/* POSIX.2 wordexp implementation.
Copyright (C) 1997-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Tim Waugh <tim@cyberelk.demon.co.uk>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <fnmatch.h>
#include <glob.h>
#include <libintl.h>
#include <paths.h>
#include <pwd.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <wchar.h>
#include <wordexp.h>
#include <kernel-features.h>
#include <scratch_buffer.h>
#include <libc-lock.h>
#include <_itoa.h>
/* Undefine the following line for the production version. */
/* #define NDEBUG 1 */
#include <assert.h>
/* Get some device information. */
#include <device-nrs.h>
/*
* This is a recursive-descent-style word expansion routine.
*/
/* These variables are defined and initialized in the startup code. */
extern int __libc_argc attribute_hidden;
extern char **__libc_argv attribute_hidden;
/* Some forward declarations */
static int parse_dollars (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset, int flags,
wordexp_t *pwordexp, const char *ifs,
const char *ifs_white, int quoted);
static int parse_backtick (char **word, size_t *word_length,
size_t *max_length, const char *words,
size_t *offset, int flags, wordexp_t *pwordexp,
const char *ifs, const char *ifs_white);
static int parse_dquote (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset, int flags,
wordexp_t *pwordexp, const char *ifs,
const char *ifs_white);
static int eval_expr (char *expr, long int *result);
/* The w_*() functions manipulate word lists. */
#define W_CHUNK (100)
/* Result of w_newword will be ignored if it's the last word. */
static inline char *
w_newword (size_t *actlen, size_t *maxlen)
{
*actlen = *maxlen = 0;
return NULL;
}
static char *
w_addchar (char *buffer, size_t *actlen, size_t *maxlen, char ch)
/* (lengths exclude trailing zero) */
{
/* Add a character to the buffer, allocating room for it if needed. */
if (*actlen == *maxlen)
{
char *old_buffer = buffer;
assert (buffer == NULL || *maxlen != 0);
*maxlen += W_CHUNK;
buffer = (char *) realloc (buffer, 1 + *maxlen);
if (buffer == NULL)
free (old_buffer);
}
if (buffer != NULL)
{
buffer[*actlen] = ch;
buffer[++(*actlen)] = '\0';
}
return buffer;
}
static char *
w_addmem (char *buffer, size_t *actlen, size_t *maxlen, const char *str,
size_t len)
{
/* Add a string to the buffer, allocating room for it if needed.
*/
if (*actlen + len > *maxlen)
{
char *old_buffer = buffer;
assert (buffer == NULL || *maxlen != 0);
*maxlen += MAX (2 * len, W_CHUNK);
buffer = realloc (old_buffer, 1 + *maxlen);
if (buffer == NULL)
free (old_buffer);
}
if (buffer != NULL)
{
*((char *) __mempcpy (&buffer[*actlen], str, len)) = '\0';
*actlen += len;
}
return buffer;
}
static char *
w_addstr (char *buffer, size_t *actlen, size_t *maxlen, const char *str)
/* (lengths exclude trailing zero) */
{
/* Add a string to the buffer, allocating room for it if needed.
*/
size_t len;
assert (str != NULL); /* w_addstr only called from this file */
len = strlen (str);
return w_addmem (buffer, actlen, maxlen, str, len);
}
static int
w_addword (wordexp_t *pwordexp, char *word)
{
/* Add a word to the wordlist */
size_t num_p;
char **new_wordv;
bool allocated = false;
/* Internally, NULL acts like "". Convert NULLs to "" before
* the caller sees them.
*/
if (word == NULL)
{
word = __strdup ("");
if (word == NULL)
goto no_space;
allocated = true;
}
num_p = 2 + pwordexp->we_wordc + pwordexp->we_offs;
new_wordv = realloc (pwordexp->we_wordv, sizeof (char *) * num_p);
if (new_wordv != NULL)
{
pwordexp->we_wordv = new_wordv;
pwordexp->we_wordv[pwordexp->we_offs + pwordexp->we_wordc++] = word;
pwordexp->we_wordv[pwordexp->we_offs + pwordexp->we_wordc] = NULL;
return 0;
}
if (allocated)
free (word);
no_space:
return WRDE_NOSPACE;
}
/* The parse_*() functions should leave *offset being the offset in 'words'
* to the last character processed.
*/
static int
parse_backslash (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset)
{
/* We are poised _at_ a backslash, not in quotes */
switch (words[1 + *offset])
{
case 0:
/* Backslash is last character of input words */
return WRDE_SYNTAX;
case '\n':
++(*offset);
break;
default:
*word = w_addchar (*word, word_length, max_length, words[1 + *offset]);
if (*word == NULL)
return WRDE_NOSPACE;
++(*offset);
break;
}
return 0;
}
static int
parse_qtd_backslash (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset)
{
/* We are poised _at_ a backslash, inside quotes */
switch (words[1 + *offset])
{
case 0:
/* Backslash is last character of input words */
return WRDE_SYNTAX;
case '\n':
++(*offset);
break;
case '$':
case '`':
case '"':
case '\\':
*word = w_addchar (*word, word_length, max_length, words[1 + *offset]);
if (*word == NULL)
return WRDE_NOSPACE;
++(*offset);
break;
default:
*word = w_addchar (*word, word_length, max_length, words[*offset]);
if (*word != NULL)
*word = w_addchar (*word, word_length, max_length, words[1 + *offset]);
if (*word == NULL)
return WRDE_NOSPACE;
++(*offset);
break;
}
return 0;
}
static int
parse_tilde (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset, size_t wordc)
{
/* We are poised _at_ a tilde */
size_t i;
if (*word_length != 0)
{
if (!((*word)[*word_length - 1] == '=' && wordc == 0))
{
if (!((*word)[*word_length - 1] == ':'
&& strchr (*word, '=') && wordc == 0))
{
*word = w_addchar (*word, word_length, max_length, '~');
return *word ? 0 : WRDE_NOSPACE;
}
}
}
for (i = 1 + *offset; words[i]; i++)
{
if (words[i] == ':' || words[i] == '/' || words[i] == ' ' ||
words[i] == '\t' || words[i] == 0 )
break;
if (words[i] == '\\')
{
*word = w_addchar (*word, word_length, max_length, '~');
return *word ? 0 : WRDE_NOSPACE;
}
}
if (i == 1 + *offset)
{
/* Tilde appears on its own */
char* home;
/* POSIX.2 says ~ expands to $HOME and if HOME is unset the
results are unspecified. We do a lookup on the uid if
HOME is unset. */
home = getenv ("HOME");
if (home != NULL)
{
*word = w_addstr (*word, word_length, max_length, home);
if (*word == NULL)
return WRDE_NOSPACE;
}
else
{
struct passwd pwd, *tpwd;
uid_t uid = __getuid ();
int result;
struct scratch_buffer tmpbuf;
scratch_buffer_init (&tmpbuf);
while ((result = __getpwuid_r (uid, &pwd,
tmpbuf.data, tmpbuf.length,
&tpwd)) != 0
&& errno == ERANGE)
if (!scratch_buffer_grow (&tmpbuf))
return WRDE_NOSPACE;
if (result == 0 && tpwd != NULL && pwd.pw_dir != NULL)
{
*word = w_addstr (*word, word_length, max_length, pwd.pw_dir);
if (*word == NULL)
{
scratch_buffer_free (&tmpbuf);
return WRDE_NOSPACE;
}
}
else
{
*word = w_addchar (*word, word_length, max_length, '~');
if (*word == NULL)
{
scratch_buffer_free (&tmpbuf);
return WRDE_NOSPACE;
}
}
scratch_buffer_free (&tmpbuf);
}
}
else
{
/* Look up user name in database to get home directory */
char *user = strndupa (&words[1 + *offset], i - (1 + *offset));
struct passwd pwd, *tpwd;
int result;
struct scratch_buffer tmpbuf;
scratch_buffer_init (&tmpbuf);
while ((result = __getpwnam_r (user, &pwd, tmpbuf.data, tmpbuf.length,
&tpwd)) != 0
&& errno == ERANGE)
if (!scratch_buffer_grow (&tmpbuf))
return WRDE_NOSPACE;
if (result == 0 && tpwd != NULL && pwd.pw_dir)
*word = w_addstr (*word, word_length, max_length, pwd.pw_dir);
else
{
/* (invalid login name) */
*word = w_addchar (*word, word_length, max_length, '~');
if (*word != NULL)
*word = w_addstr (*word, word_length, max_length, user);
}
scratch_buffer_free (&tmpbuf);
*offset = i - 1;
}
return *word ? 0 : WRDE_NOSPACE;
}
static int
do_parse_glob (const char *glob_word, char **word, size_t *word_length,
size_t *max_length, wordexp_t *pwordexp, const char *ifs,
const char *ifs_white)
{
int error;
unsigned int match;
glob_t globbuf;
error = glob (glob_word, GLOB_NOCHECK, NULL, &globbuf);
if (error != 0)
{
/* We can only run into memory problems. */
assert (error == GLOB_NOSPACE);
return WRDE_NOSPACE;
}
if (ifs && !*ifs)
{
/* No field splitting allowed. */
assert (globbuf.gl_pathv[0] != NULL);
*word = w_addstr (*word, word_length, max_length, globbuf.gl_pathv[0]);
for (match = 1; match < globbuf.gl_pathc && *word != NULL; ++match)
{
*word = w_addchar (*word, word_length, max_length, ' ');
if (*word != NULL)
*word = w_addstr (*word, word_length, max_length,
globbuf.gl_pathv[match]);
}
globfree (&globbuf);
return *word ? 0 : WRDE_NOSPACE;
}
assert (ifs == NULL || *ifs != '\0');
if (*word != NULL)
{
free (*word);
*word = w_newword (word_length, max_length);
}
for (match = 0; match < globbuf.gl_pathc; ++match)
{
char *matching_word = __strdup (globbuf.gl_pathv[match]);
if (matching_word == NULL || w_addword (pwordexp, matching_word))
{
globfree (&globbuf);
return WRDE_NOSPACE;
}
}
globfree (&globbuf);
return 0;
}
static int
parse_glob (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset, int flags,
wordexp_t *pwordexp, const char *ifs, const char *ifs_white)
{
/* We are poised just after a '*', a '[' or a '?'. */
int error = WRDE_NOSPACE;
int quoted = 0; /* 1 if singly-quoted, 2 if doubly */
size_t i;
wordexp_t glob_list; /* List of words to glob */
glob_list.we_wordc = 0;
glob_list.we_wordv = NULL;
glob_list.we_offs = 0;
for (; words[*offset] != '\0'; ++*offset)
{
if (strchr (ifs, words[*offset]) != NULL)
/* Reached IFS */
break;
/* Sort out quoting */
if (words[*offset] == '\'')
{
if (quoted == 0)
{
quoted = 1;
continue;
}
else if (quoted == 1)
{
quoted = 0;
continue;
}
}
else if (words[*offset] == '"')
{
if (quoted == 0)
{
quoted = 2;
continue;
}
else if (quoted == 2)
{
quoted = 0;
continue;
}
}
/* Sort out other special characters */
if (quoted != 1 && words[*offset] == '$')
{
error = parse_dollars (word, word_length, max_length, words,
offset, flags, &glob_list, ifs, ifs_white,
quoted == 2);
if (error)
goto tidy_up;
continue;
}
else if (words[*offset] == '\\')
{
if (quoted)
error = parse_qtd_backslash (word, word_length, max_length,
words, offset);
else
error = parse_backslash (word, word_length, max_length,
words, offset);
if (error)
goto tidy_up;
continue;
}
*word = w_addchar (*word, word_length, max_length, words[*offset]);
if (*word == NULL)
goto tidy_up;
}
/* Don't forget to re-parse the character we stopped at. */
--*offset;
/* Glob the words */
error = w_addword (&glob_list, *word);
*word = w_newword (word_length, max_length);
for (i = 0; error == 0 && i < glob_list.we_wordc; i++)
error = do_parse_glob (glob_list.we_wordv[i], word, word_length,
max_length, pwordexp, ifs, ifs_white);
/* Now tidy up */
tidy_up:
wordfree (&glob_list);
return error;
}
static int
parse_squote (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset)
{
/* We are poised just after a single quote */
for (; words[*offset]; ++(*offset))
{
if (words[*offset] != '\'')
{
*word = w_addchar (*word, word_length, max_length, words[*offset]);
if (*word == NULL)
return WRDE_NOSPACE;
}
else return 0;
}
/* Unterminated string */
return WRDE_SYNTAX;
}
/* Functions to evaluate an arithmetic expression */
static int
eval_expr_val (char **expr, long int *result)
{
char *digit;
/* Skip white space */
for (digit = *expr; digit && *digit && isspace (*digit); ++digit);
if (*digit == '(')
{
/* Scan for closing paren */
for (++digit; **expr && **expr != ')'; ++(*expr));
/* Is there one? */
if (!**expr)
return WRDE_SYNTAX;
*(*expr)++ = 0;
if (eval_expr (digit, result))
return WRDE_SYNTAX;
return 0;
}
/* POSIX requires that decimal, octal, and hexadecimal constants are
recognized. Therefore we pass 0 as the third parameter to strtol. */
*result = strtol (digit, expr, 0);
if (digit == *expr)
return WRDE_SYNTAX;
return 0;
}
static int
eval_expr_multdiv (char **expr, long int *result)
{
long int arg;
/* Read a Value */
if (eval_expr_val (expr, result) != 0)
return WRDE_SYNTAX;
while (**expr)
{
/* Skip white space */
for (; *expr && **expr && isspace (**expr); ++(*expr));
if (**expr == '*')
{
++(*expr);
if (eval_expr_val (expr, &arg) != 0)
return WRDE_SYNTAX;
*result *= arg;
}
else if (**expr == '/')
{
++(*expr);
if (eval_expr_val (expr, &arg) != 0)
return WRDE_SYNTAX;
/* Division by zero or integer overflow. */
if (arg == 0 || (arg == -1 && *result == LONG_MIN))
return WRDE_SYNTAX;
*result /= arg;
}
else break;
}
return 0;
}
static int
eval_expr (char *expr, long int *result)
{
long int arg;
/* Read a Multdiv */
if (eval_expr_multdiv (&expr, result) != 0)
return WRDE_SYNTAX;
while (*expr)
{
/* Skip white space */
for (; expr && *expr && isspace (*expr); ++expr);
if (*expr == '+')
{
++expr;
if (eval_expr_multdiv (&expr, &arg) != 0)
return WRDE_SYNTAX;
*result += arg;
}
else if (*expr == '-')
{
++expr;
if (eval_expr_multdiv (&expr, &arg) != 0)
return WRDE_SYNTAX;
*result -= arg;
}
else break;
}
return 0;
}
static int
parse_arith (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset, int flags, int bracket)
{
/* We are poised just after "$((" or "$[" */
int error;
int paren_depth = 1;
size_t expr_length;
size_t expr_maxlen;
char *expr;
expr = w_newword (&expr_length, &expr_maxlen);
for (; words[*offset]; ++(*offset))
{
switch (words[*offset])
{
case '$':
error = parse_dollars (&expr, &expr_length, &expr_maxlen,
words, offset, flags, NULL, NULL, NULL, 1);
/* The ``1'' here is to tell parse_dollars not to
* split the fields.
*/
if (error)
{
free (expr);
return error;
}
break;
case '`':
(*offset)++;
error = parse_backtick (&expr, &expr_length, &expr_maxlen,
words, offset, flags, NULL, NULL, NULL);
/* The first NULL here is to tell parse_backtick not to
* split the fields.
*/
if (error)
{
free (expr);
return error;
}
break;
case '\\':
error = parse_qtd_backslash (&expr, &expr_length, &expr_maxlen,
words, offset);
if (error)
{
free (expr);
return error;
}
/* I think that a backslash within an
* arithmetic expansion is bound to
* cause an error sooner or later anyway though.
*/
break;
case ')':
if (--paren_depth == 0)
{
char result[21]; /* 21 = ceil(log10(2^64)) + 1 */
long int numresult = 0;
long long int convertme;
if (bracket || words[1 + *offset] != ')')
{
free (expr);
return WRDE_SYNTAX;
}
++(*offset);
/* Go - evaluate. */
if (*expr && eval_expr (expr, &numresult) != 0)
{
free (expr);
return WRDE_SYNTAX;
}
if (numresult < 0)
{
convertme = -numresult;
*word = w_addchar (*word, word_length, max_length, '-');
if (!*word)
{
free (expr);
return WRDE_NOSPACE;
}
}
else
convertme = numresult;
result[20] = '\0';
*word = w_addstr (*word, word_length, max_length,
_itoa (convertme, &result[20], 10, 0));
free (expr);
return *word ? 0 : WRDE_NOSPACE;
}
expr = w_addchar (expr, &expr_length, &expr_maxlen, words[*offset]);
if (expr == NULL)
return WRDE_NOSPACE;
break;
case ']':
if (bracket && paren_depth == 1)
{
char result[21]; /* 21 = ceil(log10(2^64)) + 1 */
long int numresult = 0;
/* Go - evaluate. */
if (*expr && eval_expr (expr, &numresult) != 0)
{
free (expr);
return WRDE_SYNTAX;
}
result[20] = '\0';
*word = w_addstr (*word, word_length, max_length,
_itoa_word (numresult, &result[20], 10, 0));
free (expr);
return *word ? 0 : WRDE_NOSPACE;
}
free (expr);
return WRDE_SYNTAX;
case '\n':
case ';':
case '{':
case '}':
free (expr);
return WRDE_BADCHAR;
case '(':
++paren_depth;
/* Fall through. */
default:
expr = w_addchar (expr, &expr_length, &expr_maxlen, words[*offset]);
if (expr == NULL)
return WRDE_NOSPACE;
}
}
/* Premature end */
free (expr);
return WRDE_SYNTAX;
}
/* Function called by child process in exec_comm() */
static inline void
__attribute__ ((always_inline))
exec_comm_child (char *comm, int *fildes, int showerr, int noexec)
{
const char *args[4] = { _PATH_BSHELL, "-c", comm, NULL };
/* Execute the command, or just check syntax? */
if (noexec)
args[1] = "-nc";
/* Redirect output. */
if (__glibc_likely (fildes[1] != STDOUT_FILENO))
{
__dup2 (fildes[1], STDOUT_FILENO);
__close (fildes[1]);
}
else
/* Reset the close-on-exec flag (if necessary). */
__fcntl (fildes[1], F_SETFD, 0);
/* Redirect stderr to /dev/null if we have to. */
if (showerr == 0)
{
struct stat64 st;
int fd;
__close (STDERR_FILENO);
fd = __open (_PATH_DEVNULL, O_WRONLY);
if (fd >= 0 && fd != STDERR_FILENO)
{
__dup2 (fd, STDERR_FILENO);
__close (fd);
}
/* Be paranoid. Check that we actually opened the /dev/null
device. */
if (__builtin_expect (__fxstat64 (_STAT_VER, STDERR_FILENO, &st), 0) != 0
|| __builtin_expect (S_ISCHR (st.st_mode), 1) == 0
#if defined DEV_NULL_MAJOR && defined DEV_NULL_MINOR
|| st.st_rdev != __gnu_dev_makedev (DEV_NULL_MAJOR, DEV_NULL_MINOR)
#endif
)
/* It's not the /dev/null device. Stop right here. The
problem is: how do we stop? We use _exit() with an
hopefully unusual exit code. */
_exit (90);
}
/* Make sure the subshell doesn't field-split on our behalf. */
__unsetenv ("IFS");
__close (fildes[0]);
__execve (_PATH_BSHELL, (char *const *) args, __environ);
/* Bad. What now? */
abort ();
}
/* Function to execute a command and retrieve the results */
/* pwordexp contains NULL if field-splitting is forbidden */
static int
exec_comm (char *comm, char **word, size_t *word_length, size_t *max_length,
int flags, wordexp_t *pwordexp, const char *ifs,
const char *ifs_white)
{
int fildes[2];
#define bufsize 128
int buflen;
int i;
int status = 0;
size_t maxnewlines = 0;
char buffer[bufsize];
pid_t pid;
int noexec = 0;
/* Do nothing if command substitution should not succeed. */
if (flags & WRDE_NOCMD)
return WRDE_CMDSUB;
/* Don't fork() unless necessary */
if (!comm || !*comm)
return 0;
if (__pipe2 (fildes, O_CLOEXEC) < 0)
return WRDE_NOSPACE;
again:
if ((pid = __fork ()) < 0)
{
/* Bad */
__close (fildes[0]);
__close (fildes[1]);
return WRDE_NOSPACE;
}
if (pid == 0)
exec_comm_child (comm, fildes, noexec ? 0 : flags & WRDE_SHOWERR, noexec);
/* Parent */
/* If we are just testing the syntax, only wait. */
if (noexec)
return (TEMP_FAILURE_RETRY (__waitpid (pid, &status, 0)) == pid
&& status != 0) ? WRDE_SYNTAX : 0;
__close (fildes[1]);
fildes[1] = -1;
if (!pwordexp)
/* Quoted - no field splitting */
{
while (1)
{
if ((buflen = TEMP_FAILURE_RETRY (__read (fildes[0], buffer,
bufsize))) < 1)
{
/* If read returned 0 then the process has closed its
stdout. Don't use WNOHANG in that case to avoid busy
looping until the process eventually exits. */
if (TEMP_FAILURE_RETRY (__waitpid (pid, &status,
buflen == 0 ? 0 : WNOHANG))
== 0)
continue;
if ((buflen = TEMP_FAILURE_RETRY (__read (fildes[0], buffer,
bufsize))) < 1)
break;
}
maxnewlines += buflen;
*word = w_addmem (*word, word_length, max_length, buffer, buflen);
if (*word == NULL)
goto no_space;
}
}
else
/* Not quoted - split fields */
{
int copying = 0;
/* 'copying' is:
* 0 when searching for first character in a field not IFS white space
* 1 when copying the text of a field
* 2 when searching for possible non-whitespace IFS
* 3 when searching for non-newline after copying field
*/
while (1)
{
if ((buflen = TEMP_FAILURE_RETRY (__read (fildes[0], buffer,
bufsize))) < 1)
{
/* If read returned 0 then the process has closed its
stdout. Don't use WNOHANG in that case to avoid busy
looping until the process eventually exits. */
if (TEMP_FAILURE_RETRY (__waitpid (pid, &status,
buflen == 0 ? 0 : WNOHANG))
== 0)
continue;
if ((buflen = TEMP_FAILURE_RETRY (__read (fildes[0], buffer,
bufsize))) < 1)
break;
}
for (i = 0; i < buflen; ++i)
{
if (strchr (ifs, buffer[i]) != NULL)
{
/* Current character is IFS */
if (strchr (ifs_white, buffer[i]) == NULL)
{
/* Current character is IFS but not whitespace */
if (copying == 2)
{
/* current character
* |
* V
* eg: text<space><comma><space>moretext
*
* So, strip whitespace IFS (like at the start)
*/
copying = 0;
continue;
}
copying = 0;
/* fall through and delimit field.. */
}
else
{
if (buffer[i] == '\n')
{
/* Current character is (IFS) newline */
/* If copying a field, this is the end of it,
but maybe all that's left is trailing newlines.
So start searching for a non-newline. */
if (copying == 1)
copying = 3;
continue;
}
else
{
/* Current character is IFS white space, but
not a newline */
/* If not either copying a field or searching
for non-newline after a field, ignore it */
if (copying != 1 && copying != 3)
continue;
/* End of field (search for non-ws IFS afterwards) */
copying = 2;
}
}
/* First IFS white space (non-newline), or IFS non-whitespace.
* Delimit the field. Nulls are converted by w_addword. */
if (w_addword (pwordexp, *word) == WRDE_NOSPACE)
goto no_space;
*word = w_newword (word_length, max_length);
maxnewlines = 0;
/* fall back round the loop.. */
}
else
{
/* Not IFS character */
if (copying == 3)
{
/* Nothing but (IFS) newlines since the last field,
so delimit it here before starting new word */
if (w_addword (pwordexp, *word) == WRDE_NOSPACE)
goto no_space;
*word = w_newword (word_length, max_length);
}
copying = 1;
if (buffer[i] == '\n') /* happens if newline not in IFS */
maxnewlines++;
else
maxnewlines = 0;
*word = w_addchar (*word, word_length, max_length,
buffer[i]);
if (*word == NULL)
goto no_space;
}
}
}
}
/* Chop off trailing newlines (required by POSIX.2) */
/* Ensure we don't go back further than the beginning of the
substitution (i.e. remove maxnewlines bytes at most) */
while (maxnewlines-- != 0 &&
*word_length > 0 && (*word)[*word_length - 1] == '\n')
{
(*word)[--*word_length] = '\0';
/* If the last word was entirely newlines, turn it into a new word
* which can be ignored if there's nothing following it. */
if (*word_length == 0)
{
free (*word);
*word = w_newword (word_length, max_length);
break;
}
}
__close (fildes[0]);
fildes[0] = -1;
/* Check for syntax error (re-execute but with "-n" flag) */
if (buflen < 1 && status != 0)
{
noexec = 1;
goto again;
}
return 0;
no_space:
__kill (pid, SIGKILL);
TEMP_FAILURE_RETRY (__waitpid (pid, NULL, 0));
__close (fildes[0]);
return WRDE_NOSPACE;
}
static int
parse_comm (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset, int flags, wordexp_t *pwordexp,
const char *ifs, const char *ifs_white)
{
/* We are poised just after "$(" */
int paren_depth = 1;
int error = 0;
int quoted = 0; /* 1 for singly-quoted, 2 for doubly-quoted */
size_t comm_length;
size_t comm_maxlen;
char *comm = w_newword (&comm_length, &comm_maxlen);
for (; words[*offset]; ++(*offset))
{
switch (words[*offset])
{
case '\'':
if (quoted == 0)
quoted = 1;
else if (quoted == 1)
quoted = 0;
break;
case '"':
if (quoted == 0)
quoted = 2;
else if (quoted == 2)
quoted = 0;
break;
case ')':
if (!quoted && --paren_depth == 0)
{
/* Go -- give script to the shell */
if (comm)
{
#ifdef __libc_ptf_call
/* We do not want the exec_comm call to be cut short
by a thread cancellation since cleanup is very
ugly. Therefore disable cancellation for
now. */
// XXX Ideally we do want the thread being cancelable.
// XXX If demand is there we'll change it.
int state = PTHREAD_CANCEL_ENABLE;
__libc_ptf_call (__pthread_setcancelstate,
(PTHREAD_CANCEL_DISABLE, &state), 0);
#endif
error = exec_comm (comm, word, word_length, max_length,
flags, pwordexp, ifs, ifs_white);
#ifdef __libc_ptf_call
__libc_ptf_call (__pthread_setcancelstate,
(state, NULL), 0);
#endif
free (comm);
}
return error;
}
/* This is just part of the script */
break;
case '(':
if (!quoted)
++paren_depth;
}
comm = w_addchar (comm, &comm_length, &comm_maxlen, words[*offset]);
if (comm == NULL)
return WRDE_NOSPACE;
}
/* Premature end. */
free (comm);
return WRDE_SYNTAX;
}
#define CHAR_IN_SET(ch, char_set) \
(memchr (char_set "", ch, sizeof (char_set) - 1) != NULL)
static int
parse_param (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset, int flags, wordexp_t *pwordexp,
const char *ifs, const char *ifs_white, int quoted)
{
/* We are poised just after "$" */
enum action
{
ACT_NONE,
ACT_RP_SHORT_LEFT = '#',
ACT_RP_LONG_LEFT = 'L',
ACT_RP_SHORT_RIGHT = '%',
ACT_RP_LONG_RIGHT = 'R',
ACT_NULL_ERROR = '?',
ACT_NULL_SUBST = '-',
ACT_NONNULL_SUBST = '+',
ACT_NULL_ASSIGN = '='
};
size_t env_length;
size_t env_maxlen;
size_t pat_length;
size_t pat_maxlen;
size_t start = *offset;
char *env;
char *pattern;
char *value = NULL;
enum action action = ACT_NONE;
int depth = 0;
int colon_seen = 0;
int seen_hash = 0;
int free_value = 0;
int pattern_is_quoted = 0; /* 1 for singly-quoted, 2 for doubly-quoted */
int error;
int special = 0;
char buffer[21];
int brace = words[*offset] == '{';
env = w_newword (&env_length, &env_maxlen);
pattern = w_newword (&pat_length, &pat_maxlen);
if (brace)
++*offset;
/* First collect the parameter name. */
if (words[*offset] == '#')
{
seen_hash = 1;
if (!brace)
goto envsubst;
++*offset;
}
if (isalpha (words[*offset]) || words[*offset] == '_')
{
/* Normal parameter name. */
do
{
env = w_addchar (env, &env_length, &env_maxlen,
words[*offset]);
if (env == NULL)
goto no_space;
}
while (isalnum (words[++*offset]) || words[*offset] == '_');
}
else if (isdigit (words[*offset]))
{
/* Numeric parameter name. */
special = 1;
do
{
env = w_addchar (env, &env_length, &env_maxlen,
words[*offset]);
if (env == NULL)
goto no_space;
if (!brace)
goto envsubst;
}
while (isdigit(words[++*offset]));
}
else if (CHAR_IN_SET (words[*offset], "*@$"))
{
/* Special parameter. */
special = 1;
env = w_addchar (env, &env_length, &env_maxlen,
words[*offset]);
if (env == NULL)
goto no_space;
++*offset;
}
else
{
if (brace)
goto syntax;
}
if (brace)
{
/* Check for special action to be applied to the value. */
switch (words[*offset])
{
case '}':
/* Evaluate. */
goto envsubst;
case '#':
action = ACT_RP_SHORT_LEFT;
if (words[1 + *offset] == '#')
{
++*offset;
action = ACT_RP_LONG_LEFT;
}
break;
case '%':
action = ACT_RP_SHORT_RIGHT;
if (words[1 + *offset] == '%')
{
++*offset;
action = ACT_RP_LONG_RIGHT;
}
break;
case ':':
if (!CHAR_IN_SET (words[1 + *offset], "-=?+"))
goto syntax;
colon_seen = 1;
action = words[++*offset];
break;
case '-':
case '=':
case '?':
case '+':
action = words[*offset];
break;
default:
goto syntax;
}
/* Now collect the pattern, but don't expand it yet. */
++*offset;
for (; words[*offset]; ++(*offset))
{
switch (words[*offset])
{
case '{':
if (!pattern_is_quoted)
++depth;
break;
case '}':
if (!pattern_is_quoted)
{
if (depth == 0)
goto envsubst;
--depth;
}
break;
case '\\':
if (pattern_is_quoted)
/* Quoted; treat as normal character. */
break;
/* Otherwise, it's an escape: next character is literal. */
if (words[++*offset] == '\0')
goto syntax;
pattern = w_addchar (pattern, &pat_length, &pat_maxlen, '\\');
if (pattern == NULL)
goto no_space;
break;
case '\'':
if (pattern_is_quoted == 0)
pattern_is_quoted = 1;
else if (pattern_is_quoted == 1)
pattern_is_quoted = 0;
break;
case '"':
if (pattern_is_quoted == 0)
pattern_is_quoted = 2;
else if (pattern_is_quoted == 2)
pattern_is_quoted = 0;
break;
}
pattern = w_addchar (pattern, &pat_length, &pat_maxlen,
words[*offset]);
if (pattern == NULL)
goto no_space;
}
}
/* End of input string -- remember to reparse the character that we
* stopped at. */
--(*offset);
envsubst:
if (words[start] == '{' && words[*offset] != '}')
goto syntax;
if (env == NULL)
{
if (seen_hash)
{
/* $# expands to the number of positional parameters */
buffer[20] = '\0';
value = _itoa_word (__libc_argc - 1, &buffer[20], 10, 0);
seen_hash = 0;
}
else
{
/* Just $ on its own */
*offset = start - 1;
*word = w_addchar (*word, word_length, max_length, '$');
return *word ? 0 : WRDE_NOSPACE;
}
}
/* Is it a numeric parameter? */
else if (isdigit (env[0]))
{
int n = atoi (env);
if (n >= __libc_argc)
/* Substitute NULL. */
value = NULL;
else
/* Replace with appropriate positional parameter. */
value = __libc_argv[n];
}
/* Is it a special parameter? */
else if (special)
{
/* Is it `$$'? */
if (*env == '$')
{
buffer[20] = '\0';
value = _itoa_word (__getpid (), &buffer[20], 10, 0);
}
/* Is it `${#*}' or `${#@}'? */
else if ((*env == '*' || *env == '@') && seen_hash)
{
buffer[20] = '\0';
value = _itoa_word (__libc_argc > 0 ? __libc_argc - 1 : 0,
&buffer[20], 10, 0);
*word = w_addstr (*word, word_length, max_length, value);
free (env);
free (pattern);
return *word ? 0 : WRDE_NOSPACE;
}
/* Is it `$*' or `$@' (unquoted) ? */
else if (*env == '*' || (*env == '@' && !quoted))
{
size_t plist_len = 0;
int p;
char *end;
/* Build up value parameter by parameter (copy them) */
for (p = 1; __libc_argv[p]; ++p)
plist_len += strlen (__libc_argv[p]) + 1; /* for space */
value = malloc (plist_len);
if (value == NULL)
goto no_space;
end = value;
*end = 0;
for (p = 1; __libc_argv[p]; ++p)
{
if (p > 1)
*end++ = ' ';
end = __stpcpy (end, __libc_argv[p]);
}
free_value = 1;
}
else
{
/* Must be a quoted `$@' */
assert (*env == '@' && quoted);
/* Each parameter is a separate word ("$@") */
if (__libc_argc == 2)
value = __libc_argv[1];
else if (__libc_argc > 2)
{
int p;
/* Append first parameter to current word. */
value = w_addstr (*word, word_length, max_length,
__libc_argv[1]);
if (value == NULL || w_addword (pwordexp, value))
goto no_space;
for (p = 2; __libc_argv[p + 1]; p++)
{
char *newword = __strdup (__libc_argv[p]);
if (newword == NULL || w_addword (pwordexp, newword))
goto no_space;
}
/* Start a new word with the last parameter. */
*word = w_newword (word_length, max_length);
value = __libc_argv[p];
}
else
{
free (env);
free (pattern);
return 0;
}
}
}
else
value = getenv (env);
if (value == NULL && (flags & WRDE_UNDEF))
{
/* Variable not defined. */
error = WRDE_BADVAL;
goto do_error;
}
if (action != ACT_NONE)
{
int expand_pattern = 0;
/* First, find out if we need to expand pattern (i.e. if we will
* use it). */
switch (action)
{
case ACT_RP_SHORT_LEFT:
case ACT_RP_LONG_LEFT:
case ACT_RP_SHORT_RIGHT:
case ACT_RP_LONG_RIGHT:
/* Always expand for these. */
expand_pattern = 1;
break;
case ACT_NULL_ERROR:
case ACT_NULL_SUBST:
case ACT_NULL_ASSIGN:
if (!value || (!*value && colon_seen))
/* If param is unset, or set but null and a colon has been seen,
the expansion of the pattern will be needed. */
expand_pattern = 1;
break;
case ACT_NONNULL_SUBST:
/* Expansion of word will be needed if parameter is set and not null,
or set null but no colon has been seen. */
if (value && (*value || !colon_seen))
expand_pattern = 1;
break;
default:
assert (! "Unrecognised action!");
}
if (expand_pattern)
{
/* We need to perform tilde expansion, parameter expansion,
command substitution, and arithmetic expansion. We also
have to be a bit careful with wildcard characters, as
pattern might be given to fnmatch soon. To do this, we
convert quotes to escapes. */
char *expanded;
size_t exp_len;
size_t exp_maxl;
char *p;
int quoted = 0; /* 1: single quotes; 2: double */
expanded = w_newword (&exp_len, &exp_maxl);
for (p = pattern; p && *p; p++)
{
size_t offset;
switch (*p)
{
case '"':
if (quoted == 2)
quoted = 0;
else if (quoted == 0)
quoted = 2;
else break;
continue;
case '\'':
if (quoted == 1)
quoted = 0;
else if (quoted == 0)
quoted = 1;
else break;
continue;
case '*':
case '?':
if (quoted)
{
/* Convert quoted wildchar to escaped wildchar. */
expanded = w_addchar (expanded, &exp_len,
&exp_maxl, '\\');
if (expanded == NULL)
goto no_space;
}
break;
case '$':
offset = 0;
error = parse_dollars (&expanded, &exp_len, &exp_maxl, p,
&offset, flags, NULL, NULL, NULL, 1);
if (error)
{
if (free_value)
free (value);
free (expanded);
goto do_error;
}
p += offset;
continue;
case '~':
if (quoted || exp_len)
break;
offset = 0;
error = parse_tilde (&expanded, &exp_len, &exp_maxl, p,
&offset, 0);
if (error)
{
if (free_value)
free (value);
free (expanded);
goto do_error;
}
p += offset;
continue;
case '\\':
expanded = w_addchar (expanded, &exp_len, &exp_maxl, '\\');
++p;
assert (*p); /* checked when extracted initially */
if (expanded == NULL)
goto no_space;
}
expanded = w_addchar (expanded, &exp_len, &exp_maxl, *p);
if (expanded == NULL)
goto no_space;
}
free (pattern);
pattern = expanded;
}
switch (action)
{
case ACT_RP_SHORT_LEFT:
case ACT_RP_LONG_LEFT:
case ACT_RP_SHORT_RIGHT:
case ACT_RP_LONG_RIGHT:
{
char *p;
char c;
char *end;
if (value == NULL || pattern == NULL || *pattern == '\0')
break;
end = value + strlen (value);
switch (action)
{
case ACT_RP_SHORT_LEFT:
for (p = value; p <= end; ++p)
{
c = *p;
*p = '\0';
if (fnmatch (pattern, value, 0) != FNM_NOMATCH)
{
*p = c;
if (free_value)
{
char *newval = __strdup (p);
if (newval == NULL)
{
free (value);
goto no_space;
}
free (value);
value = newval;
}
else
value = p;
break;
}
*p = c;
}
break;
case ACT_RP_LONG_LEFT:
for (p = end; p >= value; --p)
{
c = *p;
*p = '\0';
if (fnmatch (pattern, value, 0) != FNM_NOMATCH)
{
*p = c;
if (free_value)
{
char *newval = __strdup (p);
if (newval == NULL)
{
free (value);
goto no_space;
}
free (value);
value = newval;
}
else
value = p;
break;
}
*p = c;
}
break;
case ACT_RP_SHORT_RIGHT:
for (p = end; p >= value; --p)
{
if (fnmatch (pattern, p, 0) != FNM_NOMATCH)
{
char *newval;
newval = malloc (p - value + 1);
if (newval == NULL)
{
if (free_value)
free (value);
goto no_space;
}
*(char *) __mempcpy (newval, value, p - value) = '\0';
if (free_value)
free (value);
value = newval;
free_value = 1;
break;
}
}
break;
case ACT_RP_LONG_RIGHT:
for (p = value; p <= end; ++p)
{
if (fnmatch (pattern, p, 0) != FNM_NOMATCH)
{
char *newval;
newval = malloc (p - value + 1);
if (newval == NULL)
{
if (free_value)
free (value);
goto no_space;
}
*(char *) __mempcpy (newval, value, p - value) = '\0';
if (free_value)
free (value);
value = newval;
free_value = 1;
break;
}
}
break;
default:
break;
}
break;
}
case ACT_NULL_ERROR:
if (value && *value)
/* Substitute parameter */
break;
error = 0;
if (!colon_seen && value)
/* Substitute NULL */
;
else
{
const char *str = pattern;
if (str[0] == '\0')
str = _("parameter null or not set");
__fxprintf (NULL, "%s: %s\n", env, str);
}
if (free_value)
free (value);
goto do_error;
case ACT_NULL_SUBST:
if (value && *value)
/* Substitute parameter */
break;
if (free_value)
free (value);
if (!colon_seen && value)
/* Substitute NULL */
goto success;
value = pattern ? __strdup (pattern) : pattern;
free_value = 1;
if (pattern && !value)
goto no_space;
break;
case ACT_NONNULL_SUBST:
if (value && (*value || !colon_seen))
{
if (free_value)
free (value);
value = pattern ? __strdup (pattern) : pattern;
free_value = 1;
if (pattern && !value)
goto no_space;
break;
}
/* Substitute NULL */
if (free_value)
free (value);
goto success;
case ACT_NULL_ASSIGN:
if (value && *value)
/* Substitute parameter */
break;
if (!colon_seen && value)
{
/* Substitute NULL */
if (free_value)
free (value);
goto success;
}
if (free_value)
free (value);
value = pattern ? __strdup (pattern) : pattern;
free_value = 1;
if (pattern && !value)
goto no_space;
__setenv (env, value ?: "", 1);
break;
default:
assert (! "Unrecognised action!");
}
}
free (env);
env = NULL;
free (pattern);
pattern = NULL;
if (seen_hash)
{
char param_length[21];
param_length[20] = '\0';
*word = w_addstr (*word, word_length, max_length,
_itoa_word (value ? strlen (value) : 0,
¶m_length[20], 10, 0));
if (free_value)
{
assert (value != NULL);
free (value);
}
return *word ? 0 : WRDE_NOSPACE;
}
if (value == NULL)
return 0;
if (quoted || !pwordexp)
{
/* Quoted - no field split */
*word = w_addstr (*word, word_length, max_length, value);
if (free_value)
free (value);
return *word ? 0 : WRDE_NOSPACE;
}
else
{
/* Need to field-split */
char *value_copy = __strdup (value); /* Don't modify value */
char *field_begin = value_copy;
int seen_nonws_ifs = 0;
if (free_value)
free (value);
if (value_copy == NULL)
goto no_space;
do
{
char *field_end = field_begin;
char *next_field;
/* If this isn't the first field, start a new word */
if (field_begin != value_copy)
{
if (w_addword (pwordexp, *word) == WRDE_NOSPACE)
{
free (value_copy);
goto no_space;
}
*word = w_newword (word_length, max_length);
}
/* Skip IFS whitespace before the field */
field_begin += strspn (field_begin, ifs_white);
if (!seen_nonws_ifs && *field_begin == 0)
/* Nothing but whitespace */
break;
/* Search for the end of the field */
field_end = field_begin + strcspn (field_begin, ifs);
/* Set up pointer to the character after end of field and
skip whitespace IFS after it. */
next_field = field_end + strspn (field_end, ifs_white);
/* Skip at most one non-whitespace IFS character after the field */
seen_nonws_ifs = 0;
if (*next_field && strchr (ifs, *next_field))
{
seen_nonws_ifs = 1;
next_field++;
}
/* Null-terminate it */
*field_end = 0;
/* Tag a copy onto the current word */
*word = w_addstr (*word, word_length, max_length, field_begin);
if (*word == NULL && *field_begin != '\0')
{
free (value_copy);
goto no_space;
}
field_begin = next_field;
}
while (seen_nonws_ifs || *field_begin);
free (value_copy);
}
return 0;
success:
error = 0;
goto do_error;
no_space:
error = WRDE_NOSPACE;
goto do_error;
syntax:
error = WRDE_SYNTAX;
do_error:
free (env);
free (pattern);
return error;
}
#undef CHAR_IN_SET
static int
parse_dollars (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset, int flags,
wordexp_t *pwordexp, const char *ifs, const char *ifs_white,
int quoted)
{
/* We are poised _at_ "$" */
switch (words[1 + *offset])
{
case '"':
case '\'':
case 0:
*word = w_addchar (*word, word_length, max_length, '$');
return *word ? 0 : WRDE_NOSPACE;
case '(':
if (words[2 + *offset] == '(')
{
/* Differentiate between $((1+3)) and $((echo);(ls)) */
int i = 3 + *offset;
int depth = 0;
while (words[i] && !(depth == 0 && words[i] == ')'))
{
if (words[i] == '(')
++depth;
else if (words[i] == ')')
--depth;
++i;
}
if (words[i] == ')' && words[i + 1] == ')')
{
(*offset) += 3;
/* Call parse_arith -- 0 is for "no brackets" */
return parse_arith (word, word_length, max_length, words, offset,
flags, 0);
}
}
(*offset) += 2;
return parse_comm (word, word_length, max_length, words, offset, flags,
quoted? NULL : pwordexp, ifs, ifs_white);
case '[':
(*offset) += 2;
/* Call parse_arith -- 1 is for "brackets" */
return parse_arith (word, word_length, max_length, words, offset, flags,
1);
case '{':
default:
++(*offset); /* parse_param needs to know if "{" is there */
return parse_param (word, word_length, max_length, words, offset, flags,
pwordexp, ifs, ifs_white, quoted);
}
}
static int
parse_backtick (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset, int flags,
wordexp_t *pwordexp, const char *ifs, const char *ifs_white)
{
/* We are poised just after "`" */
int error;
int squoting = 0;
size_t comm_length;
size_t comm_maxlen;
char *comm = w_newword (&comm_length, &comm_maxlen);
for (; words[*offset]; ++(*offset))
{
switch (words[*offset])
{
case '`':
/* Go -- give the script to the shell */
error = exec_comm (comm, word, word_length, max_length, flags,
pwordexp, ifs, ifs_white);
free (comm);
return error;
case '\\':
if (squoting)
{
error = parse_qtd_backslash (&comm, &comm_length, &comm_maxlen,
words, offset);
if (error)
{
free (comm);
return error;
}
break;
}
error = parse_backslash (&comm, &comm_length, &comm_maxlen, words,
offset);
if (error)
{
free (comm);
return error;
}
break;
case '\'':
squoting = 1 - squoting;
/* Fall through. */
default:
comm = w_addchar (comm, &comm_length, &comm_maxlen, words[*offset]);
if (comm == NULL)
return WRDE_NOSPACE;
}
}
/* Premature end */
free (comm);
return WRDE_SYNTAX;
}
static int
parse_dquote (char **word, size_t *word_length, size_t *max_length,
const char *words, size_t *offset, int flags,
wordexp_t *pwordexp, const char * ifs, const char * ifs_white)
{
/* We are poised just after a double-quote */
int error;
for (; words[*offset]; ++(*offset))
{
switch (words[*offset])
{
case '"':
return 0;
case '$':
error = parse_dollars (word, word_length, max_length, words, offset,
flags, pwordexp, ifs, ifs_white, 1);
/* The ``1'' here is to tell parse_dollars not to
* split the fields. It may need to, however ("$@").
*/
if (error)
return error;
break;
case '`':
++(*offset);
error = parse_backtick (word, word_length, max_length, words,
offset, flags, NULL, NULL, NULL);
/* The first NULL here is to tell parse_backtick not to
* split the fields.
*/
if (error)
return error;
break;
case '\\':
error = parse_qtd_backslash (word, word_length, max_length, words,
offset);
if (error)
return error;
break;
default:
*word = w_addchar (*word, word_length, max_length, words[*offset]);
if (*word == NULL)
return WRDE_NOSPACE;
}
}
/* Unterminated string */
return WRDE_SYNTAX;
}
/*
* wordfree() is to be called after pwordexp is finished with.
*/
void
wordfree (wordexp_t *pwordexp)
{
/* wordexp can set pwordexp to NULL */
if (pwordexp && pwordexp->we_wordv)
{
char **wordv = pwordexp->we_wordv;
for (wordv += pwordexp->we_offs; *wordv; ++wordv)
free (*wordv);
free (pwordexp->we_wordv);
pwordexp->we_wordv = NULL;
}
}
libc_hidden_def (wordfree)
/*
* wordexp()
*/
int
wordexp (const char *words, wordexp_t *pwordexp, int flags)
{
size_t words_offset;
size_t word_length;
size_t max_length;
char *word = w_newword (&word_length, &max_length);
int error;
char *ifs;
char ifs_white[4];
wordexp_t old_word = *pwordexp;
if (flags & WRDE_REUSE)
{
/* Minimal implementation of WRDE_REUSE for now */
wordfree (pwordexp);
old_word.we_wordv = NULL;
}
if ((flags & WRDE_APPEND) == 0)
{
pwordexp->we_wordc = 0;
if (flags & WRDE_DOOFFS)
{
pwordexp->we_wordv = calloc (1 + pwordexp->we_offs, sizeof (char *));
if (pwordexp->we_wordv == NULL)
{
error = WRDE_NOSPACE;
goto do_error;
}
}
else
{
pwordexp->we_wordv = calloc (1, sizeof (char *));
if (pwordexp->we_wordv == NULL)
{
error = WRDE_NOSPACE;
goto do_error;
}
pwordexp->we_offs = 0;
}
}
/* Find out what the field separators are.
* There are two types: whitespace and non-whitespace.
*/
ifs = getenv ("IFS");
if (ifs == NULL)
/* IFS unset - use <space><tab><newline>. */
ifs = strcpy (ifs_white, " \t\n");
else
{
char *ifsch = ifs;
char *whch = ifs_white;
while (*ifsch != '\0')
{
if (*ifsch == ' ' || *ifsch == '\t' || *ifsch == '\n')
{
/* Whitespace IFS. See first whether it is already in our
collection. */
char *runp = ifs_white;
while (runp < whch && *runp != *ifsch)
++runp;
if (runp == whch)
*whch++ = *ifsch;
}
++ifsch;
}
*whch = '\0';
}
for (words_offset = 0 ; words[words_offset] ; ++words_offset)
switch (words[words_offset])
{
case '\\':
error = parse_backslash (&word, &word_length, &max_length, words,
&words_offset);
if (error)
goto do_error;
break;
case '$':
error = parse_dollars (&word, &word_length, &max_length, words,
&words_offset, flags, pwordexp, ifs, ifs_white,
0);
if (error)
goto do_error;
break;
case '`':
++words_offset;
error = parse_backtick (&word, &word_length, &max_length, words,
&words_offset, flags, pwordexp, ifs,
ifs_white);
if (error)
goto do_error;
break;
case '"':
++words_offset;
error = parse_dquote (&word, &word_length, &max_length, words,
&words_offset, flags, pwordexp, ifs, ifs_white);
if (error)
goto do_error;
if (!word_length)
{
error = w_addword (pwordexp, NULL);
if (error)
return error;
}
break;
case '\'':
++words_offset;
error = parse_squote (&word, &word_length, &max_length, words,
&words_offset);
if (error)
goto do_error;
if (!word_length)
{
error = w_addword (pwordexp, NULL);
if (error)
return error;
}
break;
case '~':
error = parse_tilde (&word, &word_length, &max_length, words,
&words_offset, pwordexp->we_wordc);
if (error)
goto do_error;
break;
case '*':
case '[':
case '?':
error = parse_glob (&word, &word_length, &max_length, words,
&words_offset, flags, pwordexp, ifs, ifs_white);
if (error)
goto do_error;
break;
default:
/* Is it a word separator? */
if (strchr (" \t", words[words_offset]) == NULL)
{
char ch = words[words_offset];
/* Not a word separator -- but is it a valid word char? */
if (strchr ("\n|&;<>(){}", ch))
{
/* Fail */
error = WRDE_BADCHAR;
goto do_error;
}
/* "Ordinary" character -- add it to word */
word = w_addchar (word, &word_length, &max_length,
ch);
if (word == NULL)
{
error = WRDE_NOSPACE;
goto do_error;
}
break;
}
/* If a word has been delimited, add it to the list. */
if (word != NULL)
{
error = w_addword (pwordexp, word);
if (error)
goto do_error;
}
word = w_newword (&word_length, &max_length);
}
/* End of string */
/* There was a word separator at the end */
if (word == NULL) /* i.e. w_newword */
return 0;
/* There was no field separator at the end */
return w_addword (pwordexp, word);
do_error:
/* Error:
* free memory used (unless error is WRDE_NOSPACE), and
* set pwordexp members back to what they were.
*/
free (word);
if (error == WRDE_NOSPACE)
return WRDE_NOSPACE;
if ((flags & WRDE_APPEND) == 0)
wordfree (pwordexp);
*pwordexp = old_word;
return error;
}