/* Locate source files and line information for given addresses
   Copyright (C) 2005-2010, 2012 Red Hat, Inc.
   This file is part of elfutils.
   Written by Ulrich Drepper <drepper@redhat.com>, 2005.

   This file is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   elfutils 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <argp.h>
#include <assert.h>
#include <errno.h>
#include <error.h>
#include <fcntl.h>
#include <inttypes.h>
#include <libdwfl.h>
#include <dwarf.h>
#include <libintl.h>
#include <locale.h>
#include <mcheck.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <system.h>


/* Name and version of program.  */
static void print_version (FILE *stream, struct argp_state *state);
ARGP_PROGRAM_VERSION_HOOK_DEF = print_version;

/* Bug report address.  */
ARGP_PROGRAM_BUG_ADDRESS_DEF = PACKAGE_BUGREPORT;


/* Values for the parameters which have no short form.  */
#define OPT_DEMANGLER 0x100

/* Definitions of arguments for argp functions.  */
static const struct argp_option options[] =
{
  { NULL, 0, NULL, 0, N_("Output selection options:"), 2 },
  { "basenames", 's', NULL, 0, N_("Show only base names of source files"), 0 },
  { "absolute", 'A', NULL, 0,
    N_("Show absolute file names using compilation directory"), 0 },
  { "functions", 'f', NULL, 0, N_("Also show function names"), 0 },
  { "symbols", 'S', NULL, 0, N_("Also show symbol or section names"), 0 },
  { "flags", 'F', NULL, 0, N_("Also show line table flags"), 0 },
  { "section", 'j', "NAME", 0,
    N_("Treat addresses as offsets relative to NAME section."), 0 },

  { NULL, 0, NULL, 0, N_("Miscellaneous:"), 0 },
  /* Unsupported options.  */
  { "target", 'b', "ARG", OPTION_HIDDEN, NULL, 0 },
  { "demangle", 'C', "ARG", OPTION_HIDDEN | OPTION_ARG_OPTIONAL, NULL, 0 },
  { "demangler", OPT_DEMANGLER, "ARG", OPTION_HIDDEN, NULL, 0 },
  { NULL, 0, NULL, 0, NULL, 0 }
};

/* Short description of program.  */
static const char doc[] = N_("\
Locate source files and line information for ADDRs (in a.out by default).");

/* Strings for arguments in help texts.  */
static const char args_doc[] = N_("[ADDR...]");

/* Prototype for option handler.  */
static error_t parse_opt (int key, char *arg, struct argp_state *state);

static struct argp_child argp_children[2]; /* [0] is set in main.  */

/* Data structure to communicate with argp functions.  */
static const struct argp argp =
{
  options, parse_opt, args_doc, doc, argp_children, NULL, NULL
};


/* Handle ADDR.  */
static int handle_address (const char *addr, Dwfl *dwfl);


/* True if only base names of files should be shown.  */
static bool only_basenames;

/* True if absolute file names based on DW_AT_comp_dir should be shown.  */
static bool use_comp_dir;

/* True if line flags should be shown.  */
static bool show_flags;

/* True if function names should be shown.  */
static bool show_functions;

/* True if ELF symbol or section info should be shown.  */
static bool show_symbols;

/* If non-null, take address parameters as relative to named section.  */
static const char *just_section;


int
main (int argc, char *argv[])
{
  int remaining;
  int result = 0;

  /* Make memory leak detection possible.  */
  mtrace ();

  /* We use no threads here which can interfere with handling a stream.  */
  (void) __fsetlocking (stdout, FSETLOCKING_BYCALLER);

  /* Set locale.  */
  (void) setlocale (LC_ALL, "");

  /* Make sure the message catalog can be found.  */
  (void) bindtextdomain (PACKAGE_TARNAME, LOCALEDIR);

  /* Initialize the message catalog.  */
  (void) textdomain (PACKAGE_TARNAME);

  /* Parse and process arguments.  This includes opening the modules.  */
  argp_children[0].argp = dwfl_standard_argp ();
  argp_children[0].group = 1;
  Dwfl *dwfl = NULL;
  (void) argp_parse (&argp, argc, argv, 0, &remaining, &dwfl);
  assert (dwfl != NULL);

  /* Now handle the addresses.  In case none are given on the command
     line, read from stdin.  */
  if (remaining == argc)
    {
      /* We use no threads here which can interfere with handling a stream.  */
      (void) __fsetlocking (stdin, FSETLOCKING_BYCALLER);

      char *buf = NULL;
      size_t len = 0;
      while (!feof_unlocked (stdin))
	{
	  if (getline (&buf, &len, stdin) < 0)
	    break;

	  result = handle_address (buf, dwfl);
	}

      free (buf);
    }
  else
    {
      do
	result = handle_address (argv[remaining], dwfl);
      while (++remaining < argc);
    }

  return result;
}


/* Print the version information.  */
static void
print_version (FILE *stream, struct argp_state *state __attribute__ ((unused)))
{
  fprintf (stream, "addr2line (%s) %s\n", PACKAGE_NAME, PACKAGE_VERSION);
  fprintf (stream, gettext ("\
Copyright (C) %s Red Hat, Inc.\n\
This is free software; see the source for copying conditions.  There is NO\n\
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
"), "2012");
  fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");
}


/* Handle program arguments.  */
static error_t
parse_opt (int key, char *arg, struct argp_state *state)
{
  switch (key)
    {
    case ARGP_KEY_INIT:
      state->child_inputs[0] = state->input;
      break;

    case 'b':
    case 'C':
    case OPT_DEMANGLER:
      /* Ignored for compatibility.  */
      break;

    case 's':
      only_basenames = true;
      break;

    case 'A':
      use_comp_dir = true;
      break;

    case 'f':
      show_functions = true;
      break;

    case 'F':
      show_flags = true;
      break;

    case 'S':
      show_symbols = true;
      break;

    case 'j':
      just_section = arg;
      break;

    default:
      return ARGP_ERR_UNKNOWN;
    }
  return 0;
}


static bool
print_dwarf_function (Dwfl_Module *mod, Dwarf_Addr addr)
{
  Dwarf_Addr bias = 0;
  Dwarf_Die *cudie = dwfl_module_addrdie (mod, addr, &bias);

  Dwarf_Die *scopes;
  int nscopes = dwarf_getscopes (cudie, addr - bias, &scopes);
  if (nscopes <= 0)
    return false;

  for (int i = 0; i < nscopes; ++i)
    switch (dwarf_tag (&scopes[i]))
      {
      case DW_TAG_subprogram:
	{
	  const char *name = dwarf_diename (&scopes[i]);
	  if (name == NULL)
	    return false;
	  puts (name);
	  return true;
	}

      case DW_TAG_inlined_subroutine:
	{
	  const char *name = dwarf_diename (&scopes[i]);
	  if (name == NULL)
	    return false;
	  printf ("%s inlined", name);

	  Dwarf_Files *files;
	  if (dwarf_getsrcfiles (cudie, &files, NULL) == 0)
	    {
	      Dwarf_Attribute attr_mem;
	      Dwarf_Word val;
	      if (dwarf_formudata (dwarf_attr (&scopes[i],
					       DW_AT_call_file,
					       &attr_mem), &val) == 0)
		{
		  const char *file = dwarf_filesrc (files, val, NULL, NULL);
		  unsigned int lineno = 0;
		  unsigned int colno = 0;
		  if (dwarf_formudata (dwarf_attr (&scopes[i],
						   DW_AT_call_line,
						   &attr_mem), &val) == 0)
		    lineno = val;
		  if (dwarf_formudata (dwarf_attr (&scopes[i],
						   DW_AT_call_column,
						   &attr_mem), &val) == 0)
		    colno = val;

		  const char *comp_dir = "";
		  const char *comp_dir_sep = "";

		  if (file == NULL)
		    file = "???";
		  else if (only_basenames)
		    file = basename (file);
		  else if (use_comp_dir && file[0] != '/')
		    {
		      const char *const *dirs;
		      size_t ndirs;
		      if (dwarf_getsrcdirs (files, &dirs, &ndirs) == 0
			  && dirs[0] != NULL)
			{
			  comp_dir = dirs[0];
			  comp_dir_sep = "/";
			}
		    }

		  if (lineno == 0)
		    printf (" from %s%s%s",
			    comp_dir, comp_dir_sep, file);
		  else if (colno == 0)
		    printf (" at %s%s%s:%u",
			    comp_dir, comp_dir_sep, file, lineno);
		  else
		    printf (" at %s%s%s:%u:%u",
			    comp_dir, comp_dir_sep, file, lineno, colno);
		}
	    }
	  printf (" in ");
	  continue;
	}
      }

  return false;
}

static void
print_addrsym (Dwfl_Module *mod, GElf_Addr addr)
{
  GElf_Sym s;
  GElf_Word shndx;
  const char *name = dwfl_module_addrsym (mod, addr, &s, &shndx);
  if (name == NULL)
    {
      /* No symbol name.  Get a section name instead.  */
      int i = dwfl_module_relocate_address (mod, &addr);
      if (i >= 0)
	name = dwfl_module_relocation_info (mod, i, NULL);
      if (name == NULL)
	puts ("??");
      else
	printf ("(%s)+%#" PRIx64 "\n", name, addr);
    }
  else if (addr == s.st_value)
    puts (name);
  else
    printf ("%s+%#" PRIx64 "\n", name, addr - s.st_value);
}

static int
see_one_module (Dwfl_Module *mod,
		void **userdata __attribute__ ((unused)),
		const char *name __attribute__ ((unused)),
		Dwarf_Addr start __attribute__ ((unused)),
		void *arg)
{
  Dwfl_Module **result = arg;
  if (*result != NULL)
    return DWARF_CB_ABORT;
  *result = mod;
  return DWARF_CB_OK;
}

static int
find_symbol (Dwfl_Module *mod,
	     void **userdata __attribute__ ((unused)),
	     const char *name __attribute__ ((unused)),
	     Dwarf_Addr start __attribute__ ((unused)),
	     void *arg)
{
  const char *looking_for = ((void **) arg)[0];
  GElf_Sym *symbol = ((void **) arg)[1];

  int n = dwfl_module_getsymtab (mod);
  for (int i = 1; i < n; ++i)
    {
      const char *symbol_name = dwfl_module_getsym (mod, i, symbol, NULL);
      if (symbol_name == NULL || symbol_name[0] == '\0')
	continue;
      switch (GELF_ST_TYPE (symbol->st_info))
	{
	case STT_SECTION:
	case STT_FILE:
	case STT_TLS:
	  break;
	default:
	  if (!strcmp (symbol_name, looking_for))
	    {
	      ((void **) arg)[0] = NULL;
	      return DWARF_CB_ABORT;
	    }
	}
    }

  return DWARF_CB_OK;
}

static bool
adjust_to_section (const char *name, uintmax_t *addr, Dwfl *dwfl)
{
  /* It was (section)+offset.  This makes sense if there is
     only one module to look in for a section.  */
  Dwfl_Module *mod = NULL;
  if (dwfl_getmodules (dwfl, &see_one_module, &mod, 0) != 0
      || mod == NULL)
    error (EXIT_FAILURE, 0, gettext ("Section syntax requires"
				     " exactly one module"));

  int nscn = dwfl_module_relocations (mod);
  for (int i = 0; i < nscn; ++i)
    {
      GElf_Word shndx;
      const char *scn = dwfl_module_relocation_info (mod, i, &shndx);
      if (unlikely (scn == NULL))
	break;
      if (!strcmp (scn, name))
	{
	  /* Found the section.  */
	  GElf_Shdr shdr_mem;
	  GElf_Addr shdr_bias;
	  GElf_Shdr *shdr = gelf_getshdr
	    (elf_getscn (dwfl_module_getelf (mod, &shdr_bias), shndx),
	     &shdr_mem);
	  if (unlikely (shdr == NULL))
	    break;

	  if (*addr >= shdr->sh_size)
	    error (0, 0,
		   gettext ("offset %#" PRIxMAX " lies outside"
			    " section '%s'"),
		   *addr, scn);

	  *addr += shdr->sh_addr + shdr_bias;
	  return true;
	}
    }

  return false;
}

static int
handle_address (const char *string, Dwfl *dwfl)
{
  char *endp;
  uintmax_t addr = strtoumax (string, &endp, 0);
  if (endp == string)
    {
      bool parsed = false;
      int i, j;
      char *name = NULL;
      if (sscanf (string, "(%m[^)])%" PRIiMAX "%n", &name, &addr, &i) == 2
	  && string[i] == '\0')
	parsed = adjust_to_section (name, &addr, dwfl);
      switch (sscanf (string, "%m[^-+]%n%" PRIiMAX "%n", &name, &i, &addr, &j))
	{
	default:
	  break;
	case 1:
	  addr = 0;
	  j = i;
	case 2:
	  if (string[j] != '\0')
	    break;

	  /* It was symbol[+offset].  */
	  GElf_Sym sym;
	  void *arg[2] = { name, &sym };
	  (void) dwfl_getmodules (dwfl, &find_symbol, arg, 0);
	  if (arg[0] != NULL)
	    error (0, 0, gettext ("cannot find symbol '%s'"), name);
	  else
	    {
	      if (sym.st_size != 0 && addr >= sym.st_size)
		error (0, 0,
		       gettext ("offset %#" PRIxMAX " lies outside"
				" contents of '%s'"),
		       addr, name);
	      addr += sym.st_value;
	      parsed = true;
	    }
	  break;
	}

      free (name);
      if (!parsed)
	return 1;
    }
  else if (just_section != NULL
	   && !adjust_to_section (just_section, &addr, dwfl))
    return 1;

  Dwfl_Module *mod = dwfl_addrmodule (dwfl, addr);

  if (show_functions)
    {
      /* First determine the function name.  Use the DWARF information if
	 possible.  */
      if (! print_dwarf_function (mod, addr) && !show_symbols)
	puts (dwfl_module_addrname (mod, addr) ?: "??");
    }

  if (show_symbols)
    print_addrsym (mod, addr);

  Dwfl_Line *line = dwfl_module_getsrc (mod, addr);

  const char *src;
  int lineno, linecol;
  if (line != NULL && (src = dwfl_lineinfo (line, &addr, &lineno, &linecol,
					    NULL, NULL)) != NULL)
    {
      const char *comp_dir = "";
      const char *comp_dir_sep = "";

      if (only_basenames)
	src = basename (src);
      else if (use_comp_dir && src[0] != '/')
	{
	  comp_dir = dwfl_line_comp_dir (line);
	  if (comp_dir != NULL)
	    comp_dir_sep = "/";
	}

      if (linecol != 0)
	printf ("%s%s%s:%d:%d",
		comp_dir, comp_dir_sep, src, lineno, linecol);
      else
	printf ("%s%s%s:%d",
		comp_dir, comp_dir_sep, src, lineno);

      if (show_flags)
	{
	  Dwarf_Addr bias;
	  Dwarf_Line *info = dwfl_dwarf_line (line, &bias);
	  assert (info != NULL);

	  inline void show (int (*get) (Dwarf_Line *, bool *),
			    const char *note)
	  {
	    bool flag;
	    if ((*get) (info, &flag) == 0 && flag)
	      fputs (note, stdout);
	  }
	  inline void show_int (int (*get) (Dwarf_Line *, unsigned int *),
				const char *name)
	  {
	    unsigned int val;
	    if ((*get) (info, &val) == 0 && val != 0)
	      printf (" (%s %u)", name, val);
	  }

	  show (&dwarf_linebeginstatement, " (is_stmt)");
	  show (&dwarf_lineblock, " (basic_block)");
	  show (&dwarf_lineprologueend, " (prologue_end)");
	  show (&dwarf_lineepiloguebegin, " (epilogue_begin)");
	  show_int (&dwarf_lineisa, "isa");
	  show_int (&dwarf_linediscriminator, "discriminator");
	}
      putchar ('\n');
    }
  else
    puts ("??:0");

  return 0;
}


#include "debugpred.h"