From 22cee80bc2f631703bf417a54ef4e0f0837e921a Mon Sep 17 00:00:00 2001 From: Matthew Booth Date: Fri, 11 Sep 2009 09:27:57 +0100 Subject: [PATCH] guestfish: Enable grouping in string lists This change adds the ability to group entries in a string list with single quotes. So the string: "'foo bar'" becomes 1 token rather than 2. Consequently single quotes must now be escaped: "\'" resolves to a literal single quote. Incidentally, this change also alters another, probably unintentional behaviour of the previous implementation, in that tokens are separated by any amount of whitespace rather than a single whitespace character. I.e.: "a b" resolves to: 'a' 'b' rather than: 'a' '' 'b' That last syntax can be used if an empty argument is still desired. Whitespace is now also defined to include tabs. parse_string_list can also now fail if it contains an unmatched open quote. --- fish/fish.c | 150 ++++++++++++++++++++++++++++++++++++----- guestfish.pod | 6 +- regressions/Makefile.am | 3 +- regressions/test-stringlist.sh | 60 +++++++++++++++++ src/generator.ml | 3 +- 5 files changed, 202 insertions(+), 20 deletions(-) create mode 100755 regressions/test-stringlist.sh diff --git a/fish/fish.c b/fish/fish.c index a4069d6..9316eda 100644 --- a/fish/fish.c +++ b/fish/fish.c @@ -1082,30 +1082,146 @@ is_true (const char *str) strcasecmp (str, "no") != 0; } -/* XXX We could improve list parsing. */ +/* Free strings from a non-NULL terminated char** */ +static void +free_n_strings (char **str, size_t len) +{ + for (size_t i = 0; i < len; i++) { + free (str[i]); + } + free (str); +} + char ** parse_string_list (const char *str) { - char **argv; - const char *p, *pend; - int argc, i; + char **argv = NULL; + size_t argv_len = 0; + + /* Current position pointer */ + const char *p = str; + + /* Token might be simple: + * Token + * or be quoted: + * 'This is a single token' + * or contain embedded single-quoted sections: + * This' is a sing'l'e to'ken + * + * The latter may seem over-complicated, but it's what a normal shell does. + * Not doing it risks surprising somebody. + * + * This outer loop is over complete tokens. + */ + while (*p) { + char *tok = NULL; + size_t tok_len = 0; - argc = 1; - for (i = 0; str[i]; ++i) - if (str[i] == ' ') argc++; + /* Skip leading whitespace */ + p += strspn (p, " \t"); - argv = malloc (sizeof (char *) * (argc+1)); - if (argv == NULL) { perror ("malloc"); exit (1); } + char in_quote = 0; - p = str; - i = 0; - while (*p) { - pend = strchrnul (p, ' '); - argv[i] = strndup (p, pend-p); - i++; - p = *pend == ' ' ? pend+1 : pend; + /* This loop is over token 'fragments'. A token can be in multiple bits if + * it contains single quotes. We also treat both sides of an escaped quote + * as separate fragments because we can't just copy it: we have to remove + * the \. + */ + while (*p && (!isblank (*p) || in_quote)) { + const char *end = p; + + /* Check if the fragment starts with a quote */ + if ('\'' == *p) { + /* Toggle in_quote */ + in_quote = !in_quote; + + /* Skip the quote */ + p++; end++; + } + + /* If we're in a quote, look for an end quote */ + if (in_quote) { + end += strcspn (end, "'"); + } + + /* Otherwise, look for whitespace or a quote */ + else { + end += strcspn (end, " \t'"); + } + + /* Grow the token to accommodate the fragment */ + size_t tok_end = tok_len; + tok_len += end - p; + char *tok_new = realloc (tok, tok_len + 1); + if (NULL == tok_new) { + perror ("realloc"); + free_n_strings (argv, argv_len); + free (tok); + exit (1); + } + tok = tok_new; + + /* Check if we stopped on an escaped quote */ + if ('\'' == *end && end != p && *(end-1) == '\\') { + /* Add everything before \' to the token */ + memcpy (&tok[tok_end], p, end - p - 1); + + /* Add the quote */ + tok[tok_len-1] = '\''; + + /* Already processed the quote */ + p = end + 1; + } + + else { + /* Add the whole fragment */ + memcpy (&tok[tok_end], p, end - p); + + p = end; + } + } + + /* We've reached the end of a token. We shouldn't still be in quotes. */ + if (in_quote) { + fprintf (stderr, _("Runaway quote in string \"%s\"\n"), str); + + free_n_strings (argv, argv_len); + + return NULL; + } + + /* Add this token if there is one. There might not be if there was + * whitespace at the end of the input string */ + if (tok) { + /* Add the NULL terminator */ + tok[tok_len] = '\0'; + + /* Add the argument to the argument list */ + argv_len++; + char **argv_new = realloc (argv, sizeof (*argv) * argv_len); + if (NULL == argv_new) { + perror ("realloc"); + free_n_strings (argv, argv_len-1); + free (tok); + exit (1); + } + argv = argv_new; + + argv[argv_len-1] = tok; + } } - argv[i] = NULL; + + /* NULL terminate the argument list */ + argv_len++; + char **argv_new = realloc (argv, sizeof (*argv) * argv_len); + if (NULL == argv_new) { + perror ("realloc"); + free_n_strings (argv, argv_len-1); + exit (1); + } + argv = argv_new; + + argv[argv_len-1] = NULL; return argv; } diff --git a/guestfish.pod b/guestfish.pod index d24c162..affb83b 100644 --- a/guestfish.pod +++ b/guestfish.pod @@ -250,9 +250,13 @@ quotes. For example: rm '/"' A few commands require a list of strings to be passed. For these, use -a space-separated list, enclosed in quotes. For example: +a whitespace-separated list, enclosed in quotes. Strings containing whitespace +to be passed through must be enclosed in single quotes. A literal single quote +must be escaped with a backslash. vgcreate VG "/dev/sda1 /dev/sdb1" + command "/bin/echo 'foo bar'" + command "/bin/echo \'foo\'" =head1 WILDCARDS AND GLOBBING diff --git a/regressions/Makefile.am b/regressions/Makefile.am index 3279f95..9112b94 100644 --- a/regressions/Makefile.am +++ b/regressions/Makefile.am @@ -32,7 +32,8 @@ TESTS = \ test-qemudie-synch.sh \ test-read_file.sh \ test-remote.sh \ - test-reopen.sh + test-reopen.sh \ + test-stringlist.sh SKIPPED_TESTS = \ test-bootbootboot.sh diff --git a/regressions/test-stringlist.sh b/regressions/test-stringlist.sh new file mode 100755 index 0000000..0b0c476 --- /dev/null +++ b/regressions/test-stringlist.sh @@ -0,0 +1,60 @@ +#!/bin/sh - +# libguestfs +# Copyright (C) 2009 Red Hat Inc. +# +# 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., 675 Mass Ave, Cambridge, MA 02139, USA. + +# Test remote control of guestfish. + +set -e + +rm -f test.img + +eval `../fish/guestfish --listen` + +error=0 + +function check_echo { + test=$1 + expected=$2 + + local echo + + echo=$(../fish/guestfish --remote echo_daemon "$test") + if [ "$echo" != "$expected" ]; then + echo "Expected \"$expected\", got \"$echo\"" + error=1 + fi +} + +../fish/guestfish --remote alloc test.img 10M +../fish/guestfish --remote run + +check_echo "' '" " " +check_echo "\'" "'" +check_echo "'\''" "'" +check_echo "'\' '" "' " +check_echo "'\'foo\''" "'foo'" +check_echo "foo' 'bar" "foo bar" +check_echo "foo' 'bar" "foo bar" +check_echo "'foo' 'bar'" "foo bar" +check_echo "'foo' " "foo" +check_echo " 'foo'" "foo" + +../fish/guestfish --remote exit + +rm -f test.img + +exit $error diff --git a/src/generator.ml b/src/generator.ml index 71aeeed..fa08688 100755 --- a/src/generator.ml +++ b/src/generator.ml @@ -6362,7 +6362,8 @@ and generate_fish_cmds () = pr " %s = strcmp (argv[%d], \"-\") != 0 ? argv[%d] : \"/dev/stdout\";\n" name i i | StringList name | DeviceList name -> - pr " %s = parse_string_list (argv[%d]);\n" name i + pr " %s = parse_string_list (argv[%d]);\n" name i; + pr " if (%s == NULL) return -1;\n" name; | Bool name -> pr " %s = is_true (argv[%d]) ? 1 : 0;\n" name i | Int name -> -- 1.8.3.1