--- /dev/null
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+/* dbus-shell.c Shell command line utility functions.
+ *
+ * Copyright (C) 2002, 2003 Red Hat, Inc.
+ * Copyright (C) 2003 CodeFactory AB
+ *
+ * Licensed under the Academic Free License version 2.1
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <string.h>
+#include "dbus-internals.h"
+#include "dbus-list.h"
+#include "dbus-memory.h"
+#include "dbus-protocol.h"
+#include "dbus-shell.h"
+#include "dbus-string.h"
+
+/* Single quotes preserve the literal string exactly. escape
+ * sequences are not allowed; not even \' - if you want a '
+ * in the quoted text, you have to do something like 'foo'\''bar'
+ *
+ * Double quotes allow $ ` " \ and newline to be escaped with backslash.
+ * Otherwise double quotes preserve things literally.
+ */
+
+static dbus_bool_t
+unquote_string_inplace (char* str, char** end)
+{
+ char* dest;
+ char* s;
+ char quote_char;
+
+ dest = s = str;
+
+ quote_char = *s;
+
+ if (!(*s == '"' || *s == '\''))
+ {
+ *end = str;
+ return FALSE;
+ }
+
+ /* Skip the initial quote mark */
+ ++s;
+
+ if (quote_char == '"')
+ {
+ while (*s)
+ {
+ _dbus_assert(s > dest); /* loop invariant */
+
+ switch (*s)
+ {
+ case '"':
+ /* End of the string, return now */
+ *dest = '\0';
+ ++s;
+ *end = s;
+ return TRUE;
+
+ case '\\':
+ /* Possible escaped quote or \ */
+ ++s;
+ switch (*s)
+ {
+ case '"':
+ case '\\':
+ case '`':
+ case '$':
+ case '\n':
+ *dest = *s;
+ ++s;
+ ++dest;
+ break;
+
+ default:
+ /* not an escaped char */
+ *dest = '\\';
+ ++dest;
+ /* ++s already done. */
+ break;
+ }
+ break;
+
+ default:
+ *dest = *s;
+ ++dest;
+ ++s;
+ break;
+ }
+
+ _dbus_assert(s > dest); /* loop invariant */
+ }
+ }
+ else
+ {
+ while (*s)
+ {
+ _dbus_assert(s > dest); /* loop invariant */
+
+ if (*s == '\'')
+ {
+ /* End of the string, return now */
+ *dest = '\0';
+ ++s;
+ *end = s;
+ return TRUE;
+ }
+ else
+ {
+ *dest = *s;
+ ++dest;
+ ++s;
+ }
+
+ _dbus_assert(s > dest); /* loop invariant */
+ }
+ }
+
+ /* If we reach here this means the close quote was never encountered */
+
+ *dest = '\0';
+
+ *end = s;
+ return FALSE;
+}
+
+/**
+ * Unquotes a string as the shell (/bin/sh) would. Only handles
+ * quotes; if a string contains file globs, arithmetic operators,
+ * variables, backticks, redirections, or other special-to-the-shell
+ * features, the result will be different from the result a real shell
+ * would produce (the variables, backticks, etc. will be passed
+ * through literally instead of being expanded). This function is
+ * guaranteed to succeed if applied to the result of
+ * _dbus_shell_quote(). If it fails, it returns %NULL.
+ * The @quoted_string need not actually contain quoted or
+ * escaped text; _dbus_shell_unquote() simply goes through the string and
+ * unquotes/unescapes anything that the shell would. Both single and
+ * double quotes are handled, as are escapes including escaped
+ * newlines. The return value must be freed with dbus_free().
+ *
+ * Shell quoting rules are a bit strange. Single quotes preserve the
+ * literal string exactly. escape sequences are not allowed; not even
+ * \' - if you want a ' in the quoted text, you have to do something
+ * like 'foo'\''bar'. Double quotes allow $, `, ", \, and newline to
+ * be escaped with backslash. Otherwise double quotes preserve things
+ * literally.
+ *
+ * @quoted_string: shell-quoted string
+ **/
+char*
+_dbus_shell_unquote (const char *quoted_string)
+{
+ char *unquoted;
+ char *end;
+ char *start;
+ char *ret;
+ DBusString retval;
+
+ unquoted = _dbus_strdup (quoted_string);
+ if (unquoted == NULL)
+ return NULL;
+
+ start = unquoted;
+ end = unquoted;
+ if (!_dbus_string_init (&retval))
+ {
+ dbus_free (unquoted);
+ return NULL;
+ }
+
+ /* The loop allows cases such as
+ * "foo"blah blah'bar'woo foo"baz"la la la\'\''foo'
+ */
+ while (*start)
+ {
+ /* Append all non-quoted chars, honoring backslash escape
+ */
+
+ while (*start && !(*start == '"' || *start == '\''))
+ {
+ if (*start == '\\')
+ {
+ /* all characters can get escaped by backslash,
+ * except newline, which is removed if it follows
+ * a backslash outside of quotes
+ */
+
+ ++start;
+ if (*start)
+ {
+ if (*start != '\n')
+ {
+ if (!_dbus_string_append_byte (&retval, *start))
+ goto error;
+ }
+ ++start;
+ }
+ }
+ else
+ {
+ if (!_dbus_string_append_byte (&retval, *start))
+ goto error;
+ ++start;
+ }
+ }
+
+ if (*start)
+ {
+ if (!unquote_string_inplace (start, &end))
+ goto error;
+ else
+ {
+ if (!_dbus_string_append (&retval, start))
+ goto error;
+ start = end;
+ }
+ }
+ }
+
+ ret = _dbus_strdup (_dbus_string_get_data (&retval));
+ if (!ret)
+ goto error;
+
+ dbus_free (unquoted);
+ _dbus_string_free (&retval);
+
+ return ret;
+
+ error:
+ dbus_free (unquoted);
+ _dbus_string_free (&retval);
+ return NULL;
+}
+
+/* _dbus_shell_parse_argv() does a semi-arbitrary weird subset of the way
+ * the shell parses a command line. We don't do variable expansion,
+ * don't understand that operators are tokens, don't do tilde expansion,
+ * don't do command substitution, no arithmetic expansion, IFS gets ignored,
+ * don't do filename globs, don't remove redirection stuff, etc.
+ *
+ * READ THE UNIX98 SPEC on "Shell Command Language" before changing
+ * the behavior of this code.
+ *
+ * Steps to parsing the argv string:
+ *
+ * - tokenize the string (but since we ignore operators,
+ * our tokenization may diverge from what the shell would do)
+ * note that tokenization ignores the internals of a quoted
+ * word and it always splits on spaces, not on IFS even
+ * if we used IFS. We also ignore "end of input indicator"
+ * (I guess this is control-D?)
+ *
+ * Tokenization steps, from UNIX98 with operator stuff removed,
+ * are:
+ *
+ * 1) "If the current character is backslash, single-quote or
+ * double-quote (\, ' or ") and it is not quoted, it will affect
+ * quoting for subsequent characters up to the end of the quoted
+ * text. The rules for quoting are as described in Quoting
+ * . During token recognition no substitutions will be actually
+ * performed, and the result token will contain exactly the
+ * characters that appear in the input (except for newline
+ * character joining), unmodified, including any embedded or
+ * enclosing quotes or substitution operators, between the quote
+ * mark and the end of the quoted text. The token will not be
+ * delimited by the end of the quoted field."
+ *
+ * 2) "If the current character is an unquoted newline character,
+ * the current token will be delimited."
+ *
+ * 3) "If the current character is an unquoted blank character, any
+ * token containing the previous character is delimited and the
+ * current character will be discarded."
+ *
+ * 4) "If the previous character was part of a word, the current
+ * character will be appended to that word."
+ *
+ * 5) "If the current character is a "#", it and all subsequent
+ * characters up to, but excluding, the next newline character
+ * will be discarded as a comment. The newline character that
+ * ends the line is not considered part of the comment. The
+ * "#" starts a comment only when it is at the beginning of a
+ * token. Since the search for the end-of-comment does not
+ * consider an escaped newline character specially, a comment
+ * cannot be continued to the next line."
+ *
+ * 6) "The current character will be used as the start of a new word."
+ *
+ *
+ * - for each token (word), perform portions of word expansion, namely
+ * field splitting (using default whitespace IFS) and quote
+ * removal. Field splitting may increase the number of words.
+ * Quote removal does not increase the number of words.
+ *
+ * "If the complete expansion appropriate for a word results in an
+ * empty field, that empty field will be deleted from the list of
+ * fields that form the completely expanded command, unless the
+ * original word contained single-quote or double-quote characters."
+ * - UNIX98 spec
+ *
+ *
+ */
+
+static dbus_bool_t
+delimit_token (DBusString *token,
+ DBusList **retval,
+ DBusError *error)
+{
+ char *str;
+
+ str = _dbus_strdup (_dbus_string_get_data (token));
+ if (!str)
+ {
+ _DBUS_SET_OOM (error);
+ return FALSE;
+ }
+
+ if (!_dbus_list_append (retval, str))
+ {
+ dbus_free (str);
+ _DBUS_SET_OOM (error);
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+static DBusList*
+tokenize_command_line (const char *command_line, DBusError *error)
+{
+ char current_quote;
+ const char *p;
+ DBusString current_token;
+ DBusList *retval = NULL;
+ dbus_bool_t quoted;;
+
+ current_quote = '\0';
+ quoted = FALSE;
+ p = command_line;
+
+ if (!_dbus_string_init (¤t_token))
+ {
+ _DBUS_SET_OOM (error);
+ return NULL;
+ }
+
+ while (*p)
+ {
+ if (current_quote == '\\')
+ {
+ if (*p == '\n')
+ {
+ /* we append nothing; backslash-newline become nothing */
+ }
+ else
+ {
+ if (!_dbus_string_append_byte (¤t_token, '\\') ||
+ !_dbus_string_append_byte (¤t_token, *p))
+ {
+ _DBUS_SET_OOM (error);
+ goto error;
+ }
+ }
+
+ current_quote = '\0';
+ }
+ else if (current_quote == '#')
+ {
+ /* Discard up to and including next newline */
+ while (*p && *p != '\n')
+ ++p;
+
+ current_quote = '\0';
+
+ if (*p == '\0')
+ break;
+ }
+ else if (current_quote)
+ {
+ if (*p == current_quote &&
+ /* check that it isn't an escaped double quote */
+ !(current_quote == '"' && quoted))
+ {
+ /* close the quote */
+ current_quote = '\0';
+ }
+
+ /* Everything inside quotes, and the close quote,
+ * gets appended literally.
+ */
+
+ if (!_dbus_string_append_byte (¤t_token, *p))
+ {
+ _DBUS_SET_OOM (error);
+ goto error;
+ }
+ }
+ else
+ {
+ switch (*p)
+ {
+ case '\n':
+ if (!delimit_token (¤t_token, &retval, error))
+ goto error;
+
+ _dbus_string_free (¤t_token);
+
+ if (!_dbus_string_init (¤t_token))
+ {
+ _DBUS_SET_OOM (error);
+ goto init_error;
+ }
+
+ break;
+
+ case ' ':
+ case '\t':
+ /* If the current token contains the previous char, delimit
+ * the current token. A nonzero length
+ * token should always contain the previous char.
+ */
+ if (_dbus_string_get_length (¤t_token) > 0)
+ {
+ if (!delimit_token (¤t_token, &retval, error))
+ goto error;
+
+ _dbus_string_free (¤t_token);
+
+ if (!_dbus_string_init (¤t_token))
+ {
+ _DBUS_SET_OOM (error);
+ goto init_error;
+ }
+
+ }
+
+ /* discard all unquoted blanks (don't add them to a token) */
+ break;
+
+
+ /* single/double quotes are appended to the token,
+ * escapes are maybe appended next time through the loop,
+ * comment chars are never appended.
+ */
+
+ case '\'':
+ case '"':
+ if (!_dbus_string_append_byte (¤t_token, *p))
+ {
+ _DBUS_SET_OOM (error);
+ goto error;
+ }
+
+ /* FALL THRU */
+
+ case '#':
+ case '\\':
+ current_quote = *p;
+ break;
+
+ default:
+ /* Combines rules 4) and 6) - if we have a token, append to it,
+ * otherwise create a new token.
+ */
+ if (!_dbus_string_append_byte (¤t_token, *p))
+ {
+ _DBUS_SET_OOM (error);
+ goto error;
+ }
+ break;
+ }
+ }
+
+ /* We need to count consecutive backslashes mod 2,
+ * to detect escaped doublequotes.
+ */
+ if (*p != '\\')
+ quoted = FALSE;
+ else
+ quoted = !quoted;
+
+ ++p;
+ }
+
+ if (!delimit_token (¤t_token, &retval, error))
+ goto error;
+
+ if (current_quote)
+ {
+ dbus_set_error_const (error, DBUS_ERROR_INVALID_ARGS, "Unclosed quotes in command line");
+ goto error;
+ }
+
+ if (retval == NULL)
+ {
+ dbus_set_error_const (error, DBUS_ERROR_INVALID_ARGS, "No tokens found in command line");
+ goto error;
+ }
+
+ _dbus_string_free (¤t_token);
+
+ return retval;
+
+ error:
+ _dbus_string_free (¤t_token);
+
+ init_error:
+ if (retval)
+ {
+ _dbus_list_foreach (&retval, (DBusForeachFunction) dbus_free, NULL);
+ _dbus_list_clear (&retval);
+ }
+
+ return NULL;
+}
+
+/**
+ * _dbus_shell_parse_argv:
+ *
+ * Parses a command line into an argument vector, in much the same way
+ * the shell would, but without many of the expansions the shell would
+ * perform (variable expansion, globs, operators, filename expansion,
+ * etc. are not supported). The results are defined to be the same as
+ * those you would get from a UNIX98 /bin/sh, as long as the input
+ * contains none of the unsupported shell expansions. If the input
+ * does contain such expansions, they are passed through
+ * literally. Free the returned vector with dbus_free_string_array().
+ *
+ * @command_line: command line to parse
+ * @argcp: return location for number of args
+ * @argvp: return location for array of args
+ * @error: error information
+ **/
+dbus_bool_t
+_dbus_shell_parse_argv (const char *command_line,
+ int *argcp,
+ char ***argvp,
+ DBusError *error)
+{
+ /* Code based on poptParseArgvString() from libpopt */
+ int argc = 0;
+ char **argv = NULL;
+ DBusList *tokens = NULL;
+ int i;
+ DBusList *tmp_list;
+
+ if (!command_line)
+ {
+ _dbus_verbose ("Command line is NULL\n");
+ return FALSE;
+ }
+
+ tokens = tokenize_command_line (command_line, error);
+ if (tokens == NULL)
+ {
+ _dbus_verbose ("No tokens for command line '%s'\n", command_line);
+ return FALSE;
+ }
+
+ /* Because we can't have introduced any new blank space into the
+ * tokens (we didn't do any new expansions), we don't need to
+ * perform field splitting. If we were going to honor IFS or do any
+ * expansions, we would have to do field splitting on each word
+ * here. Also, if we were going to do any expansion we would need to
+ * remove any zero-length words that didn't contain quotes
+ * originally; but since there's no expansion we know all words have
+ * nonzero length, unless they contain quotes.
+ *
+ * So, we simply remove quotes, and don't do any field splitting or
+ * empty word removal, since we know there was no way to introduce
+ * such things.
+ */
+
+ argc = _dbus_list_get_length (&tokens);
+ argv = dbus_new (char *, argc + 1);
+ if (!argv)
+ {
+ _DBUS_SET_OOM (error);
+ goto error;
+ }
+
+ i = 0;
+ tmp_list = tokens;
+ while (tmp_list)
+ {
+ argv[i] = _dbus_shell_unquote (tmp_list->data);
+
+ if (!argv[i])
+ {
+ int j;
+ for (j = 0; j < i; j++)
+ dbus_free(argv[j]);
+
+ dbus_free (argv);
+ _DBUS_SET_OOM (error);
+ goto error;
+ }
+
+ tmp_list = _dbus_list_get_next_link (&tokens, tmp_list);
+ ++i;
+ }
+ argv[argc] = NULL;
+
+ _dbus_list_foreach (&tokens, (DBusForeachFunction) dbus_free, NULL);
+ _dbus_list_clear (&tokens);
+
+ if (argcp)
+ *argcp = argc;
+
+ if (argvp)
+ *argvp = argv;
+ else
+ dbus_free_string_array (argv);
+
+ return TRUE;
+
+ error:
+ _dbus_list_foreach (&tokens, (DBusForeachFunction) dbus_free, NULL);
+ _dbus_list_clear (&tokens);
+
+ return FALSE;
+
+}
projects / monky / blobdiff