BASH PATCH REPORT ================= Bash-Release: 3.1 Patch-ID: bash31-010 Bug-Reported-by: vw@vonwolff.de Bug-Reference-ID: <20060123135234.1AC2F1D596@wst07.vonwolff.de> Bug-Reference-URL: http://lists.gnu.org/archive/html/bug-bash/2006-01/msg00090.html Bug-Description: There is a difference in behavior between bash-3.0 and bash-3.1 involving parsing of single- and double-quoted strings occurring in old-style command substitution. The difference has to do with how backslashes are processed. This patch restores a measure of backwards compatibility while the question of POSIX conformance and ultimately correct behavior is discussed. THIS IS AN UPDATED PATCH. USE THIS COMMAND TO REVERSE THE EFFECTS OF THE ORIGINAL PATCH. THE CURRENT DIRECTORY MUST BE THE BASH-3.1 SOURCE DIRECTORY. patch -p0 -R < bash31-010.orig Then apply this patch as usual. Patch: *** bash-3.1/parse.y Fri Nov 11 23:14:18 2005 --- bash-3.1/parse.y Thu Feb 23 08:21:12 2006 *************** *** 2716,2721 **** --- 2723,2729 ---- #define P_ALLOWESC 0x02 #define P_DQUOTE 0x04 #define P_COMMAND 0x08 /* parsing a command, so look for comments */ + #define P_BACKQUOTE 0x10 /* parsing a backquoted command substitution */ static char matched_pair_error; static char * *************** *** 2725,2736 **** int *lenp, flags; { int count, ch, was_dollar, in_comment, check_comment; ! int pass_next_character, nestlen, ttranslen, start_lineno; char *ret, *nestret, *ttrans; int retind, retsize, rflags; count = 1; ! pass_next_character = was_dollar = in_comment = 0; check_comment = (flags & P_COMMAND) && qc != '\'' && qc != '"' && (flags & P_DQUOTE) == 0; /* RFLAGS is the set of flags we want to pass to recursive calls. */ --- 2733,2744 ---- int *lenp, flags; { int count, ch, was_dollar, in_comment, check_comment; ! int pass_next_character, backq_backslash, nestlen, ttranslen, start_lineno; char *ret, *nestret, *ttrans; int retind, retsize, rflags; count = 1; ! pass_next_character = backq_backslash = was_dollar = in_comment = 0; check_comment = (flags & P_COMMAND) && qc != '\'' && qc != '"' && (flags & P_DQUOTE) == 0; /* RFLAGS is the set of flags we want to pass to recursive calls. */ *************** *** 2742,2752 **** start_lineno = line_number; while (count) { ! #if 0 ! ch = shell_getc ((qc != '\'' || (flags & P_ALLOWESC)) && pass_next_character == 0); ! #else ! ch = shell_getc (qc != '\'' && pass_next_character == 0); ! #endif if (ch == EOF) { free (ret); --- 2750,2757 ---- start_lineno = line_number; while (count) { ! ch = shell_getc (qc != '\'' && pass_next_character == 0 && backq_backslash == 0); ! if (ch == EOF) { free (ret); *************** *** 2771,2779 **** continue; } /* Not exactly right yet */ ! else if (check_comment && in_comment == 0 && ch == '#' && (retind == 0 || ret[retind-1] == '\n' || whitespace (ret[retind -1]))) in_comment = 1; if (pass_next_character) /* last char was backslash */ { pass_next_character = 0; --- 2776,2791 ---- continue; } /* Not exactly right yet */ ! else if MBTEST(check_comment && in_comment == 0 && ch == '#' && (retind == 0 || ret[retind-1] == '\n' || whitespace (ret[retind - 1]))) in_comment = 1; + /* last char was backslash inside backquoted command substitution */ + if (backq_backslash) + { + backq_backslash = 0; + /* Placeholder for adding special characters */ + } + if (pass_next_character) /* last char was backslash */ { pass_next_character = 0; *************** *** 2814,2819 **** --- 2824,2831 ---- { if MBTEST((flags & P_ALLOWESC) && ch == '\\') pass_next_character++; + else if MBTEST((flags & P_BACKQUOTE) && ch == '\\') + backq_backslash++; continue; } *************** *** 2898,2904 **** } else if MBTEST(qc == '`' && (ch == '"' || ch == '\'') && in_comment == 0) { ! nestret = parse_matched_pair (0, ch, ch, &nestlen, rflags); goto add_nestret; } else if MBTEST(was_dollar && (ch == '(' || ch == '{' || ch == '[')) /* ) } ] */ --- 2910,2920 ---- } else if MBTEST(qc == '`' && (ch == '"' || ch == '\'') && in_comment == 0) { ! /* Add P_BACKQUOTE so backslash quotes the next character and ! shell_getc does the right thing with \. We do this for ! a measure of backwards compatibility -- it's not strictly the ! right POSIX thing. */ ! nestret = parse_matched_pair (0, ch, ch, &nestlen, rflags|P_BACKQUOTE); goto add_nestret; } else if MBTEST(was_dollar && (ch == '(' || ch == '{' || ch == '[')) /* ) } ] */ *** bash-3.1/patchlevel.h Wed Jul 20 13:58:20 2005 --- bash-3.1/patchlevel.h Wed Dec 7 13:48:42 2005 *************** *** 26,30 **** looks for to find the patch level (for the sccs version string). */ ! #define PATCHLEVEL 9 #endif /* _PATCHLEVEL_H_ */ --- 26,30 ---- looks for to find the patch level (for the sccs version string). */ ! #define PATCHLEVEL 10 #endif /* _PATCHLEVEL_H_ */