From 075945f611290f2b9db9a4ed6cf5433f2fd85785 Mon Sep 17 00:00:00 2001 From: "John (J5) Palmieri" Date: Thu, 14 Jul 2005 20:44:15 +0000 Subject: Checking in Rodrigo's patch along with my fixes to the patch 2005-07-14 John (J5) Palmieri * bus/activation.c: clean up all tabs to be 8 spaces (bus_activation_activate_service): make sure we clean up if activation fails * bus/dispatch.c: clean up all tabs to be 8 spaces (check_shell_fail_service_auto_start): New function tests to make sure we get fail properly when trying to auto start a service with a faulty command line (check_shell_service_success_auto_start): New function tests to make sure auto started services get the arguments on the command line * test/test-shell-service.c: Added service for testing auto-starting with command line arguments * test/data/valid-service-files/debug-shell-echo-fail.service.in, test/data/valid-service-files/debug-shell-echo-success.service.in: Added service files for testing auto-starting with command line arguments * */.cvsignore: added a bunch of generated files to various .cvsignore files 2005-07-14 Rodrigo Moya * dbus/dbus-shell.[ch]: copy/pasted code from GLib. * dbus/Makefile.am: added new files to build. * bus/activation.c (bus_activation_activate_service): support activation commands with parameters. * test/shell-test.c: added test program for the shell parsing code. --- dbus/dbus-shell.c | 706 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 706 insertions(+) create mode 100644 dbus/dbus-shell.c (limited to 'dbus/dbus-shell.c') diff --git a/dbus/dbus-shell.c b/dbus/dbus-shell.c new file mode 100644 index 00000000..02d8cc81 --- /dev/null +++ b/dbus/dbus-shell.c @@ -0,0 +1,706 @@ +/* -*- mode: C; c-file-style: "gnu" -*- */ +/* 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 +#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; +} + +/** + * Quotes a string so that the shell (/bin/sh) will interpret the + * quoted string to mean @unquoted_string. If you pass a filename to + * the shell, for example, you should first quote it with this + * function. The return value must be freed with dbus_free(). The + * quoting style used is undefined (single or double quotes may be + * used). + * + * @unquoted_string: a literal string + **/ +char* +_dbus_shell_quote (const char *unquoted_string) +{ + /* We always use single quotes, because the algorithm is cheesier. + * We could use double if we felt like it, that might be more + * human-readable. + */ + + const char *p; + char *ret; + DBusString dest; + + _dbus_string_init (&dest); + + p = unquoted_string; + + /* could speed this up a lot by appending chunks of text at a + * time. + */ + while (*p) + { + /* Replace literal ' with a close ', a \', and a open ' */ + if (*p == '\'') + { + if (!_dbus_string_append (&dest, "'\\''")) + { + _dbus_string_free (&dest); + return NULL; + } + } + else + { + if (!_dbus_string_append_byte (&dest, *p)) + { + _dbus_string_free (&dest); + return NULL; + } + } + + ++p; + } + + /* close the quote */ + if (_dbus_string_append_byte (&dest, '\'')) + { + ret = _dbus_strdup (_dbus_string_get_data (&dest)); + _dbus_string_free (&dest); + + return ret; + } + + _dbus_string_free (&dest); + + return NULL; +} + +/** + * 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; + +} -- cgit