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/* Copyright (C) 2002 by Red Hat, Incorporated. All rights reserved.
*
* Permission to use, copy, modify, and distribute this software
* is freely granted, provided that this notice is preserved.
*/
#ifndef _NO_WORDEXP
#include <sys/param.h>
#include <sys/stat.h>
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <glob.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/wait.h>
#include <wordexp.h>
#define MAXLINELEN 500
/* Note: This implementation of wordexp requires a version of bash
that supports the --wordexp and --protected arguments to be present
on the system. It does not support the WRDE_UNDEF flag. */
int
wordexp(const char *words, wordexp_t *pwordexp, int flags)
{
FILE *f = NULL;
FILE *f_err = NULL;
char tmp[MAXLINELEN];
int i = 0;
int offs = 0;
char *iter;
pid_t pid;
int num_words = 0;
int num_bytes = 0;
int fd[2];
int fd_err[2];
int err = WRDE_NOSPACE;
char **wordv;
char *ewords = NULL;
char *eword;
if (pwordexp == NULL)
{
return WRDE_NOSPACE;
}
if (flags & WRDE_REUSE)
wordfree(pwordexp);
if ((flags & WRDE_APPEND) == 0)
{
pwordexp->we_wordc = 0;
pwordexp->we_wordv = NULL;
}
if (flags & WRDE_DOOFFS)
{
offs = pwordexp->we_offs;
wordv = (char **)realloc(pwordexp->we_wordv, (pwordexp->we_wordc + offs + 1) * sizeof(char *));
if (!wordv)
return err;
pwordexp->we_wordv = wordv;
for (i = 0; i < offs; i++)
pwordexp->we_wordv[i] = NULL;
}
if (pipe(fd))
return err;
if (pipe(fd_err))
{
close(fd[0]);
close(fd[1]);
return err;
}
pid = fork();
if (pid == -1)
{
/* In "parent" process, but fork failed */
close(fd_err[0]);
close(fd_err[1]);
close(fd[0]);
close(fd[1]);
return err;
}
else if (pid > 0)
{
/* In parent process. */
/* Close write end of parent's pipe. */
close(fd[1]);
close(fd_err[1]);
/* f_err is the standard error from the shell command. */
if (!(f_err = fdopen(fd_err[0], "r")))
goto cleanup;
/* Check for errors. */
if (fgets(tmp, MAXLINELEN, f_err))
{
if (strstr(tmp, "EOF"))
err = WRDE_SYNTAX;
else if (strstr(tmp, "`\n'") || strstr(tmp, "`|'")
|| strstr(tmp, "`&'") || strstr(tmp, "`;'")
|| strstr(tmp, "`<'") || strstr(tmp, "`>'")
|| strstr(tmp, "`('") || strstr(tmp, "`)'")
|| strstr(tmp, "`{'") || strstr(tmp, "`}'"))
err = WRDE_BADCHAR;
else if (strstr(tmp, "command substitution"))
err = WRDE_CMDSUB;
else
err = WRDE_SYNTAX;
if (flags & WRDE_SHOWERR)
{
fprintf(stderr, tmp);
while(fgets(tmp, MAXLINELEN, f_err))
fprintf(stderr, tmp);
}
goto cleanup;
}
/* f is the standard output from the shell command. */
if (!(f = fdopen(fd[0], "r")))
goto cleanup;
/* Get number of words expanded by shell. */
if (!fgets(tmp, MAXLINELEN, f))
goto cleanup;
if((iter = strchr(tmp, '\n')))
*iter = '\0';
num_words = atoi(tmp);
wordv = (char **)realloc(pwordexp->we_wordv,
(pwordexp->we_wordc + num_words + offs + 1) * sizeof(char *));
if (!wordv)
goto cleanup;
pwordexp->we_wordv = wordv;
/* Get number of bytes required for storage of all num_words words. */
if (!fgets(tmp, MAXLINELEN, f))
goto cleanup;
if((iter = strchr(tmp, '\n')))
*iter = '\0';
num_bytes = atoi(tmp);
/* Get expansion from the shell output. */
if (!(ewords = (char *)malloc(num_bytes + num_words + 1)))
goto cleanup;
if (!fread(ewords, 1, num_bytes + num_words, f))
goto cleanup;
ewords[num_bytes + num_words] = 0;
/* Store each entry in pwordexp's we_wordv vector. */
eword = ewords;
for(i = 0; i < num_words; i++)
{
if (eword && (iter = strchr(eword, '\n')))
*iter = '\0';
if (!eword ||
!(pwordexp->we_wordv[pwordexp->we_wordc + offs + i] = strdup(eword)))
{
pwordexp->we_wordv[pwordexp->we_wordc + offs + i] = NULL;
pwordexp->we_wordc += i;
goto cleanup;
}
eword = iter ? iter + 1 : iter;
}
pwordexp->we_wordv[pwordexp->we_wordc + offs + i] = NULL;
pwordexp->we_wordc += num_words;
err = WRDE_SUCCESS;
cleanup:
free(ewords);
if (f)
fclose(f);
else
close(fd[0]);
if (f_err)
fclose(f_err);
else
close(fd_err[0]);
/* Wait for child to finish. */
waitpid (pid, NULL, 0);
return err;
}
else
{
/* In child process. */
/* Close read end of child's pipe. */
close(fd[0]);
close(fd_err[0]);
/* Pipe standard output to parent process via fd. */
if (fd[1] != STDOUT_FILENO)
{
if (dup2(fd[1], STDOUT_FILENO) == -1)
_exit(EXIT_FAILURE);
/* fd[1] no longer required. */
close(fd[1]);
}
/* Pipe standard error to parent process via fd_err. */
if (fd_err[1] != STDERR_FILENO)
{
if (dup2(fd_err[1], STDERR_FILENO) == -1)
_exit(EXIT_FAILURE);
/* fd_err[1] no longer required. */
close(fd_err[1]);
}
if (flags & WRDE_NOCMD)
execl("/bin/bash", "bash", "--protected", "--wordexp", words, (char *)0);
else
execl("/bin/bash", "bash", "--wordexp", words, (char *)0);
_exit(EXIT_FAILURE);
}
return WRDE_SUCCESS;
}
#endif /* !_NO_WORDEXP */
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