)
          {
              ism->fmap = _fmap;
              ism->sidx = i;
              return TRUE;
          }
      }
      return FALSE;
  }
  
  static BOOL elf_find_section_type(struct image_file_map* _fmap, const char* name, unsigned sht, struct image_section_map* ism)
  {
      struct elf_file_map*        fmap;
      unsigned i;
  
      while (_fmap)
      {
          if (_fmap->modtype != DMT_ELF) break;
          fmap = &_fmap->u.elf;
          if (fmap->shstrtab == IMAGE_NO_MAP)
          {
              struct image_section_map  hdr_ism = {_fmap, fmap->elfhdr.e_shstrndx};
              if ((fmap->shstrtab = elf_map_section(&hdr_ism)) == IMAGE_NO_MAP) break;
          }
          for (i = 0; i < fmap->elfhdr.e_shnum; i++)
          {
              if (strcmp(fmap->shstrtab + fmap->sect[i].shdr.sh_name, name) == 0 && sht == fmap->sect[i].shdr.sh_type)
              {
                  ism->fmap = _fmap;
                  ism->sidx = i;
                  return TRUE;
              }
          }
          _fmap = _fmap->alternate;
      }
      ism->fmap = NULL;
      ism->sidx = -1;
      return FALSE;
  }
  
  /******************************************************************
   *		elf_unmap_section
   *
   * Unmaps a single section from memory
   */
  static void elf_unmap_section(struct image_section_map* ism)
  {
      struct elf_file_map*        fmap = &ism->fmap->u.elf;
  
      if (ism->sidx >= 0 && ism->sidx < fmap->elfhdr.e_shnum && !fmap->target_copy &&
          fmap->sect[ism->sidx].mapped)
      {
          if (!UnmapViewOfFile(fmap->sect[ism->sidx].mapped))
              WARN("Couldn't unmap the section\n");
          fmap->sect[ism->sidx].mapped = NULL;
      }
  }
  
  static void elf_end_find(struct image_file_map* fmap)
  {
      struct image_section_map      ism;
  
      while (fmap && fmap->modtype == DMT_ELF)
      {
          ism.fmap = fmap;
          ism.sidx = fmap->u.elf.elfhdr.e_shstrndx;
          elf_unmap_section(&ism);
          fmap->u.elf.shstrtab = IMAGE_NO_MAP;
          fmap = fmap->alternate;
      }
  }
  
  /******************************************************************
   *		elf_get_map_rva
   *
   * Get the RVA of an ELF section
   */
  static DWORD_PTR elf_get_map_rva(const struct image_section_map* ism)
  {
      if (ism->sidx < 0 || ism->sidx >= ism->fmap->u.elf.elfhdr.e_shnum)
          return 0;
      return ism->fmap->u.elf.sect[ism->sidx].shdr.sh_addr - ism->fmap->u.elf.elf_start;
  }
  
  /******************************************************************
   *		elf_get_map_size
   *
   * Get the size of an ELF section
   */
  static unsigned elf_get_map_size(const struct image_section_map* ism)
  {
      if (ism->sidx < 0 || ism->sidx >= ism->fmap->u.elf.elfhdr.e_shnum)
          return 0;
      return ism->fmap->u.elf.sect[ism->sidx].shdr.sh_size;
  }
  
  /******************************************************************
   *		elf_unmap_file
   *
   * Unmaps an ELF file from memory (previously mapped with elf_map_file)
   */
  static void elf_unmap_file(struct image_file_map* fmap)
  {
      if (fmap->u.elf.handle != INVALID_HANDLE_VALUE)
      {
          struct image_section_map  ism;
          ism.fmap = fmap;
          for (ism.sidx = 0; ism.sidx < fmap->u.elf.elfhdr.e_shnum; ism.sidx++)
          {
              elf_unmap_section(&ism);
          }
          HeapFree(GetProcessHeap(), 0, fmap->u.elf.sect);
          CloseHandle(fmap->u.elf.handle);
      }
      HeapFree(GetProcessHeap(), 0, fmap->u.elf.target_copy);
  }
  
  static const struct image_file_map_ops elf_file_map_ops =
  {
      elf_map_section,
      elf_unmap_section,
      elf_find_section,
      elf_get_map_rva,
      elf_get_map_size,
      elf_unmap_file,
  };
  
  static inline void elf_reset_file_map(struct image_file_map* fmap)
  {
      fmap->ops = &elf_file_map_ops;
      fmap->alternate = NULL;
      fmap->u.elf.handle = INVALID_HANDLE_VALUE;
      fmap->u.elf.shstrtab = IMAGE_NO_MAP;
      fmap->u.elf.target_copy = NULL;
  }
  
  struct elf_map_file_data
  {
      enum {from_file, from_process, from_handle}      kind;
      union
      {
          struct
          {
              const WCHAR* filename;
          } file;
          struct
          {
              HANDLE      handle;
              void*       load_addr;
          } process;
          HANDLE handle;
      } u;
  };
  
  static BOOL elf_map_file_read(struct image_file_map* fmap, struct elf_map_file_data* emfd,
                                void* buf, size_t len, size_t off)
  {
      LARGE_INTEGER li;
      DWORD bytes_read;
      SIZE_T dw;
  
      switch (emfd->kind)
      {
      case from_file:
      case from_handle:
          li.QuadPart = off;
          if (!SetFilePointerEx(fmap->u.elf.handle, li, NULL, FILE_BEGIN)) return FALSE;
          return ReadFile(fmap->u.elf.handle, buf, len, &bytes_read, NULL);
      case from_process:
          return ReadProcessMemory(emfd->u.process.handle,
                                   (void*)((ULONG_PTR)emfd->u.process.load_addr + (ULONG_PTR)off),
                                   buf, len, &dw) && dw == len;
      default:
          assert(0);
          return FALSE;
      }
  }
  
  static BOOL elf_map_shdr(struct elf_map_file_data* emfd, struct image_file_map* fmap, unsigned int i)
  {
      if (fmap->addr_size == 32)
      {
          struct
          {
              UINT32  sh_name;       /* Section name (string tbl index) */
              UINT32  sh_type;       /* Section type */
              UINT32  sh_flags;      /* Section flags */
              UINT32  sh_addr;       /* Section virtual addr at execution */
              UINT32  sh_offset;     /* Section file offset */
              UINT32  sh_size;       /* Section size in bytes */
              UINT32  sh_link;       /* Link to another section */
              UINT32  sh_info;       /* Additional section information */
              UINT32  sh_addralign;  /* Section alignment */
              UINT32  sh_entsize;    /* Entry size if section holds table */
          } shdr32;
  
          if (!elf_map_file_read(fmap, emfd, &shdr32, sizeof(shdr32),
                                 fmap->u.elf.elfhdr.e_shoff + i * sizeof(shdr32)))
              return FALSE;
  
          fmap->u.elf.sect[i].shdr.sh_name      = shdr32.sh_name;
          fmap->u.elf.sect[i].shdr.sh_type      = shdr32.sh_type;
          fmap->u.elf.sect[i].shdr.sh_flags     = shdr32.sh_flags;
          fmap->u.elf.sect[i].shdr.sh_addr      = shdr32.sh_addr;
          fmap->u.elf.sect[i].shdr.sh_offset    = shdr32.sh_offset;
          fmap->u.elf.sect[i].shdr.sh_size      = shdr32.sh_size;
          fmap->u.elf.sect[i].shdr.sh_link      = shdr32.sh_link;
          fmap->u.elf.sect[i].shdr.sh_info      = shdr32.sh_info;
          fmap->u.elf.sect[i].shdr.sh_addralign = shdr32.sh_addralign;
          fmap->u.elf.sect[i].shdr.sh_entsize   = shdr32.sh_entsize;
      }
      else
      {
          if (!elf_map_file_read(fmap, emfd, &fmap->u.elf.sect[i].shdr, sizeof(fmap->u.elf.sect[i].shdr),
                                 fmap->u.elf.elfhdr.e_shoff + i * sizeof(fmap->u.elf.sect[i].shdr)))
              return FALSE;
      }
      return TRUE;
  }
  
  /******************************************************************
   *		elf_map_file
   *
   * Maps an ELF file into memory (and checks it's a real ELF file)
   */
  static BOOL elf_map_file(struct elf_map_file_data* emfd, struct image_file_map* fmap)
  {
      unsigned int        i;
      size_t              tmp, page_mask = sysinfo.dwPageSize - 1;
      WCHAR              *dos_path;
      unsigned char e_ident[ARRAY_SIZE(fmap->u.elf.elfhdr.e_ident)];
  
      elf_reset_file_map(fmap);
  
      fmap->modtype = DMT_ELF;
      fmap->u.elf.handle = INVALID_HANDLE_VALUE;
      fmap->u.elf.target_copy = NULL;
  
      switch (emfd->kind)
      {
      case from_file:
          if (!(dos_path = get_dos_file_name(emfd->u.file.filename))) return FALSE;
          fmap->u.elf.handle = CreateFileW(dos_path, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL);
          heap_free(dos_path);
          if (fmap->u.elf.handle == INVALID_HANDLE_VALUE) return FALSE;
          break;
      case from_handle:
          if (!DuplicateHandle(GetCurrentProcess(), emfd->u.handle, GetCurrentProcess(), &fmap->u.elf.handle, GENERIC_READ, FALSE, 0))
              return FALSE;
          break;
      case from_process:
          break;
      }
  
      if (!elf_map_file_read(fmap, emfd, e_ident, sizeof(e_ident), 0))
          return FALSE;
  
      /* and check for an ELF header */
      if (memcmp(e_ident, "\177ELF", 4))
          return FALSE;
  
      fmap->addr_size = e_ident[4] == 2 /* ELFCLASS64 */ ? 64 : 32;
  
      if (fmap->addr_size == 32)
      {
          struct
          {
              UINT8   e_ident[16];  /* Magic number and other info */
              UINT16  e_type;       /* Object file type */
              UINT16  e_machine;    /* Architecture */
              UINT32  e_version;    /* Object file version */
              UINT32  e_entry;      /* Entry point virtual address */
              UINT32  e_phoff;      /* Program header table file offset */
              UINT32  e_shoff;      /* Section header table file offset */
              UINT32  e_flags;      /* Processor-specific flags */
              UINT16  e_ehsize;     /* ELF header size in bytes */
              UINT16  e_phentsize;  /* Program header table entry size */
              UINT16  e_phnum;      /* Program header table entry count */
              UINT16  e_shentsize;  /* Section header table entry size */
              UINT16  e_shnum;      /* Section header table entry count */
              UINT16  e_shstrndx;   /* Section header string table index */
          } elfhdr32;
  
          if (!elf_map_file_read(fmap, emfd, &elfhdr32, sizeof(elfhdr32), 0))
              return FALSE;
  
          memcpy(fmap->u.elf.elfhdr.e_ident, elfhdr32.e_ident, sizeof(e_ident));
          fmap->u.elf.elfhdr.e_type      = elfhdr32.e_type;
          fmap->u.elf.elfhdr.e_machine   = elfhdr32.e_machine;
          fmap->u.elf.elfhdr.e_version   = elfhdr32.e_version;
          fmap->u.elf.elfhdr.e_entry     = elfhdr32.e_entry;
          fmap->u.elf.elfhdr.e_phoff     = elfhdr32.e_phoff;
          fmap->u.elf.elfhdr.e_shoff     = elfhdr32.e_shoff;
          fmap->u.elf.elfhdr.e_flags     = elfhdr32.e_flags;
          fmap->u.elf.elfhdr.e_ehsize    = elfhdr32.e_ehsize;
          fmap->u.elf.elfhdr.e_phentsize = elfhdr32.e_phentsize;
          fmap->u.elf.elfhdr.e_phnum     = elfhdr32.e_phnum;
          fmap->u.elf.elfhdr.e_shentsize = elfhdr32.e_shentsize;
          fmap->u.elf.elfhdr.e_shnum     = elfhdr32.e_shnum;
          fmap->u.elf.elfhdr.e_shstrndx  = elfhdr32.e_shstrndx;
      }
      else
      {
          if (!elf_map_file_read(fmap, emfd, &fmap->u.elf.elfhdr, sizeof(fmap->u.elf.elfhdr), 0))
              return FALSE;
      }
  
      fmap->u.elf.sect = HeapAlloc(GetProcessHeap(), 0,
                                   fmap->u.elf.elfhdr.e_shnum * sizeof(fmap->u.elf.sect[0]));
      if (!fmap->u.elf.sect) return FALSE;
  
      for (i = 0; i < fmap->u.elf.elfhdr.e_shnum; i++)
      {
          if (!elf_map_shdr(emfd, fmap, i))
          {
              HeapFree(GetProcessHeap(), 0, fmap->u.elf.sect);
              fmap->u.elf.sect = NULL;
              return FALSE;
          }
          fmap->u.elf.sect[i].mapped = NULL;
      }
  
      /* grab size of module once loaded in memory */
      fmap->u.elf.elf_size = 0;
      fmap->u.elf.elf_start = ~0L;
      for (i = 0; i < fmap->u.elf.elfhdr.e_phnum; i++)
      {
          if (fmap->addr_size == 32)
          {
              struct
              {
                  UINT32  p_type;    /* Segment type */
                  UINT32  p_offset;  /* Segment file offset */
                  UINT32  p_vaddr;   /* Segment virtual address */
                  UINT32  p_paddr;   /* Segment physical address */
                  UINT32  p_filesz;  /* Segment size in file */
                  UINT32  p_memsz;   /* Segment size in memory */
                  UINT32  p_flags;   /* Segment flags */
                  UINT32  p_align;   /* Segment alignment */
              } phdr;
  
              if (elf_map_file_read(fmap, emfd, &phdr, sizeof(phdr),
                                    fmap->u.elf.elfhdr.e_phoff + i * sizeof(phdr)) &&
                  phdr.p_type == ELF_PT_LOAD)
              {
                  tmp = (phdr.p_vaddr + phdr.p_memsz + page_mask) & ~page_mask;
                  if (fmap->u.elf.elf_size < tmp) fmap->u.elf.elf_size = tmp;
                  if (phdr.p_vaddr < fmap->u.elf.elf_start) fmap->u.elf.elf_start = phdr.p_vaddr;
              }
          }
          else
          {
              struct
              {
                  UINT32  p_type;    /* Segment type */
                  UINT32  p_flags;   /* Segment flags */
                  UINT64  p_offset;  /* Segment file offset */
                  UINT64  p_vaddr;   /* Segment virtual address */
                  UINT64  p_paddr;   /* Segment physical address */
                  UINT64  p_filesz;  /* Segment size in file */
                  UINT64  p_memsz;   /* Segment size in memory */
                  UINT64  p_align;   /* Segment alignment */
              } phdr;
  
              if (elf_map_file_read(fmap, emfd, &phdr, sizeof(phdr),
                                    fmap->u.elf.elfhdr.e_phoff + i * sizeof(phdr)) &&
                  phdr.p_type == ELF_PT_LOAD)
              {
                  tmp = (phdr.p_vaddr + phdr.p_memsz + page_mask) & ~page_mask;
                  if (fmap->u.elf.elf_size < tmp) fmap->u.elf.elf_size = tmp;
                  if (phdr.p_vaddr < fmap->u.elf.elf_start) fmap->u.elf.elf_start = phdr.p_vaddr;
              }
          }
      }
      /* if non relocatable ELF, then remove fixed address from computation
       * otherwise, all addresses are zero based and start has no effect
       */
      fmap->u.elf.elf_size -= fmap->u.elf.elf_start;
  
      switch (emfd->kind)
      {
      case from_handle:
      case from_file: break;
      case from_process:
          if (!(fmap->u.elf.target_copy = HeapAlloc(GetProcessHeap(), 0, fmap->u.elf.elf_size)))
          {
              HeapFree(GetProcessHeap(), 0, fmap->u.elf.sect);
              return FALSE;
          }
          if (!ReadProcessMemory(emfd->u.process.handle, emfd->u.process.load_addr, fmap->u.elf.target_copy,
                                 fmap->u.elf.elf_size, NULL))
          {
              HeapFree(GetProcessHeap(), 0, fmap->u.elf.target_copy);
              HeapFree(GetProcessHeap(), 0, fmap->u.elf.sect);
              return FALSE;
          }
          break;
      }
      return TRUE;
  }
  
  BOOL elf_map_handle(HANDLE handle, struct image_file_map* fmap)
  {
      struct elf_map_file_data emfd;
      emfd.kind = from_handle;
      emfd.u.handle = handle;
      return elf_map_file(&emfd, fmap);
  }
  
  static void elf_module_remove(struct process* pcs, struct module_format* modfmt)
  {
      image_unmap_file(&modfmt->u.elf_info->file_map);
      HeapFree(GetProcessHeap(), 0, modfmt);
  }
  
  /******************************************************************
   *		elf_is_in_thunk_area
   *
   * Check whether an address lies within one of the thunk area we
   * know of.
   */
  int elf_is_in_thunk_area(ULONG_PTR addr,
                           const struct elf_thunk_area* thunks)
  {
      unsigned i;
  
      if (thunks) for (i = 0; thunks[i].symname; i++)
      {
          if (addr >= thunks[i].rva_start && addr < thunks[i].rva_end)
              return i;
      }
      return -1;
  }
  
  /******************************************************************
   *		elf_hash_symtab
   *
   * creating an internal hash table to ease use ELF symtab information lookup
   */
  static void elf_hash_symtab(struct module* module, struct pool* pool,
                              struct hash_table* ht_symtab, struct image_file_map* fmap,
                              struct elf_thunk_area* thunks)
  {
      int		                i, j, nsym;
      const char*                 strp;
      const char*                 symname;
      struct symt_compiland*      compiland = NULL;
      const char*                 ptr;
      struct symtab_elt*          ste;
      struct image_section_map    ism, ism_str;
      const char *symtab;
  
      if (!elf_find_section_type(fmap, ".symtab", ELF_SHT_SYMTAB, &ism) &&
          !elf_find_section_type(fmap, ".dynsym", ELF_SHT_DYNSYM, &ism)) return;
      if ((symtab = image_map_section(&ism)) == IMAGE_NO_MAP) return;
      ism_str.fmap = ism.fmap;
      ism_str.sidx = fmap->u.elf.sect[ism.sidx].shdr.sh_link;
      if ((strp = image_map_section(&ism_str)) == IMAGE_NO_MAP)
      {
          image_unmap_section(&ism);
          return;
      }
  
      nsym = image_get_map_size(&ism) /
             (fmap->addr_size == 32 ? sizeof(struct elf_sym32) : sizeof(struct elf_sym));
  
      for (j = 0; thunks[j].symname; j++)
          thunks[j].rva_start = thunks[j].rva_end = 0;
  
      for (i = 0; i < nsym; i++)
      {
          struct elf_sym sym;
          unsigned int type;
  
          if (fmap->addr_size == 32)
          {
              struct elf_sym32 *sym32 = &((struct elf_sym32 *)symtab)[i];
  
              sym.st_name  = sym32->st_name;
              sym.st_value = sym32->st_value;
              sym.st_size  = sym32->st_size;
              sym.st_info  = sym32->st_info;
              sym.st_other = sym32->st_other;
              sym.st_shndx = sym32->st_shndx;
          }
          else
              sym = ((struct elf_sym *)symtab)[i];
  
          type = sym.st_info & 0xf;
  
          /* Ignore certain types of entries which really aren't of that much
           * interest.
           */
          if ((type != ELF_STT_NOTYPE && type != ELF_STT_FILE && type != ELF_STT_OBJECT && type != ELF_STT_FUNC)
              || !sym.st_shndx)
          {
              continue;
          }
  
          symname = strp + sym.st_name;
  
          /* handle some specific symtab (that we'll throw away when done) */
          switch (type)
          {
          case ELF_STT_FILE:
              if (symname)
                  compiland = symt_new_compiland(module, sym.st_value,
                                                 source_new(module, NULL, symname));
              else
                  compiland = NULL;
              continue;
          case ELF_STT_NOTYPE:
              /* we are only interested in wine markers inserted by winebuild */
              for (j = 0; thunks[j].symname; j++)
              {
                  if (!strcmp(symname, thunks[j].symname))
                  {
                      thunks[j].rva_start = sym.st_value;
                      thunks[j].rva_end   = sym.st_value + sym.st_size;
                      break;
                  }
              }
              continue;
          }
  
          /* FIXME: we don't need to handle them (GCC internals)
           * Moreover, they screw up our symbol lookup :-/
           */
          if (symname[0] == '.' && symname[1] == 'L' && isdigit(symname[2]))
              continue;
  
          ste = pool_alloc(pool, sizeof(*ste));
          ste->ht_elt.name = symname;
          /* GCC emits, in some cases, a .<digit>+ suffix.
           * This is used for static variable inside functions, so
           * that we can have several such variables with same name in
           * the same compilation unit
           * We simply ignore that suffix when present (we also get rid
           * of it in stabs parsing)
           */
          ptr = symname + strlen(symname) - 1;
          if (isdigit(*ptr))
          {
              while (isdigit(*ptr) && ptr >= symname) ptr--;
              if (ptr > symname && *ptr == '.')
              {
                  char* n = pool_alloc(pool, ptr - symname + 1);
                  memcpy(n, symname, ptr - symname + 1);
                  n[ptr - symname] = '\0';
                  ste->ht_elt.name = n;
              }
          }
          ste->sym         = sym;
          ste->compiland   = compiland;
          ste->used        = 0;
          hash_table_add(ht_symtab, &ste->ht_elt);
      }
      /* as we added in the ht_symtab pointers to the symbols themselves,
       * we cannot unmap yet the sections, it will be done when we're over
       * with this ELF file
       */
  }
  
  /******************************************************************
   *		elf_lookup_symtab
   *
   * lookup a symbol by name in our internal hash table for the symtab
   */
  static const struct elf_sym *elf_lookup_symtab(const struct module* module,
                                                 const struct hash_table* ht_symtab,
                                                 const char* name, const struct symt* compiland)
  {
      struct symtab_elt*          weak_result = NULL; /* without compiland name */
      struct symtab_elt*          result = NULL;
      struct hash_table_iter      hti;
      struct symtab_elt*          ste;
      const char*                 compiland_name;
      const char*                 compiland_basename;
      const char*                 base;
  
      /* we need weak match up (at least) when symbols of same name, 
       * defined several times in different compilation units,
       * are merged in a single one (hence a different filename for c.u.)
       */
      if (compiland)
      {
          compiland_name = source_get(module,
                                      ((const struct symt_compiland*)compiland)->source);
          compiland_basename = file_nameA(compiland_name);
      }
      else compiland_name = compiland_basename = NULL;
      
      hash_table_iter_init(ht_symtab, &hti, name);
      while ((ste = hash_table_iter_up(&hti)))
      {
          if (ste->used || strcmp(ste->ht_elt.name, name)) continue;
  
          weak_result = ste;
          if ((ste->compiland && !compiland_name) || (!ste->compiland && compiland_name))
              continue;
          if (ste->compiland && compiland_name)
          {
              const char* filename = source_get(module, ste->compiland->source);
              if (strcmp(filename, compiland_name))
              {
                  base = file_nameA(filename);
                  if (strcmp(base, compiland_basename)) continue;
              }
          }
          if (result)
          {
              FIXME("Already found symbol %s (%s) in symtab %s @%08x and %s @%08x\n",
                    name, compiland_name,
                    source_get(module, result->compiland->source), (unsigned int)result->sym.st_value,
                    source_get(module, ste->compiland->source), (unsigned int)ste->sym.st_value);
          }
          else
          {
              result = ste;
              ste->used = 1;
          }
      }
      if (!result && !(result = weak_result))
      {
          FIXME("Couldn't find symbol %s!%s in symtab\n",
                debugstr_w(module->module.ModuleName), name);
          return NULL;
      }
      return &result->sym;
  }
  
  static BOOL elf_is_local_symbol(unsigned int info)
  {
      return !(info >> 4);
  }
  
  /******************************************************************
   *		elf_finish_stabs_info
   *
   * - get any relevant information (address & size) from the bits we got from the
   *   stabs debugging information
   */
  static void elf_finish_stabs_info(struct module* module, const struct hash_table* symtab)
  {
      struct hash_table_iter      hti;
      void*                       ptr;
      struct symt_ht*             sym;
      const struct elf_sym*       symp;
      struct elf_module_info*     elf_info = module->format_info[DFI_ELF]->u.elf_info;
  
      hash_table_iter_init(&module->ht_symbols, &hti, NULL);
      while ((ptr = hash_table_iter_up(&hti)))
      {
          sym = CONTAINING_RECORD(ptr, struct symt_ht, hash_elt);
          switch (sym->symt.tag)
          {
          case SymTagFunction:
              if (((struct symt_function*)sym)->address != elf_info->elf_addr &&
                  ((struct symt_function*)sym)->size)
              {
                  break;
              }
              symp = elf_lookup_symtab(module, symtab, sym->hash_elt.name, 
                                       ((struct symt_function*)sym)->container);
              if (symp)
              {
                  if (((struct symt_function*)sym)->address != elf_info->elf_addr &&
                      ((struct symt_function*)sym)->address != elf_info->elf_addr + symp->st_value)
                      FIXME("Changing address for %p/%s!%s from %08lx to %s\n",
                            sym, debugstr_w(module->module.ModuleName), sym->hash_elt.name,
                            ((struct symt_function*)sym)->address,
                            wine_dbgstr_longlong(elf_info->elf_addr + symp->st_value));
                  if (((struct symt_function*)sym)->size && ((struct symt_function*)sym)->size != symp->st_size)
                      FIXME("Changing size for %p/%s!%s from %08lx to %08x\n",
                            sym, debugstr_w(module->module.ModuleName), sym->hash_elt.name,
                            ((struct symt_function*)sym)->size, (unsigned int)symp->st_size);
  
                  ((struct symt_function*)sym)->address = elf_info->elf_addr + symp->st_value;
                  ((struct symt_function*)sym)->size    = symp->st_size;
              } else
                  FIXME("Couldn't find %s!%s\n",
                        debugstr_w(module->module.ModuleName), sym->hash_elt.name);
              break;
          case SymTagData:
              switch (((struct symt_data*)sym)->kind)
              {
              case DataIsGlobal:
              case DataIsFileStatic:
                  if (((struct symt_data*)sym)->u.var.kind != loc_absolute ||
                      ((struct symt_data*)sym)->u.var.offset != elf_info->elf_addr)
                      break;
                  symp = elf_lookup_symtab(module, symtab, sym->hash_elt.name, 
                                           ((struct symt_data*)sym)->container);
                  if (symp)
                  {
                      if (((struct symt_data*)sym)->u.var.offset != elf_info->elf_addr &&
                          ((struct symt_data*)sym)->u.var.offset != elf_info->elf_addr + symp->st_value)
                          FIXME("Changing address for %p/%s!%s from %08lx to %s\n",
                                sym, debugstr_w(module->module.ModuleName), sym->hash_elt.name,
                                ((struct symt_function*)sym)->address,
                                wine_dbgstr_longlong(elf_info->elf_addr + symp->st_value));
                      ((struct symt_data*)sym)->u.var.offset = elf_info->elf_addr + symp->st_value;
                      ((struct symt_data*)sym)->kind = elf_is_local_symbol(symp->st_info) ?
                          DataIsFileStatic : DataIsGlobal;
                  } else
                      FIXME("Couldn't find %s!%s\n",
                            debugstr_w(module->module.ModuleName), sym->hash_elt.name);
                  break;
              default:;
              }
              break;
          default:
              FIXME("Unsupported tag %u\n", sym->symt.tag);
              break;
          }
      }
      /* since we may have changed some addresses & sizes, mark the module to be resorted */
      module->sortlist_valid = FALSE;
  }
  
  /******************************************************************
   *		elf_load_wine_thunks
   *
   * creating the thunk objects for a wine native DLL
   */
  static int elf_new_wine_thunks(struct module* module, const struct hash_table* ht_symtab,
                                 const struct elf_thunk_area* thunks)
  {
      int		                j;
      struct hash_table_iter      hti;
      struct symtab_elt*          ste;
      DWORD_PTR                   addr;
      struct symt_ht*             symt;
  
      hash_table_iter_init(ht_symtab, &hti, NULL);
      while ((ste = hash_table_iter_up(&hti)))
      {
          if (ste->used) continue;
  
          addr = module->reloc_delta + ste->sym.st_value;
  
          j = elf_is_in_thunk_area(ste->sym.st_value, thunks);
          if (j >= 0) /* thunk found */
          {
              symt_new_thunk(module, ste->compiland, ste->ht_elt.name, thunks[j].ordinal,
                             addr, ste->sym.st_size);
          }
          else
          {
              ULONG64     ref_addr;
              struct location loc;
  
              symt = symt_find_nearest(module, addr);
              if (symt && !symt_get_address(&symt->symt, &ref_addr))
                  ref_addr = addr;
              if (!symt || addr != ref_addr)
              {
                  /* creating public symbols for all the ELF symbols which haven't been
                   * used yet (ie we have no debug information on them)
                   * That's the case, for example, of the .spec.c files
                   */
                  switch (ste->sym.st_info & 0xf)
                  {
                  case ELF_STT_FUNC:
                      symt_new_function(module, ste->compiland, ste->ht_elt.name,
                                        addr, ste->sym.st_size, NULL);
                      break;
                  case ELF_STT_OBJECT:
                      loc.kind = loc_absolute;
                      loc.reg = 0;
                      loc.offset = addr;
                      symt_new_global_variable(module, ste->compiland, ste->ht_elt.name,
                                               elf_is_local_symbol(ste->sym.st_info),
                                               loc, ste->sym.st_size, NULL);
                      break;
                  default:
                      FIXME("Shouldn't happen\n");
                      break;
                  }
                  /* FIXME: this is a hack !!!
                   * we are adding new symbols, but as we're parsing a symbol table
                   * (hopefully without duplicate symbols) we delay rebuilding the sorted
                   * module table until we're done with the symbol table
                   * Otherwise, as we intertwine symbols' add and lookup, performance
                   * is rather bad
                   */
                  module->sortlist_valid = TRUE;
              }
          }
      }
      /* see comment above */
      module->sortlist_valid = FALSE;
      return TRUE;
  }
  
  /******************************************************************
   *		elf_new_public_symbols
   *
   * Creates a set of public symbols from an ELF symtab
   */
  static int elf_new_public_symbols(struct module* module, const struct hash_table* symtab)
  {
      struct hash_table_iter      hti;
      struct symtab_elt*          ste;
  
      if (dbghelp_options & SYMOPT_NO_PUBLICS) return TRUE;
  
      /* FIXME: we're missing the ELF entry point here */
  
      hash_table_iter_init(symtab, &hti, NULL);
      while ((ste = hash_table_iter_up(&hti)))
      {
          symt_new_public(module, ste->compiland, ste->ht_elt.name,
                          FALSE,
                          module->reloc_delta + ste->sym.st_value,
                          ste->sym.st_size);
      }
      return TRUE;
  }
  
  /******************************************************************
   *		elf_load_debug_info_from_map
   *
   * Loads the symbolic information from ELF module which mapping is described
   * in fmap
   * the module has been loaded at 'load_offset' address, so symbols' address
   * relocation is performed.
   * CRC is checked if fmap->with_crc is TRUE
   * returns
   *	0 if the file doesn't contain symbolic info (or this info cannot be
   *	read or parsed)
   *	1 on success
   */
  static BOOL elf_load_debug_info_from_map(struct module* module,
                                           struct image_file_map* fmap,
                                           struct pool* pool,
                                           struct hash_table* ht_symtab)
  {
      BOOL                ret = FALSE, lret;
      struct elf_thunk_area thunks[] = 
      {
          {"__wine_spec_import_thunks",           THUNK_ORDINAL_NOTYPE, 0, 0},    /* inter DLL calls */
          {"__wine_spec_delayed_import_loaders",  THUNK_ORDINAL_LOAD,   0, 0},    /* delayed inter DLL calls */
          {"__wine_spec_delayed_import_thunks",   THUNK_ORDINAL_LOAD,   0, 0},    /* delayed inter DLL calls */
          {"__wine_delay_load",                   THUNK_ORDINAL_LOAD,   0, 0},    /* delayed inter DLL calls */
          {"__wine_spec_thunk_text_16",           -16,                  0, 0},    /* 16 => 32 thunks */
          {"__wine_spec_thunk_text_32",           -32,                  0, 0},    /* 32 => 16 thunks */
          {NULL,                                  0,                    0, 0}
      };
  
      module->module.SymType = SymExport;
  
      /* create a hash table for the symtab */
      elf_hash_symtab(module, pool, ht_symtab, fmap, thunks);
  
      if (!(dbghelp_options & SYMOPT_PUBLICS_ONLY))
      {
          struct image_section_map stab_sect, stabstr_sect;
  
          /* check if we need an alternate file (from debuglink or build-id) */
          ret = image_check_alternate(fmap, module);
  
          if (image_find_section(fmap, ".stab", &stab_sect) &&
              image_find_section(fmap, ".stabstr", &stabstr_sect))
          {
              const char* stab;
              const char* stabstr;
  
              stab = image_map_section(&stab_sect);
              stabstr = image_map_section(&stabstr_sect);
              if (stab != IMAGE_NO_MAP && stabstr != IMAGE_NO_MAP)
              {
                  /* OK, now just parse all of the stabs. */
                  lret = stabs_parse(module, module->format_info[DFI_ELF]->u.elf_info->elf_addr,
                                     stab, image_get_map_size(&stab_sect) / sizeof(struct stab_nlist), sizeof(struct stab_nlist),
                                     stabstr, image_get_map_size(&stabstr_sect),
                                     NULL, NULL);
                  if (lret)
                      /* and fill in the missing information for stabs */
                      elf_finish_stabs_info(module, ht_symtab);
                  else
                      WARN("Couldn't correctly read stabs\n");
                  ret = ret || lret;
              }
              image_unmap_section(&stab_sect);
              image_unmap_section(&stabstr_sect);
          }
          lret = dwarf2_parse(module, module->reloc_delta, thunks, fmap);
          ret = ret || lret;
      }
      if (wcsstr(module->module.ModuleName, S_ElfW) ||
          !wcscmp(module->module.ModuleName, S_WineLoaderW))
      {
          /* add the thunks for native libraries */
          if (!(dbghelp_options & SYMOPT_PUBLICS_ONLY))
              elf_new_wine_thunks(module, ht_symtab, thunks);
      }
      /* add all the public symbols from symtab */
      if (elf_new_public_symbols(module, ht_symtab) && !ret) ret = TRUE;
  
      return ret;
  }
  
  /******************************************************************
   *		elf_load_debug_info
   *
   * Loads ELF debugging information from the module image file.
   */
  static BOOL elf_load_debug_info(struct process* process, struct module* module)
  {
      BOOL                        ret = TRUE;
      struct pool                 pool;
      struct hash_table           ht_symtab;
      struct module_format*       modfmt;
  
      if (module->type != DMT_ELF || !(modfmt = module->format_info[DFI_ELF]) || !modfmt->u.elf_info)
      {
  	ERR("Bad elf module '%s'\n", debugstr_w(module->module.LoadedImageName));
  	return FALSE;
      }
  
      pool_init(&pool, 65536);
      hash_table_init(&pool, &ht_symtab, 256);
  
      ret = elf_load_debug_info_from_map(module, &modfmt->u.elf_info->file_map, &pool, &ht_symtab);
  
      pool_destroy(&pool);
      return ret;
  }
  
  /******************************************************************
   *		elf_fetch_file_info
   *
   * Gathers some more information for an ELF module from a given file
   */
  static BOOL elf_fetch_file_info(struct process* process, const WCHAR* name, ULONG_PTR load_addr, DWORD_PTR* base, DWORD* size, DWORD* checksum)
  {
      struct image_file_map fmap;
  
      struct elf_map_file_data    emfd;
  
      emfd.kind = from_file;
      emfd.u.file.filename = name;
      if (!elf_map_file(&emfd, &fmap)) return FALSE;
      if (base) *base = fmap.u.elf.elf_start;
      *size = fmap.u.elf.elf_size;
      *checksum = calc_crc32(fmap.u.elf.handle);
      image_unmap_file(&fmap);
      return TRUE;
  }
  
  static BOOL elf_load_file_from_fmap(struct process* pcs, const WCHAR* filename,
                                      struct image_file_map* fmap, ULONG_PTR load_offset,
                                      ULONG_PTR dyn_addr, struct elf_info* elf_info)
  {
      BOOL        ret = FALSE;
  
      if (elf_info->flags & ELF_INFO_DEBUG_HEADER)
      {
          struct image_section_map        ism;
  
          if (elf_find_section_type(fmap, ".dynamic", ELF_SHT_DYNAMIC, &ism))
          {
              char*           ptr = (char*)(ULONG_PTR)fmap->u.elf.sect[ism.sidx].shdr.sh_addr;
              ULONG_PTR       len;
  
              if (load_offset) ptr += load_offset - fmap->u.elf.elf_start;
  
              if (fmap->addr_size == 32)
              {
                  struct
                  {
                      INT32  d_tag;    /* Dynamic entry type */
                      UINT32 d_val;    /* Integer or address value */
                  } dyn;
  
                  do
                  {
                      if (!ReadProcessMemory(pcs->handle, ptr, &dyn, sizeof(dyn), &len) ||
                          len != sizeof(dyn))
                          return ret;
                      if (dyn.d_tag == ELF_DT_DEBUG)
                      {
                          elf_info->dbg_hdr_addr = dyn.d_val;
                          if (load_offset == 0 && dyn_addr == 0) /* likely the case */
                              /* Assume this module (the Wine loader) has been
                               * loaded at its preferred address */
                              dyn_addr = ism.fmap->u.elf.sect[ism.sidx].shdr.sh_addr;
                          break;
                      }
                      ptr += sizeof(dyn);
                  } while (dyn.d_tag);
                  if (!dyn.d_tag) return ret;
              }
              else
              {
                  struct
                  {
                      INT64  d_tag;    /* Dynamic entry type */
                      UINT64 d_val;    /* Integer or address value */
                  } dyn;
  
                  do
                  {
                      if (!ReadProcessMemory(pcs->handle, ptr, &dyn, sizeof(dyn), &len) ||
                          len != sizeof(dyn))
                          return ret;
                      if (dyn.d_tag == ELF_DT_DEBUG)
                      {
                          elf_info->dbg_hdr_addr = dyn.d_val;
                          if (load_offset == 0 && dyn_addr == 0) /* likely the case */
                              /* Assume this module (the Wine loader) has been
                               * loaded at its preferred address */
                              dyn_addr = ism.fmap->u.elf.sect[ism.sidx].shdr.sh_addr;
                          break;
                      }
                      ptr += sizeof(dyn);
                  } while (dyn.d_tag);
                  if (!dyn.d_tag) return ret;
              }
          }
          elf_end_find(fmap);
      }
  
      if (elf_info->flags & ELF_INFO_MODULE)
      {
          struct elf_module_info *elf_module_info;
          struct module_format*   modfmt;
          struct image_section_map ism;
          ULONG_PTR               modbase = load_offset;
  
          if (elf_find_section_type(fmap, ".dynamic", ELF_SHT_DYNAMIC, &ism))
          {
              ULONG_PTR rva_dyn = elf_get_map_rva(&ism);
  
              TRACE("For module %s, got ELF (start=%lx dyn=%lx), link_map (start=%lx dyn=%lx)\n",
                    debugstr_w(filename), (ULONG_PTR)fmap->u.elf.elf_start, rva_dyn,
                    load_offset, dyn_addr);
              if (dyn_addr && load_offset + rva_dyn != dyn_addr)
              {
                  WARN("\thave to relocate: %lx\n", dyn_addr - rva_dyn);
                  modbase = dyn_addr - rva_dyn;
              }
  	} else WARN("For module %s, no .dynamic section\n", debugstr_w(filename));
          elf_end_find(fmap);
  
          modfmt = HeapAlloc(GetProcessHeap(), 0,
                            sizeof(struct module_format) + sizeof(struct elf_module_info));
          if (!modfmt) return FALSE;
          elf_info->module = module_new(pcs, filename, DMT_ELF, FALSE, modbase,
                                        fmap->u.elf.elf_size, 0, calc_crc32(fmap->u.elf.handle));
          if (!elf_info->module)
          {
              HeapFree(GetProcessHeap(), 0, modfmt);
              return FALSE;
          }
          elf_info->module->reloc_delta = elf_info->module->module.BaseOfImage - fmap->u.elf.elf_start;
          elf_module_info = (void*)(modfmt + 1);
          elf_info->module->format_info[DFI_ELF] = modfmt;
          modfmt->module      = elf_info->module;
          modfmt->remove      = elf_module_remove;
          modfmt->loc_compute = NULL;
          modfmt->u.elf_info  = elf_module_info;
  
          elf_module_info->elf_addr = load_offset;
  
          elf_module_info->file_map = *fmap;
          elf_reset_file_map(fmap);
          if (dbghelp_options & SYMOPT_DEFERRED_LOADS)
          {
              elf_info->module->module.SymType = SymDeferred;
              ret = TRUE;
          }
          else ret = elf_load_debug_info(pcs, elf_info->module);
  
          elf_module_info->elf_mark = 1;
          elf_module_info->elf_loader = 0;
      } else ret = TRUE;
  
      if (elf_info->flags & ELF_INFO_NAME)
      {
          WCHAR*  ptr;
          ptr = HeapAlloc(GetProcessHeap(), 0, (lstrlenW(filename) + 1) * sizeof(WCHAR));
          if (ptr)
          {
              lstrcpyW(ptr, filename);
              elf_info->module_name = ptr;
          }
          else ret = FALSE;
      }
  
      return ret;
  }
  
  /******************************************************************
   *		elf_load_file
   *
   * Loads the information for ELF module stored in 'filename'
   * the module has been loaded at 'load_offset' address
   * returns
   *	-1 if the file cannot be found/opened
   *	0 if the file doesn't contain symbolic info (or this info cannot be
   *	read or parsed)
   *	1 on success
   */
  static BOOL elf_load_file(struct process* pcs, const WCHAR* filename,
                            ULONG_PTR load_offset, ULONG_PTR dyn_addr,
                            struct elf_info* elf_info)
  {
      BOOL                        ret = FALSE;
      struct image_file_map       fmap;
      struct elf_map_file_data    emfd;
  
      TRACE("Processing elf file '%s' at %08lx\n", debugstr_w(filename), load_offset);
  
      emfd.kind = from_file;
      emfd.u.file.filename = filename;
      if (!elf_map_file(&emfd, &fmap)) return ret;
  
      /* Next, we need to find a few of the internal ELF headers within
       * this thing.  We need the main executable header, and the section
       * table.
       */
      if (!fmap.u.elf.elf_start && !load_offset)
          ERR("Relocatable ELF %s, but no load address. Loading at 0x0000000\n",
              debugstr_w(filename));
  
      ret = elf_load_file_from_fmap(pcs, filename, &fmap, load_offset, dyn_addr, elf_info);
  
      image_unmap_file(&fmap);
  
      return ret;
  }
  
  struct elf_load_file_params
  {
      struct process  *process;
      ULONG_PTR        load_offset;
      ULONG_PTR        dyn_addr;
      struct elf_info *elf_info;
  };
  
  static BOOL elf_load_file_cb(void *param, HANDLE handle, const WCHAR *filename)
  {
      struct elf_load_file_params *load_file = param;
      return elf_load_file(load_file->process, filename, load_file->load_offset, load_file->dyn_addr, load_file->elf_info);
  }
  
  /******************************************************************
   *		elf_search_auxv
   *
   * locate some a value from the debuggee auxiliary vector
   */
  static BOOL elf_search_auxv(const struct process* pcs, unsigned type, ULONG_PTR* val)
  {
      char        buffer[sizeof(SYMBOL_INFO) + MAX_SYM_NAME];
      SYMBOL_INFO*si = (SYMBOL_INFO*)buffer;
      BYTE*       addr;
      BYTE*       str;
      BYTE*       str_max;
  
      si->SizeOfStruct = sizeof(*si);
      si->MaxNameLen = MAX_SYM_NAME;
      if (!SymFromName(pcs->handle, "libwine.so.1!__wine_main_environ", si) ||
          !(addr = (void*)(DWORD_PTR)si->Address) ||
          !ReadProcessMemory(pcs->handle, addr, &addr, sizeof(addr), NULL) ||
          !addr)
      {
          FIXME("can't find symbol in module\n");
          return FALSE;
      }
      /* walk through envp[] */
      /* envp[] strings are located after the auxiliary vector, so protect the walk */
      str_max = (void*)(DWORD_PTR)~0L;
      while (ReadProcessMemory(pcs->handle, addr, &str, sizeof(str), NULL) &&
             (addr = (void*)((DWORD_PTR)addr + sizeof(str))) != NULL && str != NULL)
          str_max = min(str_max, str);
  
      /* Walk through the end of envp[] array.
       * Actually, there can be several NULLs at the end of envp[]. This happens when an env variable is
       * deleted, the last entry is replaced by an extra NULL.
       */
      while (addr < str_max && ReadProcessMemory(pcs->handle, addr, &str, sizeof(str), NULL) && str == NULL)
          addr = (void*)((DWORD_PTR)addr + sizeof(str));
  
      if (pcs->is_64bit)
      {
          struct
          {
              UINT64 a_type;
              UINT64 a_val;
          } auxv;
  
          while (ReadProcessMemory(pcs->handle, addr, &auxv, sizeof(auxv), NULL) && auxv.a_type)
          {
              if (auxv.a_type == type)
              {
                  *val = auxv.a_val;
                  return TRUE;
              }
              addr += sizeof(auxv);
          }
      }
      else
      {
          struct
          {
              UINT32 a_type;
              UINT32 a_val;
          } auxv;
  
          while (ReadProcessMemory(pcs->handle, addr, &auxv, sizeof(auxv), NULL) && auxv.a_type)
          {
              if (auxv.a_type == type)
              {
                  *val = auxv.a_val;
                  return TRUE;
              }
              addr += sizeof(auxv);
          }
      }
  
      return FALSE;
  }
  
  /******************************************************************
   *		elf_search_and_load_file
   *
   * lookup a file in standard ELF locations, and if found, load it
   */
  static BOOL elf_search_and_load_file(struct process* pcs, const WCHAR* filename,
                                       ULONG_PTR load_offset, ULONG_PTR dyn_addr,
                                       struct elf_info* elf_info)
  {
      BOOL                ret = FALSE;
      struct module*      module;
      static const WCHAR  S_libstdcPPW[] = {'l','i','b','s','t','d','c','+','+','\0'};
  
      if (filename == NULL || *filename == '\0') return FALSE;
      if ((module = module_is_already_loaded(pcs, filename)))
      {
          elf_info->module = module;
          elf_info->module->format_info[DFI_ELF]->u.elf_info->elf_mark = 1;
          return module->module.SymType;
      }
  
      if (wcsstr(filename, S_libstdcPPW)) return FALSE; /* We know we can't do it */
      ret = elf_load_file(pcs, filename, load_offset, dyn_addr, elf_info);
      /* if relative pathname, try some absolute base dirs */
      if (!ret && filename == file_name(filename))
      {
          struct elf_load_file_params load_elf;
          load_elf.process     = pcs;
          load_elf.load_offset = load_offset;
          load_elf.dyn_addr    = dyn_addr;
          load_elf.elf_info    = elf_info;
  
          ret = search_unix_path(filename, process_getenv(pcs, L"LD_LIBRARY_PATH"), elf_load_file_cb, &load_elf)
              || search_dll_path(pcs, filename, elf_load_file_cb, &load_elf);
      }
  
      return ret;
  }
  
  typedef BOOL (*enum_elf_modules_cb)(const WCHAR*, ULONG_PTR load_addr,
                                      ULONG_PTR dyn_addr, BOOL is_system, void* user);
  
  /******************************************************************
   *		elf_enum_modules_internal
   *
   * Enumerate ELF modules from a running process
   */
  static BOOL elf_enum_modules_internal(const struct process* pcs,
                                        const WCHAR* main_name,
                                        enum_elf_modules_cb cb, void* user)
  {
      WCHAR bufstrW[MAX_PATH];
      char bufstr[256];
      ULONG_PTR lm_addr;
  
      if (pcs->is_64bit)
      {
          struct
          {
              UINT32 r_version;
              UINT64 r_map;
              UINT64 r_brk;
              UINT32 r_state;
              UINT64 r_ldbase;
          } dbg_hdr;
          struct
          {
              UINT64 l_addr;
              UINT64 l_name;
              UINT64 l_ld;
              UINT64 l_next, l_prev;
          } lm;
  
          if (!pcs->dbg_hdr_addr || !read_process_memory(pcs, pcs->dbg_hdr_addr, &dbg_hdr, sizeof(dbg_hdr)))
              return FALSE;
  
          /* Now walk the linked list.  In all known ELF implementations,
           * the dynamic loader maintains this linked list for us.  In some
           * cases the first entry doesn't appear with a name, in other cases it
           * does.
           */
          for (lm_addr = dbg_hdr.r_map; lm_addr; lm_addr = lm.l_next)
          {
              if (!read_process_memory(pcs, lm_addr, &lm, sizeof(lm)))
                  return FALSE;
  
              if (lm.l_prev && /* skip first entry, normally debuggee itself */
                  lm.l_name && read_process_memory(pcs, lm.l_name, bufstr, sizeof(bufstr)))
              {
                  bufstr[sizeof(bufstr) - 1] = '\0';
                  MultiByteToWideChar(CP_UNIXCP, 0, bufstr, -1, bufstrW, ARRAY_SIZE(bufstrW));
                  if (main_name && !bufstrW[0]) lstrcpyW(bufstrW, main_name);
                  if (!cb(bufstrW, (ULONG_PTR)lm.l_addr, (ULONG_PTR)lm.l_ld, FALSE, user))
                      break;
              }
          }
      }
      else
      {
          struct
          {
              UINT32 r_version;
              UINT32 r_map;
              UINT32 r_brk;
              UINT32 r_state;
              UINT32 r_ldbase;
          } dbg_hdr;
          struct
          {
              UINT32 l_addr;
              UINT32 l_name;
              UINT32 l_ld;
              UINT32 l_next, l_prev;
          } lm;
  
          if (!pcs->dbg_hdr_addr || !read_process_memory(pcs, pcs->dbg_hdr_addr, &dbg_hdr, sizeof(dbg_hdr)))
              return FALSE;
  
          /* Now walk the linked list.  In all known ELF implementations,
           * the dynamic loader maintains this linked list for us.  In some
           * cases the first entry doesn't appear with a name, in other cases it
           * does.
           */
          for (lm_addr = dbg_hdr.r_map; lm_addr; lm_addr = lm.l_next)
          {
              if (!read_process_memory(pcs, lm_addr, &lm, sizeof(lm)))
                  return FALSE;
  
              if (lm.l_prev && /* skip first entry, normally debuggee itself */
                  lm.l_name && read_process_memory(pcs, lm.l_name, bufstr, sizeof(bufstr)))
              {
                  bufstr[sizeof(bufstr) - 1] = '\0';
                  MultiByteToWideChar(CP_UNIXCP, 0, bufstr, -1, bufstrW, ARRAY_SIZE(bufstrW));
                  if (main_name && !bufstrW[0]) lstrcpyW(bufstrW, main_name);
                  if (!cb(bufstrW, (ULONG_PTR)lm.l_addr, (ULONG_PTR)lm.l_ld, FALSE, user))
                      break;
              }
          }
      }
  
      if (!lm_addr)
      {
          ULONG_PTR ehdr_addr;
  
          if (elf_search_auxv(pcs, ELF_AT_SYSINFO_EHDR, &ehdr_addr))
          {
              static const WCHAR vdsoW[] = {'[','v','d','s','o',']','.','s','o',0};
              cb(vdsoW, ehdr_addr, 0, TRUE, user);
          }
      }
      return TRUE;
  }
  
  struct elf_enum_user
  {
      enum_modules_cb     cb;
      void*               user;
  };
  
  static BOOL elf_enum_modules_translate(const WCHAR* name, ULONG_PTR load_addr,
                                         ULONG_PTR dyn_addr, BOOL is_system, void* user)
  {
      struct elf_enum_user*       eeu = user;
      return eeu->cb(name, load_addr, eeu->user);
  }
  
  /******************************************************************
   *		elf_enum_modules
   *
   * Enumerates the ELF loaded modules from a running target (hProc)
   * This function doesn't require that someone has called SymInitialize
   * on this very process.
   */
  static BOOL elf_enum_modules(struct process* process, enum_modules_cb cb, void* user)
  {
      struct elf_info     elf_info;
      BOOL                ret;
      struct elf_enum_user eeu;
  
      elf_info.flags = ELF_INFO_DEBUG_HEADER | ELF_INFO_NAME;
      elf_info.module_name = NULL;
      eeu.cb = cb;
      eeu.user = user;
      ret = elf_enum_modules_internal(process, elf_info.module_name, elf_enum_modules_translate, &eeu);
      HeapFree(GetProcessHeap(), 0, (char*)elf_info.module_name);
      return ret;
  }
  
  struct elf_load
  {
      struct process*     pcs;
      struct elf_info     elf_info;
      const WCHAR*        name;
      BOOL                ret;
  };
  
  /******************************************************************
   *		elf_load_cb
   *
   * Callback for elf_load_module, used to walk the list of loaded
   * modules.
   */
  static BOOL elf_load_cb(const WCHAR* name, ULONG_PTR load_addr,
                          ULONG_PTR dyn_addr, BOOL is_system, void* user)
  {
      struct elf_load*    el = user;
      BOOL                ret = TRUE;
      const WCHAR*        p;
  
      if (is_system) /* virtual ELF module, created by system. handle it from memory */
      {
          struct module*                  module;
          struct elf_map_file_data        emfd;
          struct image_file_map           fmap;
  
          if ((module = module_is_already_loaded(el->pcs, name)))
          {
              el->elf_info.module = module;
              el->elf_info.module->format_info[DFI_ELF]->u.elf_info->elf_mark = 1;
              return module->module.SymType;
          }
  
          emfd.kind = from_process;
          emfd.u.process.handle = el->pcs->handle;
          emfd.u.process.load_addr = (void*)load_addr;
  
          if (elf_map_file(&emfd, &fmap))
              el->ret = elf_load_file_from_fmap(el->pcs, name, &fmap, load_addr, 0, &el->elf_info);
          return TRUE;
      }
      if (el->name)
      {
          /* memcmp is needed for matches when bufstr contains also version information
           * el->name: libc.so, name: libc.so.6.0
           */
          p = file_name(name);
      }
  
      if (!el->name || !memcmp(p, el->name, lstrlenW(el->name) * sizeof(WCHAR)))
      {
          el->ret = elf_search_and_load_file(el->pcs, name, load_addr, dyn_addr, &el->elf_info);
          if (el->name) ret = FALSE;
      }
  
      return ret;
  }
  
  /******************************************************************
   *		elf_load_module
   *
   * loads an ELF module and stores it in process' module list
   * Also, find module real name and load address from
   * the real loaded modules list in pcs address space
   */
  static struct module* elf_load_module(struct process* pcs, const WCHAR* name, ULONG_PTR addr)
  {
      struct elf_load     el;
  
      TRACE("(%p %s %08lx)\n", pcs, debugstr_w(name), addr);
  
      el.elf_info.flags = ELF_INFO_MODULE;
      el.ret = FALSE;
  
      if (pcs->dbg_hdr_addr) /* we're debugging a life target */
      {
          el.pcs = pcs;
          /* do only the lookup from the filename, not the path (as we lookup module
           * name in the process' loaded module list)
           */
          el.name = file_name(name);
          el.ret = FALSE;
  
          if (!elf_enum_modules_internal(pcs, NULL, elf_load_cb, &el))
              return NULL;
      }
      else if (addr)
      {
          el.name = name;
          el.ret = elf_search_and_load_file(pcs, el.name, addr, 0, &el.elf_info);
      }
      if (!el.ret) return NULL;
      assert(el.elf_info.module);
      return el.elf_info.module;
  }
  
  /******************************************************************
   *		elf_synchronize_module_list
   *
   * this function rescans the debuggee module's list and synchronizes it with
   * the one from 'pcs', i.e.:
   * - if a module is in debuggee and not in pcs, it's loaded into pcs
   * - if a module is in pcs and not in debuggee, it's unloaded from pcs
   */
  static BOOL elf_synchronize_module_list(struct process* pcs)
  {
      struct module*      module;
      struct elf_load     el;
  
      for (module = pcs->lmodules; module; module = module->next)
      {
          if (module->type == DMT_ELF && !module->is_virtual)
              module->format_info[DFI_ELF]->u.elf_info->elf_mark = 0;
      }
  
      el.pcs = pcs;
      el.elf_info.flags = ELF_INFO_MODULE;
      el.ret = FALSE;
      el.name = NULL; /* fetch all modules */
  
      if (!elf_enum_modules_internal(pcs, NULL, elf_load_cb, &el))
          return FALSE;
  
      module = pcs->lmodules;
      while (module)
      {
          if (module->type == DMT_ELF && !module->is_virtual)
          {
              struct elf_module_info* elf_info = module->format_info[DFI_ELF]->u.elf_info;
  
              if (!elf_info->elf_mark && !elf_info->elf_loader)
              {
                  module_remove(pcs, module);
                  /* restart all over */
                  module = pcs->lmodules;
                  continue;
              }
          }
          module = module->next;
      }
      return TRUE;
  }
  
  static const struct loader_ops elf_loader_ops =
  {
      elf_synchronize_module_list,
      elf_load_module,
      elf_load_debug_info,
      elf_enum_modules,
      elf_fetch_file_info,
  };
  
  /******************************************************************
   *		elf_read_wine_loader_dbg_info
   *
   * Try to find a decent wine executable which could have loaded the debuggee
   */
  BOOL elf_read_wine_loader_dbg_info(struct process* pcs, ULONG_PTR addr)
  {
      struct elf_info     elf_info;
      BOOL ret;
  
      elf_info.flags = ELF_INFO_DEBUG_HEADER | ELF_INFO_MODULE;
      ret = elf_search_and_load_file(pcs, get_wine_loader_name(pcs), addr, 0, &elf_info);
      if (!ret || !elf_info.dbg_hdr_addr) return FALSE;
  
      TRACE("Found ELF debug header %#lx\n", elf_info.dbg_hdr_addr);
      elf_info.module->format_info[DFI_ELF]->u.elf_info->elf_loader = 1;
      module_set_module(elf_info.module, S_WineLoaderW);
      pcs->dbg_hdr_addr = elf_info.dbg_hdr_addr;
      pcs->loader = &elf_loader_ops;
      return TRUE;
  }
  