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glibc  2.9
Classes | Defines | Functions | Variables
readlib.c File Reference
#include <a.out.h>
#include <elf.h>
#include <error.h>
#include <libintl.h>
#include <link.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <gnu/lib-names.h>
#include <ldconfig.h>
#include <readelflib.c>

Go to the source code of this file.

Classes

struct  known_names

Defines

#define Elf32_CLASS   ELFCLASS32
#define Elf64_CLASS   ELFCLASS64

Functions

int process_file (const char *real_file_name, const char *file_name, const char *lib, int *flag, unsigned int *osversion, char **soname, int is_link, struct stat64 *stat_buf)
char * implicit_soname (const char *lib, int flag)

Variables

static struct known_names []

Class Documentation

struct known_names

Definition at line 43 of file readlib.c.

Class Members
int flag
const char * soname

Define Documentation

#define Elf32_CLASS   ELFCLASS32

Definition at line 40 of file readlib.c.

#define Elf64_CLASS   ELFCLASS64

Definition at line 41 of file readlib.c.


Function Documentation

char* implicit_soname ( const char *  lib,
int  flag 
)

Definition at line 185 of file readlib.c.

{
  char *soname = xstrdup (lib);

  if ((flag & FLAG_TYPE_MASK) != FLAG_LIBC4)
    return soname;

  /* Aout files don't have a soname, just return the name
     including the major number.  */
  char *major = strstr (soname, ".so.");
  if (major)
    {
      char *dot = strstr (major + 4, ".");
      if (dot)
       *dot = '\0';
    }
  return soname;
}

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int process_file ( const char *  real_file_name,
const char *  file_name,
const char *  lib,
int flag,
unsigned int osversion,
char **  soname,
int  is_link,
struct stat64 stat_buf 
)

Definition at line 70 of file readlib.c.

{
  FILE *file;
  struct stat64 statbuf;
  void *file_contents;
  int ret;
  ElfW(Ehdr) *elf_header;
  struct exec *aout_header;

  ret = 0;
  *flag = FLAG_ANY;
  *soname = NULL;

  file = fopen (real_file_name, "rb");
  if (file == NULL)
    {
      /* No error for stale symlink.  */
      if (is_link && strstr (file_name, ".so") != NULL)
       return 1;
      error (0, 0, _("Input file %s not found.\n"), file_name);
      return 1;
    }

  if (fstat64 (fileno (file), &statbuf) < 0)
    {
      error (0, 0, _("Cannot fstat file %s.\n"), file_name);
      fclose (file);
      return 1;
    }

  /* Check that the file is large enough so that we can access the
     information.  We're only checking the size of the headers here.  */
  if ((size_t) statbuf.st_size < sizeof (struct exec)
      || (size_t) statbuf.st_size < sizeof (ElfW(Ehdr)))
    {
      if (statbuf.st_size == 0)
       error (0, 0, _("File %s is empty, not checked."), file_name);
      else
       {
         char buf[SELFMAG];
         size_t n = MIN (statbuf.st_size, SELFMAG);
         if (fread (buf, n, 1, file) == 1 && memcmp (buf, ELFMAG, n) == 0)
           error (0, 0, _("File %s is too small, not checked."), file_name);
       }
      fclose (file);
      return 1;
    }

  file_contents = mmap (0, statbuf.st_size, PROT_READ, MAP_SHARED,
                     fileno (file), 0);
  if (file_contents == MAP_FAILED)
    {
      error (0, 0, _("Cannot mmap file %s.\n"), file_name);
      fclose (file);
      return 1;
    }

  /* First check if this is an aout file.  */
  aout_header = (struct exec *) file_contents;
  if (N_MAGIC (*aout_header) == ZMAGIC
#ifdef QMAGIC               /* Linuxism.  */
      || N_MAGIC (*aout_header) == QMAGIC
#endif
      )
    {
      /* Aout files don't have a soname, just return the name
        including the major number.  */
      char *copy, *major, *dot;
      copy = xstrdup (lib);
      major = strstr (copy, ".so.");
      if (major)
       {
         dot = strstr (major + 4, ".");
         if (dot)
           *dot = '\0';
       }
      *soname = copy;
      *flag = FLAG_LIBC4;
      goto done;
    }

  elf_header = (ElfW(Ehdr) *) file_contents;
  if (memcmp (elf_header->e_ident, ELFMAG, SELFMAG) != 0)
    {
      /* The file is neither ELF nor aout.  Check if it's a linker
        script, like libc.so - otherwise complain.  Only search the
        beginning of the file.  */
      size_t len = MIN (statbuf.st_size, 512);
      if (memmem (file_contents, len, "GROUP", 5) == NULL
         && memmem (file_contents, len, "GNU ld script", 13) == NULL)
       error (0, 0, _("%s is not an ELF file - it has the wrong magic bytes at the start.\n"),
              file_name);
      ret = 1;
    }
  /* Libraries have to be shared object files.  */
  else if (elf_header->e_type != ET_DYN)
    ret = 1;
  else if (process_elf_file (file_name, lib, flag, osversion, soname,
                          file_contents, statbuf.st_size))
    ret = 1;

 done:
  /* Clean up allocated memory and resources.  */
  munmap (file_contents, statbuf.st_size);
  fclose (file);

  *stat_buf = statbuf;
  return ret;
}

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Variable Documentation

static struct known_names [static]
Initial value:
{
  { "/lib/" LD_SO, FLAG_ELF_LIBC6 },



}

Definition at line 49 of file readlib.c.