From: Richard W.M. Jones Date: Thu, 14 Jul 2011 17:17:39 +0000 (+0100) Subject: fish: Handle backslash escapes in guestfish double-quoted strings. X-Git-Tag: 1.11.18~13 X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=commitdiff_plain;h=617e7f6bafa7de2303c08e1715004aae3141c389 fish: Handle backslash escapes in guestfish double-quoted strings. --- diff --git a/fish/fish.c b/fish/fish.c index a57472f..4e45cea 100644 --- a/fish/fish.c +++ b/fish/fish.c @@ -61,6 +61,7 @@ static void shell_script (void); static void script (int prompt); static void cmdline (char *argv[], int optind, int argc); static struct parsed_command parse_command_line (char *buf, int *exit_on_error_rtn); +static int parse_quoted_string (char *p); static int execute_and_inline (const char *cmd, int exit_on_error); static void initialize_readline (void); static void cleanup_readline (void); @@ -758,9 +759,8 @@ parse_command_line (char *buf, int *exit_on_error_rtn) */ if (*p == '"') { p++; - len = strcspn (p, "\""); - if (p[len] == '\0') { - fprintf (stderr, _("%s: unterminated double quote\n"), program_name); + len = parse_quoted_string (p); + if (len == -1) { pcmd.status = -1; return pcmd; } @@ -771,7 +771,6 @@ parse_command_line (char *buf, int *exit_on_error_rtn) pcmd.status = -1; return pcmd; } - p[len] = '\0'; pend = p[len+1] ? &p[len+2] : &p[len+1]; } else if (*p == '\'') { p++; @@ -835,6 +834,87 @@ parse_command_line (char *buf, int *exit_on_error_rtn) return pcmd; } +static int +hexdigit (char d) +{ + switch (d) { + case '0'...'9': return d - '0'; + case 'a'...'f': return d - 'a' + 10; + case 'A'...'F': return d - 'A' + 10; + default: return -1; + } +} + +/* Parse double-quoted strings, replacing backslash escape sequences + * with the true character. Since the string is returned in place, + * the escapes must make the string shorter. + */ +static int +parse_quoted_string (char *p) +{ + char *start = p; + + for (; *p && *p != '"'; p++) { + if (*p == '\\') { + int m = 1, c; + + switch (p[1]) { + case '\\': break; + case 'a': *p = '\a'; break; + case 'b': *p = '\b'; break; + case 'f': *p = '\f'; break; + case 'n': *p = '\n'; break; + case 'r': *p = '\r'; break; + case 't': *p = '\t'; break; + case 'v': *p = '\v'; break; + case '"': *p = '"'; break; + case '\'': *p = '\''; break; + case '?': *p = '?'; break; + + case '0'...'7': /* octal escape - always 3 digits */ + m = 3; + if (p[2] >= '0' && p[2] <= '7' && + p[3] >= '0' && p[3] <= '7') { + c = (p[1] - '0') * 0100 + (p[2] - '0') * 010 + (p[3] - '0'); + if (c < 1 || c > 255) + goto error; + *p = c; + } + else + goto error; + break; + + case 'x': /* hex escape - always 2 digits */ + m = 3; + if (c_isxdigit (p[2]) && c_isxdigit (p[3])) { + c = hexdigit (p[2]) * 0x10 + hexdigit (p[3]); + if (c < 1 || c > 255) + goto error; + *p = c; + } + else + goto error; + break; + + default: + error: + fprintf (stderr, _("%s: invalid escape sequence in string (starting at offset %d)\n"), + program_name, (int) (p - start)); + return -1; + } + memmove (p+1, p+1+m, strlen (p+1+m) + 1); + } + } + + if (!*p) { + fprintf (stderr, _("%s: unterminated double quote\n"), program_name); + return -1; + } + + *p = '\0'; + return p - start; +} + /* Used to handle " + +Alert (bell) character. + +=item C<\b> + +Backspace character. + +=item C<\f> + +Form feed character. + +=item C<\n> + +Newline character. + +=item C<\r> + +Carriage return character. + +=item C<\t> + +Horizontal tab character. + +=item C<\v> + +Vertical tab character. + +=item C<\"> + +A literal double quote character. + +=item C<\ooo> + +A character with octal value I. There must be precisely 3 octal +digits (unlike C). + +=item C<\xhh> + +A character with hex value I. There must be precisely 2 hex +digits. + +In the current implementation C<\000> and C<\x00> cannot be used +in strings. + +=item C<\\> + +A literal backslash character. + +=back + =head1 OPTIONAL ARGUMENTS Some commands take optional arguments. These arguments appear in this diff --git a/regressions/Makefile.am b/regressions/Makefile.am index a612ee3..726fb76 100644 --- a/regressions/Makefile.am +++ b/regressions/Makefile.am @@ -42,6 +42,7 @@ TESTS = \ test-find0.sh \ test-guestfish-a.sh \ test-guestfish-d.sh \ + test-guestfish-escapes.sh \ test-guestfish-tilde.sh \ test-inspect-fstab.sh \ test-launch-race.pl \ diff --git a/regressions/test-guestfish-escapes.sh b/regressions/test-guestfish-escapes.sh new file mode 100755 index 0000000..6f4f434 --- /dev/null +++ b/regressions/test-guestfish-escapes.sh @@ -0,0 +1,78 @@ +#!/bin/bash - +# libguestfs +# Copyright (C) 2011 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 guestfish string escapes. + +set -e + +rm -f test.output test.error + +../fish/guestfish <<'EOF' 2>test.error | od > test.output +echo "" +echo " " +echo " " +echo "\n" +echo "\r" +echo "\n\n" +echo "\x01" +echo "\001" +echo "\100" + +# These are invalid: +-echo "\x00" +-echo "\000" +-echo "\x" +-echo "\x0" +-echo "\7" +-echo "\77" +-echo "\777" +-echo "\" +-echo "\\\" +-echo " +-echo """ +EOF + +if [ "$(cat test.error)" != "\ +guestfish: invalid escape sequence in string (starting at offset 0) +guestfish: invalid escape sequence in string (starting at offset 0) +guestfish: invalid escape sequence in string (starting at offset 0) +guestfish: invalid escape sequence in string (starting at offset 0) +guestfish: invalid escape sequence in string (starting at offset 0) +guestfish: invalid escape sequence in string (starting at offset 0) +guestfish: invalid escape sequence in string (starting at offset 0) +guestfish: unterminated double quote +guestfish: unterminated double quote +guestfish: unterminated double quote +guestfish: command arguments not separated by whitespace" ]; then + echo "unexpected stderr from guestfish:" + cat test.error + echo "[end of stderr]" + exit 1 +fi + +if [ "$(cat test.output)" != "\ +0000000 020012 020012 005040 005012 005015 005012 000412 000412 +0000020 040012 000012 +0000023" ]; then + echo "unexpected stdout from guestfish:" + cat test.output + echo "[end of stdout]" + exit 1 +fi + +rm -f test.output test.error