view main.c @ 1278:324306321d82 draft

Initial cleanup of last: mostly whitespace, move no record test to start of loop, don't bother to stat an empty file to report when an empty log was created (just report current time).
author Rob Landley <rob@landley.net>
date Sat, 10 May 2014 13:20:03 -0500
parents 1f4a56212c83
children 313980d3d78c
line wrap: on
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/* 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], libbuf[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...

// Subset of init needed by singlemain
static void toy_singleinit(struct toy_list *which, char *argv[])
{
  toys.which = which;
  toys.argv = argv;

  if (CFG_TOYBOX_HELP_DASHDASH && argv[1] && !strcmp(argv[1], "--help")) {
    if (toys.which == toy_list && toys.argv[2])
      if (!(toys.which = toy_find(toys.argv[2]))) return;
    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);
}

// 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)
        if (!setuid(euid=uid)) perror_exit("setuid"); // drop root
    } 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));

  // Subset of init needed by singlemain.
  toy_singleinit(which, argv);
}

// 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);
  if (toys.which) 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]) {
    toys.optc = 0;
    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, "");

  toys.toycount = ARRAY_LEN(toy_list);

  if (CFG_TOYBOX) {
    // 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();
  } else {
    // a single toybox command built standalone with no multiplexer
    toy_singleinit(toy_list, argv);
    toy_list->toy_main();
    if (fflush(NULL) || ferror(stdout)) perror_exit("write");
  }

  return toys.exitval;
}