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-rw-r--r--posix/wordexp.c2457
1 files changed, 2457 insertions, 0 deletions
diff --git a/posix/wordexp.c b/posix/wordexp.c
new file mode 100644
index 0000000000..2eb58089c4
--- /dev/null
+++ b/posix/wordexp.c
@@ -0,0 +1,2457 @@
+/* POSIX.2 wordexp implementation.
+ Copyright (C) 1997-2002, 2003, 2005 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <alloca.h>
+#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 <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>
+#ifdef USE_IN_LIBIO
+# include <wchar.h>
+#endif
+#include <wordexp.h>
+
+#include <bits/libc-lock.h>
+#include <stdio-common/_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)
+ internal_function;
+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)
+ internal_function;
+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)
+ internal_function;
+static int eval_expr (char *expr, long int *result) internal_function;
+
+/* 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 *
+internal_function
+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 *
+internal_function
+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
+internal_function
+w_addword (wordexp_t *pwordexp, char *word)
+{
+ /* Add a word to the wordlist */
+ size_t num_p;
+ char **new_wordv;
+
+ /* Internally, NULL acts like "". Convert NULLs to "" before
+ * the caller sees them.
+ */
+ if (word == NULL)
+ {
+ word = __strdup ("");
+ if (word == NULL)
+ goto no_space;
+ }
+
+ 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;
+ }
+
+no_space:
+ return WRDE_NOSPACE;
+}
+
+/* The parse_*() functions should leave *offset being the offset in 'words'
+ * to the last character processed.
+ */
+
+static int
+internal_function
+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
+internal_function
+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
+internal_function
+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 */
+ uid_t uid;
+ struct passwd pwd, *tpwd;
+ int buflen = 1000;
+ char* home;
+ char* buffer;
+ int result;
+
+ /* 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
+ {
+ uid = __getuid ();
+ buffer = __alloca (buflen);
+
+ while ((result = __getpwuid_r (uid, &pwd, buffer, buflen, &tpwd)) != 0
+ && errno == ERANGE)
+ buffer = extend_alloca (buffer, buflen, buflen + 1000);
+
+ if (result == 0 && tpwd != NULL && pwd.pw_dir != NULL)
+ {
+ *word = w_addstr (*word, word_length, max_length, pwd.pw_dir);
+ if (*word == NULL)
+ return WRDE_NOSPACE;
+ }
+ else
+ {
+ *word = w_addchar (*word, word_length, max_length, '~');
+ if (*word == NULL)
+ return WRDE_NOSPACE;
+ }
+ }
+ }
+ 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 buflen = 1000;
+ char* buffer = __alloca (buflen);
+ int result;
+
+ while ((result = __getpwnam_r (user, &pwd, buffer, buflen, &tpwd)) != 0
+ && errno == ERANGE)
+ buffer = extend_alloca (buffer, buflen, buflen + 1000);
+
+ 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);
+ }
+
+ *offset = i - 1;
+ }
+ return *word ? 0 : WRDE_NOSPACE;
+}
+
+
+static int
+internal_function
+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
+internal_function
+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 ((ifs && strchr (ifs, words[*offset])) ||
+ (!ifs && strchr (" \t\n", words[*offset])))
+ /* 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
+internal_function
+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
+internal_function
+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
+internal_function
+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;
+
+ *result /= arg;
+ }
+ else break;
+ }
+
+ return 0;
+}
+
+static int
+internal_function
+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
+internal_function
+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;
+ 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
+internal_function __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. */
+ __dup2 (fildes[1], STDOUT_FILENO);
+ __close (fildes[1]);
+
+ /* Redirect stderr to /dev/null if we have to. */
+ if (showerr == 0)
+ {
+ struct stat64 st;
+ int fd;
+ __close (2);
+ fd = __open (_PATH_DEVNULL, O_WRONLY);
+ if (fd >= 0 && fd != 2)
+ {
+ __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 != 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
+internal_function
+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;
+
+ /* Don't fork() unless necessary */
+ if (!comm || !*comm)
+ return 0;
+
+ if (__pipe (fildes))
+ /* Bad */
+ return WRDE_NOSPACE;
+
+ again:
+ if ((pid = __fork ()) < 0)
+ {
+ /* Bad */
+ if (fildes[0] != -1)
+ __close (fildes[0]);
+ if (fildes[1] != -1)
+ __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 (TEMP_FAILURE_RETRY (__waitpid (pid, &status, 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 (TEMP_FAILURE_RETRY (__waitpid (pid, &status, 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
+internal_function
+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 */
+ if (comm)
+ free (comm);
+
+ return WRDE_SYNTAX;
+}
+
+static int
+internal_function
+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 "$" */
+ enum action
+ {
+ ACT_NONE,
+ ACT_RP_SHORT_LEFT = '#',
+ ACT_RP_LONG_LEFT = 'L',
+ ACT_RP_SHORT_RIGHT = '%',
+ ACT_RP_LONG_RIGHT = 'R',
+ ACT_NULL_ERROR = '?',
+ ACT_NULL_SUBST = '-',
+ ACT_NONNULL_SUBST = '+',
+ ACT_NULL_ASSIGN = '='
+ };
+ size_t env_length;
+ size_t env_maxlen;
+ size_t pat_length;
+ size_t pat_maxlen;
+ size_t start = *offset;
+ char *env;
+ char *pattern;
+ char *value = NULL;
+ enum action action = ACT_NONE;
+ int depth = 0;
+ int colon_seen = 0;
+ int seen_hash = 0;
+ int free_value = 0;
+ int pattern_is_quoted = 0; /* 1 for singly-quoted, 2 for doubly-quoted */
+ int error;
+ int special = 0;
+ char buffer[21];
+ int brace = words[*offset] == '{';
+
+ env = w_newword (&env_length, &env_maxlen);
+ pattern = w_newword (&pat_length, &pat_maxlen);
+
+ if (brace)
+ ++*offset;
+
+ /* First collect the parameter name. */
+
+ if (words[*offset] == '#')
+ {
+ seen_hash = 1;
+ if (!brace)
+ goto envsubst;
+ ++*offset;
+ }
+
+ if (isalpha (words[*offset]) || words[*offset] == '_')
+ {
+ /* Normal parameter name. */
+ do
+ {
+ env = w_addchar (env, &env_length, &env_maxlen,
+ words[*offset]);
+ if (env == NULL)
+ goto no_space;
+ }
+ while (isalnum (words[++*offset]) || words[*offset] == '_');
+ }
+ else if (isdigit (words[*offset]))
+ {
+ /* Numeric parameter name. */
+ special = 1;
+ do
+ {
+ env = w_addchar (env, &env_length, &env_maxlen,
+ words[*offset]);
+ if (env == NULL)
+ goto no_space;
+ if (!brace)
+ goto envsubst;
+ }
+ while (isdigit(words[++*offset]));
+ }
+ else if (strchr ("*@$", words[*offset]) != NULL)
+ {
+ /* 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 (strchr ("-=?+", words[1 + *offset]) == NULL)
+ 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 `${#@}'? */
+ else if ((*env == '*' || *env == '@') && seen_hash)
+ {
+ buffer[20] = '\0';
+ value = _itoa_word (__libc_argc > 0 ? __libc_argc - 1 : 0,
+ &buffer[20], 10, 0);
+ *word = w_addstr (*word, word_length, max_length, value);
+ free (env);
+ if (pattern)
+ free (pattern);
+ return *word ? 0 : WRDE_NOSPACE;
+ }
+ /* Is it `$*' 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);
+
+ if (expanded)
+ 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);
+
+ if (expanded)
+ 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;
+ }
+
+ if (pattern)
+ 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 && 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 && 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 && 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,
+ &param_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:
+ if (env)
+ free (env);
+
+ if (pattern)
+ free (pattern);
+
+ return error;
+}
+
+static int
+internal_function
+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);
+ }
+ }
+
+ if (flags & WRDE_NOCMD)
+ return WRDE_CMDSUB;
+
+ (*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
+internal_function
+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;
+ }
+
+ ++(*offset);
+ error = parse_backslash (&comm, &comm_length, &comm_maxlen, words,
+ offset);
+
+ if (error)
+ {
+ free (comm);
+ return error;
+ }
+
+ break;
+
+ case '\'':
+ squoting = 1 - squoting;
+ 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
+internal_function
+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 '`':
+ if (flags & WRDE_NOCMD)
+ return WRDE_CMDSUB;
+
+ ++(*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)
+ /* IFS unset - use <space><tab><newline>. */
+ ifs = strcpy (ifs_white, " \t\n");
+ else
+ {
+ char *ifsch = ifs;
+ char *whch = ifs_white;
+
+ /* Start off with no whitespace IFS characters */
+ ifs_white[0] = '\0';
+
+ 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 != '\0' && *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 '`':
+ if (flags & WRDE_NOCMD)
+ {
+ error = WRDE_CMDSUB;
+ goto do_error;
+ }
+
+ ++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.
+ */
+
+ if (word != NULL)
+ free (word);
+
+ if (error == WRDE_NOSPACE)
+ return WRDE_NOSPACE;
+
+ if ((flags & WRDE_APPEND) == 0)
+ wordfree (pwordexp);
+
+ *pwordexp = old_word;
+ return error;
+}
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