view main.c @ 953:13916d161ec0

xzcat: remove XZ_(PREALLOC|SINGLE), inline xz_dec_bcj_create Because we only use XZ_DYNALLOC, there's a bunch of dead code. This patch removes the #ifdef's and if()s associated with support for multiple modes. single_call was only used to store the mode; it is no longer needed. A little bit of reorganization was needed to reduce the number of prototypes. Documentation associated with dead code was dropped. There are still some relics of multiple modes in the continued presence of "XZ_DYNALLOC" and xz_mode. Additionally, I inlined xz_dec_bcj_create; it was called once. This loses about 125 lines, mostly comments.
author Isaac Dunham <idunham@lavabit.com>
date Wed, 17 Jul 2013 17:25:07 -0500
parents 812e8c5d026f
children caa05719070f
line wrap: on
line source

/* Toybox infrastructure.
 *
 * Copyright 2006 Rob Landley <rob@landley.net>
 */

#include "toys.h"

// Populate toy_list[].

#undef NEWTOY
#undef OLDTOY
#define NEWTOY(name, opts, flags) {#name, name##_main, opts, flags},
#define OLDTOY(name, oldname, opts, flags) {#name, oldname##_main, opts, flags},

struct toy_list toy_list[] = {
#include "generated/newtoys.h"
};

// global context for this command.

struct toy_context toys;
union global_union this;
char toybuf[4096];

struct toy_list *toy_find(char *name)
{
  int top, bottom, middle;

  // If the name starts with "toybox" accept that as a match.  Otherwise
  // skip the first entry, which is out of order.

  if (!strncmp(name,"toybox",6)) return toy_list;
  bottom = 1;

  // Binary search to find this command.

  top = ARRAY_LEN(toy_list)-1;
  for (;;) {
    int result;

    middle = (top+bottom)/2;
    if (middle<bottom || middle>top) return NULL;
    result = strcmp(name,toy_list[middle].name);
    if (!result) return toy_list+middle;
    if (result<0) top=--middle;
    else bottom = ++middle;
  }
}

// Figure out whether or not anything is using the option parsing logic,
// because the compiler can't figure out whether or not to optimize it away
// on its' own.  NEED_OPTIONS becomes a constant allowing if() to optimize
// stuff out via dead code elimination.

#undef NEWTOY
#undef OLDTOY
#define NEWTOY(name, opts, flags) opts ||
#define OLDTOY(name, oldname, opts, flags) opts ||
static const int NEED_OPTIONS =
#include "generated/newtoys.h"
0;  // Ends the opts || opts || opts...

// Setup toybox global state for this command.

void toy_init(struct toy_list *which, char *argv[])
{
  // Drop permissions for non-suid commands.

  if (CFG_TOYBOX_SUID) {
    uid_t uid = getuid(), euid = geteuid();

    if (!(which->flags & TOYFLAG_STAYROOT)) {
      if (uid != euid) xsetuid(euid=uid);
    } else if (CFG_TOYBOX_DEBUG && uid && which != toy_list)
      error_msg("Not installed suid root");

    if ((which->flags & TOYFLAG_NEEDROOT) && euid) error_exit("Not root");
  }

  // Free old toys contents (to be reentrant), but leave rebound if any

  if (toys.optargs != toys.argv+1) free(toys.optargs);
  memset(&toys, 0, offsetof(struct toy_context, rebound));

  toys.which = which;
  toys.argv = argv;

  if (CFG_TOYBOX_HELP_DASHDASH && argv[1] && !strcmp(argv[1], "--help")) {
    show_help();
    xexit();
  }

  if (NEED_OPTIONS && which->options) get_optflags();
  else {
    toys.optargs = argv+1;
    for (toys.optc=0; toys.optargs[toys.optc]; toys.optc++);
  }
  toys.old_umask = umask(0);
  if (!(which->flags & TOYFLAG_UMASK)) umask(toys.old_umask);
}

// Like exec() but runs an internal toybox command instead of another file.
// Only returns if it can't find the command, otherwise exit() when done.
void toy_exec(char *argv[])
{
  struct toy_list *which;

  if (!(which = toy_find(argv[0]))) return;
  toy_init(which, argv);
  toys.which->toy_main();
  if (fflush(NULL) || ferror(stdout)) perror_exit("write");
  xexit();
}

// Multiplexer command, first argument is command to run, rest are args to that.
// If first argument starts with - output list of command install paths.

void toybox_main(void)
{
  static char *toy_paths[]={"usr/","bin/","sbin/",0};
  int i, len = 0;

  toys.which = toy_list;
  if (toys.argv[1]) {
    if (CFG_TOYBOX_HELP_DASHDASH && !strcmp(toys.argv[1], "--help")) {
      if (toys.argv[2]) toys.which = toy_find(toys.argv[2]);
      if (toys.which) {
        show_help();
        return;
      }
    } else {
      toy_exec(toys.argv+1);
      if (toys.argv[1][0] == '-') goto list;
    }
    
    error_exit("Unknown command %s",toys.argv[1]);
  }

list:
  // Output list of command.
  for (i=1; i<ARRAY_LEN(toy_list); i++) {
    int fl = toy_list[i].flags;
    if (fl & TOYMASK_LOCATION) {
      if (toys.argv[1]) {
        int j;
        for (j=0; toy_paths[j]; j++)
          if (fl & (1<<j)) len += printf("%s", toy_paths[j]);
      }
      len += printf("%s ",toy_list[i].name);
      if (len>65) {
        xputc('\n');
        len=0;
      }
    }
  }
  xputc('\n');
}

int main(int argc, char *argv[])
{
  if (CFG_TOYBOX_I18N) setlocale(LC_ALL, "");

  // Trim path off of command name
  *argv = basename(*argv);

  // Call the multiplexer, adjusting this argv[] to be its' argv[1].
  // (It will adjust it back before calling toy_exec().)
  toys.argv = argv-1;
  toybox_main();
  return 0;
}